On Wildlife Trafficking

Issue 24 Issue 2012 Autumn

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a ov Published by EIROforum: Published by ts w ts ith tar learn about innovative education approaches collaborate with key businesses to inform pupils about careers access and use a repository of best industry–school education activities s you Inn • • • inGenious is the largest European platform dedicated to helping science teachers communicate the value and career engineering and maths studies. potential of science, technology, Industry and school collaboration is at the heart of inGenious. Enter our Community to: Join inGenious at: http://ingenious-science.eu/web/teachers/home InGenious is supported by the European Union’s Framework Programme for Research and Development (FP7) – project ECB: European Coordinating Body in Maths, Science and Technology InGenious is supported by the European Union’s Framework Programme for Research and Development (FP7) – project ECB: does not represent the opinion of the European Union and the (Grant agreement Nº 266622). The content of this advertisement is the sole responsibility of the Consortium Members and it European Union is not responsible or liable for any use that might be made of information contained herein. Collaborate with industry Join the community www.ingenious-science.eu inGeniousA4advert.indd 1 Editorial About Science in School The European journal for science teachers Science in School is the only teaching journal to cover all sciences and target the whole of Europe and beyond. Contents include cutting- s I write this, the children in my village have edge science, teaching materials and much been back at school for two weeks. The school more. just down the road, however, doesn’t start Brought to you by Europe’s top scientific A research institutes again for another two weeks. If school holidays – and indeed school types, curricula and teacher training – Science in School is published and funded by EIROforum (www.eiroforum.org), a partnership differ so much within Germany, how much variation between eight of Europe’s largest intergovern- must there be across Europe? mental scientific research organisations. Inspiring science teachers worldwide Nonetheless, some of the challenges for science The Science in School website offers articles teachers are the same wherever you are in the world. How to inspire your in 30+ languages and is read worldwide. The students? How to share the fascination of science? And how to keep your- free quarterly journal is printed in English and self up to date with the latest scientific developments? distributed across Europe.

Supporting you in these challenges is what Science in School is all about. Advertising: tailored to your needs In this issue, for example, we have suggestions to motivate even the least Choose between advertising in our print journals or on our website. For maximum enthusiastic students. They could synthesise indigo – treasured by the Egyp- impact, reach our entire readership with an tian pharaohs and still used to dye jeans (page 40) – or investigate how we advertorial (online and in print). Online and in trick our brains into perceiving 2D pictures as 3D (page 29). Drinking wine print, we have a total of 100 000 readers per at school is probably not a good idea, but producing and analysing it intro- quarter. duces a wide range of chemistry topics (page 47). And if you teach younger · The majority of our readers are secondary- school science teachers. children, they can discover for themselves how materials change when we · Our readership also includes many primary- heat them (page 23). school teachers, teacher trainers, head teachers and others involved in science Whether you are looking for cutting-edge science for your lessons or simply education. feeding your own thirst for knowledge, Science in School has plenty to offer. · The journal reaches significant numbers Did you know, for example, that genetic analysis is used to combat the il- of key decision-makers: at the European legal wildlife trade in Brazil (page 6)? Or are you puzzled by the behaviour Commission, the European Parliament and in European national ministries. of an autistic student (page 17)? Next time you teach the electromagnetic For more information, see spectrum, you could show how radiation is used to monitor what goes on www.scienceinschool.org/advertising or in a fusion reactor (page 12) and to investigate the mysteries of the distant contact [email protected] Universe (page 53). And if you think you’ve already mastered all there is to know about crystal structure, maybe it’s time to think again (page 59)? Subscribing Register free online to: Colleagues can be a source of inspiration – but they don’t have to be the · Subscribe to the e-newsletter teachers down the corridor. Earlier this year, a group of teachers from Aus- · Request a free print subscription tria, Germany and Italy travelled to Spain to learn from a truly inspirational (limited availability) · Post your comments. primary school (online article). Clearly, that’s not possible for every teacher, which is why we regularly introduce you to inspiring European teachers: in How can I get involved? this issue, find out how a Polish teacher rose to the challenge of teaching Science in School relies on the involvement of teachers, scientists and other experts in science physics to disabled children (online article). education. Finally, don’t forget that many of our articles are available online in other · Submit articles or reviews · Join the referee panel European languages, thanks to volunteer translators across Europe. To view · Translate articles for publication online all the articles in your language, just click on the relevant flag on our web- · Tell your colleagues about Science in School site. And if you’d like to translate our articles into your native language, · Make a donation to support the journal. See www.scienceinschool.org or contact us. we’d love to hear from you. Contact us Eleanor Hayes Dr Eleanor Hayes / Dr Marlene Rau Science in School Editor-in-Chief of Science in School European Molecular Biology Laboratory [email protected] To learn how to Meyerhofstrasse 1 www.scienceinschool.org use this code, see 69117 Heidelberg page 65. Germany i I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Contents

Image courtesy of SOS Fauna Editorial i Welcome to the twenty-fourth issue of Science in School News from the EIROs 2 Bigger, faster, hotter Feature article 06 6 Cracking down on wildlife trafficking Images courtesy of Norma Desmond (Flickr) Cutting-edge science and paulaphoto / iStockphoto 12 Seeing the light: monitoring fusion experiments 17 Behind the autistic spectrum Teaching activities 23 The effect of heat: simple experiments with solids, liquids and gases 29 Seeing is believing: 3D illusions 17 Advertorial 36 In a class of their own: lessons in energy and education Image courtesy of Stock photo for free.com from European schools Science education projects 40 Indigo: recreating Pharaoh’s dye 47 Analysing wine at school Science topics 53 More than meets the eye: the exotic, high-energy Universe 29 59 The new definition of crystals – or how to win a Nobel Prize

Image courtesy of def110; image source: Flickr Additional online material Event Learning through investigation: Science on Stage visit to El Roure Gros primary school Teacher profile 47 Making physics flourish in Poland: Maria Dobkowska

Image courtesy of Tiflex 2; image source: Flickr Reviews The Eduspace website The Periodic Table of Videos website

Forthcoming events for schools: www.scienceinschool.org/events To read the whole issue, see: www.scienceinschool.org/2012/issue24

59 To learn how to use this code, see page 65. www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 1 Image courtesy of EFDA-JET

Bigger, faster, hotter Science in School is published by EIROforum, a collaboration between eight of Europe’s largest inter-governmental scientific research organisations. This article reviews some of the latest news from the EIROforum members (EIROs).

EFDA-JET: CERN: Refurbished JET – clean,

The masters of the Internet – Image courtesy of EFDA-JET hot and safe

and you can be one, too! An infrared image of the inside of the JET vessel shows hot spots (reddish) Although a lot of people know that the World Wide Web during a plasma disruption was invented at CERN, not many know that the organisation has also played a central role in developing the Internet in Fusion energy researchers at the Joint European Torus Europe. In 1988, CERN convened the historic meeting that led (JET) continue to reap rewards from the 2009-2011 upgrade. to the creation of the RIPE (Réseaux IP Européens), which still The new metallic walls in the reactor have led to much allocates IP addresses in Europe. In the early 1990s, CERN was cleaner plasma, without the undesirable radiation caused the largest Internet hub in Europe, managing more than 80 % by contaminants from the previous carbon wall. In addition, of the international bandwidth available on the continent. It the new heating systems can deliver 40 % more power to the was also one of the founding members of the Internet Society, plasma in 50 % longer pulses. a global organisation dedicated to ensuring that the Internet Nonetheless, turbulent events known as disruptions – in stays open, transparent and defined by its users. The society which the energy of the plasma escapes its magnetic cage in celebrated its first 20 years at a conference held in Geneva, one spot and hits the wall – still occur occasionally. Because Switzerland, from 22 to 24 April 2012, with CERN as a special the new wall has a lower melting point than the previous guest. one and higher plasma temperatures are now being used, a To mark the occasion, the Internet Society established a website protection system had to be developed before the full heat- where people can share their ideas and wishes on how the Inter- ing power could be applied. This will mitigate disruptions net should evolve: http://wishingtree.internetsociety.org because the associated heat levels and magnetic forces can be Get involved, and make the Internet your place, too! extremely high. To find out more about the Internet Society, see: www.internetsociety.org Recent tests have shown that the protection system suc- Based in Geneva, Switzerland, CERN is the world’s largest particle cessfully detects disruptions and then quickly puffs argon gas physics laboratory. To learn more, see: www.cern.ch into the vessel. The argon rapidly ‘contaminates’ the plasma, For a list of CERN-related articles in Science in School, radiating energy in all directions, thereby diffusing the hot see: www.scienceinschool.org/cern spot. The JET team now has the confidence to turn the new system up to record power levels in the coming months. To find out how hot spots and other potential problems are monitored within the JET reactor, see: Dooley P (2012) Seeing the light: monitoring fusion experiments. Science in School 24: 12-16. www.scienceinschool. CERN’s director general (third org/2012/issue24/fusion from right) participating in a Situated in Culham, UK, JET is Europe’s fusion device. Scientific round-table discussion at the exploitation of JET is undertaken through the European Fusion INET 2012 forum in Geneva

Image courtesy of CERN Development Agreement (EFDA). To learn more, see: www.

efda.org For a list of EFDA-JET-related articles in Science in School, see: www.scienceinschool.org/efdajet

2 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Image courtesy of Nik Szymanek / FT LCOGT

News from the EIROs

Composite image of Faulkes Telescope North and the Milky Way Biology

EMBL: Filming life in the fast lane

Scientists at the European Molecular Biology Laboratory (EMBL) have filmed the development of a fruit fly embryo from when it is about 2.5 hours old until it crawls away from Chemistry the microscope as a larva, 20 hours later. In the video, you can watch as cells on the embryo’s belly dive in to form what’s known as the ventral furrow. Other cells can then be seen moving around the embryo’s rear end to its back, in a process called convergent extension. Later, when an opening appears in the embryo’s back, you can see the surrounding cells close ESA: the gap in a process known as dorsal closure. Join the asteroid hunt

To obtain the video, the scientists developed a new micro- Physics scope called multi-view SPIM, which enables them to image The European Space Agency (ESA) has recently joined rapid biological processes in thick samples in unprecedented forces with the UK’s Faulkes Telescope Project to allow stu- detail. They can obtain a high-quality 3D image of a fruit dents to support the Agency’s Space Situational Awareness fly embryo in just a few seconds. Using such fast imaging, (SSA) programme. This programme keeps watch over space the movements of every nucleus in the early embryo can be hazards, including disruptive space weather, debris objects recorded. in Earth orbit and asteroids that pass close enough to Earth In the future, the scientists would like to use their new to cause concern. microscope to investigate how organs and tissues form, not Any attempt to survey and catalogue hazardous asteroids General science only in the fruit fly but also in other organisms. faces a number of difficulties. They are often jet black or at To watch the video and for more information about the micro- least very dark, can approach rather too close before anyone scope, see the press release on the EMBL website (www.embl. sees them, and are often spotted only once and then disap- org) or use the direct link: http://tinyurl.com/muvispim pear before the discovery can be confirmed. To watch other EMBL videos, see the EMBL Youtube channel: So ESA is turning to amateur astronomers to ‘crowd- www.youtube.com/user/emblmedia source’ observations as part of Europe’s contribution to The original publication is: the global asteroid hunt. These efforts will greatly enhance Krzic U et al. (2012) Multi-view selective-plane illumination mi- asteroid-spotting for the SSA programme, enabling detec- croscope for rapid 3D imaging of developmental processes with tion of fainter objects and tracking from a global telescope sub-cellular resolution. Nature Methods 9: 730-733. doi: 10.1038/ network. NMETH.2064 The Faulkes Telescope Project offers free access to robotic For an earlier Science in School article about how embryo develop- telescopes and a fully supported education programme to ment is observed at EMBL, see: encourage teachers and students to engage in research-based Furtado S (2010) Watching it grow: developing a digital embryo. science education. Supporting ESA’s SSA programme is just Science in School 15: 18-22. www.scienceinschool.org/2010/ one of the many possible astronomy projects that schools can issue15/zebrafish engage in. For a list of EMBL-related articles in Science in School, see: Go to the Faulkes Telescopes website to join the hunt: www.scienceinschool.org/embl www.faulkes-telescope.com Foreground: early Drosophila embryo with the cell nuclei To learn more about using the Faulkes Telescopes at school, see: marked. Background: an unrolled image of a Drosophila Dodds R (2007) The Faulkes Telescopes: real-time, remote- embryo with the cell membranes marked (the alternating control astronomy for schools. Science in School 4: 42-45. green / magenta colour represents different views from the www.scienceinschool.org/2007/issue4/faulkestelescope microscope) For another asteroid-hunt teaching activity, see:

Image courtesy of Uroš Krži č / EMBL Heidelberg Newsam A, Leigh C (2011) Hunting for asteroids. Science in School 20: 30-35. www.scienceinschool.org/2011/issue20/ asteroids ESA is Europe’s gateway to space, with its headquarters in Paris, France. For more information, see: www.esa.int For a list of ESA-related articles in Science in School, see: www. scienceinschool.org/esa

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 3 EIROforum EIROforum combines the resources, facilities and expertise of its member organisations to support European science in reaching its full potential. To learn more, see: www.eiroforum.org ESRF: For a list of EIROforum-related articles in Science in School, see: When insects first www.scienceinschool.org/eiroforum became pollinators To browse the other EIRO news articles, see: www.scienceinschool.org/eironews Image courtesy of ESRF

ESO: Synchrotron tomography image of a specimen of Gymnos- pollisthrips minor covered with pollen grains (yellow). These World’s biggest eye on the sky grains are minuscule and exhibit adherent features so that insects can transport them The European Southern Observatory (ESO) is to build the largest optical / infrared telescope in the world. The ESO Insect pollination of plants is a relatively recent event council approved the European Extremely Large Telescope in Earth’s history – water and wind did the job before the (E-ELT) programme at its meeting in Summer 2012, pending little creepy-crawlies arrived. But once they did, a mutual confirmation of four ad referendum votes. The E-ELT will be evolutionary success story started: today, by far the majority a 39.3 m segmented-mirror telescope sited on Cerro Arma- of flowering plant species are pollinated by insects, which zones in northern Chile, close to ESO’s Paranal Observatory. transport the pollen from male to female plant parts. But Operations are planned to start early in the next decade, and how did it all begin? the E-ELT will tackle some of the biggest scientific challenges Flowering plants are a comparatively recent group, evolv- of our time. “The E-ELT will keep ESO in a leading position ing from gymnosperms. These ‘naked seed’ plants have cones instead of flowers, and include today’s conifers and for decades to come, and lead to an extraordinary harvest Ginkgo. Although most gymnosperms used wind pollination, of exciting science,” said ESO council president, Xavier some already used insects as pollinators – well before the Barcons. evolution of the first flower. For more information, see the press release: www.eso.org/ Two pieces of amber some 110 million years old from public/news/eso1225 northern Spain revealed the oldest record of insect pollina- ESO is by far the world’s most productive ground-based tion, when scientists used X-rays at the European Synchro- astronomical observatory, with its headquarters in Garching tron Radiation Facility (ESRF) to produce detailed images near Munich, Germany, and its telescopes in Chile. For more of two newly described species of tiny insects covered with information, see: www.eso.org pollen grains. Gymnopollisthrips minor and Gymnopollisthrips For a list of ESO-related articles in Science in School, see: maior are thrips (Thysanoptera), minute insects that feed on a www.scienceinschool.org/eso variety of plant and animal sources, including pollen. These Artist’s impression of E-ELT in its enclosure particular thrips are thought to have fed on the pollen of Cy- on Cerro Armazones, a 3060 m mountain- cadopites, a now extinct genus of gymnosperm that related to top in Chile’s Atacama Desert cycads – the plants that look like a giant cross between palm and fern trees and make up the ‘forests’ in dinosaur films. To learn more, see the news item on the ESRF website (www.esrf.eu), use the direct link (http://tinyurl.com/thrips), or read the research paper: E Peñalver et al. (2012) Thrips pollination of Mesozoic gym- Image courtesy of ESO / L Calçada nosperms. Proceedings of the National Academy of Sciences of the United States of America 109(22): 8623-8628. doi: 10.1073/ pnas.1120499109 Situated in Grenoble, France, ESRF operates the most powerful synchrotron radiation source in Europe. To learn more, see: www.esrf.eu For a list of ESRF-related articles in Science in School, see: www.scienceinschool.org/esrf

4 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org News from the EIROs Biology ILL: European XFEL: Celebrating the neutron’s The diggers are done 80th birthday First published results from ILL, European XFEL has reached an important milestone. submitted in 1972 Chemistry The construction of the network of tunnels, totalling Steiner & Dorner nearly 5.8 km in length and extending 3.4 km from (1973) Hamburg-Bahrenfeld to Schenefeld in Schleswig-Holstein, Germany, is now finished. This year, the As Professor Massimo Altarelli, managing director of world’s flagship European XFEL, commented, “The tunnel construction is one neutron science of the most difficult building phases. We are glad that this facility marks task could be completed according to plan, and that we could the 80th anniver- Physics keep costs within the tight budget we set at the time the sary of James contract was awarded.” Chadwick’s Tunnel construction began in July 2010. In January 2011, a famous discov- second boring machine started to excavate the five photon ery. On 1 June tunnels leading into the experiment hall. On 14 June 2012, 2012, it will be more than 400 people – including guests from politics and 80 years since science as well as staff from collaborating companies – cel- the publica- ebrated the completion of the tunnel construction.

tion of Cambridge physicist James General science European XFEL is a research facility currently under construction Chadwick’s famous Nobel Prize-winning paper, which in the Hamburg area in Germany. It will generate extremely proved the existence of the neutron. Chadwick’s discovery intense X-ray flashes for use by researchers from all over the led to the development of neutron research, which continues world. To learn more, see: www.xfel.eu to make breakthroughs across the sciences. This year also For a list of Science in School articles relating to European XFEL, marks the 40th anniversary of the use of Chadwick’s famous see: www.scienceinschool.org/xfel particles at the Institute Laue-Langevin (ILL). As Professor Andrew Harrison, director general of the Celebrating the arrival of the tunnel-boring institute, explains: “Thanks to Chadwick’s discovery and the machine AMELI in the final reception shaft technology developments that have taken place since, ILL

Image courtesy of European XFEL on 4 June 2012 can use neutrons as if they were super X-rays, to understand the world at the atomic level and make discoveries that improve our lives. The neutrons we produce and the world- leading instruments that detect them are delivering impact in areas as varied as health care, the environment and engineering, as well as improving our fundamental knowledge of how the world works.” See the research paper describing the first published results from ILL: Steiner M, Dorner B (1973) Spin wave measurements in the

one-dimensional ferromagnet CsNiF3. Solid State Communica- tions 12(6): 537-540. doi: 10.1016/0038-1098(73)90652-2 ILL is an international research centre at the leading edge of neutron science and technology, based in Grenoble, France. To learn more, see: www.ill.eu For a list of ILL-related articles in Science in School, see: www.scienceinschool.org/ill

To learn how to use this code, see page 65.

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 5 Image courtesy of B.K. Dewey; image source: Flickr Image courtesy of SteveD.; image source: Flickr

Turtle shells are traded illegally in Brazil Cracking down on Image courtesy of Joachim S. Müller; image source: Flickr wildlife trafficking The genitalia of river dolphins are highly prized in Brazil, Biologist Juliana Machado Ferreira as they are believed to have aphrodisiac properties is using science to combat wildlife traffickers in Brazil.

By Nina Notman

he illegal wildlife trade in Brazil is one of the main threats to the country’s fauna, explains biologistT Juliana Machado Ferreira. It is estimated that each year 38 million animals, mainly birds, are removed and souvenirs: for example, items from their natural habitats in Brazil made with turtle shells, teeth, claws, to be sold for a variety of different feathers, fur and skin. The second sought after, because people think that purposesw1. This illegal market is category is for use in traditional they will attract love.” estimated to be worth US$2 billion per medicines. “People think that the The third is bio-piracy: the unfair year. craziest things will cure them or even exploitation of Brazil’s biodiversity “There are four main categories of make them more sexually active,” and local knowledge. “Local people illegal wildlife trade in Brazil,” ex- says Juliana. “For instance, in Brazil, may know which kinds of plants or plains Juliana. The first is for products the genitalia of river dolphins are very animals will cure them of an inflam-

6 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Feature article Image courtesy of Bjørn Christian Tørrissen; image source: Wikimedia Commons Biology

Macaw feathers are a valuable Jaguar teeth are sold commodity in the Brazilian in the Brazilian illegal illegal wildlife trade wildlife trade

mation or other health problem,” she anti-inflammatory activity. “They then to supply the pet market. “In Bra- explains. “Pharmaceutical and cos- patent it and sell the very, very expen- zil, birds are the most sought-after metic companies sometimes exploit sive results back to us as medicine.” group because it’s part of our culture this knowledge, and once they have Such practices contravene the 2010 to have song birds, macaws and learned that traditional people use, agreement in Nagoya, Japan, by the parrots in cages at home,” she says. for example, a frog’s poison to treat an Convention on Biological Diversity, Other animals stolen for this purpose inflammation, they smuggle the frog which states that the benefits aris- include fish, reptiles, amphibians, or the poison back to the lab.” There, ing from the use of genetic resources spiders and small mammals. Some attempts are made to identify and should be shared in a fair and equita- species of pet can be purchased le- then synthesise the active molecule ble wayw2 (Rau, 2010). gally from commercial breeders, but – the molecule responsible for the The fourth and largest category the illegal market is still extremely of illegal wildlife trade in Brazil is large. “One reason is that animals

Biology pet or to bring souvenirs back from 2. What solutions are offered in the Ethics their holidays. article to combat wildlife traf- Ages 11-19 Based on the article, class discus- ficking? This article about the battle against sions could cover the politics of 3. Which methods did Juliana use illegal wildlife trafficking addresses Brazil, the rights of local people, to discover the origin of the a topic of social and political im- the impact of the wildlife trade, and captured birds? portance, involving many biological how to control it. The text can also 4. Why may it be important to re- aspects such as ecology, molecular be used as an excellent example of biology, genetic fingerprinting and turn rescued animals to the area how molecular biology is being ap- population dynamics. It raises im- they originated from? plied to the conservation of endan- portant questions about the exploi- gered species. 5. Describe the steps of Juliana’s tation of indigenous knowledge by work to investigate the genetics pharmaceutical companies. At an 1. What are the four main cat- of the captured birds. everyday level, it can be related to egories of wildlife trafficking in the wish of many children to own a Brazil? Friedlinde Krotscheck, Austria REVIEW

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 7 Blue-fronted Amazon parrots that were seized by the São Paulo highway patrol in 2006 and arrived at SOS Fauna as chicks. The parrots are now fully rehabilitated and were taken to the release site in July 2012. They will stay in acclimation for a month and should be released in mid- August 2012 Image courtesy of SOS Fauna This picture was taken at the police station, immediately after a lorry carrying 4000 trafficked animals was seized by the São Paulo state police and SOS Fauna Images courtesy of SOS Fauna

animals in centres for the rest of their lives is to return them to the wild. In the past this has been deemed too risky, for both the released animal and the natural habitat. But the work Image courtesy of Dario Sanches; image source: Flickr of Juliana and her peers shows that re-release is possible. This isn’t a new idea globally, notes Juliana, but in Brazil it is still a big issue. One of the birds rescued by the Where should the rescued birds be São Paulo state police and SOS released, though? Is it important (or Fauna, still in the box it had been even possible) to return individual trafficked in birds to the area that they came from, or could they be released into any bred in captivity are always more suitable habitat? The answer depends expensive than ones caught from on the ecology, behaviour and genet- A green-winged saltator nature,” Juliana explains. The animals ics of the species, in particular on how are captured all over Brazil and sold isolated and differentiated the populations of that species are. mainly in large cities such as Rio de genetic recombination. Either of these When populations are isolated from Janeiro and São Paulo. outcomes will make the birds less able each other and their environments The other reason why the problem to survive in their environment. differ, they can evolve significant lo- is particularly large in Brazil, says In contrast, if populations of a cal adaptations. For example, chicks Juliana, is because of weak environ- species are not isolated and their need to hatch at a time when food is mental legislation. It can be hard for behaviour, ecology and genetics are plentiful, so in colder regions they will the authorities to prove that animals very similar, releasing individuals into normally hatch later in the year than are illegal, and traffickers only have to the ‘wrong’ population is unlikely to in warmer regions. The populations pay small fines if they are caught. cause genetic problems. may also evolve what are known as Even when the police do seize il- During her recently completed co-adapted gene complexes: groups of legally trafficked animals, the ques- PhD, Juliana investigated the genetic gene variants that work well together, tion remains of what to do with them. similarity between populations – and but not as well when mixed with There are government assessment thus the likelihood of outbreeding other variants of the same genes. and rehabilitation centres, but the depression if individuals are re- If rescued birds from one isolated scale of the problem – in 2002 alone, leased into the wrong population – of population are released to breed with 45 000 animals (of which 37 000 were two exploited bird species: Paroaria individuals from another population, birds) were received by these centres dominicana (the red-cowled cardinal) the result may be outbreeding depres- – means they are very costly to run. and Saltator similis (the green-winged sion in subsequent generations. This Currently, the ‘solution’ proposed by saltator). She travelled all over Brazil can result either from a disruption the Brazilian Ornithological Society is to collect blood samples from birds in in biological cycles (e.g. the chicks to euthanise all animals from non- different areas and then studied their hatching before there is enough food endangered species, which Juliana genomes to see if an individual bird’s available) or from the co-adapted gene strongly opposes. The alternative origin could be identified. Instead of to mass euthanasia or keeping the complexes being broken up during

8 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Feature article Biology Image courtesy of Dilson Santos; image source: Flickr

Image courtesy of Erica Pacifico

A red-cowled cardinal After trapping a bird, Juliana measures it, attaches a leg band for iden- tification, takes a tiny blood sample, disinfects the puncture site, rehy- Next, Juliana needed to collect blood samples, clean it and quan- drates the bird and then releases it blood samples from the two species tify it, and then – using a technique of birds from all across Brazil to work called the polymerase chain reaction out if the differences between the gene (PCR), which mimics DNA replica- sequences in these highly variable section – I increased the amount of only looking at the whole genome (which tions of the genome were sufficient to those fragments I was interested in,” would largely be the same for every allow a bird’s origin to be identified. Juliana explains. For the PCR, Juliana bird sampled), Juliana focused on To find the birds in each region, she used the primers she had identified sections of the genome that are highly would trek for miles playing a record- earlier to allow the correct part of the variable and evolving very quickly. ing of a male bird’s song. “When a genome to be replicated. Her first task was to identify these bird hears the song of the same spe- Next, she looked for any differ- highly variable regions. “I had to find cies but coming from another individ- ences between these specific sections these hypervariable regions in each ual, it goes crazy, as it needs to defend of DNA in the individual birds. This species’ genome,” Juliana explains. its territory,” she says. The bird is then process is called genotyping. The dif- She did this by breaking up the ge- captured using very fine nets, and tiny ferences Juliana was looking for were nomes of the birds into small pieces – microlitre sized – blood samples are variations in the number of repeating and placing them in bacteria. She then taken, after which the puncture site is units. As mentioned previously, these ‘fished’ for highly variable regions disinfected and the bird rehydrated highly variable sections are blocks of using probes of complimentary DNA before being returned to the wild. In

strands. But how did Juliana know total, Juliana collected samples from Image courtesy of Marcos Antonio Melo what type of genetic sequence to fish 10 different birds in each sample for in the first place? “One of the char- site and also received donations of acteristics of these variable regions is museum tissue samples and blood that they have repetitive units,” she samples from other researchers – from explains. “So we used probes that are more than 500 birds in total. repetitive as well, for example blocks Once her collection was complete, of AGAGAGAG or GATAGATAGA- Juliana returned to the lab to analyse TA.” Once the highly variable sections the samples. “I went through a period had been identified, new probes that of very intensive lab work during are more specific (called primers) which I had to extract DNA from the could be designed so that these sections could be directly targeted in the future. (To learn more about the tech- Juliana with a green-winged saltator (Saltator nique, see Müller & Göllner-Heibült, similis), which she is about to release 2012.)

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 9 repetitive units such as AGAGAGAG. Examples of possible actions include Juliana would like to thank her PhD

“One person has (AG)3 while another road blocks to check for traffickers advisor, Dr Joao Morgante, the US

may have (AG)7,” Juliana explains. leaving the area with wildlife, more Fish and Wildlife National Forensics Once each bird had been genotyped, environmental legislation and social Laboratory and São Paulo State Police Juliana used statistics to analyse the work with the local communities, she for their support. She is also grate- variation in the population across the explains. ful for the research funding from the whole of Brazil. “Some of the ques- It is these sorts of applications Brazilian federal research funding tions that could be answered were: that first encouraged Juliana to enter agencies CAPES and FAPESP. how many different genetic groups conservation research, after she had are there in this sampling? Are they spent years volunteering with the References correlated to geography? How differ- non-government organisation (NGO) Müller S, Göllner-Heibült H (2012) ent are they? Are they isolated from SOS Faunaw3, working closely with its Genetic fingerprinting: a look each other? What is the within-group president, Marcelo Pavlenco Rocha. inside. Science in School 22: 49-56. variability compared to the total vari- Through SOS Fauna, she attends www.scienceinschool.org/2012/ ability?” she says. raids to assist the police in identify- issue22/fingerprinting On the basis of this information, ing which species are legal to own, Juliana was not able to tell where in- helps with release projects, and is a To learn about the lead-up to COP 10, dividuals of S. similis had come from. spokesperson against animal traffick- the 10th meeting of the Convention This means that her genetic analysis ing. More recently, she has established on Biological Diversity, at which the cannot be used to assign captured another NGO called Freeland Brasil. Nagoya Protocol was agreed, see: birds to their home population, but it Through this organisation, Juliana is Rau M (2010) Homo sapiens – an also means that returning birds to the involved in making public policy, in endangered species? Science in ‘wrong’ population should not cause projects to train people from different School 15. www.scienceinschool. genetic problems. sectors on how they can combat wild- org/2010/issue15/biodiversity The situation for P. dominicana was life trafficking, and in seeking funding a little different. Juliana was able to to establish an independent wildlife Web references identify three major genetic groups forensics lab in Brazil. that were correlated to distinct Juliana’s story demonstrates just w1 – The extent of the illegal wildlife geographical areas. Although these how much one determined young trade in Brazil was estimated by the groups were recognisable, they were person can achieve, with a great deal NGO RENCTAS, the Brazilian na- not isolated: there were high levels of devotion and effort. But surely we tional network to fight the traffick- of gene flow between them. So even too can help to end wildlife trafficking of wild animals. www.renctas. though it is possible to tell roughly ing? Juliana has two requests to all of org.br where captured birds had come from, us. First, remember that wild animals w2 – Adopted in October 2010, the there would be little likelihood of are not pets; if you want a pet, keep a Nagoya Protocol on Access to outbreeding depression if they were domestic animal. Second, make sure Genetic Resources and the Fair released elsewhere. Image courtesy of Diego3336; image source: Flickr you know the sources of the things and Equitable Sharing of Benefits During her PhD, Juliana was able to that you buy, whether pets or wildlife- Arising from their Utilization to the apply her research directly to the bat- based products. “If you really need to Convention on Biological Diversity tle against illegal wildlife trafficking. have an animal or if you really need to is an international agreement which “I was able to track the origin of 49 P. buy that comb, find out whether it is covers appropriate access to genetic dominicana individuals seized in São from a legal breeder or a legal source,” resources and transfer of relevant Paulo; they were all part of the same she says. “Ask whether it is okay for technologies, taking into account all genetic cluster,” she says. “This infor- them to be selling this tortoise-shell rights over those resources and to mation corroborates what the police comb or that red coral necklace.” technologies. See: www.cbd.int/abs think is the most exploited region for this species.” As well as helping the Acknowledgement authorities decide where to return the This article is based on an interview birds to, knowing the areas that are given by Juliana Machado Ferreira to A night-time skyline in São Paulo the most exploited allows efforts to be the editor-in-chief of Science in School, – areas of which are hot spots for made there to prevent exploitation. Dr Eleanor Hayes. illegal wildlife trafficking

10 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Feature article

w3 – SOS Fauna is a non-govern- In 2010, Juliana Machado Ferreira Biology mental, non-profit organisation gave an online lecture about her that works to defend and conserve work to save birds and other animal Dr Nina Notman is a science writer the wildlife of Brazil. See: www. stolen from the wild in Brazil. and editor. After her PhD in synthetic sosfauna.org/index-en.php See: www.ted.com/talks/juliana_ organic chemistry at the University Resources machado_ferreira.html of Bristol, UK, she started a career in The Freeland Foundation is an inter- The Convention on International publishing, managing the peer review national organisation dedicated to Trade in Endangered Species of process of a number of the UK’s Royal stopping human and wildlife traf- Wild Fauna and Flora (CITES) is an Society of Chemistry journals. She then moved into science journalism, ficking. See: www.freeland.org international agreement between governments to ensure that the working on the society’s flagship Inspired by the Freeland Founda- international trade in specimens of magazine, Chemistry World. In early tion, Freeland Brasil is dedicated wild animals and plants does not 2012, she left the magazine and went to preserving Brazil’s unique and threaten their survival. See: freelance. important biodiversity. See: www.cites.org www.freelandbrasil.org.br If you enjoyed this article, why not Traffic, the wildlife trade monitoring browse the other feature articles network, works to ensure that trade in Science in School? See: To learn how to in wild plants and animals is not a use this code, see www.scienceinschool.org/features threat to the conservation of nature. page 65. See: www.traffic.org

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 11 The vessel in which the JET experiment takes place is shaped like a doughnut

o h P t e Seeing the light: b r e h

monitoring fusion e

Image courtesy of EFDA-JET

a m experiments I

Finding out what is going on in the core of a fusion experiment at 100 million degrees Celsius is no easy matter, but there are clever ways to work it out.

By Phil Dooley, EFDA-JET

he Joint European Torus, JET, and tritium into the heavier element is the world’s largest nuclear helium. Forcing the atoms to fuse fusion experiment, just outside takes a huge amount of energy, but The inside of the JET vessel during a OxfordT in the UK. As described in a the fusion process itself releases yet high-power pulse. The plasma core is previous article (Rüth, 2012), our sci- more energy. transparent because the hydrogen iso- entists are developing a clean energy Inside the experiment, the fuel topes are completely ionised, so there source for the future, involving the (usually deuterium alone; the mix- are no electron transitions providing fusion of light atoms in a doughnut- ture with radioactive tritium is used visible radiation – except for a small visible wisp of cooler plasma on the shaped vessel nearly six metres across. only occasionally) is heated until the inside lower edge This is not splitting the atom and electrons are stripped off their nuclei. there is no uranium involved – we This ionised gas is called plasma and fuse the hydrogen isotopes deuterium is the ideal environment for the colli- Image courtesy of EFDA-JET

A simplified image of the JET experiment. A: a cutaway image of JET’s doughnut-shaped vessel. B and C: horizontal and vertical bolometer arrays are shown in red. The lines denote the lines of sight of the

12 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Cutting-edge-science

sions between nuclei that are required o for fusion. The plasma is ten times h Physics P t e hotter than the core of the Sun and b r Chemistry e h races around the vessel, twisting and S k Nuclear energy n i tumbling in an intricate magnetic cage

o Ages 15-18

woven by the scientists who control

e t

r the machine.

u Following on from a previous article (Rüth, 2012), this article gives a

e Creating matter this hot is a major

g clear picture of some of the wealth of detectors used in nuclear fusion

a m

I achievement, but keeping it confined research. Teachers can use this article to provide information about long enough for a significant number how fusion can be monitored, and what difficulties and challenges of fusion reactions to happen is even scientists face when working at such high temperatures. more challenging – both because of Suitable comprehension and discussion questions include: the extremely turbulent nature of · Why is a high amount of energy required for fusion to occur? plasma this hot, and because of its · What type of material has to be used for the chamber walls? Why? tendency to pick up impurities from the components inside the vessel. · Which devices are used to monitor what is happening inside the Hence, sophisticated control mecha- plasma? Physics nisms have been developed to moni- · How is the plasma confined within the walls and kept at a safe tor the plasma’s every facet during distance from them? operation, make adjustments to keep · How can leakage of energy be detected? it stable and clean where possible, or The discussion with students could then be taken further by address- terminate it if it gets too turbulent (see ing environmental impacts, sustainability and the importance of such EIROforum, 2012). experiments. But how do we know what is going Catherine Cutajar, Malta on inside this sealed vessel at 100 mil- REVIEW lion degrees Celsius? Any measuring device that you tried to put into the plasma would be destroyed – sub- cameras, sensors, detectors, lasers, ion JET’s gamma-ray limed into plasma in seconds. Even detector works in a similar beams and coils – to name a few. We looking at the experiment through the way to a Geiger counter, sealed windows of the vessel is less will discuss some of these systems in shown here. A Geiger coun- informative than you might expect, as this article. ter is used to measure various the hot plasma is almost transparent. forms of ionising radiation, This is because the core of the plasma We have fusion! Gamma rays including gamma rays is so hot that all the electrons have The main product of a fusion

been stripped off their nuclei, so no reaction is fast neutrons. As well as Image courtesy of Radioactive Rosca; image source: Flickr electron transitions – the source of vis- measuring the number of neutrons, ible light – are possible. we always cross-check the number of However, there are many other fusion reactions with a second meas- ways to find out what is happening in ure, the number of gamma rays. In the plasma. Our understanding of this addition to the main reaction between jumble of high-speed particles comes deuterium and tritium, during fusion, from about one hundred diagnostics: many other reactions occur in small proportions in the hot plasma, some of which leave the nuclei themselves in excited energy states. Just like elec- bolometers. D: the horizontal trons in excited energy levels, these gamma-ray detection system is shown nuclei then release their energy in the in blue, channelling the radiation form of electromagnetic radiation. away from the vessel through the Because nuclear energy levels are very surrounding thick concrete walls to energetic, gamma rays are released the detector system, which is in a separate hall rather than the visible or UV light emitted by electrons.

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 13 Image courtesy of daynoir; image source: Flickr

Magnetic fields keep the im- mensely hot plasma away from the vessel wall. These fields are many times larger than those of this bar magnet, made visible by iron filings

core will deplete energy from the most important area. A single bolometer cannot distinguish between radiation from the core or the edge, but with a number of them, it is possible to build up a detailed 3D map of the radiation sources. This is achieved by putting each bolometer behind a couple of pinholes to narrow down their field Gamma rays pass straight through preventing the energy from escaping of view. Then the results from all the most cameras, so a specialised detec- from the plasma. Even if we keep different views – some through the tion system is needed. The experiment the particles confined, significant middle, some just grazing the edge of is surrounded by 2 m thick concrete amounts of energy can leak from the the plasma, and so on – are combined walls to contain the radiation, but a plasma in the form of electromagnetic with some clever processing to build long pipe channels some radiation radiation. Although it looks transpar- up a 3D image. This construction of through the walls to the detection ent, the plasma does give out a lot of a 3D image from lots of individual laboratory. Here, we use a system radiation that we can’t see. To meas- measurements is a similar technique similar to a Geiger counter, which ure this radiation leakage, we need a to that used in medical computed generates an electric current when device that, unlike our eyes, can see tomography (CT) scans, where a 3D gamma rays pass through a small radiation at all wavelengths. We use a image is compiled from many single chamber, ionising the gas inside. We bolometer, which is surprisingly sim- X-rays taken from different angles. count the electrical pulses from two ple – just a tiny strip of metal. Electro- systems – one with a vertical view of magnetic radiation of any sort – e.g. Watching out for hot spots: the chamber, the other horizontal – radio waves, UV radiation or gamma cameras which tells us how many fusion reac- rays – heats the metal, and changes its resistance, which is easily measured. It seems astonishing that a plasma tions have occurred, and where in the Image courtesy of Samantha Decker; image source: Flickr One of the main causes of the radia- chamber they took place. at more than 100 million degrees tion is impurities in the plasma, most Celsius can be contained within a of which originate from the walls of metal vessel. Yet the huge magnetic Measuring energy leakage: the vessel. It is important to find out fields created by the coils around JET bolometry where the impurities end up – on succeed for the most part in keeping One of the keys to a successful the edge of the plasma is not a big the plasma away from the vessel wall, fusion experiment is confinement – problem, but impurities in the hot which was recently refurbished with

14 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Cutting-edge-science

Image courtesy of EFDA-JET Physics source: Wikimedia Commons source: Wikimedia Image courtesy of Derek Jensen; image

An infrared view of the JET vessel during an experiment, showing hot spots where the plasma is The indication that the plasma has touching the wall moved too close is a hot spot on the wall, which gives out what is known as black body radiation. To the human beryllium tiles that have a melting eye, a hot spot would begin to glow point of merely 1278 °C. One of the red at around 500 °C, and would be keys to the success of this set-up is an orange by 1000 °C. However, it can surroundings. Because most cameras be detected a lot earlier, because a array of video cameras used to ensure can detect infrared radiation (using hot spot will emit infrared radiation that the plasma does not get too close what is often called the night vision to the vessel wall. as soon as it becomes hotter than its setting), a protection system has been developed that uses cameras to monitor for infrared hot spots. If one begins to develop, the plasma can be More about EFDA-JET adjusted – for example by moving the magnetic field away from the wall or by turning down the power to reduce the temperature – before any damage is done. As a joint venture, the Joint European Torus (JET)w1 is collectively used by more than 40 European fusion laboratories. The European Fusion Develop- Supporting activity: visualising ment Agreement (EFDA) provides the platform to exploit JET, and more than infrared light 350 scientists and engineers from all over Europe currently contribute to the Most cameras are sensitive in the in- JET programme. frared – even those in mobile phones. EFDA-JET is a member of EIROforumw2, the publisher of Science in School. Shine a TV remote control at a camera See all EFDA-JET-related articles in Science in School. and you can see the infrared radiation www.scienceinschool.org/efdajet signalling its special code for the TV. Next, show that the wavelength of electromagnetic radiation determines

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 15 Image courtesy of EFDA-JET Image courtesy of EFDA-JET

Unlike your eyes, a digital camera Although visible light from a will register the infrared radiation torch is absorbed by cola, infrared from a TV remote control radiation is not

how well it can pass through a mate- w2 – EIROforum is a collaboration If you enjoyed this article, why not rial – which is why we need different between eight of Europe’s largest in- browse the other cutting-edge sci- types of detector to monitor the differ- ter-governmental scientific research ence articles in Science in School? See: ent types of radiation emitted by the organisations, which combine their www.scienceinschool.org/ reactor. Shine a torch through a glass resources, facilities and expertise to cuttingedge of cola: the visible light from the torch support European science in reach- is absorbed by the drink, which still ing its full potential. As part of its appears brown. Then shine the remote education and outreach activities, Dr Phil Dooley is the news and control through the cola while watch- EIROforum publishes Science in education officer at EFDA-JET. He ing with the camera: the infrared light School. To learn more, see: was born in Canberra, Australia, and travels through the liquid more or less www.eiroforum.org completed a PhD in laser physics at unaffected. the Australian National University. Resources To escape academia he took a job in References IT in Rarotonga, Cook Islands, for 18 Warrick C (2006) Fusion – ace in the months, before returning to Australia EIROforum (2012) Bigger, faster, hot- energy pack? Science in School 1: 52- and working in software training. ter. Science in School 24: 2-5. www. 55. www.scienceinschool.org/2006/ His love of science drew him back to scienceinschool.org/2012/issue24/ issue1/fusion eiroforum physics, this time as a communicator, Browse the whole series of Science in running the school outreach pro- Rüth C (2012) Harnessing the School articles about fusion in the gramme at the University of Sydney. power of the Sun: fusion reactors. Universe. www.scienceinschool. In October 2011 Phil joined the EFDA- Science in School 22: 42-48. org/fusion JET team in Oxfordshire, UK. www.scienceinschool.org/2012/ For an introduction to the electromag- issue22/fusion netic spectrum and how it is used in Web references astronomy, see: Mignone C, Barnes R (2011) More w1 – More information is available on than meets the eye: the electromag- the EFDA-JET website. See: netic spectrum. Science in School To learn how to www.efda.org/jet 20: 51-59. www.scienceinschool. use this code, see page 65. Image courtesy of EFDA-JET org/2011/issue20/em

16 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Cutting-edge-science

Behind Biology the autism spectrum Image courtesy of Norma Desmond; image source: Flickr

The autism awareness ribbon. The jigsaw puzzle pattern symbolises the complexity of the autism spectrum Image courtesy of Melesse; image source: Wikimedia Commons

Research into the everyone called him ‘the professor’. ised that Peter didn’t laugh at jokes, Peter knew a great deal and read a lot; avoided eye contact and grew angry genetics of the to the others he seemed to be a genius. if he couldn’t sit in the same seat. The However, he didn’t make friends camp manager thought Peter might autism spectrum easily and mainly played alone. Staff have autism. His parents then admit- is increasing our became concerned when they real- ted that Peter had been diagnosed understanding of these conditions, Biology and may lead Ages 16+ to better ways This informative article gives an insight into the autism spectrum disorders (ASD) and their distinguishing features. It is helpful as a source to diagnose and of information for any teachers who have students with ASD, for understanding the genetic mutations associated with ASD, and as an manage them. example of how genetics and environment can affect phenotype. The article could be used in biology lessons about the brain or behaviour, or in discussions of synaptic plasticity. Suitable comprehension By Andreas Chiocchetti questions include: 1. How do studies show that autism is largely inherited? he first time I encountered au- 2. What are the risk factors for autism? tism was in the summer of 2004 while working as a children’s 3. What kind of genetic variations are linked to autism? Shaista Shirazi, UK Tcamp counsellor. That year, one boy REVIEW stood out. His name was Peter, but

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 17 with Asperger’s syndrome but that Social Figure 1: Autism spectrum they hadn’t mentioned it because disorders are defined by Peter was so keen to attend the camp. social, communication and Image courtesy of Andreas Chiocchetti ‘The professor’ was able to stay behavioural impairments and Difficulty are associated with a range of in interacting until the end of the camp and we all with others symptoms learned a lot from him. Preference for being alone Strange Asperger’s syndrome is one of a Lack of attachment group of similar disorders eye contact to objects Lack of response My experiences with Peter made me to verbal cues Lack of fear want to understand and research the

Lack of response to biological basis of Asperger’s Syn- normal teaching Insistence on drome. This is one of three disorders methods consistency Inappropriate use with similar, but distinct, symptoms of language (see box), which are classified as au- Communication Strange mannerisms Behavioural tism spectrum disorders (ASD). ASD

The autism spectrum disorders

Autism spectrum disorders (ASD) are defined by cer- – Asperger’s syndrome, early childhood (or classical) tain communication, social and behavioural difficul- autism and pervasive developmental disorders not oth- ties (figure 1). ASD is a ‘spectrum’ because different erwise specified (PDD-NOS) – with varying symptoms people experience the symptoms differently, and with and severity (figure 2 and table 1). varying degrees of severity. There are three sub-types Weak symptoms

Figure 2: The three sub-types of ASD vary in PDD-NOS the severity of their symptoms and mental impairment. People diagnosed with early Asperger’s syndrome childhood (classical) autism display a range of symptoms, such as those in figure 1. High IQ IQ 70 Low IQ Asperger’s syndrome has similar symptoms Classical autism to early childhood autism, but with normal language development and IQ. PDD-NOS is the mildest form and is often referred to as atypical autism or sub-threshold autism Strong symptoms

Early childhood (or classical) autism Asperger’s syndrome PDD-NOS

Onset Early childhood Usually later onset Not specified

Social level Impaired Impaired At least two of these Language level Impaired Not impaired three are affected Behavioural level Impaired Impaired

IQ High functioning: IQ > 70; IQ > 70 IQ > 35 low functioning: IQ < 70

BACKGROUND Table 1: Differences between the three sub-types of autism spectrum disorders

18 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Image courtesy of paulaphoto / iStockphoto

Cutting-edge-science Biology

Image courtesy of Norma Desmond; image source: Flickr

starts in early childhood and continues throughout adulthood. Sometimes people are not aware that they have ASD heritability it. Common symptoms include lack of eye contact and difficulties maintain- Twin studies have shown that the cause of ASD is largely genetic (up to 80 %). These studies analyse twins who have grown up together ing relationships, often combined with where at least one child has ASD. Monozygotic (identical) twins have learning difficulties (figure 1). It can the same genetic information, whereas dizygotic (non-identical) twins be hard for sufferers to integrate into are more like normal siblings: they share around half of their genetic society or to live independently. information but have experienced many of the same environmental factors (e.g. parents and home care). ASD has both genetic and If a disorder has a purely genetic basis, it will always affect both mo- environmental causes nozygotic twins. In dizygotic twins, if one has a genetic disorder there ASD prevalence in the general is a 50 % chance that the other twin will have it too. Studies have population is estimated at about 1 % shown that if one twin has ASD, the chance of the other twin being and rising, mainly due to increased affected is around 80 % for identical twins, and about 30 % for non- awareness and a broader diagnosis. identical twins; these figures include both the genetic contribution It is estimated that up to 80 % of ASD and the effect of the environment that was shared by the twins. From has a genetic basis (see box). Geneti- these data, the average genetic contribution to ASD has been esti- cists believe that ASD is caused by a mated to be 50-80 %. The remaining contribution is environmental, combination of different variations in so to develop ASD, a person would usually need both a genetic pre-

several genes, rather than one single BACKGROUND disposition and an environmental trigger. mutation or gene variant. If 80 % of ASD is genetic, the other 20% must be explained by environmental factors. Only a few environ- Another risk factor for ASD is gen- activated during male development. mental factors have been proven to der: boys are four times more likely Some other disorders, such as increase the risk of ASD, including to be diagnosed with ASD than girls. fragile X syndrome, show similar symptoms to ASD: around 50 % of parental age and rubella infection Perhaps some risk factors are carried people with fragile X have autism-like during pregnancy. Despite the widely on the X chromosome (of which males publicised scare in the UK, however, symptoms. Fragile X patients have a only have one copy, meaning they known mutation in the FMR1 gene, there is no evidence to suggest that have no second, healthy, chromosome which alters a protein essential for vaccines increase the risk of develop- to compensate) or in genes that are ing ASDw1, w2. normal brain function.

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Image courtesy of illuminaut; image source: Flickr

ASD is linked to synaptic plasticity, which is crucial for learning, memory, emotional recognition and use of language

ASD is linked to synaptic Genetic diagnosis provides hope ations in children and families with plasticity for better treatment psychiatric disorders such as atten- Genetic research on ASD focuses Currently ASD is diagnosed by tion deficit / hyperactivity disorder on identifying variations linked to interviewing the parents and observ- and ASD. In 2007, he graduated in ASD. Researchers are genotyping ASD ing the ASD sufferer. The diagnosis biotechnology and genetics from sufferers and their parents to identify can be influenced by the parents or the University of Salzburg, Austria, the inheritance patterns of particular the psychiatrist’s personal bias. It is and then gained a PhD in proteomic high-risk alleles. My collaborators also a very time-consuming process. biomarkers in ASD at the German and I are also comparing the DNA Therefore, a fast, objective and reliable Cancer Research Center in Heidel- diagnostic tool is needed. of healthy people with the DNA of berg, Germany. Knowing which genes or genetic people diagnosed with ASD. variations are responsible for ASD Studies have identified several rare makes it possible to design new diag- Web references mutations and single nucleotide poly- nostic tools. Understanding the molec- morphisms (SNPs, which are more w1 – Wikipedia offers a good over- ular mechanisms involved might also common; see box) linked to ASD. view of the controversy surround- enable new medications or treatments Geneticists have also discovered that, ing the combined measles, mumps to be developed. Personally, my main in ASD sufferers, copy number vari- and rubella (MMR) vaccine. See reason for doing this research is to ations (CNVs; see box) affect coding http://en.wikipedia.org/wiki/ explain the biological basis of ASD to regions of DNA more often than in the MMR_vaccine_controversy both ASD sufferers and the general general population. public to help reduce the stigma as- w2 – The British medical community By analysing the proteins that these sociated with the condition. also responded to the MMR scare. genes encode, we have shown that See: www.bmj.com/content/342/ they are important for energy metabo- bmj.c7452 lism, protein synthesis and signalling Dr Andreas Chiocchetti was born in neurons. It seems that these vari- in South Tyrol, Italy, and is head of Resources ations affect the ability of brain cells the molecular genetics laboratory at to make and maintain connections. the University Hospital for Child and This novel is told from the point This process, called synaptic plastic- Adolescent Psychiatry, Psychosomat- of view of a boy with Asperger’s ity, is crucial for learning, memory, ics and Psychotherapy in Frankfurt, syndrome: emotional recognition and the use of Germany. There, his research focuses Hadden M (2004) The Curious language. on the characterisation of genetic vari- Incident of the Dog in the Night-Time.

20 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Cutting-edge-science Biology

A A A A A A A A A A A A C C C C C C C C C C C C A C A C A C A C A C A C A A A A A A A A A C A C A C A C A C A C C T C T C T C T C T C T C A A A A A A G C C C C C C Genetic variation C TC C TC C TC C TC C TC C TC C A GC C A G C C A G C C A G C C A G C C A G C C A C CA G CA G CA G CA G CA G CA G A T C C T C C T C C T C C T C C T C C T C C C C C C C T T T T T T T TC C TC C TC C TC C TC C TC C G GC A A G C A A G C A A G C A A G C AA G C AA G C T T T T T T G G G G G G G GCA A GCA A GCA A GCA A GC A A GC A A C C T C T C T C T C T C T C T C T C T CT C T CT C T G G G G G G C C C C C C C CTC T CTC T CTC T CT C T CT C T CT C T T A A G C A A A G C A A A G C A A A G C A AA G CA AA G CA AA G C C C C C CA A A A A A A A A AGC AA AGC AA AGC A A AGC A A AGC A A AG C A G C T C T C T C T C T C T C T C T CT C T CT C T CT C A A A A A AG T T T T T T T C TCT C TCT C TCT C TCT C TC T C TC T C C A A G C A A G C A A G C A A G CA A G CA A G CA A T T T T T TC A A A A A A A C AAG C AAG C AAG C AAG C AA G C AA G A T T C T T C T T C T T C T T C T T C T T A A A A A AT T TC T TC T TC T T C T T C T T C T G A A G A A G A A G A A G A A G A A G A G G AA G AA G AA G AA G A A G A A A C T C T C T C T C T C T C Each of us carries many genetic variations. These vari- C C T C T C T C T C T C T A A A A A A A A A A A A A A A A A A A A A A A A A A T T T T T T T T T T T T T T A A A A A A A ations include single nucleotide polymorphisms (SNPs) A A A A A A A and copy number variations (CNVs), as well as rare mutations. Mutations are alterations in the genetic code, including deletions and insertions or nucleotide replace- Affected population Control population ments. SNPs occur when one single DNA nucleotide is Affected population Control population Affected populationRare mutations Control population different, e.g. at a particular place in the genome, one Rare mutations person might have an adenine (A), whereas another per- Rare mutations son might have a guanine (G) nucleotide. A A A A A A A A A A A A C C C C C C C C C C C C A C A A A C A C A C A A C A C A A C A C A C A C C C C TA C C C TA C GA C GA C C T A C T A C C T A C G A C G A C TA GA T A C GC C C C GC C GC C GC C C G C C G C C C G C C G C C G C C A A GC A GC A A A A A A A G C A A A A Most people have two copies of each gene, one from G CC T G T CC G CC T CC G G C C G C C T T C C G C C T C C T C C C GC T C C C C C T C G C G C GC T G C T C C C T C G C G C A G T G G G A G A G A G A A G T G A G A G A G C G C A C A C G C G C G C C C G C G C A C G C G C G C CA T C C C A T C A T C A T C A T C A T C C A T C AT C AT C G T TG G TG T G T G G G T T G T G T T A AC AA A A A AC A AC A AC A A A C A A C A A A A C A A C A A C A C C C C C C G C C C C C C TG A TGC A TGC A TG A TG A TG A TG T A T G A T G C A T G A T G A T G A T G A C A AA AA C A C A C A A C A C A A A C A C A C A each parent. However, some people have CNVs: these AC T CC CC C T C T C T C A C T A C T C C C T C T C T C A A A A A A A A A A A C T C TC TC T C G C G C C T C T C T C T C G C G C A A AT AG A A A A A A A A A A A A T A A A A A A A C G C AC AC G C G C G C C G C G C A C G C G C G C T TG TG T T T T T T T G T T T T G C T G T C G C T C G G C G C T T C G C T C T A AC AC A A A A A A A C A A A A G A G G G A G A G A G G A G A G G A G A G A G A A A people might have more than or fewer than two copies C T C C C T C T C T C C T C T C C T C T C T C T T T A A A A A A A A A A A A A A A A A A A A A A A T T A T A T T T T T T T A T T T T of a gene, or might even be missing a sequence entirely. A A A A A A A A A A A A A A SNPs and CNVs are normal, fairly common (particularly in non-coding DNA) and do not usually cause problems. However, some variations, if they are found in or near Affected population Control population

Affected population Control population Image courtesy of Andreas Chiocchetti an important gene, can cause illness. Certain damaging Affected populationSingle nucleotide Control population SNPs, CNVs and rare mutations are associated with ASD polymorphismsSingle nucleotide (SNPs) (figure 3). polymorphismsSingle nucleotide (SNPs)

A A T T A A A A T T A A polymorphismsAA A A A (SNPs)A A A A A A A A T T T T T T T T T T T A A T A A A T A A A A A A A A A A A A A A A A A T T A T T T A T T T T A A A A A A T A T A A A A A A A A A A A A A A A A A A A A A A A A A T T T T T T A T A T T T T T A T A A T A T A T A T A A T A T A T A T A T A T A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A T T TT TT T TT T T T T T A T T T T T T T T T A A A A A A A T A A A A A A A A A T A A A A A A A A A A A A A A A A A A A A A T T T A T T T T A T T T T T A A A A A A T A A T A A A A A A A A A A A A A A A A A A A A A A A A A A A A A Figure 3: Genetic variations and ASD research. Research- T T T T T T A T T A T T T T T T T T T T T T T T T T T A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A T T T T T T T T T A A A A A A A A A A A A A A A A A A A A A T T T T T T T T T T T T ers are investigating three types of genetic variation – A A A A A A A A A A A A A A A A A A A A A A A A A A T T T T T T T T T T T T T T SNPs, CNVs and rare mutations – to assess whether they A A A A A A A A A A A A A A increase the risk of ASD. This figure shows how certain variations, which may also be present within the general (control) population, are more common in people diag- Affected population Control population nosed with ASD. Some variations are very common and Affected population Control population associated with a low risk of ASD, whereas others are AffectedCopy population number variations Control (CNVs) population very rare and considered high risk. The more risk factors Copy number variations (CNVs) (genetic and environmental) a person is exposed to, the Copy number variations (CNVs) more likely they are to be affected by ASD BACKGROUND

London, UK: Random House. ISBN: Bloomington, IN, USA: iUniverse, central figure in the 1988 film Rain 9781400032716 Inc. ISBN: 9780595378579 Man is based on a real person. Fans of Jane Austen’s novels will find Chapter 16 of Bad Science covers the If you have concerns about a pupil, this a fascinating and enlightening MMR scare in the UK: family member or friend, it is advis- study: Goldacre B (2008) Bad Science. able to speak to a doctor or psychia- Ferguson Bottomer P (2007) So London, UK: Harper Collins. ISBN: trist. You should not rely on self- Odd a Mixture: Along the Autistic 9780007240197 diagnosis or web-based diagnostic Spectrum in ‘Pride and Prejudice’. The animated film Mary and Max tools, as there is a lot of misleading London, UK: Jessica Kingsley. ISBN: (2009; Director: Adam Elliot; Aus- information on the Internet. 9781843104995 tralia) tells the curious and touching The following websites, however, may ASD from the perspective of a special story of two unlikely pen pals, Mary be helpful: education teacher: and the autistic Max. The UK’s National Autistic Society Rich L (2005) Casey’s Wall: A Novel. The character of Raymond, the autistic provides information and support

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 21 A neuron (stained in green) in tissue culture. Mutations linked to ASD appear to affect the brain’s ability to make and maintain connections

Image courtesy of GerryShaw; image source: Wikimedia Commons

for people with ASD, and also for 68(11): 1095-1102. doi: 10.1001/ 68(4): 320-328. doi: 10.1016/ their families. See: www.autism.org. archgenpsychiatry.2011.76 j.biopsych.2010.02.002 uk Holt R et al. (2010) Linkage and Pinto D et al. (2010) Functional Autism Speaks is the USA’s largest candidate gene studies of autism impact of global rare copy number autism science and advocacy or- spectrum disorders in European variation in autism spectrum disor- ganisation. See: www.autismspeaks. populations. European Journal of Hu- ders. Nature 466(7304): 368-372. doi: org man Genetics 18(9): 1013-1019. doi: 10.1038/nature09146 If you found this article useful, you 10.1038/ejhg.2010.69 Download the article free of charge may like to browse all the other Leblond CS et al. (2012) Genetic and from the Science in School website medicine-related articles in Science functional analyses of SHANK2 mu- (www.scienceinschool.org/2012/ in School. See www.scienceinschool. tations suggest a multiple hit model issue24/autism#resources), or org/medicine of autism spectrum disorders. PLoS subscribe to Nature today: Readers who are interested in consult- Genetics 8(2): e1002521. doi: 10.1371/ www.nature.com/subscribe ing the primary literature may find journal.pgen.1002521 Weiss LA et al. (2009) A genome- the following articles useful: PLoS Genetics is an open-access jour- wide linkage and association scan Chiocchetti A et al. (2011) Muta- nal, so this article is freely available. reveals novel loci for autism. Nature tion and expression analyses of Lichtenstein P et al. (2010) The ge- 461(7265): 802-808. doi: 10.1038/ the ribosomal protein gene RPL10 netics of autism spectrum disorders nature08490 in an extended German sample and related neuropsychiatric disor- Download the article free of charge of patients with autism spectrum ders in childhood. American Journal from the Science in School website disorder. American Journal of Medi- of Psychiatry. 167(11): 1357-1363. doi: (www.scienceinschool.org/2012/ cal Genetics Part A 155(6): 1472-1475. 10.1176/appi.ajp.2010.10020223 issue24/autism#resources), or sub- doi: 10.1002/ajmg.a.33977 Liu XQ et al. (2008) Genome-wide scribe to Nature today: www.nature. Freitag CM et al. (2010) Genetics of linkage analyses of quantitative and com/subscribe autistic disorders: review and clini- categorical autism subphenotypes. cal implications. European Child & Biological Psychiatry 64(7): 561-570. Adolescent Psychiatry 19(3): 169-178. doi: 10.1016/j.biopsych.2008.05.023 doi: 10.1007/s00787-009-0076-x Pagnamenta AT et al. (2010) Char- Hallmayer J et al. (2011) Genetic acterization of a family with rare heritability and shared environmen- deletions in CNTNAP5 and DOCK4 To learn how to tal factors among twin pairs with suggests novel risk loci for autism use this code, see page 65. autism. Archives of General Psychiatry and dyslexia. Biological Psychiatry

22 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Image courtesy of videophoto / iStockphoto Teaching activities

Mercury and liquid

sy of dem10 / iStockph nitrogen. To familiarise ourte oto ge c Ima students with the differences between solids, liquids and gases, use examples of materials that exist in an unexpected state of matter, such as mercury or liquid nitrogen. This helps to challenge misconceptions such as ‘all metals are solids’. Also point out that air is not the only gas (another common misconception), and that it is in fact a mixture of gases Physics Primary Science Physics Ages 10-13* The effect of heat: The main strength of this article is that it presents a group of activities in an simple experiments order that makes sense as a whole. Even though the activities are likely to be known by many teachers, with solids, liquids the suggested sequence and questions will help teachers approach some and gases rather difficult concepts, Primary such as heat transfer, evaporation and conden- From a homemade thermometer to sation. The activities also knitting needles that grow: here are some help teachers to examine the reversibility of some simple but fun experiments for primary- of these processes. Anoth- er important advantage of school pupils to investigate what happens this article is that it uses feasible and easy experi- to solids, liquids and gases when we heat ments, which can be carried out using standard them. school equipment and cheap materials. By Erland Andersen and Your students will have answers to all Christiana Nicolaou, of these questions once they have un- Andrew Brown Cyprus derstood how heat affects solids, liquids and gases. In this small collection hy do elephants squirt wa- of experiments, we begin by investi- *Note that the authors sug- ter onto their backs? How gating how heat alters the properties gested using the activities with younger students, aged 7-11. does fog form? And why of the three states of matter. We then REVIEW Wdo trains make a ‘clickety clack’ noise? examine how heat can convert gases,

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 23 4. Screw on the bottle lid and insert Image courtesy of Andrew Brown The Image courtesy of Andres Rueda; image source: Flickr the straw through it into the water, home- making sure that the straw does made thermo meter Old- not touch the base of the bottle. fashioned 5. Seal around the hole in the lid mercury bulb thermo using play dough, thereby fixing meter. The liquid in a bulb the straw in place. The seal must thermometer expands when be completely airtight. heated, causing it to rise up the narrow glass tube. The ther- 6. Place one hand on the upper part mometer in experiment 1 of the bottle. What happens to the relies on the expansion of liquid in the straw, and why? gas, not liquid What happens? The heat from your hand warms the air inside the bottle. The air expands liquids and solids from one to another. • A transparent plastic drinking and pushes on the water, causing it to After each experiment, in the man- straw rise up the straw. ner of true scientists, we question our • A pair of scissors Questions for your pupils results and think about how we could • Food colouring (optional) improve our experimental design. 1. Was it really heat that caused Each of the five experiments relies • Tap water the liquid to rise up the straw, or on simple materials and is suitable for could pressure from your hands be pupils aged 7-11 (although note that Procedure responsible? the reviewer suggested the article is 1. Use a pair of scissors to make a 2. How can we test this suitable for pupils aged 10-13). When hole in the top of the bottle lid, big experimentally? enough for the drinking straw to used together, they could occupy your Answers: the bottle was rigid and, fit through. class for a whole day, but they could assuming you didn’t squeeze, the also be split up and used in separate 2. Fill the bottle halfway with cold liquid rose up the straw due to lessons. Before starting, ask your stu- water. heat, not pressure. You can test this dents to think about what solids, liq- 3. Add a few drops of food colouring by placing your hands close to but uids and gases actually are, in terms and mix. not on the bottle and seeing if the w1 of their appearance and properties . liquid still rises up the straw. of Andrew Brown tesy our e c Changing properties ag Im

1) Make your own thermometer:

Image courtesy of Kdhenrik; image source: Flickr

gases expand when heated

This experiment introduces the idea

that heat makes gases expand. Stu- dents will make their own thermom- Experiment 2: eter based on this principle. watching a knitting Safety note: teachers should per- needle grow form the step involving scissors. See also the general Science in School safety note on page 65.

Materials Per group of pupils: • A rigid plastic bottle with a lid • Play dough or modelling clay, e.g. Plasticine®

24 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Physics Primary edia Com ikim mons : W rce ou s ge 25

a I

m i ; joint x a

r A bridge T n expansion O x s i n P o

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Issue 24 : Autumn 2012 Autumn Issue 24 : u I

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Teaching activities Teaching

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e have seen that solids and gases e have seen that solids l

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expand when heated, but what expand when heated, about liquids? – no exception Answer: liquids are they too expand when heated. I W

expansion cause for bridges or railways? Answer: see the images below. f What pr sion joint, o

rail expan- rail

The heat from the candle causes The heat from

indicated by indicated by s

e t

2. o What happens? As it to expand. the knitting needle it moves over expands lengthways, the sewing needle. The straw and rolls movements of the magnifies the small sewing needle. pupils Questions for your 1.

g a m I Science in School ough ds. oss the mouth Real- oss the mouth of the world problems world Adjust the height of the m in hot weather! caused by expanding solids: caused by rails and bridges expand in hot and rails in Denmark can expand by 4.7 in Denmark can expand by ee end of the knitting needle weather, which can cause them to which weather, Storebæltsbroen (Great Belt Bridge) pile so that the top of the candle the 3 cm from is approximately knitting needle. second bottle. of the one third the drinking straw, way along the straw’s length. The hole should be small enough that the straw does not turn loosely the needle. around Point the straw downwar Place a pile of books between the two bottles. Place the candle on top of the pile of books. Light the candle. What happens to the straw? What causes this? Place the sewing needle (with straw attached) acr of the second bottle, underneath the knitting needle and at right angles to it. Hang a weight (e.g. keys) on the fr Push the cork halfway into one of Push the cork halfway the bottles. of the knitting Push the sharp end of the cork, needle into the side needle is just so that the knitting bottle. above the rim of the the knitting Lay the other end of needle acr Stick the sewing needle thr

A tea light (short candle) A Matches nected by expandable joints; the 18 km nected by buckle or break. Railway engineers leave engineers leave or break. Railway buckle

gaps between sections of rail, which gives gives which gaps between sections of rail, larly, bridges can be built in sections, con- larly, when their wheels run over the gaps. Simi- the run over their wheels when the sections room to expand and also gives the sections room to expand and also gives 7. 10. 8. 4. 5. 9. • • Procedure 1. 6. 2. 3. trains their characteristic ‘clickety clack’ noise clack’ ‘clickety their characteristic trains safety note on A metal knitting needle metal knitting A empty glass bottles (wine Two suitable) bottle are one of the bottles cork to fit A or other object (e.g. set of keys A modelling clay) to weigh down one end of the knitting needle (or other objects to pile of books A support the apparatus) with a cylindrical sewing needle A shaft drinking straw A solids also expand when heated when solids also expand Safety note: because naked flames In the previous experiment, the heat In the previous Bridge) www.scienceinschool.org Denmark’s Denmark’s (Great Belt and sharp objects are used in this used and sharp objects are experiment, it is advisable to perform it as a demonstration. See also the general Science in School Materials • • • • • • • from a pair of hands was sufficient to of hands was sufficient a pair from bottle consider- expand the gas in the expand much Solids, however, ably. in a given increase less than gases for In the following experi- temperature. simple but sensi- ment, we will use a the expansion tive device to observe when heated by a of a knitting needle candle. page 65. 2) Watch a knitting needle grow: grow: a knitting needle Watch 2) Storebæltsbroen

Image courtesy of Kdhenrik; image source: Flickr olm; imag cshark; im ocia; imag erh e so omi age Vél e so Images courtesy of k.landerholm, atomicshark and Vélocia; image source: Flickr nd urc at so of ur .la e of ur sy ce k : y c te : f Fl s e: r F o ic te F u lic y k r l o k s r u ic c r te o k e r c r g u e a o g c m a I e m g Melting I Evaporation a

m I

Freezing Condensation Solid Liquid Gas

Figure 1: This diagram shows the processes responsible for converting the three states of matter from one to another. Changes in state are reversible

Changing states 2856 °C) and the liquid boils and turns boil water. But in theory at least, all So far, students have seen what hap- into a gas. substances can exist in the three states pens when we heat solids and gases: Of course, this is a rather extreme of matter. they expand. You have also told your example; most of us will never experi- In the following experiments, we students that liquids do the same. But ence gold in its gaseous form. But will look at what happens when we what happens when we heat sub- everyone in the class will be familiar turn liquid water to a gas – and back stances even further (figure 1)? Ask with water moving through the three again. your students to think about a bar states of matter: turning from solid of gold; it is solid at room tempera- ice to liquid water (0 °C), then to its 3) Liquid to gas: evaporation on ture, at 100 °C, and even at 500 °C. gaseous form, water vapour (100 °C). your finger But what happens when we raise the So as well as expanding them, heat Even before a liquid boils, some temperature even higher, to 1064 °C? can also cause substances to change of it may start to turn into gas – ask At this temperature, something amaz- state. Different substances require your students to think of the wisps ing happens: the solid gold becomes a different amounts of heat to do this: of steam that come off a pan of water liquid! Heat the liquid further still (to it takes more heat to boil gold than to long before it boils. In this experiment, students will see that that even

mage s our fingertips generate enough heat OM; i ource GC : W H iki f P m to make small amounts of water turn o ed sy ia e C rt u o from a liquid to a gas. We call this o m Liquid c m e o g n process evaporation. a s gold being m I poured into a cast to make a Materials gold bar • A cup of water

Procedure Im a g e c This experiment is best done out- o u r t e doors or somewhere where there is a s y

o f draft, such as near an open window. T h The e

P 1. Dip your index finger in the water,

world’s largest z

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bar of gold is in a r

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museum in Toi, Japan. a

It weighs 250 kg and at s

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the time of writing is c

worth about US$12 F The water evaporates from your li

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million r finger, leaving it dry. Your finger also feels cold. This is because the heat from your body is transferred to the liquid water and carried away in water vapour.

26 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Im a ge c ou r te sy o f A n d re w B Image courtesy of bratboy76; image source: Flickr r o w Teaching activities n

rown ew B ndr f A y o es rt ou c e g a Im Water will evaporate from your finger

An elephant squirting water onto its back

Questions for your pupils 1. In this experiment we heated liquid water, but what happens Physics Procedure Questions for your pupils when we heat a solid? Think about 1. In this experiment we cooled a gas what happens when you heat 1. Run the cloth under a tap to make (water vapour), but what happens butter. it wet and then squeeze it to when we cool a liquid? Think Answer: solids melt when heated. remove the excess water. about how you make ice cubes. 2. How could we improve our 2. Place the cloth inside a plastic Answer: when cooled, liquids experiment? bag. Trap some air inside the bag freeze and become solid. Answer: what if your finger felt and seal it. 2. How could we modify our cold not because of evaporation, 3. Leave the bag in a warm place, experiment to make the water but because the water was cold? To such as on a radiator or in direct droplets form faster? test this idea, we could use water sunlight, for one hour. What do Answer: making the surface of the at body temperature (37 °C). Try it you see? – you should get the same result. bag colder, for example by placing ice cubes next to it, will make 3. Using what you have learned, What happens? can you explain why elephants condensation occur faster.

Water droplets form on the inside Primary sometimes squirt water onto their 3. Which causes fog: evaporation or surface of the bag. backs? condensation? How? Water evaporates from the Answer: elephants do this to Answer: fog forms when water wet cloth so that the air inside the bag cool themselves down, by taking vapour cools and condenses into a contains lots of water vapour. The in- advantage of the cooling power of cloud of small water droplets near side surface of the bag is cool enough evaporation. the ground (like a cloud but lower to change the water vapour back into down). 4) Gas to liquid: condensation liquid water. in a bag Students have seen that heating a liquid can turn it into a gas (evapora- wn ro tion), but this is a reversible process: B ew dr n cooling a gas sufficiently turns it into A f o Condensation sy a liquid, in a process called condensa- e rt u in a plastic o tion. In the following experiment, stu- c e g bag a dents will investigate condensation. m I Materials • A transparent plastic bag • An elastic band • A small cloth • Water

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 27 Acknowledgement Resources The instructions on how to make a Watch a video of a simple experi- thermometer were adapted from the ment showing that gases expand Erland Andersen is a former California Energy Commission’s when heated, involving nothing primary-school teacher from Den- Energy Quest website. For this more than a refrigerated drink mark. He now provides training w2 and other science projects, see: and a coin. www.metacafe.com/ courses for science teachers . www.energyquest.ca.gov/projects watch/333171/jumping_coin or Erland developed the activities in use the shorter link: http://tinyurl. this article as part of a ‘small energy w3 Web references com/slgexp1 driving licence’ . Pupils earn their licence by performing energy-related w1 – The BBC Bitesize website fea- Watch a video showing solids ex- tures concise, high-quality teaching experiments in small groups. Erland panding when heated and gases encourages the pupils to explain and resources for students. It includes an contracting when cooled (involves excellent section on the properties of question their results, and to use fire, liquid nitrogen and a balloon). what they have learned to explain solids, liquids and gases. See: www. http://youtu.be/tPJLFDekxZA bbc.co.uk/schools/ks2bitesize/ real-world phenomena. science/materials or use the shorter If you enjoyed reading this article, Andrew Brown is a molecular link:/http://tinyurl.com/ceyt6te you can browse the full collec- and cellular biology graduate of the tion of Science in School articles for University of Bath, UK. He currently w2 – To find out more about one primary-school teachers. See: works for Science in School, based of the authors, visit Erland www.scienceinschool.org/primary at the European Molecular Biology Andersen’s website (in Danish): Image courtesy of archer10 (Dennis) OFF; image source: Flickr Laboratory in Heidelberg, Germany. www.naturfagskurser.dk w3 – The small energy driving licence certificate and teacher’s handbook (both in Danish) can be downloaded

from the website of the Danish Sable Island, off Electricity Association (Dansk the coast of Nova Scotia, El-Forbund; www.evu.dk) or via Canada, is known as the ‘grave- the direct link: http://tinyurl.com/ yard of the Atlantic’. The island To learn how to energylicence is 36 km long and is located where use this code, see page 65. warm, moist air from the Gulf Stream is cooled by air from the Arctic Ocean, causing frequent heavy fogs. This makes it is a dangerous place for ships: at least 350 vessels have been wrecked there

28 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Image courtesy of stock photos for free.com TeachingScience activities topics Biology Physics Physics

Physics Seeing is believing: General science Biology Optics 3D illusions Ages 14-19* The use of 3D illusions in the visual media is becom- To make the two-dimensional images that ing increasingly popular. But how is it that we see we see in print and on screen appear more a 2D picture in 3D? And how can we create our own real, we can hijack our brains to create the 3D illusions? These ques- illusion of a third dimension, depth. These tions and many more are answered in this novel arti- activities explore the physics that make this Image courtesy of DTR; images source: Wikimedia Commons cle. The great thing is that it does not just give explana- possible. tions, but also provides a number of activities to help the students understand what is going on. It is very By Andrew Brown useful as a way of linking theory to real-life applications. ook around you. How many Suitable for teachers of dimensions can you see? As a brains process those 2D images into physics (optics) and general three-dimensional being living something that appears to have not science, this article would inL a three-dimensional world, surely only height and width but also depth also be good background you see three dimensions: height, – three dimensions. Thus, the brain reading for biology (vision) width and depth? Not so. In fact uses 2D images from the eyes to create and art teachers. you see only two dimensions. This an illusion of 3D. Paul Xuereb, Malta is because what we see is merely 2D The four activities in this article, *Note that the activities were images, even of 3D objects, projected suitable for 11- to 19-year-old physics used by the IOP for students onto the backs of our eyes. What students, investigate how we can

REVIEW aged 11-19 we perceive is entirely different: our hijack the workings of the brain to

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 29 make an object that is genuinely 2D These anaglyphs (see activity 2) were created from to begin with – such as a drawing, images taken with a scanning electron microscope. painting or movie – appear 3D. Use your red / green glasses to view them.

Activities 1, 2 and 3 take about 20 Image courtesy of Syngenta minutes each, and activity 4 takes about 30 minutes. The materials required are inexpensive but will require sourcing in advance. Although this article mainly covers physics topics, it could also be adapted for use in biology lessons because it deals with vision and the brain.

Adding another dimension First, how does the brain allow us to perceive truly 3D objects in three dimensions? We use this ability every time we do something as simple as pouring a drink. Cover one eye, keep your head The surface of the fruit of the still and your eyes level with the top cleavers plant is covered in tiny of the glass, then try to pour the water hooked hairs, which cling to animals to enable seed dispersal. into the glass. It’s difficult. Now open both eyes and try again. This time, your brain receives two slightly different images of the same objects, which it uses to perceive depth. As a result, you should be able to pour the water accurately into the glass. We can exploit this ability of the brain in order to enhance the realism of a 2D picture. We do this Image courtesy of Syngenta by presenting each of our eyes with a slightly different image, mimicking what happens when we look at a 3D object. The brain combines these two images, convincing us that there is depth in what is actually a 2D picture. Three strategies are used to create these 3D illusions. The first strategy Spores of a pathogenic (covered in activity 1) directs a differ- fungus (wheat yellow ent image into each eye using refrac- rust) erupting through the surface of a wheat leaf. tion, whereas the other two strategies (activities 2 and 3) use different types of special glasses. In activity 4, students use what they have learned to depth. If so, they’ve already encoun- Procedure make their own 3D image. tered 3D lenticular pictures. In the 1. Cover your left eye and look at the Activity 1: 3D lenticular images following activity we will investigate picture. Then cover your right eye Your students may have seen how they work. instead and look again. designs on postcards, DVD covers or Materials 2. Look at the picture with both eyes. the cards you find in cereal packets Per student or pair of students: What do you notice? that seem to have an amazing sense of • A 3D lenticular picture

30 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Teaching activities

What happens? Figure 1: 3D lenticular pictures: how they are made and how they work When you view the picture with Biology both eyes it looks 3D, but when you view it with only one eye it looks 2D.

How does it work? Image courtesy of Lenstar.org a The simplest 3D lenticular pictures are created from two separate images, which are offset from one another laterally. Let’s take as an example a composite picture made of picture A b and picture B. Both pictures are cut into vertical strips and reassembled alternately into what is called an c interlaced image (figure 1a), making the order of strips: A-B-A-B-A…. The interlaced image is printed onto paper Physics and overlain by a sheet of lenticular plastic, which consists of a series of long, thin lenses (figure 1b). The lenses are aligned with the underlying strips in such a way that light reflected off strips of A will be sent in one direction, to the left eye, and light reflected from strips of B is sent in another direction, to the right eye (figure 1c). a) Two separate images, A and B, are cut into strips and then reassembled alternately, to form an interlaced image. The images are also offset from one In our experiment, your brain another laterally. combines pictures A and B of the b) The interlaced image is printed onto paper and overlain by a sheet of lenticular lenticular picture to give an illusion plastic consisting of plastic lenses. of depth. The illusion works because c) The lenses send light reflected from strips of A to one eye and from strips of B the two pictures are offset from one to the other eye. The brain combines the images to create the illusion of depth another, so the brain is combining two different images – just as it does when you look at a 3D object with two eyes. 3D movies took advantage of colour There is no such illusion of depth to create the illusion of 3D. Watch- when you look through a single eye: ers wore red / green glasses to view either your left eye sees only picture A a projected picture composed of two or your right eye sees only picture B. offset pictures: one red and one green. Such pictures, called anaglyphs, are Red / green glasses Activity 2: anaglyphs still used widely today in printed ma- Whereas lenticular 3D pictures

Image courtesy of DTR; images source: Wikimedia Commons terials. In the following activity, your work when viewed with the naked students will learn how anaglyphs eye, other ways of creating the illusion work. of depth require special glasses. Early Materials

Per pair of students: Image courtesy of Andrew Brown • A pair of red / green glasses Procedure 1. Wear the red / green glasses with the red filter over your left eye and the green filter over your right eye 2. Look at one of the anaglyphs on page 30.

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 31 Image courtesy of DTR; images source: Wikimedia Commons What happens? How does it work? The anaglyph appears to have To understand your observations, depth: it looks 3D. and how modern 3D movies work, we How does it work? need to remember that light travels in waves. We can influence the orien- We can filter light based on its tation of the waves’ oscillations by colour (wavelength). The red filter in passing the light through a circular your glasses absorbs all wavelengths polarising filter, which makes the of light apart from red, whereas the oscillations travel in spirals (figure 2). green filter absorbs all wavelengths The lenses in your 3D glasses contain apart from green. circular polarising filters: one polar- To make the anaglyph, each of the two component pictures was taken from a slightly different position Figure 2: The way light travels in waves can be affected by polarising filters before being coloured: one in red Images courtesy of Bob Mellish (top) and Dave3457 (bottom); image source: Wikimedia Commons and one in green. When you look at Un-polarised light: normally, the peaks and troughs of a wave of light point in the anaglyph with your red / green random orientations about the axis of its movement glasses on, your left eye receives the red image and your right eye, the green image. The illusion of depth is created when your brain combines the two offset images. Activity 3: 3D polarising glasses Most modern 3D movies use polarising glasses to achieve the illusion of depth. The following activity investigates how these glasses work. Materials Per pair of students: Axis of movement • Two pairs of 3D polaroid glasses, such as those made by RealD™

Procedure Circularly polarised light: circular polarising filters cause the wave’s oscilla- In pairs: tions to rotate about its axis of movement, in either a clockwise or an anti- 1. Wear your glasses and look at your clockwise direction, depending on what kind of filter is used. The wave shown partner. here is polarised in a clockwise direction 2. Cover the left lens and look at your partner, who should have both lenses uncovered. What do you see? 3. Cover the right lens and look again. What has changed?

What happens? When you look at your partner with both of your lenses uncovered, your partner’s lenses look transparent. When you cover one of your lenses, one of your partner’s lenses appears to darken. If you cover your other lens, your partner’s other lens appears to darken.

32 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Teaching activities

Image courtesy of stock photos for free.com Image courtesy of libraryman; image source: Flickr Biology

ises light in a clockwise direction and Figure 3: The darkening lens experiment. The blue lines indicate light passing through Physics the other in an anticlockwise direc- your partner’s clockwise (CW) lens, while the red line indicates light passing through your partner’s anticlockwise (ACW) lens. tionw1. Let’s think about what happens when you look at your partner with A CW ACW A) Your partner’s lenses ap- both of your lenses uncovered (figure pear transparent when both 3A). Your partner’s lenses appear your clockwise (CW) and anticlockwise (ACW) lenses transparent, because you are able to are uncovered. CW polarised see the light that has passed through light (blue) coming from your them: clockwise polarised light from partner’s glasses reaches one your partner’s clockwise polarising of your eyes, while ACW po- lens reaches one of your eyes, while larised light (red) from your anticlockwise polarised light from ACW CW partner’s glasses reaches your your partner’s anticlockwise polaris- other eye ing lens reaches your other eye. Now think about what happens B CW ACW when you cover your clockwise polarising lens (figure 3B). Your partner’s B) When your CW lens is clockwise polarising lens appears covered, your partner’s CW lens appears darker. darker, because you no longer receive This is because you are no the light that has passed though it. longer able to see the light Why not? Because your anticlockwise that passed through your polarising lens (the only lens through partner’s CW polarising lens which you can now see) blocks the ACW CW clockwise polarised light. When you cover your other lens (figure 3C), the situation is reversed and your part- C CW ACW ner’s other lens appears darker. C) When your ACW lens is The 3D movies for which your covered, your partner’s glasses were designed are filmed us- ACW lens appears darker ing two cameras mounted so that the distance between the cameras’ lenses is roughly equal to that between the average pair of human eyes. During the movie, the two moving pictures ACW CW are circularly polarised in oppo- site directions and projected onto a screen. Your 3D glasses ensure your Image courtesy of Nicola Graf

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 33 Image courtesy of Nicola Graf left eye receives one image, and your right eye the other. The two moving pictures are displayed alternately at an imperceptibly fast rate of 144 times per second. The brain combines the images it receives from both eyes to Figure 4: Mak- create the illusion of depth. ing an anaglyph: photo 2 should be Activity 4: making your own taken from a posi- 3D image tion slightly to the right of photo 1. Once your students have under- The two images stood the principles of 3D imaging, are made into an they can make their own anaglyph Photo 1 Photo 2 anaglyph using using a digital camera and a computer 6 cm your chosen piece (figure 4). of software

Materials • A digital camera • A tripod or other type of support for the camera (e.g. a pile of books) • A pair of red / green glasses Software • A piece of software that can make an anaglyph, such as Anaglyph Workshopw2. Acknowledgements Web references Procedure The activities in this article were w1 – Circularly polarising 3D glasses 1. Choose a stationary subject. devised by Alison Alexander, Cerian are in fact slightly more complicated 2. Take a photo. Angharard, Frances Green and Ruth than described in this article, as they 3. Move to the right by about 6 cm Wiltsher, who are all physics-teacher contain both a linearly and a circu- (about the distance between our network co-ordinators for the UK’s larly polarising filter. Read a more eyes), ensuring that the camera w3 Institute of Physics (IOP) . These and detailed explanation of how the remains at the same level. Take a other activities were originally part of glasses work: www.3dtvtechnology. second photo. a package of activities called ‘Lights, org.uk/polarization 4. Follow the instructions of your cameras, images’ that was used for w2 – The Anaglyph workshop chosen software to colour and a workshop for the IOP’s teacher software for Windows or Mac is superimpose the two photographs. network. freely available to download. See: You now have an anaglyph. The worksheets for all of the ‘Lights, www.tabberer.com/sandyknoll/ 5. Look at your anaglyph through cameras, images’ activities can be more/3dmaker/anaglyph-software. your red / green glasses, either downloaded from the Talk Physics w2 html, or use the shorter link: http:// website . on a computer screen or a print- Image courtesy of DTR; images source: Wikimedia Commons tinyurl.com/anaglyphmaker out. You may need to repeat the procedure a few times, adjusting w3 – The UK’s Institute of Physics the distance you move before (IOP) teacher network provides taking the second photo, to refine support for physics teachers across the 3D effect. Great Britain and Ireland. See: Note: if you have a smart phone, www.iop.org or use the direct you can simplify the procedure by link: http://tinyurl.com/ using an app (e.g. 3D Photo Maker) iopnetwork to make your anaglyph directly, us- The IOP website has an extensive ing images taken with your phone’s collection of resources for physics camera. teachers. See: www.iop.org/ education

34 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Teaching activities

The complete set of worksheets for Biology the ‘Lights, cameras, images’ activi- Andrew Brown is a molecular ties are available on the Talk Physics and cellular biology graduate of the website (www.talkphysics.org), a University of Bath, UK. He currently resource from the IOP for teachers works for Science in School, based of physics and their supporters. at the European Molecular Biology Search for ‘lights’ or use the tinyurl: Laboratory in Heidelberg, Germany. http://tinyurl.com/lcmworksheet. You need to register to use the website, but registration is free. Resources The highly praised animation ‘Imag- ining the Tenth Dimension’ includes an explanation of how to imagine the higher dimensions. See: http:// tenthdimension.com/medialinks. Physics php If you enjoyed reading this article, you can browse the full collection of Sci- ence in School teaching activities. See: To learn how to use this code, see page 65. www.scienceinschool.org/teaching Image courtesy of Manuel Martín; image source: Wikimedia Commons

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 35 Images courtesy of the European Commission

Always turn off the lights when you leave a room, and use energy-saving

The European light bulbs. They not only use less school challenge energy per hour, but last up to 10 times longer than incandescent bulbs

In a class of their own: lessons in energy and education from European schools

f we don’t protect our environment, we won’t have “ one,” says Carolina, 13, from Is the energy you Portugal.I are using from a How far would you be willing to go renewable source? to raise awareness amongst staff and students at your school of the need for sustainable energy? You could get creative with the curricula. As a topic, energy efficiency tion on the environment. Religious efficiency in schools. The calibre of the lends itself to a host of disciplines, education might tackle the ethics of entries certainly did not disappoint. from easier fits like science, technol- sustainability. You could engage with Among the exceptional projects ogy, engineering and mathematics children’s creativity by producing identified by the campaign, there (STEM subjects) right through to the journals, reports or works of art about are several that deserve particular humanities and arts: there are many sustainability. attention due to their originality and approaches that teachers can be But would you be willing to lobby success. encouraged to take. Biology lessons your local mayor for support? Or As diverse and inventive as the could look at the effects of pollu- take to the streets where you live children and teachers themselves, the with drums and banners or sandwich winning projects share some key fea- boards? Or travel to another conti- tures and values. A common approach nent to showcase sustainable-energy Image courtesy of the European Commission was to give the children a certain What’s your carbon business models that you and your degree of freedom and responsibility, footprint? students have created together? which encouraged fuller involvement The challenge to get creative about sustainability was issued this year by and enthusiasm, as well as securing the U4energy competitionw1, an initia- real learning outcomes. Also, in all the tive funded through the Intelligent projects, engagement with local com- Energy Europe programme of the Eu- munities – from parents and families ropean Union. A pan-European hunt to friends, local businesses, and in was launched to recognise and reward some cases, the local authorities – has exceptional efforts to promote energy extended reach and impact.

36 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Advertorial Image courtesy of the Grouping of Schools of the City of Castelo Branco, Portugal

Save energy – main concern Portugal’s ‘Environ- “If you want to pass on a message to mentally friendly the adults, first pass it on to the young school’ project ones,” says Sister Claudia Zammit, spilled onto the streets with ‘walk- headmistress of St Francis Primary ing and biking to School in Malta. school’ days Winner of the category for ‘best energy efficiency measures’, the St Francis ‘Save energy – main concern’ project has engaged youngsters from ages 5 to 11 in conservation with a raft of activities. From rotating teams of ‘auditors’ and ‘detectors’ monitoring Image courtesy of St Francis Primary, Malta energy waste, to poetry, song and craft workshops, and even appearances on Learning to save national radio and TV, pupils there energy at St Francis have embraced the concept of saving Primary School in energy with enormous enthusiasm. Malta “I was even told by a little girl aged

7 to switch off my unused computer,” Images courtesy of the European Commission reports Sister Claudia. A substantial drop of 20 % in energy consumption at the school was recorded last year, and effects logged by pupils at home attest to the reach of this project: “At home, we now use 2-3 units per day. My family is very happy because it used to be 5-10 units,” reported Nigel, aged 10. role reversal, with pupils nagging the teachers about conservation. Environmentally friendly school Manuela is the driving force behind ‘walking and biking to school’ days, Manuela Costa from Portugal also Portugal’s ‘Environmentally friendly and a range of inventive awareness- reports that pupils aged 3-15 at the school’ project, an initiative that has building campaigns. One of the most Grouping of Schools of the City of so far touched the lives of 1000 stu- enjoyable elements, for staff and Castelo Branco take the environment dents, staff, parents and members of pupils, was the involvement of the so seriously that she has noticed a the local community. school percussion band, who quite The project kicked off in 2010 literally took to the streets of Castelo when solar panels were installed Branco with banners and flyers to beat European right across the school. Today, water, the drum for renewable energy. electricity and waste ‘brigades’, made Parents have had a key role too, and Schoolnet up of mixed groups of children from many have come in to talk about en- European Schoolnetw2 is a network different years, patrol the school and ergy consumption in their workplaces. of 30 ministries of education in Eu- report back to staff on their findings. And such is the zeal of these pupils rope and beyond. U4energy is the All the pupils in the school have been that mums and dads have reported first pan-European competition on involved in the project, and energy being lobbied at home by children as energy education organised by the consumption across the school’s young as three. European Commission and pow- buildings dropped by 15 % as a result. For Manuela, dedication like this ered by European Schoolnet. Enthusiasm like this was hard to begins in the classroom: “The key is to contain within the confines of the teach children from a very young age school itself, which is why activities about renewable energy and the need spilled over into the community with to use it rationally.”

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 37 Innovation starts with you

Top ten ways to reduce energy Image courtesy of the European Commission Energy work bike Almerindo Capuani of the Alessan- consumption drini Marino Institute in Teramo, Italy, 1. Switch off electronic devices took a novel approach to mobilising when you are not using students (aged 17-18) to think about them. sustainability, energy sources and 2. Turn down the thermostat by development. one degree and save 300 kg The ‘Energy work bike’ project is an of CO2 each year. undertaking so inventive, so dynamic 3. Switch off lights when not in and so multifaceted that it defies sim- use. ple definition. Part electrical engineer- 4. Insulate walls, roof and ing, part technology, part design and we began working on this. Inside the floors well. part philanthropy, this extraordinary classroom we focused on integrating 5. Use reflective panels behind scheme has seen students produce different subjects and disciplines from heaters to reflect the warmth four prototypes of energy-producing automatic electric systems to engi- into the living spaces. bikes that can charge a mobile phone, neering,” he says. 6. When cooking, cover pots sharpen work tools, power a laptop, “At the same time, we wanted to and pans with lids. or harness the Sun’s rays and convert encourage students to address real-life them to electricity. 7. Turn the tap off while soap- issues that affect us as citizens: urban ing hands or brushing teeth. Two patents and a fully fledged pollution, sustainability and world business plan later, the whizz-kids 8. Invest in energy-efficient poverty. The students were also keen Collaborate withfrom Teramo industryhave travelled to the light bulbs. to play their part in making a differ- Butembo Mission in the Democratic 9. Position your radiators with ence: the energy produced is limited, Join the communityRepublic of Congo, where they met care. and does not solve any problems in with monks and youngsters eager to 10. Take short showers. Italy, but in Butembo and in develop- find out how to replicate the bikes for ing countries it can become part of a inGenious is the largest energyEuropean and potentially platform for employ- dedicated to solution to many needs.” ment. Web references helping science teachersFor communicate Almerindo, the benefits the and valuehim andand his colleaguescareer were quite potential of science, technology,rewards of this projectengineering address a wide andclear, maths if ambitious, studies. from the start. w1 – More information on the projects range of pedagogical, environmental “We wanted to address a range of as well as ideas and inspiration and societal objectives: goals that for diverse and complex elements when for teachers are available on the Industry and school collaboration is at the heart of inGenious. U4energy website: www.u4energy.eu w2 – More information on educational Enter our CommunityImage courtesy of the Institute Higher Education Alessandrini-Marino of Teramo, Italy to: projects for teachers across Monks from Europe is available on the Butembo learning European Schoolnet website. • learn about innovative education approaches from the ‘Energy work bike’ team www.europeanschoolnet.org • collaborate with key businesses to inform pupils abouthow careers the equip- Resources ment works In June 2012, Euronews reported on • access and use a repository of best industry–school education activitiesthe successes of U4energy in Malta: www.euronews.com/2012/06/21/ Join inGenious at: green-is-the-colour http://ingenious-science.eu/web/teachers/home www.ingenious-science.eu

To learn how to use U4energy is an initiative this code, see page 65. InGenious is supported by the European Union’s Framework Programme for Research and Developmentfunded (FP7) through – project the Intelligent ECB: European Coordinating Body in Maths, Science and Technology (Grant agreement Nº 266622). The content of this advertisement is the sole responsibility of the ConsortiumEnergy Europe Members Programme and it ofdoes not represent the opinion of the European Union and the European Union is not responsible or liable for any use that might be made of information contained herein.the European Union 38 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org

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www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 39 Image courtesy of SixRevisions; image source: Flickr

Indigo: recreating Image courtesy of Jeff Dahl; image source: Wikimedia Commons

Indigo being extracted Pharaoh’s dye from plant leaves What links your jeans, sea snails, woad plants and the Egyptian royal family? It’s the dye, indigo. Learn about its fascinating history and how you can extract it at school.

Image courtesy of gitane; image source: Wikimedia Commons

By Gianluca Farusi (see box on page 46), we even know All about indigo the dyeing methods used by ancient Indigo is an organic compound that n ancient Egypt, only one boat had civilisations. This activity allows your is found in three differently coloured a purple-dyed sail. It belonged students to follow in the footsteps of forms – indigo itself, which is blue; to the Pharaoh and was a vibrant these early chemists, extracting indigo purple mono-bromoindigo; and red- Iand powerful sign to other Nile users from the leaves of the woad plant. purple di-bromoindigo (figure 1). Nat- that they should move aside to let the Using basic lab equipment, second- urally derived dyes can contain just royal boat pass. ary students of all ages could carry one of these pigments or a mixture of Even today, deep blue, purple and out this extraction in one or two prac- two or three in variable proportions, crimson are traditionally associated tical sessions. Younger students (ages leading to a range of colours from red with royalty, luxury and wealth. This 11-15) could simply do the extraction to blue (Cooksey, 2001). The intensity is because they are difficult and ex- without going into much detail about of the colour is also influenced by the pensive colours to achieve using natu- the chemical reaction [although note way it is processed, such as whether ral dyes. Until the advent of synthetic that the reviewer suggested the activ- the dyed cloth is dried in the light or dyes 100 years ago, natural dyes (from ity was suitable for students aged shade. plant, animal or mineral sources) were 14+]. More advanced organic chemis- In ancient Egyptian times, the best the only way to colour fabrics. try students (ages 16+) could inves- quality indigo was extracted from The vivid purple of the Pharaoh’s tigate the compounds and reactions Murex sea snails, which were once sail was achieved using indigo – a more thoroughly. The experiment is common in the coastal waters of the natural dye that can be extracted from also relevant to the use of science in eastern Mediterranean. Archaeologi- certain plants and animals. Thanks industry and could be used as part of cal evidence from Crete suggests that to Roman naturalist Pliny the Elder a project on this topic. indigo extraction from Murex snails

40 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Image courtesy of dudchik / iStockphoto Science education projects Chemistry Image courtesy of Jeff Dahl; image source: Wikimedia Commons

Modern painting of an Egyp- tian royal boat, with a furled Chemistry imperial purple sail. Note that Biology ‘purple’ is not always what we Organic chemistry would expect today Botany Ages 14-19* In this and several other Sci- ence in School articles, Gi- anluca Farusi successfully blends ancient history and chemistry in an unusual mixture – in this case, an

Images courtesy of Gianluca Farusi innovative and simple prac- had begun by 2000 BC. By 1000 BC the tical activity to isolate the Phoenicians, a civilisation centred in dye indigo from the leaves what is now Lebanon, were exploit- of the woad plant (Isatis ing this valuable dye. Their entire tinctoria). In my experi- economy was based on trading Tyrian ence, practical activities in- purple, a violet-purple indigo dye volving intense colours are derived from the snail Murex brandaris an effective way to attract (now known as Bolinus brandaris). the students’ attention. They were so famed for it that the The additional activities name Phoenician is derived from the and supplemental ques- Greek word ‘phoinísso’, meaning ‘to tions suggested in the arti- make red’. cle should help the students Murex-derived indigo was so expen- gain yet more practical sive because 12 000 snails yield just skills and also stimulate in- 1.4 g Tyrian purple – enough to dye a triguing questions, as well handkerchief! The compounds used as offering sound answers. to make the dyestuff are secreted by Vladimir Petruševski, the snail’s hypobranchial gland, found Republic of Macedonia between the bowels and the branchial *Note that the author recom- organ. The snails appear to produce Figure 1: Structures of indigo (top), mended the activity for 11- to

these indigo precursors as a defence mono-bromoindigo (middle) and REVIEW 19-year-olds response and for their antimicrobial di-bromoindigo (bottom)

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 41 A O B OH

Indoxyl (A) and Image courtesy of H Zell; image source: Wikimedia Commons indolin-3-one (B) are tautomers – isomers that exist together in N N equilibrium H H

properties. The fresh secretions are The Phoenicians perfected this colourless, but darken when exposed process over hundreds of years and to air. According to Pliny the Elder, discovered that by varying the species the dye was extracted by crushing of snail, extraction methods and pro- Shell of the snail Murex brandaris, the snails, leaving them to putrefy for cessing, they could produce a range the secretions of which were first three days in alkaline salt water, and of colours from red to purple to blue used to make indigo in 2000 BC then boiling them for up to ten days – (table 1). imagine the smell!

Species Appearance Dye precursors Dye name Colour Chemical found in the or- composition ganism of dye source: Wikimedia Commons source: Wikimedia Image courtesy of H Zell; image Bolinus 6-bromoindoxyl Tyrian purple / Red-purple Mainly brandaris imperial purple di-bromoindigo (formerly / argaman Murex brandaris)

source: Wikimedia Commons source: Wikimedia Image courtesy of Dezidor; image Hexaplex Indoxyl and Royal blue / Blue-purple Mixture of indigo, trunculus 6-bromoindoxyl tekhelet mono- and (formerly di-bromoindigo Murex trunculus)

Image courtesy of Kurt Stüber; image source: Indigofera Wikipedia Commons Indican Indigo Blue Indigo tinctoria (true indigo)

Image courtesy of Pethan; image source: Isatis tinctoria Wikipedia Commons Isatan B Indigo Blue Indigo (woad)

Table 1: Natural sources of indigo

42 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Image courtesy of PKM; image source: Wikimedia Commons Science education projects

Indigo-dyed linen from 1873 Chemistry

A B Images courtesy of Gianluca Farusi

Lower-quality indigo can also be Figure 2: Indigo precursors found in plants: indican (indoxyl-β-D-glucoside, found in extracted from certain plants, and true indigo; A) and isatan B (indoxyl 3-ketogluconate, from woad; B) this technique actually pre-dates the Phoenicians’ snail-derived dye. In Images courtesy of Gianluca Farusi India, methods of extracting indigo HO OH from the ‘true indigo’ shrub Indigo- fera tinctoria were known before 2000 HO OH O A: Boiling the leaves to BC. In Europe, the dye was extracted extract the water-soluble from woad (Isatis tinctoria). Although Boiling O isatan B these two plants contain different O precursors, indican in true indigo and isatan B in woad (table 1 and N H figure 2), they both ultimately yield the same dye – indigo. The production of indigo from HO OH woad takes place in three main B: Adding alkali (ammo- O stages: HO OH nia) to hydrolyse the O molecule, removing the Ammonia 1. Boiling the leaves to extract the O carbohydrate group to water-soluble isatan B (figure 3A; O leave indolin-3-one (or N steps 1-6 in the activity below). H its tautomer, indoxyl) 2. Adding alkali (ammonia) to N H hydrolyse the molecule, removing the carbohydrate group to leave O O O indolin-3-one or its tautomer, indoxyl (figure 3B; step 7 in the H C: Exposing the extract to activity below). N N N H H H the air, leading to the 3. Exposing the extract to the air, O oxidation and coupling H leading to the oxidation and N of two indolin-3-one coupling of two indolin-3-one OO molecules to form the molecules to form the blue- N blue-coloured indigo H coloured indigo (figure 3C; O N N dyeing the wool and obtaining H H indigo powder in the activity Figure 3: Chemical conversion of isatan B to indigo below).

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 43 Student activity: extracting indigo from woad leaves

Materials Image courtesy of naturaldyer; image source: Flickr For each group of students: • Fresh woad (Isatis tinctoria) leaves (enough to fill a 1 l beaker) Woad seeds are easily obtainable from garden centres, and in some countries woad is a very common plant. • 20 wt% ammonia solution • Three 1 l beakers • Distilled water • Octanoic acid (optional) • Bunsen burner and tripod • Stirring rod Powdered indigo against a background of woad from which it was extracted • Sieve or strainer • Measuring cylinders and/or 10 ml pipettes water, stirring both the extract in To use the indigo powder as a dye, the beaker and the water in the • Heatproof gloves it needs to be dissolved in water and tray. You now have a solution mixed with a reducing agent, such • Funnel and filter paper containing, among lots of other as sodium hydrosulphite (Na S O ). • Knife for cutting the leaves 2 2 4 things, isatan B, which is an When the dyed material (e.g. wool) is (optional) unstable glycoside of indoxyl. exposed to air, it will turn blue. • Wool for dying (optional) 7. When cool, measure the volume Safety notes: I used a ball of white knitting wool, of your extract and add ammonia Remember that indigo and many and some rough grey-white sheep’s equivalent to 1 % of that volume, of its precursors are dyes, so take care fleece. e.g. for 1 l extract, add 10 ml not to spill them on clothes or skin. ammonia; for 100 ml extract, add 1 Procedure When handling concentrated ammo- ml ammonia. The solution should 1. Fill a beaker with woad leaves. nia solution, as well as indigo and its immediately change from brown Remove the leaves from the beaker precursors, wear gloves and chemical to brown-yellow then green. You and cut or tear into small pieces. splash glasses, and use a fume hood. now have a solution containing, 2. Fill the beaker two-thirds full with among lots of other things, Questions for discussion distilled water and bring to the indoxyl. boil over a Bunsen burner. • Why do we boil the leaves? What is To dye wool 3. Add a few torn leaves to the happening? boiling water, stir and continue 1. Wet the wool and place in the • What happens when the ammonia heating. When the water has extract for 10 minutes. Remove is added? returned to the boil, add a few and leave to air dry. • When you dye the wool, why does more leaves. Continue adding To obtain indigo powder the blue colour appear as the wool leaves and heating until all the 1. Aerate the extract by pouring dries? woad has been added. the solution from one beaker to • When you produce the powder, 4. When all the leaves have been another for 10 minutes. what is happening when the added, continue boiling for 1 2. Optional: if too much foam solution is poured from beaker minute. develops during aeration, add to beaker? Why does the indigo 5. Strain all the liquid from the boiled some octanoic acid, drop by drop. precipitate? leaves into a clean beaker. This acts as a surfactant. • Can you find out how indigo is 6. Cool the extract to room 3. Filter the extract through ordinary produced industrially today? What temperature by floating the beaker filter paper to obtain the indigo are its major uses? in a shallow tray full of cold powder.

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Image courtesy of Marcel Douwe Dekker; image source: Flickr Chemistry

Made in the 11th century, the Bayeux Tapestry celebrates the tion to produce the ten colours found in the 70 m embroidery: Norman conquest of England; a turning point in English history. woad (blues and greens), madder (Rubia tinctorum; reds) and Shown here is the Battle of Hastings at which William, Duke weld (Reseda luteola; yellows and dark green). To achieve the of Normandy, defeated Harold, Earl of Wessex, on 14 October desired colour intensity, the wool was successively soaked and 1066. Three plant-based dyes were used alone or in combina- air-dried.

Extension activities

You could also ask your students to further investigate b) Grow plants with and without added nitrogen the chemistry of indigo and other dyes with some of fertiliser. Aim for 2-4 g nitrogen per m2 of soil the following activities. (you will need to calculate the amount of fertiliser Calculating the yield of indigo that gives this amount of nitrogen). Does adding nitrogen fertiliser increase the amount of indigo Weigh the leaves before the extraction and the dried indigo powder. Calculate the percentage yield of produced? indigo as follows: (mass of indigo / mass of leaves) c) Try putting the plants in the dark for a few days x 100. You could compare the yield from fresh and (cover them with black plastic). Does this have an dried leaves, or compare it with that of other indigo effect on the amount of indigo produced? What sources such as Indigofera tinctoria. can you conclude about the metabolism of isatan Using indigo as a dye B in the plant? Our experiment involves using indigo to dye wool. d) Investigate the effect of other treatments to the Can indigo be used to dye other materials? You could plants or the cut leaves. compare natural materials such as cotton, linen and e) Test the effect of varying the method of the silk with synthetics or synthetic mixes (e.g. polyester extraction, for example using different kinds of cotton, cotton lycra). alkali. The effectiveness of indigo production Investigating other dyes a) Which produces more indigo, larger, older leaves My students produced dyes from onion skins, from or younger, smaller leaves? Express the amount of indigo obtained by weight and per leaf (count madder (Farusi, 2006), and from myrtle berries. In ad- leaves before extracting them). Which produces dition, they tested how colour-fast their dyes were by

BACKGROUND the most indigo? washing the dyed materials using different methods.

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 45 Image courtesy of Marcel Douwe Dekker; image source: Flickr

The Battle of Hastings begins: under the leadership of William, Duke of Normandy, the Norman forces Image courtesy of PHGCOM; image source: Wikimedia Commons charge the English forces, led by Harold, Earl of Wessex. Studying

chemistry If you found this article useful, you with Pliny may like to browse the other inter- Science in A 12th century manuscript disciplinary articles in the Elder of Naturalis Historia School. See: www.scienceinschool. org/interdisciplinary This activity is part of a larger interdisciplinary project, developed together with 14- to 15-year-old students, to explore ancient scientific Acknowledgement techniques. Pliny the Elder (23-79 AD) was a Roman author and natu- The author would like to thank Dr ralist. His encyclopaedia, Naturalis Historia, brings together much of David Hill from the University of the scientific knowledge of the time. We began each topic by discuss- Bristol, UK, for his tips on extraction ing a passage from Naturalis Historia and then worked out how to rec- of indigo from woad. reate either the experiment described in the text or something similar. In this way, the students began in the same pre-scientific state as Pliny and, through laboratory work and discussion, gained modern scientific Gianluca Farusi teaches chemis- knowledge on each of the topics. The process motivated even the most try at the technical school (Istituto unenthusiastic students. Tecnico Industriale) Galileo Galilei in Other activities in the project include recreating ancient perfumes Avenza-Carrara, Italy, and since 2004, Image courtesy of def110; image source: Flickr (Farusi, 2011), preparing glass tesserae with boric acid, simulating the he has lectured in stoichiometry at the luminescence of the shellfish Pholas dactylus, and preparing iron-gall University of Pisa, Italy, for the degree programme in medicinal chemistry BACKGROUND ink (Farusi, 2007). and technology. He is also the regional tutor for the Italian ministerial project ‘Insegnare Scienze Sperimentali’ References Science in School 6: 36-40. (‘teaching experimental sciences’). For Cooksey CJ (2001) Tyrian purple: www.scienceinschool.org/2007/ secondary schools, Gianluca is also 6,6’-dibromoindigo and related issue6/galls the regional REACH (registration, evaluation, authorisation and restric- compounds. Molecules 6: 736-769. Farusi G (2011) Smell like Julius tion of chemicals) tutor. He has been www.mdpi.com/1420-3049/ Caesar: recreating ancient perfumes teaching for 16 years and nothing 6/9/736/pdf or use the shorter link in the laboratory. Science in School gratifies him more than the delight on http://tinyurl.com/tyriancooksey 21: 40-46. www.scienceinschool. his students’ faces when they grasp a Farusi G (2006) Teaching science and org/2011/issue21/caesar difficult chemical concept. humanities: an interdisciplinary approach. Science in School 1: 30-33. Resources www.scienceinschool.org/2006/ Seefelder M (1994) Indigo in culture, issue1/francesca science and technology. Landsberg, To learn how to Farusi G (2007) Monastic ink: linking Germany: Ecomed Verlagsgesells- use this code, see page 65. chemistry and history. chaft. ISBN 978-3609651606

46 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Image courtesy of Digimist; image source: Flickr

Science education projects

Analysing wine at school

European countries produce more Chemistry than half of the world’s wine – and drink a lot of it too! These hands- on activities for schools reveal the science behind the perfect wine.

By Thomas Wendt C6H12O6 + 2 ADP + 2 Pi paratus. In activity 2, students can

= 2 C2H5OH + 2 CO2 + 2 ATP use the equipment used by hobby winemakers – a vinometer – to he age at which it is legal to The three main factors that deter- measure the alcohol content of the drink alcohol varies from coun- mine the quality of the final product must and wine. try to country, but most teach- are sweetness, alcohol content and 3. A well balanced wine needs a cer- ersT would agree that drinking wine acid content. Using standard meth- tain amount of fruit acid; the total during chemistry lessons is inappro- ods of a commercial wine laboratory, acid content is a very important priate (and potentially dangerous!). these three activities for the school measure, because it directly affects However, producing and analysing laboratory explore how the quality of the flavour. In activity 3, the acid wine at school can be fun and edu- the starting grape juice and the must content is determined by pH titra- cational. These activities, developed (fermenting grape juice) affect the tion. at the science centre Experimentaw1, final product. Each activity takes ap- Four further activitiesw2 can be invite students aged 15-18 to become proximately 20-30 minutes. Image courtesy of def110; image source: Flickr downloaded from the Science in School vintners for a day, using analytical 1. In activity 1, students can deter- website: techniques to explore the changes that mine the sugar content of grape · Activity 1a: in an alternative to take place during the wine-making juice using refractometry. Activity activity 1, students determine the process. 1a (see below) offers an alternative, sugar content of grape juice using Wine is produced by fermenting based on density measurement. density measurement instead of grape juice (which has particularly 2. The exact determination of the alco- refractometry. high levels of sugar) using specialised hol content in commercial wines is · Measuring levels of carbon dioxide, yeast cells. The sugar is converted into performed by distilling the ethanol, one of the products of the fermenta- ethanol and carbon dioxide under then measuring the viscosity of the tion, is a useful way to monitor the anaerobic conditions: distillate using sophisticated ap- progress of the reaction. In activity

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 47

Image courtesy of RobW_; image source: Flickr Image courtesy of tomek.pl; image source: Flickr Image courtesy of JB London; image source: Flickr

Grapes fermenting to make wine Barrels of wine being stored in a cellar to mature

4, students quantify CO2 levels over Determining sugar content The must weight is calculated by: the course of the reaction by liter- The sweetness of the wine is must weight = (density – 1) X 1000 ally shaking the gas out of solution. determined by the amount of sugar · In activity 5, students use light remaining after fermentation, together Where must weight is measured in °Oe transmittance to investigate the dif- with the total acidity of the wine. A and density in g/l. ference that fining (the addition of dry wine has up to 9 g/l sugar and an As a rough estimate, 1°Oe corresponds substances that clarify the wine by acidity level that is at least 2 g/l lower to 2.37 g/l sugar (i.e. about 0.237 °Bx). precipitation) makes to the cloudi- than the sugar content. A medium-dry Therefore, the sugar concentration can ness of the finished product. wine has a sugar content of 9-18 g/l be estimated as: · In activity 6, students examine and an acidity level that should be no fermenting yeast under the micro- more than 10 g/l lower than the sugar sugar concentration = scope. content. A sweet wine has 18-45 g/l of must weight X 2.37 To supply the must used in these sugar. To ensure the correct balance of Where sugar concentration is experiments, you will need to set up sugar, acidity and alcohol in the final measured in g/l. a simple grape juice fermentation at wine, it is important to determine the least one day in advance, using red starting sugar concentration; if neces- The fermentation of all fermentable grape juice (e.g. from the supermar- sary, limited amounts of sugar can be sugar in a solution of 100 °Oe (sugar ket). You will also need some basic added before fermentation. concentration 237 g/l or 23.7 °Bx) yields chemistry laboratory equipment, plus The increased density of the must approximately 100 g/l ethanol (or 10 a vinometer for measuring alcohol (compared to water) is mainly due to wt% alcohol). Because ethanol has a content, a pycnometer (also known as fermentable sugar. Density measure- density of 0.79 g/ml, this converts to a specific gravity bottle) and a refrac- ments or refractometry can be used 12.67 vol% ethanol. Thus: tometer. A description of how to set to measure the sugar content, which alcohol concentration (in % volume) = up the fermentation can be found on in Germany is expressed as the must alcohol concentration (in g/l) X 0.1267 Image courtesy of Rennett Stowe; image source: Flickr the Science in School websitew2. weight and measured in Oechsle Image courtesy of Rennett Stowe; image source: Flickr (°Oe). In the English-speaking world, the sugar content is expressed in Brix (°Bx), which represents the concentration of dissolved sugar, in weight percent (wt%).

48 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Science education projects

Student activity 1: determining sugar content using a refractometer

The amount of sugar in the grape Materials 5. Calculate the missing numbers in juice will determine both the alcohol • Refractometer table 1 using the equations above. content and the sweetness of the • 20 wt% sucrose solution finished wine. In this activity, you will • Grape juice Questions Chemistry use the refractive index to estimate • Paper towels 1. How accurate was your result for sugar content. • Pipette the sucrose solution compared to Refraction is the change in direction the expected value? of light when it passes from one Procedure 2. How reproducible were your medium to another (e.g. from air 1. Pipette 2 drops of the sucrose measurements? Compare them into water). The light-scattering solution onto the glass surface of to that of other groups. behaviour of a solution changes as the the refractometer and close the lid. 3. If you carried out activity 1a concentration of solutes (dissolved 2. Take a reading through the as well, how comparable were substances) increases. A refractometer eyepiece and enter the data in your results for the two methods uses this principle to determine the table 1. (density versus refractometry)? concentration of dissolved particles 3. Using a paper towel soaked in 4. A typical wine has about 12 vol% in a solution. In wine, these are distilled water, clean the glass alcohol. Estimate how much sugar principally sucrose. surface, and then dry it. needs to be added to the grape Most handheld refractometers give juice to obtain 12 vol% alcohol. the concentration of the dissolved 4. Repeat the measurement with substance either in Brix (°Bx), a scale grape juice. defined in terms of sucrose content, or in Oechsle (°Oe). A solution of 20 wt% 20 wt% sucrose Grape juice sucrose in water is 20 °Bx. Oechsle can be converted approximately into Brix by multiplying by 0.237. Must weight (°Oe)

Sugar concentration (°Bx)

Possible alcohol yield (vol%)

Table 1: Calculation of sugar content of samples Image courtesy of Maksud_kr / iStockphoto Image courtesy of Experimenta

Figure 1: Refractometer and scale

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 49 Student activity 2: determining alcohol content

The amount of alcohol obtained by 2. Place a small amount of filtrate in Image courtesy of Experimenta fermentation depends on the sugar the funnel of the vinometer (figure content of the grape juice and the 2B) and wait until the capillary is alcohol tolerance of the yeast strain: full. Keep the remaining filtrate for most yeast strains tolerate up to 16 % activity 3. alcohol. The amount of alcohol can 3. Carefully invert the vinometer be measured quite accurately using a onto a layer of paper towels, then vinometer, a simple device developed observe the level of liquid while it for hobby winemakers. It is based on slowly drops (figure 2C). Once it the principle that the surface tension stays constant, take a reading and Figure 2: Using the vinometer falls as the alcohol content increases. enter it in table 2. In this activity, you will measure the 4. Rinse the vinometer with alcohol content of your must. distilled water, then repeat the Questions measurement using the wine. Materials 1. You determined the sugar Note: The alcohol content of concentration of the grape juice in • Coffee filter the must is probably much lower activity 1. Based on the available • Funnel than that of the wine. This may be sugar in the grape juice, did you • Beakers because the fermentation process is expect a higher alcohol content in • Must not finished. It can also indicate that the wine? • Wine remaining sugar has increased the 2. If the fermentation continued • Vinometer surface tension and is affecting the for longer, would you expect an reading. • Pipette increased alcohol content? • Paper towels Alcohol content (vol%) • Distilled water Procedure Must (filtered) 1. Filter 20 ml must through a coffee Wine filter to remove any remaining yeast cells. Table 2: Alcohol content determined with a vinometer Image courtesy of Edward Stevens; image source: Wikimedia Commons Total acid content Fruit juices can contain several be as high as 15 g/l. It must always Alkaline different acids, including tartaric, be considered in conjunction with malic, citric and oxalic acid, in differ- the amount of remaining sugar (see ing ratios, depending on the type of ‘Determining sugar content’). fruit. The predominant acid in wine is Tartaric acid (molecular weight 150 tartaric acid, which has a pH between g) is a diprotic acid (containing two 3 and 4. However, due to the complex hydrogen atoms per molecule that can mixture of different acids and bases, dissociate in water as protons) that proteins and salts, the total acid con- can be fully neutralised with sodium tent of wine cannot be estimated from hydroxide. Because 1 mol NaOH neu- the pH value alone. Instead, it is de- tralises 0.5 mol tartaric acid (75 g/l), termined by titration to neutrality and 1 ml 0.1 M NaOH neutralises 7.5 mg Acidic expressed as total equivalent amount tartaric acid. of tartaric acid in g/l. The acid content + - + of wine is typically 4-8.5 g/l but can HOOC-CH(OH)-CH(OH)-COOH + 2NaOH → Na -OOC-CH(OH)-CH(OH)-COO Na + 2H2O

50 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Science education projects

Student activity 3: Determination of acidity by titration

All wines contain a certain amount of acid. The winemaker is interested Must Wine in the total acidity, caused mainly by tartaric acid. The total acidity is deter-

pH at start Chemistry mined by titration with diluted sodium hydroxide. Starting volume NaOH (ml) Materials • pH meter End volume NaOH (ml) • Magnetic stirrer • Beaker (250 ml) Volume NaOH used (ml) • Two measuring cylinders (10 ml, 100 ml) Concentration of acid (g/l) • Burette • NaOH solution (0.1 M) Table 3: Determination of the total acidity • Distilled water • 10 ml must (filtered, from activity 2) sides of the beaker or the magnetic Safety note: Wear safety goggles • 10 ml wine stirrer flea. and gloves. See also the general safety 4. Add NaOH solution dropwise note on the Science in School website Image courtesy of Experimenta until neutral pH is reached. Take a (www.scienceinschool.org/safety) and reading on the burette and enter it on page 65. in table 3. Questions • Did you observe any colour In activities 1-3, you analysed the changes? three major factors that determine the • If so, at what pH value? quality of the final product: sweet- • What could be the reason for a ness, alcohol and acid content. Now it colour change? is time to evaluate your product. 5. Calculate the amount of NaOH 1. Is the total acidity within the limits used and the acid concentration. for wine production? Example: We used 14 ml 0.1 M 2. Did the starting grape juice contain NaOH to neutralise 10 ml solution. sufficient sugar to produce the The concentration is therefore (14 x expected alcohol content? 7.5 mg/ml x 100) = 10.5 g/l acid. Figure 3: Set-up of the titration experiment 3. How long would you expect fermentation to take before the process is finished? Procedure Image courtesy of I .. C U; image source: Flickr For each sample (must or wine): 1. Fill the burette with NaOH solution. Enter the starting volume in table 3. 2. Measure 10 ml of your sample and place it in the 250 ml beaker. Add 100 ml distilled water. 3. Start the magnetic stirrer and insert the pH electrode so that the tip is in the sample, but not touching the

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 51 Acknowledgements · Activity 1a: to determine the sugar The author would like to thank content of grape juice using density the wine laboratory of Pfäffle GmbH measurement Experimenta in Heilbronn, Germany, for sup- · Activity 4: to quantify CO2 levels port during the development of over the course of the reaction Experimentaw1 in Heilbronn the activities. He would also like to · Activity 5: to use light transmittance is the largest informal learn- thank in particular Christine Dietrich to investigate the difference that fining and interactive science and Karsten Wiese from the teacher- ing makes to the cloudiness of the centre in southern Germa- training college in Heilbronn for their finished product ny. In addition to the inter- collaboration. active exhibitions and sci- · Activity 6: to examine fermenting ence garden, Experimenta Web references yeast under the microscope. offers more than 30 labora- w1 – Visit the Experimenta website: Resources tory-based programmes for www.experimenta-heilbronn.de school classes and individu- A basic guideline for common experi- w2 – The following materials can al pupils, from kindergarten ments in wine analysis: be downloaded from the Sci- level up to upper secondary ence in School website (www. Schmitt A (1975) Aktuelle Wein school. These programmes scienceinschool.org/2012/issue24/ analytik, Ein Leitfaden für die Praxis. address technology and all wine#resources): Germany: Heller Chemie. ISBN: life sciences as well as pro-

· Instructions for preparing the 978-3-9800498-3-2 BACKGROUND viding teacher training. materials – ideally at least a week in For a comprehensive overview of advance topics that are relevant to the hobby winemaker, see the Fruchtweinkel- Image courtesy of def110; image source: Flickr ler website (www.fruchtweinkeller. de; in German) and the Fruchtwein website (http://met-und-fruchtwein. de, also in German) If you found this activity useful, why not browse the other teaching activities in Science in School? See: www.scienceinschool.org/teaching

Thomas Wendt received his PhD on structural biology from the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, in 1998. Dur- ing his postdoctoral research in the USA and back in Germany, he then focused on protein biochemical and molecular biology methods. After su- pervising numerous students, Thomas decided to concentrate on encourag- ing young people to consider a scientific career. Since 2009, he has been the educational head of the teaching laboratories at Experimenta.

To learn how to use this code, see page 65.

52 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Image courtesy of ESA / XMM-Newton (X-rays); ESA / Herschel / PACS / SPIRE / CD Wilson, McMaster University, Image courtesy of NASA / JPL-Caltech / D Gouliermis (Max- Image courtesy of ESA / AOES Medialab Hamilton, Ontario, Canada (far-infrared and sub-millimetre) Planck Institute for Astronomy, Heidelberg, Germany) and ESA Science topics

More than meets the eye: the exotic, high-energy Universe Physics In the third article in this series on astronomy and the electromagnetic spectrum, learn about the exotic and powerful cosmic phenomena that astronomers investigate with X-ray and gamma-ray observatories, including the European Space Agency’s XMM-Newton and INTEGRAL missions.

By Claudia Mignone and In just half a century, observations the life of stars to the structure of the Rebecca Barnes made at the highest energies have Universe. For an overview of the EM significantly changed our view of the spectrum and its role in astronomy, n the 1960s, the advent of the cosmos. By studying the X-ray and see the first article in this series space age initiated the era of gamma-ray sky, astronomers have (Mignone & Barnes, 2011a). high-energy astronomy. For the discovered several new types of astro- firstI time, astronomers could see the nomical sources and have enhanced Unveiling the birth and death Universe with X-ray and gamma-ray their knowledge of many other types of stars of objects. To examine the Universe eyes. Electromagnetic (EM) radiation Stars are born when gravity causes in this range of the EM spectrumw1, at these wavelengths is emitted by huge clouds of gas and dust to col- the European Space Agency (ESA; cosmic sources with extreme proper- lapse, fragment and form protostars. ties such as exceptionally high tem- see box) operates two missions: the These protostars later grow into fully peratures, extraordinarily high densi- XMM-Newton (X-rays) and INTE- fledged stars when nuclear fusion ties or remarkably strong magnetic GRAL (X-rays and gamma rays) space ignites in their cores. How a star then fields. Ground-based observatories, observatories. The techniques used continues to evolve depends on its however, had been unable to register in X-ray and gamma-ray astronomy mass, with massive stars destined to these rays, which have wavelengths and by these two missions were a shorter life and a more spectacular too short to penetrate Earth’s atmos- introduced in the second article in this demise than their lower-mass counter- phere (figure 1). It took the first space series (Mignone & Barnes, 2011b); this observatories to unveil this turbulent article provides an overview of what parts (figure 2). and ever-changing Universe. these missions have taught us, from It is the early and late stages of

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 53 Physics The article could be very useful in English lessons too, Geography or – once it has been translated – in German, French or Astrophysics other language lessons. Because the article is not too Optics technical, even teachers who are not very familiar with physics could use it. Quantum physics The article could also be used to stimulate discussion, Mass and gravity with questions including: Ages 10-19 This article, the third in a series, describes European 1. Describe the European Space missions research activities within the field of high-energy as- XMM-Newton and Integral. tronomy. The second article in the series described the 2. Give an overview of the electromagnetic spectrum techniques used by two ESA missions, XMM-Newton (including visible, infrared and UV). (X-rays) and INTEGRAL (X-rays and gamma rays); this article describes some of their results, including in- 3. What is the relationship between wavelength, sights into the birth and death of stars, as well as the energy and frequency? more distant Universe. 4. Why do we use space observatories in addition to For older students (16+), the article is ideal for physics ground-based observatories? lessons, where it could be used to address astrophysics 5. Why are gamma rays emitted by hotter sources (the life of stars, cosmic objects, the Big Bang theory), than X-rays? optics or even quantum physics (spectral ranges, relationship between wavelength and energy, EM waves), 6. What are X-ray binaries? mass and gravity. It could also be used in geography 7. What can happen to massive stars at the ends of lessons about the Universe, solar systems and cosmic their lives? objects. To make it accessible to younger students (age of 10- Gerd Vogt, Higher Secondary School for Environment 15 years) as well, I would suggest the teacher selects and Economics, Yspertal, Austria

REVIEW just parts of the article to discuss. ESA/ AOES Medialab Image courtesy of ESA/ AOES

Figure 1: The EM spectrum, with the high-energy regions observed by ESA’s XMM-Newton and INTEGRAL space observatories highlighted. X-rays are emitted by cosmic sources at millions of degrees Celsius; gamma rays by sources at hundreds of millions of degrees Celsius. XMM-Newton detects X-rays at energies of 150-1.5 x 104 eV, whereas INTEGRAL detects both X-rays at energies of 3 x 103-3.5 x 104 eV and gamma rays at 1.5 x 104 keV – 1.0 x 107 eV

xmm-Newton

Integral

54 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Science topics

Figure 2: The life cycle of stars Image courtesy of ESA / AOES Medialab Physics

Image courtesy of NASA / JPL-Caltech / D Gouliermis (Max- Planck Institute for Astronomy, Heidelberg, Germany) and ESA a star’s life cycle that are the most interesting for X-ray and gamma- ray astronomers. Because some very Figure 3: The star-forming region young stars shine brightly under NGC 346 is located in the Small Magellanic Cloud, one of the Milky X-rays, astronomers can detect many Way’s neighbouring galaxies. This of them by looking at star-forming false-colour image combines observa- regions with X-ray telescopes such as tions performed with XMM-Newton XMM-Newton (figure 3). The most in X-rays (blue) with data gathered in massive young stars release highly visible (green) and infrared (red) light energetic radiation and extremely with the Hubble and Spitzer space hot gas, which are observed at X-ray telescopes, respectively wavelengths and influence how other stars form in the surrounding area. Astronomers using XMM-Newton have detected bubbles of hot gas from trons, to very high speeds. As a result, into the history of our galaxy and young massive stars in many regions an abundance of X-rays and gamma performed a census of past superno- w2 of the sky , including the Orion rays are released (figure 4). Further- vae. The results demonstrate that, in Nebula and the star-forming region more, many elements heavier than the Milky Way, supernovae occur on NGC 346. This research feeds into our iron, such as lead, nickel and gold, are average once every 50 yearsw3. understanding of how young mas- synthesised during supernova explo- After a supernova explosion, all sive stars affect star formation around sions (to learn more, see Rebusco et that remains of the massive star is an them – a hot topic in modern astro- al., 2007). Some of these elements are extremely compact and dense object physics. radioactive and eventually decay into – either a neutron star or a black hole. At the ends of their lives, mas- stable isotopes, producing gamma With such a huge mass squeezed into sive stars explode as supernovae (as rays in the process. Astronomers a restricted space, these remnants described in Székely & Benedekfi, using INTEGRAL have surveyed the have exceptionally strong gravita- 2007), heating the surrounding gas Milky Way and found traces of the ra- tional fields and exert an intense pull to extremely high temperatures and dioactive isotope aluminium-26. Just on nearby matter, but they are fairly accelerating particles, such as elec- like archaeologists, they have delved difficult to detect. However, if the

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 55 Image courtesy of CEA / DSM / DAPNIA / SAp / J Ballet and ESA Image courtesy of ESA / AOES Medialab

Figure 4: X-ray image of the super- Figure 5: Artist’s impression of an X-ray binary. With its intense gravita- nova remnant SN 1006 as viewed tional field the black hole on the right draws matter from its companion, with XMM-Newton. This object a blue super-giant star, on the left. The stripped material spirals around is the remains of a supernova that the black hole, forming an accretion disc, which shines brightly at the was seen by Chinese astronomers highest energies. Two powerful jets of highly energetic particles stem in 1006 AD. Visible in the upper- from the vicinity of the black hole left and lower-right corners are shock waves where particles such as electrons are accelerated to very high speeds ample, gamma rays from Cygnus X-1, ESA’s XMM-Newton and INTEGRAL observed using INTEGRALw4, helped are thus ideal tools to hunt for astronomers to better understand how active galaxies and to investigate matter is accreted via a disc onto this the mechanisms that power them. neutron star or black hole is part of a black hole and partly expelled in two Astronomers cannot see all the binary stellar system (two stars orbit- symmetric jets. necessary details in more distant high- ing around a common centre of mass), energy sources, so they also collect it may start devouring matter from its The distant Universe data from as many nearby active companion star; the accreting matter High-energy astronomers not only galaxies as possible. By combining then heats up to millions of degrees, observe the birth and death of stars data from close and distant galaxies, emitting X-rays and gamma rays. This within the Milky Way and nearby astronomers have figured out how high-energy emission can be used to galaxies, but also use X-rays and reveal the presence of a neutron star super-massive black holes accrete gamma-rays to investigate the much or black hole. matter via a disc, and how these discs more distant Universe – including These systems are called X-ray bina- may be surrounded by absorbing super-massive black holes and w5 ries (figure 5) and were discovered in clouds of gas . clusters of galaxies. the late 1960s via X-ray observations. On a still larger scale, galaxies tend Back then, neutron stars and black All large galaxies harbour super- to assemble in clusters of up to several holes had only been predicted by massive black holes at their cores, thousand galaxies. These clusters are theory, so these observations provided with masses a few million to a few the largest structures in the Universe the first proof of their existence. Since billion times that of the Sun. Some to be held together by gravity, and re- then, several generations of space- galaxies, known as active galaxies, lease a diffuse X-ray glow. This glow, based observatories have helped contain super-massive black holes first observed in the 1970s, revealed astronomers to learn more. XMM- that, unlike the one in the centre of that the intergalactic space in a cluster Newton and INTEGRAL have studied the Milky Way, are active. Devouring contains an enormous amount of hot many X-ray binaries (which may matter from their surroundings, gas. Together with other observatories also release gamma rays), revealing these black holes release high-energy that probe the sky across the EM spec- important details about the physics of radiation as well as powerful jets of trum, XMM-Newton has observed black holes and neutron stars. For ex- highly energetic particles (figure 6). hundreds of galaxy clusters (figure 7).

56 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Science topics

Image courtesy of ESA / XMM-Newton (X-rays); ESA / Herschel / PACS / SPIRE / CD Wilson, McMaster University, Image courtesy of NASA / ESA / R Massey (California Institute Hamilton, Ontario, Canada (far-infrared and sub-millimetre) Image courtesy of ESA / ESO / Subaru / R Gobat et al. of Technology)

Figure 6: The nearby active galaxy Figure 7: Observations of the very Figure 8: This map compares the Centaurus A (NGC 5128). This false- distant galaxy cluster CL J1449+0856 distribution of ‘normal’ matter, traced Physics colour image combines observations performed in X-rays (purple glow) via hot gas seen by XMM-Newton (in performed with XMM-Newton in X- with XMM-Newton are superimposed red) and stars and galaxies observed rays (cyan, blue and purple, in order onto an image taken with ground- with the Hubble Space Telescope (in of increasing energy) and data gath- based telescopes at near-infrared grey), to the distribution of the invis- ered at longer, far-infrared (yellow) wavelengths. Most objects visible in ible dark matter (in blue), which has and sub-millimetre (red) wavelengths the image are very faint and distant been inferred from the gravitational using ESA’s Herschel Space Observa- galaxies. The galaxies belonging to lensing effect. The map demon- tory. At X-ray wavelengths, a number the galaxy cluster are visible as a strates how ‘normal’ matter across of foreground point-like sources are clump of faint, red objects. With a the Universe follows the structure of visible: these are X-ray binaries be- temperature above 20 million Kelvin, an underlying ‘scaffolding’ of dark longing to our galaxy, the Milky Way the hot gas pervading the intergalac- matter tic space shines brightly in X-rays

These include a very distant cluster energy sky, recording sudden violent www.scienceinschool.org/2007/ that is one of the earliest structures to outbursts of X-rays and gamma-rays. issue5/fusion have formed in the Universew6, just 3 By continuing to unveil celestial won- Székely P, Benedekfi Ö (2007) Fusion billion years after the Big Bang. This ders to astronomers, these remarkable in the Universe: when a giant star may sound like a very long time, but space observatories are helping to dies.... Science in School 6: 64-68. it is less than one quarter of the Uni- solve the mysteries of our Universe. www.scienceinschool.org/2007/ verse’s present age. issue6/fusion References Galaxy clusters are located in the Web references densest knots of the cosmic web, the Mignone C, Barnes R (2011a) More w1 – To learn more about X-ray and gigantic network of structure that than meets the eye: the electromag- gamma-ray astronomy at ESA, makes up the Universe and consists netic spectrum. Science in School watch Rebecca Barnes in Episode 5 mostly of invisible dark matterw7. 20: 51-59. www.scienceinschool. of the Science@ESA vodcast: The un- Using XMM-Newton, astronomers org/2011/issue20/em tamed, violent Universe. See the ESA have spotted matter where it is most Mignone C, Barnes R (2011b) More Science and Technology website densely concentrated, thus tracing the than meets the eye: unravelling (http://sci.esa.int/vodcast) or use distribution of cosmic structure across the cosmos at the highest energies. the direct link http://tinyurl.com/ the Universe (figure 8). Science in School 21: 57-64. esaepisode5 From the birth of a star to the www.scienceinschool.org/2011/ w2 – Find out more about how XMM- structure of the Universe – what next? issue21/em Newton helped in studying the X-ray and gamma-ray observatories, Rebusco P, Boffin H, Pierce-Price D star-forming region NGC 346 and including ESA’s XMM-Newton and (2007) Fusion in the Universe: detected a hot-gas bubble in the Ori- INTEGRAL, continue to keep a close where your jewellery comes on Nebula. See www.esa.int/science watch on the ever-changing, high- from. Science in School 5: 52-56. and http://sci.esa.int/xmm-newton

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 57 Image courtesy of tlindenbaum; image source: Flickr

respectively, or use the direct links w5 – Read more details of ESA’s All education materials produced by http://tinyurl.com/7xo9qez (NGC findings about active galaxies. See ESA are freely available to teachers 346) and http://tinyurl.com/28d8ac http://sci.esa.int/xmm-newton in the 18 ESA member states. Many (Orion) (XMM-Newton) and http://sci. are translated into several European w3 – Learn how INTEGRAL identified esa.int/integral (INTEGRAL) or languages. the supernova rate for the Milky use the direct links http://tinyurl. Learn more about the activities of the Way and how XMM-Newton helped com/om5sar and http://tinyurl. European Space Agency’s Directo- to analyse the remnants of the Tycho com/3rfws48 rate for Science and Robotic Explo- supernova. See www.esa.int/ w6 – Read about how XMM-Newton ration. See: http://sci.esa.int science or use the direct links helped discover an old galaxy View the full series of articles about http://tinyurl.com/72mhz4s cluster in the young Universe. See astronomy and the EM spectrum. (Milky Way) and http://tinyurl. http://sci.esa.int/xmm-newton or www.scienceinschool.org/em com/752zbh6 (Tycho) use the direct link: http://tinyurl. You may also like to browse the rest of com/5vcf3wz w4 – The ESA website has more infor- the astronomy and space science ar- mation about X-ray binaries. w7 – Learn about the first 3D map of ticles in Science in School. See www. Find out how gamma rays from the the Universe’s dark matter scaf- scienceinschool.org/astronomy and Cygnus X-1 jets were observed with folding. See: www.esa.int or use www.scienceinschool.org/space INTEGRAL (‘Integral spots matter a the direct link: http://tinyurl. millisecond from doom’). See www. com/8r3gw7c esa.int/science or use the direct link w8 – For more information on the Claudia Mignone, Vitrociset http://tinyurl.com/6sxhlqx European Space Agency, visit the Belgium for ESA – European Space Learn about how Supergiant Fast ESA website (www.esa.int). Agency, is a science writer for ESA. X-ray Transients were observed w9 – Find out more about EIROforum. She has a degree in astronomy from by XMM-Newton (‘Neutron star See: www.eiroforum.org the University of Bologna, Italy, and caught feasting on clump of stellar Resources a PhD in cosmology from the Univer- matter’). See http://sci.esa.int/ sity of Heidelberg, Germany. Before xmm-newton or use the direct link ESA has produced many more educa- joining ESA, she worked in the public http://tinyurl.com/7caahph tion materials. See: www.esa.int/ outreach office of the European South- educationmaterials ern Observatory (ESO). Rebecca Barnes, HE Space Op- erations for ESA – European Space More about ESA Agency, is the education officer for the ESA Science and Robotic Explora- tion Directorate. She has a degree in physics with astrophysics from the University of Leicester, UK, and previously worked in the education and The European Space Agency (ESA)w8 is Europe’s gateway to space, organising space communications departments programmes to find out more about Earth, its immediate space environment, of the UK’s National Space Centre. our Solar System and the Universe, as well as to co-operate in the human To find out more about the education exploration of space, to develop satellite-based technologies and services, activities of the ESA Science and Ro- and to promote European industries. botic Exploration Directorate, contact The Directorate of Science and Robotic Exploration is devoted to ESA’s space Rebecca at [email protected] science programme and to the robotic exploration of the Solar System. In the quest to understand the Universe, the stars and planets and the origins of life itself, ESA space science satellites peer into the depths of the cosmos and look at the furthest galaxies, study the Sun in unprecedented detail, and explore our planetary neighbours. ESA is a member of EIROforumw9, the publisher of Science in School.

See all ESA-related articles in Science in School. To learn how to www.scienceinschool.org/esa use this code, see page 65.

58 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Science topics Image courtesy of tlindenbaum; image source: Flickr The new definition of crystals – or how to win

a Nobel Prize Chemistry

Why is symmetry so central to the understanding of crystals? And why did ‘forbidden’ symmetry change the Physics definition of crystals themselves?

By Mairi Haddow Image courtesy of Mark Schellhase; image source: Wikimedia Commons

Common salt (sodium When asked to think of a crystal, you chloride) might think of those that are visible to the naked eye, such as:

Gypsum (calcium sulphate dehydrate) Image courtesy of Tjflex2; image source: Flickr

Cinnamon stone (Ca3Al2Si3O12)

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 59

Image courtesy of Tjflex2; image source: Flickr Image courtesy of tlindenbaum; image source: Flickr Image courtesy of Mairi Haddow tudying crystalline materials Figure 1: Wallpaper illustrating Figure 2: The unit cell (top) and is one of the most powerful translational symmetry in two dimen- crystal structure (bottom) of sodium analytical techniques available sions. The parallelograms indicate chloride, derived by repeating the toS scientists. If it is possible to grow the repeating unit unit cell along three directions: x, a single crystal of a salt, molecule, y and z. Typically, the sizes of unit protein or even a whole virus, then cells range from a few ångströms it is usually possible to identify not (10-10 m) for simple salts (the unit only its connectivity (what atoms are cell of sodium chloride is 5.64 Å), to a few tens of ångströms for small bonded to what), but also its bond molecules, up to several hundred lengths, bond angles and molecular ångströms for protein crystals conformation (what shape a flexible molecule adopts). From the study of protein crystals, it is often possible to elucidate how that protein works in the body and where its active sites are. Image courtesy of Mairi Haddow Crystals are inherently beautiful, largely thanks to their symmetry. Con- ventionally, all crystals were thought thinking about patterned wallpaper, to have one property in common: which usually has this property – if translational symmetry in three di- hung properly. This means that we mensions. Indeed, this is how crystals can draw a parallelogram (tile) con- were originally defined – as materials taining a certain pattern, and by stack- in which the constituent atoms, mole- ing the tile in two directions, derive cules, or ions are packed in a regularly the wallpaper pattern (figure 1). ordered, repeating three-dimensional In a similar way, we can derive a pattern. Translational symmetry is 3D crystal structure from a ‘box’ of best illustrated in two dimensions by atoms, by repeating the box along the

Chemistry Atomic structure Suitable comprehension questions include: Physics Diffraction 1. From the article you can deduce that it is possible Earth science Waves to grow a crystal of: Maths Symmetry a) A salt Art Ages 11-19 b) A molecule Crystallography c) A virus As the author writes, “crystals are inherently beauti- d) A bacterium ful,” but students often regard crystallography as a dif- 2. With which of the following can diffraction analy- ficult and boring subject. For these students and for sis of crystals NOT be performed? their teachers, Mairi Haddow’s article is a valuable re- a) X-rays source to look at crystals with a new and inspiring ap- b) Radio waves proach. In this enjoyable article, the topic is explained c) Neutrons in clear and precise language, together with beautiful d) Free electron laser and impressive pictures (for example the one about 3. With which of the following types of tiles is it pos- wallpaper and translational symmetry). sible to completely cover a 2D surface? The article could be used in school within chemistry a) Triangles, squares, pentagons, and hexagons (solid structures), physics (diffraction, waves, atomic b) Triangles, rectangles and heptagons structure), earth science (mineralogy, crystallography), and maths (symmetry) curricula. These subjects, with c) Triangles, squares, rectangles and hexagons the addition of art history (tiling), offer different inter- d) Squares, rectangles and pentagons

REVIEW disciplinary opportunities. Giulia Realdon, Italy

60 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Science topics Public domain image (recycling symbol); other images courtesy of Mairi Haddow Image courtesy of Mairi Haddow Image courtesy of Mairi Haddow

Figure 3: Unit cell of sodium chloride Figure 4: Examples of shapes with Figure 5: Packing of polygons: it is showing three mirror planes (col- two-fold or mirror symmetry (two not possible for objects with five-fold oured yellow) of diamonds), three-fold (recycling rotational symmetry (pentagons) to be symbol), four-fold (Celtic knot) and packed together without leaving gaps six-fold symmetry (star) (grey shading) between them. In contrast, triangles, squares and hexagons can be packed without gaps Chemistry Physics

x, y, and z axes. The repeating box is (Shechtman et al., 1984). So why was have additional symmetry, such as known as the unit cell (figure 2). this idea so contentious? Because these mirror symmetry. For example, by crystals seemed to have symmetries looking at the unit cell of sodium chlo- Symmetry in crystals and that are forbidden in periodic systems. ride, we can see that each half is the quasi-periodicity In addition to translational sym- mirror image of the other (figure 3; see Crystals that have such translational metry, most periodic crystal structures also figure 4).

symmetry in three dimensions are Image courtesy of Phillip Westcott, National Institute of Stand- Rotational symmetry is also pos- formally referred to as periodic crystals ards and Technology sible. This means that if we take an because the structures have a pattern object and rotate it around a central that repeats at a certain distance or point by a certain number of degrees, period. In 2011, however, the Nobel it will look the same (figure 4). Prize in Chemistry was awarded to When a pattern or crystal has trans- Dan Shechtman for his discovery of lational symmetry and is periodic, quasi-periodic crystals. These crystals two-fold, three-fold, four-fold and six- are not periodic – they do not possess fold rotational symmetries are all pos- translational symmetry – but still have sible, but five-fold, or indeed seven- local order. They have the same re- fold or higher symmetry, is not. This is peating unit at different points in the because triangles, rectangles, squares and hexagons may all be packed in crystal, but not at periodic intervals. Dan Shechtman explaining the atomic The recent recognition of this work is structure of quasi-periodic crystals at a 2D space without leaving any space a triumph of Shechtmann’s persever- meeting at the National Institute of Stand- in between. In contrast, pentagons, ance over the ridicule that he received ards and Technology, USA, in 1985 – just heptagons and higher polygons may when he first published his work months after he published his discovery not (figure 5).

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 61 Image courtesy of Mairi Haddow Image courtesy of Mairi Haddow

Figure 6: Young’s diffraction experi- Figure 7: Layers of atoms in sodium ment, showing the interference of light chloride that act similarly to slits in a passing through a diffraction grating diffraction grating Image courtesy of Mairi Haddow

Figure 8: Derivation of Bragg’s law. The extra distance (green path) travelled by the lower X-ray can be shown to be equal to 2d sinθ. The scattered beams will be in phase if and only if the extra distance travelled is equal to a whole number (n) of wavelengths (λ). Thus, a diffraction peak will be visible only if nλ = 2d sinq

How are crystals analysed? act as a complex diffraction grating, ence between the path lengths of two Many students will have performed where the ‘slits’ are layers of atoms in scattered X-rays is equal to a whole Young’s famous double-slit experi- the crystal (figure 7). number of wavelengths, resulting in ment at school, in which a laser is For diffraction to occur, the wave- a measurable diffraction peak. This is shone through two slits in a diffrac- length of the radiation interacting known as Bragg’s law, and the derivation grating, the spacing between with the crystal must be comparable tion is illustrated in figure 8. which is comparable to the wave- to the distance between the atoms. As the crystal is rotated, different length of the laser light. An interfer- Commonly in laboratories, the radia- layers of atoms will satisfy Bragg’s ence pattern can be seen, caused tion will be X-rays (which are scat- law and produce constructive inter- by constructive and deconstructive tered by the electrons in atoms), but ference. This results in a diffraction interference of the waves diffracted by there are other possibilities, such as peak with an intensity related to the the slits (figure 6). electrons or neutronsw1. number and type of atoms in the Crystals are studied using a tech- The crystal is mounted in an X-ray layer, for example as shown in figure nique known as X-ray diffraction, the beam of a selected wavelength, and 9. A typical diffraction experiment theory of which was developed exten- the diffraction pattern is measured will measure thousands to millions of sively in 1913 by William Henry Bragg as the crystal is rotated. For layers reflections, and by careful analysis and his son William Lawrence Bragg, of atoms positioned at an angle θ to can be used to figure out the exact who were jointly awarded the Nobel the X-ray beam, scattered X-rays will structure of the crystal. Prize in Physics in 1915 for their work. be in phase (i.e. have constructive The diffraction pattern produced by In a diffraction experiment, crystals interference) if and only if the differ- a crystal also has symmetry and this is

62 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Science topics Materialscientist; image source: Wikimedia Commons Images courtesy of Mairi Haddow (right and left images); central image courtesy of Image courtesy of Mairi Haddow Image courtesy of Materialscientist; image source: Wikimedia Commons

Figure 9: A typical diffraction pattern Figure 10: X-ray diffraction pattern Figure 11: A single object may pos- from a conventional crystal at one with two-fold rotational symmetry sess five-fold rotational symmetry particular angle. Each bright spot from a periodic crystal (A) and an (top) but these objects may not be (reflection) represents constructive electron diffraction pattern from a combined into a periodic system. interference from a different layer of quasi-periodic crystal, showing 10-fold This occurs, for example, in Penrose atoms. (The shape on the right is the rotational symmetry (B). For compari- tiling (bottom), in which instances shadow of the beam stop, a metal son, the X-ray diffraction pattern from of local five-fold symmetry may be shield which absorbs the unscattered a glass fibre (broadly amorphous, i.e. found, but which does not have

X-ray beam) non-crystalline) material (C) translational symmetry Chemistry

A Physics

Image courtesy of Roger McLassus; image source: Wikimedia Commons related to the symmetry of the crystal. B The diffraction patterns of quasi-periodic crystals have symmetry that is forbidden in periodic crystals, such as five- or 10-fold rotation (figure 10). The structures of these unusual crystals are related to Penrose tilings (figure 11). These are structures that possess local symmetry, but not translational symmetry. Research in this area led to a change in the definition of a crystal by the International Union of Crystallogra- C phy in 1991. Crystals now no longer Studying crystals relies on the analysis need to have translational symmetry: of the interaction of waves with layers of atoms a material is a crystal if it has a sharp diffraction pattern, which quasi-peri- Image courtesy of Mairi Haddow odic crystals certainly do. However, it’s unlikely that the school curriculum will be changed any time soon to reflect this new definition. Very few of these quasi-periodic materials have yet been discovered, and the first natural quasi-periodic

crystal – icosahedrite (Al63Cu24Fe13), a mineral that is probably of meteoritic origin and was found in the Khatyrka polymers, the crystals that school river in eastern Russia – was discov- students grow in the lab are unlikely ered only in 2009. Although more ex- to be anything but periodic, and aside amples have been created since then, from their unusual and interesting and quasi-crystals are now known to properties, quasi-crystals have no real A holmium-magnesium-zinc exist in many metallic alloys and some applications – yet. quasi-periodic crystal

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 63 References ed articles in Science in School: To learn how to grow your own Bindi L et al. (2009) Natural Quasic- www.scienceinschool.org/esrf protein crystals at school, see: rystals. Science 324(5932): 1306-1309. The Institut Laue-Langevin (ILL; Blattmann B, Sticher P (2009) doi: 10.1126/science.1170827 www.ill.eu) operates the most Growing crystals from protein. Shechtman D et al. (1984) Metallic intense steady neutron source in Science in School 11: 30-36. phase with long-range orientational the world. Diffraction studies of the www.scienceinschool.org/2009/ order and no translational symme- neutron beams are used in research issue11/lysozyme try. Physical Review Letters, 53(20): into condensed matter physics, More information about Dan Shecht- 1951-1953. doi: 10.1103/ chemistry, biology, nuclear physics man and his discovery is available PhysRevLett.53.1951 and materials science. on the Nobel Prize website: www.nobelprize.org Web resources The European X-ray Free Electron Laser (European XFEL; www.xfel. Howes L (2011) Quasicrystals scoop w1 – Diffraction analysis is possible eu), due to start operation in 2015, prize. Chemistry World 8(11): 38-41. not only with X-rays, but also with will use X-ray flashes to examine www.rsc.org/chemistryworld/ neutrons and electrons. This is ex- Issues/2011/November/Qua- samples. The basic idea behind a emplified by three of the members sicrystalsScoopPrize.asp or use typical experiment is simple: il- of EIROforum (www.eiroforum. the shorter link: http://tinyurl. luminate a sample by intense X-ray org), the publisher of Science in com/7ek47aw School. flashes and count the photons that For an interview with mathematician The European Synchrotron Ra- are scattered from the sample in different directions. The result is a and symmetry researcher Marcus de diation Facility (ESRF; www.esrf. Sautoy, see: eu) uses the diffraction patterns diffraction pattern. Hayes E (2012) Finding maths where of high-energy X-rays to analyse Resources you least expect it: interview with materials. The experiments carried Marcus du Sautoy. Science in School out at ESRF have applications not Cornuéjols D (2009) Biological 23: 6-11. www.scienceinschool. only in materials science, but also in crystals: at the interface between org/2012/issue23/dusautoy biology, medicine, physics, chemis- physics, chemistry and biology. try, environmental science and even Science in School 11: 70-76. www. If you found this article helpful, you palaeontology and cultural heritage. scienceinschool.org/2009/issue11/ may like to browse the other chem- See the full collection of ESRF-relat- crystallography istry articles in Science in School. See www.scienceinschool.org/ Image courtesy of Alex McPherson chemistry

Mairi Haddow studied chemistry at the University of Edinburgh, UK, has a PhD in chemistry from the Univer- sity of Bristol, UK, and now works as a research fellow at the University of Bristol, in charge of the X-ray diffraction facilities in the School of Chem- istry. She regularly gives demonstrations of the equipment to A-level students (aged 16-18) who take part in the School of Chemistry’s (inappropri- A collage of protein and virus ately named) ‘spectroscopy tours’. crystals, many of which were grown on the USA’s Space Shuttle or the Russian space station, Mir. The crystals, which are suitable for X-ray diffraction analysis, include a fungal protease and To learn how to yellow mosaic virus use this code, see page 65.

64 I Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Publisher: EIROforum, Safety note EIROforum Science topics www.eiroforum.org For all of the activities published in Science in Science in School is published and funded by School Editor-in-chief: Dr Eleanor Hayes, , we have tried to check that all recognised EIROforum, a collaboration between eight of hazards have been identified and that suitable European Molecular Biology Laboratory, Europe’s largest inter-governmental scientific precautions are suggested. Readers should be aware, research organisations, which combines the re- Germany however, that errors and omissions can be made, sources, facilities and expertise of its member or- Editor: Dr Marlene Rau, and safety standards vary across Europe and even ganisations to support European science in reaching European Molecular Biology Laboratory, within individual countries. its full potential. See: www.eiroforum.org Germany Therefore, before undertaking any activity, readers CERN should always carry out their own risk assessment. Biology Editorial board: The European Organization for Nuclear Research In particular, any local rules issued by employers or (CERN) is one of the world’s most prestigious Dr Giovanna Cicognani, education authorities MUST be obeyed, whatever is research centres. Its main mission is fundamental Institut Laue-Langevin, France suggested in the Science in School articles. physics – finding out what makes our Universe work, Dr Dominique Cornuéjols, European Unless the context dictates otherwise, it is assumed that: where it came from, and where it is going. See: Synchrotron Radiation Facility, France · Practical work is carried out in a properly www.cern.ch Monica Talevi, European Space Agency, equipped and maintained science labor atory EFDA-JET the Netherlands · Any electrical equipment is properly maintained The Joint European Torus (JET) investigates the Dr Rolf Landua, European Organization for · Care is taken with normal laboratory operations potential of fusion as a safe, clean, and virtually Nuclear Research (CERN), Switzerland such as heating limitless energy source for future generations. It can create the conditions (100-200 million °C) in the · Good laboratory practice is observed when Dr Dean Madden, National Centre for plasma sufficient for fusion of deuterium and tritium chemicals or living organisms are used Biotechnology Education, University of nuclei to occur – and it has observed fusion power Reading, UK · Eye protection is worn whenever there is any to a maximum of 16 MW. As a joint venture, JET is recognised risk to the eyes Dr Petra Nieckchen, European Fusion collectively used by more than 40 European fusion Development Agreement, UK · Pupils and / or students are taught safe techniques laboratories. The European Fusion Development for activities such as handling living organisms, Agreement (EFDA) provides the platform to exploit Dr Douglas Pierce-Price, European Southern hazardous materials and equipment. JET, with more than 350 scientists and engineers Observatory, Germany Credits from all over Europe currently contributing to the JET Lena Raditsch, European Molecular Biology Science in School is a non-profit activity. Initially programme. See: www.efda.org/jet Laboratory, Germany supported by the European Commission, it is now EMBL Dr Fernand Wagner, European Association for funded by EIROforum. 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www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 I 65 Learning through investigation: Science on Stage visit to El Roure Gros primary school The Catalan primary school El Roure Gros has a unique concept: all learning is done through experimentation and investigation. Science on Stage Germany invited eight teachers from Austria, Germany and Italy to visit the school.

Image courtesy of fatc at21 / iS toc kp ho to

By Elena Lührs international teaching festival in break still determines the style of Copenhagen, where Carmen Alema- learning and teaching today: there is t first glance, the building ny, head of El Roure Gros, and her no separation of school subjects, no of El Roure Gros in Santa colleague Eloi Arisa presented the bell ringing at a certain time to mark Eulàlia de Riuprimer does concept behind their school. One of the end of a lesson, and classroom Anot resemble a school at all. It is small the board members of Science of Stage doors are not closed. At El Roure and very simple; only the yard gives Germany, Ute Hänsler, realised how Gros, all learning is integrative, the impression of a public institution. much other European teachers could interdisciplinary and project-based. In April 2012, eight primary-school benefit from a visit, and primary- The students themselves can propose teachers travelled to Spain to look school teachers who had attended the topics and work on them indepen- behind the façade of this very special festival were invited to take part. dently or in small groups. The projects school. In the 1980s, Carmen Alemany usually last one week and are docu- The idea of the excursion came decided that the school should break mented on paper and with computers about in 2011 at the Science on Stage with administrational rules, and this in a portfolio. The students only ap-

Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org General science Primary

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m I numerous hexagons, stuck them together and created a hemisphere numerous hexagons, stuck The planetarium, a long-term project. Pupils of different ages cut out planetarium, a long-term project. Pupils The ring surrounds the hemisphere A wooden with a diameter of 2.5 m. and is attached to it using angle irons. The whole construction hangs construction whole The to it using angle irons. and is attached on steel ropes from the ceiling. A projector beams the starry sky onto beams the starry sky A projector on steel ropes from the ceiling.

of Wilfried go: the pupils become steady, the inner surface of the sphere. Ready, rtesy Mey u e real astronomers co r

and time is needed to measure speed. He stumbles upon the unit ‘100 and time is needed to measure speed. He units, measurement explains that there are several teacher The feet’. e out school books. One student explains that information on distance out school the different units. Eventually, his students to convert and encourages

group of students and one teacher have a discussion; they work with- a discussion; they work have group of students and one teacher g

students compare the speed of different car types and even measure types and even students compare the speed of different car a tape are sufficient to fill an English lesson with this physics topic. A topic. with this physics tape are sufficient to fill an English lesson m the velocity of light the velocity I What is speed, and how do we measure it? A poster and a measuring do we measure it? What is speed, and how ob Jac dia lau C of y es rt u o c e g a Im letters of the alphabet in kindergarten letters of the alphabet same, and even guess that lenses with different focal points might exist same, and even and asks the older pupils what it might be used for: “To convert energy! To To energy! convert it might be used for: “To and asks the older pupils what of light through a convex lens: they observe that rays can be refracted and can be refracted that rays lens: they observe of light through a convex change luminosity! To vary voltage!” The children use technical terms as a use technical children The voltage!” vary To luminosity! change focused on the same spot, but that the ray in the centre remains unchanged. in the centre remains unchanged. focused on the same spot, but that the ray as digital cameras or laptops and printers is a matter of or laptops as digital cameras student’s project documentation. Handling media such Handling media such project documentation. student’s www.scienceinschool.org matter of course. They take a lamp out of the suitcase and explore the change take a lamp out of the suitcase and explore the change They matter of course. according to age level. Interdisciplinary portfolio folders Interdisciplinary according to age level. and files on the school server gather together all of each together all of each gather server and files on the school consists of summaries, reflections, photos and drawings – reflections, photos and drawings consists of summaries, A recently purchased optics suitcase. The teacher takes out a power transformer transformer takes out a power teacher The optics suitcase. A recently purchased They agree that the distance from the focal point to the lens always remains the point to the lens always agree that the distance from the focal They everyday life how to read and write. Project documentation to read and write. Project documentation life how everyday course for the pupils from an early age. They learn the first learn the first They from an early age. course for the pupils Documentation at El Roure Gros. The pupils learn casually in pupils learn casually The Roure Gros. Documentation at El Image courtesy of fatcat21 / iStockphoto

proach their teachers if they are stuck to raise confident and independent Meyer, Carina Peschek and Monica with their project. humans. The pupils of El Roure Gros Zanella for their contributions to this Inquiry and communication are the perform outstandingly well in public article, and THINK ING for support- main competences taught at El Roure tests compared with other Catalan ing the teacher excursion to El Roure Gros. The key for this concept of primary-school students. And the side Gros. teaching and learning is the docu- effect of this concept: approximately mentation of all learning processes. 70% of El Roure Gros alumni have Web references The pupils begin with drawings in chosen careers in mathematics, science w1 – Science on Stage is a network kindergarten, and go on to learn how or engineering. of local, national and interna- to write and read because of the need The visiting primary-school teachers tional events for teachers, initially to apply these skills for their own were impressed with what they saw. launched in 1999 by EIROforum, documentation. They are not taught “The atmosphere was one of respect the publisher of Science in School. knowledge, but how to gain knowl- and the children were taken seriously: At each national Science on Stage edge themselves. The aim of this the teachers responded to all the chil- event, a delegation of teachers is concept is to raise independent young dren’s thoughts and questions,” said selected to represent their country people who are capable of taking Monica Zanella from Italy. Wilfried at the Science on Stage international responsibility and initiative. During Meyer and Kirstin Yüzüncü from Ger- teaching festival. the two-day visit, the Science on Stage many commented, “We were amazed The next international festival will teachers had the opportunity to see to see what a school can achieve be held on 25-28 April 2013, in this concept in action. with such limited resources when it Słubice-Frankfurt (Oder) on the The two-storey building houses 142 doesn’t have to constantly struggle Polish-German border. During the pupils and 12 teachers. The pupils are with standards, competencies, exam- festival, 350 teachers from 27 coun- allocated to the kindergarten (ages 3 oriented content; at El Roure Gros, tries will share their most innova- to 5), the initial circle (6 to 7), the mid- all the teachers’ energy is poured into tive teaching ideas in workshops, dle circle (8 to 9) and the upper circle the children, their interaction with the on-stage performances and the (10 to 11), although doors are left open world and their education.” teaching fair. Participation is free for to encourage communication and col- Although it may not be possible for delegates. For other science teach- laboration between groups. Much of all teachers to recreate the El Roure ers, there will be a limited number the work in the school is based on co- Gros concept in their own schools – of places for which a registration operation: between teachers, between particularly in countries like Germany fee will be charged. See the Science pupils, and between teachers and where school curricula are structured on Stage Europe website for details. pupils. The school is equipped with quite strictly – they can take away www.science-on-stage.eu 60 laptops and desktop computers, a useful ideas. One important aspect w2 – Learn more about Science small sound studio and a planetarium that could be adopted at any school on Stage Germany: built by the pupils. The everyday is more open documentation of the www.scienceonstage.de language is Catalan, although Spanish learning process. In the occasional is taught from an early age, and older lesson, teachers could also reduce Resources pupils learn English. their involvement, allowing children Excursions to science centres, to take the lead in deciding what top- To learn more, browse the other museums, industry or natural sur- ics to explore, and how they want to Science on Stage articles in Science in roundings take place every three document them. In this way, children School. www.scienceinschool.org/sons months. The school aims to include gain the spirit of exploration while the natural and social surroundings, learning. such as the village, its inhabitants and Thanks to its unusual concept, the its geography, in the teaching process. Catalan primary school El Roure Gros “A child is born with a lot of innate is a prototype for schools throughout knowledge,” explains Carmen, “but Europe: competence-based learning it needs to get to know its natural and in inspiring learning environments – social surroundings, and its customs. successful, sustainable and suitable The teacher needs to accompany the for children. child in its process of exploring its surroundings.” Acknowledgement The school’s aim is not to produce Science on Stage Germany would To learn how to use this code, young scientists and engineers but like to thank Claudia Jacob, Wilfried see www.scienceinschool.org/help#QR

Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Teacher profile

Making physics flourish Image courtesy of stock photos for free.com in Poland: Maria Dobkowska Physics teacher Maria Dobkowska describes the challenges of remaining creative within a strictly defined national curriculum and of working with children with disabilities. Physics

By Katy Hewis There can be no doubt that the After my time as a trainee teacher, I recipient of that recognition, Maria knew for sure that it was the job for hen the first two eminent Dobkowska, followed the right career me.” speakers at a national con- path: her happy 39 years of teaching Maria’s enthusiasm has served her

ference for physics teachers experience in Poland prove it. “I’ve well, particularly when facing the General science Win Poland pause in their opening com- always been a social person. I liked considerable challenges posed by the ments to thank you for inspiring them working with people,” she explains, Polish school system (see box). “In Po- to study physics, you must be doing “and I knew that working in a scien- land we have strictly defined national something right. tific laboratory wouldn’t interest me. curricula for each separate subject. You can only introduce your own topics in extra-curricular activities – outside of lessons,” Maria explains.

Image courtesy of Boguslawa Rotter Unfortunately, according to Maria, successive education reforms in Po- land have reduced the number of lessons in physics, but not the extent of the material that needs to be covered before the national exams. “Even during extra-curricular activities, teachers are more focused on preparing students for the examinations than on expanding or introducing new content.” Furthermore, the lack of funds for extra-curricular activities means that the needs of gifted and talented students are not always met. Many teachers would struggle in such a constrained system but Maria has risen to the challenge. In doing so, she has created resources that have helped other teachers both nationally Maria’s school and internationally. ‘science picnic’ “I started a student competition, ‘Taking photos of physical phenom-

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 Images courtesy of Julia Wojciechowska (aged 15)

In these photos entered in the student competition, ‘Taking photos of physical phenomena’, the student demonstrated how water expands as it freezes

ena’, initially in my school. It was conducting similar competitions – this to the needs of lower secondary- a great success: some of the photos makes me very proud.” school physics teachers who wanted were so good that they were used as About 10 years ago, together with to make their lessons more engaging illustrations in the physics handbooks Miroslaw Los, who teaches physics but lacked the time and / or equip- for lower secondary school. Many and information and communica- ment. Over time, Maria and Miroslaw cities in Poland are now successfully tions technology (ICT), Maria began extended this resource to include ani- making videos of interesting physics mations and interactive simulations. experimentsw1. This was in response Today, all the materials are included

The Polish education system

Szkoła podstawowa Stage 1: age 7-10 (primary school) All teaching is integrated, with no separate subjects. Stage 2: age 10-13 Separate subjects are introduced. The only scientific subject at this stage is nature, which consists mainly of biology and geography, with a small amount of physics and chemistry. The students receive three hours per week of nature lessons.

Gimnazjum Stage 3: age 13-16 (lower secondary school) Teaching is based on separate subjects – biology, chemistry, geography and physics. For each of these subjects, the students receive 130 hours over the three-year period. For example, they may receive one hour per week in the first year, two in the second year and one in the third year.

Liceum Stage 4: age 16-19 ogólnokształcqce As of 2012, science is taught as separate subjects only in the first year of (upper secondary Stage 4. Per subject, the students receive one hour of lessons per week. school) For the second and third years of Stage 4, students choose to focus on either science or humanities. Over those two years, students who focus on science receive four hours of lessons per week for each science subject (biology, chemistry, geography and physics). Students focusing on humanities receive one hour per week of integrated science (nature) lessons. BACKGROUND

Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Teacher profile

Images courtesy of Piotr Dobranowski (aged 15) A B C

In these photos entered in the student competition, ‘Taking photos of physi- After many years of teaching, fol- “The way of working with these cal phenomena’, the student dem- lowed by a long career break to raise students was something entirely new onstrated how to vary the buoyancy her family, Maria was ready for a new for me and it was a real challenge. I

of a bottle by filling it with different challenge. In 1994, she started teach- had to change my working methods. Physics amounts of coloured water, thus varying physics at a newly established Thanks to this school, I became more ing its weight. integrated school, an open-plan school creative, innovative and courageous A: When the weight of the bottle is where able-bodied and physically in my selection of experiments and less than the upward force of buoy- disabled students (aged 6-19) learn demonstrations. I started to give my ancy, the bottle floats together. In each class, there are about students more freedom to find their B: When the weight of the bottle is five students with disabilities and no own solutions and I also started equal to the upward force of buoy- more than 20 students in total. In ad- to work with projects – an almost ancy, the bottle is suspended in the General science water column dition to the subject teacher, there is unknown method in Poland.” This C: When the weight of the bottle is a special educator in the classroom, creativity led to Maria’s involvement greater than the upward force of buoy- and students with severe disabilities in three international, EU-funded ancy, the bottle sinks have a personal assistant, for example school projects, such as ‘Handicapped to help with writing. There are also children in Europe get to know each specialists to help students overcome other’, which integrated science with in Polish physics textbooks and are difficulties in speaking, reading and art, food and cultural heritage. available on CD, as well as via the memorising, and to provide medical Of course, even the best teacher’s website of Wydawnictwa Szkolne i assistance. Such schools are rare in lessons don’t always go to plan. “Last Pedagogiczne, one of the oldest and Poland. year, I had been preparing a scien- largest educational publishing houses Image courtesy of Boguslawa Rotter in Poland. Maria has also co-authored many print publications to support Maria explains the transit of Venus the teaching and learning of physics. Furthermore, through her involvement in Science on Stagew2, a network of local, national and international events for teachers, Maria has shared her ideas with teachers from many other European countries. Not only has she presented projects at three Science on Stage international teaching festivals, but she has helped to organise Science on Stage Poland since 2006. Together with other teachers involved in Science on Stage, she has contributed to the international publications Teaching Science in Europe: What European Teachers Can Learn From Each Otherw3.

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 tific experiment to show that fresh Science on Stage publication Sci- tries will share their most innova- eggs sink in water, but that as they ence Teaching: Winning Hearts and tive teaching ideas in workshops, get older, their density changes until Minds. See: www.science-on-stage. on-stage performances and the they float. I don’t remember how long de/?p=255 or download the PDF teaching fair. Participation is free for I kept these eggs in my lab before I directly from: http://tinyurl.com/ delegates. For other science teach- decided to use one of them in another bnjysh6 ers, there will be a limited number lesson to show that eggs are fragile. A Polish explanation of the project of places for which a registration I wanted to show it spectacularly (‘Kamera na podczerwień w nauczaniu fee will be charged. See the Science and I dropped an egg onto a tray on przedmiotów przyrodniczych’) is avail- on Stage Europe website for details. the floor. The stinking gas from the able on the website of Wydawnict- www.science-on-stage.eu egg quickly spread throughout the wa Szkolne i Pedagogiczne. See: w3 – As part of her involvement in whole school! The students were very www.wsipnet.pl/edukacja/index. Science on Stage, Maria contributed amused by what had happened dur- html?id=65 or use the shorter link: to the publications Teaching Science ing their lesson. Other students still http://tinyurl.com/candk8j in Europe: What European Teachers ask when I am going to make such an The Naked Scientists website of- Can Learn From Each Other. The egg again!” fers instructions for making your PDFs of all three publications (2006, It could be argued that the success own infrared camera. See: www. 2008 and 2010) can be downloaded of a teacher can be proven by the suc- thenakedscientists.com or use the from the Science on Stage website. cess of their students. Maria recounts, direct link: http://tinyurl.com/ Visit: http://science-on-stage. “Michal is severely disabled with cer- crxehzh de/?p=255 ebral palsy: he is confined to a wheel- chair and has difficulty with speech w2 – Science on Stage is a network Resources and co-ordination. I taught him phys- of local, national and international events for teachers, initially If you enjoyed this article, why not ics at our gimnazjum and liceum and browse all the teacher profiles in now he is finishing his third year of launched in 1999 by EIROforum, the publisher of Science in School. Science in School? www.sciencein- physics at Warsaw University!” school.org/teachers In an ideal world, Maria would like At each national Science on Stage more science lessons per week and event, a delegation of teachers is more freedom within the curriculum. selected to represent their country More funds for equipment would at the Science on Stage international mean more hands-on experiments. teaching festival. Open science labs, maybe at universi- The next international festival will ties, would encourage students inter- be held on 25-28 April 2013, in ested in pursuing physics at a higher Słubice-Frankfurt (Oder) on the level. Above all, however, Maria is Polish-German border. During the To learn how to use this code, keen to continue her professional de- festival, 350 teachers from 27 coun- see www.scienceinschool.org/help#QR velopment: “Conferences and workshops are very helpful, and despite Image courtesy of Natalia Witt my many years of work as a teacher, I can still learn something new.” That’s an attitude worth passing on to any student.

Web references w1 – One of the activities that Maria and Miroslaw devised together involves using infrared cameras, for example to visualise the transfer of energy from a bouncing ball to the surface it bounces on. For an English description of the Maria representing her school at project, see pages 66-67 of the the national ‘science picnic’

Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Reviews

The Eduspace website

By the European Space Agency

Reviewed by Marco Nicolini, Italy

f you teach geography, earth sci- organised in geographical information the programmes available on Edus- ence, physics, or even information systems (GIS). Sub-sections include re- pace are accompanied by succinct but and communications technology mote sensing in-depth; the history of complete tutorials, plus online help. (ICT)I or biology, you should defi- EO; satellite orbits; and EO satellites. Also helpful are the case studies of nitely visit the Eduspace website from The most valuable aspect of Edus- EO applications in the ‘Earth from the European Space Agency (ESA). pace for teachers is the wealth of space’, ‘environmental issues’ and Physics Completely revised in 2010, the latest software-based activities that can ‘Envisat for schools’ sections. These version offers a wide range of tools be downloaded from the resources case studies focus on regions across and exercises to help users learn about section. Using these, teachers can the world, and are good examples of and apply Earth observation concepts develop multidisciplinary activities how you can use Eduspace to down- and techniques. The site’s entire con- for their students. For example, the load and process ESA satellite images tents are available in English, Danish, image catalogue viewer allows you to of your region, your town, or even

Dutch, French, German, Greek, Ital- search and download satellite images your backyard. General science ian, Portuguese and Spanish. from the huge image database of the In short, the Eduspace website pro- Earth observation (EO) is the name main ESA-supported missions. The vides teachers with a vast supply of given to a set of activities for gath- viewer’s companion, LEOworks, is a material that can be integrated into ering data about Earth’s physical, simple but powerful programme for their lessons. chemical and biological systems. The processing the images. For example, Details majority of EO activities are now per- it allows you to crop, zoom and resize formed almost entirely by satellites, images; measure distances; check geo- URL: www.esa.int/eduspace which is why space agencies such as graphical coordinates; produce statis- Resources ESA play a central role in providing tical histograms; combine and animate EO data. Amongst other applica- a series of images; and use GIS tools. To learn more about GIS and Arcgis- tions, EO is used to monitor elevation, ICT teachers can show students how explorer, see: changes in vegetation (in cultivations numbers represent coloured pixels, Kerski J (2010) GIS: analysing the or during deforestation), weather and whereas geography, earth science and world in 3D. Science in School 15: climate, disasters and the behaviour of physics teachers can focus on the in- 34-38. www.scienceinschool. the oceans and atmosphere. These are terpretation of those pixels and other org/2010/issue15/gis all topics that science teachers can use data. If you found this review interesting, to develop multidisciplinary activities. Another useful programme to why not browse all the resource The Eduspace website offers ac- download from the Eduspace web- reviews in Science in School? See: tivities and projects involving EO site is Arcexplorer, with which you www.scienceinschool.org/reviews techniques and applications that are can view and query geographic data suitable for secondary-school science stored on your computer or the web, teachers to include in their lessons, display a wide variety of image for- as well as for interested secondary- mats, and create maps. Note that this school students. programme has now been superseded A section on remote sensing helps by Arcgisexplorer, which includes to familiarise beginners with remote- GPS integration, geo-referencing and sensing concepts, satellite-based EO geo-tagging tools and can be down- and data acquisition, and shows them loaded from the website of software To learn how to use this code, how the information can be used and company Esri (www.esri.com). All of see www.scienceinschool.org/help#QR

www.scienceinschool.org Science in School I Issue 24 : Autumn 2012 The Periodic Table of Videos website

By the University of Nottingham, UK

Reviewed by Marie Walsh, Ireland

here are a number of reasons The home page features an inter- to a sister site, Test Tubew1, which is why you might not want to active periodic table linked to short another brainchild of Brady Haran, read this review: perhaps you videos on each element. Caesium, for featuring a collection of videos. Test doT not teach chemistry, you are re- example, is presented in the context Tube started in 2007, when Brady was sisting the use of video clips in your of its use in exact time measurement, appointed filmmaker-in-residence for teaching, or you are looking for non- and by showing its explosive reaction the Nottingham Science City web- English teaching materials. These with water. Most videos are about 10 sitew2. Test Tube’s purpose is to show are not good reasons though, as you minutes long, and in the classroom what science is really like, from the will see. I challenge you to visit The you may decide to use all or just part highs of exciting breakthroughs to Periodic Table of Videos website, as of a clip. Some videos are available on the lows of tedious experiments. The it might just convert you. Youtube in other languages, such as Periodic Table of Videos grew from You may feel that the website is Spanish, Portuguese, Indonesian or this idea. primarily a resource for chemistry Italian. Although the elements of the peri- teachers. However, chemistry sits The Periodic Table of Videos is odic table are the main focus of The directly between physics on the one produced by a multidisciplinary team Periodic Table of Videos website, it hand and biology on the other, so of scientists at the University of Not- offers so much more: there is a large you can be reassured that there’s tingham, UK, all of whom feature in assortment of miscellaneous chemis- something here for teachers and the videos. The team is led by Martin try-related videos. One of my favour- students of all the sciences. For Poliakoff, who has a very distinc- ites is ‘Perfect perfume’, in which example, the site has a link enti- tive, relaxed and engaging camera the team try to create the ultimate tled ‘sixty symbols’ that leads to presence. Other members of the Valentine’s Day scent. Others cover short video clips about the symbols team include lecturers who present topics ranging from the pesticide DDT used in physics and astronomy. their own specialities, such as Pete to dynamite and Viagra® – and the There is also a link to the Foodskey Licence with his explosive practical ‘elements song’ is an excellent piece of website, about the science behind demonstrations; technicians; a public comedy! There is even a set of vid- what we eat and drink. And the awareness scientist; and Brady Haran, eos on road trips that the team have molecular videos feature a range of a video journalist with a passion for taken to parts of the UK, Europe and well-known drugs such as aspirin, science communication, who is also beyond. For example, during a trip to morphine and salbutamol. the creator of the website. With this Turin in Italy, they produced a video Importantly, all of the videos are wealth of expertise, it is no surprise on the chemistry of the Turin shroud short, engaging and interactive. My that the team has created such a and radioactive carbon dating. colleagues and I use them to trigger marvellous resource for teachers and The Periodic Table of Videos is a discussions on specific topics, but students. As well as via their website work in progress; new videos are also just for general interest. The Pe- and on Youtube, you can follow the constantly being added, and the ele- riodic Table of Videos was a difficult team on Facebook and Twitter and by ments videos are updated as the team website to review because I just kept RSS feed. Brady Haran also has a blog sees fit. One recent update was to the going back to watch one more video. with links to his photos on the online carbon video: to include more infor- I defy you not to become entranced photo repository, Flickr. mation on allotropes and the wonder- by these clips! The Periodic Table of Videos links ful Nobel prize-winning material,

Science in School I Issue 24 : Autumn 2012 www.scienceinschool.org Reviews Chemistry

graphene. The website is an example Resources of the way students should be engag- The Elements of the Periodic Table ing with science. No textbook could website, developed by the UK’s ever capture the imagination in the Open University, enables visitors way these presenters do. They also to explore the impact of chemical have the facilities and experience to elements on our bodies and the demonstrate experiments that would world around us, and see how their not be possible in a school laboratory. discovery changed the course of

The latest video I watched was history. See: www.open.edu or use Image courtesy of NikNaks; image source: Wikimedia Commons filmed on Martin Poliakoff’s birthday. the direct link: http://tinyurl.com/ He visited the Nottingham Nano- d4levwb technology and Nanoscience Centre, If you found this review interesting, where one of the researchers there why not browse all the reviews took a hair from Martin’s head and in Science in School? See: beamed a stream of electrons onto www.scienceinschool.org/reviews it, creating a microscopic lithograph of the periodic table on the hair. Just one more wonder of modern science and technology, and just one more imaginative video on this marvellous, highly recommended website. Do visit it and experience it for yourself. Details URL: www.periodicvideos.com

Web references w1 – The forerunner of the Periodic Table of Videos website, the Test Tube website, hosts a wide range of videos about the world of science. See: www.test-tube.org.uk w2 – Nottingham was designated a ‘science city’ by the UK government in 2005. See: www.science-city.co.uk

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