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How many schools Spring 2011 Issue 18 and teachers do you reach – worldwide? In this issue: Biomimetics: clingy as an octopus or slick as a lotus leaf?

Also:

News from the EIROs: Mars, snakes, robots and DNA

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About Science in School Science in School promotes inspiring science teaching by encouraging communication between Editorial teachers, scientists and everyone else involved in European science education. The journal addresses science teaching both across Europe and across disciplines: highlighting the best in teaching and cutting-edge research. It covers not only biology, physics and chemistry, but also earth sciences, engineering and medicine, Happy birthday, focusing on interdisciplinary work. The contents include teaching materials; cutting-edge science; interviews with young scientists and inspiring Science in School! teachers; reviews of books and other resources; and European events for teachers and schools. Science in School is published quarterly, both online his issue of Science in School is rather special: it’s now and in print. The website is freely available, with five years since Science in School was launched, in articles in many European languages. The English- T language print version is distributed March 2006. free of charge within Europe. During the past five years we have published 350 articles, on Contact us Dr Eleanor Hayes / Dr Marlene Rau topics ranging from particle physics and astronomy, via cli- Science in School mate change, earthquakes and spectrometry, to evolution, European Molecular Biology Laboratory biodiversity and diabetes. Many of those articles have been Meyerhofstrasse 1 69117 Heidelberg translated for publication on our website – producing a fur- Germany ther 788 articles in 28 European languages. [email protected] Likewise, our readership continues to grow and grow: about 15 000 copies of the Subscriptions Register online to: English-language print journal are distributed across 41 European countries, and · Receive an email alert when each issue is our website receives well over 30 000 visitors from across the world every month published – a figure that continues to rise. Science in School is read not only by teachers, · Request a free print subscription (within Europe) · Swap ideas with teachers and scientists in the but also by teacher trainers, scientists and many others who are interested in Science in School online forum science education. · Post comments on articles in Science in School. Submissions Perhaps you, as one of our readers, have wondered who is behind Science in We welcome articles submitted by scientists, teachers School? Who makes it possible for science educators across the world to share and others interested in European science education. inspiring teaching ideas or keep up-to-date with cutting-edge science – for free? See the author guidelines on our website. Referee panel First, there are the publishers of Science in School: the eight European inter-gov- Before publication, Science in School articles are ernmental research organisations that make up EIROforum (see page 2). The idea reviewed by European science teachers to check that for the journal was born of EIROforum’s commitment to supporting and improv- they are suitable for publication. If you would like to join our panel of referees, please read the guidelines ing science education in Europe, and EIROforum has funded the journal right on our website. from the beginning. From 2005 to 2008, there was also generous support from Book reviewers the European Commission. If you teach science in Europe and would like to review books or other resources for Science in Francesco Romanelli, current chairman of EIROforum, explains: “EIROforum School, please read the guidelines on our website. recognises the importance of science education, both to train the next generation Translators of scientists and to ensure a scientifically literate public. Teachers are a vital ele- We offer articles online in many European languages. If you would like to volunteer to translate articles into ment in this process, and we are proud and happy to support them with Science your own language, please read the guidelines for in School.” translators on our website. On a day-to-day level, the journal is run by a two-person editorial team. Before moving into publishing, both my colleague Dr Marlene Rau and I spent several Advertising in Science in School – new lower prices years in research: Marlene in developmental biology, and I in insect ecology. We Science in School is the only European journal aimed source, edit and sometimes write the articles; organise the copy-editing, layout, at secondary-school science teachers across Europe printing, distribution and translation; maintain the website; publicise the journal; and across the full spectrum of sciences. It is freely available online, and 15 000 full-colour printed sell advertisements and generally keep everything running. It’s a lot of work but copies are distributed each quarter. enormous fun. The readership of Science in School includes everyone involved in European science teaching, including: Of course, none of this would be possible without a great deal of voluntary help. · Secondary-school science teachers We currently have 76 referees – European science teachers who help us decide · Scientists which articles to publish and how they could be improved. More than 250 scien- · Primary-school teachers · Teacher trainers tists and teachers have volunteered to translate articles into languages from · Science communicators. Albanian and German to Portuguese and Ukrainian. And of course there are the Web advertisements authors, who share their teaching ideas and scientific knowledge with our readers. Reach over 30 000 science educators worldwide every month. We would like to extend our grateful thanks to these people and to everyone else · € 200-350 per week involved. We look forward to the next five years of Science in School! Print advertisements Reach over 15 000 readers per issue. · Full page: € 1495 Eleanor Hayes · Half page: € 999 Editor-in-Chief of Science in School · Quarter page: € 560 Back cover (full page): € 1995 [email protected] · Distribution www.scienceinschool.org Distribute flyers, DVDs or other materials to 3000 named subscribers or to all 15 000 print recipients. For more information, see www.scienceinschool.org/advertising or contact [email protected] sis_18_RZ_.qxq:Layout 1 15.03.2011 18:09 Uhr Seite 1

Contents

Editorial Welcome to the eighteenth issue of Science in School News from the EIROs 2 Mars, snakes, robots and DNA Events 6 Science on Stage: countdown to the international festival 10 Young scientists at the cutting edge: EIROforum prize winners 13 Young minds in science: the European Union Contest for Young Scientists 2010 17 Feature article 17 Battle of the birds: interview with Tim Birkhead Cutting-edge science 21 Moringa: the science behind the miracle tree 27 Uracil in DNA: error or signal? 32 A neural switch for fear Teaching activities 36 The resourceful physics teacher 40 Breeding dragons: investigating Mendelian inheritance 32 Science education projects 46 The heat is on: heating food and drinks with chemical energy 52 Biomimetics: clingy as an octopus or slick as a lotus leaf? Science topics 60 Single molecules under the microscope

Additional online material Teacher profile 40 Teacher solidarity: a UK-Rwandan physics project Scientist profile To sea with a blind scientist Reviews Bad Science Instructables website Relativity: A Very Short Introduction

Forthcoming events for schools: www.scienceinschool.org/events 52 See: www.scienceinschool.org/2010/issue18

At the end of each article in this issue, you may notice a square black and white pattern. With the aid of a smart phone, this QR code will lead you straight to the online version of the article. All you need to do is download a free QR code reader app (such as BeeTagg or i-Nigma) for your smart phone and scan the code with your phone’s camera. To find a suitable one for your phone, see: http://tinyurl.com/byk4wg Hint: the apps works better in good light conditions, and with a steady hand. You may also want to try holding your camera at different distances from the code. You can then use all the live links to the references and resources, download the PDF, send the article to your friends, leave comments, and much more. What do you think about this new fea- 60 ture? Does it work for you? Leave your feedback here: www.scienceinschool.org/QRfeedback Science in School Issue 18 : Spring 2011 1 sis_18_RZ_.qxq:Layout 1 15.03.2011 18:09 Uhr Seite 2

Mars, snakes robots and DNA

EIROforum, the publisher of Science in School, is a partnership of eight European inter-governmental scientific research organisations (EIROs). As regular readers of Science in School will know, the range of research done at these organisations varies widely – from molecular biology to astronomy, from fusion energy to space science. The equipment is also very disparate – including enormous particle accelerators; beams of neutrons or high-energy X-rays; large telescopes or the International Space Station. Whether individually or as part of EIROforum, the EIROs are also involved in many outreach and education activities – for school students, teachers or the general public. Science in School is one example of a joint EIROforum activity; this article details some of the other research and outreach activities of the EIROs.

Im a g For a list of EIROforum-related articles in Science in School, see: e c o www.scienceinschool.org/eiroforum u r t e s y

To learn more about EIROforum, o f

C see: www.eiroforum.org E R

CERN: young scientists in the making With help from CERN, some 700 Swiss primary-school children from the Geneva area will try out the scientific method for themselves this year. On 26 January 2011, 30 local primary-school teachers met at the site of the LHCb experiment for the launch of the ‘Dans la peau d’un chercheur’ (‘Be a scientist for a day’) project, a joint activity by CERN, PhysiScope (University of Geneva) and the local education authorities in Juliette Davenne (left) and Marie Bugnon the Pays de Gex and the Canton of Geneva. (centre) from CERN’s communication From February to June 2011, children aged 9-12 will carry out their own investigations group prepare the mystery boxes for to try to discover what is inside a mystery box, just like CERN scientists attempting to primary schools with Olivier Gaumer detect particles which cannot be seen with the naked eye. (right) of PhysiScope The pupils will begin by designing and carrying out experiments, after which they can compare their ideas and send questions to CERN scientists via the project website. In April and May, they even get to visit a CERN experiment or take part in a PhysiScope event – a Image courtesy of CERN chance to grill the physicists about their own experimental methods. Finally, the children will give a lecture of their own, just like real scientists do. For more information, visit the website (in French): www.cern.ch/danslapeaudunchercheur For more ideas for teaching about black boxes, see: www.scienceinschool.org/advent2010/day1 For a list of CERN-related articles in Science in School, see: www.scienceinschool.org/cern To learn more about CERN, see: www.cern.ch

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News from the EIROs

Science in School is published by EIROforum, a collaboration of research organisations. Eleanor Hayes, Editor-in-Chief of Science in School, reviews some of the latest news from the EIROforum members.

EMBL: the first annual schools lecture On 10 December 2010, Dr Jan Korbel addressed 150 school students and their teachers at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany. Several hundred

I m more watched live over the Internet from classrooms across

g e Europe. In the first in a series of annual EMBL Insight Lectures,

u Jan described the advances that have recently been made in

e s

y DNA sequencing technology and human genome analysis, and

o f

E the possible implications that these advances could have for dis-

F D

A ease research – particularly cancer research. Questions came

J E

T from both the lecture hall and classrooms via Skype. “As scientists we have an obligation to explain our research to the public, which Robotic arm inside obviously includes the young the JET fusion public who are still undecided reactor about their career path,” says Jan. Philipp Gebhardt, education officer at the European Learning Laboratory for the Life Sciences, EMBL’s education facility, which organised the lecture, EFDA-JET: fusion energy for schools points to the value of communicating science in such a way: Fusion holds many attractions for school students of all ages – “There is a great social aspect to this. Many people in different the concepts of atoms, the Sun and clean energy resonate just as countries can watch the same lecture at the same time and ask much with 5-year-olds as with pre-university students. Catering questions directly to the speaker. It makes it accessible to every- for this range has led the communications group at Culham, UK, one.” to develop different tools: on-site visits and off-site talks for the The lecture remains accessible, as it can be watched here: older children and school visits with the ‘Sun Dome’ – a sort of www.embl.org/ells/insightlectures mobile planetarium – to engage the younger children. For a list of EMBL-related articles in Science in School, see: Visits to EFDA-JET www.scienceinschool.org/embl are very popular. Some To learn more about EMBL, see: www.embl.org 1500 school students visited in 2010 and so many schools want to visit (and revisit) that bookings are now being made for 2012. Over the past 18 months, visiting school classes have had the additional excitement of getting a glimpse of the actual fusion reactor (JET), which is being refurbished. When it is operating, the reactor is of course sealed off for safety reasons. Even then, Image courtesy of EMBL Photolab however, visitors can see a full-scale model; this shows the interi- or of the reactor and the robotic arms that carry out most of the work inside (see image). Education manager Jo Silva is delighted that so many students

are learning about fusion: “It’s fantastic to see this enthusiasm

that hopefully will translate into a new generation of scientists a

and informed public.” o

To learn more about EFDA-JET, see: www.jet.efda.org o

For a list of Science in School articles related to EFDA-JET, see: é -

r r

www.scienceinschool.org/efdajet v

l r e a b n r d o K J a n

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ESA: walking on ‘Mars’ a

The first humans have landed u

on ‘Mars’! On 14 February 2011, y

Italian Diego Urbina, Russian E S

Alexandr Smoleevskiy and Chinese / L

Wang Yue took their first steps on the simulated Martian surface. ç

a d

The sandy 60 m2 terrain, designed to resemble the Gusev crater on a the Red Planet, is housed in the Institute of Biomedical Problems in Moscow, Russia, one storey above the cylindrical modules housing the crew. “Today, looking at this red landscape, I can feel how inspiring it An artist’s impression of the super-Earth exoplanet orbiting will be to [be] the first human to step foot on Mars,” said Diego at the star GJ 1214. The planet appears as a large crescent in the beginning of his three-hour ‘Mars-walk’ with Alexandr. the foreground with its red host star behind This was the highlight of the first full-duration simulated flight to Mars, the international Mars500 project with extensive participation by the European Space Agency (ESA). For more than eight ESO: first super-Earth atmosphere analysed months, Diego, Alexandr and Yue and three colleagues had been isolated on a virtual ‘flight to Mars’. Using the Very Large Telescope of the Once the mothership arrived in ‘orbit’ around Mars, Diego, European Southern Observatory (ESO), the Alexandr and Yue entered the lander on 8 February 2011 and atmosphere around a super-Earth exoplanet ‘landed’ on Mars four days later. After three Mars-walks, they has been analysed for the first time. The plan- returned to the mothership on 24 February, rejoining their col- et, which is known as GJ 1214b and has 6.5 leagues who had continued to orbit Mars. times the mass of Earth, was studied as it Finally, on 1 March 2011, the most difficult part of this psycho- passed in front of its parent star and some of logical study of long flights began: another eight months of monot- the starlight passed through the planet’s atmosphere. We now onous ‘interplanetary cruise’ to get back home. Except this time, know that the atmosphere is either mostly water in the form of the astronauts won’t be able to look forward to a trip to Mars. steam or dominated by thick clouds or hazes. To watch a video of the crew’s first Mars-walk, see: GJ 1214b lies about 40 light-years from Earth in the constella- www.esa.int/SPECIALS/Mars500/SEMRCFOT1KG_0.html tion of Ophiuchus (the Serpent Bearer), and its planetary nature For more information on the Mars500 project, including a down- was confirmed in 2009, also using ESO telescopes. Initial find- loadable information kit, text and video diaries by the crew, and ings suggested that it had an atmosphere, which has now been much more, see: www.esa.int/SPECIALS/Mars500 confirmed and studied in detail by an international team of The crew will even answer your personal questions by email (to astronomers, led by Jacob Bean (Harvard–Smithsonian Center for [email protected]). Keep them short and think carefully – Astrophysics). “This is the first super-Earth to have its atmosphere only the best questions will be relayed to them through ‘mission analysed. We’ve reached a real milestone on the road toward control’. characterising these worlds,” says Bean. To find out how scientists envisage that Mars could be made To learn more, see the press release (www.eso.org/public/news/ habitable for humans, see: eso1047/) and the research paper: Marinova M (2008) Life on Mars: terraforming the Red Planet. Bean JL (2010) A ground-based transmission spectrum of the Science in School 8: 21-24. super-Earth exoplanet GJ 1214b. Nature 468: 669–672. doi: www.scienceinschool.org/2008/issue8/terraforming 10.1038/nature09596 To learn more about the European Space Agency, see: www.esa.int Download the article free of charge on the Science in School For a list of all ESA-related articles published in Science in School, website (www.scienceinschool.org/2011/issue18/ see: www.scienceinschool.org/esa eiroforum#resources), or subscribe to Nature today: www.nature.com/subscribe. Diego Urbina and To find out more about the search for Earth-like exoplanets, see: Alexandr Smoleevskiy on Jørgensen UG (2006) Are there Earth-like planets around other stars? Science in School 2: 11-16. their simulated Marswalk www.scienceinschool.org/2006/issue2/exoplanet Fridlund M (2009) The CoRoT satellite: the search for Earth-like planets. Science in School 13: 15-18. Im a ge www.scienceinschool.org/2009/issue13/corot c o u r te and ESO exoplanet press kit: s y o www.eso.org/public/products/presskits/exoplanets f E S A For more information about ESO, see: www.eso.org / I P For a list of ESO-related articles in Science in School, see: M B www.scienceinschool.org/eso

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Im a g e c o u r t e

s y News from the EIROs

F E

European XFEL: L EIROforum’s new member A montage of the main European XFEL building with the underground In November experiment hall 2010, the seven original members of EIROforum were joined by a new, eighth member: the European X-ray Free-Electron Laser Facility (European XFEL), based in Hamburg, Germany. ILL: a silken surprise Like the other members of EIROforum, European XFEL is a European inter-governmental research organisation (EIRO), fund- For about five thousand years, silk has been a ed by member states. precious commodity, prized for its beauty, light- The facility will produce ultra-short X-ray flashes which will ness and strength. For three thousand years, the enable scientists to map the atomic details of viruses, decipher Chinese managed to keep a monopoly on the the molecular composition of cells, take three-dimensional lucrative silk trade by guarding the secret of images of the nano-world, film chemical reactions and study how to produce it. Finally, however, the secret processes such as those occurring deep inside planets. The got out: silk is produced by moth larvae, also known as silk- European XFEL is currently under construction, and the first X- worms. ray beams will be produced in 2014. Even today, silk continues to fascinate us. For example, how is As a member of EIROforum, European XFEL will contribute the silk fibre assembled from the protein precursors inside the not only to the funding, but also to the organisation and con- silkworm? A recent study at the Institut Laue-Langevin used neu- tents of Science in School. The editorial team are looking for- tron beams to reveal some unexpected properties of silk pro- ward to welcoming a new member to the editorial board and to teins. Usually, proteins are stable at a concentration of approxi- articles about the work of European XFEL. mately 1 mg / ml, and only start to aggregate at a concentration of about 5-10 mg / ml. The silk precursor proteins, however, To learn more about European XFEL, see: www.xfel.eu behave very differently. The concentration inside the silkworm can be up to 400 mg / ml and yet the proteins remain in solution. When the concentration drops, however, the proteins begin ESRF: shining light onto snake evolution to unfold and expand, eventually clumping together. Under lab conditions, the effect is rather like a neat ball of string unravel- If you ask someone to describe what ling into a tangled mess, but inside the silkworm, order reigns: characterises a snake, one of the answers is the insect controls the process, spinning the proteins into highly likely to be ‘no legs’. We know that this ordered silk filaments. These results are a big step towards under- wasn’t always the case – the ancestors of standing the amazing properties of silks and how to synthesise snakes probably looked similar to modern them and develop materials. lizards, but over time, they lost their legs. To learn more, see the press release on the ILL news website How did that happen? (www.ill.eu/nc/quick-links/news) or use the direct link: Scientists at the European Synchrotron Radiation Facility http://tinyurl.com/658slrp (ESRF) are helping to solve this puzzle using novel X-ray imag- See also the research paper: ing technology to investigate a fossilised snake, Eupodophis Greving I et al. (2010) Small angle neutron scattering of native descouensi, which lived 95 million years ago in Lebanon, and and reconstituted silk fibroin. Soft Matter 6: 4389-4395. doi: has two small limbs at its pelvis. The detailed 3D images 10.1039/C0SM00108B revealed that the internal architecture of these fossilised bones To find out about previous ILL research into spider silk, see: strongly resembles that of modern terrestrial lizard legs. Cicognani G, Capellas M (2007) Silken, stretchy and stronger Moreover, the results suggest that E. descouensi lost its legs not than steel! Science in School 4: 15-17. because they grew in a different pattern, but because they grew www.scienceinschool.org/2007/issue4/spidersilk more slowly, or for a shorter period of time, than those of their For a list of ILL-related articles in Science in lizard relatives. School, see: www.scienceinschool.org/ill To learn more, see the press release (www.esrf.eu/news/general/ To learn more about ILL, see: www.ill.eu Snake-with-leg) and the (freely available) research paper: Houssaye A et al. (2011) Three-dimensional pelvis and limb anatomy of the Cenomanian hind-limbed snake Eupodophis descouensi (Squamata, Ophidia) revealed by synchrotron-radia- A silkworm: larva of the domesticated Image courtesy of Chantal Argoud / ESRF Image courtesy of Chantal tion computed laminography. Journal of Vertebrate Paleontology 31(1): 2-7. doi: 10.1080/02724634.2011.539650 silkmoth To learn how to use For a list of ESRF-related articles in Science in School, see: this code, see page 1. www.scienceinschool.org/esrf ckphoto Image courtesy of arlindo71 / iSto To learn more about ESRF, see: www.esrf.eu

A detail of the Eupodophis descouensi fossil, with a finger pointing to the leg

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Science on Stage: countdown to the international festival Science on Stage brings together many of Europe’s most innovative and inspiring science teachers. Andrew Brown reviews some of the recent national activities.

cience on Stage offers a plat- old satellite dish and some alumini- also produces music? Jean-Michel form for European science um foil to make a steaming hot gour- Laclaverie and Elisabeth Martre’s stu- S teachers to share their teaching met meal. The foil was used to line dents studied the frequency of vibra- ideas, workshops and performances. the surface of the dish, creating a par- tions emitted by the Sun and used Via national events, teachers compete abolic reflector capable of concentrat- them to show how this ‘music’ com- for places at the Science on Stage ing the Sun’s energy. This solar cook- pares to that produced by more tradi- international teaching festival, which er proved sufficiently powerful to boil tional musical instruments. this year will be held in Copenhagen, water and even to make a delicious Denmark, on 16-19 Aprilw1. The 2011 chicken curry! Greece: Rainbows and Mars festival, with the motto of ‘Science Mathematics teacher Francis Loret On 15-16 October 2010, 3000 visitors teaching: winning hearts and minds’, challenged his 14-year-old students to – including 2000 students – flocked to will bring together 350 European sci- battle against him in the Internet’s the Hellenic Science on Stage eventw4 ence teachers. biggest virtual sailing race, the at the Laboratory Centre for Physical Vendée Globew3. Students were given Sciences of Aigaleo. There, teachers France: Solar-powered curry and expert training in the basic principles and students from across Greece pre- musical sunshine of sailing and in meteorology and the sented 110 high-school projects, The French organisers of Science on interpretation of weather maps. They including laboratory exhibits and two Stage, Science à l’Ecolew2, collaborated had to grapple with the unfamiliar student performances. with a national science contest for concepts of spherical geometry, which Physics teacher Elias Kalogirou middle- and high-school students underpin the calculations necessary to described how his students designed called CGenial. On 15 May 2010, 81 sail in the race. Of the 340 000 race experiments to explain the wonders projects were presented in Nantes and participants, Francis’s most accom- of the rainbow using their under- 12 teachers were selected to attend the plished student sailor finished in an standing of optics; why is a rainbow international Science on Stage festival impressive 216th place. coloured, why is it bow-shaped and this year. Mozart, Bach, Beethoven, how can we create one in the class- Guillaume Lebatard and Amandine Rachmaninoff… and the Sun? Who room? (Elias has also written an arti- Sultana described how their students, would have thought that in addition cle on microscale chemistry for Science aged 11-12, used little more than an to sustaining all life on Earth, the Sun in School: see Kalogirou, 2010.)

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Events

Creating the parabolic reflector Image courtesy of Guillaume Lebatard

Solar-powered cooking

Image courtesy of Guillaume Lebatard

Using everyday materials, Ioannis ume of a gas is reduced by a decrease such as: how does the solar wind Gatsios built 10 devices designed to in temperature. affect electronic equipment, and how teach his students about the behav- Theodoros Pierratos encouraged his can we produce the energy required iour of gases. One consisted of an students to think like astronauts. He to maintain a manned base on Mars? inflated balloon attached to a metal asked them to consider everything (Theodoros’s work has also been fea- bottle. When the bottle was plunged that is required to plan a trip to Mars tured in Science in School. See into liquid nitrogen at -190°C, the bal- and live on its surface. Classroom Patterson, 2009.) loon deflated, illustrating that the vol- experiments helped answer questions Image courtesy of Elias Kalogirou

Elias Kalogirou demonstrates why a rainbow is bow-shaped Image courtesy of Elias Kalogirou

www.scienceinschool.org Science in School Issue 18 : Spring 2011 7 , based at To learn how to use learn how To this code, see page 1. Science in School www.scienceinschool.org Investigating how solar wind solar how Investigating affects electronic equipment Science in School articles about Science on Stage, see: www.scienceinschool.org/sons graduated recently Brown Andrew Dimistra Milioni, president of the Milioni, president Dimistra education council of the municipality Aigaleo, learns about the ‘capaci- of tor in action’ project at the Science munici- The on Stage Greece event. Aigaleo is the main sponsor of paty of Science on Stage Greece Image courtesy of Theodoros Pierratos Theodoros of Image courtesy the European Molecular Biology the European Germany. Laboratory in Heidelberg, from the University of Bath, UK, with from in molecular and cellular a degree During his course, he took a biology. year out to work for the agrochemical he spe- company Syngenta where cialised in light and electron He now works as an microscopy. intern for festival. These books can be down- the Science from of charge loaded free website: on Stage Ireland www.scienceonstage.ie/resources.html all other view To Image courtesy ofTheodoros Pierratos

Image courtesy of Ioannis Gatsios on Stage Europe and to contact on Stage Europe see: your national organisers, www.science-on-stage.eu Stage France, see: www.sciencesalecole.org be found here: www.vendeeglobe.org/en see: Science on Stage Greece, www.physics.ntua.gr/ SOS-GREECE/contest.html and how to international festival apply to take part, see: http://science-on-stage.eu/?p=3 After each of the previous interna- After each of the previous Resources Web references Web about Science find out more w1 – To about Science on learn more w2 – To Globe can w3 – Details of the Vendée information about w4 – For more about the learn more w5 – To tional Science on Stage festivals (and the Physics on Stage festivals that pre- ceded them), the Irish delegates produced a book describing how to carry out their favourite experiments in the : 50-54. 12 Issue 18 : Spring 2011 : 27-32. 16 for details. Science in School w5 Science in School Science in School The balloon deflates when The it the metal bottle to which is immersed in is attached liquid nitrogen space. www.scienceinschool.org/2010/ issue16/microscale www.scienceinschool.org/2009/ issue12/spaceclassroom istry: experiments for schools. Science in School At each national Science on Stage For other science teachers who wish 8 Patterson L (2009) A classroom in classroom A (2009) Patterson L References chem- E (2010) Microscale Kalogirou Attending the international festival event, a fixed number of teachers their coun- selected to represent were try at the international Science on Stage festival in Copenhagen. For these teachers, participation will be free. to attend the international festival, a limited number of places are there fee will be for which a registration See the Science on Stage charged. website sis_18_RZ_.qxq:Layout 1 15.03.2011 18:09 Uhr Seite 8 Seite Uhr 18:09 15.03.2011 1 sis_18_RZ_.qxq:Layout sis_18_RZ_.qxq:Layout 1 15.03.2011 18:09 Uhr Seite 9 sis_18_RZ_.qxq:Layout 1 15.03.2011 18:10 Uhr Seite 10

Young scientists at the cutting edge: EIROforum prize winners

Courtney Williams, winner of the CERN prize at the European Union Contest for Young Scientists 2009, reports on her experiences and those of the other EIROforum prize winners.

n September 2009, in the Palais de prizes from the European Union, a Kristina Aare – studying bacteria la découverte in Paris, France, 132 number of special prizes are awarded in polluted water young scientists aged 14 to 21 each year, including one-week visits “My interest in science started in I w2 from Europe and beyond came to the EIROforum institutes – a secondary school, with a focus on together for the 21st European Union group of seven (now eight) research biology and chemistry, which led to Contest for Young Scientists organisations around Europe, incor- my successful participation in a num- (EUCYS)w1 (see Rau, 2009). As part of porating some of the world’s most ber of national competitions in my the contest, participants presented exciting science. One of the lucky home country of Estonia. My main original projects from all corners of winners in 2009, I will share with you passion is biochemistry, so I decided science and competed for prizes while my experiences and those of four to work on the project which was to sampling some of Paris’s world- other winners of the EIROforum win the European Molecular Biology famous culture and getting to know prizes that year. Laboratory [EMBL]w3 prize at each other. In addition to the main EUCYS.”

Kristina Aare, winner of the Jake Martin with his 2009 EMBL prize at EUCYS winner’s certificate

F R S 9 9 E 0 0 / 0 0 d -2 -2 u 5 5 o 9 9 g 9 9 r 1 1 A , , l s s ta ie ie n it it a n n h u u C m m f o m m y o o s C C e t r n n a a u e e o c p p o o e r r g u u a E E m I © ©

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Events

Image courtesy of techengine / iStockphoto

Kristina’s research was dedicated to of generating energy: it is the only blue glow of the reactor due to the the problem of environmental pollu- operational fusion experiment capable characteristic Cherenkov radiation tion with oil. She studied the soil bac- of actually producing fusion energy. was especially impressive. At the terium Pseudomonas putida, which has He received advice and information moment I am studying physics at an extremely high tolerance of phe- from scientists working there, and ETH Zürich, Switzerland, and thanks nol, toluene and other toxic organic learned more about how international to my visit to ESRF and ILL, I have a solvents found in oil. She is really co-operation plays a part in European better idea of which field I want to looking forward to her visit to EMBL science – a lot more so than in New work in afterwards.” in Heidelberg, Germany, and the Zealand. insights this will provide her with. Julian Petrasch – tracking Damian Steiger – building a asteroids from the computer Jake Martin – developing a new miniature particle accelerator In his winning project, ‘Sky way of creating fuel “My project was to design and Alignment Simulator (SAMS) – Jake travelled halfway around the build a small cyclotron, small enough improved determination of minor world to compete in EUCYS – from to fit on a desk. Therefore, I tried to planet positions’, Julian Petrasch from Auckland, New Zealand – and then apply as many new technologies as Germany developed software to again when he visited Culham, UK, possible to the design of the first measure the positions of asteroids for his visit to the European Fusion cyclotron, built in the 1930s. With my more precisely. The 17-year-old used Development Agreement - Joint project I showed a way of building the new software to pinpoint the posi- European Torus (EFDA-JET)w4. small cyclotrons with state-of-the-art tions of about 20 asteroids and two Jake, now 19, has been competing in technology and at low cost. In future space probes. He reports that some science fairs since he was 14. His some of the knowledge might be used publications on this topic from the EUCYS project consisted of a gasifier to build small and compact cyclotrons Berlin Observatory have already used he built, which turns wood into a fuel for medical applications or materials data processed with this new method. gas that can run a normal petrol research.” As the winner of the ESO prize, engine. Another output of his gasifier For his prize, Damian went to the Julian enjoyed the trip of a lifetime to is biochar, a type of charcoal you get European Synchrotron Radiation two of ESO’sw8 observatories in Chile from pyrolising biomass. The primary Facility (ESRF)w5 and the Institut Laue from 7 to 13 February 2010. “It was use of biochar is not as a fuel, howev- Langevin (ILL)w6 at their joint campus amazing to walk between these giant er, but to take carbon dioxide out of in Grenoble, France, where he visited telescopes and see how such large the atmosphere. For his prize Jake vis- all the different laboratories and con- machines can be controlled and ited the EFDA-JET facility, which trol rooms. “I enjoyed the visit to the moved so precisely just by one per- itself is looking at alternative methods reactor at ILL most,” he says. “The son,” he said after his visit to Paranal

Damian Steiger in front Julian Petrasch visiting the Courtney Williams pays a of ESRF Paranal Observatory in Chile visit to the CERN library

O ES f o sy e rt u o c e g N a R E Im C f o y s e t r u o c e g a

m I

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Image courtesy of techengine / iStockphoto

Observatory. Julian, who became an References Resources amateur astronomer when he was Rau M (2009) Discoveries in Paris: the To read Courtney’s full report on her only six years old, also feels deeply European Union Contest for Young stay at CERN and her experience as impressed by Chile, its nature, its Scientists. Science in School 13: 6-9. a EUCYS participant, see her blog: enormous distances and the astonish- www.scienceinschool.org/2009/ www.butrousfoundation.com/ ing silence of the desert. issue13/eucys09 ysjournal/?q=blog/70 Rau M (2011) Young minds in science: To learn more about the individual Courtney Williams – investigating the European Union Contest for EIROforum institutes, see: underwater neutrino detection Young Scientists 2010. Science in Unlike for many other contestants, EIROforum (2010) EIROforum: School 18: 13-16. EUCYS was my first international sci- introducing the publisher of Science www.scienceinschool.org/2011/ ence fair. My project, ‘Listening for in School. Science in School 15: 8-17. issue18/eucys2010 ghost particles: the acoustic cosmic www.scienceinschool.org/2010/ issue15/eiroforum ray neutrino experiment’, had two Web references aspects: analysing background noise Courtney describes how she came to from an underwater neutrino detec- w1 – Find out more about the be interested in physics in an article tor, and simulating the acoustic pulses European Union Contest for Young in Symmetry: that high-energy neutrinos should Scientists on their website: www.symmetrymagazine.org/ make when they enter water. http://ec.europa.eu/research/ cms/?pid=1000859 youngscientists EUCYS was a great experience and If you enjoyed reading this article, one of the best weeks I’ve ever had – For a preview of the 2011 contest to browse our collection of event quite apart from winning a prize. As be held in Helsinki, Finland, see: reports online: it happens, I was lucky enough to be http://eucys2011.tek.fi www.scienceinschool.org/events awarded the CERNw7 prize: when I w2 – To learn more about EIROforum visited the institute this summer, I and its research organisations, see: enjoyed learning about how all the www.eiroforum.org Courtney Williams is studying different detectors work, as well as w3 – The EMBL website can be found theoretical physics at Imperial College talking to people from different here: www.embl.org London, UK. Her main interests lie in departments, including the press neutrino physics and science commu- w4 – To find out more about office, the director general and the nication. She has worked at the EFDA-JET, see: www.jet.efda.org engineers. My trip has intensified my University of Sheffield and desire to work in neutrino astro- w5 – Visit the website of ESRF for Rutherford Appleton Laboratory, and physics and I’m really eager to go more information: www.esrf.eu written articles for publications back to CERN! w6 – To learn more about ILL, see: including IoP Interactions, E&T www.ill.eu Education and Symmetry. She is Further EIROforum winners w7 – For more information about involved in promoting physics to The other EIROforum winner at CERN, see: www.cern.ch young people as a British Science EUCYS 2009 was Ana Shvetsova from w8 – Learn more about ESO online: Association CREST Alumnus, Russia. Ana, who designed a vehicle www.eso.org Ignition Creative Spark and STEM to move on Venus, was awarded the ambassador. Her personal website can w9 w9 – Find more information on ESA European Space Agency prize. She be found at courtneywilliams.co.uk. explained her project in an online on their website: www.esa.int videow10. w10 – To watch Ana Shvetsova With the 22nd EUCYS event, which explain her project (in English with took place in 2010 Lisbon, Portugal French subtitles) see the To learn how to use (see Rau, 2011), the number of young www.universcience.tv website or this code, see page 1. scientists visiting the EIROforum use the direct link: organisations continues to grow. http://tinyurl.com/5vy9yub

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Events

Young minds in science: the European Union Contest for Young Scientists 2010

Marlene Rau reports on the 22nd European Union Contest for Young Scientists (EUCYS).

The Portuguese Monument to the sunny afternoon in Lisbon – The hall is abuzz with young con- Discoveries in Lisbon boatmen set sail from the testants (aged 14-21) who have trav- Ashores of the River Tejo, elled from across Europe and beyond. evoking thoughts of the many great We, the 18 members of the interna- explorers that have ventured forth tional jury, have a tough time choos- from here to discover uncharted terri- ing among these excellent projects: tories. It is a late September day in how can you compare the design of a 2010, and in the nearby Electricity flat-packed Christmas tree with Museum, 124 vibrant minds from 37 behavioural studies of birds; a collec- countries are presenting their own tion of Moroccan folk tales with a dig ventures into science. for dinosaur bones; face-recognition Image courtesy of Carlos Paes; image source: Wikimedia Commons © European Communities, 1995-2010

Lisbon’s Electricity Museum, host to the 2010 contest

www.scienceinschool.org Science in School Issue 18 : Spring 2011 13 sis_18_RZ_.qxq:Layout 1 15.03.2011 18:10 Uhr Seite 14 © European Communities, 1995-2010 quadrille with costumed guides in the Volha Shumskaya (aged 17) from baroque palace in Mafra; dine in the Belarus will travel to CERNw2, the adjoining monastery, served by sol- European Organization for Nuclear diers training for conflict zones; listen Research in Geneva, Switzerland, to talks on biodiversity and patenting; where enormous amounts of data are and satisfy their curiosity in the generated and processed every day. ‘Explore’ room at the Park of Nations This enthusiastic mathematician has Knowledge Pavilion: can you touch a studied the extrema of least common tornado? Are all shadows just black multiples and greatest common divi- and white? sors for sequences of numbers. Janis Francesco Romanelli, director general of And of course, there is much to Smits (aged 18) from Latvia is the EFDA-JET and chairman of EIROforum, explore inside the Electricity proud winner of a visit to the fusion presents the ILL prize to Radko Kotev. In w3 the background, CERN prize winner Museum, too: during the breaks, stu- reactor at EFDA-JET in Culham, UK. Volha Shumskaya (left) and ESA prize dents peruse the museum’s marvel- Like his host organisation, Janis is winner Vladimíra Bejdová (right) lous interactive exhibition. concerned with improving energy Finally, the 26 prizes are allocated. generation, and has developed a light algorithms with improved methods First-prize winners are Miroslav thin-layer lithium iron phosphate bat- for wastewater treatment; a gadget Rapcak and David Pegrimek from the tery to propel his bicycle. for identifying fraudulent drycleaners Czech Republic, who computer-pre- Vladimíra Bejdová (aged 19) from with a study on whether Internet dicted a complete phase diagram of the Slovak Republic will visit the w4 addiction causes brain lesions? CO2 nanoclusters; Márton Balassi and European Space Agency . The space The European Union suggests a Dávid Horváth from Hungary, who enthusiast has discovered and good recipe for creating a winning developed a computer simulation of analysed a new binary star in the project: “Choose a subject that inter- ecosystems for the classroom, which Andromeda constellation using a ests and inspires you (the idea must can also be used for risk assessment; small telescope. of course be an original one). Add a and Lukasz Sokolowski from Poland, The biologist among the little curiosity and know-how, a touch who studied the foraging strategy of EIROforum prize winners is Raghd of perseverance and obstinacy, some the ant Formica cinerea. Rostom (aged 19) from the UK. Her advice from specialists, a good pinch The ten main prizes sponsored by use of cells from embryonic chick of ingenuity, a large measure of a crit- the European Union are complement- bones as a model for osteogenic ver- ical mind, enthusiasm and an entered by a range of prestigious special sus chondrogenic differentiation in

© European Communities, 1995-2010 prising spirit and, above all, the best prizes, including those offered by stem cells won her a visit to the part of your imagination.” EIROforumw1: seven one-week stays at European Molecular Biology While the jury is locked in fierce one of its member organisations, each Laboratoryw5 in Heidelberg, Germany. discussions behind closed doors, the of which is awarded to a worthy par- Young astronomer Pavel Fadeev contestants explore Lisbon and its ticipant who would profit from a visit (aged 19) from Israel will travel to the surroundings: they dance the to that institute. European Southern Observatory’sw6 telescopes in Chile, where he can discuss his unique catalogue of 270 extragalactic star-forming regions with professional colleagues. Maths enthusiast Radko Kotev (aged 18) from Bulgaria was awarded a trip to the Institut Laue-Langevin (ILL)w7 for finding a new solution to the geometrical Apollonius problem –

The winners of the European Union prizes at EUCYS 2010

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Events

Sandro Young from Canada demonstrates his 3D user interface

And what is the contestants’ ver- dict? “I’m certain we will carry these memories with us for the rest of our lives: to meet other young scientists, to understand their projects and to share some ideas are our main goals during these days,” explains Guoda Radaviciute from Lithuania.

Image courtesy of the Portuguese Youth Foundation, Host Organiser of EUCYS 2010 EUCYS is a great experience for everyone involved – and we are already looking forward to EUCYS 2011 in Helsinki, Finlandw11. constructing a circle that is tangential the final ceremony, in 14 categories to three given circles. He will be such as ‘the funniest’, ‘the most Web references joined at the campus of ILL and the enthusiastic’ or ‘the most Portuguese’ w1 – For more information about European Synchroton Radiation project (which goes to the Brazilian EIROforum, see: w8 Facility (ESRF) in Grenoble, France, contestant). www.eiroforum.org by ESRF prize winner Sebastian The impact of EUCYS is something w2 – To learn more about CERN, see: Cincelli (aged 19) from Italy, a young Maximos Tsalas from EFDA-JET can

www.cern.ch Image courtesy of the Portuguese Youth Foundation, Host Organiser of EUCYS 2010 engineer who designed ‘social’ robots vouch for, too – together with Claus on wheels for exploring uncharted Habfast from ESRF, he offered an w3 – More information about areas. enjoyable evening of lectures on ener- EFDA-JET is available here: Read about these and all other gy to the students, demystifying the www.jet.efda.org award winners and their projects on concept of fusion energy, to coincide w4 – To learn more about the the EUCYS 2010 websitew9. with the theme of the Electricity European Space Agency, visit: Apart from explaining their projects Museumw10. “EIROforum has been a www.esa.int to the jury, the contestants also have part of this contest for many years, w5 – For more details about the the chance to present their work to the and last year’s winner is currently European Molecular Biology general public. Over 3000 students visiting EFDA-JET, working with us,” Laboratory, see: www.embl.org from schools across Portugal visit the says Maximos. “We are always look- w6 – More information about the EUCYS stands and marvel at their ing for bright minds, so we offer European Southern Observatory is peers’ ingenuous ideas. This may lay selected participants the opportunity available here: www.eso.org the foundation for the next generation to visit EIROforum organisations.” of EUCYS contestants. The event does have an impact, as João Amaral (aged 21) is well aware – one of the many Portuguese student helpers, he was himself a contestant in EUCYS 2007. These helpers not only solve any minor or major problems the contest- Contestants ants have, and guide them through exchanging their social programme, but this year ideas also give their own set of awards at

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Dancing the quadrille Dinner in the refectory of the Mafra monastery

w7 – For more information about the Resources Learn more about EIROforum and the research performed at its organisa- Institut Laue-Langevin, see: For more information on EUCYS, see tions here: www.ill.eu the European Commission website: w8 – To learn more about the http://ec.europa.eu/research/ EIROforum (2010) EIROforum: European Synchroton Radiation youngscientists introducing the publisher of Science in School. Science in School 15: 8-17. Facility, visit: www.esrf.eu To find out more about the national www.scienceinschool.org/2010/ w9 – The EUCYS 2010 website competitions and to contact your issue15/eiroforum includes information about all par- national organiser, see: ticipants, their projects and the con- http://ec.europa.eu/research/ If you enjoyed reading this article, take a look at the full collection of test, along with many pictures and youngscientists (under ‘who is event reports published in Science in videos: www.lisboa.eucys2010.eu involved?’) School. See: Read about how last year’s winners Further movies are available on the www.scienceinschool.org/ enjoyed their EIROforum visits: EUCYS YouTube channel. See: eventreports www.youtube.com/user/EUCYS2010 Williams C (2011) Young scientists at the cutting edge. Science in School w10 – The slides of Claus Habfast’s 18: 10-12. and Maximos Tsalas’s lectures can www.scienceinschool.org/2011/ Dr Marlene Rau was born in be downloaded from the Science in issue18/eucys2009 Germany and grew up in Spain. After School website: obtaining a PhD in developmental To learn more about energy, the topic www.scienceinschool.org/2011/ biology at the European Molecular of the EIROforum lectures at issue18/eucys2010#resources Biology Laboratory in Heidelberg, EUCYS, see the Science in School w11 – Learn more about the 2011 edi- Germany, she studied journalism and series of energy articles: Image courtesy of the Portuguese Youth Foundation, Host Organiser of EUCYS 2010 tion of EUCYS in Helsinki and enter went into science communication. www.scienceinschool.org/energy their slogan competition. See: Since 2008, she has been one of the http://eucys2011.tek.fi editors of Science in School.

Contestants from the Czech Republic analysed the habitat preferences of black (right) and common (left) redstarts. Unlike the males, females (middle) are very similar in both species

To learn how to use this code, see page 1.

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Feature article

Battle of the birds: Biology Evolution Animal Behaviour interview with Tim Ages 16+ If “nothing in biology makes sense except in the

Im a light of evolution” Birkhead g e c (Theodosius Dobzhanky, o

r t e 1900-1975) this article s

f will be appealing and

Tim Birkhead tells h

n enjoyable for all biology

i teachers. It focuses on t

Karin Ranero Celius about h Professor Tim Birkhead, promiscuous birds and his life and his research, Tim but also introduces anoth- teaching science students. Birkhead er interesting topic – animal promiscuity and sexual selection – which is

probably new for many Image courtesy of Julie Langford; image source: Wikimedia Commons e thou like the dunnock – the amous, however, the dunnocks – from readers and uncommon male and female impeccably a Victorian point of view – have “ in teaching evolution at faithful to each other,” said shockingly lax morals, with the B school. Reverend Frederick Morris in 1853. In female often mating with several an attempt to preach fidelity, he males. What would Reverend Morris The article is based on an encouraged his parishioners to have made of the scandalous truth? interview, so the style is pleasant and witty; more- behave like dunnocks (Prunella modu- Tim Birkhead, professor of behav- over some difficult points laris) – small, brown, rather plain- ioural ecology and the history of sci- (sperm competition and looking birds. Far from being monog- ence at Sheffield University, UK, has sperm choice) are explained in a clear and vivid way (for instance, in the synthesis of the battle Skomer Island’s most of sexes, as “maximum famous resident: fertilisation versus best the puffin fertilisation”). The story of Birkhead’s life and career is interesting and inspiring for young students attracted by the study of animal behaviour and evolution; his personal methodology in teaching the history of science will also provide science teachers with new and stimulating ideas. Finally, this article shows that the study of evolution is an ever charming and surprising adventure. Giulia Realdon, Italy REVIEW

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I m

a g e

c o u

r t e

s y

;

i m

a most species actively graduated from university in 1972. “I

o seek multiple partners just feel incredibly fortunate to have

r c

e to mate with, an evolu- been the right age, at the right place :

W i

k tionary strategy to get the and the right time,” he says. i

i very best sperm to fertilise Tim’s initial interest was in sea

The a

ever-faithful m their eggs. birds. In 1972, he started a project to

dunnock n s Indeed, rivalry between monitor guillemots on Skomer Island, males and discrimination by a nature reserve in Wales: he looked females extends beyond the sexu- at the adult and immature survival al act itself. Inside the female, the rates and the age of the first breeding sperm of different males fight for and reproductive success, as well as supremacy – this is sperm competi- assessing the effects of oil pollution devoted tion. At the same time, the female and climate change on the popula- nearly 40 years to the may be able to select the sperm that tion. Although the project continues study of promiscuity in birds. From are best for her – this is sperm choice. and he returns to Skomer Island regu- Darwin’s time up to the late 1960s it This is the true battle of the sexes. The larly, the focus of his research gradu- was thought that male animals com- males and females of each species are ally moved towards sex. In particular, peted for female partners, with the permanently locked in a struggle to post-copulatory sexual selection. strongest and most attractive males out-evolve each other, as their repro- Tim Birkhead’s research has helped impregnating the most females, and ductive anatomy and behaviour to re-shape our understanding of bird that females sought only the security change to achieve their conflicting mating systems. Why should a bird or of monogamy, copulating with multi- aims: maximum fertilisation versus an individual copulate with more ple partners only when forced. The best fertilisation. than one partner? What determines unladylike truth that gradually These radical ideas were just begin- which male fertilises the female’s eggs emerged, however, is that females of ning to emerge when Tim Birkhead when she has mated with several

Image courtesy of Francesca Birkhead

Tim Birkhead with a zebra finch, Taeniopygia guttata

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Feature article

Field courses and tutorials are Tim’s preferred teaching methods. “I think intellectual development hinges very strongly on personal exchange. Tutorials are important for students to hear us talking to them, and for them to answer so that we can help shape their arguments. In field courses, similarly. I love teaching field courses because you can see the kids grow in that week. I teach a field course that takes place in June. The first day is appalling, but by the end of the week they are fantastic. However, they have trouble retaining that knowledge and enthusiasm, so when they come back in September it’s as if nothing has happened. I feel we ought to be doing four or five field courses, and by the end of that time a lot of the information and enthusiasm and way of doing science would have stuck.” Doing science is important, but so is understanding science itself. “The history of science course that I teach is about doing science and what it The guillemot means to be a scientist. I try to teach it Image courtesy of davthy / iStockphoto in an unconventional way: I don’t let my students take notes because I want them to listen, to be inspired by partners? And how are sexual con- lots of wonderful birds. As we walked what I tell them and then go off and flicts resolved? His research involves back at the end of the day, a young do the necessary reading. For one of finding out what happens to the man sat looking through a telescope the major assessments, I take them to sperm of the male inside the female’s with a notebook and my dad just a place where, based on their reading reproductive tract and investigating looked at me and said: ‘You could do and a quote I give them, they have to the importance of sperm competition something like that when you get old- organise a conference for the day. It’s and sperm choice in determining er’.” And he did. which male fertilises the eggs. But Tim is not always the observer; In his ongoing quest to explore the often, he is the one in the spotlight. A nature of sexuality, Tim Birkhead good scientist must be able to com- Artist’s could be considered a paparazzo of municate his research and engage impression of the moment of fertilisa- nature – travelling to remote islands audiences by making it relevant tion: a sperm gains and bearing extreme discomfort in the and Tim does just that: he illus- entry to an hope of catching birds mating, and trates science with many sto- ovum

when they do, splashing their most ries, and he’s clever, funny, per- a

intimate details and pictures over the suasive and very clear. In fact, c

r t

pages of science journals. he is one of those teachers e

Tim’s passion for birds goes way whose lectures should be sched- f

back – to when he was 11. “On one uled early in the morning to c

memorable holiday in Wales, my make it worth the students’ while S

father took me to a little island called to get out of bed. What makes his p

o t

Bardsey Island – one of the most lessons so special? His enthusiasm is o beautiful places in the world, with surely part of the answer.

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rd up to them entirely how they inter- Resources Dawkins R (2006) The Selfish Gene, 3 edition. Oxford, UK: Oxford pret it, and how they give the presen- To learn more about Tim Birkhead, University Press. ISBN: tation, and everybody does it very see: 9780199291151 differently. They learn about the histo- www.sheffield.ac.uk/aps/staff/ ry of science by listening to their acadstaff/birkhead.html To see all previously published fea- peers.” ture articles in Science in School, see: To see one of Tim Birkhead’s talks, Tim also enjoys sharing his enthusi- www.scienceinschool.org/features see: asm for science with school students. www.thedolectures.co.uk/speakers “Two or three weeks ago I gave a talk /speakers-2009/tim-birkhead at a school where the students were Karin Ranero Celius obtained a incredibly mature. As I said, most of Another talk by Tim Birkhead (‘The bachelor’s degree in physics and psy- my research is on sexual selection and early birdwatchers’) can be watched chology, and then an MSc in museum reproduction, and I was a bit appre- on TED, an online collection of studies. Her passion for educating hensive about telling 16- and 17-year- lectures: others about the wonders of science olds about reproduction, but they www.ted.com/talks/tim_birkhead_ led her to become a science communi- were fantastic. They asked really the_wisdom_of_birds.html cator, concentrating mainly on out- innovative questions, and there wasn’t To learn more about research into reach and education, first at the IAC any silly giggling. I think with a dunnock promiscuity, see: (Instituto de Astrofisica de Canarias) in group like that, you could really get Davies, NB (1983) Polyandry, the Canary Islands, Spain, and then at across what science is, although with cloaca-pecking and sperm competi- the European Southern Observatory other types of kids it might be a bit tion in dunnocks. Nature 302: 334- in Munich, Germany. While writing difficult.” 336. doi: 10.1038/302334a0 this article, she was based at the Image courtesy of AlasdairJames / iStockphoto What would Reverend Morris have Download the article free of charge European Molecular Biology made of that talk, I wonder? Perhaps from the Science in School website Laboratory in Heidelberg, Germany, he too would have concluded that he (www.scienceinschool.org/2011/ and she now works for EJR-Quartz in would have been better preaching to issue18/birkhead#resources), or Leiden, the Netherlands. the dunnock about the virtuous ways subscribe to Nature today: of the human. www.nature.com/subscribe This article is based on an interview Haubold B (2007) Review of The To learn how to use with Tim Birkhead, as well as his lecture this code, see page 1. Selfish Gene and Richard Dawkins: ‘Darwin and post-copulatory sexual How a Scientist Changed the Way We selection’ at the 11th EMBL / EMBO Think. Science in School 5: 84-85. Science and Society Conference: The www.scienceinschool.org/2007/ Difference between the Sexes – From issue5/selfish Biology to Behaviour, on 5-6 November 2010.

Bardsey Island, North Wales

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Cutting-edge-science

Moringa: the science behind the miracle tree

Moringas have long been known as miracle A moringa pod trees. Now scientists are investigating their properties in depth, as Sue Nelson and Marlene Rau report.

n the foothills of the Himalayas grow trees, five to ten metres tall, I with clusters of small oval leaves and delicately perfumed cream- coloured flowers. These are Moringa oleifera – the most widely cultivated of the 14 species of the genus Moringa, known as ‘miracle trees’. © WEDC, Loughborough University “It is called a miracle tree because every part of the tree has benefits,” says Balbir Mathur, president of Trees for Life Internationalw1, a US-based non-profit organisation that provides A flower from a moringa tree Moringa leaves developmental aid through planting fruit trees, moringas among them. “The roots, leaves, bark, parts of the one of the few trees that produce fruit fection, to kill those pathogens that fruits and seeds – everything. The list during a drought. still remain, using chlorine com- is endless.” It is yet another useful property of pounds, ozone, hydrogen or ultravio- Reports in the press about the Moringa oleifera, though, that is excit- let light. miraculous nature of the tree may be ing scientists: when crushed, moringa Moringa oleifera can help with the exaggerated, but it does have some seeds can help purify dirty water. first purification step – not only in the truly impressive properties. Native to This could save lives: the World developing world but also in the northern India but now found widely Health Organization estimates that developed world. In industrial water in Asia, Africa and Latin America, unsafe water, poor sanitation and treatment plants, the most prevalent moringas have been used in villages inadequate hygiene cause about 1.6 coagulating agents used today are in developing countries for hundreds million deaths a year globally. aluminium salts. Most particles that of years, their uses ranging from tra- Water purification is mainly a two- need to be removed from water are ditional medicine, food and cooking step process: initially, water is clari- charged, so coagulating agents are oil, to natural pesticide, domestic fied, removing particles such as min- usually ions; because the coagulating cleaning agent, and – the latest addi- erals, plant residues and bacteria. efficiency increases with the square of tion – biofuel. However, since not all particles readi- the coagulating agent’s ionic charge, Moringas are extremely hardy, ly sink to the bottom, coagulating polyvalent ions such as aluminium known in parts of Africa as nebedies, agents are added to help clump the are very efficient. However, there is meaning ‘never-die trees’, because particles together; these clumps can concern – albeit controversial – that they grow on marginal soils, regrow then be removed by filters or sedi- long-term exposure to aluminium after being chopped down, and are mentation. The second step is disin- may be associated with the develop-

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Biology Chemistry Biochemistry The M. oleifera tree Physics Personal, social and health education Ages 7-18

This is a thought-provoking article that uses theoreti- · In this article, a variety of uses are given for the cal science (binding abilities of ions, neutron reflec- moringa, including medicine, food, and cooking tion techniques) to explain a real-life situation (using oil. Suggest which parts of the tree might be used seeds to purify water). for which of the given uses in the article. Ideas from this article could be used with students of (Answers need not be correct, as students are not all ages to carry out some innovative practical work, expected to know, but they should be reasonable with appropriate risk assessments. M. oleifera seeds suggestions, e.g. oil from seeds; medicine from can be bought via the Internet, if you are not lucky any part; food from fruit; pesticide from leaves; enough to have them grow locally, and their effects cleaning agent from roots.) on clarifying water can be compared to those of other · Moringas ‘regrow after being chopped down’ and seeds. Are M. oleifera seeds really much better? are also described as being ‘one of the few trees Younger students could have a lot of fun grinding up that will produce fruit during a drought.’ Suggest different seeds and coming up with different ways of what adaptations these trees might possess in measuring how clear their dirty water becomes. order to do this. Older students could take this further and carry out (Answer: again, students would not be expected investigations linked to using different parts of the to know the answer, but could come up with pos- seeds and relating this to seed biochemistry, or com- sible ideas such as new trees growing from seeds pare seeds treated in different ways, e.g. dried versus that were dispersed before the tree was cut down, fresh. Researching the scientific basis of the seed- or the chopping down acting as a kind of coppic- driven clarification process would certainly be chal- ing, causing more branches to grow. Being able to lenging for the most able students. produce fruit during a drought could be due to an extensive root system (deep and / or wide, like The article fits well into a number of curricular top- those of cacti), to leaves that reduce the transpira- ics: biology of seeds / biochemistry of extracts; chem- tion rate, or to mechanisms for absorbing dew, istry of water purification / physical behaviour of the such as shallow roots.) salts; physics – perhaps something to do with investigating density of layers – and looking at alternative The article can also form the basis of discussion. methods. The idea could form the basis of a cross- Possible topics include: curricular project with social science lessons, · The evidence for / against aluminium being impli- because of the good links with sustainability and cated in neurodegenerative diseases renewable resources. · The more unusual uses of plants The article is suitable as a comprehension exercise · The role of the media in scaremongering the pub- for students aged 16 and older. Possible questions to lic on flimsy scientific basis (such as the drop in ask in a biology lesson include: sales of aluminium saucepans, after it was pro- · Moringa oleifera is just one of 14 species of the posed that they may be harmful) ‘miracle tree’. Which part of the scientific name · Citizenship topics and / or theme days based on gives the genus, and which the species? water availability around the world. (Answer: genus: Moringa; species: Moringa oleifera) Sue Howarth, UK REVIEW

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Cutting-edge-science

ment of neurodegenerative diseases. © WEDC, Loughborough University Although a successful pilot study Iron salts are an alternative, but they was performed at Thyolo water treat- are more difficult to use, as their solu- ment works in Malawi in 1989-1994 bility changes with pH. (see Folkard & Sutherland, 2002), Further kinds of coagulating agents developing future industrial treat- include synthetic polymers, but, as ment methods from M. oleifera relies with the other coagulants, the sludge on knowing exactly what processes formed in the clarification process take place during the purification. needs to be disposed of: so even Moringa seeds: whole (left) and Researchers already know that the though synthetic polymers solve the cut open (right) active ingredient in the seeds is pro- problem of the putative link to neu- tein, which accounts for 30-40% of the rodegenerative diseases, their lack of dered seeds in a small cloth bag with seeds’ weight. There are at least two biodegradability is an issue. a thread attached. This is then swirled proteins that may be active: they are Since M. oleifera is both non-toxic around in the bucket of turbid water, water-soluble and quite small, about and biodegradable, and reported until the fine particles and bacteria 6-16 kDa, so they can readily diffuse reductions in the cloudiness, clay and clump together with M. oleifera pow- out of the cloth bags. At higher con- bacterial content of water after the der, sinking and settling to the bot- centrations, they aggregate even in application of M. oleifera seeds rival tom. For drinking water though, the solution due to their substantial the efficiency of aluminium salts (see water needs to be purified further – hydrophobic regions. The protein Ghebremichael et al., 2005), it seems by boiling, filtering through sand or adsorbs on to contaminant particles, to be a viable alternative. placing it in direct sunlight in a clear which then clump together and can In certain rural areas of Sudan, bottle for a couple of hours (solaris- be separated and extracted. women already use M. oleifera to puri- ing; see Folkard et al., 1999). You can But how exactly does this clumping fy water: when collecting water from try a similar technique yourself in work? Scientists from the University the River Nile, they place the pow- class (see box on page 24). of Uppsala, Sweden, and the

Image courtesy of Dr Majority Kwaambwa, University of Botswana

Moringa oleifera

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Science inSchool CLASSROOM ACTIVITY .Addthepowder (approximately2g)toonecupof 3. Crushtheseedkernelstoafinepowder andsieve 2. Remove theseedsfromdriedpods,ifstillpres- 1. cation. petition forthemostefficientmethodofwater purifi- a differentwater purificationmethod),andrunacom- methods (seeMitchell etal.,2008,foranexampleof with You may want tocomparethewater qualityachieved amount ofpowder andtheoptimalstirringtimes. of water inajarwillhelpyou work outthecorrect slightly turbidwater. Experimentingwithsmallamounts sufficient foronelitreofvery turbidortwo litresof water: asaruleofthumb,powder fromoneseedwillbe Around 50-150mgofgroundseedstreatonelitre der topurifyit,dependingontheimpuritiespresent. Seeds ofthe Cleaning water seeds withmoringa Water willrequiredifferentamountsof online, asthetreeisgrown fordecorative purposes. utes. clean water, pourintoabottle andshakefor5min- them (0.8mmmeshorsimilar). of damage. Discard any kernelswithdarkspotsorothersigns ent, andshellthem,leaving awhitish kernel. M. oleifera Issue 18:Spring2011 Moringa oleifera seeds tothatachieved withother tree arecheaply available water andsilica(silicondioxide,SiO adsorbs ontoaninterfacebetween seeds tostudyhowtheprotein all thewater-soluble protein from the They produced apurifiedextractof further (seeKwaambwaetal.,2010). Botswana, setouttoinvestigate University ofBotswanainGaborone, to apowder beforeuse M. oleifera ure thethickness, densityandcoarse- called neutron reflectometry, tomeas- Grenoble, France, inatechnique the InstitutLaueLangevin water andmineralparticles. as amodelfortheinterfacebetween The teamusedaneutron beamat M. oleifera seeds areground pow- .Stirthewater quickly for2minutesandslowly for 5. Filter themixturethrough acleanclothinto 4. used asdrinkingwater. For safetyreasons,water purifiedinclassmustnotbe every timewater istobepurified. the paste(madeinstep4)shouldbefreshlymade Both theseedsandseedpowder canbestored,but Notes: The cleanwater may besiphonedorpouredoffthe 7. Cover thebucket andleave itundisturbeduntil the 6. w2 removed by this may re-introduceunwanted metalions 10-15 minutes(donotusemetalimplements,since bucket ofdirtywater thatistobetreated. and otherimpuritiesthatcauseturbidity. The processremoves atleast90%ofthebacteria top ofthebucket orfilteredthroughacleancloth. to thebottom. This may takeuptoanhour. water becomesclearandtheimpuritieshave sunk bucket. together andsinksettletothebottomof the fineparticlesandbacteriawillbegintoclump in 2 ) M. oleifera colours. Manymore materialsare each otherout,resulting indifferent layer, willeitheradduporcancel ing onthethicknessofpetrol be slightlyoutofphase,anddepend- layer. Thereflected lightwaveswill both thetopandbottomofpetrol descent colours:lightbouncesoff puddle, youcanseeavarietyofiri- When youseealayerofpetrol ona ness oftheformingprotein layer. Image courtesyofDrMajorityKwaambwa How doesthistechniquework? ). Duringtheslow mixing, www.scienceinschool.org seeds oleifera Moringa Dried sis_18_RZ_.qxq:Layout 1 15.03.2011 18:11 Uhr Seite 25

Cutting-edge-science

Images courtesy of Dr Majority Kwaambwa, University of Botswana

The mother of moringa researcher Dr Kwaambwa demonstrates how the seeds are treated for water purification

transparent to neutrons than to light, measured as a function of neutron who can do further research,” he says. and neutron wavelengths are also ‘colour’ (i.e. wavelength), telling sci- “It is not widely known in the about one thousand times shorter entists how many molecules thick the Western world yet because it doesn’t (0.2-2 nm) than those of light (about layer is, how densely packed the mol- grow there.” In the future, the miracle 0.5 μm), which is why a neutron beam ecules are, and how rough the surface tree could live up to its name. “The can be used to measure layers of proof the layer is. moringa could save millions of lives tein a single molecule thick. In the M. oleifera experiment, the around the world for years to come,” The ‘white’ neutron beam is shone scientists found that the seed protein states Mathur. “I cannot emphasise onto the sample, and reflectivity is forms dense layers thicker than a sin- enough how important it is.” gle molecule even at concentrations as Moringa protein in the adsorbed layer [%] low as 0.025 wt% – so the binding is References 50 very efficient. The surface of the lay- Folkard G, Sutherland J (2002) ers is remarkably smooth, but the Development of a naturally derived array of M. oleifera protein is not uni- coagulant for water and wastewater 40 form: further away from the silica treatment. Water Science and surface, the number of water mole- Technology: Water Supply 2(5-6): 30 cules among the protein increases, 89-94 which can be seen as a change in den- Folkard G, Sutherland J, Shaw R sity, as measured by neutron reflec- (1999) Water clarification using 20 tion (see diagram, left). Moringa oleifera seed coagulant. In This suggests that the clumping is Shaw, RJ (ed) Running Water: More so efficient because M. oleifera protein 10 Technical Briefs on Health, Water and has a strong tendency to bind both to Sanitation pp 109-112. Rugby, UK: IT mineral surfaces and to other M.

Publications. ISBN: 9781853394508 © WEDC, Loughborough University 0 oleifera protein molecules, even at -50 0 50 100 150 200 very low protein concentrations, due Ghebremichael KA et al. (2005) A sim- Distance from silica surface [Å] to hydrophobic regions and to the fact ple purification and activity assay -50 0 50 100 150 200 that, even when the overall protein is of the coagulant protein from

Image courtesy of Maja Hellsing electrically neutral, different sub- Moringa oleifera seed. Water Research groups of opposite charge will be 39: 2338-2344. doi: ionised. 10.1016/j.watres.2005.04.012 Work on M. oleifera proteins Kwaambwa HM, Hellsing M, Rennie continues to develop a non-toxic, AR (2010) Adsorption of a water biodegradable water purification treatment protein from Moringa treatment for which materials are oleifera seeds to a silicon oxide available locally and at a much lower surface studied by neutron reflec- cost than aluminium salts. Questions tion. Langmuir 26(6): being addressed include how much 3902-3910. doi: 10.1021/la9031046 seed protein is needed, whether other Mitchell WA et al. (2008) Science for proteins or biopolymers are suitable, the Next Generation: activities for and if other impurities in water, such primary school. Science in School 10: as natural detergents, affect the action Closest to the silica surface, M. oleifera 64-69. protein is packed very densely, in a layer of the process. www.scienceinschool.org/2008/ about two molecules thick (50 Å). Then, Mathur welcomes the scientific issue10/nextgeneration with increasing distance from the silica scrutiny. “We feel that the moringa surface, the concentration of adsorbed tree is very important and needs to be protein decreases rapidly brought to the attention of scientists The M. oleifera tree

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© WEDC, Loughborough University w2 – To learn more about the Institut How to Clone the Perfect Blonde, Sue Laue-Langevin, see: www.ill.eu Section of a has written for The Sunday Times, The moringa pod Observer, The Guardian and The Resources Independent and has contributed opin- If you enjoyed reading this article, ion columns on science for The Times. take a look at other Science in School Dr Marlene Rau was born in articles about research done at ILL. Germany and grew up in Spain. After See: www.scienceinschool.org/ill obtaining a PhD in developmental biology at the European Molecular Biology Laboratory in Heidelberg, Germany, she studied journalism and Sue Nelson is an award-winning went into science communication.

Web references UK science broadcaster and writer. A Since 2008, she has been one of the © WEDC, Loughborough University w1 – Trees for Life International pro- physics graduate, Sue also studied editors of Science in School. vides an international forum on space science and astronomy at the beneficial trees and plants, and has University of Michigan as a Knight been promoting the moringa tree Wallace journalism fellow in 2002 and for many years, sending literature recently completed a one-year Nesta Dream Time fellowship writing To learn how to use and information to universities, this code, see page 1. embassies and heads of state, as science-based dramas. Her reports well as producing educational have appeared on all the BBC’s material for schools. See: national TV and radio news bulletins. www.treesforlife.org Co-author of the popular science book sis_18_RZ_.qxq:Layout 1 15.03.2011 18:11 Uhr Seite 27

Cutting-edge-science

Biology Uracil in DNA: Genetics Immune system Insect development error or signal? Cell proliferation General cytology Enzyme pathways Uracil is well known as one of the bases Cancer research used in RNA, but why is it not used in Ages 16+ DNA – or is it? Angéla Békési and Beáta This article demonstrates that science never sleeps, G Vértessy investigate. shaking up the dogma that uracil only exists in RNA. As the article explains, this is not always the case. And even when it is, why should that be?

Image courtesy of spxChrome / iStockphoto and Nicola Graf To help the students understand the article, guiding questions could be: 1. Describe the bonding structures between Endopterygotes such as the two complemen- ants lack the enzyme tary base pairs in capable of removing DNA. uracil from their DNA 2. Which of the bases is replaced in RNA? 3. Describe and draw a graph of the repair enzyme pathway triggered when uracil is found in DNA. 4. The ratio of which molecules could be adjusted to stop can- cerous cells from Thymine versus uracil discovered, DNA forms a double growing and dividing? Our genetic information is stored in helix in which the four bases always 5. Why is uracil ‘tolerat- the form of DNA, using a four-letter pair up the same way, through specif- ed’ in RNA? alphabet. The four ‘letters’ correspond ic hydrogen bonds: adenine binds to to the four chemical bases that each thymine, and guanine to cytosine (see 6. Which living organ- building block of DNA – called a Figures 2 and 3). isms use uracil DNA nucleotide – can have: adenine (A), There is an alternative fifth letter, and how? thymine (T), cytosine (C) and guanine though: uracil (U), which forms the Friedlinde Krotscheck, (G; see Figure 1 on page 28). As James same pattern of hydrogen bonds with

REVIEW Austria Watson and Francis Crick famously adenine (see Figure 4). But although

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Figure 1 Figure 2 Figure 3

The key components of a nucleo- The chemical structure of DNA, The double helix structure of DNA tide, the basic building block of showing the base-pairings A-T DNA. The sugar deoxyribose and the and G-C. The hydrogen-bonded phosphate group are invariant, bases link together the two

whereas the organic base can be of Image courtesy of Madeleine Price Ball; image source: Wikimedia Commons sugar-phosphate backbones one of four types: A, T, G and C

Thymine Image courtesy of Forluvoft; image source: Wikimedia Commons Adenine Phosphate group Adenine P Organic base Thymine A,T,G or C Cytosine O Guanine

Image courtesy of Nicola Graf Phosphate- Sugar-phosphate desoxyribose backbone backbone

OH Deoxyribose

Cytosine Guanine

uracil is commonly used in RNA, this hydrolytic deamination (see Figure 4). one of the most common types of is not the case in DNA, where When this happens, the guanine that DNA damage, but is normally cor- thymine is used instead. Why might was initially bound to that cytosine rected effectively. How does the cell this be? molecule is left opposite uracil do this? Chemically, thymine is a uracil mol- instead (remember that uracil normal- Cells have a repair system that can ecule with an extra methyl group ly binds to adenine). When the cell detect when a uracil is sitting where a attached. What would be the advan- next replicates its DNA, the position cytosine should be, and correct the tage, in evolutionary terms, of using opposite this uracil molecule would mistake before it is replicated and this more complex building block in be taken up by an adenine instead of passed on. The complex machinery to DNA? The answer may lie in how the guanine that should be there, do that consists of several enzymes: cells correct damage to DNA. altering the message that this section first uracil-DNA glycosylases recog- Cytosine can spontaneously turn of DNA encodes (see Figure 5). This nise the uracil, and cut it out of the into uracil, through a process called process of cytosine deamination is DNA. Then several enzymes contribute to the elimination and re- Figure 4

Image courtesy of Angéla Békési synthesis of the damaged part of DNA, during which the abasic (‘emp- Guanine and cytosine form ty’) site in the DNA is replaced with a a base pair stabilised by three hydrogen bonds, cytosine (see Figure 6). Hydrolytic whereas adenine and However, the most common form of deamination thymine bind to each other uracil-DNA glycosylase cannot tell Uracil (U) through two hydrogen which base the uracil is paired with, Cytosine (C) bonds. The red frames high- i.e. whether the uracil was intended light the functional groups of to be there (if bound with adenine) or Guanine (G) cytosine and thymine that if it is a mutated cytosine (and is

are responsible for forming Image courtesy of taramol / iStockphoto the hydrogen bonds. opposite guanine); instead, it would Cytosine can spontaneously recognise and cut out both types of undergo hydrolytic deamina- uracil. Clearly, this would cause prob- tion, resulting in a uracil Thymine base with the same capabili- Adenine (A) (5-methyl uracil; T) ty for hydrogen bond forma- tion as thymine

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Cutting-edge-science

Figure 5 Figure 6 Thymine-less cell death Image courtesy of Nicola Graf Hydrolytic deamination of cytosine can Repair of hydrolytic When DNA is synthesised, the change the amino acids encoded by the deamination sequence DNA polymerase enzymes (which catalyse the synthesis) cannot dis- criminate between thymine and uracil. They only check whether the hydrogen bonds form correctly, i.e. 5’ ATC – C GT – TTG 3’ whether the base pairs are matched properly. To these enzymes, it does 5’ ATC – CGT – T TG 3’ transcription 3’ TAG – GUA – AAC 5’ I-R-L Uracil is replaced with cytosine 3’ TAG – GCA – AAC 5’ + translation not matter whether thymine or uracil Uracil-DNA Hydrolytic deamination glycosylases binds to adenine. Normally, the remove U amounts of deoxyuridine triphos- 5’ ATC – C GT – TTG 3’ phate (dUTP, a source of uracil) in the Arginine is replaced 5’ ATC – C GT – T TG 3’ 3’ TAG – GUA – AAC 5’ cell are kept very low compared to x by histidine 3’ TAG – GUA – AAC 5’ Resynthesis and levels of deoxythymidine triphos- Next replication reinsertion of phate (dTTP, a thymine source), pre- abasic site cytosine 5’ ATC – C A T – T TG 3’ transcription venting uracil incorporation during I-H-L 3’ TAG – GUA – AAC 5’ + translation DNA synthesis. x 5’ ATC – C GT – T TG 3’ 3’ TAG – G C A – AAC 5’ If this strict regulation is perturbed and the ratio of dUTP to dTTP rises, the amount of uracil that is incorrectly incorporated into DNA also increases. lems. The solution to this potential Why was uracil retained in RNA? The repair system – which, unlike problem is thought to have been the RNA is more short-lived than DNA DNA polymerases, can distinguish evolution of a mechanism in which and – with a few exceptions – is not uracil from thymine – then attempts ‘correct’ uracils (paired with adenine) the repository for long-term storage to cut out the uracil with the help were labelled with a methyl group – of genetic information, so cytosine of uracil-DNA glycosylase and to resulting in thymine. This way, if the molecules that spontaneously turn re-synthesise the DNA, which cell machinery found a uracil, it cut it into uracils in RNA do not present a involves temporarily cleaving out and repaired it, but if it found a great threat to the cell. Thus, there (cutting) the DNA backbone. uracil with a methyl label – a thymine was probably no evolutionary pres- However, if the ratio of dUTP to (see Figure 4) – it left it. Over time, sure to replace uracil with the more dTTP is still elevated, this re-synthesis therefore, thymine in DNA became complex (and presumably more cost- may again incorporate uracil instead the standard instead of uracil, and ly) thymine in RNA. of thymine. This cycle eventually most cells now use uracil only in RNA. leads to DNA strand breaks and chromosome fragmentation, when these Figure 7 Image courtesy of Angéla Békési temporary cuts in the DNA happen one after the other and too close to If dUTP:dTTP increases, DNA each other (see Figure 7). This results polymerase frequently incor- in a specific type of programmed cell porates uracil instead of High dUTP:dTTP death, called thymine-less cell death. thymine during both replica- DNA replication tion and repair. Uracil-DNA The process of thymine-less cell U U U death can be deliberately exploited in glycosylase removes the uracil DNA polymerase and initiates further repair U U the treatment of cancer. Because can- involving DNA strand breaks Uracil-DNA DNA cer cells proliferate at such a high rate in an intermediate step. Repair glycosylase repair compared to normal cells, they syn- synthesis, however, may rein- thesise a greater amount of DNA per troduce uracil, leading to a Chromosome fragmentation given time period and therefore futile DNA repair cycle. require large amounts of dUTP. By Eventually, the system is over- Thymine-less cell death loaded and chromosome frag- raising the ratio of dUTP to dTTP, mentation occurs, leading to U = Uracil these cancer cells can be selectively cell death targeted and eliminated.

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Image courtesy of cdascher / iStockphoto Uracil DNA still exists Although most cells use uracil for RNA and thymine for DNA, there are exceptions. Some organisms have uracil instead of thymine in all their DNA, and other organisms have uracil in only some of their DNA. What could be the evolutionary advantage of that? Let’s take a look at some examples.

Uracil in viral DNA Two species of phage (viruses that infect bacteria) are known to have DNA genomes with only uracil and no thymine. We do not yet know whether these phages are representa- tives of an ancient life form that never evolved thymine DNA, or whether their uracil-substituted genomes are a newly evolved strategy. Nor do we Artist’s impression of a phage virus infecting a bacterial cell know why these phages use uracil instead of thymine, but it may play an essential role in the life cycle of these viruses. If that is the case, it would Moreover, our own research has Beneficial errors: the vertebrate make sense for the viruses to ensure shown that, in larvae of the fruit fly immune system that the uracil in their DNA is not Drosophila melanogaster, the ratio of Uracil in DNA, however, can also replaced with thymine. And one of dUTP to dTTP is regulated in an be found closer to home – in the these phages has in fact been shown unusual manner: in all tissues that immune system of vertebrates like us. to have a gene that encodes a specific will not be needed in the adult insect, Part of our immune system, the adap- protein to inhibit the host’s uracil- there are much lower levels of the tive immune system, produces a large DNA glycosylase, thus preventing the enzyme that breaks down dUTP and number of different antibodies that viral genome from having its uracil generates a precursor for dTTP pro- are trained to protect us from specific ‘repaired’ by the host enzymes. duction. Consequently, significant pathogens. To increase the number of amounts of uracil are incorporated different antibodies that can be creat- Programmed cell death in insect into these tissues during DNA synthe- ed, we shuffle the DNA sequence in life cycles sis. the regions that code for them, not Uracil-DNA also appears to play a So during the larval stages, uracil- only by recombining the existing role in the development of endoptery- DNA is produced and seems not to be sequences in the cells but also by gotes – insects that undergo pupation corrected in tissues that are to be creating new ones through vastly during their life cycle (ants and but- degraded during the pupal stage. As increased mutation rates, known as terflies do; these insects lack the main uracil- hypermutation. grasshop- DNA glycosylase enzyme, at the Hypermutation starts with a specific pers and pupal stage, additional uracil-DNA- enzyme (an activation-induced deami- termites specific factors may recognise this nase) that changes cytosine into uracil

Image courtesy of taramol / iStockphoto do not). accumulated uracil as a signal to initi- (see Figure 4) at specific DNA loci, elic- These insects ate cell death. We have already identi- iting an error-prone repair response, lack the main fied an insect-specific protein that which the organism uses to its advan- gene for uracil-DNA seems to be capable of degrading tage: ‘errors’ generate new sequences glycosylase, which uracil-DNA, and we are investigating that can be used to make different would otherwise whether this enzyme is used to initi- antibodies. This system is very strictly remove uracil from ate programmed cell death. regulated, however, as if it got out of their DNA. hand, it would lead to cancer.

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Cutting-edge-science

When considering the question of received her PhD in structural bio- Since 2000, she has been the head of a why uracil or why thymine, we need chemistry from Eötvös Loránd laboratory focusing on genome to consider the evolutionary context. University of Sciences in 2007. She is metabolism and repair at the Institute Living organisms have evolved in a continuing her work as a postdoctoral of Enzymology, Budapest, Hungary. continuously changing environment, scientist, and was a school ambassa- The lab’s current research aims to facing a dynamic set of challenges. dor in the SET-Routes programme understand the prevention, recogni- Thus, a solution that avoids mistakes (www.set-routes.org/school/profiles/ tion and repair of uracil in DNA from being incorporated into DNA is bekesi_en.html). the perspectives of structural and cell advantageous to most organisms and Beáta G Vértessy was born in biology. most cells, which explains why Budapest, Hungary and was trained thymine-DNA became the norm. in the biological sciences. She has an Under certain circumstances, howev- MSc from the University of Chicago, To learn how to use er, ‘mistakes’ themselves can be bene- USA, a PhD / CSs from the Eötvös this code, see page 1. ficial, which is why some cells still Loránd University in Budapest, use uracil in their DNA. Hungary, and the Hungarian Academy of Sciences, and a DSc from Resources the Hungarian Academy of Sciences. To find out more about the work of Beáta Vértessy’s research group, see: www.enzim.hu/~vertessy To download a summary of Villő Muha’s PhD thesis, which was written under Beáta Vértessy’s supervi- sion and focuses on uracil-DNA in Drosophila melanogaster, use the link: http://teo.elte.hu/minosites/ The presence of uracil in anti- tezis2010_angol/v_muha.pdf body gene sequences elicits a The complete thesis is available here: DNA repair response, which has http://teo.elte.hu/minosites/ the effect of increasing antibody ertekezes2010/muha_v.pdf protein diversity. An extensive antibody pool increases the If you enjoyed reading this article, chance of the immune system why not take a look at the full col- recognising unwanted invaders lection of biology-related articles published in Science in School? See: www.scienceinschool.org/biology

Angéla Békési was born 1977 in Kaposvár, Hungary. In 2001, she grad- Image courtesy of taramol / iStockphoto uated in chemistry from the Eötvös Loránd University of Sciences, and in theology from the Pázmány Péter Catholic University (both in Budapest, Hungary), having joined the lab of Beáta Vértessy in 2000 as an undergraduate student. In 2001, she began a PhD on the regulation of uracil-DNA repair and uracil processing in pupating insects. She identified a new protein candidate for a novel type of uracil-DNA sensor and

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A neural switch for fear

Image courtesy of EM BL Ph oto lab

When something frightens us, should we freeze, or should we investigate? Sarah Stanley describes how scientists from the European Molecular Biology Laboratory are probing the mysteries of the brain, seeking to understand our response to fear. Image courtesy of EMBL Photolab

Cornelius Gross

lee, fight or freeze? For an animal overcome with fear, that is Fthe essential question. The answer often depends on the amygdala – a major emotion-processing hub nestled deep in the brain. In both mice and humans, it affects how we behave in response to certain types of fear, and helps to form long-term memories of frightening experiences. However, very little is known about how cells in the amygdala communi- cate with other brain cells to produce specific fear-induced behaviours. A recent study narrows this gap in knowledge, thanks to the innovative work of scientists at the European Molecular Biology Laboratoryw1 (EMBL) in Monterotondo, Italy, and GlaxoSmithKlinew2 in Verona, Italy. The scientists focused on one of many different types of fear processed by the amygdala. They used new tech-

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Cutting-edge-science

Image courtesy of EMBL Photolab niques to understand the interactions says Cornelius Gross, who led the between the areas of the brain research at EMBL. “It seemed that we involved in reactions to that specific were not blocking the fear, but just type of fear. In the course of their changing their responses from a pas- work, they identified a switch that sive to an active coping strategy. That toggles between two different fear is not at all what this part of the responses: freezing and, surprisingly, amygdala was thought to do.” an alternative to the flee, fight or To better understand the connec- freeze options, known as active risk tions between brain cells – the neural assessment. This active response circuitry – involved in the switch involves behaviours like rearing, from passive to active fear behav- digging and exploring. iours, the scientists looked at activity netic resonance imaging (fMRI). In Mice conditioned to associate a tone in different brain regions using a type small animals like mice, fMRI meas- with an uncomfortable shock usually of brain scan called functional mag- ures local blood volume as an indica- freeze in fear upon hearing the sound, even if it is not accompanied by discomfort. Neurons called type 1 cells, which are found in the amygdala, are known to control the freezing response. When type 1 cells are pre- Biology vented from sending signals to other Genetics cells, mice no longer freeze in fear. Pharmacology But, it seems, type 1 neurons are more Physiology than just an on / off switch. Behaviour In a pioneering approach that uses both pharmacology and genetics, Ages 16+ EMBL scientists engineered mice so that their type 1 cells could be turned In this article, several experiments are carried out with mice (in off without disrupting other cells. The which both the behaviour and the activity of the brain were mice were made to produce certain analysed) to understand the details of their response to fear. Such drug-sensitive proteins (receptors) research is very important to ultimatly improve our knowledge exclusively in their type 1 cells. When about how the human brain works. the mice were injected with the drug, This article can be extremely useful for giving students some insight it bound to those receptors, setting off into how research is done in scientific laboratories. Teachers can get chemical reactions that disrupted the their students to read the article and then think about how respond cells’ electrical charge. Thus, these to fear, perhaps even designing and performing an experiment. neurons could no longer send electri- Furthermore, students can think about the evolutionary benefits of cal signals to surrounding brain these reactions for our ancestors, and how useful they are in mod- regions. ern life. Moreover, the students can try to find out about animals Before treatment with the drug, the with different responses to fear and try to relate their behaviour to mice had been conditioned to fear a their environment. certain tone. After their type 1 cells The use of new research techniques such as pharmacogenetics and were blocked, they were subjected to functional magnetic resonance imaging (fMRI) is also reported in the tone, and their behaviours were this article. Students aged 16 and over can try to find more informa- observed and analysed. tion about how these techniques work and their importance in “When we inhibited these neurons, research. I was not surprised to see that the Finally, this article could also be used as a starting point for dis- mice stopped freezing, because cussing research on animals. Students can think about how the [freezing] is what the amygdala was results obtained from animals can be applied to humans, and they thought to [control]. But we were can also discuss alternatives to animal testing. very surprised when they did a lot of Mireia Guell Serra, Spain other things instead, like rearing and REVIEW other risk-assessment behaviours,”

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Image courtesy of Nicola Graf, Cornelius Gross and Marlene Rau

A When mice hear a tone that they have been conditioned to Cortex associate with an uncomfortable shock, the amygdala is Conditioned tone activated and relays information Cholinergic to the brainstem, making the basal forebrain animal freeze (A). neurons However, in mice in which type 1 amygdala neurons have been switched off, these neurons no longer suppress the surrounding Freezing type 2 amygdala cells. Type 2 behaviour neurons now activate the cortex via the cholinergic basal fore- Amygdala brain, blocking freezing and Type 1 neurons active Brainstem promoting risk-assessment Type 2 neurons blocked instead (B)

tor of brain activity: the more blood capable of displaying fear behaviour, external threats, the amygdala makes there is in a particular area of the the scientists took a different decisions about how to respond. brain, the more active those neurons approach. They used the drug It is important to note that the type are. This study marks the first use of atropine to block cortex activity in of fear explored in this study – condi- fMRI to map neural circuitry in mice, mice whose type 1 cells were blocked, tioned fear of a painful shock – is using a new technique developed by and found that the animals no longer very specific. The results cannot nec- GlaxoSmithKline scientist Angelo showed any risk assessment behav- essarily be applied to behavioural Bifone and his team. iours. responses to other types of fear in The brain scan yielded another Thus, the scientists infer, the amyg- mice. unexpected result. Scientists previous- dala normally inhibits the cholinergic “There are multiple, parallel fear ly thought that the amygdala man- basal forebrain, while it signals the circuits that handle different types of aged fear behaviours by simply relay- brainstem to control the passive fear fear information. For example, one ing information to the brainstem, response: freezing (see image above, part of the [mouse] brain is often used which links the brain to the spinal A). When type 1 neurons are blocked, to process fear of a predator, such as a cord. But Cornelius, Angelo and their however, the amygdala releases its cat, while another part usually colleagues found that in mice with hold on the cholinergic basal fore- responds to aggressive behaviour by blocked type 1 cells, the outer layer of brain, leading to cortex activity and another mouse,” Cornelius says. “We the brain – the cortex – was highly an active reaction to fear: risk assess- thought there was a simplistic fear active, indicating that it too plays a ment (see image on page 35, B). circuit that is either on or off, but that role in determining how mice react to “This is a powerful demonstration doesn’t seem to be true.” fear. Activity was also observed in a of the ability of functional MRI to Also, scientists are not yet sure region of the brain called the choliner- resolve brain circuits involved in com- whether wild mice ever use risk gic basal forebrain, which is known to plex tasks, like processing of emotions assessment behaviours in response to influence cortex activity. and control of behavioural respons- threatening stimuli. Blocking of type 1 Like all brain scans, fMRI requires es,” says Angelo, now at the Italian cells was performed artificially in this the subject to remain very still, so it Institute of Technologyw3 in Pisa. study, and there may or may not be can only be performed on mice that Taken together, the results of the situations when the neurons would have been anaesthetised. But the sci- array of techniques used to explore naturally be inhibited, leading the entists wanted to confirm the associa- the freezing fear response in mice mouse to engage in investigative tion between the cortex and fear indicate that the amygdala plays a behaviours to learn more about a per- behaviours in conscious mice. As they more complex role in fear processing ceived threat. could not observe brain activity while than previously thought. Instead of If the active response is found natu- the mice were awake and therefore merely passing on information about rally in mice, what kinds of external

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Cutting-edge-science

Resources B For an introduction to the 2010 article Conditioned tone by Gozzi et al., see: Pape HC (2010) Petrified or aroused Cortex with fear: the central amygdala takes the lead. Neuron 67(4): 527- 529. doi: 10.1016/j.neuron.2010.08.009 Cholinergic As part of an exhibition (Goose basal forebrain neurons Bumps! The Science of Fear), the Museum of Science, Boston, USA, devised some scary activities for the classroom. See the museum's website (www.mos.org) or use the direct Brainstem Amygdala link: http://tinyurl.com/65savzz Risk assessment Type 1 neurons active For another example of research using behaviour Type 2 neurons blocked fMRI, see: Hayes E (2010) The science of humour: Allan Reiss. Science in School 17: 8-10. www.scienceinschool.org/2010/ sensory cues are necessary to activate though they have normal reactions to issue17/allanreiss it? Previous studies have shown that fear in other situations. Thus, it is If you enjoyed this article, you may animals located farther away from a likely that the results of this study like to browse the other cutting- perceived threat are more likely to could apply directly to humans, edge science articles in Science in freeze in fear than run or fight. But Cornelius says. School: www.scienceinschool.org/ scientists cannot yet say whether use Though much remains to be discov- cuttingedge of an active risk assessment response ered about how humans process fear is a function of distance. Cornelius in different situations, studying fear emphasises that it is important not to brings scientists ever closer to devel- assume that risk assessment would be oping more effective treatments for Sarah Stanley graduated in biology used in place of freezing in a situation fear-based illnesses – such as anxiety from the University of California, perceived as less threatening. disorders and post-traumatic stress Santa Barbara, USA. At the time of

Nonetheless, the study has signifi- disorder. In the words of two-time writing this article, she was a science Image courtesy of EMBL Photolab cant implications. The pharmacoge- Nobel Prize-winning chemist Marie writing intern at the European netic and fMRI techniques used by Curie, “Now is the time to under- Molecular Biology Laboratory. the scientists will likely prove invalu- stand more, so that we may fear less.” Currently, she is an intern at Discover able in many other studies of neural Magazine. References circuits in mice. Indeed, Cornelius and his team have already used a Gozzi et al. (2010) A neural switch for pharmacogenetic approach to reveal active and passive fear. Neuron cells that act as an input for another 67(4): 656-66. doi: 10.1016/ brain region, the hippocampus, relay- j.neuron.2010.07.008 ing information that enables a mouse Web references to gauge an appropriate level of anxi- w1 – To learn more about the ety in an uncomfortable circumstance. European Molecular Biology Furthermore, we humans also show Laboratory (EMBL), see: freezing and risk assessment respons- www.embl.org es to fear. We possess a region of the w2 – For information about amygdala that is analogous to the one GlaxoSmithKline in Verona, Italy, housing the active / passive switch in see: www.gsk.it mice. Patients who have suffered w3 – To find out more about the lesions to this region are unable to Italian Institute of Technology, see: To learn how to use develop conditioned fear responses, www.iit.it this code, see page 1.

www.scienceinschool.org Science in School Issue 18 : Spring 2011 35 sis_18_RZ_.qxq:Layout 1 15.03.2011 18:17 Uhr Seite 36 Image courtesy of aristotoo / iStockphoto The resourceful physics teacher Physics teacher Keith Gibbs shares some of his many demonstrations and experiments for the physics classroom.

uring more than 30 Boiling water under reduced · A retort stand and clamp years of teaching pressure A safety screen physics, I have come · D Age range: 13-15 · A tray across many interesting demon- This simple experiment Water strations and teaching ideas – demonstrates that the saturated · often suggested by relatives, vapour pressure of water Procedure friends, colleagues and past stu- depends on the temperature. It is 1. Fit the rubber tube onto the dents. In 2000, I began to gather best performed as a teacher end of the glass tube. these ideas together – this was demonstration, with a safety 2. Fit the thermometer and glass the basis of the Schoolphysics screen between the apparatus tube into the holes in the website and CD-ROM collection. and the students. bung, pour cold water into the Over time, I added more expla- flask until it is just less than nation and background for teach- Materials half full. Then seal the flask ers whose specialism was not A round-bottomed flask · with the bung. physics. A bung with two holes · 3. Fit the clamp onto the rubber Below are four ideas from the · A glass tube, with an external tube but do not close the collection. I hope that you will diameter to fit the hole in the clamp. find at least one of them new, bung challenging, informative and fun, · A rubber tube with a diameter and that the ideas go some way to connect to the glass tube towards popularising the subject A thermometer to fit the hole and making people realise that · in the bung physics can be interesting and A Bunsen burner fun. ·

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Teaching activities

Physics else while the theory is being explained, to consoli- Chemistry date concepts with facts. A discussion can be held Thermodynamics with students during the experimental investigations to prompt them to make predictions and explain the Circular motion outcomes. Electromagnetism The activities can be used with students of different Gravitational fields ages, depending on the emphasis. The boiling water Inertia activity could be used with students aged 13-15 to dis- Boiling points cuss the boiling point of water; for students aged 16- Ages 13-19 19, it could be used in a lesson about gas laws. The coat-hanger experiments could be used with 16- to The four experiments described in this article are 18-year-olds to introduce circular motion, centripetal innovative and use items that are easily available in force and centripetal acceleration. For 10- to 13-year- school laboratories. The aim, materials, procedure and olds, the electromagnetic separator activity could be diagram for each experiment make it very straightfor- used in general science lessons or to discuss magnet- ward for teachers and students to understand the ic materials; for students aged 14+, it could be used in processes and theories involved. It is also interesting magnetism lessons. Finally, the experiment with the to read about the author’s experiences and the results falling jar could be used for students aged 16+ to teach that he obtained from these experiments. simple harmonic motion, gravitation and inertia. Teachers could use the experiments for a wide array of These types of demonstration are ideal for students physics topics and adapt them to different age groups, who are visual learners and who will understand and depending on how much theory the teacher chooses remember theory better when they see it applied in to explain. They can be performed as a pre-topic practice. experiment to introduce the students to the theory or Catherine Cutajar, Malta REVIEW

4. Use the Bunsen burner to heat the See also the general safety note on Temperature Saturated vapour water to boiling. the Science in School website pressure 5. Close the clamp and turn off the (www.scienceinschool.org/safety) 37 °C 0.06 x 105 Pa Bunsen burner. and on page 65. 60 °C 0.19 x 105 Pa 6. Invert the flask and pour cold Theory 5 water over it. 75 °C 0.38 x 10 Pa The explanation is that the saturat- 85 °C 0.57 x 105 Pa Steam will condense inside the ed vapour pressure of water depends 5 flask, reducing the pressure and on the temperature: the lower the 100 °C 10 Pa allowing the water to start boiling temperature, the less water vapour Table 1: Dependence of saturated vapour again. When the water stops boiling, the air can hold (see Table 1). When pressure of water on temperature pour more water over the flask. How the water condenses, it lowers the low can you get the temperature and pressure in the flask – and this, of still observe the water boiling? You course, allows water to boil at less should be able to get the water to boil than 100 °C. Image courtesy of Keith Gibbs at 40 °C – I once observed the water boiling at body temperature (37 °C)! An alternative method Safety note: wear safely goggles. A simpler method is to partly fill Although unlikely, it is possible that (about 20%) a syringe with 50-60 °C the glass flask could shatter, so keep a warm water. Then pull on the plunger safety screen between the experi- of the syringe. This lowers the pres- ments and the students. If possible, sure in the syringe, causing the water stand behind the screen yourself. to boil at well below 100 °C.

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Image courtesy of Floortje / iStockphoto

3. Balance a small coin (try · An AC (alternating current) power a UK one-penny piece or a supply 5 or 10 Euro-cent coin) on the hook. · Aluminium scraps (e.g. kitchen foil) 4. Place one finger in the corner of the A piece of thin card square opposite the hook and spin · The wire coat hanger and Some scraps of paper circular motion the coat hanger in a vertical circle. · The coin should remain in place. Procedure Age range: 14-18 1. Place the card on top of one arm of This is a simple demonstration of Theory the electromagnet and put a few centripetal force. The force of the hook on the coin provides the centripetal force, and scraps of aluminium and paper Materials this always acts towards the centre of onto the card. · A wire coat hanger with the end rotation. 2. Connect the electromagnet to an filed to a point How many coins can you balance AC supply and turn on the current. · A metal file on the swinging coat hanger? My The aluminium scraps will be eject- · A small coin record is five one-penny pieces. With ed from the magnetic field. only one penny and with great care, I

Procedure Image courtesy of Keith Gibbs have once even been able to bring the 1. Bend the wire coat hanger until it coat hanger to rest without the coin forms a square. falling off. 2. File the tip of the hook flat and then bend the hook until it points Electromagnetic separator towards the opposite corner of the Age range: 16-18 square (see diagram). This is a small-scale simulation of Image courtesy of Keith Gibbs the type of electromagnetic separator Theory that is used industrially to separate The AC electromagnet induces non-ferrous metals from other non- eddy currents within the aluminium metallic scrap, and is suitable as a scraps. These turn the scraps into tiny teacher demonstration. electromagnets that are then repelled Materials by the large electromagnet and so fly · A U-shaped electromagnet with an off the card. With non-metallic scraps iron core to give a high field inten- there are no induced currents and so sity these scraps remain on the card. In a moving-belt version of this Fairground ride-goers experiment, mixed metal and non- should be grateful to metal scraps are passed along a belt Im age c centripetal force over an AC electromagnet. This our tes y o f i induces eddy currents in the metal na be an p scraps, which are then repelled by the o d ; im field and fly off sideways while the a g e remaining non-metal scraps continue s o u r c along the belt. Schools might be able e :

F l i to construct such a version for c

k r demonstration use, using a mixture of paper and aluminium. A floating block in a falling jar Age range: 11-18, depending on the treatment of the theory. This is a very useful demonstration of one of the ideas of general relativity, using a wooden block floating in a jar of water that is suspended from a spring.

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Teaching activities Image courtesy of ZargonDesign / iStockphoto

Theory Resources The depth at which the wooden If you enjoyed this article, you block or straw floats depends on both might like to browse the rest of the its weight (not its mass) and the teaching activities on the Science in upthrust on it. The upthrust depends School website. See: on the weight of water displaced. www.scienceinschool.org/teaching Thus, as the acceleration of the jar If you prefer to concentrate on Artist’s impression of a large electromag- and the block changes, the weight of physics, here is a list of all physics- net, of the type used for separation in an the block and the upthrust on it related articles in Science in School: industrial setting change in direct proportion to each www.scienceinschool.org/physics other; as a result, the depth at which Materials the block floats remains unchanged as · A helical spring tied with string the apparatus oscillates. After graduating from University to a plastic jar Objects undergoing acceleration College London, UK, with a degree in · A wooden block or straw loaded behave in the same way as they physics, Keith Gibbs took a PGCE with modelling clay (e.g. Plasticine®) would in a gravitational field. As the teacher training course at Cambridge · Water jar and its contents oscillate, they University, UK. He subsequently have an acceleration that is due to Procedure taught physics in four different Image courtesy of Keith Gibbs both the constant schools across the UK for 36 years, 1. Half fill the jar with water, add the gravitational field retiring in 2002. wooden block or straw, and sus- of Earth and the The ideas in this article are just a pend the apparatus from the simple harmonic spring. few of more than 700 ideas and exper- motion of the iments that Keith Gibbs has collected 2. Support the jar, then let it fall, sus- oscillation. and devised over the years, available pended from the spring. The jar As the jar on CD-ROM (currently £10). These, as and contents will then oscillate in a moves upwards, well as explanations suitable for vertical plane (up and down) but its net accelera- 11- to 19-year-old students, anima- the water level will stay at the tion is greater tions, lesson plans, images and much same position in the jar and the than that of more, are available on a further CD- block or straw will float at the Earth’s gravita- ROM which, once bought (currently same level in the water as it falls tional field and as £35), can be copied within the school and rises. it falls, its acceleration is less than that and made available via the school’s

Image courtesy of Ute Kraus; image source: Wikimedia Commons of Earth’s field. On the downward intranet. See the Schoolphysics web- part of the motion, it is as if the jar sitew1. were on the Moon, where the gravita- Keith has written and contributed tional acceleration is less than on to a number of physics textbooks. Earth. Recently, he has worked with Pearson This is a very useful demonstration Education on animations for of the equivalence of gravitational advanced-level physics courses, and and inertial fields. practical projects for younger physics students. Acknowledgements Keith also travels extensively, The editors of Science in School demonstrating his collection of exper- would like to thank Catherine Cutajar iments. If you are interested in a visit, and Gerd Vogt for their help in select- Computer-simulated image of the night contact him via the Schoolphysics ing the experiments to include in this sky, were it to feature a black hole with a websitew1. mass ten times that of the Sun, and seen article. from a distance of 600 km. Einstein’s theory of general relativity allows details of Web reference To learn how to use a black hole’s structure to be calculated. w1 – To view more (free) teaching this code, see page 1. Black holes are thought to be distortions material collected by Keith Gibbs or in space and time, consisting of zero vol- to purchase the CD-ROMs, see: ume and infinite density. www.schoolphysics.co.uk

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Breeding dragons: investigating Mendelian inheritance

Mendelian inheritance can be a tricky topic to teach, but

Pat Tellinghuisen, Jennifer Image courtesy of julos / iStockphoto Sexton and Rachel Shevin’s memorable dragon-breeding game makes it easier to understand and remember.

Biology type and phenotype, dominance, meiosis and breed- Ages 10-15 ing) in a novel and playful way. The activity could be carried out very easily in the classroom with practi- cally no equipment. As a secondary-school biology teacher I had never Suitable comprehension questions include: come across the idea of teaching genetics using mythical creatures, but after my initial surprise, I 1) Dragons have: realised that using the genetics of dragons was per- a) seven chromosomes fectly coherent with the scientific facts... and really b) seven genes good fun! The idea of randomly choosing genes and c) seven pair of chromosomes looking for the resulting traits of baby dragons is ingenious and effective at the same time. d) seven alleles. Even if they aren’t real, dragons can help to raise 2) When you breed dragons, the number of chromo- interest in a topic generally considered boring (at somes of their offspring: least by students) and can convey scientific concepts a) is divided into half as well as real organisms like Mendel’s peas do. b) remains the same I recommend this article to primary- and lower-sec- c) is doubled ondary school biology teachers willing to address the d) depends on their sex. basics of Mendelian genetics (genes, alleles, geno- Giulia Realdon, Italy REVIEW

Image courtesy of Alexsey / iStockphoto

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Teaching activities

ragons may be mythical ani- Image courtesy of Darryl Leja, NHGRI / NIH mals, but they can still be Dgood tools for investigating Mendelian inheritance. In the follow- A gene ing activity, students will ‘breed’ baby dragons, using paper chromosomes to Deoxyribonucleic Acid (DNA) determine the genotype and pheno- A a Image courtesy of Nicola Graf type. The activity has been tested with students aged 12-13, and generally takes one lesson – about 45 to 60 minutes. Chromosome Materials For the whole class How DNA is packaged into Different alleles of the same · A DNA model chromosomes (not to scale) gene (not to scale) · A picture of a chromosome For each student could have in your herd when (or if) half from the ‘mother’. For example, · A set of chromosome strips in two your two dragons decide to mate. in plants, a pollen grain is the pater- colours (14 pink strips for the nal contribution and an ovule is the mother and 14 blue strips for the Background for the students maternal contribution. These two cells father) Each cell in all living organisms combine to make a single cell, which · A student worksheet contains hereditary information that will grow into a seed (the offspring). · Crayons (at least four colours) is encoded by a molecule called Humans have 46 chromosomes, sorted into 23 pairs. One chromosome The chromosome strips, Tables 1-3 deoxyribonucleic acid (DNA): show in each of the 23 pairs is from the per- from the worksheet and the basic students the DNA model. DNA is an son’s father, the other from his or her dragon drawing can be found on extremely long and skinny molecule, which when all coiled up and mother. Since chromosomes come in pages 42/43 or downloaded from the bunched together, is called a chromo- pairs, genes do too. One gene is locat- Science in School websitew1. some: show students the picture of a ed on one member of the chromo- Procedure chromosome. Each chromosome is a some pair; the other gene is in the Using the information below, intro- separate piece of DNA, so a cell with same location on the other chromo- duce the dragon story and the eight chromosomes has eight long some. The gene ‘pair’ is technically required background for the activity to pieces of DNA. referred to as a ‘gene’, as both mem- the students. Then hand out the mate- A gene is a segment of the long bers of the pair encode the same trait. rials and let the students follow the DNA molecule. Different genes may For any gene, a variety of different instructions on the student worksheet. be different lengths and each gene is a forms – known as alleles – may exist, Tables 1–3 can also be downloaded code for how a certain polypeptide but each person can have a maximum from the Science in School websitew1. should be made. One or more of only two alleles (one from the polypeptides form a protein, which mother, and one from the father). The The story can generally be sorted into two dif- two copies of the gene that a person Dragons are a curious type of crea- ferent types: those that run the chemi- has may be the same or different alle- ture. Amazingly, though, their genet- cal reactions in your body (enzymes), les. ics is very similar to that of humans – and those that are the structural com- Our dragons have 14 chromosomes or even guinea pigs. Many schools ponents of your body (structural pro- in seven pairs, and we will look at keep pet guinea pigs, but wouldn’t it teins). How an organism looks and only one gene on each of the pairs. be much more exciting to keep a herd functions is a result of the cumulative We will be investigating seven differ- of dragons? Unfortunately, dragons effect of both these types of protein. ent traits (e.g. the ability to breathe are very expensive, so your school Any organism that has ‘parents’ has fire), each of which is controlled by a can only afford two – one of each sex. an even number of chromosomes, single gene – we say that such a trait The purpose of this activity is to because half of the chromosomes is monogenic. Each of the seven genes determine what kinds of dragon you come from the ‘father’ and the other has two alleles.

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Student worksheet

One set of 14 strips represents the chromosomes from 3. Without turning the chromosomes over, pick one of the mother (female) dragon. The other, differently each colour and put them together to form the chromo- coloured set, represents the chromosomes from the father some pair for the baby dragon. Discard the remaining (male) dragon. pair of chromosomes. Each chromosome strip has a letter, which may be either 4. Repeat steps 2 and 3, moving from the longest to the upper or lower case. The upper-case letters represent shortest chromosomes, until you have seven new chro- dominant alleles, and the lower-case letters represent mosome pairs, each consisting of one pink and one recessive alleles. Each pair of letters codes for a trait. If at blue strip. least one dominant allele (upper-case letter) is present, the 5. Turn over the seven pairs of chromosomes of the new dominant trait will occur (e.g. the dragon can breathe fire); baby dragon. For each pair, record the letter on the blue the recessive trait (e.g. inability to breathe fire) will only chromosome in the ‘Male gene’ column in Table 1 and occur if the dragon has two copies of the recessive allele. the letter of the pink chromosome in the ‘Female gene’ 1. Sort the chromosomes so that they are matched into column. Be sure you copy the letters exactly, noting pairs of the same length and letter of the alphabet. You whether they are upper or lower case. should have seven chromosome pairs for each colour (blue for male, pink for female). 6. Return all the chromosomes to their proper bags. The traits encoded by the letters are as follows: 7. Record which alleles (letters) your dragon has for each · F and f represent whether or not the dragon trait, and enter them in the second column of Table 2. breathes fire We refer to the two alleles inherited for a particular · M and m represent the number of toes gene as the genotype (e.g. TT). The observable traits of · S and s represent the number of tail spikes an individual (e.g. a red tail) are known as the phenotype. · T and t represent the colour of the tail 8. Refer to Table 3 to determine which alleles are domi- · A and a represent the colour of the body nant or recessive for each trait, then enter the pheno- · W and w represent the colour of the wings type of your dragon in Table 2. · H and h represent whether or not the dragon has a 9. Now you are ready to draw your baby dragon: colour horn. and add the relevant body parts to the basic dragon 2. Take the longest pair of male chromosomes (blue) and picture (which can also be downloaded from the Science the longest pair of female chromosomes (pink) and in School websitew1). See Table 3 for suggestions as to place them face down on your desk so that you cannot how the additional body parts can be drawn. see the letters.

A a A a

H h H h

W w W w

T t T t

S s S s

M m M m

F f F f

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Teaching activities

Male gene Female gene Trait Genotype Phenotype (blue) (pink) Fire/No fire (F/f)

Toes (M/m)

Spikes on tail (S/s)

Tail colour (T/t)

Wing colour (W/w)

Horn/no horn (H/h)

Body colour (A/a)

Table 2: Genotype and phenotype of your baby dragon

Table 1: The genes your dragon has inherited from its parents

Genotype Phenotype

FF or Ff Breathes fire

ff Does not breathe fire

MM or Mm Four toes

mm Three toes (all dragons have at least three toes)

SS or Ss Five spikes on tail The basic dragon ss Four spikes on tail picture (all dragons have at least four tail spikes)

TT or Tt Red tail

tt Yellow tail

WW or Ww Red wings

ww Yellow wings

HH or Hh Horn

hh No horn

AA or Aa Blue body and head

aa Green body and head

Table 3: Translating the dragon genotype into the phenotype

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Variations Acknowledgements 53-58. www.scienceinschool.org/ 2009/issue13/insight Codominance This activity is based on an idea by Patti Soderberg, adapted with permis- For our two-part article on molecular To introduce the concept of codomi- sion from The Science Teacher (see evolution and the genetics behind nance, you can extend the activity by Soderberg, 1992). Her reebops lesson positive selection of certain alleles, swapping the relevant materials con- was then adapted by the authors. see: cerning the body colour trait (geno- Credit for the chromosome strips goes Bryk J (2010) Natural selection at type Aa) for the following ones with to Nancy Clarkw2, and Marlene Rau, the molecular level. Science in School the genotypes A/Ä/a, where A and Ä editor of Science in School, included 14: 58-62. www.scienceinschool.org are codominant and a is recessive: the codominance example. /2010/issue14/evolution Bryk J (2010) Human evolution: Genotype Phenotype References testing the molecular basis. Science AA or Aa Blue body and head Soderberg P (1992) Marshmallow in School 17: 11-16.www.scienceinschool. meiosis. The Science Teacher 59(8): 28- org/2010/issue17/evolution ÄÄ or Äa Black body and head 31. The article can be freely down- Staying with the subject of genetics AÄ Stripy blue and black loaded from the Science in School web- and evolution, a simple way to body and head site, with kind permission from The teach the Hardy-Weinberg principle Science Teacher. See: aa White body and head in class is described here: www.scienceinschool.org/2011/issue 18/dragons#resources Pongsophon P et al. (2007) Table 1a: Translating the dragon genotype Counting Buttons: demonstrating into the phenotype (extension for codom- Web references the Hardy-Weinberg principle. inance example) w1 – The chromosome strips, tables Science in School 6: 30-35. and the basic picture for this activi- www.scienceinschool.org/2007/ Trait Genotype Phenotype ty can be downloaded from the issue6/hardyweinberg Science in School website. See: Try the UK Science museum’s online Body colour www.scienceinschool.org/2011/ game ‘Thingdom’ to learn about (A/Ä/a) issue18/dragons#resources genetics while creating your own Table 2a: Genotype and phenotype of w2 – Retired US science teacher fictional organism. See: your baby dragon (extension for codomi- Nancy Clark’s collection of class- www.sciencemuseum.org.uk/ nance example) room resources can be found online: WhoAmI/Thingdom.aspx www.nclark.net If you enjoyed this article, why not Chromosome set 1 w3 – Find out more about the browse our full collection of biology Vanderbilt Student Volunteers for articles? See: For the father A Ä Science here: http://studentorgs. www.scienceinschool.org/biology vanderbilt.edu/vsvs For the mother A Ä Resources Patricia Tellinghuisen is the Director Chromosome set 2 The Scottish ‘Gene jury’ project proof the Vanderbilt Student Volunteers w3 poses a ‘make a baby’ game, focus- for Science (VSVS) and Faculty For the father a Ä ing on pre-implantation diagnostics Advisor at Vanderbilt University, and genetics. See the Gene jury Nashville, Tennessee, USA. Jennifer For the mother A A website (www.biology.ed.ac.uk/ Sexton and Rachel Shevin were projects/GeneJury) or use the direct undergraduate laboratory assistants link: http://tinyurl.com/6edlhnq at the VSVS. Other variations To learn more about genetic diseases, Instead of drawing dragon parts, and the research into them, see: you could have your students draw To learn how to use Patterson L (2009) Getting a grip on this code, see page 1. other mythical creatures, or even genetic diseases. Science in School 13: build them, for example from marsh

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The heat is on: heating food and drinks with chemical energy

Have you ever longed for a hot drink or meal but had no fire or stove to hand? Marlene Rau presents two activities from the Lebensnaher Chemie- unterricht portal that use chemical reactions to heat food – and to introduce the topic of exothermic reactions.

Image courtesy of Martin Müller / pixelio

Heater meals meal system, which relies on the reac- Therefore, in the heater meal, iron is tion of magnesium and salt water to Heater meals – originally developed added to the magnesium, leading to produce hydrogen: for military use – are ready-made self- the production of a local cell – small- 2+ Mg (s) + 2H2O (l) -> Mg (aq) + H2 (g) scale corrosion that happens where heating meal packs. They can be heat- - + 2OH (aq) two metals of different reactivity are ed in many ways – by pressing a but- s: solid; l: liquid; g: gaseous; aq: in in contact under humid conditions – ton on the packaging, unwrapping solution; the vertical arrow indicates which speeds up the exothermic reac- and shaking the pack, or pouring the that gas is released. tion. Because the electron potential of contents of one bag into another and This reaction is very slow, due to magnesium is lower than that of iron waiting for a few minutes – all of passivation, so to speed it up, iron (the less reactive metal), electrons will which use exothermic chemical reac- and salt are added. Passivation is the pass from the magnesium to the iron, tions. These meals can be used to moti- process by which a material is made and only from there into the water. vate students to study such reactions less reactive, usually by the deposi- Although magnesium cations (Mg2+) relatively safely and without the use of tion of a layer of oxide on its surface: and hydroxide anions (OH-) continue a burner. Plus there is the added value if you place a strip of magnesium into to be formed, they are separated by of discussing the negative ecological cold water, its surface will oxidise to the iron and cannot combine to form aspects of disposable meals. magnesium hydroxide (Mg(OH)2), magnesium hydroxide. As a result, For the following experiment, we and this coating will prevent further the magnesium does not become pas- use the Crosse & Blackwell heater- reaction. sivated by a coating of magnesium

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Science education projects

Images courtesy of Gregor von Borstel

The heater-meal pack: the meal (silver bag), heater bag into which the meal is placed (orange), salt-water bag (see-through), magnesium/iron mixture (white bag, taken out of the orange bag), spoon

hydroxide, which would lower the · A heat-resistant glass · A 50 ml syringe reactivity. · A laboratory thermometer · 10 ml saturated sodium chloride Because the differently charged solution magnesium and hydroxide ions are Materials per group A 20 ml syringe mobile, in pure water they would · An empty tea bag · A three-way stopcock soon form magnesium hydroxide, the · A small amount (a few grains, cov- · charge would be equilibrated and the ering the tip of a spatula) of the · A small beaker reaction would slow down again. To magnesium / iron powder mixture · A plastic tube fitting on the valves prevent this, sodium chloride is taken from a Crosse & Blackwell of the stopcock (about 10 cm long) added to the water, so that the sodi- heater-meal pack. Mixing magne- · A bowl filled with water um (Na+) and chloride (Cl-) ions from sium and iron powder yourself A burning candle the salt can move to the magnesium tends not to work since it is already · A test tube and hydroxide ions instead, equili- partly oxidised. The powder mix- · brating the charge. ture in the heater meal packs is · Phenolphthalein solution <1% per The experiment can be used to vacuum-sealed. weight introduce and discuss the topics of electron transfer, local cell, passivation, sacrificial anodes, corrosion and the composition of water (covalent bonds, polarity and oxidation numbers). It takes about 45 minutes plus Chemistry discussion time and has been success- General science fully tested with 14-year-olds to study Energy electron transfer reactions and corro- Ages 8-19 sion, as well as with older students to work on electrochemistry. This article allows students to discover the link between classroom science and the real world. With experiments that have a wow fac- Materials tor – often missing from practical lessons – students can develop Demonstration materials and build skills and knowledge. · A magnesium strip The main subject addressed is chemistry, but the teacher could · Cold (unheated) saturated sodium adapt the lesson to include discussions of energy from other sub- chloride solution (salt water) jects, for example keeping warm, survival in cold climates, and · Phenolphthalein solution treatment of sports injuries. The experiments could also be used to · A Crosse & Blackwell heater-meal trigger a discussion of how science works.

pack (available from a range of REVIEW Nick Parmar, UK suppliers)w1

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Images courtesy of Gregor von Borstel

A closed and an open three-way stopcock

The plastic materials required for the experiment can 7. Before starting, demonstrate how to perform the oxy- be ordered as part of the ChemZw2 kits, which were hydrogen test: hold the top of a test tube close to a developed in collaboration with the Lebensnaher flame, allowing the gas in the tube to combust. There Chemieunterricht (LNCU)w3 project, but are also available are two possible positive results: from most medical and chemical lab suppliers. a) If the tube contains both hydrogen and oxygen, the hydrogen will combust with a ‘squeaky pop’. Under Procedure normal lab conditions, this is the usual result, as the 1. Show a film about the heater mealw4. tube will also contain oxygen from the air. 2. Show the heater meal to the students. b) If the tube is completely filled with hydrogen, there 3. Pour the contents of the heater-meal pack into a heat- will be no sound, but the gas combusts with colour- resistant glass with a thermometer and observe the less flame and the resulting water will fog the test reaction – it heats up and bubbles are produced. tube. Furthermore, the exothermic reaction will heat Note: if you use the contents of only two of the four the tube. Students often mistake this for a negative result (no hydrogen). packages of magnesium / iron mixture, you can save the contents of the other two for the students’ experi- 8. Place the students into groups of three to perform the ments – it will be sufficient for about 20 student heater-meal experiment. Because of the resulting heat, groups. Even with only two of the packages for the the reaction speeds up, so should only be performed demonstration, the heater meal will reach a tempera- on a small scale (as suggested). ture of 100 °C after about one minute. At the local cell, magnesium hydroxide is produced. If 4. Discuss: why does this work? What is happening? desired, this can be detected using phenolphthalein What kind of gas is produced? (see below). 5. Explain the reaction of magnesium – ignore the iron 9. Hand out the worksheet (see page 49 or download it w5 and salt for the moment. from the Science in School website ) describing how to carry out the heater-meal experiment. The students 6. Demonstrate that a magnesium strip shows a weak will now be ready to start. reaction with cold saturated salt solution (which is what is added in the heater meal): a few gas bubbles are visible, and adding a droplet of phenolphthalein solution gives a light pink colour.

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Science education projects

Student worksheet

Safety note: Wear safety goggles. The reaction creates the gas that is produced pushes the piston out of the highly flammable gas – be careful. See also the general syringe. safety note on the Science in School website 5. Once you have released the water, close the valve to (www.scienceinschool.org/safety) and on page 65. keep the gas in the syringe, and attach the plastic tube 1. Put the metal powder mixture into an empty tea bag to the valve. If gas continues to be produced, leave the and stuff this into a 50 ml syringe (without the tea bag, valve open. the powder could block the syringe). Press out the air. 6. Press the piston of the syringe to push the gas into a 2. Fill the 20 ml syringe with salt water and connect it to test tube through a pneumatic trough (use the plastic the large syringe using a three-way stopcock. tube, bowl of water and test tube as in the diagram). 3. Turn the stopcock’s valve to let the two materials flow 7. Perform the test for hydrogen by holding the mouth of together in the closed system. the test tube in a flame (see diagram below), making As the reaction proceeds, gas will collect in one of the sure you hold the top of the tube close enough to the syringes. flame. The test should be positive. 4. As soon as more than 25 ml of gas has collected, open Optional: add one droplet of phenolphthalein solution to the stopcock and let the salt water flow out, collecting it the water you collected in the beaker. What happens? in a beaker. Why? Safety note: because of the resulting heat, the reaction Health and safety note: the remaining liquids can be speeds up (chain reaction). Keep a careful eye on it, to disposed of in the sink. Clean the plastic materials with make sure you let the water out of the syringe before water and leave them to dry. Images courtesy of Gregor von Borstel

Collecting the gas

Mixing the two liquids via the three-way stopcock

Performing the oxyhydrogen test

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Discussion One possibility is to discuss lattice energy, using as an example from Other reactions commonly used in everyday life cold packs that rely on heater meals include the oxidisation an endothermic reaction triggered by of iron, the reaction of anhydrous cal- bending a metal plate. The following The source of cium chloride with water (see below) activity can then be used to introduce or, for cooling, the reaction of ammo- the activities: the notion of hydration energy and to nium nitrate fertiliser with water. demonstrate that the reaction by Lebensnaher Further experiments such as mak- which some salts dissolve is an ing your own heat and cold packs, or Chemie- exothermic reaction. determining the oxygen content in the The activity is relatively safe – the unterricht air with the aid of the iron oxidation most dangerous aspect is the possibil- reaction used in heat packs, are ity of breaking glass by not handling described on the LNCU websitew3. In 2003, four German it carefully. This activity can also form part of a chemistry teachers joined lesson in which the students develop forces to create a web por- Materials per group a script for a TV science programme tal to share their best teach- About 10 g anhydrous calcium to answer a viewer’s question on the · ing ideas: Lebens naher chloride function of heater meals. The English Chemie unterrichtw3 (LNCU, version of this worksheet is available Different sizes of beakers · chemistry lessons relevant on the Science in School websitew5, the Water · to everyday life). Their col- German one on the LNCU websitew3. Styrofoam / polystyrene (use rea- · lection has grown steadily, sonably large pieces as smaller A quick cup of hot coffee pieces are a nuisance when they and they offer a wide selec- In this activity, students heat coffee become charged and ‘stick’ every- tion of activities for all age using anhydrous calcium chloride where) ranges from primary to and water. The activity works well as Two laboratory thermometers upper-secondary school, part of a teaching unit on dissolving · Soluble coffee powder linking to major curricular salts in water, to introduce the ener- · getic aspects of this process. Students · Further items to awaken the stu- topics in chemistry, such as should already be familiar with ionic dents’ imagination, such as rubber the periodic table, titration, and covalent bonds. The activity bands, foil, batteries, etc. and air and water, plus works well with groups of three stu- biology and physics activi- dents aged 14 and over. ties for the youngest students. Their German-language Student worksheet materials are freely avail- 1. Using the materials provided, how can you achieve the highest able as downloadable possible temperature change when making coffee? PDFs and Word® docu- ments, with both instruc- You have 5 minutes to discuss your experimental approach in the group. Before you put your plan into action, check the safety (not the tions for teachers and feasibility) of it with your teacher. worksheets for students. In addition, the website offers You then have 10 minutes to perform the experiment. If you want to change your procedure part way through, check with your teacher. a range of videos on the activities and a list of more 2. Before you start, record the starting temperature of the air and the (German and English) coffee, and note the amount of coffee (in ml) you are making. websites with teaching 3. During the experiment, measure the air and coffee temperatures and ideas and relevant materi- note down the maximum temperature you achieve. als for the science class- Safety note: Wear safety goggles; do not drink the coffee.

BACKGROUND room.

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Science education projects

Potential approaches The required energy is drawn from You can also find a photo demon- the surroundings, so the solution stration of how the heater meals Two problems the students often cools down. In the coffee experiment, are prepared here: face are adding too little calcium chlo- in contrast, the hydration energy is www.mlaltd.co.uk/store ride to the water (the more they use, higher than the lattice energy, so the the more heat will be produced) and w5 – To download the English process as a whole is exothermic. forgetting to insulate their beakers. worksheets of the main Hydration and lattice energy are fixed A common solution to the task is to heater-meal and the heater-meal characteristics of an individual salt. improvise a small water bath by plac- science TV show activities, see: ing water and calcium chloride in a Further experiment www.scienceinschool.org/2011/ large beaker, and fixing styrofoam To follow this up, the students issue18/lncu#resources around the beaker with sticky tape. could try to achieve the lowest possi- Resources The coffee can then be heated in a ble temperature using anhydrous cal- For some microscale chemistry smaller beaker in the improvised cium chloride, sodium chloride and experiments using disposable water bath. ice. They may be surprised to find materials, from kindergarten to The best result within the context of that the addition of anhydrous calci- secondary-school level (in English the LNCU project (see box) was um chloride to ice (rather than water) and German), see: achieved by filling a small beaker does not increase the temperature. http://www.micrecol.de/ with water and placing it in a larger This is because the hydrogen bonds in beaker with a layer of styrofoam in- the ice crystals first have to be broken, If you find the idea of microscale between for insulation. The students which requires energy, so that the full chemistry experiments appealing, then placed the calcium chloride, to process is endothermic. you may also like: which they had added very little Kalogirou E, Nicas E (2010) water, in a small film canister. Web references Microscale chemistry: experiments Attaching a string to it and a stone for w1 – To order Crosse & Blackwell for schools. Science in School 16: weight, they let it hang into the water. heater meals online, see: 27-32. www.scienceinschool.org/ The temperature of 50 ml of coffee www.heatermeals.co.uk, 2010/issue16/microscale www.aapnespis.no or changed from 20 to 44 °C in less than If you enjoyed reading this article, www.dauerbrot.de a minute. why not take a look at the full list w2 - The ChemZ kits were developed of chemistry articles published in in close collaboration with the Science in School? See: Heating coffee with calcium chloride LNCU project, and offer a range of www.scienceinschool.org/ plastic materials normally used in chemistry medicine for use in school labs. For more information and to order materials, see: www.chemz.de w3 – The LNCU project is run by Dr Marlene Rau was born in German chemistry teachers Andy Germany and grew up in Spain. Bindl, Andreas Böhm, Gregor von After obtaining a PhD in develop- Borstel and Manfred Eusterholz. mental biology at the European For more information (in German) Molecular Biology Laboratory in

Image courtesy of Gregor von Borstel Image courtesy of Gregor von and to access all materials, see: Heidelberg, Germany, she studied www.lncu.de journalism and went into science Discussion w4 – Videos of the heater meals communication. Since 2008, she has Discuss the apparent contradiction (albeit an older version in which the been one of the editors of Science in between the behaviour of cold packs packs were in deep plates rather School. in previous experiments and the than today’s aluminium sachets) are experiment you have just performed – available on the Dauerbrot website in this case, the solution process is not (www.dauerbrot.de) or via the direct link: To learn how to use endothermic. In the cold packs, more this code, see page 1. http://tinyurl.com/6ewkvhw energy is required to destroy the salt’s molecular lattice (lattice energy) than as well as here is released when water molecules sur- www.aapnespis.no/Norsport1_0/ round the ions (hydration energy). show.htm

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Biomimetics: clingy as an octopus or slick as a lotus leaf? Astrid Wonisch, Margit Delefant and Marlene Rau present two activities developed by the Austrian project ‘Natur wissenschaft und Technik zum Angreifen’ to investigate how technology is inspired by nature.

n 2004, Alice Pietsch from the for other students. The exhibition Most of the activities from the exhi- University of Teacher Education Naturwissenschaft und Technik zum bition are suitable for the science classroom; here we present two activi- Styriaw1, Austria, was inspired by a Angreifen (‘Science and technology to I ties about biomimetics – the applica- simple but very visual demonstration touch’) took place in 2009 at the Haus tion of principles from nature to engi- at a science museum. A retired science der Wissenschaft (‘House of science’) in neering and technology. Velcro, which teacher was using bellows to pump Graz, Austria, where the students and mimicks the hooked seeds of bur- air into a pair of sheep’s lungs, rhyth- their teachers helped the visitors with dock, and boat hulls that mimic the mically inflating and deflating them. each activity. It was a huge success. The crowd around him was much larger than around many of the more high-tech exhibits – which is what prompted Alice to create an interactive science museum. In 2008, her dream came true. Over five months, Styrian students of all ages developed 50 different activities

to o h p k c o t S i / g n a h c f o

y s e t r u o c

m I

Octopus suction pads

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Science education projects

Biology 2. The article reminds you that force = area x pressure. Chemistry Here this is used to calculate the force of a suction

Physics pad. Can you think of some other contexts in which Image courtesy of midlander1231; image source: Flickr this equation could be used? Ages 5-19 3. It is very annoying (and noisy) when a shower tray Get stuck in! Or rather, give your students an opportu- attached by suction pads to a tiled shower wall falls nity to get stuck in with the activities described in the down. Explain what might make the suction pads article. ‘fail’ and cause the crash. The stickiness of tree frogs’ feet and of octopus tenta- 4. The article mentions that “dung beetles crawl out of cles prompts students to explore how this works using cowpats”. What might dung beetles be doing inside suction pads. Younger students will enjoy drawing cowpats and why might they be crawling out? This around their feet and the noises that the suction pads might take some research! make as they ‘slurp off’ when pulled. Older students 5. A scanning electron microscope is mentioned in the can appreciate the physics and explain what is happen- discussion of the second main activity. What is a ing using calculations. scanning electron microscope? How does it differ The stickiness of honey makes an appearance in the from a transmission electron microscope? second activity, along with ketchup, cinnamon and 6. The bumps on a lotus leaf are up to 20 micrometres curry powder – what student will not enjoy being let (μm) high. Express this height in a) nanometres (nm) loose with these ingredients? Investigating non-stick and b) millimetres (mm). lotus leaves and nasturtiums leads on to investigating novel self-cleaning liquids. This could lead to some 7. Explain, in your own words, what is meant by interesting debates, as well as practical work that · Hydrophobic ranges from simple tasks for young students (rolling · Hydrophilic water off leaves) to much more complex work for older · Surface tension students, working with sprays and using scanning elec- Pollutant tron micrographs to explain phenomena. · · Inorganic The first activity covers physics (pressure) and the sec- You could also get your students to carry out a risk ond activity, chemistry (surface interactions), both link- assessment for one or both of the activities. Some ing to biology with the idea that nature got there first – countries insist on these. Although it is the teacher’s which could be taken further and investigated by the role to provide a risk assessment, it is thought that if students. If different varieties of leaf are investigated, students are involved in creating their own risk assess- taxonomy can be introduced as well. ments, they are likely to be much safer as they will Here are some suggestions for questions you could ask have thought through the dangers themselves. Below your students after the activities: are some suggested responses, although any valid 1. Draw a diagram to show a suction pad before and responses or alternatives could be accepted. For some after it is pushed onto a surface. Annotate it to show activities, the likelihood of incidents may vary with the areas of high, low and equal pressure. age of the students. Risk assessment Danger Explanation of danger Likelihood (1 = very Severity (1 = very Prevention or reduction likely, 5 = very severe, 5 = minor unlikely) inconvenience) Fretsaw Cut skin 4 3 Train students how to use the saw safely and how to store it when not in use. Hold the pole in a vice if possible while cutting the grooves. Plants Some may be toxic 5 2 Only bring plants into school that are known to be safe Warn students, especially younger ones, not to eat the plants or put their fingers in their mouths

Some students may be 3 3 Ask students about any known allergies allergic to some plants or Check any medical records for younger parts of plants such as pollen students

REVIEW Sue Howarth, UK

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A tree frog Image courtesy of Nickodemo; image source: Flickr

thick skin of dolphins are common make kitchen machines more stable, 2. Tie a piece of string to each of the examples. The activities below inves- and on rubber mats in the shower or four suction pads. tigate suction pads and superhy- toy arrows. But why do they stick? 3. Tie the other ends of the string to drophobicity, both seen in nature. The If you look at a suction pad closely, the four grooves on the pole. Make activities were developed for younger you will notice that it is slightly sure the four lengths of string are secondary-school students (aged 10- curved. Could this curvature be exactly the same length. 15), but can easily be adapted for stu- important for the pad’s adhesive 4. Put the plastic board on the dents of virtually any age and are a power? And why do you need to wet ground, and use the permanent good opportunity for integrating suction pads before using them? Let’s marker pen to draw four circles for physics, chemistry and biology. investigate. the suction pads in a straight line. Depending on the level of detail you On either side of the line, draw a go into, the activities can each take Materials footprint (see image on page 55). anything from five minutes to over an 5. Press the suction pads onto the hour. · 4 suction pads (make sure you can attach a string to them) four circles. The full collection of activities A small fretsaw from the exhibition is available in · print in German from Birgit Muhr · A 50 cm pole, about 3-4 cm in ([email protected]) for €19 plus diameter (the students should be A fretsaw postage. able to wrap their fingers around it easily) Adhesion on flat surfaces: Four 50 cm pieces of strong string negative pressure · · A pair of scissors Household suction pads were A plastic board (about 1 x 1 m) inspired by the soles of tree frogs’ feet · A permanent marker pen and the tentacles of octopuses, whose · suction power was already known to the ancient Greeks. Procedure We use these pads on flat surfaces – 1. Using the fretsaw, make four equi- to attach hooks to bathroom tiles or distant grooves in the pole.

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Science education projects

Image courtesy of PHSt Archiv Water, saliva and other liquids work The setup for well to seal the pad, making it more the adhesion airtight and ensuring that air leaks activity. Alternatively, a back in less easily. Therefore, you single suction need even more strength to pull the pad and a suction pads off if you moisten them shorter piece of before applying them to a surface. wood can be used (see back Self-cleaning effects: of the image) hydrophobicity in nature Nature has some real cleanliness fanatics: dung beetles crawl out of cowpats looking spotless, you rarely find a dirty butterfly or dragonfly, and some plants are very successful at 6. What happens to the curvature of also a lower air pressure. The higher shedding filth. The Indian lotus, for the suction pads when they are pressure of the air outside the pad is example, grows in muddy waters, yet stuck to the plastic board? what keeps the pad stuck to the no dirt clings to its leaves; in fact, in Buddhism, the lotus is a symbol of 7. Stand on the footprints and try to board. purity. You can find this lotus effect pull the suction pads off the plastic You can calculate the force of a suc- closer to home, too: nasturtium leaves by pulling on the pole. tion pad as: 8. Repeat the experiment, wetting the F = AP, where F: force; A: area; Image courtesy of Professor Edith Stabentheiner, Karl-Franzens-Universität Graz suction pads before sticking them p: pressure. to the plastic board. What do you The area will be πr2 where r is the observe? radius of the pad. The pressure inside Discussion the cavity between pad and board is negligible when compared to atmos- When you press the suction pad pheric pressure, which is about onto the plastic board, you reduce the 100 000 Pa. So: pad’s curvature, thereby reducing the π 2 volume of the space between the pad F = r (100 000 Pa) and the board, and causing some of The time it takes for the pad to μ Image courtesy of tanakawho; image source: Flickr the air between the pad and the board come undone by itself (without 2 m to escape. When you stop applying applying additional force) will pressure, the elastic pad tends to depend on how porous and flat both A scanning electron microscopy image of a nasturtium leaf showing the com- resume its original, curved shape. The the rim of the pad and the underlying plex wax structures on the epidermis volume in the cavity between pad surface are, which determines how cells; these structures are responsible and board is increased again, but fast the air leaks back in and equili- for the superhydrophobicity there is less air in it, and therefore brates the pressure.

A lotus leaf showing off its hydrophobic properties

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The dung beetle remains spotless even when indulging in its favourite pastime Image courtesy of vendys / iStockphoto

and flowers look clean enough to eat, A Pasteur pipette and bulb, and of the same type of treatment on even without washing (rinse them · some small spoons different materials, or of different anyway, just in case). How do they types of treatment on the same manage without soap? · Ketchup, ground cinnamon and curry powder material. Humans have replicated this self- · Newspaper, kitchen roll and textiles 4. Use these and other nano-coated cleaning effect for many purposes, for materials (e.g. tiles) to repeat the Impregnation spray (e.g. for water- example, in self-cleaning plastics, roof · experiments, wetting and dirtying proofing suede), self-cleaning tiles, windowpanes, ceramics, wood them. What do you observe? and car varnishes, and façade paint. nano-based façade paint, nano- coating for wood or glass Safety note: Some students may be

You can also create dirt-repellent Image courtesy of midlander1231; image source: Flickr allergic to some plants or parts of clothes by impregnating them with a Optional: a nano-sealed roof tile · plants such as pollen. When using special spray. Procedure nano-coating, impregnation spray, How does it work? Let’s find out. 1. Wet the self-cleaning plants with etc., carefully read the instructions on Materials water, honey or glue and cover the package. They may require the them with ketchup, cinnamon or Parts of different plants with self- use of gloves or a well-ventilated · curry powder (to simulate dirt). cleaning properties, such as nastur- space. See also the general safety note What do you observe? tium leaves (Tropaelum majus), lotus on the Science in School website 2. Repeat the experiment with the leaves (Nelumbo nucifera), cabbage (www.scienceinschool.org/safety) hydrophilic leaves. What do you leaves (Brassica oleracea), and tulip and on page 65. observe? leaves (Tulipa spp.) 3. Now investigate the self-cleaning Discussion Parts of different plants with · properties of artificial materials. If you drop water or honey onto a hydrophilic leaves, such as leaves Spray textiles, kitchen roll and lotus leaf, it will roll off very quickly. of the common beech (Fagus sylvat- newspaper with different types of A close look under a scanning elec- ica) or the Southern magnolia nano-sealing treatments (e.g. tron microscope reveals why: large (Magnolia grandiflora) impregnating spray, paint or nano- numbers of tiny wax-covered bumps Water, runny honey and / or liquid · coating). Either compare the effect on the surface. These bumps are glue

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Science education projects

Images courtesy of Sarah Perfect / Syngenta

Scanning electron microscopy images (at magnifications of 300x, 2500x and 3000x) showing the wax structures on the surface of a rice leaf, similar to those on nasturtium or lotus leaves. The first image shows the waxy bumps amongst the stomata; the second image shows a stoma close up; the third image shows the papillate surface of the leaf and the fine detail of the wax structures

Θ about 10-20 μm high and 10-15 μm algae). On unwettable leaves such as The contact angle of a water droplet on a surface apart from one another. those of the lotus, it is not only the How does this structure help the adhesion of water to the surface that lotus leaf to remain clean? First, the is reduced – dirt is also simply surface of the lotus leaf is hydropho- washed away by the water. This is not bic (water-repellent). The hydropho- as obvious as it seems, though: there bicity of a surface can be quantified as are two different types of dirt parti- Public domain image; image source: Wikimedia Commons the contact angle between the surface cles – hydrophilic and hydrophobic ones. Hydrophilic particles such as and the drop of water: the higher the Droplets of fluid on a surface, demon- contact angle, the more hydrophobic silt are taken up in the water droplet strating different levels of hydrophobicity the surface (see image to the right). and cannot escape again. A track is Surfaces with a contact angle <90° are visible on the leaf where the drops called hydrophilic (‘water-loving’); have taken up the particles and those with a contact angle >90°, washed them away. hydrophobic. Some plants, which are But what about the hydrophobic known as superhydrophobic, achieve particles? You might expect them to Image courtesy of MesserWoland; image source: Wikimedia Commons contact angles of up to 160°, with only stick to the hydrophobic leaf surface, 2-3% of the drop’s surface in contact but in fact a drop of water will On a superhydrophobic surface, a drop with the surface of the leaf. However, remove these particles too. How does will be almost spherical and have a very low contact angle the lotus leaf is not only superhy- this happen? The particles only touch drophobic but also covered in the the outermost tips of the wax struc- aforementioned waxy bumps. These tures, and since this contact surface is reduce the contact surface of the tiny, so are the adhesive forces water droplet still further (imagine between particle and leaf. They are so the drop sitting on the points of the low that even the small adhesive bumps), with the result that the drop forces between the water-repellent Public domain image; image source: Wikimedia Commons barely touches the leaf (only 0.6% particle and water are stronger. So hair covering their leaves, butterfly surface contact) and runs off easily. unlike the hydrophilic particle, which wings have tiny ratchets that direct We have seen how the water flows is taken into the drop, the hydropho- raindrops away from the insect’s off, but how do the leaves get rid of bic particle sticks to the surface of the body no matter whether the wing is dirt particles? Plants are exposed to a drop. The end effect is the same, tilted up or down, and the cuticle of variety of pollutants, many of which though – it is washed off the plant. dung beetles has embossed geometri- are inorganic (dust or soot), although Superhydrophobicity is not limited cal textures that make it hydrophobic. others are of biological origin (e.g. to lotus plants: other plants have self- What is the advantage of these self- fungal spores, conidia, honeydew or cleaning properties thanks to mats of cleaning surfaces? For sedentary

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Close-up of a butterfly wing Image courtesy of William Thielicke; image source: Wikimedia Commons

plants, they are a way of protecting addition, if leaves are covered in dirt, Acknowledgements this reduces the surface available for themselves against micro-organisms, The two activities in this article photosynthesis. The self-cleaning such as fungi, bacteria or algae. Most were developed in the context of a wings of butterflies have the advan- plants fight these enemies chemically workshop led by Astrid Wonisch for tage of not retaining water and through a large range of secondary students of the Karl-Franzens- becoming heavy, which would pre- metabolites, but preventing them Universität Graz who were training to vent the insects from flying. from settling in the first place is become biology teachers, and includ- Humans have developed many potentially even more effective. In ed in the 2008 exhibition types of technology that emulate Naturwissenschaft und Technik zum these hydrophobic effects. Angreifen. Illustration of the Impregnation sprays, for example, Biology students Steffen Böhm and lotus effect cover the material with a wax-like coating that makes the materials Karin Edlinger worked together with hydrophobic. Some façade paints go students from the combined 7th and 8th even further, forming tiny bumps grade (aged 17-19) biomimetics class when they dry. These bumps are as at the secondary school BG / BRG water-repellent as the lotus’s wax Petersgasse, Graz, a secondary school structures with the result that the with a science and maths focus, and painted surface becomes superhy- the school’s biology teachers, Renate drophobic. Rovan and Ruth Unger, on ‘Adhesion

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Science education projects

Im a ge c o u r te s y o f S e c r e primary-school science activities. published in Science in School? See: t D i s c Science in School 16: 45-49. www.scienceinschool.org/teaching ; i m

a www.scienceinschool.org/2010/ g

s o issue16/lesa

; For a more in-depth overview of Dr Astrid Wonisch teaches plant

i bio-inspired design, comparing the physiology at Karl-Franzens-

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i achievements of nature and technol- Universität Graz, Austria. She is head

a C

o ogy, see: of the university’s didactics centre for

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n Vincent J (2007) Is traditional engi- s neering the right system with which and works with students who are to manipulate our world? Science in training to become biology teachers. Scanning electron micro- School 4: 56-60. www.scienc Margit Delefant is the deputy direc- graph of the minute scales einschool.org/2007/issue4 / tor of the regional didactics centre for that form the surface of a biology and environmental science in Peacock butterfly wing biomimetics Styria, Austria. She splits her time (magnification 50x) For more information on biomimicry, between teaching at the secondary see the Ask Nature website: school BG / BRG Fürstenfeld and at www.asknature.org the Karl-Franzens-Universität Graz, For further teaching activities on where she teaches didactics to future on flat surfaces: negative pressure’. superhydrophobicity and nano- biology teachers. waterproofing for different age Biology students Anna Dr Marlene Rau was born in ranges, see: Freudenschuss and Ingo Fuchs Germany and grew up in Spain. After worked together with students from a The EGFI website: obtaining a PhD in developmental th http://teachers.egfi-k12.org/ biology at the European Molecular

4 grade (aged 14-15) class at the sec- Images courtesy of Clifford Hart / Syngenta ondary school BG / BRG Fürstenfeld, nano-waterproofing Biology Laboratory in Heidelberg, Fürstenfeld, on ‘Self-cleaning effects: The Nanoyou website Germany, she studied journalism and hydrophobicity in nature’. (http://nanoyou.eu) or use the went into science communication. direct link: Since 2008, she has been one of the Web reference http://tinyurl.com/6d88zmd editors of Science in School. w1 – To learn more about the The NanoEd resource portal University of Teacher Education (www.nanoed.org) or use the direct To learn how to use Styria, see: www.phst.at link to the PDF: this code, see page 1. http://tinyurl.com/6dwxo2b Resources For more nanotechnology-related The German TV channel SWR has resources for the classroom, see: produced a series of short videos on Harrison T (2006) Review of Nano: suction pads in nature and technol- the Next Dimension and ogy, with accompanying teaching Nanotechnology. Science in School 1: materials (in German). See their 86. www.scienceinschool.org/2006/ education website Planet Schule issue1/nano (www.planet-schule.de) or use the Hayes E (2010) School experiments direct link: at the nanoscale. Science in School 17: http://tinyurl.com/6gey6tg 34-40. www.scienceinschool.org The following website offers a wealth /2010/issue17/nano of information on the lotus effect in Mallmann M (2008) English and German, including a Nanotechnology in school. Science small collection of videos: in School 10: 70-75. www.lotus-effekt.com www.scienceinschool.org/2008/ For primary-school teaching activities issue10/nanotechnology A droplet of water on the on hydrophobicity and the surface surface of a wheat leaf If you enjoyed reading this article, tension of water, see: why not take a look at our full Kaiser A, Rau M (2010) LeSa21: collection of teaching activities

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Image courtesy of Henrik5000 / iStockphoto Single molecules under the microscope

he idea of looking at single Binnig and his colleagues continued est details of the surface. When the molecules or atoms has fasci- to search for better solutions, and in tip, consisting of a single atom, comes Tnated scientists for over a hun- 1986, presented the atomic force close to the sample surface, it is dred years. This ambitious goal was microscope (AFM), which can be used deflected through forces between the first achieved in 1981 with the inven- to image both conducting and non- two: these can be mechanical contact tion of scanning tunnelling conducting materials. forces, van der Waals forces, capillary microscopy, for which Gerd Binnig The instrument works not unlike a forces, chemical bonding, electrostatic and Heinrich Rohrer at the IBM record player, in which a sharp needle forces, magnetic forces, Casimir

Image courtesy of lovestruck; image source: Flickr Research Laboratory in Rüschlikon, scans a vinyl record to reproduce forces, solvation forces or others, Switzerland, were awarded the Nobel sound (see image on page 62). The depending on the nature of the speci- Prize in Physics some time later, in AFM ‘feels’ the atoms, rather than men. 1986w1. This microscope has a severe ‘seeing’ them: the structure of a sur- Because this variety of forces can be limitation though: it works only on face is scanned with a very sharp measured with the AFM, it is very electrically conducting objects, so cone (typically of silicon or silicon versatile and has led to an explosion many interesting materials including nitride) at the end of a flexible can- in the number of scientists using the biomolecules could not be studied. tilever that can follow even the small- instrument – mostly but not only for material sciences and biology. In each case, the force causing the deflection is tiny and proportional to the tip’s distance from the surface. How can these tiny deflections be measured? The inventors used a clever trick: a laser spot is shone onto the top of the cantilever, from where it is reflected onto a position-sensitive light detector. The change in the laser spot’s position on the detector (see diagram on page 61, ΔH) due to a deflection of the cantilever (see diagram on page 61, Δh) is proportional

Boats suffering from biofouling

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Science topics

Would it not it be fascinating to observe and manipulate individual molecules? Patrick Theer and Marlene Rau from the European Molecular Biology Laboratory explain how, with an atomic force microscope, you can do just this. You could even build your own.

Position-sensitive ddetectoretector

to the distance between the detector Detector & ΔH and cantilever. With large enough dis- feedback tances between them, even tiny electronics Laser deflections can be measured, making it possible to study the structure of How the deflections of surfaces atom by atom. the AFM tip are magnified The applications of the AFM are and measured myriad. Let us take a brief tour of just a few of them. Δh Originally, AFM was developed to Sample surfacerface observe and analyse surface struc-

Image courtesy of Patrick Theer

Physics 2. What microscope was developed to overcome the Biology problems of scanning tunnelling microscopy? Medicine 3. Explain how AFM is like a vinyl record (please note Physiology that some students may not be familiar with vinyl Ages 14-19 records). 4. Explain the term biofouling. This article would be suitable for a wide range of sci- 5. Why is biofouling a problem? ence lessons – not only in physics but also when con- 6. Give examples of potential uses of AFM. sidering animal physiology or biomedical sciences, 7. What would you like to investigate if you had an for example. AFM? Students can research atomic force microscopy and The article could be used with groups of older stu- its uses further, as there is plenty of material on the dents or those most able to think creatively, perhaps Internet about the advantages and disadvantages of for an extended writing task in conjunction with the various microscopy techniques. They could also look film Honey I Shrunk the Kids (about a scientist work- up the group of scientists who invented the atomic ing on a top-secret machine that miniaturises objects force microscope (having won a Nobel Prize for a and – accidentally – people), to get the students to previous invention) and find out more about them think about looking at single molecules. What would and their work. they like to use AFM for? Would they use their images Potential comprehension questions include: as art or for scientific research? Would they want to use their knowledge to cure diseases or to see how 1. What was the limitation of scanning tunnelling beautiful science can be at this level? microscopy? REVIEW Jennie Hargreaves, UK

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Image courtesy of arbobo; image source: Flickr

tures in minute detail – not only is this interesting for research purposes, but it can have direct economic benefits: biofouling is the undesirable accumulation of micro-organisms, plants, algae and / or animals (such as barnacles, Cirripedia) on wet structures. On ship’s hulls, high levels of fouling can increase water resistance and thus substantially increase fuel consumption, but it is also an issue in The needle is poised membrane bioreactors, cooling water over a vinyl record, cycles of power stations and certain ready to begin scan- oil pipelines. Scientists use AFM to ning its surface to measure the degree of biofouling and produce sound thus compare the anti-biofouling activity of different substances, to Image courtesy of arbobo; image source: Flickr identify the ideal material (Finlay et al., 2010). Similarly, AFM has its uses in agri- tion can determine the behaviour of Another major field of application culture: pineapple plants often suffer the cells they will come into contact for AFM in medical biology is the from a fungal disease called fusario- with. Thus AFM can be used, for misfolding and aggregation of pro- sis. Scientists compared the surface example, to help design biomaterials teins such as α-synuclein, insulin, pri- structure of cells from pineapple culti- that are tolerated by the body and can ons, glucagon and β-amyloid. These vars that are resistant to this disease be used for medical implants such as phenomena have long been implicat- with those of susceptible cultivars, artificial hips (Al-Ahmad et al., 2010; ed in degenerative diseases such as and found that they have different Kolind et al., 2010; Padial-Molina et type II diabetes, Parkinson’s, spongi- mechanical properties. This can now al., 2011). form encephalopathy (‘mad cow dis- be used to select and improve resist- ease’), Huntington’s and Alzheimer’s. ant cultivars that have the required Here AFM has already provided mechanical properties (de Farias important information on the Viégas Aquije et al., 2010). nanoscale structure of the aggregates, Is surface structure relevant to and it is hoped that scientists will be human health, too? The answer is yes: able to use AFM to identify why the AFM studies are often used in den- protein misfolds in the first place, and tistry, for example to compare the how it encourages surrounding pro- effectiveness of different methods to teins to adopt the same misfolded remove plaque and stains; to measure structure (Lyubchenko et al., 2010; for the surface roughness of braces and an explanation of prion misfolding, see how this influences the effective- see Tatalovic, 2010). ness with which the teeth are pulled Further biological interactions that Image courtesy of Frantysek / iStockphoto into shape; or to quantify the erosion have been studied with AFM include of tooth enamel caused by acid in soft how human trophoblasts (cells form- drinks and test the efficacy of various ing the outer layer of a blastocyst toothpastes in repairing this damage which provide nutrients to the (Kimyai et al., 2011; Lee et al., 2010; embryo and develop into a large part Poggio et al., 2010). of the placenta) interact with epithe- Other medical applications include lial cells of the uterus – the basis of the development of new biomaterials successful embryo implantation (Thie in regenerative medicine: their surface et al., 1998). properties such as wettability, rough- It was only a small step from using ness, surface energy, surface charge, AFM for observations to using it to chemical functionalities and composi- manipulate atoms, molecules or other

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Science topics

The European Synchrotron Radiation Facility has developed an atomic force microscope especially for use on X-ray beamlines. One possible use is positioning nano-sized objects accurately in the X-ray beam. This is not a trivial task if both the object under study and the X-ray beam measure 100 nm or less across

AFM has a full set of tooth-related applications

Image courtesy of ESRF / Small Infinity

molecular or liquid ‘ink’. In chemistry tionsw2 for building your own instru- and the life sciences, such technology ment at school. It is a time-consuming is used to produce nanoscale sensors project, but he and his students man- or, by the deposition of metallic, semi- aged to create a feasibly low-cost conductor and metal oxide nanostruc- microscope. There is one important tures, functional nanocircuits or nan- catch though: you will need a vibra- odevices (Basnar & Willner, 2009). tion-free environment to set it up, This, combined with using the AFM such as a quiet cellar. If you can find tip to physically push nanometre- that, your enthusiasm and ingenuity sized particles to a desired position, are the only limitations. Image courtesy of webking / iStockphoto should pave the way for the miniatur- isation of electronic circuitry and References nanoscale structures. For example, other structures. Al-Ahmad A et al. (2010) Biofilm for- using the tip as nano-tweezers, pre- Despite its vast number of applica- mation and composition on differ- cise regions of the cell’s plasma mem- tions – these are just a small sample – ent implant materials in vivo. brane can be examined; individual the possibilities of AFM are not yet Journal of biomedical materials protein loops can be removed to exhausted. Future trends involve opti- research. Part B, Applied Biomaterials reveal the protein structure inside the mised tips and combinations with 95(1): 101-109. doi: molecule; and single molecules can be other techniques, for example to 10.1002/jbm.b.31688 stretched into novel conformations to simultaneously determine surface Ando T et al. (2008) High-speed AFM determine their elasticity. The next big structure and fluorescence or electri- and nano-visualization of biomolec- step will be using AFM for cal properties (Müller et al., 2006). ular processes. Pflügers Archiv: nanosurgery: introducing or extract- Speed is another issue: recently, an European journal of physiology 456(1): ing individual molecules from the AFM has been developed with which 211-225. doi: 456(1):211-25 cytoplasm of individual cells, to study biological processes such as chromo- cellular homeostasis or for subcellular some replication and segregation, Basnar B, Willner I (2009) Dip-pen- drug delivery (Lamontagne et al., phagocytosis and protein synthesis nanolithographic patterning of 2008; Müller et al., 2006). can be imaged in real time, up to 1000 metallic, semiconductor, and metal Modified AFM tips can also be used times faster than was previously pos- oxide nanostructures on surfaces. as drills or pens: nano-milling sible (Ando et al., 2008). Small 5(1): 28-44. doi: removes material in the form of long Are you now itching to come up 10.1002/smll.200800583 curled chips (Gozen & Ozdoganlar, with your own applications for AFM? de Farias Viégas Aquije GM et al. 2010), whereas dip-pen nanolithogra- Then you might want to try and fol- (2010) Cell wall alterations in the phy is the controlled delivery of low Philippe Jeanjacquot’s instruc- leaves of fusariosis-resistant and

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susceptible pineapple cultivars. Padial-Molina M et al. (2011) Role of and Martian dust grains Plant Cell Reports 29(10): 1109-1117. wettability and nanoroughness on (http://tinyurl.com/64z6xrb) doi: 10.1007/s00299-010-0894-9 interactions between osteoblast and If you enjoyed reading this article, Finlay JA et al. (2010) Barnacle settle- modified silicon surfaces. Acta bio- why not browse the full collection ment and the adhesion of protein materialia 7(2): 771-778. doi: of science topics published in and diatom microfouling to xerogel 10.1016/j.actbio.2010.08.024 Science in School? See: films with varying surface energy Poggio C et al. (2010) Impact of two www.scienceinschool.org/ and water wettability. Biofouling: toothpastes on repairing enamel sciencetopics The Journal of Bioadhesion and Biofilm erosion produced by a soft drink: Research 26(6): 657-666. doi: an AFM in vitro study. Journal of 10.1080/08927014.2010.506242 Dentistry 38(11): 868-874. doi: Gozen BA, Ozdoganlar OB (2010) A 10.1016/j.jdent.2010.07.010 Dr Patrick Theer is a physicist who rotating-tip-based mechanical Tatalovic M (2010) Deadly proteins: has spent most of his career develop- nano-manufacturing process: prions. Science in School 15: 50-54. ing microscopy techniques. After nanomilling. Nanoscale Research www.scienceinschool.org/2010/ studying medical physics in Berlin, Letters 5(9): 1403-1407. doi: issue15/prions Germany, in Toronto, Canada, and in Guildford, UK, he delved into the 10.1007/s11671-010-9653-7. The full Thie M et al. (1998) Interactions field of non-linear optics for a PhD at text article is freely available online. between trophoblast and uterine the University of Heidelberg, Kimyai S et al. (2011) Effect of three epithelium: monitoring of adhesive Germany, studying the imaging depth prophylaxis methods on surface forces. Human Reproduction 13(11): limit in two-photon microscopy – an roughness of giomer. Medicina Oral, 3211-3219. doi: 10.1093/hum- optical sectioning method that can Patología Oral y Cirugía Bucal 16(1): rep/13.11.3211. The full text article provide information from very deep e110-e114. doi: 10.4317/medo- is freely available online. within scattering tissues. For his post- ral.16.e110. The full text article is doctoral work, he moved on to the freely available online. Web references University of Washington in Seattle, w1 – To learn more about the discov- Kolind K et al. (2010) A combinatorial USA, studying voltage-sensitive dyes ery of the scanning tunnelling screening of human fibroblast using second harmonic generation microscope, which won Gerd responses on micro-structured sur- microscopy. Currently, he works as Binnig and Heinrich Rohrer the faces. Biomaterials 31(35): 9182-9191. a senior research assistant at the Nobel Prize in Physics in 1986, see: doi:10.1016/j.biomaterials.2010.08.048 European Molecular Biology http://nobelprize.org/nobel_prizes Lamontagne CA, Cuerrier CM, Laboratory in Heidelberg, developing /physics/laureates/1986 Grandbois M (2008) AFM as a tool a light-sheet-based fluorescence to probe and manipulate cellular w2 – To download the instructions for microscope for the study of embryon- processes. Pflügers Archiv: European building your own AFM at school, ic development. journal of physiology 456(1): 61-70. see: www.scienceinschool.org/ Dr Marlene Rau was born in doi: 10.1007/s00424-007-0414-0 2011/issue18/afm#resources Germany and grew up in Spain. After Lee GJ et al. (2010) A quantitative obtaining a PhD in developmental AFM analysis of nano-scale surface Resources biology at the European Molecular roughness in various orthodontic Swiss scientists have developed the Biology Laboratory, she studied jour- brackets. Micron 41(7): 775-782. doi: first AFM for planetary science, nalism and went into science commu- 10.1016/j.micron.2010.05.013 which forms part of NASA’s nication. Since 2008, she has been one Lyubchenko YL et al. (2010) Phoenix mission to Mars. For a of the editors of Science in School. Nanoimaging for protein misfold- video introduction, see the Azonano ing diseases. Wiley Interdisciplinary website (www.azonano.com) or To learn how to use this Reviews (WIREs). Nanomedicine and follow the direct link: code, see page 65. Nanobiotechnology 2(5): 526-543. http://tinyurl.com/6yguvb9 doi: 10.1002/wnan.102 ‘Universe today’ reports on the Müller DJ et al. (2006) Single-mole- instrument’s success in the mission. cule studies of membrane proteins. See their website Current Opinion in Structural Biology (www.universetoday.com) or follow 16(4): 489-495. doi: the direct links: snow on Mars 10.1016/j.sbi.2006.06.001 (http://tinyurl.com/6kp3rym)

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Teacher solidarity: a UK-Rwandan physics project Thanks to the determination of UK physics teacher David Richardson, increasing numbers of students in Rwandan schools are experiencing the delight of practical work. Vienna Leigh reports.

ention Rwanda and, even untary work at a secondary boarding Image courtesy of Zach Harden; image source: Wikimedia Commons now, people are most likely school, Apred Ndera, about 5 miles Mto think of its troubles; the from the capital Kigali, it was the Rwandan genocide, 1994’s mass education system that caught his killing of 800 000 people, is not some- attention. thing that can – or should – be easily “Students there are usually well- forgotten. Today, though, this east- motivated and have a strong desire to central African country is one of the do well, knowing that the way to Image courtesy of Green Lane; image source: Wikimedia Commons continent’s success stories, with an move on is to get a good education,” efficient government, notable eco- says David, who works at Clifton nomic growth and even a flourishing Collegew1, a boarding school in Bristol, tourism industry. But when, in 2004, UK. “Unfortunately, though, discus- physics teacher David Richardson vis- sion forms no part of the way they are ited a colleague who was doing vol- taught. Often they just copy the work

Clifton College in Bristol, UK

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Image courtesy of JonGorr / iStockphoto

Teacher profile

Rwanda is located in east-central Africa

from the board and try to understand results were more than he could have it later. Teachers aren’t valued in soci- hoped for. “Thanks only to word-of- ety and aren’t well paid, with many mouth publicity around the school, having more than one job to make the hall was packed with 300 stu- ends meet. They can also simply dents! It was great fun. When I have decide to leave one school to go and been back to visit, students tell me work elsewhere with no warning, that they still remember the physics meaning students are suddenly left they witnessed that day.” with no teacher.” This persuaded David to try to do During his visit, David taught the something to improve the practical senior 5 maths and physics class – work in Rwandan secondary schools. they put in. There was no shyness; 17-year olds – in their free periods. He looked at how practical work everyone wanted to learn, and they “Practical work isn’t common in could be fitted into the school syl- were all friendly and pleased to be Rwandan schools, particularly in labus. “I made a list and returned there. They were very excited to home with a mission to find a way to know what was in the first box!” The flag of Rwanda get the necessary equipment to stu- Even at mealtimes, the conversation ns dents in Rwanda,” he explains. often turned to physics. “It was inter- During the following year, he esting to hear about the politics of the approached the international depart- education system, and how teachers ment of the UK-based Institute of worked within this at their schools,” Physicsw2 (IOP) to see if they would says David. fund his idea. “My aim was to take David began by showing them cir- enough apparatus to allow five cuit apparatus. “They performed the schools to carry out demonstrations in experiments with care and precision, waves, dynamics, optics, electronics making careful notes, and were and modern physics,” he says. “I delighted that they would be able to planned to take four colleagues with take the apparatus away with them,” me in the summer holidays, to work he recalls. with ten local teachers, training them The teachers repeatedly came up to use the apparatus and giving them with further ideas about equipment the confidence to use it with their that they would like to be able to own classes.” show their students. “You really The IOP agreed to the funding, and appreciate how privileged we are in in August 2005, David, accompanied the UK when you see a teacher look- by IOP network coordinator David ing forward to the chance to use Grace, and a team from Gordano bulbs, batteries and ammeters with School, Portishead – head of physics their classes for the first time,” says Paul Crossthwaite, teacher Paul David. physics, mostly due to a lack of appa- Welch and 18-year-old Adam Aziz, The project did not stop there. ratus,” he says. “Any equipment they selected from among many student When David repeated the exercise in have is often incomplete or broken, or applicants – travelled back to Kigali. the summer of 2006, the IOP funding they simply don’t know how to use it. “Training the teachers was an amaz- allowed the number of schools receiv- They hadn’t even seen simple electric ing experience,” says David. “I was ing the apparatus to be increased circuits, and none could connect up a impressed with the hard work that from five to ten. In addition, battery pack to bulbs when I brought Students at Ada Senior High Image courtesy of Ernest Nanor these into the lesson.” School and Asi Daahey David was inspired to put together International Junior High a one-hour show covering the School in Ada, Ghana school’s physics syllabus. “I spent two weeks collecting together apparatus to demonstrate standing waves, oscillations in a pipe, Doppler and other wave effects,” he explains. The

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Images courtesy of Ernest Nanor

Students at Ada Senior High School and Asi Daahey International Junior High School in Ada, Ghana

Rwandan teachers who had been education. The IOP and Nature are Development programme. See: trained in 2005 carried out the train- working with the Kigali Institute of www.iop.org/about/international/ ing instead of their British counter- Educationw4 to ensure that the project development/africa parts. “I felt that this was important, is sustainable. A similar IOP project is so that the Rwandan teachers felt they being rolled out in Ethiopia, and there Resources were sharing what they had learned are plans to extend the initiative to If you enjoyed reading this article, with other colleagues from across the other African countries including why not take a look at our other country,” he says. “It was encourag- Ghana, Tanzania, Uganda and teacher profiles published in Science w5 ing to hear how they had been using Malawi . in School? See: the apparatus they had been given, “I hope and believe that this project www.scienceinschool.org/teachers and about the impact that this had provides a good model of how to had on their students.” start to introduce practical work into In addition, the IOP had also agreed secondary science education,” says to fund a workshop in which the David. “I’m looking forward to seeing Vienna Leigh studied linguistics at apparatus required could be assem- how the government responds to this the University of York, UK, and has a bled locally. Two technicians – former challenge and trust that, ultimately, it master’s degree in contemporary lit- students at Apred Ndera – were will be the students who see the bene- erature. As well as spending several trained to make the equipment. “Over fit: improved physics teaching.” years as a journalist in London, she 12 months, they produced 65 com- has worked in travel and reference plete sets of apparatus ready to be Web references publishing as a writer, editor and distributed to schools in Rwanda,” w1 – Find out more about Clifton designer. She then widened her scien- says David. “They displayed what College, Bristol, on their website: tific horizons at the European they produced at an education exhibi- www.cliftoncollegeuk.com Molecular Biology Laboratory in Image courtesy of RollingEarth / iStockphoto tion for Rwanda and Uganda, and Heidelberg, Germany, before moving w2 – The UK-based Institute of many people commented on the qual- to the Institute for Bioengineering of Physics is a scientific charity devot- ity, hardly believing that it was pro- Catalonia, Spain, as the head of com- ed to increasing the practice, under- duced locally.” It was at this point munications. standing and application of physics. that the science journal Naturew3 heard See: www.iop.org about the project. They are paying the salaries of the two technicians, initial- w3 – To find out more about the sci- ly for three years, and provide the ence journal Nature and associated money to buy enough components to activities, see: www.nature.com build 100 sets of apparatus each year. w4 – Learn more about the Kigali The final stage was to introduce a Institue of Education, a young pub- local project manager, so the project lic institution of higher learning in could be run from Rwanda. Since Rwanda, here: www.kie.ac.rw To learn how to use this code, see: then, David has met with representa- w5 –To help support physics educa- www.scienceinschool.org/help#QR tives from the Rwandan government tion in some of the poorest coun- to discuss the importance of practical tries in the world, you can donate demonstrations in secondary-school online to the IOP’s Physics for

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Image courtesy of domi-san; image source: Flickr

Scientist profile

Braille

To sea with a blind scientist Scientific research is not a career that most people believe to be suitable for the blind, but such beliefs are changing. Biologist Geerat Vermeij explains that, whether you are blind or not, science is competitive, tedious and hard – and he loves it.

Biology Questions relating to the article that could be asked in Image courtesy of YinYang / iStockphoto General science the classroom include: Ages 12-15 1. The author refers to biology as “that most visual of all the sciences”. Do you agree with this statement? This article could be used to introduce any scientific 2. Do you agree that science is that most powerful of subject, whether biology, geology, general sciences or all ways of knowing? something else. It could be used to discuss what 3. After reading the article, describe in your own working in science actually involves. Being a (blind or words what ‘being a scientist’ means. sighted) scientist involves so much exciting collabora- tive work: fieldwork, conferences in many different Alternatively, the question could be asked to the countries, writing articles, reviewing the work of other students before reading the article. After the stu- scientists, supervising PhD students and, of course, dents have read the article, compare and discuss if teaching. This article is perfect for a classroom discus- / how their views of being a scientist have changed. sion to ‘unmake’ the myth that working in science 4. Geerat Vermeij is a successful (blind) biologist. means being closed up all day alone in a laboratory. After reading the article, what more would you like This discussion could also be used to emphasise that to know about him and his work? Write three or scientists are normal people (whether blind or not) four questions and briefly justify each question. who build their careers on hard work and continuous Betina da Silva Lopes, Portugal study (see also the review of Leigh, 2010). REVIEW

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ow, a sceptic might ask, As a PhD student, Geerat Vermeij wondered could a blind person ever whether some molluscs had evolved elabo- rate shells such as this to ward off predators Hhope to be a scientist? After all, science is difficult even for many sighted people. How would I carry out experiments or read the huge scientific literature? Perhaps a blind person could be a theoretical physicist, but surely not a biologist. Why would the blind willingly choose biology, that most visual of all the sciences? Image courtesy of busypix / iStockphoto The answer is very simple: biology fascinates me. Someone is actually paying me to study shells – some of the most beautiful works of architecture in all of nature. What is more, I get to travel to exotic places, read the scientific literature in all its fantastic diversity, see my own papers and books published, and teach others about science, that most powerful of all ways of knowing. What more could one ask of a profession? Like many of my colleagues, I came to science early in life. Even as a small

Image courtesy of malmesjo; image source: Flickr boy growing up in the Netherlands, I picked up shells, pine cones and pret- asked me if I knew two of the speci- especially crabs and fishes, were ty stones. My parents, both of whom mens. Fortunately, the shells were responsible for this damage. I began are avid natural historians, encour- familiar to me and his misgivings to suspect that many of the elegant aged me; the fact that I was totally evaporated. After my PhD at Yale, I features of tropical shells – their knob- blind made no difference at all. At the moved to the University of Maryland by and spiny surfaces, their tight coil- age of ten, shortly after moving to the at College Park, becoming a professor ing, and the narrow shell opening USA, I became seriously interested in there in 1980. In 1988, I moved to the often partially occluded by knob-like shells and started my own collection. University of California, Davis, as a thickenings – could be adaptations to My parents and brother were enthusi- professor of geology. Along the way, I protect the snails inside from their astic; they read aloud, transcribed or married a fellow biologist and we had predators. dictated every book on natural histo- a daughter, Hermine, who is now 29. How do I do my research? I com- ry they could find. What do I actually do in my job that bine field, laboratory, museum and The reactions of my teachers at seemed so improbable to the sceptics? library work, visiting coral reefs, school ranged from polite acceptance Again the answer is simple. I do what mangrove swamps, deserts, rain to genuine enthusiasm when I told my sighted colleagues do: research, forests, research vessels, marine bio- them of my intentions to become a teaching and administration. logical stations, secret military instal- biologist. If they thought blindness My research centres on how ani- lations, great libraries and big-city and biology were incompatible, they mals and plants have evolved to cope museums all over the world. I collect kept it to themselves. with their biological enemies – preda- specimens in the field, work with liv- I moved on to study biology and tors, competitors and parasites – over ing animals in laboratory aquaria, geology at Princeton University, the course of the last six hundred mil- measure shells in museums and in my where I received strong support from lion years of Earth’s history. When I own very large research collection, nearly all of my professors, and then was still a PhD student, I noticed that and read voraciously. applied to do doctoral work at Yale many of the shells I found were bro- Wherever I go I am in the company University. The interviewer was ken, despite their considerable thick- of a sighted assistant or colleague. apprehensive; he took me down to ness and strength. It soon became There is nothing unusual about this; the university’s shell collection and clear that shell-breaking predators, every scientist I know has assistants.

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Scientist profile

At the library, as my reader reads to me, I transcribe extensive notes on the Perkins Brailler. My Braille scientific library now comprises more than 17 000 publications compiled in more than 300 thick Braille volumes. Like many of my colleagues, I spend a great deal of time writing. First, I prepare drafts on the Perkins Brailler, then type the manuscript on an ink typewriter. An assistant proof- reads and corrects the manuscript, which is then submitted to a journal. So far, I have published 205 peer- reviewed papers and books in this way. Teaching has always been inextrica- bly intertwined with research for me. Over the years I have taught a great variety of courses – animal diversity, evolutionary biology, ecology, marine ecology, malacology, the mathematics and physics of organic form, and a seminar on extinction. In the large introductory courses, teaching assistants take charge of the laboratory sections and help in grading papers. Again, there is nothing unusual in this: science professors at most universities depend heavily on teaching assistants (as a PhD student, I myself was lucky enough to receive full funding, which meant I did not need to be a teaching assistant). Like other research-oriented profes-

sors, I also train graduate students. Image courtesy of cobalt123; image source: Flickr Thus far, 15 students have received their PhDs under my direction. Of course, science isn’t all fun and police who mistook me for an opera- aged, be willing to take risks, get as games: it is competitive and hard tive trying to overthrow the govern- much basic science and mathematics work, full of tedious calculations, dis- ment of their African country. All education as you can take, and per- appointment when a cherished paper field scientists have similar experi- haps above all, display a reasoned is rejected, or quibbling about grades ences. The blind, no more than the self-confidence without carrying a with a frustratingly inept student. sighted, must act sensibly and with chip on your shoulder. You will need Nobody in science is exempt from appropriate caution. Along with inde- stamina, good grades, the support of this, but in the end the work is pendence comes the responsibility of influential scientists, and a willing- immensely rewarding. assuming risks. ness and ability to discover new facts In short, there is nothing about my What would I say to a blind person and new ideas. It is not enough to do job that makes it unsuitable for a who is contemplating a career in sci- well in courses; you must make new blind person. Of course, there are ence? Very simple. I would tell that observations, design and test inherent risks in the fieldwork; I have person exactly what I would tell a hypotheses, and interpret and present been stung by rays, struck down by sighted one: love your subject, be pre- the results in such a way that the stomach cramps and detained by pared to work hard, don’t be discour- work is both believable and interest-

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ing to others. Science is not for every- Resources If you enjoyed this article, you may like to browse the other scientist one, but I can think of no field that is Not all blind children attend a main- profiles in Science in School: more satisfying. stream school like Geerat Vermeij www.scienceinschool.org/scientists did; there are also schools especially Acknowledgement for blind and partially sighted stu- This article is reproduced with the dents. To learn more about one such permission of the NFB; a longer ver- school, and how science is taught sion of the article was published on there, see: the NFB website: Rau M (2010) Blind date in the sci- http://nfb.org/legacy/books/kernel1 ence classroom. Science in School 17. /kern0610.htm www.scienceinschool.org/2010/ issue17/wernerliese Reference To learn more about Geerat Vermeij’s To learn how to use this code, see: Leigh V (2010) Sowing the seeds of www.scienceinschool.org/help#QR research, see his latest book: science: Helke Hillebrand. Science in School 15. Vermeij GJ (2011) The Evolutionary www.scienceinschool.org/2010/ World: How Adaptation Explains issue15/helke Everything from Seashells to Civilization. New York, NY, USA: Thomas Dunne Books. ISBN: 9780312591083 Image courtesy of YinYang / iStockphoto

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Reviews

Bad science

To learn how to use this code, see: www.scienceinschool.org/help#QR By Ben Goldacre Reviewed by Eleanor Hayes, Editor-in-Chief of Science in School

en Goldacre, writer, broadcast- Over the course of his book, what is wonderful about science – sci- er and doctor, is on a crusade: a Goldacre examines: ence is powerful, it’s great fun, and scientific crusade – against · The misleading but accurate claims needn’t even be difficult. B I’m not a teacher, but I do have pseudoscience. of the cosmetics industry (read the Why should British teachers stop claims carefully: do they simply – some suggestions for how you could using the Brain Gym, which refers to and truthfully – state that one of use Bad Science in school. Give an itself as an ‘educational movement- the ingredients can make your skin individual chapter, or part of a chap- based model’ and is used in thou- look younger, or do they actually ter, to your students to read: they’ll sands of British schools? In Bad claim that the cream contains enjoy it (particularly the bit about Science, Ben Goldacre describes the enough of the ingredient to do why teachers shouldn’t use the Brain this?). Brain Gym as “a vast empire of pseu- Gym in lessons) and it will encourage doscience” that tells children “that if · How we test whether a treatment them to question the world around they wiggle their head up and down works (why is the ‘evidence’ for them. it will increase the blood flow to the homeopathy flawed? How can you Get your students to practice what design a fair test of a treatment?). frontal lobes, thus improving concen- Ben Goldacre preaches: exposing tration; … that there is no water in · Some fascinating research on the pseudoscience for what it really is. processed food; and that holding placebo effect, how the results can Why not ask the class to collect pseu- water on their tongue will hydrate the explain some of the claims of pseu- doscientific claims (e.g. from newspa- brain directly through the roof of the doscience, and how the placebo pers, the Internet, adverts) and dis- effect could be used in convention- mouth”. In a sense, he acknowledges, cuss them in class? Perhaps you could al medicine. the Brain Gym works: it encourages have regular ‘pseudoscience busting’ My only criticisms are minor. The regular breaks in lessons, light exer- lessons: why is a particular claim mis- book would benefit from a more care- cise and drinking plenty of water. All leading? Could there be any truth in ful editor, to correct some grammati- good – and effective – activities. it? If so, what could the real explana- cal errors, improve some clumsy sen- So what’s the problem? According tion be, and how could you set up an tences and – more importantly – to Goldacre, this “transparent, shame- experiment to test it? Perhaps your remove some leaps in logic or missing students could even carry out the ful and embarrassing nonsense” information. Also, I suspect that many experiment. poses two problems, which apply to readers will find statements like “you Finally, to read Ben Goldacre’s all pseudoscience. First, you can blind may disagree, and you now have the weekly newspaper column, visit the people with scientific-sounding lan- tools to do so meaningfully” rather Bad Science websitew1. guage and get them to do something patronising. intrinsically sensible, but is it ethical Notwithstanding, Bad Science is a Details to lie to them to achieve this? Second, wonderful book and appropriate for a Publisher: Fourth Estate by hiding common sense in scientific- wide audience. Read it – please! Enjoy Publication year: 2008 sounding hocus pocus, you create a it, share it with your friends and col- ISBN: 9780007240197 veil of mystery around science, pre- leagues and above all, with your stu- venting people from thinking for dents. It’s simply written, funny and Web reference themselves about seemingly scientific utterly compelling; I nearly missed a w1 – Bad science: claims or using the scientific knowl- train connection because I was so www.badscience.net edge they have. absorbed in it. This book reminds us

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Instructables website

Reviewed by Sue Howarth, UK and Marlene Rau, Germany

ww.instructables.com is a Instructables are step-by-step More complicated projects include the w8 website that shows you descriptions of things that people breath-powered USB charger , build- w9 how to make all sorts of have made, along with information ing a macro particle accelerator that W about how they made them. As the propels a conductive ping pong ball, weird and wonderful things, from w10 apple coasters to a z-bend hyper- site says, they are “educational, inspi- or creating a lighted star map . Or hornet. rational, and often replicable”, and so you may trick your students with the w11 With this exciting website, you can they could be useful for enhancing fake portable gravitation shield – access most of the information with- and enriching science, technology, very useful for teaching magnetics. out registration. For this review, we engineering and maths subjects, in Whereas many of the instructables registered for free membership (you and out of the classroom. The con- from the ‘Technology’ and ‘Solar’ sec- don’t have to) and were sent a tents are divided into a number of tions are most appropriate for use in welcome message, followed by a sections, such as ‘Health’, ‘Outside’, the physics classroom, there are many personalised email from the ‘Solar’ and ‘Technology’. The key- interesting ideas for the other sci- ‘Instructables Robot’, which tells word-guided navigation leading to ences, too: you could make lumines- w12 you that there are “tons of awesome specific collections of instructables cent silicone paint , grow silver w13 things to see on Instructables”, and and information is not always intu- crystals or build a ballistic soap w14 offers a choice of browsing or a itive, but it can be helpful. bubble machine in the chemistry “guided tour”. Some of the instructables are clearly classroom. In Earth sciences, building w15 The guided tour really helped; we rather specialised, such as the dachs- a tsunami model with gutter w1 did not really understand what the hund wheelchair , made to help an segments could be fun; and in site was about until we worked injured dog exercise during recovery, biology, you could grow oyster w16 through it. The ‘home’ page does not or fun-based, such as making a mer- mushrooms in a coffee cup , have w2 tell you enough, but the tour certainly maid tail for swimming . Many other the students build muscular anatomy w17 does. Through this, we learned that ideas, however, are very educational, models with Halloween skeletons , w18, w19 Instructables is a web-based “docu- and certainly many look both exciting bake or sew a cell model , or, if mentation platform” where “passion- and feasible for students to try them- you want to get seriously involved, ate people share what they do and selves, with suitable help as appropri- build your own thermocycler for w20 how they do it, as well as learn from, ate. This could be as a project or per- PCR . and collaborate with, others”. This haps as extension and / or extracur- The numbered steps for all the was still a little vague, and had we ricular activities, or even in cross-cur- instructables, or projects, ought to not been prompted by pictures of all ricular groups. The longer you make following the instructions easi- sorts of gadgets, we might have won- browse the site, the more you find. It er, and the accompanying pictures dered what we had wandered into. A seems to be a very active site, with look as though they should help a link to the “awesome people” who new material being constantly added. great deal. Some of the materials, e.g. make Instructables happen, reassur- For the physics classroom, there is “ultra-concentrated Dawn dish deter- ingly shows some fairly normal peo- a large variety of gadgets to be built gent (blue)”, might be hard to come ple, and, in the terminology of the as teaching activities, such as a by outside the USA, but the great w3 site, the “seeds of Instructables germi- simple steam engine or a Stirling thing about this site is that you can w4 nated” at the Massachusetts Institute engine built from a crisp package , ask about alternatives and are likely of Technology Media Lab in Boston, a Savonius wind turbine built from to get a response from either the proj- w5 USA, with the site developing as a cardboard , a fifteen-minute ect maker or others who contribute to w6 place for sharing projects and helping self-propelled hovercraft or a solar- feedback and discussions on the site. w7 others. powered LED-lighted sun jar . Suggestions for modifying projects

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Reviews

are common, giving a strong sense of Web references user involvement. Below are the links to the individual instructables mentioned in the article. Obviously, teachers thinking of The URLs are fairly self-explanatory: using any of the ideas need to try w1 – www.instructables.com/id/Dachshund-wheelchair them first and make sure that all the necessary materials are to hand. It is w2 – www.instructables.com/id/How-to-Make-A-Mermaid-Tail-for useful that approximate costs are -Swimming given. Importantly to note is that the w3 – www.instructables.com/id/A-Simple-Steam-Engine-Anyone-Can-Build extent of the safety advice provided w4 – www.instructables.com/id/The-amazing-pringles-tube-Stirling-engine for each project is variable, so a thor- w5 – www.instructables.com/id/Cardboard-Savonius-turbine ough risk assessment would be neces- w6 – www.instructables.com/id/Fifteen-Minute%2c-Self-propelled-hovercraft sary before letting students start. w7 – www.instructables.com/id/Home-made-Sun-Jar If all goes well, and students want a further challenge, there is scope to w8 – www.instructables.com/id/Breath-powered-USB-charger design their own instructable, and a w9 – www.instructables.com/id/How-to-make-a-macro-particle-accelerator guidew21 is provided to help with this w10 – www.instructables.com/id/Star-Map and to show how to upload it onto w11 – www.instructables.com/id/A-small-portable-gravitation-shield the site. w12 – www.instructables.com/id/Making-Ooglo-Luminescent-Silicone-Paint In addition to step-by-step instructions, the website offers photos and w13 – www.instructables.com/id/Grow-Silver-Crystals-by-Electrochemistry videos of the gadgets, informative w14 – www.instructables.com/id/Make-a-Ballistic-Bubbles-Machine articles on miscellaneous topics, con- w15 –www.instructables.com/id/Tsunami-Model tests amongst the users for uploading w16 – www.instructables.com/id/Gourmet-mushrooms-in-an-old-coffee-cup the best instructable on a given topic w17 – www.instructables.com/id/Muscle-anatomy-with-Sugru-and-a – such as the ‘Belt re-use challenge’ or -Halloween-skeleton the ‘Homemade soup contest’, and a w18 – www.instructables.com/id/Plant-Cell-Cake very active discussion forum, including a question-and-answer section. w19 – www.instructables.com/id/Plush-Cell-Model Note: There is an option of signing w20 – www.instructables.com/id/Coffee-Cup-PCR-Thermocycler-costing up and paying for ‘pro’ membership, -under-350 for USD 1.95 / month, billed annually w21 – For instructions on how to create your own instructables, see: or USD 39.95 for two years as a one- www.instructables.com/id/How-to-make-a-great-Instructable time payment. A membership com- parison list points out that signing up as a paid member would let you To learn how to use this code, see: download PDFs, see instructions on a www.scienceinschool.org/help#QR single page, view less advertising, and generally help to support the site. Members also receive the newsletter and gain access to past newsletter archives.

www.scienceinschool.org Science in School Issue 18 : Spring 2011 sis_18_RZ_.qxq:Layout 1 15.03.2011 18:19 Uhr Seite 76

Relativity: A Very Short Introduction

By Russell Stannard Reviewed by Michalis Hadjimarcou, Cyprus

elativity is, admittedly, a diffi- worm holes, supernovas, the expand- Details ing Universe, dark energy and dark cult subject to understand, Publisher: Oxford University Press matter are but a few of such issues even to science-oriented peo- Publication year: 2008 R Stannard has elaborated on and ple. In Relativity: A Very Short ISBN: 9780199236220 Introduction, Russell Stannard has enables the reader to distinguish made an effort to explain relativity between science and imagination. and its implications for the laws that In school, there are a number of ways govern the Universe in a way that can in which this book can be useful, be understood by those with at least especially in an advanced physics or some basic knowledge of physics. astronomy class. Considering that the The book is rich in scientific terminol- theory of relativity is taught in sec- ogy, so a good knowledge of English ondary schools across the world, is essential to understand it. Stannard teachers can use the book to draw has also included a wealth of dia- basic information on the theory itself, grams and mathematical equations. but more importantly, to inform To learn how to use this code, see: These can make the book more diffi- themselves and their students on the www.scienceinschool.org/help#QR cult to understand if the reader is not latest theories regarding the nature adequately trained in dealing with and the peculiarities of the Universe. such information. But, there is an Students might find it very difficult to alternative solution: ignore most of read and understand the entire book, the diagrams and formulas and con- but if they concentrate on specific sec- centrate only on the basic ideas pre- tions of the book, with a little help sented. Such casual reading will allow from their physics teacher, they will the reader to filter out all the explana- be able to benefit greatly from it. tory details and keep the basic Along those lines, the teacher could description of what relativity is all assign projects to his students that about. Of course, if one is determined would require more careful study of to capture the full extent of relativity, specific sections of the book. this book provides an excellent opportunity for achieving this. The book is also available in a German translation. Regardless of the background and scope of the reader, he / she will be rewarded in the last chapters of the book with information on exciting subjects, the type favoured by science fiction. The Big Bang, black holes,

Science in School Issue 18 : Spring 2011 www.scienceinschool.org How many schools Spring 2011 Issue 18 and teachers do you reach – worldwide? In this issue: Biomimetics: clingy as an octopus or slick as a lotus leaf?

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