Tuesday, April 30, 2013

Imagining Southern bodies: A review of 'Sex, Sickness and Slavery'

Some Southern physicians twisted medical science to aid the proslavery argument, writes historian Peter McCandless in the journal Southern Spaces, a digital initiative of Emory University Libraries.

McCandless' article is a review of "Sex, Sickness and Slavery: Illness in the Antebellum South," by Marli F. Weiner with Mazie Hough. Below is an excerpt:

"A Gullah proverb warns, 'every sick ain't fa tell de doctor' (don't tell the doctor all your ailments). After reading 'Sex, Sickness, and Slavery,' the wisdom of that saying seems more obvious, especially as it applies to women and blacks in the antebellum South. The late Marli Weiner, a professor of history at the University of Maine, demonstrates convincingly how antebellum southern physicians—white males all—used information about their patients to advance their own professional and sectional political agendas. They actively used medical science to justify racial and sexual hierarchies, to define and characterize bodies by sex, race, and place, and to enhance their authority as physicians and white men. In the process, they wrestled with the problem of what Weiner calls 'ambiguous bodies' (mixed race, sexual hybrids, and 'monstrosities') and with the complex relationships between minds and bodies. ...

"They debated what aspects made blacks medically suitable for slavery, but southern physicians accepted the assumption that slavery benefited blacks, and some actively sought to provide medical evidence for it. Southern physicians had no difficulty justifying black subjugation.

"Justifying the domination of women should have been even easier. European and northern academics and physicians had already provided plenty of arguments and evidence. Nevertheless, as 'Sex, Sickness, and Slavery' shows, southern physicians faced a unique problem: How could they reconcile arguments for sexual and racial subordination in a way that did not undermine either? They had to categorize people by both race and gender, and in ways that supported male gender and white racial superiority. Few physicians doubted white or male supremacy, but a coherent racial ideology required that white women be shown to be superior to black men. Moreover, if women were indeed the weaker and sicklier sex, demanding protection and gentle care, how could one justify making black women perform hard physical work alongside black men, even when close to giving birth and shortly after delivering?"

Read the whole review in Southern Spaces.

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The rare book that changed medicine

Tuesday, April 23, 2013

Human mobility data may help curb urban epidemics

By Carol Clark

Residents of cities like New York and London tend to move about in fairly predictable routines, following the same routes between their jobs and schools each day. When it comes to a city in the developing world, however, human movement is much more varied, a finding with important implications for controlling an infectious disease pandemic.

The Public Library of Science (PL0S One) published the first major analysis of daily human mobility in a resource-poor city, led by scientists at Emory University’s Department of Environmental Studies.

The researchers used GPS technology to quantify the movement and contact dynamics of nearly 600 residents of Iquitos, Peru. They applied the data to create a computer simulation for predicting the transmission rate of a flu virus.

“We found that the irregular movement of people in Iquitos increases the probability of flu transmission by 20 percent, compared to cities in developed nations,” says lead author Gonzalo Vazquez-Prokopec, an Emory disease ecologist.

The study authors are making their data estimates and simulation methods publicly available, so that other researchers can conduct further experiments and build on their work.

“It is estimated that more than 90 percent of the mortality from a potential influenza pandemic would occur in developing countries, where vaccine and antiviral stockpiles are minimal,” the study authors write. “The lack of detailed models to estimate infectious disease transmission dynamics in such settings limits the ability to enforce containment measures or plan emergency preparedness strategies.”

Rather than commuting to a single workplace, poorer residents of Iquitos often work several jobs, such as driving a three-wheeled mototaxi, or selling produce at multiple markets. Photo via Wikipedia Commons.

Most previous data on human mobility, drawn from cities in North America and Europe, shows that urbanites visit an average of two to four locations daily.

In Iquitos, human movement is much more fluid.

Full-time jobs are scarce for the population of 400,000 living along the left bank of the Amazon River, on the edge of the Peruvian rainforest. “Most people are self-employed or have several jobs to try and make ends meet,” Vazquez-Prokopec says. Common occupations of poorer residents include driving makeshift taxis or selling produce at one of the multiple open markets in the city.

Some previous studies in other parts of the world have looked at cell phone data to track and model human movements. The data is limited, however, due to issues of antenna density, restricted information from cell-phone carriers and the fact that some people do not have cell phones.

For the Iquitos study the researchers outfitted 582 residents with an i-GotU GPS device, which is ordinarily used as a photo-tagging tool for hikers. The i-GotU was selected for the study because it is small (about the size of a thumb drive), waterproof, relatively affordable, has a large memory and long battery life, and is password protected.

Each study participant wore one of the devices like a necklace as they went about their daily routines during a two-week period. The devices were programmed to capture location data every 2.5 minutes, from 5 am until midnight.

About 70 percent of the world's 3.3 billion city dwellers live in resource-poor environments. Aerial view of Iquitos by Viault / Wikipedia Commons.

The study yielded more than 2 million raw GPS positions, with an error margin of just four meters, tagged with date and time. The researchers used a data-reduction algorithm to calculate the average number of locations visited each day for the study participants as a whole, and by age groups, ranging from 7 years old to 60.

The results show that the participants visited an average of six locations per day overall. People in the peak working age group of 36 to 45 visited an average of nine locations daily.

“The more random your movements are, the more chances you have to pass a pathogen like the flu,” Vazquez-Prokopec says, explaining the 20 percent higher transmission risk, compared to a developed city.

While the Iquitos study represents just one city in the developing world, the researchers hope that the fine-scale, spatial-temporal data they have gathered will help fill the knowledge gap on human mobility in similar cities.

About 70 percent of the world’s 3.3 billion city dwellers live in resource-poor urban environments. “Uncovering the basic mechanisms governing complex human behaviors in these environments is paramount for developing better infrastructure, fostering economic development and responding to infectious disease threats,” Vazquez-Prokopec says.

The Emory research team also included Uriel Kitron, chair of the department of Environmental Studies, and post-doctoral fellow Donal Bisanzio. The study is part of a larger, ongoing disease ecology project centered in Iquitos that also includes scientists from the University of California, Davis, the U.S. Navy, the University of Iowa, Tulane University, San Diego State and researchers in Peru.

How the dengue virus makes a home in the city
Disease trackers take aim at dengue fever

Monday, April 22, 2013

Turning green slime into liquid gold

What if you could replace the petroleum molecules that we use in fuel and so many other products with a substitute made from algae?

Emory alum Harrison Dillon will explain how he’s doing just that, as the guest speaker for Emory’s Biology Undergraduate Research Symposium, on Thursday, April 25 at 4 pm in WHSCAB Auditorum.

In 2003, Dillon and fellow Emory alum Jonathan Wolfson founded Solazyme, named one of the “50 Hottest Companies in Bio-energy” for 2011 to 2012 by Biofuels Digest.

During a TEDxAtlanta talk (see above video) in 2010, Dillon explained how he and Wolfson became close friends as college freshmen and dreamed of starting a company together. They parted ways for graduate school. Dillon, who loved biotechnology and genetics, was working on a PhD in human genetics, but halfway through he became disenchanted with the idea of a career in the pharmaceutical industry.

“I started reading the scientific literature about micro-organisms that make stuff that’s flammable,” Dillon recalls. “And I thought, if you could use all this genetics and biotechnology to make organisms that make stuff that burns efficiently, maybe you could make renewable fuel. I called Jonathan and I said, ‘I know what our company’s going to be: We’re going to use micro-algae to make fuel.’ And he said, ‘That’s delusional. I love it.’”

Happy Earth Day!

Oil change

Monday, April 15, 2013

A primatologist on the origins of morality

Primatologist Frans de Waal, director of Emory's Living Links Center at the Yerkes National Primate Research Center, spoke with CNN's Kelly Murray about his new book, "The Bonobo and the Atheist: In Search of Humanism Among the Primates."

Below is an excerpt from the interview, posted on CNN's Light Years blog:

CNN’s Kelly Murray: Tell us about the title of your book.

Frans de Waal: Well, the reason I chose that title is, when I bring up the origins of morality, it revolves around God, or comes from religion, and I want to address the issue that I think morality is actually older than religion. So I’m getting into the religion question, and how important is religion for morality. I think it plays a role, but it’s a secondary role. Instead of being the source of morality, religion came later, maybe to fortify morality.

CNN: How would you say that ethics or morality is separate from religion?

De Waal: Well, I think that morality is older. In the sense that I find it very hard to believe that 100,000 or 200,000 years ago, our ancestors did not believe in right and wrong, and did not punish bad behavior, did not care about fairness. Very long ago our ancestors had moral systems. Our current institutions are only a couple of thousand years old, which is really not old in the eyes of a biologist. So I think religion came after morality. Religion may have become a codification of morality, and it may fortify it, but it’s not the origin of it.

Read the whole interview here.

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Thursday, April 11, 2013

The growing buzz on animal self-medication

In addition to gathering pollen, honeybees collect plant saps to create a resinous material that reduces bacteria and parasite loads in hives. (Photo by Louise Docker/Wikipedia.)

By Carol Clark

Birds do it. Bees do it. Even forest-dwelling ants do it. Increasing evidence suggests that a wide range of animals self-medicate.

“We need to pay close attention to how animals may use plants or other materials as medicine, because it has direct implications for human health and food production,” says Emory biologist Jaap de Roode.

De Roode wrote a review of recent studies on self-medication in animals for the current issue of the journal Science. De Roode and his co-authors, Thierry Lefèvre and Mark Hunter, recently published their own study showing that monarch butterflies use toxins found in milkweed to cure themselves and their offspring of disease.

De Roode will also be giving a talk on animal self-medication on Saturday, April 20, as one of 11 speakers set for TEDxEmory.

Milkweed, left, is a pest to farmers, but medication to monarch butterflies. The insects use toxins in some species of the plant to kill parasites in their offspring. (iStockphoto.com)

Until a little more than a decade ago, de Roode notes, primates were among the only animals besides humans thought to have the capacity for self-medication. Chimpanzees, for instance, had been observed in the wild eating plants with anti-parasitic properties but with little or no nutritional value.

Then some birds were found to line their nests with plants that ward off parasites, fungi and other pathogens. Just last year, ecologists in Mexico published a study suggesting that house sparrows and finches may be studding their nests with cigarette butts because nicotine reduces mite infestations.

The evidence for self-medication is actually stronger for insects. It’s easier to conduct laboratory experiments on them, and to clearly demonstrate whether an insect’s preference for a certain food delivers a benefit to fitness and survival.

“It’s now clear that animals do not have to have a big brain or advanced cognitive skills to use medicine found in nature,” de Roode says. “We’re seeing that these behaviors can be innate.”

Emory biologist Todd Schlenke, for instance, recently found that when fruit flies sense parasitic wasps in their vicinity, they lay their eggs in an alcohol-soaked environment, forcing their larvae to consume booze as a drug to combat the deadly wasps. And the larvae themselves, given the choice, prefer to eat food high in alcohol if, and only if, they are infected with the wasp eggs. The alcohol treatment is highly effective, greatly improving the survival rate of infected larvae.

No one has researched the possibility of whether alcohol could have a similar effect on humans suffering from blood-borne parasites.

Fruit flies have evolved the capability to seek out alcohol to combat infections by parasitic wasps. (Photo by Andre Karwath/Wikipedia.)

De Roode notes that insects and other animals may hold many medicinal secrets of potential benefit to humans.

Honey bees, for example, make a sticky substance called propolis from plant resins and incorporate it into the architecture of their hives. This resinous material has been shown to reduce bacteria and parasite loads in hives. A recent study showed that bees exposed to the spores of fungal parasites increase their resin foraging rates, suggesting that making propolis may be a case of self-medication.

In the wild, honey bees line the entire interior of their hives with resin to create what is called the “propolis envelope.” Many commercial beekeepers, however, select for bees that don’t gather resinous material, because the substance gums up the manmade hive frames.

Meanwhile, honeybees in the United States are suffering from die-offs that have wiped out nearly half of the hives needed to pollinate fruits and vegetables in the country. Drought, pesticides, viruses and other pathogens have all been suggested as possible causes of the bee deaths.

Could discouraging a self-medicating trait in bees also be a contributing factor?

“Those are the kinds of questions that are important to look at and think about,” de Roode says.

The monarch butterfly’s medicine kit
Fruit flies use alcohol as a drug to kill parasites
Fruit flies force their young to drink alcohol – for their own good
Tapping traditional remedies to fight modern superbugs 

Wednesday, April 10, 2013

'Jurassic Park' tracks and poop, now in 3-D!

Universal Pictures

By Carol Clark

One of my favorite movie scenes of all time is the one with the cups of water in the 1993 science fiction classic “Jurassic Park.” The kids are trapped in an enclosed Jeep. It’s raining and dark. Then a series of faint, low “booms” grows slowly louder as the water in a pair of plastic cups on the dashboard trembles, signaling the approach of a Tyrannosaurus rex.

While most people fixate on the horror of the giant teeth and powerful jaws of an approaching T-rex, Emory paleontologist Anthony Martin is tickled by the thought of all the lovely, deep tracks the dinosaur is leaving in the mud with each booming thud of its triple-toed feet.

Martin is an ichnologist, specializing in the study of life traces like tracks, tooth marks and scat. He was among the first to rush out and see the recently released 3-D version of “Jurassic Park.”

The 3-D version is a chance for a whole new generation to enjoy the cheesy thrills of Steven Spielberg’s masterful tribute to dinosaurs. And just to make sure viewers get a bit of real science along with their popcorn, Martin has written a post called “The Ichnology of Jurassic Park” for his "Life Traces" blog. It’s a must-read before you make tracks for the theater.

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Dinosaur burrows yield clues to climate change

Tuesday, April 9, 2013

He created the ideal learning climate

By Kimber Williams, Emory Report

It's Thursday up on the fifth floor of Emory's Math and Sciences building, and the familiar scent wafting through the hallways can only mean one thing. Waffles, and lots of them — homemade, golden brown and hot off the griddle.

The man behind the waffle iron is Woody Hickcox — geologist and climatologist, self-taught watercolorist/muralist, and resident chef.

Hickcox next to some of his art.
Hickcox is known both for creating the colorful artwork that blooms throughout the walls of the Department of Environmental Studies, and for his weekly waffle feasts that draw students, staff and faculty.

Hickcox explains how the Waffle Thursday tradition started:

"I was talking to a class about climate change, how water from the Gulf Stream flows to the North Atlantic and sinks. So we were talking about how when you have fluids of different densities, they will sink and rise. As an example, I talked about mixing waffle batter and whipped egg whites – if you put the waffle batter on top of the egg whites, it will basically turn over.

"Well, a lot of students have never seen waffles made from scratch. So I brought in the apparatus to make them. Afterward, one of the students, who's now a physician, said, 'Why don't you do waffles every week.' So we started making waffles every Thursday. We'll make up a big batch of waffle batter, and since I go to Vermont, we have a ready supply of real maple syrup.

"One or two people will often step in to help cook the waffles. You'll usually find a dozen people standing here, talking and eating, and a long line. That's what it's really all about, bringing people together. It creates community."

A senior lecturer in environmental studies, Hickcox is set to retire in May after nearly 29 years of teaching at Emory.

Read the whole interview with Hickcox in Emory Report. 

A geologist paints Darwin

Photos by Emory Photo/Video.

Monday, April 8, 2013

Intersex: A lesson in biology, identity and culture

“It’s fun helping people make connections and think of things in new ways,” says neuroscientist Sara Freeman, who won a Crystal Apple teaching award for her class on intersexuality.

By Carol Clark

As a little girl growing up in Atlanta, Sara Freeman says she was a tomboy, preferring to play in the dirt than with dolls. “I dealt with the psychological issue of not behaving like a feminine ideal,” she recalls, “but I don’t think most people ever feel like a perfect version of their sexual assignment.”

She went on to major in biology at the University of Virginia, where she developed an interest in reproductive endocrinology. Freeman is now on the brink of receiving a PhD in neuroscience from Emory, focused on the evolution of behavior, especially in relation to hormones. Her thesis involves the oxytocin system and the social attachment of mammals, drawing from her work in the lab of behavioral neuroscientist Larry Young.

“I find it fascinating that a chemical like a hormone can have such a big influence on an organism’s social interactions,” says Freeman, who loves teaching as much as research.

Last fall, Freeman taught an undergraduate class that she developed called “Intersex: Biology and Gender.”

The seed for the class was planted in 2010, when Freeman watched a short documentary called “One in 2,000” by Fanlight Productions. The film takes its name from the number of people born in the United States who have a variation in sex characteristics that defies the common biological parameters of male or female. “Intersex” is an umbrella term used to describe the phenomenon.

Click here to watch a documentary called "XXXY" by the Intersex Society of North America.

“One of the most surprising things to me about the movie was learning the prevalence and variety of intersex conditions,” Freeman recalls. “All these different names of different diagnoses floated across the screen, and I only recognized four out of about 25 of them. I thought, ‘This is ridiculous. I’m trained in reproductive biology.’”

In an extreme intersex case, a baby may have such ambiguous genitals that the parents and doctors wonder if the child is a boy or a girl.

Other intersex cases may have no overt features. Someone with complete androgen insensitivity syndrome (CAIS), for instance, may look and feel like a female although she has a male XY chromosome pair instead of the usual female XX. The body of a person with CAIS does not respond to the steroid hormone that stimulates the development of male characteristics, despite functional testes hidden in the abdomen.

A child with Klinefelter’s syndrome also may not exhibit any evidence that he has the standard male XY chromosome pair, plus an extra X chromosome. During puberty, however, he may develop slightly enlarged breasts, or bigger hips than usual for a male.

During the 1950s, some members of the medical community began to “fix” the problem of overt sexual ambiguity in babies by making them appear either fully male or female through surgery or hormonal treatments. Some physicians counseled against telling these children about their birth condition, because it could cause them mental trauma.

“Generations of people who were operated on right after they were born had no idea what happened to them,” Freeman says. “But in recent years, intersex people have started to come out and talk about their experiences.”

Some of them never fully identified with the sex category that had been arbitrarily “assigned” to them. Some also bear scars from repeated surgeries that have reduced their sexual sensation.

A growing movement calls for gender identity to be left up to intersex individuals to decide as they get older. “Today, we have a lot more information and advocacy about intersex,” Freeman says, “but some doctors still have the attitude of, let’s fix it and not talk about it.”

The complexities of intersex issues stuck in Freeman’s mind. Later, she took a course on teaching undergraduate science from Pat Marsteller, director of Emory’s Center for Science Education, and she received a Dean’s Teaching Fellowship, giving her the chance to design a course of her own.

Her resulting class on intersex is geared to upper-level undergraduates and is cross-listed in Biology, Sociology and Women’s, Gender and Sexuality Studies. “The idea was to bridge science and the humanities, so students from both worlds can come together and learn from each other,” Freeman says.

She also drew from the knowledge of Emory graduate students and faculty from both worlds to develop the course. Eight of these specialists served as guest instructors for the class, giving their perspectives from neuroscience, women’s, gender and sexuality studies, psychology and pediatric endocrinology. And a local intersexed individual came and spoke, to give the class a personal perspective.

The class delved into social and scientific history, questions of ethics and the nuances of semantics. For instance, while the medical community refers to intersex conditions as “disorders of sexual development,” many intersexed individuals do not feel like they have a disorder.

The students discussed theories around the ideas of disability and normalcy. What does normal mean? And what constitutes a normal male and a normal female?

“College is a coming-of-age time,” Freeman says. “I want students to evaluate the social pressures they experience on a day-to-day basis as they form their own identities, and to learn not to judge others.”

Click here to play the "Meiosis Game."
To help teach the complex biology underlying human sexuality, Freeman enlisted the help of Matt Gilbert, an instructor at the Art Institute of Atlanta who is also a web developer and graphic designer. Freeman and Gilbert worked together to develop two online, interactive sites that turn biological processes into a game-like format.

The “Meiosis Game” takes a player through the cellular division process that results in sperm and egg cells. By clicking through the long chain of steps of sex chromosomal sorting involved during meiosis, students see how natural variations in that process can result in an embryo with sex chromosomes other than the expected XX or XY.

The “Steroidogenesis Game” shows how steroid hormones, like estrogen and testosterone, are synthesized from cholesterol by enzymes. Players start with a molecule of cholesterol and instructions to create a target hormone. They then click on different available enzymes to see how applying each one changes the structure of the molecule. As they make their way through the enzymatic pathways, players see how the absence of any one enzyme may prohibit them from reaching the end goal of creating a particular hormone.

Click here to play the "Steroidogenesis Game."
The tactile, visual, step-by-step “games” serve as a good introduction to complicated biological concepts, while also helping students review material and prepare for tests.

“It’s fun helping people make connections and think of things in new ways,” Freeman says. “The varieties of body and mind that the human species is capable of are beautiful and something to be celebrated. The concept of what is male and what is female shouldn’t be expected to fit into narrow categories.”

The entire class of Freeman’s first group of students nominated her for Emory’s coveted Crystal Apple award for excellence in teaching. A Crystal Apple category didn’t exist for graduate students, but the awards committee created one for Freeman, due to popular demand.

“It meant a lot to me, to get that kind of recognition from my students,” Freeman says, adding that she also learned a lot. “Delving into the humanities side helped me become more aware of the biases you sometimes find in science. It also helped me become a better communicator and be more aware of how easy it is to spread misconceptions.”

Why do we stare at people who are different?
The science of love
An interview with Sara Freeman on Emory's Neuroethics Blog

Friday, April 5, 2013

The 'dirty ecology' of 'Beasts of the Southern Wild'

Hushpuppy (Quvenshane Wallis) and Wink (Dwight Henry) adrift in a half-real, half-mythic world. (Twentieth Century Fox, 2012).

In Southern Spaces, an online interdisciplinary journal produced at Emory, Patricia Yeager of the University of Michigan writes about the "dirty ecology" portrayed in "Beasts of the Southern Wild." The 2012 "epic film about toxic inequality" mixes imagery of nature, man and trash, like a throwaway Styrofoam container filled with gator meat.

Below is an excerpt from Yeager's article, interpreting the underlying themes of the movie:

"This throwaway Styrofoam brings us to Beasts' other mythic register—its quest for a way to represent our species' relation to global warming. Styrofoam is made from oil, and images of acetylene torches, gas stoves, and gas engines remind us that although the film's characters are battered by the forces of global warming and their carbon footprint is small, creating a carbon-free democracy is not their concern.

"The citizens of the Bathtub practice a dirty ecology, making do with what they can salvage from other waste-making classes. When a Katrina-like storm savages their community, the damage is endless. A giant pig-beast knocks over power lines: these are animals who 'eat their own mommas and daddies.' In the Bathtub the carbon apocalypse is already upon us. Early in the movie, Hushpuppy's teacher raises her skirt; she shows a thigh tattooed with prehistoric aurochs—'fierce' creatures who signify that 'any day the fabric of the universe is going to unravel.' ...

"The Bathtub's houses are made from castaway metal and lumber, its people jettisoned by the currents of capitalism. It's too close to the water: cut off by a levy from the thing-creating world. The oil refinery looks at once mechanical and auratic; its white spires hover in the same place in the pictorial frame as the calving glaciers that start to rain down on the audience, and free child-eating aurochs—the mythic equivalents of carbon's rough beasts, their hour come round at last.

"These once-extinct, returning aurochs mark the movie's geologic concern, its interest in eras. Around 1750, humans switched from renewable energy to the large-scale use of fossil fuel—a shift in scale marking the beginning of a new era. Ten thousand years ago the Pleistocene or Ice Age gave way to the warmer Holocene, and civilization began in earnest. But our contemporary era, the Anthropocene, has speeded up our species' access to matter until we now create our own weather events, our own set of fractures. Humans are reborn as geologic agents, as the main cause of change for earth itself."

Read the whole article in "Southern Spaces." 

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