The Amherst
ELEMENT Volume 5, Issue 2
Spring 2013
Letter from the Editors Thank you for picking up the Spring 2013 issue of the Element! We are sincerely grateful to all of our writers, editors, and layout staff for all their help this semester. We are excited to present articles on a variety of topics from a number of different scientific fields. This issue features articles about environmental science (Where Would We Bee Without Pollinators? by Anna Rasmussen ‘13), neuroscience (The Neuroscience of Buddhism: How Meditation Can Change the Brain by Emily Jackson ‘13), chemistry (Molecular Gastronomy: Where Science Meets Culinary Art by Xiao Xiao ‘16) and astronomy (Eye in the Sky by Lindsey Bechen ‘16 and Reimagining the Universe by Chanyoung Park ‘16) . This issue also features thesis research from senior honors students in neuroscience (Nguyen Ha ‘13, Narendra Joshi ‘13, and Haneui Bae ‘13) and geology (Danielle Santiago Ramos ‘13). Finally, we have a special letter from Alan Wang ‘12 describing his current post-graduate work at the NIH. Remember that we are always looking for new writers, editors, and layout staff for future issues, so if you’re interested, please join us next semester! Thanks for reading, and enjoy the issue! Sincerely,
Alice Li
Maile Hollinger
News-In-Brief Maile Hollinger ‘15 Genome of extinct frog revived Members of the Lazarus Project, an international team of scientists working towards de-extinction, have successfully created embryos from a frog that gives birth via its mouth. These aren’t just any embryos, however: the last of these gastric-brooding frogs died in 1979. Using a process known as somatic nuclear cell transfer, the research team injected nuclei from the extinct frog’s tissue into the eggs of the related Great Barred Frog. The resulting eggs grew and divided like embryos, though they died a few days later. Regardless of their lack of longevity, these embryos are an exciting first step towards more effective amphibian conservation. 3D printing replaces 75% of man’s skull After approval by the FDA, Oxford Performance Materials—a company that specializes in manufacturing for biomedical devices—has produced a 3D-printed implant to replace a patient’s skull. The implant was made of polyether-ketone-ketone (PEKK), a thermoplastic molecule that OPM uses in all of its parts. Though OPM has been sending 3D-printed, custom-made transplants overseas, its recent
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approval by the FDA allowed for surgical replacement of the patient’s skull with this printed transplant on March 4th. OPM hopes to use this technology in the US to create 3D-printed implants of other structures besides the skull. MeCam: the Orwellian police state realized? This January, Always Innovating Inc. developed the MeCam, a video-taking nano copter designed as a point-andshoot camera that can upload video to multiple social media platforms. The copter has four rotors and sensors that provide stable flight without causing the MeCam to bump into solid objects. Perhaps one of the most interesting aspects of MeCam is its “follow-me” feature, which enables it to follow the user around while shooting paparazzi-style video. This begs the question: is MeCam a technological innovation or a realization of Orwell’s 1984 police state?
Table of Contents
The Amherst Element Staff Senior Editor-in-Chief Alice Li
Junior Editor-in-Chief Maile Hollinger
Associate Copy Editors Anna Rasmussen Ji Hoon Lee Kevin Mei Xiao Xiao Haneui Bae Emily Jackson David Nam Lindsey Bechen Chanyoung Park Monty Montgomery
Feature Contributor Maile Hollinger
Layout
David Nam Kevin Mei Ji Hoon Lee Lindsey Bechen Chanyoung Park Emily Jackson
Get Involved! Send questions, comments, letters, or submissions to theAmherstElement@ gmail.com.
Cover Feature
1 Nuclear Fusion Reactor Eugene Lee ‘16 28 Night Sky Eugene Lee ‘16
Features
2 News-in-Brief Maile Hollinger ‘15
Letters
4 Alumnus Perspective Alan Wang ‘12 5 Where Would We Bee Without Pollinators? Anna Rasmussen ‘13 10 Molecular Gastronomy: Where Science Meets Culinary Art Xiao Xiao ‘16 15 Reimagining the Universe Chanyoung Park ‘16 20 The Neuroscience of Buddhism Emily Jackson ‘13 25 Eye in the Sky Lindsey Bechen ‘16
Thesis Research
8 Interview with Narendra Joshi ‘13 Kevin Mei ‘16 13 Interview with Nguyen Ha ‘13 David Nam ‘16 18 Interview with Danielle Santiago Ramos Ashley “Monty” Montgomery ‘16 23 My Experience of Writing a Neuroscience Thesis Haneui Bae ‘13
The opinions and ideas expressed in The Element are those of the individual writers and do not necessarily reflect the views of The Element or Amherst College. The editorials are a product of the opinions of the current editors-in-chief of The Element. The Element does not discriminate on the basis of gender, race, ethnicity, sexual orientation, scientific background, or age. Research findings published in The Element are not intended for wide distribution or for the reader’s profit. As a member of the Amherst community, please use the information and data presented in The Element judiciously.
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Alumnus Perspective Alan Wang ‘12 alan.wang@nih.gov After graduating from Amherst last year, I’ve been working as a fellow at the National Cancer Institute’s Division of Cancer Epidemiology and Genetics with Dr. Thomas O’Brien. I applied for this position by submitting an application through the National Institutes of Health’s website (https://www.training.nih.gov/programs/postbac_irta) and then contacting individual researchers to see if I could work with them. Epidemiology, often called the “science of public health,” can be roughly defined as the study of the distribution and determinants of disease and other health-related states in populations. Epidemiologists routinely collaborate with laboratory researchers, physicians, and statisticians in order to understand the distribution and biological basis of a disease. Many epidemiological studies have brought about important public health changes – the Framingham Heart Study, for example, established much of what we now know about heart disease and has helped shape many health initiatives. Dr. O’Brien has recently been studying the genetic determinants of how an individual responds to treatment for hepatitis C virus (HCV). Only a fraction of HCV-infected individuals who receive this treatment are able to clear the virus. Those that do not are at a much higher risk of developing liver cancer. Because the treatment is painful for the patient and quite expensive, much research has been focused on finding ways to predict whether a patient will respond to treatment. Other scientists have used genome-wide association studies (GWASs) to discover that two single nucleotide polymorphisms (SNPs) can help predict whether an individual with HCV will respond to treatment. In a typical GWAS, scientists select several hundred thousand SNPs to genotype in a group of people with some health-related trait (cases) and a group of people who are free of the trait (controls). If one allele of the SNP is much more frequently found in controls, for example, the SNP is considered to be associated with the trait (if 5% of cases have an A at a SNP while 90% of controls do so, then this SNP is likely associated with some gene that interferes with the trait). The two SNPs that the scientists discovered do not explain the differential HCV treatment responses but mark some gene that does. Dr. O’Brien and his collaborators recently discovered a novel interferon gene that might address this issue. The novel gene contains a genetic variant that is highly associated with the two previously discovered SNPs and determines whether or not a full-length protein is produced. Individuals that produce this protein have a significantly reduced chance of responding to treatment and clearing the virus. In addition, this newly discovered variant is better than the two previously discovered SNPs at predicting how a patient will respond to HCV treatment. Although much more work is needed to characterize this protein, Dr. O’Brien’s discovery will hopefully help clinicians determine how to treat patients with HCV. I am currently helping Dr. O’Brien conduct some follow-up studies to further explore this newly discovered gene. Most of my time is spent organizing and analyzing the data coming in from our collaborators. I have also helped Dr. O’Brien draft several proposals and prepare a few manuscripts for publication. In addition, there have been numerous events planned for all the fellows here to hang out and talk. Feel free to contact me if you have any questions about epidemiology or working at the NIH!
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Letters
Where would we Bee without Pollinators? Anna Rasmussen ‘13
Pollinators are awesome. Organisms such as birds, bats, are used commercially for their “ecosystem services.” Pollinating lizards, bees, beetles, flies, and butterflies can act as pollinators, insects are responsible for 84% of crop pollinations in Europe,4 often receiving a nectar reward for delivering pollen from flower to and wild bees and honeybees make up an important part of that flower. The coevolution between pollinator and plant is an iconic group. Around 75% of global crops depend on pollinators,5 and image of mutualism and the “evolutionary arms race” between many conservation websites such as http://www.pollinator.org species (and those who watched the film Sexual Encounters of the and http://thehoneybeeconservancy.org kindly remind us that Floral Kind in Biology 181 should understand how exciting this without pollinators we would not have many of our favorite fruits, is). Pollinators can be generalists and visit a wide variety of flower vegetables, nuts, oils, fibers and other raw materials. species, or specialists that will lead to to mutual dependence of Awareness about bees has become more mainstream in pollinator and flower. recent years because With the changing of the mysterious climate, loss of natural disappearance of habitat, pesticide use, honeybee hives. Many and loss of biodiversity, people may have heard many plant and about the disappearing pollinator species are honeybees in the at risk. The loss of US and may even be pollinators is not a familiar with Colony trivial phenomenon. Collapse Disorder Humans as well as other (CCD), a term used organisms (including to describe the livestock) depend on abandonment of pollinators for fruits beehives by the entire and seeds to eat, colony. Since 2006, many plants depend between 30-90% of on pollinators to honeybee colonies enhance reproduction, have collapsed. One and pollinators help study found that the maintain biodiversity. pesticide imidacloprid Both wild pollinators causes colony collapse and domesticated and massive bee death Figure 1: A honeybee covered in pollen visits a flower. honeybees are in a manner typical of important for natural CCD. Surprisingly, bees ecosystems and the agricultural industry, thus their decline is the were affected at levels even lower than what a typical bee would be subject of burgeoning research and conservation efforts. exposed to when visiting crops treated with pesticides or foraging in surrounding environments.6 A different study looked at the Bees and Crops effects of pesticides on another important bee, the bumblebee, and Bees are social insects with complex behaviors that intrigue found similar results. Researchers found that bumblebees exposed scientists. From the iconic “waggle” dance used to convey to imidacloprid and λ-cyhalothrin, both found in many common information about flower location to their startlingly good pesticides, displayed impaired natural foraging behavior and memory for optimal1 and caffeine-producing flower locations,2 increased worker mortality.7 While other studies linking pesticides bees have proven to be more than meets the eye. Researchers to colony collapse have been debated, and there is a need for further have looked at the memory of bees to understand their behavior investigation to solidify exactly how pesticides play a role in CCD,8 and navigation and even to shed light on how sleep deprivation it is clear that common pesticides affect bees on the individual affects humans.3 Bees also play a vital role in pollinating crops and level, and these individual effects can disrupt the entire colony.7 The Amherst Element, Vol 5, Issue 2. Spring 2013
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“Pollinators are obviously important for agriculture, but they are also tremendously important for natural systems. Many systems are stressed by a loss of pollinators, in particular biodiversity hot spots since specialized plant-pollinator interactions are common in these areas.� CCD has been an area of concern for the agricultural industry. Without honeybees, farmers see a reduction in crop productivity. Understanding the role of pesticides may help prevent CCD in the future, but the disappearance of honeybees is not the only problem facing us today; other bees and pollinators are on the decline as well, posing a large threat to crops and ecosystems.
production and the threat these actions pose to a diverse set of pollinator species. Researchers suggest investigating pollinator ecology so that humans may restore habitats that have been destroyed. Pollinators are obviously important for agriculture, but they are also tremendously important for natural systems. Many systems are stressed by a loss of pollinators, in particular biodiversity hot spots since specialized plant-pollinator interactions are common in these areas.5 Pollinators help sustain reproductive potential and genetic diversity in many ecosystems, yet there has been little focus on restoration of pollinator populations.5 As pollinator populations decline, we need to understand why they are disappearing and how to restore their populations. Pollinators obviously play an important role for human and biodiversity health, and restoration and conservation are necessary. Projects such as Status and Trends of European Pollinators (STEP) have dedicated themselves to understanding why pollinator insects are disappearing and making a Red list of threatened bee species,4 so there might still be hope for pollinators yet.
Pollinator Diversity Honeybees alone will not increase crop yields, as one recent large-scale study shows. This study used data from 600 fields on 6 continents to compare the effectiveness of wild pollinators and honey bees at increasing the fruit yield of 41 different crops.9 The findings show that visits from wild pollinators increased fruit set in 100% of crops tested, while visits from honeybees only improved fruit set in 14% of crops.9 Visits from wild pollinators also increased fruit set twice as much as visits from honeybees.9 Garibaldi et al. (2013) argue that while honeybees are easy to manage and move to farms, they are not a substitute for wild pollinators, and agricultural practices should focus on increasing honeybee numbers in addition to maintaining nearby habitats for wild pollinators. Other recent studies on almond crops in California support and explain in more detail how the presence of wild pollinators increased pollination of crops. The studies found that wild pollinators influenced pollination in two ways: first by changing the behavior and flower preference of honeybees in addition to pollinating plants themselves,10 and second by pollinating during high wind or adverse weather when honeybees did not pollinate plants at all.11 All of these studies show that diversity of pollinator insects, not just honeybees, are important for increasing crop production. Thus, maintaining wild pollinator and honeybee populations is important for sustaining agriculture. To do so we must resolve the paradox between increasing agriculture land and the use Figure 2: A seven-spot lady bug pollinates a spurge flower. of pesticides to enhance crop
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Figure 3: Examples of fruits and vegetables that depend on pollinators. References 1. Lihoreau, M., Chittka, L., Le Comber, S. C., & Raine, N. E. (2011). Bees do not use nearest-neighbour rules for optimization of multi-location routes. Biology Letters, 8(1), 13–16. doi:10.1098/ rsbl.2011.0661 2. Wright, G. A., Baker, D. D., Palmer, M. J., Stabler, D., Mustard, J. A., Power, E. F., … Stevenson, P. C. (2013). Caffeine in Floral Nectar Enhances a Pollinator’s Memory of Reward. Science, 339(6124), 1202–1204. doi:10.1126/science.1228806 3. Beyaert, L., Greggers, U., & Menzel, R. (2012). Honeybees consolidate navigation memory during sleep. Journal of Experimental Biology, 215(22), 3981–3988. doi:10.1242/ jeb.075499 4. Wild bees: Champions for food security and protecting our biodiversity. (n.d.). ScienceDaily. Retrieved March 8, 2013, from http://www.sciencedaily.com/releases/2012/09/120906074251. htm 5. Dixon, K. W. (2009). Pollination and Restoration. Science, 325(5940), 571–573. doi:10.1126/science.1176295 6. Use of common pesticide, imidacloprid, linked to bee colony collapse. (n.d.). ScienceDaily. Retrieved March 8, 2013, from http://www.sciencedaily.com/releases/2012/04/120405224653. htm 7. Gill, R. J., Ramos-Rodriguez, O., & Raine, N. E. (2012). Combined pesticide exposure severely affects individual- and colonylevel traits in bees. Nature, 491(7422), 105–108. doi:10.1038/ nature11585 8. Henry, M., Beguin, M., Requier, F., Rollin, O., Odoux, J.-F., Aupinel, P., … Decourtye, A. (2012). Response to Comment on “A Common Pesticide Decreases Foraging Success and Survival in Honey Bees”. Science, 337(6101), 1453–1453. doi:10.1126/ science.1224930
9. Garibaldi, L. A., Steffan-Dewenter, I., Winfree, R., Aizen, M. A., Bommarco, R., Cunningham, S. A., … Klein, A. M. (2013). Wild Pollinators Enhance Fruit Set of Crops Regardless of Honey Bee Abundance. Science. doi:10.1126/science.1230200 10. Brittain, C., Kremen, C., Klein, A.-M.. (2013). Brittain, C., Williams, N., Kremen, C., Klein, A.-M.. (2013). Biodiversity buffers pollination from changes in environmental conditions. Global Change Biology, 19 (2): 540 DOI: 10.1111/gcb.12043 11. Brittain, C., Williams, N., Kremen, C., Klein, A.-M.. (2013). Synergistic effects of non-Apis bees and honey bees for pollination services. Proceedings of the Royal Society B: Biological Sciences, 280(1754): 20122767 DOI: 10.1098/rspb.2012.2767 Figure 1: [Photograph]. Retrieved March 25, 2013, from: http:// ordinarypen.files.wordpress.com/2012/07/bee-collectingpollen2.jpeg Figure 2: Africa Gomez (Photographer). (2012) [Photograph]. Retrieved March 25, 2013, from: http://abugblog.blogspot. com/2012/03/unexpected-pollinators.html Figure 3: [Photograph]. Retrieved March 25, 2013, from: http:// www.drtindall.org/Fruits%20and%20Vegetables.jpg
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Thesis Research
Interview with Narendra Joshi Kevin Mei ‘16 Major: Neuroscience Thesis Advisor: Luke Remage-Healey, Professor of Psychology at the University of Massachusetts Amherst Introduction On weekends, Narendra Joshi can be found at UMass, observing zebra finches in enclosed sound chambers and studying their neural responses to sound tones. Narendra has worked in the Healey lab at the Center for Neuroendocrine Studies for two years. He started off as an assistant in his sophomore year, learning the techniques, getting to know the people, reading the literature, and performing different experiments on zebra finches. Last summer, Narendra stayed on campus to start his thesis project and in July, after discussing ideas with Professor Healey, Narendra came up with his own topic. The Healey Lab studies the role of steroid hormones on the auditory system of zebra finches. In particular, Narendra uses electrophysiological techniques to study the caudomedial nidopallium (NCM) region of the zebra finch’s brain. The NCM region is a secondary auditory area and part of the auditory pathway: when sound enters the ears, it first passes though the cochlea, which is mainly responsible for converting the mechanical stimuli into neural impulses, before it reaches the brain stem and cortex. The NCM is the first region in the cortex to process, or make sense of, the sound. Narendra studies the role of a steroid hormone called estradiol, a type of estrogen hormone, in NCM. Thesis Idea Narendra’s project is to study the role of estradiol in modulating the ability the of NCM to discriminate between sounds. To this end, Narendra plays sound tones of different frequencies (in Hertz) in an enclosed sound chamber and observes the neural responses of the zebra finch (Fig. 1). The first part of Narendra’s thesis project was to determine the baseline for how sensitive the zebra finch is to frequencies of sound. That is, what is the smallest difference in frequency to elicit a response? The range of frequencies that is most relevant to zebra finches is between 200 Hz and 1000 Hz. The higher the frequency, the larger the difference must be before the zebra finch can recognize a change. This is the same for humans as well. By a spectrum known as the mel scale, humans are similarly not good at detecting differences at large frequencies for the same reason— lower frequencies are more relevant to our lives. Thus, at high frequencies, say 3000 Hz, a 50 Hz increment will sound like the same tone and won’t elicit a response. Narendra found that at the range of frequencies relevant to zebra finches, a change in 20 Hz is enough for the zebra finch to differentiate between the tones. Narendra determined this by observing electrophysiological recordings of neural activity in the brain of the zebra finch. When Narendra first plays a sound tone,
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the neural response is strong and the graph of the brain’s activity shows a peak. However, as the zebra finch becomes accustumed to the sound, the graph will eventually flatten. This is known as habituation and applies to humans as well—when a stimuli has been repeated and an animal becomes used to it, the response weakens. After the zebra finch has become habituated to a tone, Narendra will play a tone at a different frequency—perhaps a 10 Hz increment. If there is a response, the graph will peak once more, but if there isn’t, the graph will remain flat. Narendra found that an exposure to an increment of 20 Hz is enough for the graph to become active again as the zebra finch’s brain works to process the new tone.
Figure 1: An electrophysiological recording of neural activity in the NCM region of the zebra finch in response to sound tones. We see that when sound a is initially played, there is a strong response but it weakens eventually due to habituation. When sound b is played, there is again a neural response. Now that a baseline sensitivity has been established—the zebra finch is sensitive to changes in quantities of 20 Hz— Narendra wants to see how estradiol will affect this sensitivity. Will an infusion of estradiol into the NCM region of the brain make the zebra finch more or less sensitive to changes in frequency? Narendra’s initial hypothesis was that estradiol would increase the zebra finch’s ability to detect differences. Previous studies have shown that estradiol strengthens the NCM response to relevant sounds. This may be in response to mating calls or their own songs. Techniques In general, Narendra sets up his experiments by first selecting a zebra finch from the aviary. The bird is anesthetized before he
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Thesis Research performs surgery on the head to expose the bone. The procedure is relatively safe and non-invasive. A metal head-post is attached to the zebra finch’s skull and this head-post is attached to the stereotax (Fig. 2). The stereotax is an apparatus that is used to both keep the bird still and to very precisely manipulate needles and electrodes.
Figure 2: The stereotax apparatus for electrophysiological experiments on zebra finches. The skull is first surgically exposed before electrodes and needles can be inserted. (Tremere, Terleph and Jeong) Electrodes must be put into the NCM region in order to detect neural activity. The location of the NCM is well known from many previous experiments. In mice and humans, there are junction points on the skull that are fairly universal and can be used to determine the locations of regions of the brain. In the zebra finch, Narendra uses blood vessels as reference points to determine the location of the NCM. Using the stereotax to carefully move and position the electrodes, Narendra puts the electrodes into the NCM region. The bird is placed in an enclosed chamber where sound tones can be played without background noise. Neural activity can then be observed on a computer. The bird is awake while sounds are played. To manipulate the estradiol concentration in the NCM region, Narendra uses a technique known as retrodialysis. Retrodialysis is a method for drug delivery that allows estradiol to be injected and diffuse into the brain. It utilizes a semi-permeable probe that only allows certain molecules to diffuse in and out.
because in research, it’s inevitable you’ll encounter problems. You are, after all, doing things that other people haven’t done before. For Narendra, it was finding the site on the NCM region in the brain where he had to insert the electrodes and finding the smallest change in frequency that would cause a response (20 Hz) that have made his efforts worth it. Towards the beginning of his project, it was hard for him to pinpoint a particular position on the NCM that exhibited the adaptation behavior. Seeing the strong intial signal that eventually weakened due to habituation was very exciting. Presently, having analyzed his experimental data, Narendr has found out that estradiol causes the bird’s sensitivity to differences in frequencies to be weakened. That is, when estradiol is infused, the NCM of zebra finch shows a smaller response to the same amount of change in frequency of tones. This is counter to what Narendra hypothesized about the effects of estradiol on the NCM and it opens up many possibilities about what might be happening. Habituation and adaptation are forms of learning. If memory were not involved, then an organism wouldn’t learn to get used to a stimulus such as a sound. Because NCM is involved in memory, an implication of Narendra’s work might be how estradiol affects the formation of memory in zebra finches. Narendra has always been interested in neuroscience and after working in the Healey lab, where he was given a lot of independence for his research, he wants to continue in the field of neuroscience. Narendra hopes to continue to look at how parts of the brain process information from sensory stimuli and to study further sensory perception and processing. To that end, after graudation, Narendra will be working as a research assistant in a lab that studies the olfactory system (smell) and he looks forward to graduate school. References 1. Thanks to Narendra Joshi, for a great interview and for explaining everything so clearly! 2. Tremere, Lisa A, et al. “Bilateral multielectrode neurophysiological recordings coupled to local pharmacology in awake songbirds.” Nature Protocols (2010): 191-200.
Results, Implications, and Future Directions The challenges Narendra faced were mainly picking a thesis topic and then designing experiments. At the start, he had many faulty experimental recordings and surgeries. He’s learned from experience over the course of his experiments to have patience and that is the advice he’d give researchers: be patient and keep trying The Amherst Element, Vol 1, Issue 2. February 25th, 2008
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Molecular Gastronomy
where science meets culinary art Xiao Xiao ‘16
Introduction What do ancient Egyptians and a typical modern Frenchman have in common? They both love foie gras, the plump and delicious liver of a fattened duck or goose. Of course there is no evidence that foie gras was the name of that dish back in the 2000 BC, but ancient hieroglyphs and Egyptian wall paintings have demonstrated the existence of foie gras production. In essence, the Egyptians were the first to adopt unconventional technologies into their own culinary adventures. Gastronomy is the art behind food consumption. Gastronomists place almost equal emphasis on both the food and the culture behind it. Molecular gastronomy results when science decides to marry art. It is impossible to do the art any justice in a single article so it is sufficient to consider that to a molecular gastronomist, food is simply a medium for the chef to communicate with the diner. The chef uses his dish to get his message across. The science aspect is a lot more exciting as it involves a multitude of scientific knowledge just to create a single dish: physics and chemistry, especially thermodynamics and energy transfer, come in mostly in the equipment design while biology plays a crucial role in food safety and ingredient quality control. Hence, the line between a food scientist and a molecular gastronomist is often blurred. A Little History Molecular gastronomy itself is very broadly defined. Up to today, the culinary realm has yet to agree on some concrete
Fig. 1: Ancient Egyption carving depicting force-feeding of geese
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boundaries on what constitutes molecular gastronomy. What is universally agreed upon, however, is that one of the pioneers of molecular gastronomy is Ferran Adrià (born in 1962) who founded the Spanish restaurant El Bulli. Interestingly, he himself despises the term “molecular” as the name adds an arcane spin to otherwise simple dishes. Others soon followed with various forms of media ranging from dishes, books, lectures and even to videos. Prominent names such as Nathan Myrvold, Hervé This and Heston Blumenthal have emerged at the forefront of this culinary revolution. Ultimately, most chefs have begun to embrace and incorporate this new concept into their kitchens around the world because of the benefits from the scientific techniques involved. The Science: Water Although molecular gastronomy employs a variety of fancy techniques such as blast chilling (rapid lowering of food temperature to below 68oF to restrict bacterial growth), the root of the innovation lies in some basic scientific principles. For instance, the property of water plays a crucial role. It is not uncommon to find raw ingredients that have close to 90% water content by mass. In essence, when we chew on cucumber slices and celery sticks from the Val salad bar, we are munching on a cage of vegetable fibers filled largely with nutritious juices. Although meat generally contains much less water than vegetables or tofu, the effect of water cannot be ignored as well. In terms of physiology, meat is just a piece of animal muscle tissue. Hence, within the meat itself there are microscopic muscle cells, each containing cellular fluid that is largely water. However, this water proves to be detrimental when the meat is stored in a conventional freezer. Due to the hydrogen bonding network in water (polar inter-molecular bonds between H2O molecules that confer water its dazzling properties), it expands when it freezes. Thus, the muscle cells will have their cell membranes ruptured due to the increase in volume of their individual contents. In a home freezer, the typical temperature is roughly -3oC. Hence, the freezing of a chunk of meat happens only gradually in a layer-by-layer process until the chill reaches the center of the meat. Essentially, if the piece of meat is large, the center may never get frozen completely. Couple this phenomenon with the water expansion and we have a serious problem. As the outer layer gets frozen, the cells there expand and push the cells in the inner layer. The inner cells have to accommodate the increased volume and they do that by moving away some of its content, such as the cellular fluid, which is made of water. Thus, the longer the meat stays in the freezer, the more
Letters
Fig. 2: Formation of microscopic ice crystals damages muscle structure aggregated the water gets. Eventually, the water will form ice crystals near the center of the meat, messing up the tissue composition and arrangement. After thawing the meat for dish preparation, we will end up with a piece of meat that tastes flaky at best (such as red meat like steak) or crumbles into pieces at worst (fish fillets). How molecular gastronomists deal with this issue is to use blast freezers for larger chunks of materials and liquid nitrogen for smaller samples. A blast freezer is a souped-up freezer capable of flash freezing. That is to say, the material in a blast freezer will have its temperature reduced rapidly to a state well below the water freezing point so that the microscopic water movement is kept at a minimum to prevent structural tissue damage. The outcome is the preservation of the texture for the ingredient. Similarly, liquid nitrogen produces the same effect of temperature reduction within a short amount of time. Of course, it is impractical to purchase and maintain a blast freezer or liquid nitrogen tank in our dorms or even at home. Even so, there is a moderately easy alternative in the form of brine chilling. Brine chilling relies on the lowered freezing point of salt water and typical brine consists of ice, a little water and salt that weighs a total of 20% of the ice mass. The amount of ice should be roughly equivalent to 1.5 times the mass of the materials to be frozen. Finally, to prevent the taste of brine getting in the way, it is recommended to vacuum seal the material. A perfectly managed brine should theoretically reach -40oC, much more powerful than a home freezer. The Science: Thermodynamics Water comes in more prominently in the cooking process. For example, if we decide to prepare the same piece of steak we have just thawed, water interferes again. Due to the water content, different layers of the steak are cooked with different methods, even though it is on the same cast iron skillet. The layer of meat touching the skillet gets the energy from the pan via conduction. Hence, the speed of the cooking is the highest and that is how a delicious, crispy layer of crust forms. The intense heat induces a considerable Maillard reaction, a reaction between amino acid and sugars on the steak surface. This reaction is also responsible for the mouth-watering aroma of grilled meat and the characteristic brown color. The other layers, however, are cooked differently. Directly
above the Maillard reaction layer there is a layer of insulation. The name is a misnomer that there is still heat flow from conduction. However, due to the water content, the rate of cooking is much slower since water has a high specific heat capacity. That means that it takes much more thermal energy and hence, much longer, to raise the temperature of water by a single degree. That prevents this layer, as well as the portion above, from effectively cooking. The Maillard layer will have its water content quickly depleted due to the rapid heating. The layer above, though slower, will have its water content removed eventually as well. All the water now becomes a water vapor that forms a mini-convection system that steams the top most layer of the steak. Hence, it is nearly impossible to achieve the same kind of consistency in texture for the entire chunk of steak. Molecular gastronomists get around the problem by employing the sous vide process. Sous vide uses a water bath with a precise temperature control. The ingredients are sealed in a vacuum bag and placed inside the bath until it is done. Cooking in its barest form is the transfer of enough energy to trigger a series of chemical reactions in the ingredient and kill off any harmful pathogens. A water bath achieves the energy transfer aspect while temperature and time control achieve the food safety aspect. The benefits of having a water bath are the uniformity and relative time-independence. Sous vide relies on the chemical principle of thermodynamic equilibrium which is essentially a set of laws governing the flow of thermal energies in the form of heat. In the kitchen, it means that given enough time the inner most portion of the ingredient, such as a steak, will reach the same temperature as the water. Meanwhile the outer portion of the steak will never get overcooked in the context of a kitchen because of the equilibrium condition. In essence, the steak will never exceed the water temperature despite sitting in the bath for prolonged time unless the chef leaves the steak there for hours. However, the downside of sous vide is exactly the uniformity as well. For example, it is impossible to find the delicious crust of the
Fig. 3: Temperature-controlled water bath with vacuum-sealed ingredients The Amherst Element, Vol 5, Issue 2. Spring 2013
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Letters steak as the consistency between the outer and inner portions is uniform. Hence, chefs have implemented touch-up techniques such as a quick sear or even blow torch to produce the perfect steak, juicy and tender in the inside while aromatic and crisp on the outside.
4. Calculating The Speed Of Light With Kraft Singles And Your Microwave. 2011. Seattle Food Geek, Seattle. Web. 30 Mar 2013. <http://seattlefoodgeek.com/2011/01/ modernist-cuisine-geeky-food-trick-calculating-the- speed-of-light-with-kraft-singles-and-your- microwave/>.
Molecular Gastronomy And You Even though Amherst has a humongous annual endowment, we are still lacking in terms of student-friendly kitchens. However, molecular gastronomy does not necessarily involve fancy gears and sophisticated machineries. A lot of interesting phenomena can be done using a simple microwave. It is possible to create an authentic Asian steamed fish fillet with a humble microwave. All you need is fish, some microwave-resistant foil, soy sauces and rice wine with a little ginger and coriander for garnish. Microwaving at medium power for 5 minutes will do the trick. For those that are little more adventurous, try this: 1. Look for a cardboard and cut a large circular patch like a pizza dish 2. Obtain some cheese slices and completely cover the round cardboard 3. Disable the spinning function of microwave 4. Microwave the cheese-covered cardboard for 2 minutes at full power 5. Measure, in meters, the distance between the center of the two largest patches of bubbling, melted cheese 6. Multiply that by two and then multiply that by the frequency, in hertz, of the microwave 7. Repeat this for consistency and you will realize the final product of multiplication is very close to a well-known constant In case you are interested in knowing more about molecular gastronomy, simply search the library catalogue for names such as Hervé This or Nathan Myrvold. Both authors have written some fantastic books with stunning pictures for illustration. One Fig. 4: A demonstration of microwaved cheese plate particular recommendation is the book series Modernist Cuisine by Nathan Myhrvold in the Keefe Science library. On another note, Professor O’Hara is in the process of organizing a science course meant for non-majors titled Molecular Gastronomy. Hence, look out for this course in the next pre-registration period for the academic year 2013-2014. Acknowledgements 1. A BRIEF HISTORY OF FOOD. 2012. Hubpages, New York State. Web. 30 Mar 2013. <http://chefmac. hubpages.com/hub/foodhistory 2. The Culinary Institute of America, . Cooling, Reheating, & Thawing Foods Safely. 2006. Chef ’s BladeWeb. 30 Mar 2013. <http://chefsblade.monster.com/training/ articles/225-cooling-reheating-thawing-foods-safely>. 3. Myhrvold, Nathan. IN HOT WATER. 2011. Scientific American Web. 30 Mar 2013. <http://www.scientificamerican.com/article. cfm?id=the-science-of-sous-vide>.
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Thesis Research
Interview with Nguyen Ha ‘13 David Nam ‘16 Major: Neuroscience
David Nam: Who are you working with for your thesis? Nguyen Ha: Professor Williamson of the Biology Department. D: Since when have you been working with him? How has it been having him as your thesis advisor? N: I’ve known Professor Williamson for quite some time and I know he’s a nice guy and a good mentor. I’ve worked in his lab since HHMI [Howard Hughes Medical Institute research fellowship] in the summer after my freshman year and since then, he’s been my academic advisor, my laboratory PI [primary investigator], and now my thesis advisor. My impression of him hasn’t changed and he knows a lot about science and things outside of science. He’s a great, supportive mentor. He is one of the main reasons I chose to work with his lab. D: Can you tell me about your thesis? N: The Williamson lab works on phospholipid transporters, which compose a family of membrane proteins that transport specific phospholipids across membrane. Differences in phospholipid composition between two membrane leaflets are important in various cellular phenomena such as apoptosis [programmed cell death] and cell recognition. We don’t know how they work together, but we do know that transporters form complexes with subunits during the transportation of phospholipids. In prior works, Professor Williamson determined which conformation during the reaction cycle of the transporter is most susceptible to binding with the subunits. My question is to determine if the subunits physically dissociate from the transporter during the cycle. Now, there are two scenarios: 1) after the subunit binds with the transporter, they stay together though the binding affinity fluctuates during the reaction cycle, or 2) the subunit dissociates to have another subunit replace it. That question may be important in understanding the underlying mechanism of how these proteins work. D: How do you go about doing that? N: I tag both transporter and subunit genomically with fluorescent proteins called Dendra2. But it is more complicated than I just made it seem. The unique characteristic of dendra-2 is its ability to undergo photo conversation when you shine a laser on it. Hence, every time a new transporter protein is made, it will be attached to a fluorescent dendra-2. Initially, all Dendra2 are green in the yeast, but every time you shine a laser on it, all the proteins turn red.
D: Oh? That’s interesting. N: So imagine in a yeast cell a population of lots of red Dendra2 tagged to the proteins. As new proteins are made from the genome, we have new transporters and subunits that have green Dendra2 attached. If the transporters and subunits do not dissociate, you would expect pairings of red-red and green-green protein complexes, until the new green-green guys completely displace the red-red guys. But if there is exchange between transporters and proteins, they split, mingle, and recomplex, and chances are you will have lots of red-green Dendra2 pairs. D: This is so cool! But how is this relevant? N: Well, the nifty thing is that only pairs of same-colored Dendra2 depolarize light. By detecting that depolarization, I can know if the configuration of the complex is mainly red-red, green-green, or red-green. If it is red-green, there won’t be any depolarization, but if it is mainly red-red and green-green, there will be depolarization. We then simply measure depolarization. D: Well, I think that sounds pretty cool. Now that I have a basic idea of your research, what applications does it have in the general context of biology? N: Hmm…that’s an interesting question. We have no idea about its potential application at the moment, but the assay might be useful in other contexts of biology. D: So I’m guessing you can kind of pass this project down to others? N: It would be nice if this works because it means we would have an improved, different assay to quantitatively detect whether proteins physically dissociate from each other during the reaction cycle. It would be a nice addition to the split-ubiquitin assay, which tests for association between proteins. D: You obviously love your project. What do you like most about all of this? N: I like conducting research because it’s fun and I love the opportunity to learn. When things start working and you see in one electrophoresis gel all your controls and all the patterns you expect out of the DNA digestion, it’s a truly rewarding moment.
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Thesis Research The way I’m interacting with and getting through my thesis reflects on the way I’m getting through real life problems; whenever I’m frustrated, I try to do different variations of the same thing again and again, expecting different results. It’s how I approach life. It didn’t work well so far. D: I see. You want to give examples of challenges and difficulties you faced along the way? N: Well. When I came into lab, I had this tendency to do small different variations of the same thing over and over again, expecting to get a different result. It took me months to get my first clone. Essentially, I was the definition of insanity. When experiments did not go as planned, I thought if I repeated things and more closely approximated the “recipe” or whatever formula or protocols I was given, I would get things working. I also was a big “one-man team” person: when experiments didn’t work, I sort of just pushed it under and didn’t really talk to my fellow lab mates about it. I was just doing, but I wasn’t really going anywhere for the longest time. All of that had to change. And eventually I managed. It’s been a great learning experience. D: What are some tips you might give to future students conducting a thesis? N: Talk to your principal investigator a lot; talk to your PI about the details, procedures, and potential sources of failure. Secondly, never just do things without knowing concretely where you’re going, where you’re coming from, what you know, what you’re trying to find out, how you’re going to find it out, and what you will expect. And also, start writing real early, and take wonderful notes: at the end of your thesis, those are the only things that stay for anybody who might care about your project. D: What are your future plans? N: I was accepted to and will be attending Rush Medical School in Chicago. D: Congratulations!
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Letters
Reimagining the Universe Chanyoung park ‘16
curvature: Jeff, an Amherst student, stretches and suspends a What is a Black Hole? Everyone’s heard of black holes. But what exactly are they, rubber sheet so that the surface is completely taut. If he places a weight on it, the sheet will depress in that location. Now say Jeff and where do they come from? The term “black hole” was first coined by John Wheeler in replaces the original weight with a heavier one. What will happen? 1964. But even earlier, others had predicted and even described The sheet will sag even more. But imagine that he somehow finds characteristics of these phenomena.1 About a century after Sir a new weight, one that is impossibly heavy, and places it on the Isaac Newton characterized gravity, John Michell, a Cambridge sheet. Our brain tells us that the sheet will rip where he placed the geologist, suggested that there may exist objects in the universe weight. For our sake, however, this rubber is incredibly strong and whose gravitational pull was so strong that the escape velocity - the impossibly elastic. When he places the impossibly heavy weight on speed that an object needs to be travelling at in order to escape the sheet, it will now create a bottomless hole. That is what our modern understanding it - was greater than of a black hole is: a the speed of light.2 bottomless hole in the Around the same time, curvature of spacetime Simon Pierre LaPlace so deep that nothing can also put forth the escape.5 idea that the largest and brightest objects How are black might be invisible.1 holes formed? Then came Now that we have a Einstein, with his new brief idea of the history Theory of General of the black hole, we Relativity. Within it, can start to consider he stated that the how they might be current understanding formed. To understand of the universe black hole formation, was imperfect. He we need to differentiate proposed a theory in between two different which spacetime itself types of black holes: could be imagined as the smaller ones formed being flat, like a sheet; by star collapse and a gravitational body supermassive black would push down on this sheet and Figure 1: An artist’s representation of what a black hole would look like in space. holes that form the center of some galaxies. create a curve within Smaller black holes (and I use the term “smaller” very liberally, spacetime. In that sense, he predicted the curvature of spacetime, an important concept to the modern understanding of black holes.3 as these can easily range from a diameter of a few kilometers Ironically, he and Sir Arthur Eddington were stout opponents of to thousands of kilometers.) are thought to form through star the black hole theory, as scientists at the time believed the strongest collapse. Once a star uses up its fuel in the fusion reactions at its core (mainly by converting hydrogen into helium), it will begin to gravitational forces in the universe were due to stars.1, 4 But probably the most famous contributor to our modern form heavier elements through fusion as well. In other words, the understanding of black holes is Stephen Hawking. Using Einstein’s star, once it runs out of its primary fuel source, will start to use the idea of spacetime curvature, he sought to define exactly how a byproducts as fuel and create even heavier byproducts. However, black hole functioned. A black hole is an object of incredible this process is not permanent. Once the reaction reaches the stage density whose gravitational pull is so strong that it pulls other of producing iron, the star can usually no longer continue its objects towards it. But let’s imagine it in the sense of spacetime reactions; it is at this point that the star begins to approach the end The Amherst Element, Vol 5, Issue 2. Spring 2013
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Letters
Figure 2: How a black hole affects spacetime of its life. There are then two possible fates: if the star is sufficiently massive, it may compress and form a black hole; otherwise, it may shed mass and then collapse to form a white dwarf or neutron star. If the star collapses with more than 1.4 solar masses, the star will form a neutron star. One solar mass is approximately 2x1030 kg, or the currently accepted mass of our Sun.6 But, if it has enough mass (a figure known as the Chandrasekhar Limit), a black hole forms. Usually, if the star exceeds 2 solar masses, gravity will compress the star and create a black hole.7 There also may exist supermassive black holes at the center of some galaxies, even our own (one estimated to be 4 million times the mass of our Sun)!6 Only recently have scientists determined direct evidence for their existence through the observation of active galaxies such as M87 or NGC4261. These galaxies show a huge concentration of solar masses, on the order of three billion, in a size similar to that of our Solar System. Further analysis has also shown that there is a rapid rotation of matter.8 So how did these structures form? One theory is that the origins of these black holes are similar to the collapsed star formation theory stated above. Another theory is that many smaller black holes combined and merged into one supermassive black hole. Alternatively, some also suggest that giant gas clouds, once they reach enough mass, collapse together and form these supermassive black holes.9 However, much is still unknown about them and this topic is still an active field of research. Components of Black Holes A black hole can be divided into two key parts: the accretion disk and the event horizon.10 For simplicity’s sake, let us imagine that we are approaching the black hole from the outside. The first structure we would encounter is the accretion disk. This is the spiral of matter that has become trapped in the gravitational field of the hole and is slowly being sucked in. In this area, matter is constantly in motion and constantly bumping into and rubbing against each other. Therefore, great amounts of friction build up and enough heat accumulates that the accretion disk begins to emit X-rays. In this process, mass can also be
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converted into energy, similar to the way a nuclear bomb functions. But in a nuclear bomb, only 0.5% of the mass is converted to energy – compare that to the 10% that is converted in the accretion disk.11 The event horizon is the point that separates the inside of a black hole from the outside. The “outside” of a black hole is the accretion disk and what we can see of a black hole. The “inside” of the black hole is where the gravitational force is so strong that no information can escape. Therefore, we cannot directly observe the event horizon.11 Say an object is approaching the event horizon. What would we see? In fact, we cannot see the object entering the event horizon; all we would see is the object getting closer, and closer, and closer but in fact never quite reaching it because the light from the object also gets increasingly redshifted– its frequency of light shifts toward longer frequencies due to its movement away from us.12 Therefore, we do not see the objects “hit” anything. The observation of event horizons is an active field of research and, hopefully, higher resolution pictures of supermassive black holes can help to further elucidate their properties.13 Black Hole Universe Theory Ever wonder what it would be like to live in a black hole? You may, in fact, already be doing so. A new theory has been put forth by physicists that suggests that within every black hole, there is a new universe—and the universe that we are currently living in is also the center of a black hole. But how is that possible? To answer that question, imagine the beginnings of the universe. As far as we know, a very small object of impossible density exploded outward in an event known as the Big Bang, and eventually settled and created the universe we know today. But why didn’t the object, being so small and having incredible density,
Figure 3: Another view of the effect of a black hole on spacetime. form a black hole? Actually, it may have. The object in reference can also be known as a singularity, an infinitely small point in space with an impossible amount of matter. Where else in the observable universe do singularities occur? In black holes, at the center of the event horizons. But how did the universe form, and if the universe is a singularity, why is it expanding? To answer this, we must identify a property known as torsion. Torsion occurs when particles with spin interact with spacetime. To understand torsion, imagine that
Letters
Figure 4. The anatomy of a black hole. Jeff, our student, has a flexible rod that represents spacetime. By bending the rod, he can “curve” spacetime; by twisting the rod, he can apply torsion. As particles spin, they create a repulsive force that counters gravitational force, otherwise known as torsion. So let’s apply that information to our early universe singularity. Matter would come together and interact to form new particles that have spins, and thus more particles would interact with spacetime, creating more torsion. As the torsion increased, it would reach a point where it would prevent more matter from coalescing into a point of infinite density, and in fact, have such a strong repulsive force that it would cause the matter to “bounce” away from each other. In fact, this repulsion fits into all models (including dark energy, which is the current explanation to describe the observed acceleration of the expansion of the universe13) and it is a possible explanation for our currently expanding universe.15 So where does that leave us? Every black hole could give birth to a new universe within its event horizon. But that also leaves us with the very humbling knowledge that our universe may be inside a black hole of an even larger universe! Even more interesting is that this larger universe may not even know about our universe. Since we cannot view the information within event horizons on black holes created in our universe, reason states that the larger universe would not be able to peer into our own.15 Our universe is a mysterious place; the more knowledge we uncover, the more mysteries we encounter. And that’s what makes our universe such an exciting place to live in! So go out and enjoy life as a possible Black Holian while gaining an appreciation of the complex workings of the galaxy.
References 1. Black Holes - History. (n.d.). Amazing Space. Retrieved March 8, 2013, from http://amazing-space.stsci.edu/resources/ explorations/blackholes/lesson/whatisit/history.html 2. John Michell and Black Holes. (n.d.).American Museum of Natural History. Retrieved March 8, 2013, from http://www. amnh.org/education/resources/rfl/web/essaybooks/cosmic/ cs_michell.html 3. Felder, G. (n.d.). Bumps and Wiggles: An Introduction to General Relativity. NC State. Retrieved March 8, 2013, from http://www4.ncsu.edu/unity/lockers/users/f/felder/public/ kenny/papers/gr1.html 4. Peter Cole. (n.d.). arizona.edu. Retrieved from http://ircamera. as.arizona.edu/NatSci102/NatSci102/text/lightbend.htm 5. Hawking, S. (n.d.). Into a Black Hole.Stephen Hawking. Retrieved March 8, 2013, from http://www.hawking.org.uk/intoa-black-hole.html 6. Solar mass. WSU. Retrieved from http://astro.wsu.edu/allen/ courses/astr450/summer2012/ 7. A Black Hole Is Born. (n.d.). NCSA Web . Retrieved March 8, 2013, from http://archive.ncsa.illinois.edu/Cyberia/NumRel/ BlackHoleFormation.html 8. UTK. (n.d.). Supermassive black holes. Retrieved from http:// csep10.phys.utk.edu/astr162/lect/active/smblack.html 9. Black Holes. (n.d.). National Radio Astronomy Observatory (NRAO): Look Deeper. Retrieved March 8, 2013, from http:// www.nrao.edu/index.php/learn/science/blackholes 10. Anatomy of A Black Hole. NCSA Web archive. Retrieved March 8, 2013, from http://archive.ncsa.illinois.edu/Cyberia/ NumRel/BlackHoleAnat.html 11. Accretion Disk. (n.d.). Universe Today — Space and astronomy news. Retrieved March 8, 2013, from http://www.universetoday. com/74361/accretion-disk/ 12. Caltech. (n.d.). Redshift. Retrieved from http://coolcosmos. ipac.caltech.edu/cosmic_classroom/cosmic_reference/redshift. html 13. Event Horizon. (n.d.). Universe Today — Space and astronomy news. Retrieved March 8, 2013, from http://www.universetoday. com/42471/event-horizon/ 14. NASA. (n.d.). Dark energy, dark matter. Retrieved from http:// science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/ 15. Poplawski, N. (2012, May 18). Every black hole contains a new universe: A physicist presents a solution to present-day cosmic mysteries. Phys.org. Retrieved March 8, 2013, from http://phys. org/news/2012-05-black-hole-universe-physicist-solution.html Figure 1: http://scienceblogs.com/startswithabang/ files/2012/05/Space-Black-Hole.jpeg Figure 2: http://vacuumsingularity.files.wordpress.com/2010/07/ thft.jpg Figure 3: http://images.dailytech.com/nimage/13298_large_ Black_Hole_Diagram.png Figure 4: http://www.relativitycalculator.com/images/glossary/ black_hole_anatomy.jpg
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Thesis Research
Interview with Danielle Santiago Ramos
Seeking Answers From The Past: Sulfur Extraction of Dolomitized Limestone Ashley “Monty” Montgomery ‘16 Major: Geology Thesis Advisor: Professor David Jones It is a blindingly sunny day in late May of 2012 as four members of the Amherst community hike the Sunnyside mountain range in Nevada. The quartet have a horrible realization as they reach the top: they have run out of water, and have only half of a cucumber as their source of hydration for the hike down. Hurrying down the mountain as quickly as possible while sharing bits of the cucumber is one of the many memories that Amherst College senior Danielle Santiago Ramos has from her geology thesis research. Professor David Jones invited Danielle and two of her fellow geology thesis writers to collect rock samples for a continuation of his research. Professor Jones’ research focuses on finding the cause of a mass extinction event that occurred hundreds of millions of years ago. To this end, Danielle’s research relies heavily on sulfur extraction from rocks in the area where that extinction occurred. Sulfur compositions of these rock samples can tell us much about the oxygenation of sea water. The area where Danielle collected samples was a shallow ocean where organisms lived during the time periods of Ordovician (445.6 million years to 439 million years ago) and Silurian (443.7 million years to 439 million years ago). The mass extinction that occurred between these two intervals resulted in a huge loss in organism diversity. Danielle’s thesis strives to answer the fundamental question of why this extinction occurred through the analysis of the organic material still left—rocks. The sulfur (S2-) that Danielle is analyzing comes from limestone samples in “exposed” (shallow areas close to shore) and “mixing zone” (shallow water mixes with deeper, oceanic water) seawater levels, which now consist of dry rock. Dolomitization is the process in which limestone is at least partially converted to dolomite mineral by way of replacing the original calcite (CaCO3) with, something else—in this instance, seawater. While calcite can be formed from exposure to seawater by precipitating into a solid, Danielle’s samples focus on the calcite formed from organisms’ skeletons, as organisms with shells had calcite skeletons. This type of calcite, where sulfur is incorporated into the calcite as the mineral precipitates, is known as “carbonate-associated sulfate.” Danielle explains that there are several concerns regarding dolomitization, some of which could be relevant to humans. For example, she says, “There is reason to believe that dolomitization changes the pristine (i.e. original) isotopic value of rocks…From rock recording, we can find out if these values were truly pristine or altered. The results of which affect the answer of whether we, as
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human beings, should be worried about dolomitization of rocks in our seawater.” If dolomitization caused the mass extinction event, it could cause a mass extinction now or in the future. We would lose valuable food sources—such as the fish and shellfish that we consume—and have an imbalance in our water’s chemical composition. The process of sulfur extraction entails a few complicated steps. After collecting 400 million year old limestone samples, Danielle must saw the samples, crush the pieces, powder these pieces, and dissolve them with hydrochloric acid (HCl). While the sawing of the material is pretty self-explanatory, to crush her samples, Danielle placed her rocks on a jaw crusher. A jaw crusher is a type of apparatus that uses one set of vertical clamps, with the mineral in between the clamps. While one clamp holds the sample in place, the other moves back and forth, crushing the mineral similar to way a nutcracker cracks a nut. After the rocks are crushed, powdering the sample must be completed. Danielle utilizes a method known as “bulk rock analysis.” After powdering the sample, she can no longer decipher the different layers of rock that existed in the intact sample (the “bulk” in “bulk rock sample”). To do so, she takes the crushed sample to the laboratory at the University of Massachusetts Amherst. Danielle describes the powdering process there as a shadow box shaking her sample “like there’s no tomorrow” for one minute and thirty seconds. The texture of the powdered sample is finer than flour. Finally, the samples must be dissolved with hydrochloric acid. Danielle then adds barium chloride (BaCl2) to her final filtrate in order to get insoluble barium sulfate (BaSO4) to precipitate. From the yield of the barium sulfate precipitate, Danielle finds the composition of sulfate (SO4) and sends samples for testing to the laboratories at Washington University in St. Louis, Missouri to confirm the isotopic composition analysis. Danielle uses the method of mass spectrometry to find the ratio of Sulfur34 to Sulfur32 , the main isotopes in sulfate. Although Danielle is still waiting on trace and major elemental data, she has possible interpretations of the data she has collected on sulfate concentration. “I originally hypothesized that the more
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Thesis Research dolomitization a sample has, the lower the concentration of the sulfate. However, after finally receiving my data, so far, all of my samples have low concentrations of sulfate. Less sulfate doesn’t mean that the remaining sulfate has had its composition changed.
Figure 1: Diversity of marine animal families over geologic time Though the concentration of sulfate decreased by a lot, maybe the isotope composition is still pristine. Right now, this seems to be true... If it is true, my hypothesis is wrong.” Of course, if her hypothesis does happen to be incorrect, Danielle would not be terribly upset. “Data interpretation is not exactly an obstacle because in any case you made a contribution to science…Making sense of the data is also extremely difficult. It’s frustrating…when getting the data back, and it doesn’t exactly tell you whether your hypothesis was correct or not, but of course, it’s all part of the process of being a scientist.” She admits, however, that actually writing her thesis is the biggest obstacle because it takes her “forever.” Danielle’s advice to any aspiring science thesis writer: “Set deadlines for yourself, especially in terms of writing. There is a lot of lab work, but there is a still a lot of writing you can do even when you do not have your data yet—you can write your methodology, your bibliography, introduction, etc.; set clear deadlines and respect them.” If writing was Danielle’s least enjoyable task of her thesis project, then what was her favorite? “I really enjoyed being able to seek answers for myself... As I am trying to figure things out, I have questions that I need to answer…and just being required to do that on my own is fun and really scary at the same time. When you figure it out, you figured it out. Having the sense that I own my
project is the best part.” Working with her advisor—Professor David Jones—was also an enjoyable part of Danielle’s thesis project. “My advisor, Dave Jones, is really funny. Sometimes we [thesis writers] ask questions and he almost answers, but then he’ll be like, ‘No, no. You have to figure that out on your own.’ it’s not a bad thing because then I am forced to find the answer myself. He is available for questions if I drop by, email him, or for weekly lunches…I really admire his research so it’s great working with him.” If she were allowed to make any modifications to her experiment, Danielle agreed that she would. “It would be interesting to do a finer-scale analysis on rocks, and to see if isotopic composition of the cement is different from the allochems (organisms, fossils, etc.). I would also like to compare the sulfate composition in the calcite formed from precipitation in seawater versus the calcite that was part of the organisms. I would need more time and Amherst [College] would need more of the machines necessary for these types of analysis.” Overall though, Danielle seems pleased with her thesis experience. “Field work was tough—our best performance was hiking 150 meters per day and collecting one or two samples for each meter travelled—but great…Doing a thesis is great in getting a sense of how to do my own project. Thesis writing gave me an idea of how it is going to be in graduate school and after that because that’s what scientists do—they have a question, they go into the field, they collect the rocks, do the lab work necessary to answer the questions—and that’s what I hope I will be doing for the rest of my life.” References Figure 1: Holland, S. (2010). Ordovician-silurian extinction. In R. Pallardy & J. Rafferty (Eds.), Encyclopaedia Brittanica. Retrieved from http://www.britannica.com/EBchecked/topic/1523112/ Ordovician-Silurian-extinction Picture of Danielle: Williams, R. (2011, June 01). Student profiles. Amherst Magazine, Retrieved from https://www.amherst.edu/ aboutamherst/magazine/issues/2011summer/nationalinterest/ profiles
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Letters
The Neuroscience of Buddhism
How Meditation Can Change the Brain Emily Jackson ‘13
Figure 1: The Dalai Lama speaks with Amherst alumnus Allan Wallace ’87 at the annual Mind and Life conference in 2004. The other side of the Dalai Lama Few people who have seen the 14th Dalai Lama speak about compassion or Buddhist philosophy would guess the other side of his interests: the exiled spiritual leader has studied scientific fields ranging from subatomic physics to biology, and has spent the last thirty years collaborating with a group dedicated to building a scientific understanding of the mind.1 The idea he shares with other members of the organization, The Mind and Life Institute, is simple. Our brains are complex organs that mediate how we experience the world and how we respond to it, and learning how they work may allow us greater control over both our health and our emotions. A growing field within neuroscience has focused on a phenomenon called neuroplasticity, which is the long-debated ability of our brains to change their wiring and even their structure well into adulthood. The research advocated by the Dalai Lama takes this idea one step further: through our own mental activity, specifically the self-aware control of thoughts and emotions that forms the heart of meditation, he believes that we may be able to literally change the way our brains work. Several recent studies in neuroscience suggest that he may be on to something. Meditation can change the parts of our brain that are active during different mental and emotional situations, with unknown but potentially fascinating implications. If early results hold true, meditation
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may prove to have powerful benefits for our mental lives, with the ability to improve our focus, empathy, and overall happiness. Strange bedfellows: using meditation and MRIs to explore the roots of empathy While any project that involves both science and religion is bound to provoke controversy, two recent studies set examples of how collaboration between them might work. The first study was inspired by previous research showing that the sensation of empathy is closely linked to certain regions of the brain, including the insula cortex and somatosensory cortex. (The insula cortex has been implicated in pain perception and the processing of social emotions2; the somatosensory cortex is also involved in the perception of pain along with touch, temperature and body position.3) Richard Davidson, a collaborator with The Mind and Life Institute, joined with researchers from West Virginia University and
“If early results hold true, meditation may prove to have powerful benefits for our mental lives, with the ability to improve our focus, empathy, and overall happiness.”
Letters the UK’s University of Reading to investigate whether differences in these brain regions could be visualized in Buddhist meditationtrained monks versus in laypeople with only basic instruction in meditation. Using functional magnetic resonance imaging (fMRI) scanners, the brain activity of these monks and laypeople was recorded in response to sounds with positive, negative, and neutral connotations: a baby laughing, a woman in pain, and background noise at a restaurant. All participants were monitored twice, the first time while attempting to meditate, and a second time while at rest. Researchers then looked for differences in brain activity based on three different factors: expert versus novice meditators, being in a state of meditation versus being at rest, and listening to positive, negative or neutral sounds.4 The results they found suggested connections between all three sets of categories. Being in a state of meditation was shown to result in higher overall activation of parts of the insula cortex, regardless of whether the meditators were experts with over 10,000 hours of practice or laymen who had been trained within the last week. Yet compared to novices, experts also showed stronger activity when they heard negative sounds compared to positive sounds, and these changes were more dramatic as the experts switched from meditation to a state of rest. Experts also showed higher activation of parts of another neural circuit that had been previously associated with both reading other people’s mental states and self-reported levels of altruism. What these results tentatively suggest is that mental training, specifically the compassionate meditation commonly practiced by some branches of Buddhism, may be able to change the way our brains respond to the suffering of others and even increase the chance that we will
act altruistically when the time comes. New study, new angle: meditation’s effects on memory and attention A second study offered a similar procedure, comparing the brain activity of trained Buddhist practitioners to that of laypeople, both during compassion-focused meditation sessions and while at rest. Studies unrelated to Buddhism have found that synchronization of neurons, particularly in the so-called “gamma band frequencies,” may be involved in the processes of memory, learning, attention and perceptions. In this second study, longterm meditators showed not only a higher amplitude of gammaband oscillations during meditation compared to laypeople, but also higher baseline levels of gamma synchronization before meditation, implying that mental changes induced by meditation may be more than temporary effects. Trained meditators moreover showed greater evidence of “long-distance gamma synchrony,” a phenomenon that occurs when neurons in different hemispheres of the brain oscillate at the same frequency. This last result suggests an increase in communication between neural networks in different parts of the brain, a phenomenon that is believed to be important for the “highly ordered” thoughts and emotions that characterize a state of attention.5 The researchers cite the gamma activity levels witnessed in several of these monks as “the highest reported in the literature in a non-pathological context.”5 With respect to the Dalai Lama’s intentions, this is an encouraging, if preliminary, finding in support of the potential mental benefits of meditation.
Figure 2 (taken from Lutz et al. 2008): Images from an fMRI scanner show the effects of meditation on the brains of meditation experts and novices. Blue shows a decrease in impulse response, and yellow and orange show an increase (“impulse response” refers to a change in the amount of blood flowing into a region of the brain, which correlates with the activity level of that part of the brain.) Images in each row are taken from the same focal plane, and show several areas of brain activation in experts during meditation that are not seen in novices.
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Letters
“Delving into essential questions about the nature of our minds is likely to yield findings challenging current conceptions of both science and religion, and both fields must be prepared to deal with this possibility.” Controversy and compromise: finding a way forward Yet these intentions raise their own concern: whether the involvement of the Dalai Lama may taint the research he promotes. Richard Davidson, a leading scientist in the field and co-author of both studies discussed above, is also a practicing meditator, though he does not consider himself Buddhist. More importantly, he was invited to the Dalai Lama’s house in India to discuss science with him in 1992, and has remained in close personal contact ever since.6 The friendship is viewed by some as proof that two men respected in their fields can find common ground, yet some scientists worry that the relationship presents a strong conflict of interest—in the blunt yet accurate words of journalist John Geirland, “If Davidson were receiving corporate support to study the effects of ice cream on the brain’s pleasure centers, he wouldn’t hang out with Ben and Jerry.”7 Attempts to unite science and Buddhism have met with wariness from some Buddhists as well. Despite his enthusiasm for the current research, the Dalai Lama was once quoted as saying, after listening to an academic history of the Buddha, “If I believed what you told me…the Buddha would only be a nice person.”8 There are points at which academics and believers will necessarily have different interpretations of an event or observation, and increasing knowledge comes at the price of undermining certain mysteries. Delving into essential questions about the nature of our minds is likely to yield findings challenging current conceptions of both science and religion, and both fields must be prepared to deal with this possibility. The collaboration is still in its early stages, and learning to negotiate the often-fraught lines between science and religion will be an on-going (and likely arduous) process. That said, the quest to reduce human suffering is new to neither science nor Buddhism, and these studies suggest practical and self-directed ways to improve the quality of our lives. Learning how our brains work may show that we have more power over our mental lives than we previously believed, rather than less; and channeling this power, either through meditation or other forms of mental focus, may offer new paths to becoming the people we want to be.
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References 1. His Holiness the 14th Dalai Lama of Tibet. The Office of His Holiness the Dalai Lama. Retr. 26 Nov. 2012. http://dalailama. com. 2. Nieuwenhuys, R. (2012) “The insular cortext: a review.” Progressive Brain Research 195: 123-63. 3. “Somatosensory system.” Wikipedia. Retr. 3 April 2013. http://en.wikipedia.org/wiki/Somatosensory_system. 4. Lutz et al. 2008. “Regulation of the neural circuitry of emotion by compassion meditation: effects of meditative expertise.” PLoS ONE. Vol. 3, 3. Retr. 12 Dec. 2012. http://www.plosone.org/article/ info:doi/10.1371/journal.pone.0001897. 5. Lutz et al. 2004. “Long-term meditators self-induce high-amplitude gamma synchrony during mental practice.” Proceedings of the National Academy of Sciences, Vol. 101: 16369-16373. Retr. 10 Dec. 2012. http://www.pnas.org/content/101/46/16369.long. 6. “Dalai Lama inspires scientist to study happiness.” USA Today. 2010. Retr. 12 Dec. 2012. http://usatoday30.usatoday.com/news/health/2010-05-18-dalai-lama-happiness_N. htm?csp=34news&utm_source=feedburner&utm_ medium=feed&utm_campaign=Feed%3A+usatodayNewsTopStories+(News+-+Top+Stories) 7. Geirland, John. “Buddha on the Brain.” Wired. Feb. 2006. http://www.wired.com/wired/archive/14.02/dalai.html. 8. Lopez, Donald S. Jr. Buddhism and Science: A Guide for the Perplexed. Chicago: University of Chicago, 2008. University of Chicago, 2008.
Thesis Research
My experience of writing a Neuroscience thesis Haneui Bae ‘13 Major: Neuroscience Thesis Advisor: Professor Ethan Graf
My thesis The synapse, the point of connection between two neurons, is the most basic functional element of the nervous system. The synapse is composed of complex protein machinery that mediates neurotransmitter release in the presynaptic terminal and the neurotransmitter detection and intracellular response at the postsynaptic neuron. The Graf lab focuses on the presynaptic side of this exciting process. Rab3, a small GTPase that regulates the synaptic vesicle cycle, has recently been found to play an important role in synaptic organization of the Drosophila melanogaster neuromuscular junction (NMJ). Rab3 mutants showed an altered distribution of the scaffolding protein Bruchpilot (Brp) that led to concentration of Brp at certain release sites leaving other devoid of proper release machinery. Recently, mutants of Rab3-GEF, the guanine-nucleotide exchange factor for Rab3, were also found to exhibit similar synaptic alterations, suggesting its involvement in Rab3-mediated synaptic organization. The goal of my thesis was to investigate this largely unexplored role of Rab3-GEF in synaptic organization by characterizing the Rab3-GEF mutant alleles. I performed a series of genetic rescue experiments with four different transgenic lines. I also examined the site of action of Rab3-GEF by expressing Rab3-GEF::GFP, a GFP-tagged form of Rab3-GEF, and by generating antibodies against Rab3-GEF. Working with Drosophila Easy genetic manipulations Compared to other model organisms, Drosophila allows easier and quicker genetic manipulations because of its short generation time (~10 days from egg to adult fly). In addition, a stash of genetic tools have been developed during its long history as a model organism, making elaborate genetic manipulations possible. Fly genetics is feasible in a smaller undergraduate lab setting like Amherst and provides all the benefits and the learning experience of working in a genetics lab. Mice are another organism commonly used for genetic manipulations. Unlike for a mouse lab, however, fly genetics doesn’t require a giant mouse facility or mouse technician. I made five new fly lines during the fall semester of my thesis, which would not have been possible in a mouse lab. Overall I’m very glad that I worked with flies for my thesis. I was able to
learn the important basics of genetic manipulations in the short time that was available to me. Larval dissection, immunohistochemistry, and confocal imaging If you flip through my thesis, you will find that most of my figures are images—colorful red, green, and yellow pictures of the NMJ. The NMJ and the proteins at the presynaptic terminal are visualized through confocal microscopy. The wandering thirdinstar larvae are dissected to expose the muscles along its body wall and stained with primary antibodies against specific proteins, such as Brp. After being mounted and coverslipped on glass slides, they can be imaged with the confocal microscope. All the images on my thesis were produced after a series of these events. My thesis gave me the opportunity to realize my love of imaging. Imaging takes a long time from beginning to end, but for me, seeing the beautiful final product was completely worth the numerous shivering all-nighters in the confocal room.
Fly lab habits: You know you’re working in a fly lab when … You start using the word “Drosophila” to say “fruit flies.” (Swatting the flies away, darn these Drosophila!) And your friends get used to you saying, “I gotta go collect virgins,” several times during the day. Advice to Future Thesis Writers Write a mock results section When I was interviewing thesis writers last year for last year’s issues of the Element, they always advised me to finish the introduction in the fall. Yes, I will be a great student and finish my introduction in the fall, I thought to myself. Of course, this did not happen as planned, and in my extreme case, the introduction turned out to be the last section I finished (yes, even later than
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Thesis Research results or discussion). The introduction was the hardest section for me to write, because it required so much reading and integration of knowledge from numerous different sources, so I found myself pushing it away till the last minute. If you have trouble working on your introduction like I did, I suggest you try writing a “mock” results section. When I started getting some data, I wrote up an outline for my results section, which included where I would put certain figures and graphs. A good results section tells a story, starting from your initial hypothesis, to additional questions as you progress further into your thesis. Writing up an outline for results, or “mock” results as I would call it, lets you get a firmer grasp of where your thesis is headed and what parts of your story it is still missing. Of course this will be edited substantially as you start collecting real data (and trust me it will be very different from what you initially expect), but this will help you get started on thinking about your project in a more constructive way.
When I first saw my quantification data for the rescue experiments I started panicking. They were not what I initially expected at all, and I thought that I must have done something completely wrong. Professor Graf helped me calm down and reminded me: data are data. Whether negative results or positive, your data never lie. We sat down together in front of the computer staring at the graphs I generated from my data. We soon found consistent patterns from what initially seemed like a random jumble of events. And these consistencies had very interesting implications about the role of Rab3-GEF that have not been shown before. When I wrote up a discussion of my results a few nights later, it was the most intellectually stimulating night of my entire Amherst life. Further experiments are still necessary to confirm my findings, and many of my potential explanations may turn out to be false. But that night I could catch a glimpse of what it was like to be a scientist, carefully reading and interpreting the uncharted waters. Undoubtedly you will run into completely unexpected results throughout your thesis. In those cases, don’t panic. Have confidence in your data. My thesis taught me not to be scared of unexpected data because that’s how discovery starts.
Have confidence in your data
Figure 1: Apposition of Brp puncta and GluRC clusters at the NMJ. Brp is the scaffolding protein in the presynaptic terminal and GluRC is a glutamate receptor subunit in the postsynaptic muscle. At the WT (wild-type) NMJ, Brp puncta are small and almost completely apposed by GluRC clusters. However, in rab3 mutants (rab3rup), Brp is concentrated at only a small fraction of available sites, creating larger, brighter, and fewer puncta. rab3-GEF mutants (MA15 and MA20) show a hypomorphic phenotype, showing similar but less severe alterations of the Brp distribution. The postsynaptic organization is largely unchanged.
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Letters
Eye in the sky Lindsey Bechen ‘16
How often is it that you miss a once in a lifetime event simply because you didn’t know it was happening? Or do you always forget about annual events because once you remember, it’s too late? Well, here’s a quick summary of all the most important astronomical events happening for the rest of this year, so you can be sure not to miss them! In this article, we will focus on events that can be seen in the continental United States; if you are in other parts of the world, they may not be visible. Many astronomical events are easy to view with little or no special equipment. Although most of the events described in this article can be seen with the naked eye, other gear such as a small telescope may increase their visibility. Much of the time, a specific area of the sky will be the focal point of the event. In these cases, constellations are used to indicate which area you should be looking toward. If you are not familiar with constellations already, there are many online sources that provide maps of the sky to use. (See stellarium.org and skyandtelescope.com for two fantastic, free interactive sky maps.) Meteor Showers On an average night, there are usually a few scattered meteors per hour. However, when the earth’s orbit intercepts an area of rough debris leftover from a comet or other source, this rate can shoot up into the range of dozens or more per hour. These showers usually have a peak time and radiate from a single point in the sky. The best viewing conditions are on a clear night with no light pollution from the moon or other sources.1 There are many annual meteor showers that you can view each year; however, this year is particularly bad for viewing, as nearly full moons on the nights of the peaks will drown out the weaker meteors. I have listed here the showers that show the greatest chance for a good viewing: The Eta Aquarids peak in the early hours of May 5th, radiating from the constellation Aquarius. The shower is caused by leftover debris from Halley’s Comet, and the rate of meteors could reach from twenty to forty an hour. While the rate does not make it the most notable of showers, the moon does not cause a viewing problem like other showers this year, so you shouldn’t miss it!1 The June Boötids offer anywhere from ten to forty meteors per hour. However, the shower is likely to be worth seeing this year since the moon will only drown out late-night viewing. The shower will peak late in the evening on June 27th, and will radiate from the constellation Boötes.1 The Perseids are likely to be the best shower for viewing this year. In addition to having an hourly rate that can reach over
sixty per hour, the moon will set approximately when the shower starts. This will leave the sky dark enough to view even the dimmer meteors. The shower will radiate from Perseus, peaking the night of August 11th through the morning of the 12th.1 The Geminids are usually the best shower of the year, reaching up to one hundred meteors per hour. Unfortunately, the moon will be nearly full during the peak this year. Because of its high frequency, however, you may still be able to see the brightest meteors. The shower will peak on the night of December 13th, radiating from Gemini.1
Figure 1: A Leonid Meteor during the 2009 shower.
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Letters Eclipses Eclipses are a result of the sun, moon, and earth being in exactly the right alignment at the right time of year. There are two types: solar and lunar. A lunar eclipse occurs when the moon passes into the earth’s shadow, causing the moon to appear a rusty red. A solar eclipse occurs when the moon passes between the sun and earth, either totally or partially covering the sun.2 Lunar Eclipses: Two lunar eclipses are visible from North America this year. Unfortunately, both are penumbral, meaning the moon only dips slightly into the earth’s shadow. The first one occurring on May 25th will be barely visible, but the eclipse on October 18th is likely to tint the moon red on its southern part. 2 Solar Eclipses: On November 3rd a rare hybrid solar eclipse will occur, meaning that it will start as an annular eclipse (an eclipse in which the moon only covers the middle of the sun, creating a ring of sunlight) and end as a total eclipse.2,7 Unfortunately, the east coast of the US is right on the easternmost border, making it unlikely that any eclipse is to be seen at all. However, if weather conditions are right, you might be able to catch a glimpse. Just be sure to have adequate eye protection (sunglasses don’t count).2 You can either use special eclipse viewing glasses which prevent eye damage by filtering out ultraviolet radiation, or use a piece of cardboard with a small hole punched in it to project an image of the sun for indirect viewing.7
Figure 3: A diagram depicting the pinhole projection method of viewing a solar eclipse.
Figure 2: Total Lunar Eclipse.
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Letters
Figure 4: Comet McNaught over the Pacific. Comets Comets appear in the sky as long-tailed stars. In reality, they are chunks of ice with frozen gases, rock, and dust embedded in their surface. As a comet approaches the sun, it heats up and develops an atmosphere consisting of the gases from the heated ice, known as a coma. What appears to be the comet’s tail is actually its coma being blown back. There are two types of comets: long and short period. Many long-period comets arise from an area called the Oort Cloud and can take as long as thirty million years to orbit the sun. Short-period comets mostly originate from the Kuiper Belt just beyond Neptune, and take only about two hundred years to orbit the sun.3 Comet ISON is a long-period comet making its first trip into our solar system, meaning that its surface is likely to still contain fresh volatiles.4 The comet will be closest to the sun on November 28th. If it survives this encounter, it could prove to be one of the brightest objects in the sky.5 The comet should be visible starting in October extending through December.5,6 Conclusion It’s impossible to include every event happening in the next year, especially because scientists cannot easily and accurately predict many of them. You may want to keep a watch on the news to see if any of these dates have changed or if other significant events will occur. But next time you’re outside, find a quiet dark spot and take a look at the sky. (Great viewing places around Amherst include Memorial Hill and the Bird Sanctuary.) It’s
through occurrences like these that we all can gain a greater appreciation for the universe in which we live. References 1. Beatty, J. K. (2013, Jan 2). Meteor Showers in 2013. Retrieved from http://www.skyandtelescope.com/observing/objects/ meteors/Meteor-Showers-in-2013-185454662.html 2. Beatty, J. K. (2013, Jan 5). Eclipses in 2013. Retrieved from http://www.skyandtelescope.com/observing/objects/eclipses/ Eclipses-in-2013-191945241.html 3. (2013, Mar 8). Comets: Read More. Retrieved from http:// solarsystem.nasa.gov/planets/profile.cfm?Object=Comets&Disp lay=OverviewLong 4. Agle, D. C., & Brown, D. (2013, Feb 5). NASA’s Deep Impact Spacecraft Eyes Comet ISON. Retrieved from http://www.nasa. gov/mission_pages/asteroids/news/asteroid20130205.html 5. (n.d.). Astronomy Calendar of Celestial Events for Calendar Year 2013. Retrieved from http://www.seasky.org/astronomy/ astronomy-calendar-current.html 6. Malik, T. (2013, Feb 6). NASA Probe Snaps Photos of Potential ‘Comet of the Century’. Retrieved from http://www.space. com/19656-comet-ison-nasa-spacecraft-photos.html 7. Fazekas, A. (2012, May 20). Solar Eclipse 2012: How to See “Ring of Fire” May 20. Retrieved from http://news.nationalgeographic. com/news/2012/05/120520-solar-eclipse-2012-ring-of-fireannular-sun-science-how-see-where/ The Amherst Element, Vol 5, Issue 2. Spring 2013
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