HWJSHarvard-Westlake Journal of Science • Issue 1 • spring 2007
Revolutionizing Air Hockey FINDING a CURE FOR HPV 5 Things that will BOGGLE your mind
PLUS: Q & A with Dr. Nassar HWJournal of Science CONTENTS Academic Research Articles 26 5 Photovoltaic Cells 8 Electromagnetic Air Hockey 9 Hydrogen Vehicles 10 Frequency Distribution and Ciphers 12 Cosmic Microwave Background Radiation 16 Zic1 in Lamprey 20 Acoustic Refrigeration Features 4 Meet the Doctor: Q & A with Dr. Antonio Nassar 21 Cartoons 24 Taking Technology to a New Level: 9 INSPIRE Microwave Interferometer 25 A Coast-to-Coast Search for the HPV Vaccine The Importance of Fun & Curiosity in Research Nobel Prize Winners in Science 26 New Inventions of 2006 Five Things That Will Reprinted with permission of students in the Furman University Boggle Your Mind Environment and Society class, 2005
Cover: the sun in ultraviolet from NASA Back: Munger Science Center by Allen Miller See page 22 >>
Matt Kremer, Marc Firestein, and Jerry Porter Cameron Lazaroff-Puck Allen Miller and Justin Chow
0 2 spring 2007 photographs by Eliza Eddison, Allen Miller, and Emiliano Rios From the Editors HWJS Founders & Editors-in-Chief: Justin Chow & Allen Miller
Faculty Mentors: Dr. Antonio Nassar Kathy Neumeyer
Research Editors: Michael Casey Elizabeth Eddison Marc Firestein Starting Adam Gold Carlee Joe-Wong a Legacy Matthew Kremer Zachary Mirman Allen Miller and Justin Chow Sarah Park Since the merger in 1991, Harvard-Westlake has built one of the greatest high school Gerald Porter level science programs in the nation. Our school offers 22 science courses—with every- Alfredo Ramirez thing from Astronomy to Geology to A.P. Physics C: Electricity and Magnetism. Our cam- Charles Sheng pus is home to the amazing physical resource of Munger Science Center—a building filled Benjamin Uy with state of the art equipment. We have talented and experienced teachers who annually Madeline Young help us top the nation in Advanced Placement exams while also cultivating imagination and discovery. At Harvard-Westlake we have a sense of pride towards our academic repu- Feature Editors: tation and tradition of excellence. It is with this tradition of excellence in mind that we Albert Chen now cross a major milestone and proudly bring to you the first ever Harvard-Westlake Justin Chow Journal of Science. Leland Farmer When we first sat down to plan out the journal all we had was a faint idea of what we Jeffrey Hartsough hoped to accomplish, wild imaginations and an empty folder we hoped to fill—nothing Brian Ko more. In fact, from that day forth, we believed that it was our imaginations coupled with Matthew Kremer the energy and dedication of each staff member that allowed us, more than anything else, Cameron Lazaroff-Puck to reach the point where you can now touch and read a tangible manuscript of what we Allen Miller had in mind all along. Nevertheless, our inexperience was an obstacle at times. On more Gerald Porter than one occasion, one of us would comment to the other, “How are we going to pull Charles Sheng this off?” The general response to such mutually felt moments of helplessness would be, Gordon Wintrob “Well, I guess we’ll just have to start with the basics.” And so we did. Photo Editors: Early on, we both knew that we wanted the journal to appeal to the scientific com- David Alpert munity (i.e. students interested in science or research, faculty members in the science de- Justin Chow partment and the administration). Yet, we wanted the journal to be broader in its appeal Elizabeth Eddison or more inclusive in its audience range. We wanted any person who happened to pick up Allen Miller a copy of the journal to be able to find something of interest in it. With this in mind, we Andrew Miller began the long journey toward the production of the journal—a journey that would not Emiliano Rios be possible without the commitment of each staff member. With this first issue, which was created, managed, and edited entirely by students at Cartoon Editors: Harvard-Westlake, we hope to have accomplished these goals. In the journal you will find Zachary Mirman conventional academic-style research articles in the first section. However, if you seek Gerald Porter humor, flip over to our cartoons page. For the scoop on new inventions and developing technology, have a look at our page on technological progress in 2006. These sections and Layout Editors: many more are available for your enjoyment and intellectual fulfillment. We hope that Adam Gold this publication will generate within each of you an unquenchable curiosity in the physical Marsha Labunsky and natural world. Yet, ultimately, we hope to inspire you to continue the Harvard-West- lake tradition of excellence! Contributing Designers: Justin Chow Allen Miller Justin Chow Allen Miller ([email protected]) ([email protected]) Harvard-Westlake Journal of Science 3700 Coldwater Canyon Los Angeles, CA 91604 www.hwscience.com/HWJS/index.html photographs by Andrew Miller spring 2007 0 3 Meet the Doctor Ten years ago, Dr. Antonio Nassar was mentoring a casual after-school scientific research activity for a few students when he realized the potential growth the genuine scientific interest exhibited by the small group could produce. Three years later, Nassar created what is now known as Directed Studies: Scientific Research (DSSR). Along with the scientific research club, DSSR encourages hands-on applications of scientific concepts spanning fields from astrophysics to game theory. We caught up with the mastermind of DSSR to find out more about him. Dr. Antonio Nassar Q+A: Dr. Antonio Nassar talks to the editors about his life, his work, science, and DSSR. In the Life of Dr. Nassar… Education Q: What was it like growing up in Q: What was your most recent Brazil? accomplishment? • B.S. Electrical Engineering and Physics, Brazil A: I had a pretty good life, and from A: I just had my 42nd scientific • M.A. Physics, UCLA an early age I was very curious about article published in a major journal • Ph.D. Physics, UCLA (1992) science. I liked to put together plastic of physics. The article was entitled Teaching Experience cars, ships and planes that my father “Schrödinger Equation for an • 20 years of experience on bought for me. Extended Electron.” General Physics (13 years teaching Physics 6A, B, and C at Q: Did your family have a role in Q: Who do you consider to be your UCLA), Electronics, and Physics shaping your scientific life? most prominent scientific hero? of Sound and Acoustics (17 years A: My father had a large building A: I read many books written by Isaac teaching at Harvard-Westlake company that built, among other Asimov and Arthur C. Clark, loved School) things, fifteen high-rise buildings science fiction movies such as 2001: A Publications (about sixteen stories each) in my Space Odyssey and Star Trek. But the • American Journal of Physics, hometown. Such influences as these greatest scientific figure in my life was Journal of Optics B: Quantum fostered a great desire in me to Richard Feynman. and Semiclassical Optics, Nuovo become an engineer. Cimento, The Physics Teacher, Q: Current work? Physical Review Q: What do you like to do for fun? Awards and Honors A: I’m working on an application of • UCLA Physics Department A: I have fun doing research on the quantum theory I’ve developed for physics and staying home or going out an extended electron. I hope to carry Teaching Assistantship award with my wife and daughters. out quantum tunneling calculations (1981-1986; 1987- 1988) using this new formalism. • Letter of recognition for Q: How successful do you think accomplishments in teaching DSSR has become? Q: What is your take on the future and research from Governor Pete of DSSR? Wilson (January 31, 1991). A: It has grown enormously. I started • Harvard-Westlake School Justin with four students the first year, six in A: I’m sure DSSR will inspire a lot of Rascoff Teaching Award the second and now we have eighteen students to become greater scientists. • MIT nomination and recognition students enrolled. We will have It will definitely leave a lasting for excellent teaching about twenty-eight students next impression on all the students who year. The success can be measured experience the course. Just ask any • INTEL Science Talent Search - by the interest and enthusiasm DSSR student for their perspective Teacher of Merit demonstrated by the students. about the impact on their lives.
For more information, visit Dr. Nassar’s website at www.physicsland.com. 0 4 spring 2007 photograph by Justin Chow Research Articles
Using the sun as a source of energy has been tried by many different people. Both the ancient Greeks and Romans used it passively to light and heat in- door spaces. Many others have con- structed machines that use solar energy. One of the earliest people to do so is Auguste Mouchout, a nineteenth-century inventor. Concerned about France’s de- pendence on coal and fossil fuels, Mouchout created a steam engine solely powered by the sun. His first experiment used a glass-enclosed iron cauldron that trapped the sun’s rays as they passed through the glass cover. The heat from the rays caused the water in the cauldron to boil and form steam. Because the amount of steam was so little, Mouchout added a reflector to his setup that concentrated more radi- ation onto the cauldron, generating a greater amount of steam, enough to power a small steam engine. Around the same time, William Adams created a setup of seventy- two flat mirrors arranged in a semi- circle that would track the sun’s movements. In testing this appa- ratus, he placed a piece of wood in the focus of the mirrors, causing the piece of wood to immediately ignite. Beginning his work in refrigera- tion, which eventually led to the de- sign of the first non-reflecting solar motor, Charles Tellier used an appa- Bright ideas ratus similar to the flat-plate collec- tors designed by William Adams to The importance and implementation of photovoltaic cells heat water. Using ammonia instead of water to power his apparatus, By Michael Casey, Sarah Park, Alfredo Ramirez and Maddy Young since ammonia’s boiling point is sig- nificantly lower, Tellier was able to » photograph by Lars Sundström spring 2007 0 5 Therefore, silicon must turn light into power and to improve the effi- A B C find four more elec- ciency of existing solar technologies. trons with which it can A new development in solar cell research is bond. the triple junction solar cell. Traditional solar Atoms of phospho- cells operate by absorbing light of a certain rous have one more va- wavelength. This limits the amount of energy lence electron than at- that can be absorbed by the cell. To make a tri- oms of silicon, so there ple junction solar cell, various semi-conducting will be one extra elec- materials are layered on top of each other. The tron from the phos- result is a three-layer solar cell. The top layer phorous with which absorbs one color of light, while the middle no other electron will absorbs another color of light, and the bottom Figure 2: (A) Boron, (B) Phosphorus and (C) Silicon bond. When light another color. This method allows for about some device with solar cells, we define the 2√(Pdeli)rInt / Emf√(Rload). Figure 3 strikes such an appa- 41% efficiency solar cells, doubling the effi- load resistance R (Figure 3) as the resistance Because the values of ySeries and xParal- power a water pump in his well at a rate of about ratus, the electron, because it repels the other ciency of standard solar cells. Cells like these that the said device exerts in the circuit. As lel may not necessarily be whole numbers as three hundred gallons per hour during daylight. electrons, leaves freely. The portion of the cell are predicted to be out on the market within charges flow through the device, their electric calculated, we considered several worst case Swedish engineer John Ericsson invented that has atoms of phosphorous, or other group twelve months. However, multi-junction cells potential decreases. Of concern is the wiring of scenario issues with rounding the values up an innovative method for collecting solar rays V elements, is called N-type silicon. are very expensive, at $40/cm². the solar cells in a circuit to deliver the maxi- or down by .5. Our analysis was made assum- in the form of the parabolic trough. Unlike a P-type silicon, on the other hand, is the A new coating has been produced that in- mum amount of power to the load resistance, ing an unlimited quantity of solar cells, but Figure 3 real parabola that focuses radiation on a single portion of the cell that has impurities such as creases the efficiency of older solar cells by re- i.e. to match the power required for the given real world constraints may complicate this. We focal point, the parabolic trough focused the atoms of boron, or other group three elements ducing the reflection of sunlight. By reducing load resistance. We must not send an amount think that, for a given number of solar cells, we sun’s rays in a line across the open side of the of the periodic table (those with three valence the reflected sunlight, a higher concentration larger than required; e.g. if you send too much must configure the circuit to achieve as high a reflector. Trying to solve problems in the tele- electrons). Because boron only has three elec- of sunlight is absorbed by the solar cell, in- power to a light bulb, it will burn out. This task value on the original Pdelivered curve as pos- phone system of Bell Laboratories, scientists trons, there are “holes” where the electrons of creasing the power output of the cell. Layering is roughly on the same level as optimization sible, but further investigation is needed. Gerald Pearson, Daryl Chapin, and Calvin Fuller silicon want to join with other electrons. These various materials, gradually decreasing the in- problems from algebra II or calculus: given a set Because ySeries for the optimum setup de- developed the first silicon solar cell that could holes, because they represent an absence of an dex of refraction between each layer, produces of constraints, find a way to maximize a speci- pends inversely on the Emf of the solar cell, if generate a measurable electric current. After electron, make the “extra electrons” from the the coating. This layering results in a reflection fied quantity. The quantity power P is given by the power delivered and load resistance values building a solid-state rectifier of lithium-gal- N-type silicon move towards this side of the of as little as .01%, increasing solar cell output the formula P = ε2R/(R+r)2. When this curve are rather large compared to the Emf, ySeries lium silicon, an appliance that converts direct apparatus. by 5% to 10%. is graphed, as P in terms of R, a curve arises will be very large. We found that for our 1V current to alternating current, Pearson, Chap- By themselves, N-type and P-type silicon similar with a definite maximum at the specific solar cells and the goal of powering a normal in, and Fuller found, to their surprise, that the are electrically neutral. There is no large move- References load resistance of R*. It can be shown using household appliance, the setup would be im- Figure 4 rectifier created a significant electrical flow. ment of electrons, and the number of protons http://www.scientificamerican.com calculus that the value of R* that achieves this practical, requiring hundreds of solar cells. tors between them to equate those resistances in each atom matches the number of electrons maximum power is when R* = R = r. in the hopes of powering the motor better us- References for that atom. When the N-type and P-type Wiring Solar Cells to Obtain Maximum Further Topics of Inquiry and Research ing the given solar panel. www.eoearth.org/article/Mouchout,_Auguste http://www.motherearthnews.com/Alternative-Energy/1975-11-01/A-Genu silicon are placed in contact with one another, Power Transfer Finding the Setup for Maximum Power One problem is taking into account real We attempted to measure the internal resis- ine-1870-Solar-Powered-Steam-Engine.aspx http://www.solarenergy.com/info_history.html however, the free electrons move from the N- Below we present a method for wiring solar Transfer world constraints such as the aforementioned tance of one of our 1V solar cells for a given light www.cs.ntu.edu.au/.../sid101/solar1/Smith.html www.nndb.com/people/731/000095446/ to the P-type silicon. The “holes” move from cells of a given internal resistance in a grid pat- We assume that we have no prior con- maximum number of solar cells. We still have source, but we kept finding rather high internal www.goldmine-elec-products.com/images/G13153B.jpg the P-type to N-type side. The place where this tern so as to transfer maximum power to a load straints on the number of solar cells we can use to investigate if this will affect our current ap- resistance values. We learned from article 2 www.bell-labs.com/blimages/home/anniversary50.jpg http://southface.org/solar/solar-roadmap/solar_how-to/history-of-solar.htm occurs is called the junction. resistance. We also discuss further topics that and that they all have the same electromotive proach significantly. Another real world issue given to us by Dr. J. Perreault that measuring After a certain point, equilibrium is achieved we shall be researching in this field. force Emf and internal resistance rInt. We also would be if one or several of the solar cells or the internal resistance is not a straightforward How a Solar Cell Works and an electric field is formed. Because this An important consideration that must be take the power required by the load and the re- their connections shorted or broke; we could task; there is an actual maximum power point A solar cell is generally made out of silicon. equilibrium exists, it is harder for the electrons taken into account when using solar cells to sistance of the load Rload as given. Our circuit investigate if there are ways to mitigate the loss for the solar cell itself, and the internal resis- On the surface, an anti-reflective coating is to move across from the N-type to the P-type power any device is that solar cells in a general is then set up as in Figure 4, with ySeries rep- of the solar cell on the overall circuit because tance for a solar cell changes non-linearly de- used to block the reflection of light. Silicon is side. Now electrons can only truly travel from sense act like real batteries. They can be mod- resenting the number of solar cells in series per the broken solar cell will act as a higher resis- pending on the light intensity. Two methods shiny, and therefore tends to reflect light easily. the P-type to the N-type side. As a result, this eled as consisting of a source of electromotive column and xParallel representing the number tance than rInt. There may be ways to make were presented to find this maximum power For the solar cell to be most efficient, it needs junction acts as a diode. force and an internal resistance . of columns in parallel. the circuit still work fairly well at this degraded point, one using harmonics and one using a to capture the most sunlight. Thus this coating When photons from the sun strike the cell, One can think of the electromotive force We can make a grid of (ySeries)(xParallel) level, such as bypassing that specific cell, etc. recursive method; we need to determine which is used to attain maximum efficiency. the electron flow is once more disrupted as as a charge pump: as charges flow through the solar cells act as one large solar cell with an An option that we have now is to construct a we shall use for our measurements. We also When sunlight strikes the cell, electrons are electrons absorb energy from the photons. The circuit, they are brought from a lower electric equivalent resistance Rload even if rInt does small electronics-scale type circuit using small would like to better quantify the performance able to move freely about in the circuit. With electrons will now move from the P-type side potential to a higher electric potential as they not equal Rload already. The solar cells put in light bulbs with the goal of showing that the of the solar cell, given the light intensity and the N-type and P-type semiconductors present, to the N-type side. The “holes” will move to the pass from the negative to the positive termi- series, the ones in each column i.e. one behind brightness of the bulb does indeed depend on temperature, so as to better calculate the inter- a current can be created and electricity can be P-type side from the N-type side. At this point, nals of the battery. A charge carrier at a higher the other, essentially increase the equivalent the arrangement of the grid of the small elec- nal resistance in terms of those quantities. generated. electrons will want to move to the P-type side, potential has the ability to do more work than a resistance of that column from rInt. Putting tromotive force solar cells we have. We have We would also like to define an efficiency re- The cell is composed of a semiconductor ma- which is what happens before sunlight strikes charge carrier at a lower potential. The electric the columns in parallel, i.e. side by side, essen- done some preliminary tests with various ar- garding this problem; we would like to quantify terial (again, usually silicon) with impurities of the cell. Electrons will flow and generate a cur- potential is analogous to the height on a hill at tially decreases the equivalent resistance of the rangements of ten solar cells and an LED and how below the maximum power for the grid ef- other elements, such as boron and phospho- rent. The electric field will be accountable for which a tank of water is stored. The higher the equivalent large solar cell from the equivalent have verified that there is a noticeable differ- fects the performance of the load. This efficien- rous. These impurities are integral to the func- the voltage created by the cell. potential, the greater the energy of the water resistance of each column. ence. We now plan to quantify and document cy quantity could then help us determine how tion of the photovoltaic cell; without them, no when it reaches the bottom of the hill; the en- Through our calculations we showed that this data using more controlled conditions, to operate under the constraints of a specified current could exist and electricity would not be References ergy this water has can then be used to power the optimum setup is defined by: Pdelivered = because the intensity of the light and the tem- number of solar cells. How necessary is it for us http://www.howstuffworks.com 2 2 2 generated. http://www.pv.unsw.edu.au/images/future-students/solar-cell_p-n.jpg) a waterwheel for some application. A resistor (Emf RloadxParallel ySeries ) / (RloadxParallel perature in the environment effect the opera- to operate with matching resistances? The silicon atom has four valence elec- http://www.webelements.com having an internal resistance indicates that + RIntySeries)2 where Pdelivered is equal to the tion of the solar cell. Also, given the large solar trons—or electrons in the outermost orbital of there is a resistance to the flow of charge in the power required by the load. cell that powers the donated fan we received, References 1. Raymond A. Serway, and John W. Jewett, Jr.. Physics for Scientists and En- the atom—whereas atoms of boron have three, Current Research by Other Organizations circuit at the battery; the electrons cannot flow Because the net internal resistance must we could find if the manufacturers matched the gineers. Belmont, CA: Brooks/Cole-Thomson Learning, 2004. 2. U.S. Department of Energy, Energy Efficiency and Renewable Energy, Solar and atoms of phosphorous have five. Each Inefficiency is a major problem in solar cells. freely through the battery without exerting equal the load resistance, (Rload)(xParallel) internal resistance of the solar panel to the load Energies. Technologies Program. 2005. 15 March 2007
0 6 spring 2007 spring 2007 0 7 is fairly simple, but applying it to achieve our goal was a little bit more complicated. A solenoid is a tube of material with a large number of tightly wound coils of wire around Fuel for thought it, with two ends through which to run direct Understanding hydrogen vehicles current. There exists a known relationship between electric current and the magnetic
field a solenoid creates: B=μonI, where μo is the permittivity of free space constant, n is the By Matt Kremer and Marc Firestein number of turns per unit length, and I is the current. However, there was a major issue with Hydrogen vehicles run on hydrogen fuel our plan: solenoids create this field primarily cells, the concept of which was first discovered by inside of the tube, and the field outside Christian Friedrich Schonbien in 1838. Five years diminishes rapidly with respect to distance. There was a solution, however. By placing later, the first rudimentary fuel cell was made a ferromagnetic bar (a bar that can be by Sir William Robert Grove. However, fuel cells were not put to impor- magnetized) inside the solenoid, the magnetic tant use until the space age, when they were used to produce both elec- field inside the solenoid magnetizes the bar. tricity and water on space shuttles. It was not until very recently that Figure 1 The bar, then, acts as a standard magnet, thus fuel cells were first produced commercially by United Technologies. extending the field beyond the solenoid. Since There are four major components to the basic hydrogen vehicle (Fig. For example, a tank of hydrogen will last for a distance comparable to a switch can stop and start the current at will, 1). First is the fuel tank (1), which holds compressed pure hydrogen, ei- a tank of gasoline, whereas pure electric vehicles have a much shorter we can also stop and start the magnetic field ther in liquid or gaseous form. Second is the fuel cell stack (2), which is range before they need to be recharged. when desired. equivalent to the internal combustion engine in a gasoline vehicle. There With such positive attributes helping to fix critical global problems, One problem not yet encountered that is are anywhere between 150 and 200 fuel cells stacked together in order one might ask why hydrogen vehicles are not being commercially pro- possible occurs from the fact that ferromagnetic to obtain enough power to make the vehicle run. The electricity trav- duced. The answer is that hydrogen vehicles cannot yet be produced cost materials will eventually maintain some els to the third component, an electric motor (3), which converts the efficiently; for example, the Honda FCX, which has minimal features be- magnetism. However, fixing this problem electricity to the mechanical energy that propels the vehicle. The final yond those of a basic car, has a production cost of over $100,000. Hy- would simply require replacing the bars. component is a battery pack (4), which acts similarly in some ways to the drogen vehicles are expensive because hydrogen cells are expensive, for
engine in a hybrid vehicle. Part of the electricity from the fuel cell stack two main reasons. First, hydrogen cell materials, especially the polymer The Design is stored in the battery to be released when rapid acceleration and extra membrane, and production processes are expensive because of the com- The table on which the game is played, built power are desired. plicated nature of fuel cells. Single fuel cells are not cheap as is, and a with the help of Max Gindi, is a combination of Hydrogen cells create electricity by capturing the energy released in single vehicle needs 150 to 200 medium size cells to have enough power acrylic and wood. A 24” by 36” plate of 0.25” the exothermic chemical reaction: 2H2 + O2 => 2H2O to run. Further, the fuel efficiency of hydrogen cells decreases as power thick acrylic rests upon a wooden frame. The Hydrogen atoms consist of one electron and one proton. The fuel increases. Thus the cost of increasing the potential power output of the frame, supporting the perimeter of the plate, cell splits these at the anode. The protons are then able to pass through fuel cell stack, and therefore increasing the horsepower of the vehicle, is raised by four 12” high legs. A wooden a polymer membrane to the cathode. The electrons cannot pass through becomes increasingly multiplied with each additional desired horsepow- perimeter also exists on the top of the plate to and travel through a wire to the cathode, creating an electrical current. er. In addition, hydrogen cells are extremely fragile, and, if hit in an ac- keep the ball in play, with two 7” wide holes in Hydrogen vehicles have many positive attributes which make them cident, would be easily destroyed; thus necessary protection compounds this perimeter serving as goals. appealing to society, which is why so much research is being done in an the issue of expense. In our plan, the solenoids rest just attempt to make them affordable to consumers. First, hydrogen power Another major engineering issue that is critical to the hydrogen car is underneath the table; however, this poses is completely clean; its only emission is pure water, so it does not harm safety. Hydrogen cars presently run on highly pressurized hydrogen gas two questions: how do we move the solenoids the environment at all. Also, hydrogen cars are more practical than other mounted in canisters. If the canisters crack in an accident, or through naturally, and how do we make a system alternative energy vehicles being researched or already on the market. ordinary wear and tear, the ensuing combustion from the dispersed that allows for free flowing play? After trial Game time hydrogen could cause a large, invisible fire, a property and error, we found with solutions for both Taking air hockey to a new level of hydrogen-heavy combustion. In addition, the rush of issues. By using mechanical joysticks that hydrogen from a tank with a pressure of 5000 psi could attach to the electromagnets and run through push a car far off of the road, leading to other obviously a ball joint, and on which the entire circuit is By Marc Firestein, Matt Kremer and Jerry Porter R negative outcomes. contained, the electromagnets can move in two One potential solution could improve the existing dimensions smoothly. These joysticks are PVC Electromagnetic “air hockey” consists of an acrylic table, model: electrolysis. This process utilizes electricity to split pipe that extend as far as one needs to move water into hydrogen and oxygen, which would be stored electromagnets, and a metallic sphere. Utilizing the ability to switch the electromagnet. Then, by using momentary in somewhat smaller, safer tanks. The hydrogen cell stack push button switches, the current can be circuits on and off at will and the properties of electromagnetic would recombine the two and convert the chemical en- turned on and off by holding down the switch. ergy to mechanical energy. Refueling would be similar to induction, we can create and control magnetic fields. We can Imagine a joystick with a trigger; if the trigger that of an electric vehicle. The vehicle would be plugged is held down, the current runs, but once the thus move a sphere in a game that also resembles foosball. in to an electric source to perform the refueling process trigger is released, the current stops. of electrolysis; however, certain drawbacks of the elec- of magnets in them. This enlightened us to the Our current design gives each player one Introduction tric vehicle, such as necessity for frequent charging and We were intrigued by the possibilities that power of creating magnetic fields with switches. electromagnet joystick, which is constrained reduced power, would be eliminated. Furthermore, using switches in circuits present. The application of Being big players of table sports games, we to movement on that player’s half of the table pure oxygen instead of air would increase the efficiency switches is quite powerful; the ability to control came up with our game: Electromagnetic “Air to prevent collisions. However, changes in the of the cell. current opens up a world of possibilities. Hockey.” number, strength, and configuration of the While the hydrogen car seems to have quite a few posi- We considered combining circuits and electromagnets could improve gameplay. Our tive values, its drawbacks seem to make it a dangerous, in- electromagnetism when we began a side table is a prototype, but improvements are The Physics efficient model. Nevertheless, possibilities like electroly- investigation experimenting with solenoids and This project, more than anything, tested definitely possible. Maybe a project for a 2008 sis and advances made in the last generation point to this the lowest energy potentials of combinations our ability to engineer the model. The physics DSSR student? Figure 2 style of power being the future of vehicular movement. 0 8 spring 2007 photograph by Matt Kremer spring 2007 0 9 Figure 1: 13 Greatest Percent Frequencies in Descending Order Sample 1 0.114 0.0677 0.0609 0.0609 0.0582 0.0582 0.0568 0.0528 0.0487 0.0419 0.0352 0.0284 0.0244 Sample 2 0.135 0.0805 0.0725 0.0725 0.0692 0.0692 0.0676 0.0628 0.0580 0.0499 0.0419 0.0338 0.0290 Sample 3 0.111 0.0705 0.0690 0.0564 0.0549 0.0533 0.0533 0.0439 0.0360 0.0329 0.0282 0.0266 0.0266 Sample 4 0.120 0.0957 0.0855 0.0841 0.0812 0.0797 0.0638 0.0565 0.0522 0.0435 0.0333 0.0333 0.0275 Zeroes and ones Sample 5 0.133 0.0844 0.0793 0.0793 0.0793 0.0639 0.0614 0.0512 0.0460 0.0409 0.0332 0.0332 0.0332 Frequency distributions and ciphers Sample 6 0.139 0.0854 0.0784 0.0756 0.0728 0.0672 0.0658 0.0616 0.0602 0.0462 0.0420 0.0294 0.0252 Sample 7 0.100 0.0952 0.0940 0.0879 0.0842 0.0781 0.0635 0.0501 0.0464 0.0440 0.0403 0.0317 0.0317 Sample 8 0.119 0.0883 0.0834 0.0761 0.0736 0.0699 0.0650 0.0650 0.0552 0.0540 0.0344 0.0307 0.0307 Sample 9 0.137 0.0953 0.0913 0.0819 0.0725 0.0685 0.0617 0.0523 0.0456 0.0430 0.0403 0.0349 0.0349 Sample 10 0.104 0.100 0.0905 0.0865 0.0689 0.0676 0.0608 0.0541 0.0514 0.0473 0.0324 0.0324 0.0284 By Carlee Joe-Wong letter, is 93.3% of 0.740. Thus, most samples of text appear to have fairly uniform frequency Figure 2: 13 Lowest Percent Frequencies in Descending Order Monoalphabetic substitution ciphers are predecessors distributions overall. Sample 1 0.0203 0.0176 0.0176 0.0162 0.0162 0.0135 0.0135 0.0108 0.00541 0.00135 0 0 0 The general uniformity of frequency Sample 2 0.0242 0.0209 0.0209 0.0193 0.0193 0.0161 0.0161 0.0129 0.00644 0.00161 0 0 0 of enciphering messages by replacing each letter with another, Sample 3 0.0251 0.0219 0.0219 0.0157 0.0141 0.0141 0.0125 0.0094 0.00627 0.00470 0 0 0 distributions partially carries over to individual Sample 4 0.0261 0.0217 0.0188 0.0188 0.0159 0.0159 0.0101 0.0101 0.00435 0.00145 0 0 0 often using some kind of algorithm. This turns a coherent message, frequencies; the FD between two letters of the Sample 5 0.0307 0.0281 0.0281 0.0205 0.0153 0.0153 0.0128 0.0128 0.0102 0.00512 0.00256 0 0 Sample 6 0.0252 0.0238 0.0224 0.0182 0.0154 0.0140 0.0126 0.0084 0.00420 0.00420 0.00140 0.00140 0 called the plaintext, into the ciphertext, which means nothing same relative frequency is generally similar to Sample 7 0.0305 0.0220 0.0183 0.0159 0.0159 0.0122 0.0122 0.0122 0.00855 0.00244 0.00122 0.00122 0 the average FD, especially in letters of lower Sample 8 0.0270 0.0221 0.0209 0.0196 0.0172 0.0135 0.0123 0.0110 0.00736 0.00245 0.00123 0 0 unless the reader converts the ciphertext back to the plaintext. Sample 9 0.0268 0.0228 0.0161 0.0161 0.0134 0.0121 0.0107 0.0094 0.00805 0.00134 0.00134 0.00134 0.00134 frequency. The maximum FD between the Sample 10 0.0257 0.0243 0.0230 0.0216 0.0203 0.0149 0.0135 0.0122 0.0108 0.00405 0.00270 0.00135 0.00135 Ideally, only the intended recipient can perform this conversion; letters of any two samples is 0.049, between the most frequent letters in samples 7 and 14. Figure 3: Letters in Descending Order of Frequency however, almost all monoalphabetic ciphers percent frequencies from each other, the The FDs between letters of the thirteen lowest Sample 1 E N I O A L S T H D R U G C F Y BPKMWVQJXZ can be solved without knowledge of the second greatest percent frequencies from each frequencies, however, are more reasonable; the Sample 2 E N I O A L S T H D R U G C F Y BPKMWVQJXZ Sample 3 E S A T N I O H R L C MUD G PVB Y F WKXJQZ enciphering algorithm. other, etc.) to find the frequency distribution, maximum is 0.0144. However, these large FDs Sample 4 E T N I S O H A R L C F DUPM Y G WBVKJQXZ Over the years, cryptanalysts have or FD. The absolute values of these differences were clearly moderated by the other letters in Sample 5 E A I N T O S L R P F H U C BDM G WV Y KXZJQ Sample 6 E O A I S N T R L H D C PWMUVB F Y G KXJQZ established a fairly systematic method of were then added to obtain the total frequency the text samples, since the maximum average Sample 7 E N A S I T O R D H L C G UMPW Y BKV F QJXZ decipherment that relies on frequency analysis. difference (total FD), a number representing FD per letter found between two samples was Sample 8 E T A O H S I N R DMLU C Y P F W G VBKXJQZ Figure 4: Total Frequency Difference Between Samples (z) After computing the frequency of each letter in the variation in overall frequency distribution only 0.0098. The average maximumF D between Sample 9 E T I N A S O H R C LDU G F BMV Y WPZJKQX Sample 10 E T A I O N H L R S DWU C M G F Y BPVKJQXZ as a Function of Sample Number (x, y) the ciphertext, the cryptanalyst compares these between the two samples of text. letters of the thirteen greatest frequencies is frequencies to the known average frequencies This analysis yielded a set of three hundred 0.280; it is 0.00946. Thus, though frequencies and “valleys” representing extremely high and the same number of times, and “G” and “P” frequency distributions, which is in fact the of letters in English writing and thus identifies, total FDs, whose values are plotted on the vary widely among individual letters, especially low total FDs respectively. One can see that combined make up 24% of the elements in case. This principle is extremely useful in at least tentatively, the plaintext letters that three-dimensional plot shown in Figure 4. among the letters of greater frequency, the several of the “peaks” occur in a straight line, the column. In some columns five or even six deciphering polyalphabetic ciphertexts; it correspond to the ciphertext ones. While The numbers of the two texts are the x- and y- overall frequency distributions between when the y-value is held constant. This value letters appear more than twice and up to seven allows the use of frequency distributions to this method is extremely useful in starting to values and the total frequency difference is the two samples of text are in general relatively is 19, and the occurrence of so many peaks at letters more than once. While even seven is determine the number of alphabets used in guess letter identities, letter frequencies vary, z-value, ranging from approximately 0.0651 to consistent. y=19 visually demonstrates that sample 19 is significantly less than the twenty-six letters of polyalphabetic encipherment. and the degree of their variation is obviously about 0.255 with a mean value of 0.128. Thus, Because of the relatively large range of total responsible for several of the largest total FDs. the alphabet, showing that there are definite relevant to a cryptanalyst using frequency the average FD per letter between two samples FDs, I then analyzed the ten pairs of texts with Most of the “valleys,” however, or the lowest trends for a certain letter’s relative frequency, Explanation of Figures analysis. In this paper, I examine the degree of text, calculated between letters of the same the greatest and the ten pairs of texts with the total FDs, seem to be spread throughout the there are clearly too many letter possibilities for Figures 1 and 2 represent the 13 greatest and of frequency distribution variation between graph, just as the lowest total FDs come from a a cryptanalyst to rely completely on frequency least percent frequencies yielded by all twenty- different samples of text, and conclude from wide range of samples. The graph also supports analysis in deciphering a message. five samples respectively, sorted in descending my analysis that monoalphabetic frequency my conclusion that frequency distributions are order from left to right. Each row represents a distributions are in general quite uniform. relatively uniform, since most of the z-values, Conclusion: Other Applications different sample. Thus, the number in [8,9] of However, individual frequecies and the letters There are clearly too many letter or total FDs, appear to be around 0.15 or less. As stated above, overall frequency Figure 1 represents the ninth-greatest percent corresponding to the relative frequencies (most distributions, provided letter identities are frequency of any letter in sample 8. In Figure frequent, second most frequent, etc.) can vary possibilities for a cryptanalyst to rely Direct Application to Cryptanalysis: not considered, are fairly uniform in two 2, the number in [8,9] represents the twenty- a good deal. Letter Analysis given samples of plaintext or monoalphabetic second greatest percent frequency in sample completely on frequency analysis. Although a study of the variation in total ciphertexts (if they are sufficiently long). This 8. The zeros at the end of Figure 2 represent General Method frequency distribution between samples of principle is particularly useful in another area of all letters that do not occur in a given sample. Before any analysis could be performed, text is interesting to a cryptanalyst, it becomes cryptanalysis, solving polyalphabetic Vigenère Figure 3 contains the letters corresponding to samples of text had to be gathered from a variety useful only when frequencies of individual ciphers. The general method of Vigenère Figures 1 and 2. For example, the H in [3,8] of sources to generate twenty-five unique text relative frequencies, is only 0.128/26, or least total FDs to determine whether specific letters are analyzed. Comparison of the letters encipherment is to encipher every nth letter of Figure 3 means that H’s percent frequency samples, which were then numbered from 1 0.00491. Because the relative frequencies are samples of text caused the abnormal results. in each column of Figure 3 should give a good with a different sequence of letters, where n = in sample 3 is given by the number in [3,8] of to 25, with at least three-hundred and fifty being subtracted from each other to obtain the Text samples 2, 14, 19, and 24 occurred at least indication of frequency analysis’ accuracy; 1,2,3…x and x is the length of a chosen keyword. Figure 1. All letters with a 0% frequency are characters. The occurrences of all twenty- total FD, varying frequencies can be ignored twice in the pairs of text with the greatest total for example, if one letter is almost always the Thus, the frequency distribution of a Vigenère listed in alphabetical order from left to right at six letters in each sample were found using a in calculating the average FD; the difference FDs, with 19 by far the most common, occurring most frequent, a cryptanalyst could reasonably ciphertext, or in fact any polyalphabetic the end of the row in Figure 3. program in Maple and divided by the number between the largest frequencies and between 35% of the time. Since sample 19 therefore assume that the most frequent letter in a given ciphertext, would look very different from one Figure 4 is a three-dimensional graph shown of characters in each sample after discarding smallest frequencies should be of the same caused 70% of the abnormally high total FDs, ciphertext represents that letter. This is in fact generated by a monoalphabetic cipher, since at an angle. The total FD is the z-value and the numerals, spaces, and punctuation, to get general magnitude. Admittedly, the greatest one can probably assume that, in general, total the case; in 24 samples of text, “E” is the most one cipher letter would represent n plain letters samples that yielded a particular total FD are each letter’s percent frequency. The matrices total FD, produced by samples 14 and 19, is FDs are not as pronounced as, for instance, frequent letter. instead of just one plain letter. The general the x- and y-values. For example, the z-value at in Figures 1-3 show the resulting data up to more than twice the mean total FD at 0.255, 0.255, from samples 19 and 14. The ten least The results become somewhat more varied uniformity of monoalphabetic frequency x=3, y=4 is the total FD from the comparison of sample 10 (see “Explanation of Figures.”) which yields a relatively high 0.00981 average total FDs were produced by fourteen samples in the next columns; while “T” is generally the distributions would thus allow a cryptanalyst samples 3 and 4. Since comparing two identical FD per letter. However, this is a fairly isolated in all, indicating that these lesser total FDs are 2nd most frequent letter, “A” and “O” combined to determine whether a ciphertext is poly- or text samples yields a total FD of 0, the z-values Percent Frequency Analysis value, and irregularities should be expected not caused by texts with abnormal frequency make up 28% of the elements in the second monoalphabetic, a very useful distinction since along the line x=y are all zero. In addition, the To investigate the overall difference in from a sample of only twenty-five texts. distributions. Thus, frequency distributions column of Figure 3. This increased diversity deciphering polyalphabetic ciphertexts is very graph on one side of x=y is a reflection of itself 1 total frequency distribution between samples, 0.00981 is also significantly less than (1– /26 may well be more uniform than indicated in the of letters continues and increases slightly different from deciphering monoalphabetic on the other side. Therefore,I have only shown 25 percent frequencies of each sample are + /26)/26 = 0.0740, the maximum possible previous paragraph. throughout the other columns. For example, ciphertexts. The uniformity of monoalphabetic the z-values on one side of x=y to provide compared to every other sample’s by subtracting average FD per letter; in fact, 0.00981 is 86.7% The graph in Figure 4 clearly shows the wide in the 13th column of Figure 3, the two most ciphers also suggests that ciphertexts using a greater visual clarity. On the other side of the the relative percent frequencies (the greatest of 0.740 and 0.00491, the average FD per range of total FDs in my data, with “peaks” common letters, “U” and “F,” occur almost given number of alphabets have fairly uniform line x=y, the z-values are shown as 0.
1 0 spring 2007 spring 2007 1 1 ble, working at the Mount Wilson Observatory Hoyle, it accepted universal expansion but Wilson, working with Bell Labs, had also built in Pasadena. His work involved the concept of found a way to keep the universe static. Al- a powerful radiometer, though they wanted to redshift. though the universe clearly was expanding, the use it to conduct satellite communication ex- Redshift is quite literally, the shifting of theory suggested that perhaps small quantities periments. However, their instrument had a electromagnetic radiation, typically visible of matter would also be continually formed, so small hiss in all directions that made it impos- light, toward the red end of the spectrum as the overall density of the universe would re- sible for them to conduct their experiments, an it travels from the source to the observer. This main constant. In so doing, they could happily excess 3.5 K antenna temperature that would will occur when an object is moving away from conclude that the universe has always looked not go away. Penzias and Wilson thought it the observer as it emits light, similar to the the same as it does today, and it will always was perhaps due to pigeons trying to roost in Doppler effect, because the waves of light get look that way. Due to the rate of expansion, the the antenna, and they went to great lengths lengthened and thus appear redder. (However, amount of matter that would have to be con- to remove them. But the pigeons weren’t the if the wavelength is already longer than red, stantly created would be small enough that we answer. They had discovered theC osmic Micro- redshifting will actually move it further away would not have to detect it. wave Background, as they and Dickie began to from red.) A redshift can also occur because the Though they were proven wrong, the Steady realize over the phone. Penzias and Wilson won space itself through which the light travels is State theorists actually helped another branch the Nobel Prize in 1978. expanding, which has a similar lengthening ef- of astronomy. With only Hydrogen, Deuterium, The proponents of the steady-state model fect. Helium and lithium they needed a source for countered that the radiation might be com- Hubble noticed that spectra of light coming heavier elements, as fusion in normal stars can ing from modern day sources, but, as repeated from galaxies and other distant astronomical only create elements as heavy as Oxygen. They measurements of the CMBR showed it to be ex- objects appeared to be redshifted from what helped show that supernovae could a source for tremely uniform, these arguments were proven would be expected in laboratory conditions. heavy elements, which eventually became an false. Universal expansion soon became the This led him to conclude that there is a force aspect of the Big Bang theory as well. most widely accepted theory in cosmology. moving galaxies (and by extension all objects) While the Steady State theory showed prom- So where exactly does the radiation come away from us. Since there was a direct correla- ise at the time of its inception, it didn’t last from? Remember that as we look out into the tion between the galaxy’s distance and its red- very long. Quasars were first discovered in the night sky, it is as though we are looking back in shift, data suggested an isotropic, (remember, late 1950s and had been conclusively shown by time. Since light only travels at 3 x 10^8 meters the same in all directions) metric expansion. the 1960s to only be found at extreme redshift. per second, the farther the light has to travel That is, the speed at which distant galaxies were This suggested, along with other evidence, that to reach our eyes, the longer ago it started its moving away from us was proportional to their there was such thing as an “early” universe, one journey. We can only see back so far into the distance, otherwise known as Hubble’s Law. which looked very different from how it does universe, up to a finite distance called the ho- Hubble explained that the reason objects within our galaxy are not themselves expand- ing (in fact, the stars in the galaxy are not even moving apart from each other, which is why A brief history of space they are not really redshifted) is because objects Even Einstein, the greatest physicist of Finding answers in the cosmic microwave background radiation within a galaxy are gravitationally bound—for them, the strength of gravity overpowers the the 20th century, was unsettled by the *Adapted from a lecture given February 2007 strength of expansion. Thus, expansion can be though of simply as an increase in the space be- concept of a universe that wasn’t static. tween galaxies. By Adam Gold tific method, viewed heavenly bodies as perfect Hubble’s findings gave weight to the bur- substances made of imperishable aether. Stars geoning Big Bang Theory, first proposed by a German astronomer Heinrich Wilhelm Olbers formu- and planets were neither created nor destroyed, number of physicists during the twenties. If the lated a paradox in 1823 that followed a long line of astronomical moving according to well-defined principles. universe is currently expanding, and there is no today. rizon length—past the horizon length it would Newton, too, believed that on a large scale, the evidence of it having ever contracted, then we But the best evidence in favor of the big bang take light from those objects more time to trav- thought. If the universe is infinite, as we assume it to be, then why is universe must be static, and he also believed it can follow that expansion backwards in time theory was about to arrive. In 1948, the same el to our eyes than the history of the universe. the sky dark? If the universe is truly infinite, than every possible line was largely the same everywhere, irregardless to an early universe that must have once been years the steady state theory was proposed, a The farthest we can see back into the uni- of direction. The word scientists use for such at an extremely high temperature, density and group of physicists had predicted that the base verse is called the surface of last scattering, and of sight in the night sky should end on the surface of a star. It can be independence of direction is “isotropic.” pressure. temperature of vacuum in the universe was it is also the starting point of all CMB radiation shown that if we were to draw a series of spheres around the earth, Even Einstein, the greatest physicist of the Of course, the Big Bang theory does not ex- above absolute zero, due to energy left over we observe. Before about 380,000 after the 20th century, was unsettled by the concept of plain what happened before this. Many scien- from the big bang. The proposal was largely start of the universe, everything was hot plas- each sphere, containing a certain number of Kepler believed the paradox was the foun- a universe that was not static. In his theory of tists have given their opinions, ranging from a ignored until the 1960s, when it was rediscov- ma, a nearly uniform cosmic soup of charged stars on it, would add the same amount of light dation of an argument for a finite universe, general relativity, was unhappy with his field gravitational singularity to God. Furthermore, ered by Robert Dickie and Yakov Zel’Dovich. In particles and photons. Radiation pressure kept to our sky. An infinite sum of spheres would or at least a finite observable universe, and equations because they would not lead to a the idea of a Big Bang was hard for some people 1964, several of Dickie’s colleagues at Princ- mass from coalescing into denser chunks due mean a sky that was not only bright but infi- he was only partly right. One of the most ba- static universe. So, he added a cosmological to swallow. If the universe had a beginning, it eton, David Todd Wilkinson and Peter Roll, de- to gravity, as it does today. Temperatures were nitely so. Yet the night sky, even when there are sic concepts in Cosmology is universal expan- constant (literally the energy density of a vacu- likely also had an end. The most common theo- cided to try to build a very powerful microwave so great, in fact, that electrons did not bind to no clouds, is mostly dark. Another explanation sion. That is, about 13.7 billion years ago, the um) to the equations in order to force the uni- ry today about the ultimate fate of the universe detector (they called it a Dickie radiometer) to atoms, and energy was not absorbed by mat- might involve cosmic dust or other particles universe was extremely dense and hot and has verse to be static. Of course, he later called it is called the “Big Freeze,” in which the universe see if the universe really was filled with radia- ter as it is today but scattered, or re-emitted (non-stars) that exist in the universe and block been expanding and cooling ever since. Why do the “biggest blunder” of his life. His equations keeps expanding, cooling all the while, until it tion just above absolute zero. If there was this in a random direction, bouncing around the out the light, explaining why most of what we we think this is true? had been right all along, and he didn’t need the is too cold to support life. Other theories have remnant of the big bang that filled all of space, clumps of plasma. But when the temperature see is darkness. But thermodynamics states It is a very radical idea, to think the universe cosmological constant. equally unsavory names such as the “Big Rip” there was not any reason that they would not of the universe cooled enough that atoms were that nothing can continue to absorb radiation expands. Students today learn it in elementary But even around the time of Einstein’s or the “Big Crunch.” be able to detect it. formed, a process called recombination, the en- without eventually having to re-emit it. So this school, but for most of human history, nearly greatest discoveries, there was growing evi- One way of getting rid of that pesky end Before the Princeton experiment yielded ergy was no longer scattered and continued to cosmic dust could only act as an intermediary all scientists have believed the universe, at dence that the universe did indeed change over that no one wanted to really think about was results, Dickie received a phone call from Craw- travel in the same direction as when it was last between the stars and our eyeballs. Clearly this least once it was created, was static. The Greek time. Some of the first observational evidence the Steady State Theory. Proposed in 1948 by ford Hill in nearby Holmdel Township, New scattered, cooling with the expansion of the was not the answer. scientist Aristotle, to whom we owe the scien- to support expansion came from Edwin Hub- Hermann Bondi, Thomas Gold, and Sir Fred Jersey. Arno Penzias and Robert Woodrow universe. »
1 2 spring 2007 images from NASA and the WMAP Science Team spring 2007 1 3 From the point of view of an observer, the surface of last scattering can be thought of as a sphere encircling that position at horizon length. We cannot see past the surface of last scattering the same way that we can’t see sky through the clouds—because past the surface of last scattering (and therefore before the sur- face of last scattering) the universe was opaque to radiation. Of course, to answer the question of when the photons of the CMB themselves were origi- nally formed, you have to go even earlier back in time. In the first few seconds, temperatures were so extreme that particles and anti-par- ticles were constantly being created and anni- hilated, with each annihilation creating lots of energy. However, once the temperature cooled enough so that the particles and anti-particles could not be created again from the energy, the energy was “stuck” in the universe, and it has been traveling and through it ever since, cool- ing with the expansion of the universe. We know today that the Cosmic Microwave Background Radiation is uniform to 1 part in 100,000 and is extremely cold, comparable to This graph is a measure of the angular power spectrum as measured by WMAP from I = the radiation emitted by a body at about 2.73 2 to I = 1000. The measured data is shown in black. degrees Kelvin. Why so cold? As the universe has expanded and the radiation has been red- is going on? One proposes that maybe there is If the universe is positively curved, meaning shifted, it gets cooler and cooler, and will con- an invisible force pushing them together. The that the mass density of space is large enough tinue to do so as the universe continues to ex- other says that no force is needed; their situa- to “close” the universe like a sphere, the force pand. When it was first released, 380,000 years tion can be easily understood if the surface of of gravity will be great enough to cause the after the big bang, it was at a temperature of the earth is curved. Before we praise the second universe to recollapse: the “Big Crunch.” Or, if about 3,000 K, which at about 4,090 degrees as a visionary, let us consider our own ways of the mass density is too low, the universe will F, is pretty toasty. The CMBR is so uniform, in viewing the universe. We believe in an invis- be hyperbolic in shape, and expansion will ex- fact, that temperature differences in it can only ible force called gravity that pushes objects pand forever. CMB analysis has shown the uni- be detected outside our atmosphere. together, but this “force” could also be simply verse to be very close to flat—meaning that it Even if the planet was not encased in at- understood, as Einstein pointed out, if we sim- will continue to expand but asymptotically ap- mosphere, it would be impossible to “see” the ply accept that space-time itself is curved. That proach zero. CMBR on the planets surface. The photons is, as we pursue an ostensibly straight course Of course, new research suggests the curva- have been redshifted to the point that they through space and time, matter causes a dis- ture may not be a good indicator of the fate of are below the visible spectrum of light and are tortion that curves the path we take so that we the universe after all, since expansion appears microwaves, around the same length as radio move towards it. to be accelerating for reasons scientists don’t and TV waves. In fact, about 1% of the static While we can think of matter curving spa- understand. The term “dark” energy refers to you used to be able to see between TV channels cetime in the local sense, scientists also won- the energy that is driving this acceleration, before the age of cable was from the CMBR. If der whether our universe is globally curved. with the term “dark” referring to the fact that humans could see light in the microwave range, One way they can find out is by studying the we can’t seem to find it. the night sky would appear to be bathed in a background. Cold spots on the background rep- Another one of the many insights gleaned faint but extremely uniform glow in every di- resent areas of greater mass way back when, from the CMBR is a partial resolution to the rection. The photons are arriving at a rate of because it would take more energy for the horizon problem. We talked earlier of a horizon 10 trillion photons per second per square cen- photons to escape these gravity wells on their length—the farthest we can see based on the timeter. way to our detectors. The hot and cold spots age of the universe. But if we follow that hori- So what does the CMBR get us? Well, one in the early universe can actually be thought zon sphere backwards in time, growing smaller application is to help discover the curvature of of as sound waves—with the hot spots being and smaller, as we look for the origin of ob- the universe. What does it mean for space-time compressions and the cold spots being rarefac- served structures, the horizon eventually gets to be curved? Well, here is an example. Two tions. Back then, all was plasma, so compres- smaller than the structure itself. Therefore, people living at the equator decide that they sion waves traveled through the universe like nothing can explain how the different parts of The top picture shows an overview of the microwave sky, where the yellow, red and salmon areas indicate an especially strong ga- are tired of the heat and the rain and want to sound does through air. Since the background the structure are causally connected. Unless, of lactic foreground signal. The lower picture is a full-sky map of the W-Band (94 GHz), giving a relatively complete picture of the CMBR move somewhere cooler and drier. Not having preserves things as they were a very long time course, we turn to inflationary theory, which without much galactic foreground (shown in red). Both pictures were constructed by the WMAP Science Team using data from WMAP. traveled much, they both immediately decide ago, we can compare the size of these cold spots posits that, shortly after the big bang, a new on the North Pole. They start off 100 feet apart (the actual size) to the sizes of present day ob- form of energy caused a brief, massive expan- from each other and walk north, traveling in servable objects in space. The larger the curva- sion of the universe—inflation. And inflation, triggered at the same time, only possible if the One explanation for why the sky is dark at each successive “sphere” of stars around the perfectly straight lines. They are quite sur- ture of the universe, the smaller the spots on as far-fetched as it seems, is supported by universe began so small that it was causally night is that the universe has only been around earth would contribute less light (and not the prised to find that they migrate closer and clos- the CMB will appear relative to the observed analysis of the CMBR. Remember the “sound connected in the moments immediately after for a finite amount of time. Light from stars same amount as we predicted earlier), because er to each other as they approach the pole, and objects, because the universe acts like a lens. waves” in the plasma of the early universe? Ob- the big bang. that are an infinite distance away hasn’t yet radiation from farther objects is redshifted they collide just as they reach it, even though Why is curvature important? Because the servations show that the waves, the primary So what about Olber’s paradox? Did we had time to reach us. more, and thus brought down to a lower energy both were walking completely straight. What curvature of the universe determines its fate. sources of variation in the universe, were all solve it yet? Astronomical redshift also suggests that state.
1 4 spring 2007 spring 2007 1 5 typically studied as model organisms for neu- ral crest investigations. Because the hagfish embryos (the only other jawless vertebrate group) are unobtainable, the lamprey presents a unique model to study the evolution of the neural crest in vertebrates. Determining when gene mechanisms re- sponsible for crest formation evolved is es- sential for determining how neural crest was invented and how it has been conserved dur- Post fert 2 cell stage 6.5 hrs 4 cell stage 11.5 hrs Blastula 24 hrs ing evolution. The presence of a common neu- ral crest gene network in extant lampreys and higher vertebrates would suggest the presence of those mechanisms in the common ancestor of the agnathans (jawless) and gnathostomes (jawed). Lampreys have most neural crest de- rivatives but lack some in the trunk (sympa- thetic nervous system) and in the head (jaws). The fact that many of the genes found in Xeno- pus at early stages of neural crest development are also present in lampreys (personal commu- 2 day 3 day 4 day 5 day nication with mentor) suggests conservation of the neural crest gene network between gna- thostomes and lamprey. Neural crest cells are multipotent neuroec- todermal cells originating at the neural plate border between the neural and non-neural ectoderm (1,6,9). Neural crest cells undergo a change of shape from epithelial to mesenchy- mal cells and emigrate from the dorsal aspect of neural tube extensively throughout the em- bryo according to well-established pathways 6 day 8 day 10 day 12 day (9). They finally settle and differentiate into a Figure 3: Cell cycle of lamprey embryos starting from post-fertilization to the 12 day stage larva. plethora of derivatives such as cranial cartilage, pigment cells and the elements of peripheral nervous system (3,6). rion lifts after fertilization (confirming that border territory. During the 5th day, the neu- ral and non-neural ectoderm at 4 days of de- Another way of defining neural crest cells the embryo has been fertilized) protecting the ral precursors begin to come together forming velopment (Figure 4). By 5 days expression is involves the expression of neural crest specific embryo from hyper spermiation which causes a bulge. On the 6th day, when the neural tube found in the dorso-lateral aspect of the neural genes. Zic1, the knockout target of this experi- more than one developmental signal to be forms by a secondary cavitation, neural crest rod and at 6 days in the dorsal part of the neu- Undersea ment, and the Msx1/2 and Pax3/7 family mem- produced. The development of lamprey em- cells begin to migrate from the dorsal aspect. ral tube and the developing somites. This ex- bers are early markers of the neural plate bor- bryos can be seen in Figure 3. Approximately On the 8th day, the neural tube formation is pression pattern is similar to Zic1 expression der territory. Their expression makes the neural 6 hours after fertilization, the embryos begin completed. At 7.5-8days, the pre-hatching em- in Xenopus embryos during comparable devel- plate border territory competent to respond to to undergo the first furrow and divide into two bryos begin to twitch. At 9 days, secretion of opmental stages. evolution subsequent neural crest inducing signals and cells at approximately 6.5 hours. At this point, hatching enzyme occurs helping to digest the defines the identity of that territory. Ca2+ deposits are used by the centromeres to chorion. By the 10th day, most of the embryos Zic1 Protein Knock-down in Lamprey The role of Zic1 transcription factor in neural In Xenopus, Zic1 is implicated in the regula- facilitate cell division. The internal cellular use have successfully hatched out of their chorion We performed the protein knockdown of crest development in lamprey tion of neural induction and in the patterning of Ca2+ causes the embryo to separate from and begin to move freely on their own. On the Zic1 gene, using anti-sense morpholino oli- of the neural plate border. In early Xenopus surrounding substrate, in this experiment at 12th day, heart and heart activity are observed gonucleotides, a method previously used in By Benji Uy neurula, Zic1 and Pax3 are expressed in the the bottom of a crystallizing dish. As the de- (7). higher vertebrate model organism embryos border between neural and non-neural ecto- velopment progresses, the cells undergo fur- to study gene function. We used translation- A characteristic trait of vertebrates is the presence derm (neural plate border), as well as the neu- ther cleavage steps and continue to divide (7). The Expression of Zic1 in Lamprey blocking morpholino designed to complement of neural crests at early embryonic stages. These migratory cells ral territory. Depletion of the Zic1 protein in After 24 hours, the embryo is at the blastula Zic1 is expressed in the neural precursors, the target sequence on the Zic1 messenger Xenopus embryos, using morpholino antisense stage, having the shape of a hollow ball of cells. as well as in the border territory between neu- RNA, positioned upstream and encompassing » contribute to important developmental structures in vertebrates. oligonucleotide injections, results in failure of Gastrulation starts 3 days post fertilization. Vertebrate chordates are the earliest phylum in which neural crest crest formation (4,5). Monitoring of this phase is critical because, if In this study, we have identified the lamprey an embryo dies, it secretes a toxin which kills migration is found. Chordates are characterized by a notochord, Zic1 homolog to patterning in Xenopus. Ex- surrounding embryos. Thus during the gastru- a rod-like supporting structure that develops sidered to have provided the tools for their pression analysis and morpholino knockdown lation period, constant manual dispersion of underneath the neural tube. Non-vertebrate predatory lifestyle, such as a strong cranial of this gene in lamprey embryos show that, as embryos and monitoring is required. Gastrula- chordates, such as cephalochordates (amphi- structure, denticles, and a peripheral nervous in Xenopus, this gene functions in the pattern- tion continues until the beginning of the 4th oxus) and urochordates (ascidians) are filter system with new bilateral sensory organs. ing of the neural plate border and therefore day. On the 4th day, primary neurulation be- feeders and predate vertebrates. They lack Lampreys are basal jawless vertebrates plays a role in neural crest formation. gins. The neural plate begins to condense rath- a complex, vertebrate-like brain and do not whose lineage diverged from jawed vertebrates er than roll into a neural tube like in other ver- have neural crest cells or neurogenic placodes approximately 500 million years ago. Jawed Results and Discussion tebrates. At this time, border specifiers such as (6). Thus, the “invention” of neural crest cells vertebrates (gnathostomes) such as chick, frog Lamprey embryos develop more slowly Zic1, a zinc finger protein, are present in these 4 day 5 day 6.5 day is attributed to early vertebrates and is con- and mouse appeared later in evolution and are than average vertebrate embryos. The cho- early pre-migratory stages in the neural plate Figure 4: Zic1 expression in lamprey embryo as visualized by in sito hybridization.
1 6 spring 2007 photographs by Benji Uy spring 2007 1 7
A B Figure 9: 12 day lamprey, dorsal root gan- Figure 8: (A) Control side. (B) Zic1 injected side. glia expression in the presence of SoxE1 probes. Conclusion gonucleotide against lamprey Zic1 gene (Zic1 The neural plate border specifier Zic1 is MO; 5’-CGCCTCCAGAAGCATCGCGTGCGGT- A B C expressed in the lamprey border territory in 3’), was injected into a single blastomere at the a similar manner to the Zic1 expression pat- two-cell stage and at 5 days of development, Figure 5: (A) Embryos injected at the 2 cell stage with FITC labeled Morphalino antisense oligonucleotides. The cells have undergone tern in Xenopus. Furthermore, as in jawed the embryos with unilateral integration of the their first division and are starting the second division. (B) The pico-spritser used to inject and deliver mopholino into the cells. (C) 6 day vertebrates, Zic1 inactivation seems to affect morpholino were pre-selected using fluores- embryo pre-selected for unilateral distribution of the morpholino. proper neural crest formation, inhibits expres- cence microscope. Embryos are then fixed us- sion of neural crest markers and causes long- ing in MEMFA (MOPS/EGTA/MgCl2 salts and term defect in neural crest derivatives. Thus, 4% formaldehyde), and dehydrated to 100% the translation start site (ATG codon). Rather and AP-2 is missing on the Zic1-depleted side the role of Zic1 in the neural crest development methanol and kept at -20ºC. than a 5’ ribose member ring and anionic phos- of experimental embryos suggesting that, as in appears conserved in lamprey, a basal jawless phates, morphalino antisense oligonucleotides Xenopus, Zic1 is essential for the proper neu- vertebrate, suggesting that this portion of In Situ Hybridizations have a 6-member morpholine ring and non- ral crest formation and the expression of these the regulatory network was invented prior to Prior to in situ hybridization procedure, the ionic phosphorodiamedates (2). The binding markers. The expansion of the neural tissue of divergence between jawless and jawed verte- embryos are re-hydrated to 1xPBS and decho- of the morpholino is specific to corresponding the injected side, shown by the widened Pax3/7 brates and that Zic1 was probably utilized in rionated. DIG labeled antisense RNA probes mRNA and mechanically obstructs translation expression domain, suggests that as in the case the ancestral vertebrate. against the genes of interest in this study were of the protein. By injecting the lamprey em- of neural plate border genes in Xenopus (Msx1 synthesized according to the standard proce- bryos with these anti-sense oligonucleotides, and Pax3; [4]), Zic1 may be involved in the pat- Animal Care dures. In situ hybridization was performed ac- translation of the protein is inhibited. More terning of this neural plate border territory. Adult mature and maturing lampreys were cording to previously described standard pro- precisely, these antisense oligonucleotides When the Zic1 protein is depleted, the undif- obtained from Hammond Bay Biological Sta- cedures (8). After the in situs were completed, are designed to bind to complementary bases ferentiated neural crest identity of this ter- tion, Michigan. Since lampreys usually die pictures were taken in 75% glycerol/PBS. on mRNA just upstream or encompassing the ritory is lost and possibly replaced by specific after they mate, the mature female and males translation start site. neural function. The neural crest markers are are kept at 12ºC in order to slow down the de- References Baker, C., & Schlosser, G. (2005). Editorial: The evolution origin of neural crest We injected fluorescent labeled Zic1 mor- lost and neural crests fail to form properly. composition process and increase the number and placodes. Zoological Science, 5, 109-118. Gene Tools.”Gene Tools, LLC - Morpholino Antisense Oligos From Gene Tools: pholinos into a single blastomere at the 2-cell of fertilizations possible. The number of eggs Superior Technology, Comprehensi.” Gene Tools. 25 Aug.-Sept. 2006
1 8 spring 2007 spring 2007 1 9 Keeping their cool Two seniors tackle acoustic refrigeration
Setup We made a Plexiglas tube-and-box setup for the experiment. The base was 16.4 cm x 16.6 cm x 11.0 cm, and the tube is 25.4 cm high with an inner diameter of 2.5 cm. We drilled four holes into the base in a square pattern in order to affix the speaker in the base with screws. We created a thermocouple, a temperature sensor that can be used to convert thermal potential difference into electric potential difference, by soldering two copper and one constantan wire together and affixing the two unattached copper ends to a voltmeter. After experimenting with this thermocouple, we found that, though it worked, its level of accuracy was well below what we required for our experiment. We then ordered the Omega Thermometer HH66R, which accommodates Types K/J/T/E/R/S/N thermocouples (though we only are working with type K). We filed the ceramic stack down to the appropriate diameter for the tube, at a size able to be moved if thus required but not when unwanted. We filed down two equal By Eliza Eddison and Zack Mirman semi-circles in the base of the apparatus to feed the positive and negative leads in to affix Acoustic Refrigeration is a process that produces a temperature to the speaker while maximizing closure and gradient through the resonance of standing sound waves. Sound waves therefore efficiency of the system. We added a rubber lining to the top of the tube where the in a resonating chamber set up standing waves at certain frequencies. aluminum plug is inserted in order to tighten This experiment should provide a relationship between frequency, the seal and prevent heat loss. After we placed the leads for the thermocouple above and below voltage and temperature. Voltage, as measured by thermocouples, the stack, we hooked up the thermometer to a will be compared to the variable frequency created by the speaker. computer to read the output of the data.
A basic concept in physics is that of the In our recreation of the experiment, we Next Steps standing wave in a resonating chamber. Sound modified and replaced various pieces of the We are now ready to begin taking data waves from a fixed source at certain frequencies apparatus. The main difference is the stack, points. Our two variables are the height of the fall into a set pattern (in effect, “stand”). This which in the original experiment design was ceramic stack in the tube and the frequency is the same phenomenon that occurs when made of fishing wire pasted vertically on a piece of the sound emitted from the speaker. Using a finger plucks the string of an instrument, of photographic film. This was then tightly the simple formula: v = fλ, relating velocity though the sound waves in this experiment wound together and lowered into the tube. to frequency of wave and the wavelength in have no linear medium to pass through and, We replaced it with a ceramic stack with two-dimensional systems, we have calculated as such, are invisible. This experiment was first many small holes in close proximity. The a range of frequencies to test for the resonant published in the American Journal of Physics in ceramic stack has been shown to increase the frequency. These frequencies are between 373 December of 2002 by Dan Russell and Pontus temperature gradient more efficiently and and 746 Hz. We will test for the other variable Weibull. The experiment yielded a 46 degree is better built than the film tightly wound by moving the stack down and up in set Fahrenheit temperature gradient across a stack around pasted wire. The actual apparatus was increments for every frequency using a string made of film and wire. In this open-closed recreated in very similar dimensions to the and needle system we rigged on the stack to pull system, the formula for the wavelength at the original acoustic refrigerator. We also added it up, and a broad based pusher to gently push first harmonic is 4L=λ with L representing a means to tighten the seal on the tube to it down. We will then plot the data points on length of tube. Two copper and constantan make the aluminum plug more effective. We graphs and calculate the optimal intersection thermocouples were created and placed above are seeking the same theoretical point as the of stack placement and wave frequency. and below the stack. The system was closed on original experiment: a pressure maximum and Once this intersection is found, we can test the top with an aluminum plug. The speaker a particle displacement minimum. However, smaller increments of frequency and placement was screwed onto the Plexiglas box-shaped we believe that it will be different given the within this range in order to find the absolute base of the apparatus, facing upwards into the three dimensional nature of the waves that maximum temperature gradient which can be tube, and attached to a frequency generator were considered to be two dimensional in the produced in our thermoacoustic refrigerator. equipped with oscilloscope. original experiment.
2 0 spring 2007 photograph by Justin Chow SCIENCE SMILES
The ol’ Chicken Crossing the Road By Jerry Porter
Be Practical By Zack Mirman
spring 2007 2 1 This year in DSSR... 20 seniors researched 10 scientific topics ranging from acoustic refrigeration to acne-causing hormones during Dr. Nassar’s 3rd period class. Adam Gold Exploring Cosmic Microwave Background Allen Miller and Justin Chow Radiation The Role of Hormones in Acne
Matthew Kremer, Marc Firestein and Jerry Porter Lizzie Sparks Electromagnetic “Air Hockey” and CO2 Lasers: The Applications of Hydrogen Fuel Cells Benji Uy and Charles Sheng Industrial Examining the Genes Technology Zack Mirman and Eliza Eddison in Worms for Cutting and Welding The Use of Sound Waves in Refrigeration
Albert Chen, Leland Farmer and Brian Ko Evanescent Waves and Cameron Lazeroff-Puck Microwave Interferometry The Exploration of Circuitry and Very Low Frequency Transmissions
Michael Casey, Sarah Park, Alfredo Ramirez and Madeline Young Maximizing the Efficiency of Solar Cells Dani Kudrow The Uses of Thermonic Valves in Amplification 2 2 spring 2007 photographs by Justin Chow, Eliza Eddison, Allen Miller and Emiliano Rios spring 2007 2 3 Cameron Lazaroff-Puck INSPIRE
By Cameron Lazaroff-Puck
Leland Farmer, Albert Chen and Brian Ko INSPIRE is an acronym which stands for the “Interactive NASA Space Physics Ionosphere Radio Experiments.” Beginning in 1990, the INSPIRE Project has monitored very low frequency (VLF) radio signals which occur Taking tech in the earth’s magnetosphere. These signals can be manmade as in the case of the LORAN navigation system transmissions or can occur in natural phenomenon such as lightning. These VLF signals are audible on any AM radio to a new level as static. Radio signals in the VLF range (0-50 kHz) 2 projects use cutting-edge have the property that their propagation is heavily affected by both the ionosphere and technology to run experiments the magnetosphere. When lightning strikes, high energy bursts of radio waves are created in we placed two foil-covered plates next to each addition to the obvious visual flash of light. The Microwave other with an open slit in the middle to allow behavior of these VLF waves of radio energy microwaves to pass through only through the can yield valuable information about the Interferometers opening. atmosphere, ionosphere and magnetosphere Based on diffraction we expect to be able to which extends tens of thousands of kilometers receive a strong signal from the transmitter at By Albert Chen, Leland Farmer into space. every few degrees as the transmitter is rotated First, the VLF receiver must be constructed. and Brian Ko and a weak signal in between the strong sig- Early on in the year, a VLF-3 kit was purchased nals. To demonstrate the microwave tunneling and I subsequently assembled it, attaching Our group spent most of the year develop- effect, which shows that microwaves can pass all the needed switches, capacitors, resistors, ing a microwave interferometer setup that al- out of a prism and back into it, we used a block diodes and inductors. The receiver was then lows us to conduct various experiments using a of triangular plastic with the transmitter and fitted with a suitable antenna. After all the microwave receiver/transmitter. receiver perpendicular to each other. The waves parts were assembled, the reciever was then Interfermoters are important because they should enter the prism and internally reflect to ready for testing. can be used to explore certain classical and the receiver, but the signal should be weaker When using the reciever, one must wait quantum physics effects such as interference, because the waves have shifted slightly so that until nightfall and listen through a set of diffraction, microwave tunneling, standing the receiver does not pick up the entire trans- headphones. The most common naturally waves, etc. but on a larger scale (longer wave- mission. occurring VLF signals, whistlers, produced length than light gives easier measurement). We have recorded data for standing waves, mostly by intracloud and return-path lightning The basic setup consists of a microwave diffraction, and interference, and are still tak- strikes, sound very similar to a slide whistle. transmitter and receiver facing each other and ing down data for the microwave tunneling ef- There is also the possibility of observing another an open space in the center where objects can fect. The data is still undergoing analysis, and rarer phenomenon around the time of sunrise, be placed to affect the reception of the signal we are currently trying to match the results of referred to as a dawn chorus. A database of from the transmitter. The receiver can be ro- the experiments to known quantum physics ef- these VLF signals collected by students and tated to change the angle between the receiver fects. enthusiasts is kept by NASA in their attempt to and transmitter. In the diffraction experiment, catalog this phenomenon. 2 4 spring 2007 photographs by Eliza Eddison The Importance of Creativity in Research paper twisted once By Jerry Porter and scissors. Unfor- In the beginning, I selected my project out tunately, the simplic- of pure curiosity. I was playing with my water ity ends with cutting Jerry Porter bottle wrapper in English class, twisting and strips of paper in half cutting it and noticing the various resulting and becomes more complicated as I draw the when I am done. loops. resulting loops, noting the number of inter- After several days of experimenting, I was When I returned to class the next day and locked resulting loops, number of twists, and certain that I had solved the problem. I wrote mentioned my discovery to Dr. Nassar, he the many topographical shapes. The difficulty equations for the number of shapes, number of thought that there might be something of in- with the topographical shapes is that there are loops, and number of twists until it was discov- terest in the strips as, when they were flattened many ways to flatten a strip of twisted paper. ered that the shapes were all the same. against the table, they created a topographical At first I believed I had discovered four In the future, I have to determine how many map of the strip. Dr. Nassar hypothesized that shapes: a figure eight, a bow, a box, and what more shapes the strips can be flattened into. I there was a relationship between the topo- I called a tooth. Later, when playing with the also need to find out whether it is possible to graphical map of the strip and the stable state shapes, I discovered that they are all basically neatly flatten sixteen strips to create some new of atoms or elementary particles. the same. The tooth can be rearranged into a stable pattern. Ultimately, I need to know what The research I am conducting is on the much box, the bow in a figure eight. This duplicity is do the topographical maps mean? simpler side because all I start with is a piece of the exciting part of my research; I never know A Coast-to-Coast Search for the HPV Vaccine School of Public Health linked four-month experimental trial at By Charles Sheng HPV-16 and HPV-18 with 99.7% JHMI, saw the lesions eliminated I had the pleasure of seeing a of all cervical cancers. Because completely. While it is of course presentation from a key clinical of this link, cervical cancer could better to prevent the lesions from developer of the Human Papilloma ostensibly be vaccinated against, ever occurring, this does provide a Virus vaccine: Dr. Cornelia Trimble given that a vaccine for HPV was last-resort option for those already at Johns Hopkins University in not entirely out of the realm of affected. November. In the United States, possibility. The vaccine took 25 However, the success of Gardasil malignant neoplasm of the cervix, years to fully develop, but the has been limited by government generally known as cervical cancer, results were beyond expectations. and social objections and is a causes 4,000 deaths a year, about Gardasil, produced by Merck, has prime example of the obstacles 1% of all cancer deaths. However, an extremely high success rate and medical advances in the United worldwide cervical cancer causes a very low amount of blowback, States face. In several, mostly 200,000 deaths and is the second the gold standard of safe vaccines southern states, the promotion most prevalent form of cancer in (the smallpox vaccine, for instance, and distribution of the vaccine has women. is not widely distributed because been limited by the belief on the However, cervical cancer is now it infects the patient more often part of parents that immunity to almost completely preventable. than is acceptable). an STD will make their daughters There are many different strains of Furthermore, the vaccine has more promiscuous. In this country HPV. Most aren’t dangerous, but been shown in early clinical trials of limited public healthcare and two strains, HPV-16 and HPV-18, to work retroactively. Patients who a powerful religious lobby, not cause cancer. A report published had high-grade dyslpasia and had much has been done to change in 1973 by the Johns Hopkins presented lesions, treated with a their views. Justin Sheng This year’s nobel prize winners in scientific fields: Prize in Who What Why It Matters Physics John C. Mather They helped discover the anisotropy of the cosmic It helped to cement the big bang theory. and George F. microwave background radiation and its similarity Smoot to an ideal blackbody. Chemistry Roger D. Kornberg He studied the molecular basis of eukaryotic It defined an exact process by which RNA is created. transcription. Physiology/Medicine Andrew Fire and They discovered RNA interference-gene silencing by It showed that RNA plays an important role in the Craig C. Mello double-standed DNA. regulation of the flow of gene information. source: nobelprize.org top photograph by Eliza Eddison bottom photograph by Allen Miller spring 2007 2 5 Important Scientific Breakthroughs of 2006 By Jeffrey Hartsough At Wake Forest University, Dr. Anthony Atala has grown a working Although it has not been approved by NASA yet, star- human bladder in his lab. By molding cells from a patient’s bladder shades could help shed new light (or shadow) on distant plan- onto a biodegradable scaffold and allowing the cells to mature over the ets. In the past ten years, astronomers have discovered more scaffold as it dissolves, Atala created a fully functional bladder. Over than 200 planets outside of our solar system. However, glare a four-year period, none of his seven test patients have had rejection from the stars these planets orbit prevent scientists from us- problems. The bladder is the simplest organ because it has no blood ves- ing telescopes to obtain important data about the planets sels. Soon, Atala will begin to engineer more complex organs like the such as their exact size and environments. A starshade is es- heart and kidney. This kind of technology could help eliminate waiting sentially a large parasol which positions itself between the lists for donors. telescope and the star, minimizing glare when photographing NIH the planet. After shielding glare for one planet, the starshade repositions itself to another target, operating in this fashion for two years before refueling. NASA Two pharmaceutical companies developed vaccines this year against two strains of human papillomavirus (HPV) which are responsible for The Hurriquake Nail was developed to simply create a better nail, something approximately 70 percent of cervical cancer cases. The vaccine will help to Fat Head Technology that is often taken for granted and given no second thought. What engineer Dr. decrease the number of invasive procedures associated with cancer treat- Improved Plastic Ed Sutt, a fastening engineer with Bostitch, realized is that in both hurricanes and ment, and is the first vaccine against any form of cancer. This discovery may Collation earthquakes, the nails that hold the wood together, and not the wood itself, are signal a change in the approach to cancer treatment and prevention in later the first to fail—either by being forced through the wood, pulled out of the wood, years through vaccination for viruses associated with the development of Shear Shank or shearing at a joint. Sutt made four changes to the traditional nail: the head of Technology cancer cells. the nail is increased by 25 percent, angled barbs are added to the shaft, the top of the shaft is twisted, and a high-carbon alloy has been used to best balance stiffness Deep Ring Technology Source for all text: Popular Science Magazine and pliability. While the nail increases sturdiness by an amazing 50 percent, using the nails only add $15 to the total cost of an average house—a miniscule invest- Harrison Laboratory Marsha Labunsky ment considering the lives and property it could save.
NASA developed aeropronic There is enough gold in the After 20 minutes of walking, 5 things crops, plants grown in air/ Earth’s crust to cover the this MIT-built robot adjusts that will mist environments with no entire land surface knee- its gait to suit its terrain. The soil and very little water, deep. One ounce of gold robot’s ability to adapt to is boggle your could1 possibly provide space flights can3 be stretched into a wire 80 another5 step toward more efficient with a supply of fresh oxygen and kilometers (50 miles) long. prosthetics and exploration with mind clean drinking water. Because robots. aeroponic crops grow in clean and By Gordon Wintrob, sterile environments, they ensure Allen Miller less contamination and faster food production. and Justin Chow The dark spots shown on this Pictures: NASA (1 and 2), ultraviolet image of the sun Jerzy Muller (3), Gordan Jovic have temperatures of thousands (4) and the National Science of degrees Celsius. The radiant Foundation (5). loops2 of gas flowing around the sun spots have temperatures of over one million A bolt of lightning is actually Text Sources: NASA, degrees. The reason for the sun’s high about the same size as a Astronomy Picture of the Day, Australian Mines Atlas, temperatures is thought to be attributed quarter or half-dollar. The Stormwise and MIT (from left to to the changing magnetic field loops that light emitted is so bright right). channel solar plasma. that4 the bolt appears much wider.
2 6 spring 2007 spring 2007 2 7 Harvard-Westlake Journal of Science 3700 Coldwater Canyon Avenue Los Angeles, CA 91604 www.hwscience.com/HWJS/index.html