Category: Students Page 35 of 42

Turtle Sexes are Temperamental

On February 3, 2014

In Animals, Biology, Climate/Global Change, Guest Post, Students

Guest post by Lauren Burianek, doctoral candidate in cell biology

A pair of one-week-old red-eared sliders. The one on the right looks a little cranky. (Tadpole667 via Wikimedia Commons)

A pair of one-week-old red-eared sliders. (Tadpole667 via Wikimedia Commons)

When humans are developing, they snuggle in a warm environment and everything is provided by the mother. The sex of this developing fetus is determined by its individual genetic makeup, particularly the presence of the X and Y chromosomes.

But laid as an egg in a hole on a riverbank, the sex of a red-eared slider turtle is determined by the temperature at which the egg is developed.

At temperatures above 84.6°F, the hatchling will develop into a female, but at lower temperatures, the hatchling will develop into a male. However, at exactly this temperature (called the pivotal temperature), half of the hatchlings will be female and the other half will be male.

Scientists have no idea how temperature affects the sex of the turtle hatchlings, but researchers in Blanche Capel’s lab at Duke are trying to find out.

Red-eared sliders breed in late spring near riverbanks in Louisiana. Researchers carefully collect the eggs from common nesting spots and send the eggs to Duke University. In the Capel lab, graduate student Mike Czerwinski then buries the eggs in sand and places them into incubators at different temperatures. From here, he will analyze the gonads, or sexual organs, of the turtle embryos incubated at the different temperatures.

Grad student Mike Czerwinski in the Capel lab.

Czerwinski and his colleague Lindsey Mork discovered that when the turtle embryos were incubated at the pivotal temperature, both gonads developed into either testes or ovaries, but rarely did the two gonads develop into one of each.

Then, they incubated the turtle embryos at the pivotal temperature, dissected the two gonads and incubated each of them at different temperatures, either male-developing or female-developing temperatures. Surprisingly, the separated pairs of gonads still attempted to develop into the same sex regardless of the incubation temperature.

Tyrannosaurus Rex may have had temperature-sensitive eggs too. (tlcoles via Wikimedia Commons)

For example, if one of the gonads incubated in the male-developing temperature readily turned into a testis, the other gonad of the embryo, even though it was incubated in female-developing temperatures, is slower to develop into an ovary than expected, suggesting that it was genetically predisposed to be a testis.

“The results are exciting because it shows that there is a global mechanism beyond temperature dependence that allows for sex determination,” said Czerwinski. “All we’ve known up until now is that temperature is important for these turtles, but now we know that there also has to be a genetic component. Sex determination is so varied between different species, but this might give us insight into how we’re all connected.”

Climate change could definitely be a factor in the survival of these turtles and other temperature-dependent species. After all, the dinosaurs are thought to have exhibited temperature-dependent sex determination.

With increasing temperatures, a higher proportion of hatchlings will be females. Snapping turtles, however, have found a way to combat this – by moving north. The same species of snapping turtles exhibit different pivotal temperatures at different latitudes.

Evolution truly is an amazing process.

Stem Cells Might Tell Us Why Chimps Can't Blush

By Karl Bates

On January 28, 2014

In Animals, Biology, Genetics/Genomics, Guest Post, Students

Guest post by graduate student Sheena Faherty

Clint the chimpanzee was the first member of Pan troglodytes to have his DNA sequenced. Thanks, dude. (Photo from Yerkes National Primate Research Center.)

Clint the chimpanzee is at it again.

The first chimpanzee to have his genome sequenced in 2005 has now made another mammoth contribution to science, this time with his stem cells.

Using these stem cells, Greg Wray, professor in Biology and Evolutionary Anthropology and his former Ph.D. student, Lisa Pfefferle, recently published an article detailing an exciting new genomic tool that provides a sneak peek into how fundamental differences at the genetic level can lead to drastic differences we see at the outward level between humans and chimpanzees.

This fascinating new approach is based on a specific type of adult stem cells, known as adipose derived stromal cells (ASC). The beauty of ASCs is that they can be manipulated to morph into different types of mature cells. These cells can then be poked, prodded, and scrutinized under the microscope as a means to delve into fundamental questions regarding the molecular basis of human origins.

This work adds a powerful new tool to the field of comparative primate genomics. The goal is to discover the source of traits that set humans apart from other animals, like spoken language or the sole ability to blush when embarrassed.

By comparing humans with our closest genetic cousin, the chimpanzee, we can begin to uncover qualities unique to both humans and chimpanzees. These discoveries might lie within the genome.

Lisa Pfefferle developed a new technique, based on Clint’s stem cells, to get at human-chimp differences. (Photo courtesy of Lisa Pfefferle.)

In a beautifully designed experiment, Wray and Pfefferle obtained a precious stock of Clint’s frozen ASCs, manipulated them into fat cells, known as adipocytes, and then compared his adipocytes with three different populations of human ASCs. (Clint, a resident of the Yerkes National Primate Research Center in Georgia, died at age 24 a few months before his genome was published.)

Using next-generation sequencing approaches, the researchers were then able to compare over 10,000 genes between human and chimpanzee. The results of this comparison show central differences within the set of genes that may be contributing to the obvious dissimilarities between humans and chimpanzees.

For example, genes controlling the development and function of the immune system were significantly higher in chimpanzees than in humans. It is well documented that chimpanzees are able to heal wounds faster than humans. This may be why.

In contrast, genes involved in the cell cycle and DNA processing, important for passing on genetic information and repairing DNA damage within cells, were expressed at a higher level in humans.

This novel approach of using ASCs in a controlled laboratory setting will undoubtedly be a valuable complement to existing studies on comparative primate genomics.

CITATION: Pfefferle, LW and Wray GA. Insights From a Chimpanzee Adipose Stromal Cell Population: Opportunities for Adult Stem Cells to Expand Primate Functional Genomics. October 2013: 1–18, doi:10.1093/gbe/evt148

Why Meteorites Are So Hard to Find in North Carolina

By Erin Weeks

On January 24, 2014

In Faculty, Field Research, Physics, Science Communication & Education, Students

by Erin Weeks

Note: This is the first in a multi-part series following Nick Gessler’s course on meteorites and the history of the solar system. Astronomy enthusiasts should check out the North Carolina Museum of History’s Astronomy Days happening this weekend, Saturday, January 25.

Visitors to Nick Gessler’s lab can touch the moon — literally — and a whole lot of meteorites (Photo: Eric Ferreri)

A meteorite hasn’t been discovered in North Carolina in over 80 years, but Professor Nick Gessler dreams that his students will be the first to break that streak.

On the first day of his class at Duke, Gessler hauled in three tables worth of meteorites, chunks of rock and metal that hurdled through outer space for millions, even billions of years before surviving the descent into Earth’s atmosphere. Among his collection are pieces broken off from the moon, Mars and the dramatic Chelyabinsk meteorite that lit up Russia and YouTube in February 2013.

“That’s what they look like,” Gessler said, gesturing toward one table. “They’re ugly rocks.”

That’s not entirely fair. Past their melted, black crusts, most of the meteorites glint with flecks of iron. Some thin slices, when finely polished and held up to a light source, resemble stained glass. But ugly or no, the rocks have captivated human interest since people first observed them falling from the sky. Now, they’ve attracted Duke students in wide-ranging fields, from English and history to mathematics and engineering, united by a common interest in the extraterrestrial.

Gessler has a couple of theories about why North Carolina has seen a dearth of meteorite discoveries. First, farming practices have changed — farmers found many meteorites while tilling their land and dislodging the stony debris. These days, farmers rely on heavy machinery unfazed by rocks.

Second, Gessler thinks it’s possible that, despite our astronomical advances, light pollution may have clouded our chances of seeing minor meteors falling to earth.

“Maybe people just don’t look up at the sky like they used to,” he said.

Throughout this course, it seems certain his students will be looking up. Each has been assigned a North Carolina meteorite to research — they’ll ferret out old newspaper clippings and find when and where it fell, whether the land is private and what the likelihood of finding remnants now might be. Gessler will instruct them on the art and science of meteorite hunting, and eventually the students may put their skills to work in the field.

And who knows — some of them might even find the meteorites beautiful.

New Course Offers Lessons from Lasering Priceless Art

By Erin Weeks

On January 20, 2014

In Chemistry, Computers/Technology, Faculty, News Release, Students, Visualization

Duke graduate student Tana Villafana and chief conservator at the NC Museum of Art William Brown stand over The Crucifixion (inset). (Photo: Martin Fischer)

By Erin Weeks

A group of chemists at Duke University has gained recognition in recent years for shooting lasers at medieval artwork — technology that allows a harmless peek at the many layers and materials in a painting and offers insight into long gone eras and artists. Now, Duke students will have the chance to learn from this pioneering work at the intersection of chemistry and art history in a new course on the science of color.

The course coincides with the publication of the first scientific measurements from the laser work, reported Jan. 20 in the Proceedings of the National Academy of Sciences.

“The images we have now are enormously better than a year ago,” said Warren S. Warren, head of the lab performing the imaging and the James B. Duke professor of chemistry. He and fellow Duke authors, grad student Tana Villafana and associate research professor Martin Fischer, have not only demonstrated the technology works — they’ve shown it works at an incredible level of detail, telling the difference, for example, between nearly identical pigments.

But lasering The Crucifixion by Puccio Cappano was just the start, as the team envisions countless more cultural applications of the technology. Given enough funding and manpower, they could visualize ancient scrolls of text too fragile to unroll, reveal the bright colors that once adorned Greek statues, learn the secrets of China’s terracotta warriors, and even detect the beginnings of pigment degradation in aging artwork.

There are talented people in art conservation, Warren said, whose work could benefit from more advanced technology, and there are talented people at the cutting-edge of laser science looking for meaningful ways to apply their inventions. For the past several years, Warren’s lab has brought these people together.

Now, he hopes to accomplish something similar with students at Duke. Warren, Fischer, and another chemistry instructor, Adele DeCruz, are teaming up to teach “The Molecular, Physical, and Artistic Bases of Color” in the second half of spring semester.

The class will visit the Nasher Museum of Art, the North Carolina Museum of Art in Raleigh, and possibly even the National Gallery of Art in Washington, D.C, to learn first-hand from art conservators and working artists. Students can expect to learn about how humans have used and made pigments over the millennia; how color works at a molecular level; and the basics of how human vision, microscopes, cameras, and lasers all see or image color.

Students can register for the half course, CHM 590, until the add/drop deadline for classes on January 22. “Students should not be scared off by the course number,” Warren said. “The prerequisite is one college-level science course, and the intent is to make both the science and artistic components accessible to a broad audience.”

Funding for the research was provided by National Science Foundation grant CHE-1309017.

CITATION: “Femtosecond pump-probe microscopy generates virtual cross-sections in historic artwork.” Tana E. Villafana, William P. Brown, et al. Proceedings of the National Academy of Sciences, Jan. 20, 2014. Doi: 10.1071/pnas.1317230111

New Blogger: Olivia Zhu

By Olivia Zhu

On January 15, 2014

In Neuroscience, Physics, Science Communication & Education, Students

Hi! My name is Olivia Zhu, and I am a sophomore biophysics major hailing from Pleasanton, California. I’m thrilled to start writing for the Duke Research Blog.

When I started my Duke career, I had absolutely no idea what research was. I had a vague conception of it as a drawn-out, painstaking process in which one traded in his life’s freedom for a micropipette. However, midway through my freshman year, a conversation with Professor Henry Greenside prompted me to reconsider. Professor Greenside inverted my perspective on research: he showed me that research did not revolve around tedious procedures, but rather around the pursuit of answers to fascinating questions. Since then, all sorts of research topics, particularly those with some aspect of physics, have captivated me. I found that research fulfills the idealistic conception I have always held of education: research represents the ultimate pursuit of pure knowledge, often without the pressures of immediate practical application.

Currently, I work in the Mooney Lab of neurobiology, which studies the learning processes in songbirds. Via surgical viral infection, I am examining the role that dopamine plays in this circuit.

In other matters, I enjoy forsaking my science-based identity by taking English, art, and history classes. I play soccer, run around campus, read classic novels, and discuss philosophy with friends. At Duke, I am a part of the Round Table and pWILD communities. Sometimes I miss hiking in California or exploring the islands in Beaufort, North Carolina, but I know there’s no place I’d rather be than here in Durham.

I’m looking forward to sharing my exploration of research at Duke!

Keely Glass, the Omni-Chemist

By Karl Bates

On January 13, 2014

In Cancer, Chemistry, Guest Post, Physics, Students

Guest post by Addie Jackson, North Carolina School of Science and Mathematics

Keely’s picture from Linked-In

Ask Keely Glass how she would describe her research to a third grader, and she laughs while thinking of the best way to explain.

“So, say you’re sitting next to your friends. One has really black hair and one has red hair. They have different hair colors, because their hair colors come from the different pigments. Your friend with black hair has more eumelanin, while your friend with red hair has pheomelanin.”

A PhD candidate in the chemistry department at Duke, Glass currently does research on analytical methods to analyze these pigments in biological and historical samples. She’s also using those skills to provide direct chemical evidence for the presence and preservation of eumelanin in the fossil record.

Trust us, that’s a fossil squid. (Courtesy of Willsquish on Wikimedia Commons.)

Glass elaborates by describing a common fascination with squids, also known as cephalopods, who release pure black eumelanin when faced with a predator. Two kinds of melanin are present in nature: eumelanin (brown to black in color) and pheomelanin (yellow to red). Through her work, she and her team have verified that eumelanin is preserved in the fossil record, and showed that it can be identified directly using its known chemical signature. They have also found that the eumelanin identified in the fossil record is not significantly different from the modern eumelanin, meaning it hasn’t evolved in the more than 160 million years since.

Another lab at Duke, run by Professor Warren S. Warren, uses a pump-probe microscopy system to characterize melanins to attempt to find statistically significant variations between melanomas (skin cancers) that do not develop metastases. The hope for this project is to improve diagnostic accuracy for these metastatic melanomas, through analyzing the melanin distribution in “old” archived (stored for >10 years) tissue samples. Glass says, “The paper I wrote with them essentially says if melanin resists degradation (stays intact and doesn’t alter) over more than 160 million years, it’s fairly clear that it will resist degradation in storage for 10 years. In other words, it’s pretty clear that these archived tissue samples are still viable for melanin analysis.”

Fourteen months in the life of one man’s nodular melanoma. (Courtesy of 0x6adb015 via Wikimedia Commons.)

Working with the Warren group, Glass also found that the pump-probe system was sensitive to the higher iron-concentration fossilized squid melanin as compared with modern cephalopod melanin. They were able to mirror the iron-independent signal by adding iron to modern cephalopod melanin. This proved to be interesting because metastatic melanomas have increased iron levels, which may or may not be responsible for signature variations.

The classical fields of chemistry (analytical, organic, physical, theoretical, inorganic, and biological) have become more integrated over time, making the labels themselves increasingly obsolete. To better label themselves, most chemists mix and match: “I’ve called myself at various times a ‘Bioanalytical Chemist,’ ‘Biophysical Organic Chemist,’ ‘Analytical Biochemist,’ ‘Organic Geochemist’ etc. to emphasize that the systems I’ve worked on, the techniques I’ve used, and the skills I’ve obtained are diverse and dependent on the project I’m defining.”

Glass says, “When I think that the names have gone a little haywire, I jokingly call myself an omni-chemist. Like most chemists I work on diverse array of projects that require techniques and knowledge from many fields.”

Addie Jackson interviewed Keely Glass and wrote this post as part of a Science Communication seminar led by NCSSM Dean of Science Amy Sheck.

Passion, Determination Drive Liu's Research Forward

By Karl Bates

On January 10, 2014

In Animals, Behavior/Psychology, Biology, Guest Post, Science Communication & Education, Students

Guest post by Madeleine Gonzalez, NC School of Science and Math

Long before she was a scientist, Irene Liu was an animal lover, cutting coupons for food for the cats and dogs that she wished she had, admiring birds, and even subscribing to the famous Ranger Rick magazine. Naturally her interest would stem from this passion, leading to her exciting career in evolutionary biology.

Irene Liu gently handling a captured bird during some fieldwork in a mangrove swamp. (Photo courtesy of Irene Liu)

Today she uses birds to answer questions that are applicable across different systems and organisms. At the University of Maryland, she began with questions like, “Do birds have dialects?” and today, as a graduate student at Duke University, she investigates the extra-pair mating habits of blackbirds.

“We know that birds are famous for infidelity,” she says. ” Within one breeding season you can see mom and dad and baby birds. They look like they are one family, but actually mom and dad are off mating with other individuals and will then raise together these chicks in this nest,” she describes. Irene Liu works to understand the benefits of infidelity in bird populations, exploring how patterns vary on frequency.

Between the fieldwork, the lab work, and the occasional, tedious computational work, Irene Liu has had some extraordinary experiences.

Working around the people with similar drive and interests, she has thrived as a young scientist.

She loves her field work. “Getting out to these isolated places that most people don’t get to see is a real privilege, and seeing nature just happening as if I am not even there.” She plays a fun game of catching and outsmarting the birds as she collects samples and records her observations, which may not always be particularly easy. In fact, certain obstacles have been particularly devastating.

One time while returning from the Bahamas, her summer collections were seized and incinerated at the airport after failing to comply with US regulations and not being informed of the necessary permits beforehand. However, she returned in the following year to collect an even better sample, thoroughly learning a lesson the hard way.

A redwing blackbird that fell into Irene’s clutches sports his new ankle band.

“I have become the obsessive person that will call the government agencies and check,” she says. It has made her the permit expert within the department and inspired a seminar.

For other young or aspiring scientists, Liu advises, “Pick something that makes you want to get out of bed every morning, but being happy does not mean denying that there are going to be challenges and obstacles in the way.”

Even though an event such as her experience in the Bahamas can be utterly discouraging and disappointing, it is the passion that will drive the progress and ambition. It is important to remember that there is a time to worry about the future and there is a time to work, Liu said. The future is overwhelming sometimes with a given task at hand, but it’s important to not lose perspective. Even for basic research, sometimes people demand tangible immediate benefits, but that is not guaranteed.

“Our solutions to the world’s greatest problems will surely come from the most unexpected places. You don’t have linear consequences,” Liu said.

Mady Gonzales interviewed Irene Liu and wrote this post as part of a Science Communication seminar led by NCSSM Dean of Science Amy Sheck.

Schmitt Blends Locomotion and Arthritis

By Karl Bates

On January 10, 2014

In Animals, Biomedical Engineering, Guest Post, Lemurs, Science Communication & Education, Students

Guest post by Joseph Kirollos, NC School of Science and Math

Walking up to the Trent Semans Center at Duke University to interview Dr. Daniel O. Schmitt, professor of Evolutionary Anthropology and teacher of anatomy at Duke University, I couldn’t help but wonder why he would pursue seemingly unrelated interests. On one hand, he studies the locomotion and evolution of primates while at the same time, he but he also has a strong clinical interest in both human functional anatomy and osteoarthritis.

Dan Schmitt with his wife, Christine Wall, who is also an evolutionary anthropologist at Duke. (Duke Chronicle photo)

How did these interests come about? Which came first? These were the questions that ran through my head as I read through his papers and prepared for the interview. Though as Dr. Schmitt sat down and began to tell his story, it didn’t take long for all of my doubts and confusions to quickly fade away. Everything began to blend, and it all made sense.

As it turns out, Dr. Schmitt was actually a latecomer to clinical research and it was through natural variance and human evolution that science first captivated his interest. Although he was somewhat of a “terrible college student,” he quickly developed a genuine curiosity in the vast physical differences between species. It was later during his graduate studies at SUNY Stony Brook, where he worked with live animals, that he became a post-doc drill associate in anatomy and began to wonder how factors such as leg design, pelvis width, or even high metabolism affected how humans and animals move. By asking these questions, he expanded his interests to the next level and created a stepping stone that would lead him into both his evolutionary and clinical research.

[youtube http://www.youtube.com/watch?v=VA8diXNvffY?rel=0]

At the locomotion lab at Duke University, where he continues to research today, he was able to delve headfirst into Evolutionary Anthropology as he studied the selecting factors that govern limb design, gait mechanisms, and energy efficiency of locomotion in primates and humans. One of his main interests even today is the origin of human’s unique design and bipedal locomotion.

Schmitt, who teaches anatomy to medical students, went to the Duke-NUS graduate medical school in Singapore in 2012 to talk about medical education with colleagues. (Duke-NUS)

In fact, the first of his papers that caught my attention dealt with this very topic. It was a paper refuting the commonly accepted theory that humans evolved from terrestrial knuckle-walking primates such as gorillas and chimpanzees rather than tree-climbing ancestors (see the paper here). As I discussed the paper with Dr. Schmitt, he revealed that he normally preferred to avoid controversy, yet, in this case, he felt that he couldn’t “buy into” the fact that humans would evolve from terrestrial knuckle-walking ancestors. He said, “I couldn’t think of one good reason for them to stand up.” Interestingly, the paper analyzes features from the human wrist that previously supported knuckle-walking ancestors and turns it around and says that in fact these features actually may support that we had tree-climbing ancestors. However, in person, Dr. Schmitt referred to this argument as being rather “nihilistic” as it challenges an idea but doesn’t really propose an alternative.

Of course, it was only a matter of time before these interests in both human anatomy and the evolution of biomechanics in primates naturally brought him to wonder how human joints have so uniquely and efficiently adapted. Working with Dr. Ershela Sims, he has studied osteoarthritis in humans, a debilitating and widespread disease of the joints, and today he still explores the factors that cause it.

I found this quite interesting as my family has a long history with severe osteoarthritis. Interestingly Dr. Schmitt said that it was not intervention and treatment that he cared about, but rather he was interested in the basic science, the deeper causes that lead to osteoarthritis. Is there more than just obesity and wear and tear that leads to osteoarthritis and how does it affect human movement? These were the questions that he would ask. Naturally this blended quite well with his gait studies with primates as osteoarthritis affects the gait mechanisms and energy efficiency of humans. So by the time our discussion had finished, I felt a little dumb that I previously felt as though Dr. Schmitt had an unusual range of interests. I realize now that they blend in perfect harmony, each inspiring the other, leading to amazing discoveries.

Joseph Kirollos interviewed Dan Schmitt and wrote this post as part of a Science Communication seminar led by NCSSM Dean of Science Amy Sheck.

Not Your Mama's Chem Lab

By Erin Weeks

On November 21, 2013

In Chemistry, Environment/Sustainability, Students

By Erin Weeks

Deep in the basement of French Family Science Center, eleven chemistry 210 students are completing one of their last labs of the semester. Bob Marley plays from a speaker in the ceiling, and the students are huddled around their computer screens, watching lines plot on a rainbow-colored graph.

It looks like an average lab session—but believe it or not, the students are engaged in cutting-edge energy science.

The students worked with cobaloxomine, shown here, and a variety of colored cobalt complexes in the lab.

The students worked with cobaloxime, shown here, and a variety of colored cobalt complexes in the lab (Courtesy Wikimedia).

While undergraduates can still expect to learn the techniques and concepts familiar to introductory chemistry classes everywhere, Duke’s chemistry department recently revamped the laboratory portion of CHEM 210, Modern Applications of Chemical Principles, with the help of a mini grant from Trinity College of Arts and Sciences. Now students learn through the lens of one of modern chemistry’s biggest challenges: energy.

Associate chair and professor Kathy Franz says the department wanted students to be able to tie their laboratory work to real-world chemistry problems—like converting sunlight into usable fuel.

“Researchers around the world are working on each step needed to close the loop of artificial photosynthesis and link it to fuel cell use,” the lab manual reads. “There are still basic chemical questions yet to be answered about that deceptively simple-looking equation” that describes photosynthesis.

Some of those top researchers, including Dan Nocera and his lab at Harvard, use cobalt-based catalysts in their efforts to streamline artificial photosynthesis—and now, so do chemistry students at Duke. The lab today tasks students with building their very own simple cobalt catalysts to perform half of the artificial photosynthesis equation.

Just like professional chemists, the students face technical frustrations and rewards. Lab manager Deborah McCarthy rushes around the room with a sharp eye, correcting missteps. One group forgot to add eosin Y, a reddish dye, to their solution. Another group fails to dissolve their cobalt complex in acetone, and yet another skimped on the NAD+. But on second and third tries, when everything goes right, the students’ rainbow graphs spike perfectly, signaling their success—they’ve produced NADH, a form of stored energy used in living cells.

Post-Doc Named Pew Scholar of the Month

By Karl Bates

On November 14, 2013

In Animals, Biology, Students

Natalia Martin, Ph.D.

Natalia Martin, a post-doctoral researcher in the lab of Alejandro Aballay in Molecular Genetics and Microbiology, has been named the biomedical researcher of the month by the Pew Charitable Trusts.

Martin is examining the role nerve cells play in innate immunity against bacterial infections in the worm Caenorhabditis elegans as a member of Pew’s Latin American fellows program. Pew has provided funding to more than 200 young scientists from Latin America since 1991 to receive postdoctoral training in the United States. Martin’s mentor, Aballay, was a Pew fellow himself in 1998. Both scientists are from Argentina.

C. elegans image by Dan Dickinson, Goldstein lab, UNC Chapel Hill – http://wormcas9hr.weebly.com/

You can see videos of Martin talking about her work in English and in Spanish here: Immunity Studies Cross Scientific and Continental Borders.