Friday, December 16, 2016

Mind over matter: Her interest in the brain led her to computer science

"Your brain can store all of your experiences at some level. It doesn’t store every detail," says Emory computer scientist Avani Wildani. "If we can get a better idea of how information storage and reductionism work in the brain, perhaps we could translate that to a computer framework." (Photos by Ann Borden, Emory Photo/Video)

By Carol Clark

Avani Wildani, an Emory assistant professor of Mathematics and Computer Science, got her first computer when she was three years old. A TI-99 from Texas Instruments, it was the first 16-bit personal computer and known for its eccentricities.

“It spoke to you in this very robotic voice,” Wildani says. “It was a really hot thing at the time for the computer to talk to you.”

Wildani was born in Mechanicsburg, Pennsylvania, to immigrants from the state of Gujarat in India. The oldest of three children in a close-knit family, she did not start speaking English until she began school.

Biology fascinated her from an early age, particularly mysteries of how the brain works. “I’m interested in how we think about things,” she says, “and what information means for the mind.”

One focus of her current research is the looming problem of information storage: The disconnect between our growing ability to gather digital information – on everything from human genetics to deep space – and our limited technology and resources for keeping and managing all of that data.

Wildani originally aspired to be a physician, like her father. “He steered me into a more sedentary direction,” she says.

Her father realized that she needed a job where she could sit because she was born with osteogenesis imperfecta, or brittle bone disease. The disorder causes bones to break easily and Wildani endured hundreds of breaks and countless medical procedures as a child.

In September, she was hit by a car while crossing an Atlanta pedestrian crosswalk in her wheelchair, an incident that fractured her legs in seven places. She continued to work while recovering in her Druid Hills home.

Light streams into the modernistic home through large, plate-glass windows, which look out onto wooded terrain. Evidence of Wildani’s many hobbies is strewn about the house – a full set of drums, a telescope that she built from scratch, her pencil sketches, photos of her kayaking adventures. As she settles in for an interview in her home office, she offers a visitor a tray of Indian pastry sweets.

Below are some excerpts from the interview.

Q. What was it like to spend so much time in hospitals as a child?

Wildani: It wasn’t that bad. It would take me about 20 to 30 minutes a day to do my school homework, and I could still keep up. So the rest of the time I got to lie around, eat ice cream, and read. In fourth grade, I got through all of Nancy Drew.

It was probably harder on my parents. As a child, I just took it for granted that my parents would be at the hospital at 3 am with Indian food because I didn’t like American food. My mother would make me treats like khandvi – chickpea flour mixed with lemon and yogurt, rolled out and fried. It’s super good! Gujartis are like the Southerners of India: We fry everything.

Playing computer games "allows you to try something and fail in a safe way," says Wildani, who also plays the drums.

Q. Did you also spend a lot of time on a computer?

Wildani: Yes, I started learning about programming as soon as I learned to read, at age 3. I used LOGO, an educational programming language for children. It’s all about drawing pictures. In fact, the first time I taught Python to college students I had them integrate it with LOGO to make flowers for their mothers on Mother’s Day. People really loved that assignment and ran with it. They did all sorts of amazing animations.

Growing up, I also enjoyed computer games. I played a lot of King’s Quest, an early strategy game designed by Roberta Williams, who is one of my inspirations. King’s Quest was full of puzzles and the puzzles were hard. It teaches perseverance.

Q. So you don’t consider computer games a waste of time? 

Wildani: No, not at all. They inspire a lot of people. I would say that everybody I knew during my college years played a lot of computer games as a kid. Even if you don’t go into computer science or technology for a career, computer games allow you to try something and fail in a safe way. You don’t die and you keep getting better the more you try. It also teaches team building. I think playing computer games is in some ways like playing a sport. I would be interested in studies that look at how the motor cortex changes if you play a lot of computer games.

Q. Maybe all those computer games you played account for the can-do spirit you embody in your real life. 

Wildani: I’m not afraid to try things. I fail sometimes, but I have a really supportive family. I have a pretty solid mat to fall on when I screw up.

Q. How does your interest in the human brain relate to your research into computer data storage? 

Wildani: Your brain can store all of your experiences at some level. It doesn’t store every detail. In fact, it forgets things on purpose, pruning data and keeping what you need to make sense of the world, stringing together related ideas and forming memories that it can then retrieve. One theory is that the hippocampus acts like a kind of card catalogue where the brain can look up the place where it has stored different pieces of data.

The brain does all this using very little power, only around 60 watts, and with a high fault rate. Neurons are dying all the time and synapses are breaking down. In fact, stroke patients can lose a significant part of their hippocampus and still function.

If we can get a better idea of how information storage and reductionism work in the brain, perhaps we could translate that to a computer framework. We’re using vision classification as a bio-model to run simulations and try to figure out how the brain makes tradeoffs between network size, power and reliability.

"We’re losing information about hidden things that we don’t already know to look for," Wildani says. "That’s why it’s critical now to come up with new ways to store large volumes of data."

Q. Why is it important to understand this? 

Wildani: People are creating entire digital identities of family photos, emails, receipts – all kinds of data. Some of it is data that people want to keep and some of it is just stuff that gets saved unintentionally. You can think of all our personal collections of data like junk-filled closets that we store in “clouds.”

But what many people don’t realize is that the clouds are actually physical computer-data centers. And they require space, electricity and people to maintain them and to run them.

The centers house the physical storage devices for all the data. Disks, for instance, save data using tiny dots, called bits. But there is a limit to how close these dots can be, based on physics. They can only go to a certain resolution and no lower. Flash drives don’t rely on that sort of density, but they are not as reliable. And a disk only lasts about five years. So you have to have a plan to move data around between different devices.

We make a lot more information than we have anywhere to put it. Right now, Internet traffic is annually generating zetabytes of information and that’s projected to go up to yottabytes by 2020. [A yottabyte equals 1,000,000,000,000,000,000,000,000 bytes.]

We have this huge mess of data collected across time. How do we decide what’s important and what’s not? How long should we keep it? Who will pay for keeping it over time? There are things we archive with intention, like family photos, and things that we archive without really meaning to, like random receipts and emails.

Q. Could it just be a matter of everyone throwing out their digital “junk” and making space? 

Wildani: The issue is much bigger than that. We can’t always know what is going to be important in the future. The tapes of the early “Dr. Who” episodes, for example, got written over years ago because the BBC didn’t think they were important.

In the future, if you get sick with something, it might be useful to pull up the medical records of your great grandparents. Or maybe not. You might also want to store a genome analysis of your family for the future.

My favorite example of “junk” data that became useful is a photograph that was taken in 1900 of a random patch of sky. Decades later, cosmologists found this photo in a drawer and saw that it contained a pre-supernova. By comparing it to modern-day photos of the same patch of sky, they were able to compute a more exact rate for the expansion of the universe.

We have much more powerful telescopes today but not enough storage to save all the data these instruments are capturing. The same is the case for CERN, home of the Large Hadron Collider, which is gathering large datasets on sub-atomic particles. CERN is only able to save the data that is being experimented on now.

We’re losing information about hidden things that we don’t already know to look for. That’s why it’s critical now to come up with new ways to store large volumes of data.

Q. How do you feel about the scarcity of women in computer science? 

Wildani: When I was an undergraduate, I would have felt more comfortable if there had been more women in the room when I was asking a basic, technical question. But I had no choice. I was the only female in most of my computer science classes. And the default assumption for women is that you’re not competent. You have to prove yourself.

The traditional image of a computer science major is a guy with a beard who drinks a lot of Mountain Dew and spends a lot of time ranting on online forums. There are definitely some people who fit that personality type, but also many people who don’t. And some of them are so far from it that they don’t feel welcome and they leave.

I knew a woman in graduate school who was great at computer science, great at math, but she was also tall and blonde. She got tired of dealing with harassment and people who thought she was the receptionist. Eventually, she decided to go into a different field.

And yet, we need more people and different perspectives in computer science. The salaries for computer engineering are high because there are not enough people to fill the jobs.

I developed a web site (Project Hypatia) to highlight important research by women in computer science. I think it’s important to make it clear that women are not just asking for equality, but leading teams, doing impressive science and getting results.

BRAIN grant to fund study of how the mind learns

Tuesday, December 6, 2016

How will the shifting political winds affect U.S. climate policy?

Emory seniors Emily Li (left) and Jennie Sun were part of an Emory delegation to Marrakech, Morocco, in November for a U.N. Climate Change Conference. Shortly after the event began, Donald Trump, who has called climate change a hoax, won the U.S. presidential election. “We need to think about how to move forward," Li says, "because focusing on the negatives is ultimately not going to be useful.”

By Carol Clark

“No U.S. president has been as vocal about climate change, or as focused on mitigating it, as Barack Obama,” says Eri Saikawa, an assistant professor in Emory’s Department of Environmental Sciences and an expert in public policy and the science of emissions linked to global warming.

President-elect Donald Trump, however, has repeatedly called climate change a hoax.

“The concern about how Trump will deal with climate change is worldwide,” Saikawa says. “We all share the same atmosphere and the United States is a leading emitter of greenhouse gases. The impacts of global warming will affect the entire planet.”

Among Obama’s initiatives is the U.S. Clean Power Plan – which established the first national carbon pollution standards for power plants. U.S. leadership was also instrumental in the historic Paris Agreement to combat climate change. The 2015 agreement, organized by the United Nations’ Framework Convention on Climate Change (UNFCC), brought more than 190 countries together to commit to a framework to reduce greenhouse gas emissions.

“The Paris Agreement is an amazing achievement, and there was so much momentum and excitement surrounding it,” Saikawa says.

On November 7, delegates from around the world gathered in Marrakech, Morocco, to hammer out details resulting from the Paris Agreement. Saikawa headed a 10-member Emory delegation to Marrakech for the two-week event, known as the U.N. 22nd Conference of the Parties (COP 22). (Emory, one of the few universities approved as an official U.N. observer by the COP, also sent a delegation to the Paris talks last year.)

Emory’s Marrakech delegation included six students and three staff members. They split into two teams, with half participating at COP 22 during the first week and the other half during the second. 

Emory delegates on the ground in Marrakech, including senior Emily Li (front left), and, from upper left: Kate Lee (clinical fellow and staff attorney for the Turner Environmental Law Clinic), sophomore Maya Bornstein, senior Jennie Sun and Tyler Stern (an Emory grad who is now a Residence Life Fellow).

Emily Li, a senior majoring in environmental sciences and English, was there when the U.S. presidential election results were announced.

“Everyone was in shock,” Li says, of the surprise victory by Trump. “You could tell which delegates were from the U.S. because they just looked so tired that morning. The U.S. press office was total chaos.”

Li also struggled to take in the turn of events. “It was discouraging at first,” she says. “I’m really passionate about mitigating climate change and to have a national leader who doesn’t recognize it as an important issue is really disheartening.”

During the election campaign, Trump threatened to ax the Clean Power Plan and to pull the United States out of the Paris Agreement. After winning, Trump seemed to soften his stance somewhat, saying he would keep an “open mind” about the agreement. But he tapped Myron Ebell, a well-known climate-science denier, to lead his administration’s revamping of the Environmental Protection Agency (EPA).

Li summed up the post-election mood at COP 22 in a blog post called “Talking about the Elephant in the Room.” You can read it, along with posts by other members of the Emory delegation, on the Emory Climate Organization (ECO) web site, founded by students focused on understanding climate change.

The mood at COP 22 soon shifted from shock to a sense of renewed urgency. “A lot of the younger delegates, in particular, were saying how the Trump administration could help bring people together and motivate more engagement and action,” Li says. “We need to think about how to move forward because focusing on the negatives is ultimately not going to be useful.”

Local initiatives are more important than ever, she noted. For her senior thesis in environmental sciences, Li is zeroing in on ways that climate change may affect public health in Atlanta. “I’m doing a lot of research, looking at different studies to learn the scientific consensus. I’m also interviewing policy makers and people affected by events like the drought and the recent wildfires,” she says.

She plans to translate the science into engaging stories that she will post to a public web site, along with possible solutions. “I want to help communicate the direct effects of climate change on public health in Atlanta, so people living here can better understand the potential impact on themselves and their children,” Li explains. “I think that the more local an issue is, the more people tend to care about it.”

Geoff Martin, who is working on a master degree in environmental sciences, participated in the second week of COP 22. “In the month leading up to Morocco, I was really excited,” he recalls. “The Paris Agreement had finally gotten things moving in the right direction and I was going to this great event, COP 22, the first step towards implementation.”

The election results took the wind out of his sails, but only momentarily. “Being at the conference helped me regain my perspective,” Martin says. “People from all different levels and areas – government officials, those from the private sector and from non-governmental agencies – found reasons to still be hopeful.”

One of the major take-home messages for him is that the international community is going to continue to move forward in combating climate change, with or without the United States.

Another theme he heard repeatedly was that governing is a lot different from campaigning. “Trump will likely find that many of the things he said he was going to do during his campaign, like dismantle the EPA and cancel the Paris Agreement, may be easier said than done,” Martin says.

He also draws hope from the fact that the energy market is shifting. “The price of renewable energy keeps going down, making it increasingly competitive with fossil fuels in many places,” he says. “Regardless of government policy, the market could continue to drive a transition towards renewable energy.”

Martin is at work on a thesis, focused on analyzing the effectiveness of state-level climate and energy policies. He agrees with Li that the election of Trump could serve as a wake-up call for those concerned about climate change to take action at the local level, and not wait for the federal government to take the lead.

“Lots of talks at COP 22 were focused on sub-national efforts to mitigate climate change, not just in the United States, but throughout the world,” Martin says. He cites the Regional Greenhouse Gas Initiative, a successful cap-and-trade program for the power sector comprising nine U.S. states in the northeast.

The recent victory by the Standing Rock Sioux Tribe to block the $3.7 billion Dakota Access pipeline is another hopeful sign, Martin says. “Their victory was entirely a result of grassroots activism,” he says. “It shows how, if people really care about an issue and come out to protest and pressure government officials, they can make a difference.”

Peachtree to Paris: Emory delegation headed to U.N. climate talks

Thursday, November 24, 2016

The top 10 policies needed now to protect pollinators

Bee thankful: “If you enjoyed a bountiful Thanksgiving Day dinner, you should give thanks to pollinators,” says Emory biologist Berry Brosi.

By Carol Clark

Scientific experts from eight different countries developed a list of the top 10 policies needed to reverse the decline of pollinators crucial to the world’s food supply.

The journal Science is publishing the recommendations for the global community in a forum article, “10 Policies for Pollinators.” The recommendations will be presented at the United Nations Convention of the Parties on Biological Diversity (CoP13), to take place in Mexico December 4 to 17.

“If you enjoyed a bountiful Thanksgiving Day dinner, you should give thanks to pollinators,” says Berry Brosi, a biologist and ecologist in Emory University’s Department of Environmental Sciences and a co-author of the article.

Brosi cites the first policy recommendation on the list as the most concrete and actionable: Better pesticide regulatory standards.

He adds that several of the recommendations related to sustainable agriculture more broadly include making chemical control for insects and other pests a last resort.

“Especially in light of the emergence of the Zika virus, and widespread public concern about mosquito-borne diseases, we are likely to see increased demands for pesticide use,” Brosi says. “Mosquito control is, of course, important, but we also need to be thoughtful about what kinds of pesticides we use and how we use them. We should carefully consider the impact on pollinators and other biodiversity.”

The Environmental Protection Agency is currently reviewing a class of insecticides commonly used in agriculture, neonicotinoids, which have been linked to wide-scale bee declines and impacts to other pollinator species by a range of scientific studies.

"Neonicotinoids are known to kill bees and other insect pollinators in very low doses, and to cause behavioral disruptions in even minute concentrations, measured in parts-per-billion," says Brosi, whose research focuses on both managed honeybees and wild bees.

In 2014, Emory began taking steps to eliminate the use of neonicotinoid-based pesticides and pre-treated plants on its campus grounds, the first university to do so worldwide.

The EPA’s review of the safety of neonicotinoids is not due until 2017.

The complete list of recommended policies for pollinators is as follows:

1. Raise pesticide regulatory standards
2. Promote integrated pest management
3. Include indirect and sublethal effects in GM crop risk assessments
4. Regulate movement of managed pollinators
5. Develop insurance schemes to help farmers
6. Recognize pollination as agricultural input in extension services
7. Support diversified farming systems
8. Conserve and restore “green infrastructure” (a network of habitats that pollinators can move between) in agricultural and urban landscapes
9. Develop long-term monitoring of pollinators and pollination
10. Fund participatory research on improving yields in organic, diversified and ecologically intensified farming

The policy recommendations follow a United Nations warning in February that pollinators were under threat. Brosi was among 77 international experts who worked on that report, the first global pollinator assessment for the U.N.’s Intergovernmental Panel for Biodiversity Ecosystem Services (IPBES).

The assessment found that more than 40 percent of invertebrate pollinator species, particularly bees and butterflies, face extinction. And 16 percent of vertebrate pollinators are under threat. The issue is critical to agricultural, economics and the health of humans and ecosystems: 75 percent of the world’s food crops depend on pollination by at least one of 20,000 species of pollinators, including bees, butterflies, moths, wasps, beetles, birds, bats and other vertebrates.

Pollinators vital to food supply facing extinction, U.N. report warns 
Emory to ban bee-harming pesticides, protect pollinators

Monday, November 21, 2016

Learning to love our bugs

Each of us is a mobile ecosystem, teeming with trillions of living organisms. (Illustration by Giula Ghigini) 

By Jerry Grillo
Emory Medicine

They live on us and inside us, surround us like an invisible cloud, maintain and sustain us, ignore us, occasionally attack and kill us, and, ultimately, define us.

The human microbiome is made up of bacteria, fungi, viruses, and the like, and they cover every surface of our bodies.

"These microbiota are mostly in your gut, but also in your mouth, on your skin, in your lungs," says Emory biologist Nicole Gerardo. "They're playing critical roles in how you interact with the environment, how you process food, how you fight off pathogens, how you interact with drugs.

"Some of our remarkably fertile microbes are identical to those that live in other humans. But many are a distinct reflection of our individual experiences, shaped by who or what we've touched, where we've been, what we've breathed, and what we've consumed.

"Research interest in the human microbiome is exploding now," says Gerardo, who gave the introductory presentation at Emory's first microbiome symposium in November.

Spurred on by ambitious efforts like the National Institutes of Health's Human Microbiome Project, such research is demystifying the role of our myriad microbial passengers.

"It's like we're entering a new frontier of science, something that was basically ignored by medicine for a long time," says infectious disease researcher David Weiss, director of Emory's Antibiotic Resistance Center. "We're really at the beginning of studying all this, but I do think that in our lifetime, we'll be able to monitor each person's microbiome and intervene to improve their health. Looking at what type of bacteria we have and how resistant or sensitive they are to drugs will be an important part of health care. Most of the bugs we tote around are helpful, but they can also be ticking time bombs."

We may be able to someday diffuse the situation, replacing pathogenic microbes with a friendlier variety.

"There's great promise in manipulating the microbiome, in actually changing it," says geneticist Michael Zwick. "Actually, it's already happening."

Read the whole article in Emory Medicine.

What aphids can teach us about the microbiome and the immune system

Monday, November 14, 2016

Companies pushing 'toddler milk' for 'growth' need oversight, experts warn

"Parents are commonly concerned about the size of their children and how well they are doing developmentally," says Emory's Michelle Lampl, MD, PhD, adding: "Not all kids who are smaller than average have a problem."

By Carol Clark

Liquid-based nutritional supplements, originally formulated for malnourished or undernourished children, need more regulatory oversight as they are increasingly marketed to promote growth in children generally, warn researchers at Emory University.

The journal Healthcare published their commentary article, citing the lack of scientific evidence to support marketing claims of the benefits for growth of giving healthy children liquid-based nutritional supplements, commonly known as “toddler milks.”

“A plumper baby is not necessarily a healthier baby,” says Michelle Lampl, who is the lead author of the article, director of the Center for the Study of Human Health at Emory University and an internationally recognized expert in human growth.

In fact, toddler milk supplements may actually be doing harm by fueling rapid, unnecessary weight gain in young children in the midst of a global obesity epidemic, she adds.

She notes that the liquid supplements may have as much as 240 calories per serving and have the potential to turn a healthy, lean toddler into an overweight one. “Healthy developmental growth does not mean gaining weight and getting fat,” she says. “It is primarily measured by whether a child is growing a stronger, longer skeleton.”

Liquid-based nutritional supplements fall into a regulatory loophole, because the Food and Drug Administration (FDA) does not consider supplements to be a drug or a “conventional” food. “When a mother goes into a store and sees a toddler milk supplement on a shelf, she has no idea that it falls into a less rigorous FDA category than those covering so-called conventional food and medicine,” Lampl says. “We have a product aimed at a vulnerable population – infants and young children – that does not have adequate oversight.”

Co-authors of the commentary article are: Meriah Schoen, a research assistant at Emory’s Center for the Study of Human Health and a graduate student focused on nutrition at Georgia State University; and Amanda Mummert, who recently received a PhD in Anthropology from Emory's Laney Graduate School.

The commentary appears in a special issue of Healthcare, dedicated to the physician-scientist David Barker, who died in 2013. He originated the Barker Hypothesis, also known as the Developmental Origins of Health and Disease model, linking fetal and early infant experiences to an individual’s health status across the lifespan.

“David Barker opened the door to the importance of early influences, including nutrition and other environmental factors, for lifelong health,” Lampl says. “He believed that we have an ethical responsibility to ensure that the next generation is as healthy as it can be.”

Companies have marketed infant formulas for decades. In 1981, however, the World Health Organization (WHO) voted to recommend banning marketing of formulas for babies under six months, since the formulas were associated with lower rates of breastfeeding, and increased disease and malnutrition in the developing world.

Countries around the world adopted the rules and breastfeeding rates went up globally. The formula industry responded by focusing on toddler milk supplements, aimed at children ages six months and up.

Liquid-based supplements containing vitamins and minerals may be beneficial to children that are malnourished, or suffering from chronic diseases that prohibit their ability to consume solid foods, Lampl says. The problem, she adds, is that toddler milks have grown into a multi-billion-dollar industry that is expanding internationally to encompass healthy children.

Rapidly boosting the weight of children who are simply smaller than average but healthy could have lifelong consequences, she says. Barker, for instance, found a direct link to higher rates of metabolic disorders among individuals who were born relatively small and grew rapidly in the first few years of life.

“Parents are commonly concerned about the size of their children and how well they are doing developmentally,” Lampl says, adding that the growth charts used in pediatrician offices are often misunderstood. “Not all kids who are smaller than average have a problem.”

Busy mothers on the go, who may be consuming “energy drinks” and liquid supplements themselves, are primed to buy toddler milk for young children under the assumption that they are healthy choices, particularly for children who may be picky eaters.

“Although it can take a picky eater up to 20 times of trying a food to decide if they like it, most mothers offer a food fewer than five times before switching to something more convenient,” Lampl says. “It’s much easier to hand your child a sugary ‘toddler milk,’ thinking it’s healthy and it helps them grow.”

The WHO is set to consider recommendations concerning calorie amounts and ingredients for liquid-based nutritional supplements marketed to toddlers and older children during a meeting in early December.

Those recommendations will not have teeth, however, and it will be up to individual governments whether they decide to adopt them and enforce them.

“We are really behind when it comes to regulatory oversight for the marketing of these supplements, and for rigorous scientific research showing the impact of their widespread use on children,” Lampl says.

Support mothers to curb the global rise in chronic diseases
Grandma was right: Infants wake up taller

Tuesday, November 8, 2016

Emory's Rolosense wins bronze in Collegiate Inventors Competition

Emory graduate student Aaron Blanchard, left, and Kevin Yehl, who recently received his PhD in chemistry from Emory, were awarded bronze medals at the recent Collegiate Inventors Competition in Washington D.C. (Photo by the National Inventors Hall of Fame.)

By Carol Clark

Emory University’s Rolosense – the first rolling DNA motor – took the bronze medal in the graduate division of the 2016 Collegiate Inventors Competition, held recently in Washington D.C.

The Rolosense, and its application as a chemical sensor, was developed in the lab of Emory chemist Khalid Salaita by his students Aaron Blanchard and Kevin Yehl. Blanchard is a PhD student in Emory’s Laney Graduate School and the Coulter Department of Biomedical Engineering (BME) at Georgia Tech and Emory, while Yehl recently received his PhD in chemistry from Emory.

The Rolosense is the biological equivalent of the invention of the wheel for the field of DNA machines. “It’s a completely new approach at using DNA motors for sensing and diagnostics,” Yehl says. “We now hope to keep broadening the scope of the technology and really prove it out in the field.”

The Rolosense is 1,000 times faster than other synthetic DNA motors. Its speed, which is powered by ribonuclease H, means a simple smart phone microscope can capture its motion through video.

Watch a video to learn more about the rolling DNA motor:

The researchers have filed an invention disclosure patent for the concept of using the particle motion of the rolling molecular motor as a sensor for everything from a single DNA mutation in a biological sample to heavy metals in water. It offers a way of doing low-cost, low-tech diagnostics for researchers working in settings with limited resources, or for consumers themselves.

Yehl and Blanchard were one of six teams of graduate students that competed in early November in the finals at the National Inventors Hall of Fame in Washington D.C. The Collegiate Inventors Competition is considered the foremost program in the country encouraging invention and creativity in undergraduate and graduate students. The entries of the elite student teams represent the most promising inventions from U.S. universities.

The judges included inductees to the National Inventors Hall of Fame, officials from the U.S. Patent and Trademark Office and scientists from the global healthcare firm AbbVie.

“It was really cool to meet students from the other teams, and also the judges, to get their feedback,” Yehl says.

His main takeaway message: Keep on inventing.

Yehl is taking that advice to heart. In his new position as a post-doctoral associate in a synthetic biology lab at MIT, he’s now working on novel therapeutics to target drug resistant bacteria.

Blanchard agrees that a highlight of the competition was networking with the other competitors and the judges. “Several of the judges encouraged me to focus on areas of research that I’m passionate about, and not just choose things to pad my resume,” he says. “The judges are inventors themselves and, in some cases, they’ve had an impact on millions of people, so their input is important to me. I really took a lot away from the competition besides a bronze medal.”

The National Inventors Hall of Fame does outreach around the country. Blanchard says he hopes to get involved in future outreach projects in his hometown of El Paso, Texas. “It’s an amazing city,” he says, because it’s in the United States but is predominantly Hispanic. You encounter many different types of people and that helps drive adaptability and creativity. Unfortunately, it’s also geographically and culturally isolated so it’s harder for students to obtain exposure to scientific research. El Paso produces some great minds with great potential to make a difference in science, technology, engineering and math disciplines. I think it’s important to give kids there more exposure to STEM fields so they have an idea of the possibilities.”

Meanwhile, Blanchard and Yehl will continue developing the Rolosense with Salaita.

“We have this phenomenal technology that can make a difference in the world and we want to keep moving forward with it,” Blanchard says.

Emory's 'Rolosense' rolling to finals of Collegiate Inventors Competition
Nano-walkers take speedy leap forward with first rolling DNA motor

Thursday, November 3, 2016

The White House celebrates math and mentorship

By Carol Clark

“It’s not every day that the White House invites you to a reception in honor of what you do for a living,” said Emory mathematician Ken Ono.

He was a featured speaker at “Math and the Movies,” recently hosted by the White House Office of Science, Technology and Policy (OTSP) and the National Science Foundation (NSF).

The evening included a screening of the film “The Man Who Knew Infinity,” the true story of how the genius of an obscure Indian clerk, named Srinivasa Ramanujan, was discovered and nurtured by G. H. Hardy, a leading mathematician at Cambridge University. Their unusual collaboration changed the field of math and science forever.

Ono served as an associate producer and math advisor for the film, and afterwards helped found “The Spirit of Ramanujan Math Talent Initiative,” which aims to find exceptional mathematicians around the world and match them with advancement opportunities in the field.

France Cordova, director of the NSF, was among the speakers during the evening at the White House, which was focused on the importance of inspiring and mentoring students of science, technology, engineering and math (STEM).

Ken Ono (center), accompanied by U.S. chief Data Scientist D. J. Patil (left) and actor Jeremy Irons, presents a math problem to the nation while at the White House: What is the smallest number that is the sum of two cubes in two different ways? Click here for the answer.

“Tonight’s event addresses issues that we at NSF believe are critical for the nation,” Cordova said. “There is widespread recognition of the need to open up STEM opportunities for everyone. We’re looking for ways to broaden opportunities and include those who are underrepresented. That includes working with partners in museums, in social media and the entertainment industry to do a better job of telling the diverse stories of science and scientists.”

Hannah Larsen, a senior majoring in math at Harvard University, thanked the NSF for funding the Research Experience for Undergraduates program at Emory, where she spent three summers doing number theory research with Ono. The steadfast support of Ono and other mentors “deepened my love of mathematics,” Larson said, and was key to her decision to apply to graduate school and pursue a career in math research. Larsen recently won the Alice T. Schaefer Prize, given annually to the top undergraduate woman in math in the United States.

Following are highlights of remarks by other speakers.

Ken Ono: “Every few months you’ll hear about breakthroughs in black hole physics. Or solutions to ancient mathematical mysteries. Or even applications that help drive the Internet. I can tell you that the work of Ramanujan plays a role in all of those. If you want a role model for young students, if you want to help create world-class scientists, I think we should all do our part to make Ramanujan a household name.”

Andrea Hariston, applied research mathematician at the National Security Agency (NSA): “Exposure is a big, big deal for students who may not know what their options are. I had a mathematical curiosity growing up but I saw it as a hobby – solving puzzles – not as a career. A fellowship obligated me to do an internship at the NSA. That’s when I got mentors who opened up mathematics for me. They showed me you can do really interesting things with mathematics, really important things for the nation, using mathematics.”

D.J. Patil, chief data scientist for the OTSP: “People don’t always appreciate how much president Obama has done to return science to its rightful place, at the forefront of the nation, in leading and driving innovation. … What gets a kid excited about math? There are lots of different paths, but one of them is inspiration. I had really excellent coaches, people who were there to inspire, shape and mold me.”

Actor Jeremy Irons, who plays Hardy in the film: “Pure mathematics is rather similar to poetry and art. It’s something about which you can become passionate. It’s something that requires a mind that is really open and free to allow whatever to come to you. I thought, I know about that because that’s the state I try to get into when I’m acting.”

The beauty of math and Pi: Ken Ono chats with Neil deGrasse Tyson
Mathematicians find 'magic key' to drive Ramanujan's taxi-cab number

Sunday, October 30, 2016

Could you pass the scream test?

Halloween is a time to celebrate primal instincts, including our fascination with screams. Emory psychologist Harold Gouzoules, who researches how we perceive and interpret screams, says humans scream in five different contexts: Aggression, fear, pain, excitement and startle.

In the above CNN video, Gouzoules gives reporter Elizabeth Cohen an informal "scream test," to see if she can tell the difference.

The psychology of screams

Tuesday, October 25, 2016

BRAIN grant to fund study of how the mind learns

Biophysicist Ilya Nemenman, left, is developing theories about the brain that can be tested in the lab of biologist Sam Sober, right. (Emory Photo/Video).

By Carol Clark

How does the brain correct mistakes and guide the process of learning a skill? Why do some individuals learn faster than others?

Two Emory researchers – biophysicist Ilya Nemenman and biologist Sam Sober – recently received a $1 million grant from the National Institutes of Health BRAIN Initiative to explore these questions through a theoretical-experimental framework. Their research into how the sensory-motor loop controls and optimizes learning could lead to better protocols to help those dealing with major disruptions to their learned behaviors, such as when recovering from a stroke.

The BRAIN Initiative (Brain Research through Advancing Innovative Neurotechnologies) was launched by President Obama in 2014 as part of a widespread effort to gain fundamental insights for treating a range of brain disorders.

Emory has received other grants from the BRAIN Initiative: In 2015, a $1.7 million award went to neuroscientists Dieter Jaeger (Department of Biology) and Garrett Stanley (Emory-Georgia Tech’s Wallace H. Coulter Department of Biomedical Engineering). They will use the award to explore neural circuits related to sensing and physical action. In 2016, neurosurgeon Robert Gross in the School of Medicine received a $5 million grant to focus on optimizing neurostimulation therapies for epilepsy.

The grant received by Nemenman and Sober is part of a new cohort, opening another phase of the BRAIN Initiative: The development of theoretical, computational and statistical tools.

“Big data by itself is not useful,” Nemenman says. “We also need to come up with methods for understanding such data.”

Nemenman is working on a theory to help explain how the brain learns. “If you are learning something similar to something that you already know, it’s easier than if you are learning something entirely new,” he says. “We see this effect across the animal kingdom, including in humans. And this ability to learn something new changes with age.”

He gives the example that he will always speak English with an accent, since he is a native of Belarus and did not move to an English-speaking country until shortly before he became a student at Princeton. His children, however, will speak English without an accent since they were born in the United States and immersed in English from birth.

Nemenman is collaborating with Sober, who conducts experiments with Bengalese finches. “These songbirds are one of the best model systems available for studying how the brain learns to communicate,” Sober says.

The male songbirds sing to attract a mate, but they are not born with this ability, Sober explains. Instead, the young males learn to sing by memorizing, and then imitating, the singing of their fathers. When a young bird sings the wrong note, it tries to correct its mistake to match the memorized “target” sound.

In experiments, the Sober lab places tiny earphones on a songbird. When the bird sings, the researchers distort some of the notes slightly and play back the sound through the earphones. The bird is tricked into thinking it has sung a note incorrectly and tries to correct it.

Through this method, the lab has found that the birds are able to correct small distortions of sound, but they cannot correct large distortions.

“Many errors are distributed as a bell-shaped curve, but the distribution of singing errors in the birds is not bell-shaped,” Nemenman says. He is developing theories to explain how the difficulty of learning and correcting for large disturbances is related to this peculiar shape of the distribution of errors produced by the brain during learning.

“We can test the theories through experiments and learn more about the process,” he says. “The ultimate goal is to develop predictive models of how individuals learn from their errors that can be extended to other organisms, including humans.”

Nemenman also recently received a grant from the Kavli Foundation, to support workshops, symposiums and journal clubs that foster interdisciplinary theoretical and computational approaches to neuroscience, and bridge researchers at Emory and Georgia Tech.

It is important for physicists to share their expertise and collaborate with other scientists focused on understanding the brain, Nemenman says. As chair of the American Physical Society’s division of biological physics, he strives to establish programs that attract young physicists to neuroscience.

“Physicists are well posed to have a dramatic impact in this area,” he says. “We are trained to do science by combining theory and experiments. We can apply the same techniques to study the brain that we use to study other mysteries of the universe. Many graduate students in physics who came in intending to work on string theory, like I did, are coming out with a PhD focused on theoretical neuroscience.”

How songbirds learn to sing 
Biology may not be so complex after all

Thursday, October 20, 2016

The beauty of math and Pi: Ken Ono chats with Neil deGrasse Tyson on 'StarTalk'

StarTalk formula: What do you get when you add an astrophysicist and a number theorist to a comedian? A fun conversation when those variables are (from left) National Geographic Channel's Neil deGrasse Tyson, Emory mathematician Ken Ono and stand-up comic and writer Eugene Mirman.

“Math is one of the most feared subjects in school,” says astrophysicist Neil deGrasse Tyson, host of the National Geographic Channel’s “StarTalk,” to kick off an upcoming episode with Emory number theorist Ken Ono. “The phrase, ‘I was never good at math’ is probably uttered more than ‘I was never good’ at any other subject. What gives there?”

“Think of it this way,” Ono responds. “If you were an athlete, training for a marathon, you wouldn’t just expect to be fast at it. You’d have to practice. I think the reason people say they’re not good at math is because there’s this belief that if you’re good at math you’re just born with it. And that’s just so untrue.”

You can see a clip from the episode, to air Monday, November 7 at 11 pm, in the video below.

Ono and deGrasse, who are also joined by comedian Eugene Mirman, discuss everything from serial killers to the beauty in hidden patterns and how the Indian mathematician Srinivasa Ramanujan tamed Pi.

The episode, which is devoted to Ramanujan, will also feature actor Jeremy Irons. He will discuss his role as the mathematician G. H. Hardy, Ramanujan's mentor, in the film "The Man Who Knew Infinity." Ono served as an associate producer and the mathematical consultant for the film.

Ono and Irons will also be featured in a White House panel discussion as part of an event entitled "Math and the Movies" on Friday, October 28. You can watch the event live, starting at 5:30 pm, via this link.

Celebrating math, movies and a miracle

Wednesday, October 19, 2016

Emory biologist nurtures nature in his spare time

Biologist Chris Beck is one of three finalists for the 2016 Cox Conserves Heroes award, for his work with the Clyde Shepherd Nature Preserve. Emory Photo/Video.

By Kimber Williams
Emory Report

As a professor of pedagogy in Emory’s Department of Biology, Chris Beck is engaged in the scientific study of laboratory teaching, with a particular focus on how inquiry-based learning impacts students' science process skills and their understanding of the nature of science.

This month, however, Beck is being recognized for his work involving a very different laboratory.

Beck has been named as one of three finalists for the 2016 Cox Conserves Heroes award for his volunteer work at the Clyde Shepherd Nature Preserve (CSNP), a 28-acre wildlife sanctuary located along the floodplain of South Peachtree Creek in Decatur.

For more than a decade, Beck has volunteered at CSNP, coordinating hundreds of volunteers from both Emory and the wider community, leading fundraising efforts and managing capital improvement projects. Each finalist will be awarded $5,000 to be donated to a local environmental nonprofit of their choice. Beck has selected CSNP as his non-profit.

The final winner will be selected through an online public vote and will receive an additional $5,000 donation to their nonprofit. Voting runs through Oct. 26; final results will be announced mid-November.

Emory Report interviewed Beck to learn more about his efforts with the nature preserve.

Why is the preserve important?

From an ecological perspective, the preserve serves several purposes. It’s located on the floodplain of the south fork of Peachtree Creek, so it has a role in controlling storm water overflow and filtering the water that does flood out.

The preserve is also an important green space to a lot of wildlife, including over 150 to 160 species of birds, as well as amphibians, reptiles and a wide array of plants. It provides a great resource to both the local and broader Atlanta communities, in terms of offering a place to go and see wildlife and walk the trails.

It’s provided educational opportunities as well. Over the years, I’ve brought students from my ecology lab classes there and I know Georgia State University and Oglethorpe University use it, too. Emory has sent hundreds of volunteers there over the years. It’s provided a great way to engage the community.

Read the full interview with Beck in Emory Report.

Tuesday, October 4, 2016

Biology professor holds meetings on the run

Emory biology lecturer Patrick Cafferty (left, blue shorts and shirt) takes one of his weekly office hours on the road for a three-mile run through campus. Emory Photo/Video

By April Hunt
Emory Report

There’s a very good chance Patrick Cafferty runs a different meeting than you do.

The Emory University biology lecturer takes one of his weekly office hours on the road, heading out for a three-mile run through campus with students. It’s part of an overarching goal to truly connect with students in his human physiology class as a teacher and mentor.

“I invite every student to just come in and chat,” says Cafferty, decked out in running shorts and a tank top before one of the weekly runs. “Some are too shy to do it, but they can join a run and just listen, and we get to know each other on a personal level. There is an equalizing aspect of sport.”

Early in the semester, Cafferty is the one doing most of the talking. Part of that is his 10-minute mile pace — slow for a serious triathlete like him but a challenge for some students. But it also lets Cafferty discuss class topics, such as the neurobiology behind cramped muscles or the dilatation of blood vessels serving muscles during exercise, as they are happening to some of the runners.

“This is great for me, because it’s an outlet to exercise, study and develop a relationship with faculty and students all at once,” says Amancio Romero, a junior behavioral biology and neuroscience major who last ran regularly, as a sprinter, in high school.

Call it active learning, something Cafferty has experienced personally. He grew up in Canada, interested first in exploring wildlife and later, studying life from the molecular level. At the same time he grew to understand complex cellular behavior from a biology perspective, he was applying those lessons to his training in Iron Man competitions and cycling. But it was not until graduate school at McGill University in Montreal, when he joined a swim club that welcomed students, staff and faculty, that he realized the value of linking those two worlds.

At McGill, Cafferty ended up in the pool with some professors he never would have otherwise met. He also connected with a professor who ended up being a doctoral mentor.

“There is a reason we have business meetings at lunch or over golf. It’s about being comfortable and being able to have natural conversations,” Cafferty says.

Those realizations prompted Cafferty to launch a run club when he came to Emory as a faculty-in-residence in 2011. Students, faculty and community members participated in that club, which became the model for what he calls his Active Office Hours.

Students who have participated so far include an Emory swimmer who gave up the sport to make time for studying, students who last ran during high school track or cross country, and even one person who had never run before.

One of the students has joined while listening to Cafferty’s lectures on an MP3 device, asking questions as they arise in his headphones.

Another, senior Maiya Smith, came with a screenshot of questions to ask Cafferty during the run through Lullwater Preserve.

“I never heard of a professor doing this before, and I love it,” says Smith, an anthropology and human biology major who ran marathons in high school. “I can see our runs directly connecting to class, and that just makes me want to ask even more questions.”

Like typical desk-bound office hours, the active versions are also a valuable resource for students beyond the classroom.

Cafferty welcomes students outside his class to the runs. He also plans on interval training runs, which will help some runners improve their times while letting everyone regroup to chat.

Conversations vary from campus gossip to current TV shows to classroom lessons, he says. Inevitably, questions come up about fitness or diet trends, issues directly linked to classroom work on nutrition and exercise.

“Running is completely new to me,” says Luke Roberts, a junior biology major who spent a year on Emory’s swim team. “I don’t have any breath left to ask questions, but it’s interesting just to listen and put it all together.”

The benefits spill over to students who don’t want to run, too. More of those students appear to have noticed Cafferty’s passion for biology in general and physiology in particular, and they are showing up more often in his Rollins Research Center office to talk.

“I hope to share something I’m kind of good at and enjoy with them, because I want them to know me,” Cafferty says. “And I think students see if you have a genuine interest in getting to know them.”

Friday, September 30, 2016

Emory's 'Rolosense' rolling to finals of Collegiate Inventors Competition

“I think the advantage we have with our technology is that it's so simple," says Aaron Blanchard, left (a PhD student in Emory's Laney Graduate School and Coulter Department of Biomedical Engineering at Georgia Tech and Emory), shown using the Rolosense with his advisor, Emory chemist Khalid Salaita. 

By Carol Clark

The first rolling DNA motor – the biological equivalent of the invention of the wheel for the field of DNA machines – is headed from its origins in an Emory University chemistry lab to the finals of the 2016 Collegiate Inventors Competition in Washington D.C.

Kevin Yehl and Aaron Blanchard make up one of six teams of graduate students who will be flown to the finals in early November. Yehl and Blanchard developed the DNA motor (dubbed Rolosense), and its application as a chemical sensor, in the laboratory of their advisor – Emory chemist Khalid Salaita.

Blanchard is a PhD student in Emory's Laney Graduate School and the Coulter Department of Biomedical Engineering (BME) at Georgia Tech and Emory, while Yehl recently graduated from Emory with a PhD in chemistry.

The entries of the elite student teams represent the most promising inventions from U.S. universities. “Their ideas will shape the future,” wrote Michael Oister, CEO of the National Inventors Hall of Fame, in a letter announcing the finalists.

The Collegiate Inventors Competition annually gives out about $100,000 in cash prizes and is considered the foremost program in the country encouraging invention and creativity in undergraduate and graduate students. The competition also promotes entrepreneurship, by rewarding ideas that hold value for society.

The Rolosense is 1,000 times faster than any other synthetic DNA motor. Its speed means a simple iPhone microscope can capture its movement through video, giving it potential for real-world applications, such as disease diagnostics.

Kevin Yehl sets up a smart-phone microscope to get a readout for the particle motion of the rolling DNA-based motor.

"It's exciting," Yehl says. "Previous winners have gone on to start companies with their inventions and become successful scientists. It will be great to get feedback from the judges on the Rolosense."

The judges will include inductees to the National Inventors Hall of Fame, officials from the U.S. Patent and Trademark Office, and scientists from the global healthcare firm AbbVie.

Some of the best discoveries involve serendipity, and that was the case for the Rolosense. Yehl was working last year as a post-doctoral fellow in the Salaita lab, which specializes in visualizing and measuring mechanical forces at the nano-scale. He was conducting experiments using enzymatic nano-particles – micron-sized glass spheres. “We were originally just interested in understanding the properties of enzymes when they’re confined to a surface,” Yehl says.

During the experiments, however, he learned by accident that the nano-particles roll. That gave him the idea of constructing a rolling DNA-based motor using the glass spheres.

The field of synthetic DNA-based motors, also known as nano-walkers, is about 15 years old. Researchers are striving to duplicate the action of nature’s nano-walkers. Myosin, for example, are tiny biological mechanisms that “walk” on filaments to carry nutrients throughout the human body. 

So far, however, mankind’s efforts have fallen far short of nature’s myosin, which speeds effortlessly about its biological errands. Some synthetic nano-walkers move on two legs. They are essentially enzymes made of DNA, powered by the fuel RNA. These nano-walkers tend to be extremely unstable, due to the high levels of Brownian motion at the nano-scale. Other versions with four, and even six, legs have proved more stable, but much slower. In fact, their pace is glacial: A four-legged DNA-based motor would need about 20 years to move one centimeter.

 A cell phone app is in the works.
The Rolosense design mows over these limitations. Hundreds of DNA strands, or “legs,” are allowed to bind to the sphere. These DNA legs are placed on a glass slide coated with the reactant: RNA.

The DNA legs are drawn to the RNA, but as soon as they set foot on it they destroy it through the activity of an enzyme called RNase H. As the legs bind and then release from the substrate, they guide the sphere along, allowing more of the DNA legs to keep binding and pulling.

“The Rolosense can travel one centimeter in seven days, instead of 20 years, making it 1,000 times faster than other synthetic DNA motors,” Salaita says. “In fact, nature’s myosin motors are only 10 times faster than the Rolosense, and it took them billions of years to evolve.”

The researchers next demonstrated the Rolosense could be used to detect a single DNA mutation by measuring particle displacement. Yehl simply glued lenses from two inexpensive laser pointers to the camera of an iPhone to turn the phone’s camera into a microscope and capture videos of the particle motion.

The simple, low-tech method could come in handy for doing diagnostic sensing in the field, or anywhere with limited resources.

Nature Nanotechnology published the work on the rolling DNA motor. The researchers have filed an invention disclosure patent for the concept of using the particle motion of the Rolosense as a sensor for everything from a single DNA mutation in a biological sample to heavy metals in water.

Yehl has since left Emory for a position at MIT, but he continues to work with Salaita and Blanchard on refining the Rolosense.

Blanchard, who has a background in computer coding, is integrating the data analysis of the Rolosense into a smart phone app that will provide a readout of the results.

“I feel really fortunate as a graduate student to be working on this project,” Blanchard says. “As the molecular detection field grows, I think that Rolosense will grow with it.”

For their demonstration during the finals, Yehl and Blanchard plan to hand the judges smart phones and samples of water (including some containing lead), and let the judges use Rolosense to test the samples.

“It can be easy to dazzle with complex technologies like a robot,” Blanchard says, “but I think the advantage that we have with our technology is that it’s so simple. We can let the judges see for themselves how they can use Rolosense to quickly learn something useful, like whether a water source is contaminated with a heavy metal.”

Nano-walkers take speedy leap forward with first rolling DNA motor
Chemists reveal the force within you
Molecular beacons shine light on how cells crawl

Wednesday, September 28, 2016

Psychologists create 'listicle' of unlikely study authors

Long before he became famous for landing a plane on the Hudson River, Chesley Sullenberger III published a scientific paper on humor and vision. Image shows a detail from the new movie "Sully."

Benedict Carey writes in The New York Times about how Emory psychologist Scott Lilienfeld and a colleague created a "listicle" of psychology studies by unlikely authors. Below is an excerpt:

"The study was almost laughably arcane: Air Force cadets’ pupils tended to dilate more when they read cartoons they thought were funny than for ones they didn’t think were funny.

"But the real punch line of this 1978 experiment — 'Pupillary size as an indicator of preference in humor,' published in the journal Perceptual and Motor Skills — is what became of one of the authors, listed as Sullenberger, C. B.

"Chesley B. Sullenberger III is the retired airline captain who safely landed US Airways Flight 1549 in the Hudson River in 2009 and the hero of the new Clint Eastwood-directed movie 'Sully.' By virtue of publishing his small experiment, he is also a member of an unusual club. Call it the you’ll-never-guess-who-wrote-that collection of authors of psychology studies."

Read the whole article in The New York Times.

Wednesday, September 21, 2016

Status drives men's reproductive success across non-industrial world

The reproductive benefits of status reached their peak in pre-modern empires. A genetic study, for instance, found that 8 percent of men in populations spanning Asia shared nearly identical Y-chromosome sequences with Mongolian ruler Genghis Khan (shown entering the city of Beijing).

By Carol Clark

The reproductive success of men in non-industrialized societies is closely tied to their social status, finds a new meta-analysis published in the Proceedings of the National Academy of Sciences.

The analysis looked at studies of 33 non-industrial societies from around the globe, including hunter-gatherers, nomadic pastoralists and agriculturalists.

“We were surprised to learn that the correlation held up for a range of societies and their different measures for status,” says Adrian Jaeggi, an anthropologist at Emory University focused on primate and human behavioral ecology. “It doesn’t matter whether a man is a better hunter, owns more land or more livestock – men with high social status had more children compared to men with low status.”

Jaeggi co-authored the study with Christopher von Rueden, an anthropologist specialized in leadership studies at the University of Richmond in Richmond, Virginia.

Their findings go against the egalitarian hypothesis, the idea that status was a relatively weak target of selection for modern humans, since most of that evolutionary period involved living as egalitarian hunter-gatherers.

The !Kung bushmen of the Kalahari serve as a classic example of the egalitarianism associated with hunter-gatherer societies. “They are not allowed to brag about their hunting success, it’s not culturally acceptable,” Jaeggi says. “When one of them kills a large animal, he comes back to camp and sits down quietly by the fire and he is modest about it. Their society is built on mutual help. Sometimes a hunter may only be successful one out of every 10 days. But if they all support each other and share their game, on average they eat every day.”

Bushmen in Botswana demonstrate how to start a fire by rubbing sticks together. Such hunter-gatherer societies do not amass material wealth and are built on mutual help and support. Photo by Ian Sewell.

The egalitarian hypothesis posits that it was not until humans shifted from primarily hunter-gatherer societies toward pastoralism, agriculture and industrialization that status became a key driver for male reproductive success. “Once you start acquiring property and other forms of material wealth, you have assets to transmit to your offspring, so you would expect to see status more closely tied to reproductive success,” Jaeggi explains.

In humans, these reproductive benefits of status reached their peak in pre-modern states and empires that enabled powerful rulers to have access to large numbers of women. A genetic study, for instance, found that 8 percent of men in populations spanning Asia shared nearly identical Y-chromosome sequences with Genghis Khan, the Mongolian ruler who died in 1227.

The current meta-analysis suggests that status-seeking was not just a consequence of more formal social hierarchies and the rise of greater inequalities, but an evolved trait.

While a good hunter may not have material wealth, he carries “embodied capital,” measured by qualities like intelligence, skill, good health and reliable social connections, Jaeggi explains.

“Hunter-gatherer societies may actively work towards leveling any hierarchy, but at the same time people are aware of which men are better hunters and that appears to give them a reproductive edge,” he says. “And the relationship between status and reproductive success is as strong for a hunter as it is for a farmer or pastoralist. That indicates a biological basis for striving for status: It’s universally rewarded with the only currency that matters in biology – children.”

Wealthy men across most of the modern, industrialized world, however, tend to have fewer children than poor men. The link between male status and reproductive success is broken, due to women’s rights and access to contraception.

“Women can be more independent and successful in modern society,” Jaeggi says. “They get to decide if they want to continue to reward status-seeking in men by allowing them to have more children. Or whether they want to reward men who are more compliant with what women want.”

Conspicuous consumption may drive fertility down

Thursday, September 15, 2016

Sensory connections spill over in synesthesia

One of the most common forms of synesthesia is when people involuntarily see particular colors in connection with letters, numbers or sounds.

By Quinn Eastman
Woodruff Health Sciences Center

Neuroscientists at Emory University have found that people who experience a mixing of the senses, known as synesthesia, are more sensitive to associations everyone has between the sounds of words and visual shapes. The results are published in the European Journal of Neuroscience.

Synesthesia is a stable trait, and estimated to be present in 1 to 4 percent of people. It can be inherited, although the precise genes have not been identified. One of the most common forms of synesthesia is when people involuntarily see particular colors in connection with letters, numbers or sounds.

Many artists and composers have described their experiences with synesthesia. Children with synesthesia say sometimes that it is distracting when they are trying to read. Thus, understanding the origins of synesthesia may help people with dyslexia or other learning differences, or people who have lost their sight or hearing and are trying to engage in sensory substitution for rehabilitation.

Researchers led by neurologist Krish Sathian recruited 17 people with synesthesia, and asked them to take a form of the IAT (implicit association test). Known for its use probing social attitudes such as racial prejudice, the IAT can also assess "cross-modal correspondences."

An example of a cross-modal correspondence is that we describe musical notes as being "high" or "low" – words that also signify relative positions in space. Another is that we think of some sounds such as "m" and "l" as soft, and are more likely to associate them with rounded shapes. Similarly, we connect hard sounds such as "k" and "t" with angular shapes.

"There's been a debate about synesthesia," Sathian says. "Are the associations synesthetes have just extreme versions of cross-modal correspondences that other people have, or are they qualitatively different?"

Sathian and his colleagues found that people with synesthesia were more sensitive to correspondences between the sounds of pseudowords -- words without meaning in English -- and rounded or angular shapes.

"It shows that something about their synesthesia is spilling over into another domain," he says. "But that spillover is limited to a correspondence that is post-perceptual and symbolic – it's not purely sensory."

Such correspondences are called "sound-symbolic," and may be relevant to the evolutionary origins of language, Sathian adds.

People with synesthesia were not significantly more sensitive to purely sensory associations between the pitch of a sound and the size or position of a shape, compared to non-synesthetes. In this situation, sensitivity on the IAT means that study participants would have a greater difference in response times to congruent pairings of shape and sound (a high position in space, and a high pitch, for example) in comparison to incongruent pairings.

Participants in the study were recruited through advertisements on the Emory campus and screened with an online test called the Synesthesia Battery. This test confirms whether people who report they have synesthesia have consistent associations.

A connection between letters or other symbols and colors, also known as "grapheme-color" synesthesia, was the most common type in the Emory study. It may represent the presence of idiosyncratic wrinkles in how people learned their letters or other symbols during childhood. Indeed, Sathian notes that one study suggests that a popular brand of refrigerator magnets had an influence on what letter-color associations people with this form of synesthesia developed.

To be sure, people with synesthesia are not all the same, says senior research associate Simon Lacey, the first author of the paper. Some describe experiencing connections between shapes and tastes, or porous boundaries between self and non-self (so-called "mirror touch")."

Brain imaging studies have shown that people with synesthesia tend to be wired differently: they display hyperconnectivity between parts of their brains related to their synesthetic experiences. Scientists have proposed that synesthesia represents alterations in pruning, the process of editing connections between brain cells.

Sathian is professor of neurology, rehabilitation medicine and psychology at Emory University and executive director of the Rehabilitation R&D Center for Visual and Neurocognitive Rehabilitation at the Atlanta Veterans Affairs Medical Center. Sathian and collaborator Lynne Nygaard, professor of psychology, are exploring the neural bases of cross-modal correspondences and of synesthesia using brain imaging studies.

Uncovering secrets of sound symbolism

Wednesday, September 7, 2016

Set phasers to stun: Star Trek turns 50

Star Trek blasted audiences with important social messages and fired up enthusiasm for space exploration and science. Among the iconic characters in the series are, from left: Spock (Leonard Nimoy), Captain Kirk (William Shatner) and Montgomery “Scotty” Scott (James Doohan). 

Sidney Perkowitz, Emory emeritus professor of physics, wrote an article for Nature about the impacts of Star Trek on science, technology and society as the science fiction series turns 50. Below is an excerpt:

“Half a century ago, in September 1966, the first episode of Star Trek aired on the US television network NBC. NASA was still three years short of landing people on the Moon, yet the innovative series was soon zipping viewers light years beyond the Solar System every week. After a few hiccups it gained cult status, along with the inimitable crew of the starship USS Enterprise, led by Captain James T. Kirk (William Shatner). It went into syndication and spawned 6 television series up to 2005; there are now also 13 feature films, with Star Trek Beyond debuting in July this year.

“Part of Star Trek's enduring magic is its winning mix of twenty-third-century technology and the recognizable diversity and complexity enshrined in the beings — human and otherwise — created by the show's originator Gene Roddenberry and his writers. As Roddenberry put it, ‘We stress humanity.’ The series wore its ethics on its sleeve at a time when the Vietnam War was raging and anti-war protests were proliferating, along with racial tensions that culminated in major US urban riots in 1967–68.”

Read the whole article in Nature.

Fantastic light: From science fiction to fact

Tuesday, September 6, 2016

Pistil-packing science: Pollen genetics could help fight crime

A European honey bee collects nectar, gathering pollen on its body in the process. Emory biologists Karen Bell and Berry Brosi, who study pollen to monitor the health of ecosystems, say that pollen analysis also holds potential to help with forensic investigations.

By Karen Bell, Berry Brosi and Kevin Burgess

Bell is a post-doctoral fellow in the lab of Brosi, an evolutionary biologist in Emory's Department of Environmental Sciences, focused on the study of bees. Burgess is a biologist at Columbia State University. This article originally ran in The Conversation.

Imagine you're a detective working on a murder case. You have a body, but you believe it was moved from another location. Now what? There's one unexpected tool you might use to follow up on this suspicion: forensic palynology. That's the application of palynology – the study of pollen – to crime investigation.

But how does pollen have any bearing on forensics? While usually unseen, pollen is essentially ubiquitous in terrestrial habitats, and it is extremely tough. In fact, pollen is so durable that paleontologists can examine fossilized pollen grains in ancient sediments to see what plants grew during prehistoric times. And the “signature” of which pollen grains are present is specific to a particular place (because different plant species occur in different areas) and time (because different plant species flower at different times).

All of that makes pollen an ideal biomarker for linking people and objects to particular places and times, a central need in forensic investigations. Despite this potential utility, forensic palynology has been underutilized, because of its reliance on specialized experts to meticulously identify pollen visually under the microscope.

But recently researchers developed a new technique for identifying pollen, using genetics. By making identification much easier and faster for large numbers of pollen samples, this development has the potential to transform forensic palynology, allowing us to harness the power of pollen to solve crimes.

"Pollen could be a great biomarker to work out where people have been, or where something they were carrying has been," says Emory biologist Karen Bell, shown in the field.

Forensic palynology has been particularly useful in cases where there is suspected movement of evidence, or where a crime has occurred in a location with distinct plant species. For example, following the Bosnian war, investigators uncovered mass graves where bodies had been moved from different locations. Pollen was one of the lines of evidence used to trace bodies to their original burial sites. In a case in New Zealand, a burglar was tracked to the scene of the crime when pollen grains on his clothing were matched to an uncommon plant species growing in front of the victim’s house.

There are many other types of cases where forensic palynology could be applied. Objects under examination in missing person cases could be traced to their origin. Analysts could tie individual criminals' travel histories together based on finding a similar pollen species composition on seized evidence, possibly linking their crimes and providing direction for further investigation. Officials could determine illegal imports' country of origin.

Traditionally, forensic palynology is done by examining pollen grains under a microscope and comparing them to known pollen morphology. This is a highly specialized skill, and there are few experts able to identify plant species based on the size, shape and color of the pollen grains. After all, researchers estimate almost 400,000 species of plants live on our planet today. There is currently only one person employed full-time as a forensic palynologist in the U.S.

Forensic palynology is further limited by the labor intensiveness of morphological identification. Frequently it's impossible to determine the exact species present; identification is typically to a genus or family of plants – a group of species, in other words. This limits the technique's utility, because while many plant species occur in a small geographic range, the genus or family in which they belong may cover a much broader area.

"Because pollinator species are declining so rapidly, we need high through-put methods of analyses," Bell says, noting that those same techniques may make pollen genetics practical for other uses.

In a recently published article in Forensic Science International Genetics, we revealed how identifying pollen through DNA barcoding, on its own or with traditional palynology, could be a practical alternative.

DNA barcoding is a way to identify species via their species-specific genetic signatures. To do this for pollen, scientists sequence the DNA from a genetic region known to occur in all plants, but which varies from species to species. There are two parts to the standardized sequence we use for plant DNA barcoding. One is a section of the large subunit of a gene called ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcL for short). The other is a gene called maturase-K (matK). These genes are both essential for a plant to survive, and are thus present in all plants. Once an investigator sequences these gene regions from a sample, they can be compared to a database containing all the known DNA sequences of rbcL and matK to identify the species.

To DNA barcode pollen, the first step is to extract the DNA. Pollen grains produce the male reproductive cells (sperm) of the plant. Each pollen grain has a tough outer layer called the exine, made of a protein called sporopollenin. We need to break the exine in order to release the DNA that's protected inside. We do this by putting the pollen grains in a tube filled with small silica beads and shaking vigorously for several minutes. Once the cells release their DNA, it can be purified and then sequenced.

High-throughput DNA sequencing is a methodological advance that has made pollen DNA barcoding feasible. This new method allows researchers to sequence multiple pieces of DNA at the same time, without separating them first. It's a key innovation because forensic pollen samples typically contain a mixture of species. Without high-throughput sequencing, these species would first need to be painstakingly separated – and then we'd be back to the same efficiency problems of traditional morphological analysis. With high-throughput sequencing, the whole mixture of pollen grains can be ground up in one sample, the DNA isolated and sequenced, and matched to a database. This technique is known as DNA metabarcoding.

Although pollen DNA barcoding has not yet been applied to forensic palynology, similar techniques have been used to quality test honey, determining the plant species on which bees have been foraging. Pollen DNA barcoding has also contributed to air quality monitoring, when it's useful to know what allergens are present in the environment.

Optimizing these methods for forensics may require some small modifications, such as dealing with very few pollen grains in a sample. Ideally a standardized method should be developed for forensics, to enable comparisons between different cases, studied by different scientists. It will also be necessary to expand the reference databases, to include more species that might be of interest to forensics specialists.

But while there are still a few hurdles to overcome, eventually pollen DNA barcoding could become a common and scientifically rigorous technique in law enforcement and national security.

Pollinators vital to food supply facing extinction, U.N. report warns
Bees 'betray' their flowers when pollinator species decline The Conversation