Wednesday, December 21, 2011

Trees and reality TV drive discovery in 2011

In 2011, flashes of inspiration made fundamental science at Emory seem almost easy. A hike in the woods sparked a breakthrough in number theory, while an episode of “American Idol” led to an insight about the human brain.

Actually, it takes a certain brilliance to find big ideas hiding amid trees and reality TV. To paraphrase Louis Pasteur, whether you are an athlete or a couch potato, chance favors a prepared mind.

Here’s a roundup of the hottest topics on eScienceCommons for 2011.

New theories reveal the nature of numbers: For centuries, some of the greatest names in math have tried to make sense of partition numbers, the basis for adding and counting. The eureka moment finally occurred when mathematicians were hiking through the fall foliage in north Georgia and noticed patterns in the trees and the switchback trail. Partition numbers are fractal, repeating in an infinite pattern, they suddenly realized.

Teen brains can predict pop song success: A neuroeconomist was watching “American Idol” with his two young daughters when a contestant started singing “Apologize” by One Republic. The song sounded familiar, and the scientist realized that he had used it in a study. That led to a re-analysis of brain-response data of teens listening to obscure songs. The results show that teen brain activity may help predict the popularity of music.

Dawn of agriculture took toll on health: Anthropologists confirmed that when populations around the globe started turning to agriculture around 10,000 years ago, regardless of the location or the types of crops, a similar trend occurred: The height and the health of the people declined. In modern times, the stature trend has reversed: The average human height is increasing, as food becomes increasingly commercialized and abundant. But is our health improving, in an era of obesity?

Anxious kids confuse ‘mad’ and ‘sad’:
Psychologists found that children suffering from extreme social anxiety are trapped in a nightmare of misinterpreted facial expressions: They confuse angry faces with sad ones. Non-verbal communication is a critical, but often overlooked, aspect of child development. The good news is that non-verbal communication skills can be improved at any age.

Chimps, bonobos yield clues to social brain: It’s been a puzzle why our two closest living primate relatives, chimpanzees and bonobos, have widely different social traits, despite belonging to the same genus. Now, a comparative analysis of their brains shows neuroanatomical differences that may be responsible for these behaviors, from the aggression more typical of chimpanzees to the social tolerance of bonobos.

Chemists reveal the force within you: A new method for visualizing mechanical forces on the surface of a cell provides the first detailed view of those forces, as they occur in real-time. Mapping such forces may help to diagnose and treat diseases related to cellular mechanics. Cancer cells, for instance, move differently from normal cells, and it is unclear whether that difference is a cause or an effect of the disease.

Hominid skull hints at later brain evolution: An analysis of a skull from the most complete early hominid fossils ever found suggests that the large and complex human brain may have evolved more rapidly than previously realized, and at a later time than some other human characteristics. While some features of Australopithecus sediba were more human-like, most notably the precision-grip hand, the brain was more ape-like.

Biochemical cell signals quantified for first time: Just as cell phones and computers transmit data through electronic networks, the cells of your body send and receive chemical messages through molecular pathways. The term “cell signaling” was coined more than 30 years ago to describe this process. Now, for the first time, physicists have quantified the data capacity of a biochemical signaling pathway and found a surprise – it’s way lower than even an old-fashioned, dial-up modem.

Mummies tell history of a modern plague:
Mummies from along the Nile are revealing how age-old irrigation techniques may have boosted the plague of schistosomiasis, a water-borne parasitic disease that infects an estimated 200 million people today. An analysis of the mummies provides details about the prevalence of the disease across populations in ancient times, and how human alteration of the environment may have contributed to its spread.

Polar dinosaur tracks open new trail to past: Paleontologists discovered a group of more than 20 polar dinosaur tracks on the coast of Victoria, Australia, offering a rare glimpse into animal behavior during the last period of pronounced global warming, about 105 million years ago. The discovery is the largest and best collection of polar dinosaur tracks ever found in the Southern Hemisphere.

Beer, bugs and brains: Hot topics in 2010
2010: A science odyssey

Friday, December 16, 2011

Skeletons point to Columbus voyage for syphilis origins

"The evidence keeps accumulating that a progenitor of syphilis came from the New World with Columbus' crew and rapidly evolved," says anthropologist George Armelagos.

By Carol Clark

Skeletons don’t lie. But sometimes they may mislead, as in the case of bones that reputedly showed evidence of syphilis in Europe and other parts of the Old World before Christopher Columbus made his historic voyage in 1492.

None of this skeletal evidence, including 54 published reports, holds up when subjected to standardized analyses for both diagnosis and dating, according to an appraisal in the current Yearbook of Physical Anthropology. In fact, the skeletal data bolsters the case that syphilis did not exist in Europe before Columbus set sail.

“This is the first time that all 54 of these cases have been evaluated systematically,” says George Armelagos, an anthropologist at Emory University and co-author of the appraisal. “The evidence keeps accumulating that a progenitor of syphilis came from the New World with Columbus’ crew and rapidly evolved into the venereal disease that remains with us today.”

The appraisal was led by two of Armelagos’ former graduate students at Emory: Molly Zuckerman, who is now an assistant professor at Mississippi State University, and Kristin Harper, currently a post-doctoral fellow at Columbia University. Additional authors include Emory anthropologist John Kingston and Megan Harper from the University of Missouri.

“Syphilis has been around for 500 years,” Zuckerman says. “People started debating where it came from shortly afterwards, and they haven’t stopped since. It was one of the first global diseases, and understanding where it came from and how it spread may help us combat diseases today.”

The history of syphilis, and society's reactions to the disease, have eerie parallels to the more modern story of HIV/AIDS.

"Syphilis was a by-product of two different populations meeting and exchanging a pathogen," says anthropologist Molly Zuckerman. "It was an adaptive event, the natural selection of a disease, independent of morality or blame."

The treponemal family of bacteria causes syphilis and related diseases that share some symptoms but spread differently. Syphilis is sexually transmitted. Yaws and bejel, which occurred in early New World populations, are tropical diseases that are transmitted through skin-to-skin contact or oral contact.

The first recorded epidemic of venereal syphilis occurred in Europe in 1495. One hypothesis is that a subspecies of Treponema from the warm, moist climate of the tropical New World mutated into the venereal subspecies to survive in the cooler and relatively more hygienic European environment.

The fact that syphilis is a stigmatized, sexual disease has added to the controversy over its origins, Zuckerman says.

“In reality, it appears that venereal syphilis was the by-product of two different populations meeting and exchanging a pathogen,” she says. “It was an adaptive event, the natural selection of a disease, independent of morality or blame.”

 A biopsy of Treponema pallidum spirochetes in tissue. In 2008, anthropologist Kristin Harper completed a comprehensive comparative genetic analysis of syphilis's family of bacteria. The results further supported the Columbus theory for its origins. (Image courtesy of CDC.)

Armelagos, a pioneer of the field of bioarcheology, was one of the doubters decades ago, when he first heard the Columbus theory for syphilis. “I laughed at the idea that a small group of sailors brought back this disease that caused this major European epidemic,” he recalls.

While teaching at the University of Massachusetts, he and graduate student Brenda Baker decided to investigate the matter and got a shock: All of the available evidence at the time actually supported the Columbus theory. “It was a paradigm shift,” Armelagos says. The pair published their results in 1988.

In 2008, Harper and Armelagos published the most comprehensive comparative genetic analysis ever conducted on syphilis’s family of bacteria.
The results again supported the hypothesis that syphilis, or some progenitor, came from the New World.

A series of 18th-century prints called "A Harlot's Progress" begins with innocent country girl Molly, left, arriving in London, where she is immediately procured by a madame. The lesions on the madame's face are the tell-tale signs of syphilis, which Molly tragically dies of in the last print of the series. Read more about this morality tale here.

But reports of pre-Columbian skeletons showing the lesions of chronic syphilis have kept cropping up in the Old World. For this latest appraisal of the skeletal evidence, the researchers gathered all of the published reports.

They found that most of the skeletal material did not meet at least one of the standardized, diagnostic criteria for chronic syphilis, including pitting on the skull known as caries sicca and pitting and swelling of the long bones.

The few published cases that did meet the criteria tended to come from coastal regions where seafood was a big part of the diet. The so-called “marine reservoir effect,” caused by eating seafood which contains “old carbon” from upwelling, deep ocean waters, can throw off radiocarbon dating of a skeleton by hundreds, or even thousands, of years. Analyzing the collagen levels of the skeletal material enabled the researchers to estimate the seafood consumption and factor that result into the radiocarbon dating.

“Once we adjusted for the marine signature, all of the skeletons that showed definite signs of treponemal disease appeared to be dated to after Columbus returned to Europe,” Harper says.

“The origin of syphilis is a fascinating, compelling question,” Zuckerman says. “The current evidence is pretty definitive, but we shouldn’t close the book and say we’re done with the subject. The great thing about science is constantly being able to understand things in a new light.”

Putting teeth into the Barker hypothesis
Dawn of agriculture took toll on health
Ancient beer brewers tapped antibiotic secrets

Wednesday, December 14, 2011

Creativity: Science education's missing link

By Carol Clark

Memorizing facts and formulas may be the foundation of a good science education, but creativity also needs to be taught and encouraged in undergraduate classes, says Robert DeHaan, professor emeritus in Emory's School of Medicine.

An editorial by DeHaan, entitled “Teaching Creative Science Thinking,” will appear in the journal Science on December 16. DeHaan’s career as a researcher of cell biology, a professor of medicine and a science advisor for educational studies spans five decades.

“It’s unfortunate that we often teach science as if science only deals with neat problems with a single answer, and a single path to get to that answer,” DeHaan says. “But when you walk into a lab, you don’t know what problems you’re going to face, or how you’re going to arrive at solutions.”

Creativity is the most complex and abstract of the higher-order cognitive skills, according to the classification system known as Bloom’s taxonomy of learning skills. Other higher-order thinking skills such as analysis, synthesis and abstraction are also key to solving ill-structured, or “messy,” problems in science, DeHaan says.

And yet, he adds, a recent national sample of 77 undergraduate life science courses, taught by 50 different instructors, found that fewer than 1 percent of the items on tests and quizzes required students to use any of these higher-level skills.

DeHaan advocates moving beyond just lecturing in science classes and getting students engaged in active learning modes that foster peer-to-peer reasoning and creative thinking for complex problem solving.

“Students need to be reminded that there may be other ways to view a problem than the way it is presented,” DeHaan says. “And they need to learn to generate many ideas about possible solutions before beginning to evaluate which of them may be best.”

Quick, how many uses can you think of for a plastic bottle? It's a simple way to test your creativity. Click here to see one of the most creative answers ever to this question, currently hanging on the Emory Quad.

Creative science thinking should not only be taught, it should be tested, he adds. A simple method, based on the Torrance Test of Creative Thinking, is to ask students to list all of the possible uses for an object such as a plastic bottle.

When DeHaan gives this problem to students, their lists range from four or five ideas to dozens. “Most of the ideas will be similar, but when you get a response that is limited to 5 percent or less in a group of 100 students, that’s an original idea,” he says.

More research is needed, DeHaan says, to find effective strategies to prepare the next generation of scientists for the complex, interdisciplinary problems that they will need to tackle.

“If more students learn to think like creative scientists, it will be worth the effort,” he concludes.

How a hike in the woods led to a math 'aha'
Cultivating brains for science
Math's in your cards, so deal with it
An idea that shifts with wind, water and light

Credits: Top and middle photos by Bottom photo by Carol Clark.

Friday, December 9, 2011

An idea that shifts with wind, water and light

Art meets science on the Emory Quad, in the form of "Piedmont Divide."

By Carol Clark

As you approach the Emory Quadrangle on a sunny afternoon, you see what looks like a giant crystal chandelier floating amid the canopy of the oak trees. As you walk beneath it, the swaying “chandelier” appears as ephemeral as a cloud, or a seeding dandelion.

One thing that Emory’s new sculpture, called “Piedmont Divide,” does not resemble is the thousands of recycled plastic bottles that comprise it.

“I didn’t expect the sort of precious quality of the material, just how much the sunlight and wind would do this,” says the sculpture’s creator, environmental artist John Grade.

“It was remarkable to see the plastic bottles change from trash into these things that look so organic,” says Julia Kjelgaard, chair of the visual arts department.

The visual arts department invited Grade (pronounced “grotty”), a Seattle-based artist who draws from science and nature, to create a piece for Emory. After a whirlwind two-day visit, and many meetings with faculty, Grade decided to do a piece that would reflect the campus environment, as well as Emory’s research into West Nile virus and global water sustainability.

Grade returned to his Seattle studio to ponder what material he should use to tie all of those themes together. “It was an ‘aha’ moment,” Grade says of the idea of recycling plastic drinking bottles. “I realized that there was this relationship with Coca-Cola supporting the university, and I thought about how to use that product and transform it in some way for this environment.”

In November, Grade returned to Emory with two assistants: Seattle sculptor Dilyara Maganya and civil engineer Travis Stanley. Over 13 days, the three enlisted volunteers from across campus to melt down thousands of discarded drinking bottles and help assemble “Piedmont Divide.”

John Grade at work on the Emory Quad.

“I’ve had this desire to make something with many people,” he says of the group effort. “So I don’t have full control, and you actually have a social contract, a group of people crafting something together and figuring it out along the way. Your end result may not be perfectly made, but you have all these interesting decisions from different people along the way that completely change it.”

Each plastic bottle was cut into a spiral and melted into a long, curving stalk that curled into a dainty little cup at the end. The cups are designed to hold a few drops of rainwater. Click here to see a video of how the sculpture was made.

A tornado siren went off as Grade was standing on a 20-foot platform on the Quad, putting the final touches on the piece. He watched as a gentle rain began filling the thousands of little cups, and the ephemeral character of the sculpture shifted slightly as it took on the weight of the water. The tiny pools of water suspended by the sculpture are an allusion to incubators for mosquitoes.

On a far side of campus from the Quad’s floating chandelier, the second half of “Piedmont Divide” is set in the lake of Lullwater woods. There, the plastic stalks rise from the water like crystal reeds.

Grade says he wants “Piedmont Divide” to help people make connections, between different environments and between different water systems, and how both nature and man use them.

One of Grade’s greatest strengths as an environmental artist may be that he is not afraid of failure. He actually enjoys fielding the curve balls that nature throws at him.

He describes a sculpture he made in Arizona, elevated amid trees and made of edible bits that birds could eat. “The idea came to me because I feel like there’s a lot of ego involved inputting an object out into a landscape, when a lot of times the landscape is very interesting in and of itself,” Grade says. “So I liked the fact that these birds would pick apart this form that I made, and then just shit it all across the mesa.”

After the piece was installed, however, rodents crawled onto the sculpture’s guy wires and annoyed the birds to the point that they wouldn’t eat. “I thought, ‘Do I roll with what the environment comes back to me with, or try to change this,’” Grade recalls. In the end, a birder suggested that he spread a liquid form of jalapeno over the piece, which would thwart mammals but not birds.

As the “Piedmont Divide” shimmers on the Emory campus through spring, it will be interesting to see how the vision keeps shifting in the wind, water, light and creative spirit of a university.

Hal Jacobs contributed to this story through his video reports.

From Atlanta to Accra: The growing sewage problem
Add environmental artist to your resume
Sewage raises West Nile virus risk

Friday, December 2, 2011

Chemist recalls history of AIDS drugs

Every December 1 is World AIDS Day, a chance to unite in the fight against HIV, and to reflect on how the epidemic has changed medicine and society.

In 1987, AZT became the first drug for treating HIV infections. “There were issues in the supply of AZT at the time,” recalls Emory chemist Dennis Liotta. “And there were also issues around rapid development of resistance to the drug.”

Liotta’s lab decided to tackle the problem of coming up with a better treatment.

“We came in with a completely uninformed, but fresh, look at the problem,” Liotta recalls. “We had some very efficient ways of preparing compounds. We came up with a novel idea, and it actually worked the first time we tried it.”

The new approach resulted in two important anti-virals for HIV treatment. “First, they had limited side effects as compared to other drugs being used to treat HIV,” Liotta says. “That’s important, because people have to take these drugs every day of their life. The second feature is that they have good resistance profiles. When given in combination, they can dramatically suppress viral replication.”

The breakthroughs were a major game-changer for HIV, allowing infected people to live relatively normal lives by sticking to a treatment regimen.

About 94 percent of people who are being treated for HIV in the United States take one of the anti-viral drugs developed by Liotta’s team.

“Part of our success was due to coming at the problem from a different perspective than others,” Liotta says. “Another part was due to our skills in organic synthesis. And a third part was being in the right place at the right time. As Louis Pasteur said, ‘Chance favors the prepared mind.’”

Ryan White: A leader forged by AIDS
AIDS: From a new disease to a leading killer

Thursday, December 1, 2011

Throwing linked to intelligence in chimps

From CBS News:

"Any zoo-goers so unlucky as to be on the receiving end of a poop-tossing chimpanzee may be excused for taking a dim view of that particular form of monkey mayhem. But don't let the gross-out aspect of the situation cloud your judgment about the perpetrator: New research suggests that a primate's ability to throw an object is actually a solid indicator of intelligence.

"Bill Hopkins of Emory University and his collaborators make that argument in a new paper published in the Philosophical Transactions of the Royal Society B. Among other things, they find major overlap between brain areas which distinguish right- and left-handed throwing chimpanzees and the regions of the cortex involved in language processing by humans. The researchers concluded that the chimps which were better throwers also possessed more developed left brain hemispheres, the area where we process speech."

Read the full article at CBN News.

Gestures may point to speech origins
Brain trumps hand in Stone Age tool study
Top 10 facts about non-verbal communication