Spring 2011 Issue

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Carolina Scientific

Spring 2011, Volume III Issue II

sc1ent1ficcarolina Undergraduate Magazine UNC-Chapel Hill

Spring 2011 Volume III, Issue II

Copyright © 2004 Richard Ling

Carolina Scientific

Spring 2011, Volume III Issue II 2

From the Editors:This year, we are thrilled to be a part of Carolina Scientific’s new leadership, passed on to us from the former editors and founders of the magazine. We have watched it grow from an idea into a full-fledged publication, and we hope you find that we’ve carried on Carolina Scientific’s mission statement to the fullest—to provide an interesting and informative collection of campus-wide research. We have enjoyed watching our staff tackle challenging scientific material, and hope that their passion for research and science shines through in their pieces. Enjoy!

Rebecca S., Garrick, Rebecca H., and Rohan

Mission Statement:Founded in Spring 2008, Carolina Scientific serves to educate undergraduates by focusing on the exciting innovations in science and current research that are taking place at UNC-CH. Carolina Scientific strives to provide a way for students to discover and express their knowledge of new scientific advances, to encourage students to explore and report on the latest scientific research at UNC-CH, and educate and inform readers while promoting interest in science and research.

(From left to right)Rebecca Searles, Editor-in-Chief and Biology Editor, is a senior Biology

and Psychology double major.

Garrick Talmage, Chemistry Editor, is a junior Biochemistry major and

Biology and Math minor.

Rebecca Holmes, Physics Editor, is a senior Physics major.

Rohan Shah, Production Editor, is a senior Biology major and Chemistry

minor.

Special thanks to our 2011 Carolina Scientific Production Staff!

(From left to right)Janitra Venkatesan

Kati MooreKristen Rosano

Hema Chagarlamudi

Contact us at [email protected].

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Table of Contents

4 When Smaller is Better: Human Immune System Studies in Mice

Darya Gakh

6 It All Comes Down to SweatDoug Lange

8 Heating Up the Evolution DebateHetali Lodaya

10 Thirty-Two Bottles of Coke and Twenty Feet of Intestine

Kara Stout

12 Some Like It Hot: Extreme Microbes in the Guaymas Basin

Kelly Speare

14 The Coral Conundrum Kelsey Ellis

16 A Synthetic Substitute Delivers More Than Blood

Kristen Rosano

18 Plant Organ Donation: Shedding for a Good Cause

Lindsay Ross

20 The Mystery Of The Deep: Inside The PlumeMaggie Hunter

22 Antibiotics Making a Comeback Nabila Sarki

24 Thinking Positively About Restoration And Conservation in Aquatic Communities

Patrick Fox

26 Cutting Carbs Just Won’t Cut It: Investigating the Influence of

Genetics on Metabolic Function Kristine Chambers

28 The Secret to Skunking Connie Wang

30 The Greater Meaning of Global Warming Kati Moore

32 Mind-Body Interdependencies “Positively” Influence Well-Being

Jana Lembke

34 The Physicist’s Playground Matt Dutra

36 The Game of Telephone and AnAnalysis of Signal Detection in Animals

Madison Roche

38 Astronomical Kingdom Apurva Oza

Carolina Scientific


They eat your cheese. They scare your elephants. Usually found in bundles of four or more, mice are clean creatures despite their

reputation [1]. Better yet, they may help provide the cure to human diseases such as Hepatits B Virus (HBV), Hepatitis C Virus (HCV), and even Human Immunodeficiency Virus (HIV). Not so scary after all. Lishan Su’s lab is the first to use mice to develop a small animal model with a human immune system for

studies of HBV and HCV [2]. HCV is an infectious disease that affects the liver through reoccurring infections that cause scarring of this tissue. It is estimated that 270-300 million people worldwide are infected with HCV, and no vaccine is currently

available. HCV generally starts out in an acute stage, during which symptoms resemble the flu. However, in most cases this acute stage progresses into a chronic stage, whereupon it has been present in the body for over six months. Over 175 million people are chronically infected by HCV, often resulting in hepatitis, liver fibrosis, cirrhosis and development of hepatocellular carcinoma [3]. Chloe Greguska, a junior biology major at the University of North Carolina, is helping optimize the

study of HCV on these mouse models. In order to give these immunodeficient animal models human immune systems, the mice must first be made liver deficient. This is done by killing their liver cells by expressing the FK506 binding protein under control

When Smaller Is Better: Human Immune System Studies in Mice

Figure 1. Approximately 99 percent of human genes have counterparts in the mouse. Out of the 30,000 genes in both the mouse and human genomes, only about 300 are unique to either.

Darya Gakh, Staff Writer

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of the albumin promoter (AFC8) and then injecting human liver stem cells into the mice [3]. This has finally proven successful and is detailed in a paper recently published by the team. The Su lab is working toward understanding how these diseases interact with the immune system. In order to do this, they are infecting the mice models with HCV, and then taking blood samples to examine how the human immune cells have responded to HCV infection. It is important to note that, while this procedure puts human cells into the mouse, only about 20 percent of the cells in the chimeric liver are human. After taking blood samples, the number of mouse cells and human cells is counted and then the human cells are used for further analysis [4]. One of the projects that Chloe Greguska is working on attempts to improve the 20 percent reconstitution rate. This is done using several methods, one of which involves using oncogenes. Oncogenes are genes which can cause cells undergoing apoptosis, programmed cell death, to survive and grow instead. The use of these oncogenes can frequently lead to cancer, causing difficulties for HCV infection. However, this allows for the possibility of liver cancer research, another area of research the Su lab hopes to work on. The Su lab also examines HIV. Through the use of the mouse model, they are working on being able to examine how HIV infection leads to immunodeficiency or AIDS. Furthermore, the Su lab is simultaneously working to see how HIV and HCV co-infect cells. It has been found that when HCV and HIV infect patients simultaneously, the liver disease progresses very rapidly. For the first time, there is a mouse model that can simulate the co-infection of these diseases [5].

Su says that one of the most interesting things he found in his research is the “ability to manipulate the human immune system in human stem cell development and the ability to generate any human tissue in immune deficient mice” [5]. Further studies can look into how human viruses can be transmitted to these mice models and how the mouse’s human immune system will react to this. These little creatures hold the key to examining immune system responses in prevalent human diseases. So next time you see a mouse in your house, give it some cheese and avoid the mouse traps, because it may someday save your life [6].

References1. Interview with Lishan Su, Ph.D. 02/11/112. Bruno S, Facciotto C. Ann Hepatol 2008;7:114-93. Su, Lishan, et al. Gastroenterology. 2011 4. Interview with Chloe Greguska. 02/12/11

Darya Gakh is a junior Biochemistry major and Spanish minor.

Though frightening for some, the common house mouse, mus musculus, has one of the most valu-able genomes for human disease research.

Carolina Scientific


Sweat is just a foul-smelling annoyance to most people, a regulatory body-function that we put

up with day-to-day. But if you’re the parent of a baby that just came up positive on a newborn screen-ing test for cystic fibrosis (CF), sweat just got a lot more important. CF is a genetic disorder that affects about 2500 newborns every year in the USA. CF is caused by a mutation in the gene for CFTR, a protein that acts primarily as a channel for chloride to flow through. People with CF excrete abnormally large amounts of chlorine and sodium in their sweat [1]. This is the

basis for sweat tests performed on newborns to ex-amine for increased salt concentration. CF is a serious disorder, so early diagnosis is cru-cial in order to allow patients to receive treatment as soon as possible. Because of this, Dr. Vicky LeGrys, faculty member of the division of Clinical Labora-tory Science at UNC, has been researching ways to decrease erroneous results obtained by sweat tests. She has worked with national and international com-mittees to establish written standards for sweat test-ing and has implemented proficiency testing in labo-ratories. Recently, LeGrys obtained records from the

Figure 1. A pediatrician administers a cystic fibrosis sweat test to a baby. Dr. Vicky LeGrys of the Clinical Labora-tory Science division at UNC studies the reliability of these tests.

Doug Lange, Staff Writer

It All Comes Down to Sweat

from Johns Hopkins CF center website.

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115 labs in the country that are accredited by the CF Foundation to offer sweat tests and examined the percentage of tests that yielded an insufficient vol-ume of sweat for analysis, an indication for perfor-mance. From this data LeGrys learned two important things about the sweat test: the method for collecting the sweat did not affect the number of insufficient tests and there was a huge variability in the percent-age of insufficient tests across CF centers, ranging from 0-40%. This large range on a relatively con-stant population was collection method independent and allowed LeGrys to infer that the variability was related to operator error in the laboratory [2]. LeGrys used this data to set a benchmark for per-formance for quality improvement. Laboratories should achieve a sufficient volume for testing more than 90% of the time in patients less than 3 months of age [2]. “You are confirming the diagnosis of a lethal dis-ease. Therefore it is of the utmost importance it is done as accurately as possible,” says LeGrys. All 115 labs are monitored annually and are visited ev-ery 5 years to make sure they remain in compliance with written laboratory standards. Dr. LeGrys fre-quently visits clinical laboratories nationwide and internationally to evaluate operator performance of the sweat test and to develop quality improvement initiatives [2].

CF may be a fatal illness, but thanks to modern medicine and early treatment the average life span of CF patients is steadily increasing. Sure, sweat might not seem important to most of us from day to day, but to some it all comes down to sweat.

References1. D. Zieve, et al. Cystic Fibrosis. 2010, 5, 101.2. Interview with Dr. Vicky LeGrys, Ph.D. 02/21/10.

Figure 2. Computer representation of CFTR gene. Figure 3. Illustration of 2 CFTR proteins.

Doug Lange is a junior Clinical Laboratory Science major.

Wikipedia commons, posted on March 10, 2009 by donabelsdsu.bot From the University of Utah cystic fibrosis webpage.

Carolina Scientific


It is a simple debate that has raged for centuries: creation or evolution? A common creationist argument centers on the time required for life to

evolve. The world has simply not been around long enough, creationists argue, for simple bacteria to evolve into complex life forms like humans without the help of a creator [1]. In addition, many essential biological reactions as they are understood today cannot progress properly without the help of a catalyst — it would take significant amounts of time, creationists say, for these catalysts to become widespread. Understanding this problem requires looking at rates of reactions and temperatures at which they oc-cur, especially when the reactions are uncatalyzed. It is likely that many of the reactions integral to the development of life originally occurred without the help of enzymes, resulting in slow rates overall until appropriate enzyme catalysts evolved. The general ‘rule of thumb’ for chemists is that a 10° C increase in temperature will double a reaction rate [2]. Under this assumption, even a very warm primordial earth would have had little effect on reactions whose uncat-alyzed half-lives are, in some cases, millions of years. The Wolfenden group at UNC-Chapel Hill recently published research on slow reactions that challenges this assumption [3]. Reaction rates were measured and extrapolated for several biological processes

that, uncatalyzed, take very long to progress. Accord-ing to the established chemical theory, a temperature change from 25 °C to 100 °C, for instance, should cause about a 70-fold increase in rate for a typical reaction. This prediction is based on the iodine clock reaction, and can be found in chemistry textbooks and lab manuals across the world. As shown in Table 1, almost all of the biological reactions studied were

found to experience much greater increases in rate than the iodine clock reac-tion with this same tem-perature change. It is also important to note that the slowest reactions experi-enced the greatest increase in rate. This creates a lev-eling effect—reactions that are slow experience greater gains in speed with tem-perature, allowing them to ‘keep up’ with fast reactions.

Hetali Lodaya, Staff Writer

Table 1. Temperature effects on the rates of reactions without catalysts. As half-lives increase, the ratio of equilibrium constants k100° and k25° increases, showing that the same increase in temperature will increase the rate of a slow reaction much more than the rate of a fast reaction.

Figure 1. Projected change in rate for an enzyme that lowers entropy of activation, TΔS (left) versus one that lowers enthalpy of activation, ΔH (right).

Used with the permission of Dr. Wolfenden.

Figure 1 used with the permission of Dr. Wolfenden.

Heating Up the Evolution Debate

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These reaction rates collapse the time needed for life to evolve even on a slightly warmer primordial Earth by as much as five orders of magnitude—ac-cording to Professor Wolfenden, “it is a new way of looking at the early evolution of life.” [4] Ad-ditional evidence comes from the group’s study of several proto-enzymes, small molecules that prob-ably evolved to become the first biological cata-lysts. A rate can be increased by either changing the enthalpy of activation, ΔH, or entropy of acti-vation, TΔS. As shown in Figure 1, only a catalyst that affected ΔH would have a significant effect on rate—the rate change is much more pronounced for these catalysts as k changes. Proto-enzymes were studied to understand which pathway they use to increase reaction rate; the group’s results strongly suggest that they all use the enthalpic mechanism. Under this model, rate enhancement actually in-creases as temperature decreases (Figure 1). Essen-tially, the compounds believed to be nature’s earliest catalysts actually function better at lower tempera-tures. This suggests that as the Earth cooled, these enzymes flourished and were evolutionarily favored. Geological evidence indicates that life appeared on Earth almost as soon as the oceans were formed, but scientists have yet to unravel the mystery of ex-actly what events led to life as we know it today. The Wolfenden group’s findings lend support to a hot,

wet early Earth where bio-logical reactions occurred unassisted, sped up by the temperature of their sur-roundings. As the Earth cooled, catalysts slow-ly evolved that worked faster and faster despite the decrease in tempera-ture, maintaining a pace that explains the speed with which life forms be-came more complex [3]. “Physical organic chem-istry is what it is, and the possibility that it has im-plications for evolution is wonderful, and startling,” states Professor Wolfen-den [4]. The creation-evolution debate is far

from over, but the Wolfenden work on the relation-ship between temperature and reaction rates throws a new piece of evidence into the primordial mix.

References1. Ball, Phillip. Some Like it Hot. 2010, <http://www.nature.com/news/2010/081110/full/news.2010.590.html>.2. Chin, Gilbert. 2011, <http://www.sciencemag.org/content/331/6013/11.4.full>. 3. Stockbridge et al. Proc. Natl Acad. Sci. 2010, 107, 22102-22105. 4. Interview with Richard Wolfenden, Ph.D., 02/09/11.

Figure 2. Fossilized evidence of stromatolites from about 1 billion years ago.

Credit: By P. Carrara, NPS [Public domain], via Wikimedia Commons

Hetali Lodaya is a freshman Biochemis-try major.

Carolina Scientific


Kara Stout, Staff Writer

Every day 11.5 liters of ingested food and digestive juices pass through the digestive system—the equivalent of over 32 bottles of

coke [1]. Food is passed through the 20 feet of small intestine that connects the stomach to the colon, which will complete more than 90% of the digestion and absorption using bile and pancreatic juices (Figure 1)[2]. Every four days the epithelial lining is completely replaced due to damage caused by the chemical and mechanical abuse of the contents it is digesting [3]. A growing area of research that I am involved in is the study of the intestinal stem cells (ISCs) that replenish the damaged epithelial lining. The small intestine is divided into the three re-gions based upon their proximity to the stomach: the duodenum, jejunum, and ileum (Figure 1). How-ever, the fundamental unit of the small intestine is the crypt-villus axis (Figure 2). Villi are cellular projections into the intestinal lumen that provide an increased surface area available for digestion. Be-tween the villi are invaginations called the crypts of Lieberkuhn, which are covered in epithelial cells. At the base of the crypts are the ISCs, which are con-stantly dividing to replenish cells in the crypt. ISCs produce four types of cells: enterocytes, which aid in digestion and absorption, goblet cells that se-crete mucin which forms mucus, enteroendocrine

cells, which secrete hormones important to the gas-trointestinal system, and Paneth cells that defend against microbes [3]. These cells continue to divide as they mature and migrate up the villi (Figure 2). Dr. Henning at UNC-Chapel Hill wants to iden-tify and isolate ISCs based on specific markers on the surface of cells. This separation is done through a process called fluorescence-activated cell sort-ing (FACS), where particular cells are isolated based upon the fluorescence and light scattering ability of each cell [4]. Antibodies against certain cell markers are conjugated to small fluorescent molecules, and cells are stained with a cocktail of different fluorescent antibodies. CD24, a mem-brane protein, is a good candidate to be a stem cell marker, and its presence has been confirmed in the crypt base by an immunohistochemical staining with the CD24 antibody (Figure 3). CD24 func-tions in cell-cell and cell-matrix adhesion as well as extracellular-to-intracellular signal transduction. Because of this adhesive characteristic, CD24 may be key to anchoring ISCs into the base of the crypt. To isolate CD24+ stem cells from other cells dur-ing FACS, an anti-CD45 antibody was used to ex-clude hematopoietic stem cells, which produce all of

Figure 2. Crypt-Villus axis labeling the 4 primary cell types in the intestinal epithelium.

Figure 1. Basic anatomy of the digestive tract.

Thirty-two Bottles of Coke and Twenty Feet of Intestine

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the blood cell types. To confirm the CD24+CD45- allotment was indeed stem cells (Figure 4), other accepted stem cell markers, Lgr5 and Bmi1 were used [4]. This population showed a 40-fold enrich-ment of the marker Lgr5 and 5-fold enrichment of Bmi1, indicating the presence of stem cells [4]. I am researching the therapeutic potential of these

isolated stem cells in the base of the crypt to replenish the four cell types located in the intestinal epithelium. Intestinal stem cells may have significant potential in the treatment of gastrointestinal disorders. They could be used to regenerate function in the small intestine inhibited in diseases such as short bowel syndrome, inflammatory bowel disease, or following irradiation.

References1. Digestive System Function Facts. 2011. <http://library.thinkquest.org/J0112205/ interesting_facts.htm>.2. The Human Intestines: Function, Body Location, Shape, Definition, and Disease. 2011. <.http://www.mamashealth.com/organs/intestine.asp>.3. A. Shaker, et al. Translational Res. 2010, 3, 180-187.4. R. Furstenberg, et al. Am. J Physiol. Gastrointest. Liver Physiol. 2010. 5. Stem Cell Basics. 2009. <http://stemcells.nih.gov/info/basics/basics6.asp>.

Figure 3. Mouse jejunum stained with CD24 antibody at low (A) and high (B) power.

Figure 4. Flow cytometric identification of the CD24+CD45- gated fraction in the circled region, indicating the presence of stem cells in this population of jejunal epithelium.

Kara Stout is a junior Biol-ogy and Global Studies major, and Mandarin Chinese minor.

Carolina Scientific


After an hour-long descent huddled in a frigid 3-man vessel, headlights illuminate a foreign deep-sea world out of the pitch-

dark water. Scientists aboard the Alvin submersible

journey over 2,000 meters down to the seafloor to study the otherworldly home of extreme microbial communities in the Guaymas Basin. Dr. Barbara MacGregor and collaborators from the Department of Marine Sciences study a unique system of hy-drothermal vents that provide an energy source for microorganisms in this otherwise desolate and un-inhabitable environment [1]. Understanding hydro-thermal vent systems is important to the study of microbiology, because they provide a way to hypoth-

esize about the possible origins of life on earth [2]. The Guaymas Basin in the Gulf of California (Fig-ure 1) is situated on an area of transform faults, cre-ated by the separation of the Pacific and North Amer-ican tectonic plates. However, Guaymas is unique from other spreading centers, because it experiences high rates of sedimentation that blanket the seafloor, preventing volcanic activity that is characteristic of most spreading centers [1,3,4]. As the Earth’s crust separates, seawater seeps down into crevices, is hy-drothermally heated, and forced back up through hundreds of meters of organic-rich sediment, creat-ing a variety of hot-water vents [4]. These hydrother-mal vents supply the seafloor with a hot-water cock-tail, rich in dissolved gasses such as methane, carbon dioxide, and hydrogen sulfide. Chemosynthetic organisms from all three domains of life, Bacteria, Archaea, and Eukarya, utilize this harsh, but chemi-

Figure 1. A map of the Guaymas Basin, which is a unique spreading center situated between mainland Mexico and the Gulf of California.

Figure 2. The robotic arm of the Alvin submersible tak-ing a temperature reading in a mat of orange, yellow, and white Beggiatoa.

Kelly Speare, Staff Writer

Some Like it Hot: Extreme Microbes in the Guaymas Basin

PC: L.G. Alvarez, et al. Boletín De La Sociedad Gológica Mexicana. 2009, 61, 129-141.

Photo courtesy of http://4dgeo.whoi.edu/alvin.

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cally rich environment [4]. Additionally, petroleum production is catalyzed by the combination of heat and organic-rich sediments, creating small pockets of petroleum that seep up through the sediment [3]. Microbes living in Guaymas sediments have two forms of energy sources to choose from: organic compounds in the sediment that are derived from photosynthetic production such as petroleum, or hy-drothermally processed compounds [3]. Dr. Barbara MacGregor and other scientists from the Department of Marine Sciences are studying the microbial commu-nity in the Guaymas sediment in an effort to determine what these microbes use as their carbon source, and how they interact with these hydrothermal processes. Dr. MacGregor traveled to the Guaymas Basin in 2008 and 2009 to collect sediment samples using the Alvin submersible (Figure 3). Particularly interesting are the brightly-colored giant bacteria, Beggiatoa, that grow in filamentous mats which highlight areas of hydrothermal activity (Figure 2). These enormous, yellow, orange, or white, sulfide-oxidizing bacteria

live atop sediment that is home to communities of bacteria and archaea. Beggiatoa only live on the sur-face of the sediment because they require oxygen to oxidize sulfide. However, microbes living in the an-oxic sediment are able to metabolize anaerobically [3]. These microbes produce dissolved gasses such as methane metabolically, in addition to the natural production of gasses in the hydrothermal system [3]. Dr. MacGregor is using stable carbon isotope ratios to trace the flow of carbon through the hy-drothermal system, in order to determine what the microbes are using as their carbon source. RNA pro-vides a unique way to study carbon flow, because it can be used to link the identity of an organism to its carbon source. The carbon signature of the substrate that the microbes are metabolizing should be reflect-ed in the stable carbon isotope ratio of their RNA [3]. As scientists gain a better understanding of micro-bial hydrothermal vent communities and how they derive their energy, they are better able to hypothesize about early life on earth [2]. To visit extreme micro-bial habitats such as the Guaymas Basin, scientists must climb into a state-of-the-art submersible able to withstand the severe temperature and pressure chang-es when traveling to the deep. However, microbes such as Beggiatoa thrive here; their adaptations to the unique Guaymas Basin environment are fascinating to scientists and invaluable to the field of microbiology.

References1. Dive and Discover. 2011, <http://www.divediscover.whoi.edu/expedition1/index.html>.2. W. Martin, et al. Nature Reviews Microbiology. 2008, 805.3. Interview with Dr. Barbara MacGregor, Ph.D, 2/13/10.4. A.P. Teske, et al. Appl Environ Microbiol. 2002. 68(4): 1994–2007

Kelly Speare is a sophomore Biology major and Marine Sciences minor.

Figure 3. The Alvin submersible being lowered into the water off the deck of the Research Vessel Atlantis.

Photo courtesy of Tingting Yang.

Carolina Scientific


Kelsey Ellis, Staff Writer

Coral reefs are notoriously delicate ecosystems, easily affected by climate change, ocean warming, nutrient and sediment pollution,

and overfishing [1]. In the twenty-first century, their fragility has become a symbol for the environmental degradation created by our overuse of natural resources. In recent years coral reef scientists interested in reef conservation have studied the effects of these anthropogenic changes on reefs. One of these scientists, Dr. John Bruno of the Marine Sciences department, has collaborated with other researchers to study a widespread reef phenomenon: the transition of a human-disturbed reef from

traditional coral dominance to macroalgal dominance. Through observation and analysis of case studies, Dr. Bruno has developed an explanation for these changes that holds implications for the way coral reef conservation is will be approached in the future. Many of the world’s coral reefs have been com-pletely altered within our lifetimes. Back in the1970’s, Dr. Bruno remembers “snorkeling on relatively pristine reefs with big golden fields of coral and hammerhead sharks circling and…it was just fantastic” [1]. But in the intervening years, many coral reefs have experienced large increases in algae growth and in some cases have become algae-dominated [2]. What Dr. Bruno has been researching is whether these changes represent an environmental phase shift or are alternative stable states for the ecosystem. A phase shift occurs in response to a change in an environmental variable and results in the ecosystem favoring a different kind of organism, in this case macroalgae over coral. An alternative stable state, on the other hand, is a biological community that has been completely changed by an outside disturbance [2]. At first glance these concepts might seem similar, but the point of Dr. Bruno’s research has been to reiterate the subtle but important differences between

Figure 1. Coral reefs like this one, located in the Great Barrier Reef, are becoming increasingly rare as the impact of humans on the ocean increases.

Figure 2. An example of a coral-dominated reef.

THE CORAL CONUNDRUM

Source: U.S Fish and Wildlife Service WO-3540 CD42A, author Jerry Reid

Source: rling.com, Richard Ling.

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phase shifts and alternative stable states in coralreefs. While a phase shift in a community can be reversed if the environmental variable that caused the shift in the first place is removed or changed, a community in an alternative stable state becomes locked in place by a series of positive feedbacks [1]. The prevailing viewpoint in coral reef ecology has been to see the change towards macroalgal domination as an alternative stable state, but Dr. Bruno’s research challenges this theory. To determine the nature of the macroalgal invasion, Dr. Bruno and his colleagues examined case studies that had previously been proffered as examples of coral reef alternative stable states. Data from reefs off the coasts of Australia, Jamaica, Panama, and Hawaii where the reefs became macroalgae-dominated was gathered and analyzed.

What Dr. Bruno found was that, though reefs become microalgal in response to disturbances in climate, ocean temperature, pollution, and overfishing, these changes reversed themselves in the absence of the environmental variable that triggered them [2]. This led Dr. Bruno to conclude that for the most part, the macroalgal domination of reefs represents a phase shift rather than an alternative stable state. This is an important realization because, as Dr. Bruno stated, “we need to know what has causedthe change in order to be able to address it” [1]. The discovery that the macroalgae invasion is a phaseshift is a hopeful one, since it means that reefs can be restored to their former states by removing thechronic stresses that put them there in the first place. Unfortunately, because of the increasing pressuresbeing put on coral reef ecosystems by human activities, this is no simple task. What Dr. Bruno and hiscolleagues propose in light of this new information is to focus on figuring out what variables killed the coralin the first place, and to take steps towards coral restoration through the reintroduction of overfishedmarine herbivores that eat macroalgae [2]. Thanks to his research, we now have a better understanding ofthe mechanisms that lead to reef degradation. Whether we choose to invest in the continued research andconservation efforts that could reverse these phase shifts in the face of continued climate change andincreasing human population density remains to be seen.

References1. Interview with John F. Bruno, Ph.D. 02/14/11.2. J. Bruno, et al. Marine Ecology Progress Series. 2010, 413, 201-216.

Figure 3. The dominance of hard and soft corals in a healthy reef is ensured in part by algae-eating organisms such as certain kinds of fish.

Figure 4. A macroalgae-dominated reef.

Source: http://disc.sci.gsfc.nasa.gov/oceancolor/additional/science-focus/ocean-color/bad_ bloom.shtml

Source: http://disc.sci.gsfc.nasa.gov/oceancolor/additional/science-focus/ocean-color/bad_bloom.shtml

Kelsey Ellis is a soph-omore Environmental Science major.

Carolina Scientific


Synthetic organs seem to be the next big idea in medicine. But researchers are beginning to realize they might be able to make something

smaller: synthetic cells. For example, machine-made red blood cells could be the answer to prob-lems ranging from blood shortages to chemother-apy drug delivery. This new technology is nearing reality thanks to the research of Timothy Merkel, a Chemistry graduate student in Dr. Joseph DeSim-one’s laboratory [1]. Previous advances in this field have yielded particles similar to red blood cells, but ones that are quickly removed by the small blood vessels in the lungs [2]. Merkel improved synthet-ic blood cell technology by creating red blood cell mimics (RBCMs), porous and flexible particles that behave like red blood cells and have significantly longer lifetimes than their predecessors (Figure 2). Although synthetic blood could be important in supplying blood to trauma or surgery patients, it also has the potential to improve drug delivery, ear-ly cancer detection, and cholesterol treatments [1]. Currently, chemotherapy drugs are given in as high a dose as the liver can tolerate. RBCMs are able to change their shape in order to squeeze through

small spaces and then spring back to their original form, largely avoiding the liver. This gives them the potential to carry more chemotherapeutic agents to cancerous sites without damaging the liver. RBCMs could also detect biomarkers in the blood that indi-cate the presence of cancerous cells. The next gener-ation of these porous particles is designed to capture DNA and RNA normally destroyed by nucleases, allowing medical researchers to comb the nucleic acids for biomarkers that may point to cancer at an earlier stage than traditional detection methods. Similarly, RBCMs could absorb cholesterol be-cause of their porosity and remove it from the body when the particles are filtered out by the spleen. It all started with PRINT (Figure 1), a technol-ogy developed by DeSimone’s lab that can produce nanoparticles with control over their size, shape, and chemistry [3]. To make PRINT particles, a hy-drogel (a gel-like substance that swells in water) is poured into a mold, solidified by shining light on it, and allowed to swell by hydration [1]. Merkel de-scribed the mold as a “nanoscale ice cube tray” with wells of any size and shape. Using this technique, they were able to make PRINT particles with the

Figure 1. The PRINT technique [1].

Kristen Rosano, Staff Writer

A Synthetic Substitute Delivers More than Blood

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same size, shape, and flexibility as red blood cells, calling them RBCMs. The similar morphology of RBCMs to red blood cells allows them to squeeze through tiny pores and stay in the circulatory sys-tem thirty times longer than the original synthetic cells, which are stiffer [3]. As Merkel explained, “this study was a big step towards making a plastic particle behave like a red blood cell, which could be essential to making a blood substitute happen” [1]. In vitro and in vivo tests of the particles’ abili-ties revealed the extent of their similarity to their natural cousins [2]. The RBCMs were able to squeeze through a channel narrower than their usual width and then relax back to their original shape. The RBCMs were also injected into mice to observe how they travel through the vasculature of a mouse’s ear. The particles appear to leave the bloodstream and enter tissues in a predictable man-ner over time. Although these cell mimics cannot yet transport oxygen, they are very close to hav-ing applications in a wide range of medical fields. RBCMs already seem to be good candidates for

treating splenic disorders because of their tenden-cy to congregate in the spleen, but future research could illuminate how these drug-carrying particles could be directed toward other organs. Organ-spe-cific targeting would im-prove medical treatments by eliminating the adverse effects of these drugs on the rest of the body. Fu-ture research studies will also investigate how the RBCMs could be made to selectively soak up cho-lesterol in order to remove it from the system. And if the particles could be made to carry oxygen, they could be used as a blood substitute, a potentially groundbreaking advance in the world of medicine.

References1. Interview with Timothy J. Merkel, 2/11/11.2. T. Merkel, et al. PNAS. 2011, 108, 586-591.3. Synthetic blood: research pushes nanomedicine forward. 2011, <http://www.unc.edu/spotlight/synthetic_blood>.

Figure 2. Picture of RBCMs taken by fluorescent microscope [1].

Kristen Rosano is a freshman Biology major.

Image credit: www.unc.edu.

Carolina Scientific


Lindsay Ross, Staff Writer

Farmers have a mission to feed the world. To have successful harvests, they need to maximize the productivity of their crop plants. One feature

of plants that growers would benefit from controlling is the shedding of fruit, seeds, flowers and leaves. This shedding process, called abscission, is a natural part of a plant’s life cycle, and the ability to either prevent or induce shedding could boost crop yield [2]. Research by biologist Sarah Liljegren and her lab team is focused on understanding the molecular basis of abscission events. Abscission, or organ separation, happens through the transport and secretion of certain enzymes into the extracellular space. These enzymes alter the sur-rounding cell walls and dissolve the middle lamel-

la—the ‘glue’ that holds plant cells together [2]. The Liljegren lab studies these processes in Arabidopsis plants because they are small, easy to maintain, and can go from seed to seed in only six weeks. For these reasons, Arabidopsis is a common model for plant research. According to Dr. Liljegren, “it is important in the development of Arabidopsis, and other plants, that abscission occurs at the right time, is restricted to specific regions, and that protective scar tissue develops after abscission occurs [3].” Plants are expected to have a large suite of mol-ecules which control, direct, and enact the various

steps involved in the process. Recently, the Liljegren lab has identified two molecules that control abscission produced by the NEVERSHED and EVERSHED genes [1,2]. They uncovered NEVERSHED using a mutant screen in which many wild-type, or, normal Arabidop-sis plants, were exposed to a mutagen (something known to cause changes and defects in DNA). In the offspring of these plants, Dr. Liljegren and her team looked for plants with abnormal abscis-sion, and found a set of plants in which abscission never occurred [3]. Dr. Liljegren then located the DNA mutations in these mutants and found them to be within a single gene, which was named NEV-ERSHED [2]. Next, her lab used microscopy to

investigate the processes occurring in the cells of these mutants [3]. They discovered that the shape of the Golgi apparatus, part of the cell responsible for packing molecules to secrete, was changed (see Figure 1). In addition, the trans-Golgi network, an independent packing station in the cell, was miss-ing in NEVERSHED mutants. The prediction is that molecules needed for abscission are not transported or secreted in Arabidopsis plants with NEVER-SHED mutations [2]. To locate other genes involved in organ shedding, the Liljegren lab conducted another mutant screen

Figure 1. Mutations in EVERSHED restore the independent identities of the Golgi (g) and trans-Golgi network (t) in NEVERSHED mutant flowers.

Plant Organ Donation Shedding For a Good Cause

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using the mutant nevershed plants as the starting point. They looked for offspring of these mutants that had regained abscission [3]. In these new double mutants, the Liljegren lab found a mutation in a gene they termed EVERSHED. These plants have a normal Golgi apparatus and an independent trans-Golgi network (Figure 1). Their investigations suggest that EVERSHED is involved in regulating the timing and region of abscission [1]. The product of the EVERSHED gene is a receptor-like kinase, which is a type of molecule known to bind and modulate the activity of transmembrane receptors in plants [3]. EVERSHED may bind the HAESA and HAESA-LIKE2 receptors (which are required to activate abscission [5]) and pull them back into the cell, thus preventing them from receiving signals which would otherwise begin the shedding process (Figure 2). In the nevershed evershed double mu-tant, it seems the signals to shed may be turned on early and stay on longer. Although evershed mutants look the same as wild-type plants, they have found that other kinases such as SERK1 also affect the timing and spatial definition of abscission [6]. Recently, the Liljegren lab has uncovered an-other gene, CAST AWAY, that inhibits the shed-ding process. They are currently characterizing the binding of CAST AWAY, EVERSHED and SERK1 to HAESA, and looking at the broader functions of NEVERSHED in regulating the movement of

molecules during plant development. In conjunction with labs in Missouri, Norway, Wisconsin, England, and Florida, Dr. Liljegren and her lab are working towards a more complete understanding of organ shedding [3]. They are hopeful that the implica-tions of their research will be broad-reaching—from understanding the complex mechanisms that control the activity of plant receptors to the development of more sophisticated farming techniques.

References1. M.E. Leslie, et al. Development. 2010, 137, 467-476. 2 S.J. Liljegren, et al. Development. 2009, 136, 1909-1918. 3 Interview with Sarah J Liljegren, PhD. 2/11/20114 C. Viotti, et al. Plant Cell. 2010, 22, 1344-1357. 5 S.K. Cho et al. PNAS. 2008, 105, 15629-15634.6 M.W. Lewis, et al. Plant Journal. 2010, 62, 817-828.

Figure 2. EVERSHED may inhibit organ shedding by removing the HAESA and HAESA-LIKE2 receptors from the cell surface.

Lindsay Ross is a junior Biology and Political Science double major and Chemistry minor.

Carolina Scientific


On April 20, 2010, the Deepwater Horizon drilling rig exploded, pouring an estimated four to five million barrels of oil into the Gulf

of Mexico, until it was capped nearly three months

later. This spill has become infamous as one of the biggest man-made natural disasters in history [1]. The media coverage of the spill focused mostly on the negative impact it had on the coastal systems—news networks interviewed angry fishermen and showed clips of shorebirds with their feathers drenched in slimy oil. What was largely ignored, though, is the drastic effect that the spill has had on the microbial populations that live in deep, open water. Since the spill first occurred, Dr. Andreas Teske’s marine sci-ence lab has been working busily to investigate what is happening in the world of organisms that are too small to see, but are too important to ignore. What is especially interesting about the Gulf spill is the presence of plumes, which are concen-trations of tiny oil aggregates that are found deep in the water column of the ocean. The plumes were likely formed when chemical dispersants were spread on the oil slick on the surface of the ocean,

causing it to bead together and sink. There is argu-ment about whether or not the use of dispersants has been a true “mitigation” technique, or, if by trapping the oil under the waves, it has instead managed to sweep the problem under the rug [2]. It is here in the plumes that microbes have become key players in the questions surrounding the oil spill. Various members of Teske’s lab have gone on five research cruises, which have been part of a joint effort involving several universities. The earli-est of these cruises left on May 5, 2010, almost im-mediately after the spill began, and graduate student Luke McKay was one of those on board. He helped to gather as much data as possible and collected samples with whatever was available. Buckets were thrown overboard to gather oil from the surface and plastic bottles were used as containers. The most recent cruise returned in December of 2010, and, unlike the first cruise, had access to state-of-the-art equipment, including a submersible capable of diving to extreme depths, Alvin. Throughout these cruises, hundreds of samples were taken from all three levels of the ocean—the surface, the middle,

Figure 2. A CTD rosette is used to locate plumes and collect water samples.

Figure 1. “Ground Zero,” the site of the Deepwater Horizon explosion.

The Mystery of the Deep: Inside the Plume

Maggie Hunter, Staff Writer

Photo courtesy of Kelly Speare.


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and the sediment on the seafloor. A piece of sophis-ticated equipment called a CTD-rosette looked for low oxygen levels and the presence of hydrocarbons (which is what oil is largely composed of) to locate a plume. Samples taken from inside a plume, when compared to samples taken at any point outside of a plume, have shown that the oil has caused substan-

tial changes in the microbe community [3]. RNA analyses of the sampled microbes indicated that within the plume, there was a signifi-cant decrease in diversity of species. In addition, the microbes that were found in the plume were at a greater density than normal, meaning there were more of them. Over 90% of this enriched population was from a single taxon, Oceanospirialles, a group of organisms which feeds on hydrocarbons [4]. These are naturally occurring microbes, and their response to the oil spill is offering an interesting chance to study hydrocarbon-degrading bacteria. By looking at what processes they use to break down the oil, what chemical products come from these processes, and how quickly theses processes occur, these microbes can provide information as to how they could possibly be used to clean up future oil spills [3]. Despite their capacity to do some good, there is a negative side to this shift in microbial population dynamics. A plume is huge, such as the one studied in September that was 20 nautical miles wide, and such skewed density and diversity

over such large area has the potential to drastically change ocean ecology. Microbes form the very base of the oceanic food chain; if the balance of popula-tion numbers of different species changes drastical-ly, then the entire ecological structure can be altered adversely. It is unclear yet whether the microbe community changes have affected the upper trophic levels much, but it could be because not enough time has passed for noticeable differences to occur. In fact, it seems very unlikely that the food web will not change; the real questions are how much it will change, and whether or not the changes will be cata-strophic [3]. The good news is that, generally, there is more than one “stable state” for an ecosystem, so there is the chance that the system will normalize and remain intact. What this future “normal” might be, though, remains a mystery [2].

References1. Cleveland, Cutler. Deepwater Horizon oil spill. Encyclope-dia of Earth. 2010, <http://www.eoearth.org/article/Deepwa-ter_Horizon_oil_spill?topic=50364>.2. “Black and Blue: Beneath the Oil Spill Disaster.” Produced by the University of Georgia.<http://www.youtube.com/watch?v=xJA7Ax-aUXY>.3. Interview with Luke McKay and Tingting Yang, 2/10/114. T.C. Hazen, et al. Science Magazine. 2010, 330, 204-208.

Figure 3. Undergraduate Kelly Speare filters microbes from a sample of plume water.

Maggie Hunter is a sophomore Biol-ogy and English double major.


Carolina Scientific


Nabila Sarki, Staff Writer

Imagine a world where antibiotics no longer effectively treat infection. Each year in the United States, 90,000 deaths are a result of antibiotic

resistance in the body, increasing from 13,000 in 1992 [1]. Dr. Scott Singleton from UNC’s Eshelman School of Pharmacy is working to find a way to halt antibiotic resistance. Inspired by his interest

in health care, Dr. Singleton is trying to make drug-resistant bacteria incapable of defending themselves against pharmaceuticals that are already on the market [2]. In the past 13 years there have only been 10 antibiotics approved by the Federal Drug Administration (FDA) [1]. The lack of new drugs suggests that a new approach to attacking these bacteria is needed.

When an antibiotic is ingested, the infectious bac-teria becomes damaged and stressed. Antibiotics do not immediately kill the targeted bacteria, but instead cause it to go into a state of mutation that may pre-vent bacteria cell death. DNA alterations can occur, causing a stress-provoked form of DNA repair. The bacteria ultimately become genetically changed, in-creasing their likelihood to survive and pass the new mutated genes to their daughter cells [2]. As this pro-cess continues, the bacterial cells develop genetic changes that could cause a prescribed antibiotic to no longer work, leading to drug resistance. An im-portant factor in the development of drug resistance in bacteria is the enzyme RecombinationA (RecA) (Figure 1). Dr. Singleton described RecA as a “SOS enzyme,” allowing the bacteria to overcome the kill-ing properties of the antibiotic [2]. This enzyme ac-tivates the stress response of the bacterial cell, and repairs the stressed cell through adaptive evolution.

Without RecA, cells are no longer able to mutate. If bacteria were to lose its ability to mutate, it would become impossible for them to fight the damaging effects of antibiotics. Dr. Singleton’s research strat-egy is to stop RecA from allowing bacteria to alter DNA. RecA is inhibited by adenosine diphosphate (ADP) and other related molecules [2], which was used to test resistance of RecA to Escherichia coli (E. coli)(Figure 2). In order to better understand RecA, Dr. Singleton first built a small molecule to interact with the enzyme. The molecule N6-(1-naphthyl)-ADP was

Figure 1. A crystal structure of the protein RecA in com-plex with DNA.

Antibiotics Making a Comeback

By Emw2012 (PDB structure 3cmt, generated in PyMol) [CC-BY-SA-3.0 (www.creativecommons.org/licenses/by-sa/3.0), via Wikimedia Commons

Dr. Scott Singleton, UNC Eshelman School of Pharmacy

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utilized as a competitive inhibitor of RecA. In this experiment, the lab used the principles of negative design to stop RecA from producing non-productive DNA strands when it came in contact with non-tar-geted enzymes. They found that N6-(1-naphthyl)-ADP has the ability to stop RecA from binding to DNA and making certain filaments. These filaments are active in altering the cell’s DNA [3] and could potentially cause the bacterial cell to become resis-tant to an antibiotic. Dr. Singleton’s research could prevent bacteria from becoming resistant. Ideally, traditional anti-biotics in conjunction with new treatments could eliminate resistance before it becomes a problem. Ultimately, researchers hope to stop antibiotics from becoming part of the past. In the future further steps will be taken in order to fully prevent bacterial resis-tance.

References1. Wigle, T. et al. The RecA Protein: An Antimicrobial Target for the Suppression of Growth and Drug Resistance. Poster.2. Interview with Scott F. Singleton, Ph.D. 2/10/11.3. Lee, A. et al. Journal of Medicinal Chemistry, 2005, 48, 5408–5411.

Figure 2. A cluster of E.coli growing together.Credit: Photo by Eric Erbe, digital colorization by Christopher Pooley, both of USDA, ARS, EMU.

Nabila Sarki is a freshman Biology major.

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Patrick Fox, Staff Writer

In order to protect any ecosystem, it is necessary to understand how its organisms interact with their own kind as well as other

species. A frequent problem with examining such relationships is that researchers have simply focused on negative examples (where certain species hinder the prevalence of others) such as predation, competition, and parasitism. A project carried out by five researchers, including UNC Biology professor John Bruno, suggests that positive interactions such as mutualism, commensalism, and cascade effects should be considered in the preservation and restoration of aquatic communities. The facilitation of positive interactions is not new to restoration and conservation efforts, as the prop-agation of nurse plants and foundation species has been utilized in the past. For example, culms of grass

were planted in clusters in marshes to promote shad-ing and aeration of the oxygen-deficient soil [1]. Still, these were minor factors of larger projects, and posi-tive interactions remain underestimated and greatly unexamined by today’s coastal, marine, and aquatic biologists. Different types of positive interactions need to be considered and examined in order to be successfully applied to aquatic ecosystems. The presence of one species can greatly influence the entire ecosystem and allow many other species to inhabit it. For instance, herbivorous animals such as Diadema urchins (Fig-ure 1) and scarid fishes, which graze on invasive al-gae, allow coral reefs to exist by keeping algae popu-lations small in order to preserve oxygen for other organisms [2]. Cascading effects are also instrumen-tal to the well-being of a community. In coastal New

England environ-ments, cordgrass (Figure 2) stabilizes substrates to allow ribbed mussels to inhabit the ecosys-tem, which in turn provide a solid sub-strate for the attach-ment of barnacles, periwinkle snails, and other inverta-brates [3]. Positive inter-actions such as the aforementioned are vital to the liveli-hood of any eco-system, but ecolo-gists need to keep the larger picture in sight. Migrations and the transporta-Figure 1. Diadema urchins, shown here, limit algae growth, preserving the available oxygen

for other organisms.

Thinking Positively About Restoration and Conservation in Aquatic Communities

Source: http://www.marine.usf.edu/reefslab/images/reefcake_presentation/diadema.jpg

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tion of resources cross the boundaries of many eco-systems and inevitably link ones that are thousands of miles apart. Salmon may spend most of their lives in the ocean, but they play a major part in the river ecosystems where they are born, mate, and die. As predators, pink salmon (Figure 3) are needed in the North Pacific to control plankton populations and biomass [4]. At the same time, the salmon also carry essential nutrients from the ocean to the freshwa-ter and forest ecosystems of the Pacific Northwest, where they themselves provide a key source of pro-tein as prey for bears, eagles, otters, and other ani-mals [5]. It must be noted that distinguishing “positive” and “negative” interactions can be difficult because they all have an effect on one another, and a method employed by ecologists today could very well lead to negative consequences in the near future. Furthermore, what works well for the conservation of one ecosystem may not do so for another. Therefore, it is important for scientists to experiment their approaches before actually applying them to the field. Positive interactions need to be more thoroughly examined by ecologists. All organism interactions with one other have an effect on the state of their habitat. By focusing solely on the negative interactions, scientists are discarding about half of the relationships that take place in nature. We have

a significantly better chance of rescuing our coastal and aquatic environments if we investigate and understand every aspect of their existence.

References1. B.S. Halpern, et al. Front Econ. Environ.2007, 5, 153-160.2. P.J. Edmunds, et al. Proc. Nat. Acad. Sci. 2001, 98, 5067-71.3. A.H. Altieri, et al.Am. Nat. 2007, 169, 195-206.4. A. Shiomoto, et al. Mar. Ecol.Progr. 1997, 150, 75-85.5. National Park Service. Anadromous Fish. 2009,<http://www.nps.gov/olym/naturescience/anadromous-fish.htm>.

Figure 2. Cordgrass, common in New England, is es-sential for the survival of many invertebrates.

Figure 3. Pink salmon create positive interactions as both predators and prey.

Patrick Fox is a senior History major.

Source:http://www.nwcb.wa.gov/weed_info/Images/weedphotos/Cordgrass-Smooth---Infest-03-07.jpgSource: http://www.nps.gov/olym/naturescience/pink-salmon.htm

Carolina Scientific


Have you ever wondered why some people can eat anything and never gain weight while others have to struggle with intense diets to

achieve the same results? The answer is rooted in variation: differences in genetics and how certain types of food affect the body greatly contribute to this disparity in results. These deviations may explain why diet and exercise, the two most common interventions for obesity, fail so often. Dr. Martin Kohlmeier, a UNC professor, is interested in applying this knowledge on a practical level: incorporating a person’s genetic information into diet recommendations to create meal plans that account for the uniqueness of the individual. This research, while in its early stages, can prove to be incredibly influential, not just in preventative care but for helping ‘at risk’ populations better manage their health. The main limitation of the traditional diet and exercise model is the assumption that everybody in the same age and gender group has the same needs. People are typically told that eating the recommend-

ed amounts of fats, pro-teins, carbohydrates and essential nutrients, along with physical exercise, will lead to weight loss or weight maintenance. However, the type of food a person consumes is just as important as the amount. A study done to test the effect different types of dietary proteins have on cal-cium metabolism found that vegetable proteins were better absorbed by the body than animal proteins [3]. Such information matters because it shows that different foods, even in the same catego-ry, can vary in effectiveness and should be selected accordingly. Dr. Kohlmeier’s research focuses on understand-ing the difference genetics makes in maintaining a balanced diet. By determining a person’s genetic fingerprint, easily done by taking a blood sample, and using bioinformatics, he has devised a meal plan system that works best for the individual. His program, meant for the general consumer audience, uses thousands of customizable meals that are rated from poor to excellent. It is comparable to a website like MyPlate with an important difference: it ac-counts for your genetic identity and bring intakes of all major nutrients in lines with the user’s personal needs. In a way, Dr. Kohlmeier is bridging the gap between the individual and community; making in-dividualized attention possible on a large scale [1]. Dr. Kohlmeier specializes in nutrigenetic research because he believes that genetics play a key role in the effectiveness of a person’s diet. He has compiled genetic studies for his meal plan program with one

Dr. Martin Kohlmeier, UNC Gillings School of Public Health.

Kristine Chambers, Staff Writer

Cutting Carbs Just Won’t Cut it:Investigating the influence of genetics on metabolic function

Figure 1. An artist’s rendition of the ApoA2 protein.

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of the most prominent discoveries being the effect of ApoA2 -265C on weight gain. ApoA2 -265 is a common variant of an apolipoprotein A-II (Figure 1) that bind with lipids and other proteins to form lipoproteins. Interestingly, individuals who car-ried this genetic variant and ate a slightly higher saturated fat intake (equivalent to 2 pats of butter) were much more likely to gain weight than people with the same exact diet, but had the most common variant of apolipoprotein A-II [1]. If a participant in Dr. Kohlmeier’s study has the ApoA2 -265 vari-ant, however, they would never be able to find out, because this information remains masked. In other words, “all you ever see is a meal plan” and con-sumers will be free to get their nutrition in balance without worrying about the stigma of being geneti-cally abnormal [1]. Making nutritionally sound choices requires much more than just eating your fruits and veggies. Sixty percent of a person’s health can be attributed to genetics or lifestyle patterns, yet there is a short-

age in studies that link the two. Dr. Kohlmeier is a pioneer in his field, and his developing research can contribute greatly in bridging the gap between genetics and nutrition.

References1. Interview with Martin Kohlmeier 2/11/20102. R, Mackintosh et al. Obesity: A research journal. 2001, 9, 462-469.3. Breslau, N et al. Journal of Clinical Endocrinology and Metabolism. 2011, 66, 140-146.4. Poort, SR et al. Journal of the American Society of Hema-tology. 1996, 88, 3698-3703.

Figure 3. A sample meal from Dr. Kohlmeier’s system complete with nutrients and the option to ex-plore other combinations.

Kristine Chambers is a freshman Nutrition major.

Image Credit: Martin Kohlmeier

Carolina Scientific


Connie Wang, Staff Writer

After enjoying a beer on a hot summer after-noon, even some of the more intoxicated students have probably noticed that not long

after being out in the sun, their beer has developed an absolutely foul odor. This phenomenon is often referred to as ‘skunking’ and was noted by research-ers as far back as 1875. It was UNC’s own chemistry professor, Dr. Malcolm Forbes, who elucidated the chemical mechanisms by which beer skunking oc-curs. One of the major components of beer, as well as a key player in its skunking process, is a herbaceous plant called hops (Figure 4). Hops are used in the brewing process and contribute to the distinct beer flavor; beers that are stronger in hops content usu-ally have a stronger aroma. The organic compounds derived from hops, isohumulones, are what give beer its bitter taste. Isohumulones are, however, incredibly susceptible to photodegredation. When ultraviolet or visible light strikes isohumulones,

it facilitates a reaction catalyzed by another compound found in beer, called riboflavin. The free radical intermediate pro-duced by the light induced reaction is then converted to 3-methylbut-2-ene-1-thiol (Figure 2), causing the foul, skunky odor [1]. Surprisingly, this ‘skunky thiol’ is not what is found in skunk secretions but is actually identical to that which is found in feline urine. Forbes was able to elucidate the mechanism of this reaction using time-resolved electron paramag-netic resonance (TREPR) spectroscopy, a powerful technique used to study and identify transient free radical complexes. A strong magnetic field is ap-

Figure 1. (Left) Brown and green bottles shield the passages of photons and slw down the skunk-ing process.

Dr. Malcolm Forbes, Chemistry professor at UNC.

Figure 3. (Right) Co-rona encourages its consumers to drink its product with a lime, which reduces the inten-sity of the odor caused by skunking by masking it with the flavor of the lime.

The Secret to Skunking

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plied, followed by an analysis of signals resulting from magnetic moments of electrons [1]. It is because of ‘skunking’ that most beer is sold in tinted brown or green bottles that shield the passage of photons and slow down the skunking process. A va-riety of newer methods have been developed to combat the problem of skunking. Corona, for example, uses a marketing strategy in which it encourages its consumers to drink its product with a lime (Figure 3). The lime reduces the intensity of the odor by mask-ing it with the flavor of the lime. Chemically modified hops prod-ucts have also been synthesized. These hops extracts are still susceptible to photodegradation, but do not undergo the same reaction to produce the skunky thiol, and thus fail to develop the odor when exposed to light. Of course, all of these alternatives come at the cost of the beer’s flavor. Forbes’ research has been key to the beer industry, fueling the search for a way to prevent this skunking phenomenon while retain-ing the original hops flavor. So next time you pick up a beer, be sure to remember the carefully calcu-lated conditions, down to the color of the bottle, that were made to keep your beer from smelling like cat urine.

References1. M.D. Forbes. Chemistry. 2001, 21, 4553-61.

Figure 4. (Left) Humulus lupulus, a common species of hops.

Figure 2. (Below) Reaction of isohumulones catalyzed by riboflavin to produce 3-methylbut-2-ene-1-thiol.

Connie Wang is a junior Biology major.

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Kati Moore, Staff Writer

A major issue often brought up in science classrooms, political debates, and environmental news reports is global

warming and the resultant environmental changes. But what effect do these environmental changes have on organisms around the globe? Many scientists are still trying to answer this question. Biologist Dr. Lauren Buckley wants to take this question a step further. She explores not only how climate changes, but also how an organism’s own biology affects its population distribution. Buckley seeks to answer the more complicated question, “How does biology (morphology, physiology, and life history) determine an organism’s response to environmental change?

[1]” Temperature is an important factor for an organism’s survival in a particular area. This is especially true for ectotherms, whose activity levels depend directly on temperature. Butterflies, for instance, bask in the sun in order to warm up enough to fly. All of the butterfly’s activities are constrained by flying—finding food, finding mates, and lay-ing eggs [2]. The amount of time they can fly is

directly related to the number of eggs they can lay. Because of this, knowing the heat tolerances of butterflies can predict their population dynamics. As the average temperature in a butterfly’s habitat increases, the butterfly population may or may not be able to adapt to stay in that location, depending on its thermal tolerances and ability to shift those thermal tolerances.

The Arctic and Antarctic are often cited as being strongly affected by climate change because they are experiencing a greater temperature increase than other areas of the world. But the animals in the tropics may be in more danger, says Buckley. This is because creatures at the poles are already adapted to deal with large seasonal temperature fluctuations, unlike creatures near the equator, where temperatures are fairly constant year-round. As a result, organisms at the poles have larger thermal tolerances than those in the tropics. This means they can survive in a greater range of temperatures, and will be less affected by a greater temperature increase. A common method of predicting where organisms can live is the use of correlative models, which combine location data for different species with environmental variables for those locations. Using these models, scientists can determine the outer limits of environmental conditions that a species could inhabit. These outer limits are referred to as a “climate envelope.” When accounting for climate change, the correlative model assumes that the species will follow the climate envelope as it moves geographically [2].

Dr. Lauren Buckley, As-sistant Professor at UNC, is currently studying the biogeography of climate change.

Figure 2. The top topographical map of Colorado shows the current distribution of C. meadii butter-flies. The middle and bottom maps show the distribution after a 3-degree Celsius increase in tem-perature, with and without adaptation, respectively, as pre-dicted by Buckley’s mechanistic model.

The Greater Meaning of Global Warming

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A major problem with the correlative model, says Buckley, is that it does not take into account many biological factors, such as thermal tolerances, and whether these thermal tolerances will evolve with climate change. To take these factors into account, Buckley uses what are called “mechanistic” or “process-based” models, which describe biological constraints on whether an organism can live in a given area. These models give researchers a better overall picture of a species’ population distribution and allow them to more accurately predict how climate change will affect organisms. An example of this can be seen with the population distribution predicted by Buckley’s mechanistic model for C. meadii butterflies in Colorado (Figure 2). Though mechanistic models give a better prediction for species distribution with respect to climate change, they must be tested against as much data as possible. Buckley and her coworkers, in their work with butterflies, for example, gather data from fieldwork (see Figure 3) and from museums that hold information about butterfly traits and how these traits have changed over time. It is important to gather such data because traits such as wing coloring can affect the body temperatures of an organism – the more black markings on butterfly wings, the higher the rate of heat absorption, which then translates to shorter basking time and the ability to fly sooner. The need for this type of data is a main reason Buckley studies the butterflies in Colorado – that is where the most information has been recorded over time about the butterfly populations. One challenge to predicting how climate change will affect different species is that each species will respond to temperature changes differently. The question, Buckley says, is how to come up with models for predicting population change that can represent enough species and still be accurate. Researchers have to rely principally on case studies – in-depth studies of just a few organisms – from

which to build models. These can then, hopefully, be translated to the bigger picture of how climate change will affect organisms across the world. This kind of data would be useful for policy makers who have to decide where to place the cap, if possible, on temperature increase. For students interested in how climate change affects population distribution of different species, the undergraduate concentration in Global Environmental Change may be a promising option, says Buckley.

References1. Buckley, Lauren. 2011. Buckley Lab – Biogeography of Climate Change. <http:// http://www.unc.edu/~lbuckley/lab/pmwiki.php>.2. Interview with Lauren Buckley. 2/11/11.

Figure 3. Fieldwork includes capturing butterflies and observing them in other habitats.

Kati Moore is a freshman Biology major.

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Jana Lembke, Staff Writer

If you’ve ever tried to hide a strong emotion, such as anger or euphoria, you’ve probably noticed that unconscious and unavoidable

physical reactions inevitably reveal your true feelings to others. These types of bodily responses to different emotional states are exactly what interest Dr. Barbara Fredrickson, Bethany Kok, and other researchers at UNC Psychology’s Positive Emotion and Psychophysiology Lab (PEPLab). As the name suggests, part of what the lab studies is how positive emotions influence people’s physiology. Likewise, the team examines how initial physiological factors might affect how, or if, people will experience a certain emotion in response to different situations [1]. “From both of these perspectives, we’re bridging the artificial mind-body division,” Kok explains. “As this research proceeds, we’re seeing more and more

that psychological and physiological processes aren’t separate, but part of the same system [1].” The interconnected and reciprocal nature of physi-cal and psychological processes served as the basis for Kok and Fredrickson’s latest empirical study, which focuses on vagal tone as a product and pre-dictor of positive emotions and social connectedness. The vagus nerve, or cranial nerve X, extends from the medulla, down the neck, and into the abdomen, where it innervates the internal organs and sends sensory information back to the brain. Because acti-vation of the vagus typically leads to a reduction in heart rate and blood pressure, it is often used as an index of parasympathetic nervous system activity, or the body’s functioning during a state of rest [1]. Va-gal tone (VT) refers to this activity and is calculated by analyzing heart rate variability, or how in sync the heart and respiration are. Most importantly, VT serves as a physiological marker of autonomic flex-ibility and adaptability; that is, the capacity of the parasympathetic nervous system to adapt to changes in circumstance by modifying emotional arousal, respiration, heart rate, and attention [2,3]. Assuming that the enhanced self-regulation asso-ciated with high VT will help people capitalize on socioemotional opportunities as they arise, Kok and Fredrickson hypothesized that the autonomic flex-ibility indexed by VT would lead to increased social connectedness and positive emotions over time [2].

Figure 1. Upward trend of vagal tone and social con-nectedness

Figure 2. Positive feed-back of vagal

tone and psychosocial well-being

Mind-Body Interdependencies “Positively” Influence Well-Being

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These resulting opportunistic gains, in turn, were expected to lead to elevated VT. Because high VT is associated with greater self-control and emotion regulation, closer friendships, superior cognitive flexibility, and feeling more secure in one’s relation-ships, the expected results lay the groundwork for a positive feedback cycle toward greater autonomic flexibility and psychosocial well-being. To test their hypothesis, the researchers measured the VTs of 73 community-dwelling adults at the be-ginning and end of a 9-week period during which the participants monitored and reported their positive emotions, and the degree to which they felt social-ly connected each day. As expected, VT and well-being reciprocally predicted one another [2]. Adults who possessed higher initial levels of VT increased in social connectedness and positive emotions more rapidly than others. Additionally, participants who reported increased connectedness and positive emo-tions showed increased VT, independent of their ini-tial levels. “We’ve shown that a physiological variable, vagal tone, can influence the effectiveness of a psychologi-cal intervention—a body-mind link,” says Kok. “In addition, our work is one of the first studies to show that psychological change, increasing well-being,

can result in a positive change in vagal tone. This is notable because, until recently, the vast majority of psychophysiological research focused on stress and negative outcomes of psychological stress [1].” The results of Kok and Fredrickson’s study pave the way for more discoveries to be made about the mechanisms governing the VT-emotion relationship. “The vagus is just a cranial nerve, albeit a very influential one, but how do you get from the activity of a nerve to having deeper friendships?” Kok asks. “How do you go from ‘I feel socially connected,’ to ‘my vagal tone is higher’? That’s fascinating to me [1].” In her continued research, Kok is going beyond self-reports to investigate how individuals with high vagal tone act in social situations. Identifying be-haviors or skills characteristic of people high in VT might help us understand how social connections are created, and has applications from autism therapies to interventions aimed at decreasing loneliness and social isolation [1]. The demonstrated links between human thriving and VT illustrate the potential for positive social and emotional experiences to have physiological impacts that foster an upward spiral of personal well-being.

References1. Email with Bethany Kok. 2/5/102. Kok, B. E., and Fredrickson, B. L. (2010). Biological Psy-chology. 85, 432-436. 2010.3. Powerpoint Presentation by Bethany Kok, 2/5/10.

Figure 3. Anatomical location of the vagus nerve, in yellow

Jana Lembke is a junior Psychology major.

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Matt Dutra, Staff Writer

The future of nanotechnology may lie no farther away than your desk drawer. Most current technology is silicon-based –

computer chips, motherboard circuitry, you name it – it probably relies on silicon. While this hasn’t been a problem thus far, silicon-based technology will reach its highest potential within around 10 years, maybe as soon as 2015[1], due to its limits on heat dissipation – a problem central in developing better and better nanotechnologies. With these dates looming ever nearer, materials scientists have been searching for plausible alternatives to silicon. Now, back to your desk drawer. Hopefully, if you open it, you’ll find a pencil or two. As all good col-lege students know, pencil lead isn’t actu-ally lead at all – it’s graphite. If you were to apply a layer of Scotch Tape to a piece of graphite and fold and unfold the sticky sides, you would find that graphite is com-posed of layers. Each individual monolayer – a hexagonal network of carbon atoms (Fig-ure 2) – is known by the name of graphene, and it is this compound that’s caught the at-tention of many ma-terials scientists and

physicists alike, including UNC’s own Dr. Dmitri Khveshchenko. While many scientists are racing to their labs to fold and unfold layers and layers of Scotch Tape in the hopes of finding graphene, Dr. Khveshchenko instead prefers to take a more math-ematical approach to describing what makes this carbon lattice so interesting. Physically speaking, graphene has incredible potential as a semi-conductor. In any semi-conduc-tive material, there exist two energy bands of inter-

est – a lower energy valence band, in which ground state valence electrons lie, and a higher energy conduc-tion band, in which there are no ground state electrons. Sepa-rating the two bands is a band gap, a sort of void where electrons can never reside. When electrons in the valence band absorb energy, they can be excited into the conduction band, which allows them more freedom to move about. It is this capabil-ity of charged particles to move within the con-duction band, known as charge-carrier mobility (or more simply, car-rier mobility) that dis-tinguishes good semi-conductive materials from bad ones Graphene, surprising-ly enough, has extraor-

The Physicist’s Playground

Figure 1. The Dirac points in graphene are points at which the otherwise separated valence band (green-yellow) and conduction band (red-blue) touch.

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dinary carrier mobility. According to Dr. Khvesh-chenko, this is because the valence and conduction bands in graphene actually touch in six points, known as Dirac points (Figure 1)[1]. Furthermore, gaps can be induced in these points [2] through the application of an external magnetic field, which, if controlled, would allow graphene to function in con-ventional transistors – central parts of things such as computers, radios, electric parts of automobiles, etc. However, the Dirac points in graphene are of inter-est to Dr. Khveshchenko for a second reason – the movement of electrons near them can be described mathematically by the relativistic Dirac equation.

While this may seem underwhelming to those of us who aren’t theoretical physicists, Dr. Khveshchenko de-scribes the phenom-enon as a “physicist’s playground”, capable of “demonstrating phe-nomena…..such as Klein’s Paradox (re-flectionless tunneling through potential bar-riers), atomic collapse (unstable electronic orbits in the presence of charged impuri-

ties), Zitterbewegung (oscillations of the center of a propagating electronic wave packet), and Schwinger’s particle-antiparticle pair creation in an electric field” [3]. Graphene has great potential as a semi-conduc-tor due to its charge-carrier mobility and ability to better dissipate heat, can be used to study atomic phenomena in quantum physics, and can be found in objects as commonplace as your pencils. It also has been considered as a replacement for silicon in many microtechnologies, including central com-ponents such as transistors – electronic devices present in things such as computers, cell phones, and radios, to name a few. Not bad for a substance that can be isolated with nothing more than deter-mination and a roll of Scotch Tape.Figure 2. The molecular structure of graphene is a single

layer of a hexagonal carbon lattice.

References1. Interview with Dr. Dmitri Khveshchenko, 2/7/112. Khveshchenko, D.V., Coulomb-interacting Dirac fermions in disordered graphene. Physical Review B, 2006.3. Emails with Dr. Dmitri Khveshchenko, 2/16/11

Dr. Dmitri Khveshchenko, physics professor at UNC.

Matt Dutra is a junior Chemistry major.

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Madison Roche, Staff Writer

When playing telephone with your friends, it’s obvious that all it takes is a little misunderstanding to miss the whole point

of the beginning sentence. A similar phenomenon occurs when animals try to signal different messages to their friends. Professor Haven Wiley is currently studying signal detection theory, which is leading to some strong predictions about the evolution of signals and responses in animals. For further explanation, think about the analogy of the game of telephone. Just like in the game of telephone, often times there are background noises and distractions which cause weak communication. Most importantly, however, the game involves being

able to detect the words that are being said and the ability to retain and relay this information to the next player. Therefore, there are two main components to both the game of telephone and animal communica-tion; detectability and the receiver’s responsiveness. A lot of things get lost in the shuffle during com-munication, whether it is the sound being drowned out or the receiver not responding. Studies of animal communication have found that whenever there is a change in the probability of detecting the back-ground stimulation, there is a corresponding change in the probability of a correct detection (Figure 1). This has proved to be a fundamental implication for the evolution of communication and is where the

Figure 1. In the presence of noise, receiver’s receptors do not completely separate noise and nignal from noise alone. The receiver’s threshold sets the probabilities s of the four possible outcomes; (1) CD- Correct detection (signal, response), (2) MD- missed detection, (3) FA- false alarm (response but no signal), (4) CR- correct rejection (no signal, no response). This graph displays that the two kinds of errors are not independent and receivers cannot simultaneously minimize MD and FA.

The Game of Telephone and an Analysis of Signal Detection in Animals

Graphic Credit: Dr. Haven Wiley

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signal detection theory comes in. According to Professor Wiley, the signal detec-tion theory provides a solution to this problem and other weaknesses of weak communication. After extensive research, experiments, and calculations Professor Wiley has formed a complex conclusion. First of all, the signal detection theory leads to a pre-diction that receivers evolve to optimize the net util-ity of their responses. Based on the theory of natural selection, the fit animal can survive and reproduce to make the optimum offspring. Receivers that can adapt and evolve to optimize their receiving against the distractions will have the optimum receiving signals, increasing their fitness. In turn, signalers should then evolve with a bal-ance between increased detectability of signals, in-creased complexity of encoding and restriction of signals to intended receivers. This means that sig-naler’s predators are likely to increase their ability to intercept messages not intended for them. This is similar to when a group of gossip-hungry girls eavesdrop to hear other people’s secrets. The group of girls developed an increased sense of hearing, so if others do not want the gossip girls to hear them, there is a need to further code their conversation with their friends to avoid interception. Professor Wiley has broken down why signal re-

search theory provides great promise for the future studies of the evolution of animal communication. The theory suggests new ways to design experi-ments in order to include all of the restrictions put on a good communication line. He claims that with this approach, we can learn more about an animal’s adaptations for situations with a lot of background noise, the ability to detect and discriminate signals, and the evolution of increased detection and receiv-ing abilities [1]. In other words, how to create a flawless game of telephone.

References1. R. H. Wiley. Advances in the Study of Behavior. 2006, 36, 1-31.

Figure 2. Professor Richard Haven Wiley.

Madison Roche is a sophomore Biology ma-jor with a Chemistry and Spanish double minor.

Image Credit: http://www.cee.unc.edu/faculty.cfm.

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Since the days of Stonehenge, astronomy has evolved from observing solstices and align-ments to capturing star explosions in the distant

universe; from stones and pyramids on the ground to robotic telescopes on the highest mountain tops of the world. In the age of modern astronomy, you don’t need to physically journey to distant mountain tops. With an iPhone or a Blackberry you can, with a click of a button, submit an observation to a galaxy far, far away from virtually anywhere via the Internet. This is exactly the kind of thing UNC Professor Dan Reichart and his research team have been cre-ating and perfecting—the Skynet Robotic Telescope Network. Using Skynet, a tap of the keyboard can open a clam shell telescope dome 7400 km away—and yes, it is named after the artificial intelligence system that controlled robots in The Terminator.

The web interface started in 2005, governing the six primary PROMPT telescopes that were built to rapidly capture the afterglows of gamma-ray bursts, or GRBs—highly energetic explosions of stars occur-ring billions of light years away. Since then, Skynet has expanded its reign of robotic telescopes world-wide, and has made astronomy more practical and fea-sible. The numbers aren’t bad: 30,000 North Carolina grade school students, 12 undergrad institutions, and 20,000 members of the general public using the sys-tem for their own astronomy projects, cutting-edge re-search published in more than a dozen journals, and a whopping total of 3.2 million images taken so far [1]. Scientists use the ’scopes for a variety of astro-physical research, from chasing asteroids to taking pretty pictures for NASA’s Astronomy Picture of the Day. The UNC team mostly focuses on cosmol-

Apurva Oza, Staff Writer

Astronomical Kingdom

Figure 1. The six PROMPT robotic telescopes in Cerro Tololo, Chile.

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ogy—the study of the universe’s beginning and how it evolves. During a gamma-ray burst, two jets of ra-diation and energy are released. If we are lucky the axis of the jet aligns with Earth and we are hit with a measurable but not dangerous surge of gamma rays. The distant blasts of gamma rays are detected by a satellite called SWIFT orbiting the Earth. The message is then relayed to robotic telescopes like PROMPT, and the race begins. The scopes must immediately slew (astronomy jargon for rotating a telescope) and start exposing or else the vital data will be gone forev-er. One can imagine doing this science a few decades ago, before Skynet: stumbling out of bed into the ob-servatory (granted you live there), messing with the controls in your sleep, only to find out that you missed it—you were too late. Once the team gets good data, they quickly perform photometry on the burst—mea-suring its brightness over time—and get their results out to the GRB community via “GRBlog,” where GRB scientists report their preliminary findings. “Waiting for the world to turn around can be a real nuisance when catching GRBs,” says Dr. Reichart. So in addition to the 13 telescopes scat-tered around the globe in North Carolina, Virginia, Colorado, Thailand, and Italy, the research team has received a grant to build 4 more PROMPT tele-scopes at Siding Springs Observatory, Australia. “…the sun will never rise,” jokes graduate student Justin Moore, pointing out the fact that due to the longi-tude of Australia in relation to Chile, astronomers won’t lose time waiting for the Earth to turn around when a GRB goes off—there will always be a ’scope handy.

Soon the network will also be observing the uni-verse at radio wavelengths, capturing phenomena we can’t normally detect in visible light. A 20-me-ter radio telescope in Green Bank, West Virginia, is also an addition to Skynet. The team often goes on expeditions to new observing sites. If a university has an old telescope sitting around that isn’t used much, it can be automated, remotely-controlled and used nightly by anyone. Take the 24-inch telescope in the dome at the Morehead Planetarium, for exam-ple. Historic and monumental as it may be, it spent most of its time sleeping under the Carolina Blue sky. “I’m going to put this old guy to use,” says Josh Hais-lip as he finishes the final touches on installing conduc-tor rails on the dome with Justin Moore. “Soon More-head guest night could be every night from a laptop.” Another goal the UNC team has is to trans-form the Skynet interface so that is more us-er-friendly. They envision a place where peo-ple can exchange ideas, data, images, and interact—a kind of networking site for researchers. Despite the convenience and accessibility of re-mote observing, many people would still prefer to do astronomy at the observation site itself, and feel that thrill. I think every astronomer should make the journey to an observatory at least once to see where the images are coming from. My first jour-ney was at the Pic du Midi Observatory, lodged at 2877 m on top of the Pyrenees mountains. Look-ing out across the snow-glazed mountains, I felt like I was looking across the pride lands in the movie The Lion King: “…everything the light touches is our Kingdom.” In our Astronomical Kingdom, it is every photon we collect in the sky that is ours. When we can govern the sky with an army of robotic telescopes equipped and ready to fire at our command, cosmic events will have a tough-er time disappearing before we can catch them. And it is only once we catch them that the uni-verse’s most puzzling questions will be answered.

References1. Interview with Dr. Daniel E. Reichart. 2/10/2011.2. Thorsett, S.E. Astrophysical Journal Letters 1995, 444, L533. Melott, A.L. et al. . International Journal of Astrobiology 2004, 3, 55–61.4. Petit. P et al. Astronomy and Astrophysics, 2010, 523.

Apurva Oza is a junior Physics major.

Figure 2. One of the PROMPT telescopes shown in an open dome.

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“Satisfaction of one’s curiosity is one of the

greatest sources of happiness in life.”

- Linus Pauling

Carolina Scientific Spring 2011Thanks to Stephen Farmer and Donald Hornstein for funding and support.

Front Cover: Coral Reef, Credit: Richard Ling, www.rling.comTable of Contents: Nanowire Array, Microspace 4, Credits: Z.L. Wang, Georgia Tech

and Dr. Zhengwei Pan, Dr. Zhanjun Gu, and Dr. Feng Liu, University of Georgia

This publication was funded at least in part by Student Fees which were appropriated and dispersed by the Student Government at UNC-Chapel Hill.

Spring 2011 Issue

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Transcript of Spring 2011 Issue