Monday, October 31, 2011

Chemists reveal the force within you

By Carol Clark

A new method for visualizing mechanical forces on the surface of a cell, reported in Nature Methods, provides the first detailed view of those forces, as they occur in real-time.

“Now we’re able to measure something that’s never been measured before: The force that one molecule applies to another molecule across the entire surface of a living cell, and as this cell moves and goes about its normal processes,” says Khalid Salaita, assistant professor of biomolecular chemistry at Emory University. “And we can visualize these forces in a time-lapsed movie.”

Salaita developed the florescent-sensor technique with chemistry graduate students Daniel Stabley and Carol Jurchenko, and undergraduate senior Stephen Marshall.

“Cells are constantly tugging and pushing on their surroundings, and they can even communicate with one another using mechanics,” Salaita says. “One way that cells use forces is evident from the characteristic architecture of tissue, like a lung or a heart. If we want to really understand cells and how they work, we have to understand cell mechanics at a molecular level. The first step is to measure the tension applied to specific receptors on the cell surface.”

The researchers demonstrated their technique on the epidermal growth factor receptor (EGFR), one of the most studied cellular signaling pathways. They mapped the mechanical strain exerted by EGFR during the early stages of endocytosis, when the protein receptor of a cell takes in a ligand, or binding molecule. The results showed that the cell does not passively absorb the ligand, but physically pulls it inside during the process. Their experiments provide the first direct evidence that force is exerted during endocytosis.

"Once a force is applied to the polymer, it stretches out,” Salaita explains. “And as it extends, the distance from the quencher increases and the fluorescent signal turns on and grows brighter." Graphic by Daniel Stabley.

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.

“It’s known that if EGFR is over-active, that can lead to cancer,” Salaita says. “And one of the ways that EGFR is activated is by binding its ligand and taking it in. So if we can understand how tugging on EGFR force changes the pathway, and whether it plays a role in cancer, it might be possible to design drugs that target this pulling process.”

Several methods have been developed in recent years to try to study the mechanics of cellular forces, but they have major limitations.

One genetic engineering approach requires splitting open and modifying proteins of a cell. This invasive technique may change the behavior of the cell, skewing the results.

The new technique for visualizing cellular forces uses a standard fluorescence microscope.

The technique developed at Emory is non-invasive, does not modify the cell, and can be done with a standard fluorescence microscope. A flexible polymer is chemically modified at both ends. One end gets a fluorescence-based turn-on sensor that will bind to a receptor on the cell surface. The other end is chemically anchored to a microscope slide and a molecule that quenches fluorescence.

“Once a force is applied to the polymer, it stretches out,” Salaita explains. “And as it extends, the distance from the quencher increases and the fluorescent signal turns on and grows brighter. We can determine the force being exerted by measuring the amount of fluorescent light emitted.”

The forces of any individual protein or molecule on the cell surface can be measured using the technique, at far higher spatial and temporal resolutions than was previously possible.

Many mysteries beyond the biology and chemistry of cells may be explained through measuring cellular forces. How does a cancer cell crawl when a tumor spreads? What are the forces involved in cell division and immune response? What are the mechanics that allow groups of cardiac cells to beat in unison?

“Our method can be applied to nearly any receptor, opening the door to rapidly studying chemical and mechanical interactions across the thousands of membrane-bound receptors on the surface of virtually any cell type,” Salaita says. “We hope that measuring cellular forces could then become part of the standard repertoire of biochemical techniques that scientists use to study living systems.”

Undersea cables add twist to DNA research
Biochemical cell signals quantified for first time

Thursday, October 27, 2011

The spirit of Emory came from a lab

From Emory Magazine:

Does any other university have a biology lab skeleton as its mascot? We think it unlikely. As mascots go, Emory’s is on the eccentric side. Dooley made his first appearance in 1899 in the “Phoenix,” Emory’s literary journal at the time, with an essay titled “Reflections of the Skeleton.” Writing as a specimen from the Science Room, Dooley was a mournful character, complaining about the high spirits of the “college boys” who disturbed his rest.

He showed up again a decade later and remained a kind of campus commentator, but his physical presence was not observed until 1941, when the Board of Trustees first allowed dancing on campus. That seems to have cheered him up.

Now known as James W. Dooley (he takes his first name and middle initial from the current university president), Dooley is represented on campus by a student – whose identity is kept secret – dressed as a skeleton in a black cape, a black top hat, and white gloves.

He has become a Lord of Misrule, the instigator of the festive Dooley’s Week – traditionally ushered in by the skeleton himself – who has arrived by helicopter, motorcycle and vintage car, accompanied by his entourage of student bodyguards.

Dooley is part of the rich history that Emory is celebrating during its 175th anniversary year, including many major science milestones. During the past 10 years alone, Emory researchers have made 1,418 invention disclosures and applied for 968 patents. The university has seen 32 products reach the market and launched 55 start-up companies. Read more in Emory Magazine.

Wednesday, October 26, 2011

Are we turning Steve Jobs into a saint?

Is that a MacBook Air Steve Jobs is presenting to the masses, or a bible for the cult of mass celebrity? (Photo credits, above and below:

Gary Laderman, chair of religion at Emory, writes on CNN's Belief Blog:

Steve Jobs has been the object of numerous memorials, and tributes - more than a million - are being posted on Apple’s “Remembering Steve” webpage, with condolences as well as testimonials about how Jobs and his products have touched and indeed transformed the lives of countless individuals.

Make no mistake about it, the veneration we are seeing in the aftermath of Jobs’ death is religious through and through - not “kinda” religious, or “pseudo” religious,” or “mistakenly” religious, but a genuine expression for many of heartfelt sacred sentiments of loss and glorification.

It is not tied to any institution like a church or to any discrete tradition like Buddhism; it is, instead, tied to a religious culture that will only grow in significance and influence in the years ahead: the cult of celebrity.

As more and more people move away from conventional religions and identify as “nones” (those who choose to claim “no religion” in polls and surveys), celebrity worship and other cultural forms of sacred commitment and meaning will assume an even greater market share of the spiritual marketplace.

In life Jobs may have been something of an enigma who maintained his privacy and generally stayed out of the public limelight. In death, Jobs now is an immortal celebrity whose life story, incredible wealth, familiar visage, and igadgets will serve as touchstones for many searching for meaningful gods and modes of transcendence.

It has been said that death is the great equalizer - rich and poor, successes and failures, the powerful and the disempowered cannot escape the one inevitable fact of human existence.

Jobs and other celebrities cannot escape this reality, but unlike you and me, they live on in the memories of fans and followers and become guiding lights in the mundane darkness of our ordinary lives.

Read more on the CNN Belief Blog.

Dining with machines that feel
Steve Jobs inspires prize-winning short film

Tuesday, October 25, 2011

Dalai Lama leads talks on ecology and ethics

“The slow meltdown of Earth’s capacity to sustain much of life, as we know it, poses an urgent challenge for both spiritual traditions and science.”

That’s the introductory statement to the conference on Ecology, Ethics and Interdependence, held Oct. 17-21 in Dharamsala, India. The Dalai Lama, Presidential Distinguished Professor at Emory, led the meeting, hosted by the Mind and Life Institute.

Emory religion scholar John Dunne moderated a session called “A Role for Theology," which is summed up on the conference web site:

“If our world view is one based on contemporary science as well as the deepest wisdom of many religions, a world view that claims we are radically interrelated and interdependent with all other forms of life, then we will, or should, respond to our present crisis with similarly radical changes in our thinking and behavior. But do we? This is the critical question for all fields of concern with climate change, including the religions – and it is a very difficult one. What causes people to change at a deep enough level so their behavior changes as well? The shock of climate change may be the catalyst to awaken us from the lie of the current world view of individual fulfillment through consumerism, to the reality of fulfillment by sharing with needy fellow creatures and the Earth itself, through religious understandings of limitation, detachment and self-emptying.”

The video of the session is above. Here's a link to videos of all the sessions of the conference.

Monks + scientists = new body of thought

Sunday, October 23, 2011

Happy Mole Day!

If you have to ask, chances are you are not celebrating Mole Day, an unofficial holiday for chemists, on October 23, between 6:02 AM and 6:02 PM. The time and date are based on Avogadro's number, which defines the number of particles in one mole of substance. Emory chemists celebrate in a big way. Their tradition involves a pinata, this year hand-crafted into an actual garden-variety mole by Charlene Chan and Yoshie Narui, and some initiation rites for new faculty members (see Chris Scarborough in action in the video below). Cheers to Avogadro, and to scientists everywhere today.

Friday, October 21, 2011

Norovirus stays infective for months in water

Transmission electron micrograph of Norovirus particles in feces. (Graham Colm, Wikipedia Commons.)

From Science Daily:

Researchers from Emory University have discovered that norovirus in groundwater can remain infectious for at least 61 days. The research is published in the October Applied and Environmental Microbiology.

Human norovirus is the most common cause of acute gastroenteritis.The disease it causes tends to be one of the more unpleasant of those that leave healthy people unscathed in the long run, with diarrhea and vomiting that typically last for 48 hours. Norovirus sickens one in 15 Americans annually, causing 70,000 hospitalizations, and more than 500 deaths annually, according to the Centers for Disease Control and Prevention.

The results answer a question of great importance to public health, which had driven researcher Christine Moe and her colleagues to conduct this research: If well water becomes contaminated with noroviruses--perhaps from leaking sewer lines or a septic tank -- how long do these noroviruses survive in water, and when would it be safe to drink from that well?

Read the full article in Science Daily.

A few things you may not know about water
Sewage raises West Nile virus risk

Thursday, October 20, 2011

Chemists modify rules for reaction rates

By Carol Clark

Theoretical chemists at Emory University have solved an important mystery about the rates of chemical reactions and the so-called Polanyi rules.

The findings, published in the journal Science, reveal why a reaction involving methane does not conform to the known rules, a problem that has baffled physical chemists in recent years.

“We showed that a pre-reactive, long-range force can align the reaction of a chorine atom with methane, or natural gas, in a way that actually inhibits the reaction,” says Joel Bowman, a professor of theoretical chemistry at Emory and the Cherry L. Emerson Center for Computational Chemistry. “We believe that the theoretical work that we did has extended and modified the Polanyi rules.”

Bowman published the results with Gabor Czako, a post-doctoral fellow in theoretical chemistry who performed most of the complex computational and mathematical analyses that uncovered the results.

Long-range, their findings could play a role in the development of cleaner, more efficient fuels.

The reactive properties of methane are of particular interest, since it is an important fuel. Photo by Carol Clark.

Understanding the dynamics of chemical reactions is key to driving reactions efficiently, whether in a laboratory experiment or in an industrial application. In 1986, John Polanyi shared the Nobel Prize in chemistry, in part by providing general rules for how different forms of energy affect the rates of reactions.

“The Polanyi rules tell you the best way to deposit energy in a simple molecule to make a chemical reaction occur,” Bowman says. “It’s a bit like knowing in advance how to invest $1,000 to maximize the return on investment.”

Polanyi developed the framework based on studies of simple reactions of chlorine and fluorine atoms with hydrogen gas. As technology has advanced in recent years, some chemists began testing the Polanyi rules for more complicated reactions, and the rules appeared to break down. Most notably, sophisticated molecular beam experiments by Kopin Liu at the Institute of Atomic and Molecular Sciences in Taiwan showed that the reaction of halogen atoms with methane did not conform to the rules.

“Suddenly, the rules appeared to have changed, and no one could explain why,” Bowman says. “We decided to roll up our sleeves and attack the problem theoretically.”

Bowman and Czako drew from the computational power of the Emerson Center, specialized software and analytical techniques. They first created theoretical-computational simulations of the experiments done by Liu and others, and then described the results mathematically.

“Our calculations showed essentially an exact agreement with the experimental results,” Bowman says. “When theory and experiment agree you’re happy, but you still want to know why.”

Determining why the reactions did not conform to the Polanyi rules was another complicated task, involving quantum mechanics and forces that govern the reaction down to the atomic level.

“As theoreticians, we’re able to zoom in and look at the results of our calculations in a way that’s virtually impossible in an experiment,” Bowman says.

They identified a subtle interplay between the Polanyi rules and a pre-reactive long-range force of methane with chlorine. If you follow the Polanyi rules, this long-range force, or steric control, will misalign the reactants, preventing them from docking correctly and inhibiting a reaction. But if you apportion the energy in the opposite way to the rules, the misalignment is wiped out and the reaction occurs.

“This long-range force was playing a bigger role than was previously realized,” Bowman says. “It can actually trump the Polanyi rules, at least in the reactions that Liu and we looked at. The Polanyi rules are certainly not all wrong, they just appear to be too simple to apply to more complex reactions.”

The research was funded by the National Science Foundation and the U.S. Department of Energy.

The reactive properties of natural gas are of particular interest since it is an important fuel. Bowman and Czako are now applying their techniques to study the combustion of methane and oxygen, which produces carbon dioxide. “It’s important to understand the dynamics of this reaction, because it might lead to more efficient ways to produce fuel, and a reduction in the levels of pollution emitted,” Bowman says.

Bringing new energy to search for clean fuels
Water oxidation advance aims at solar fuel

'Piedmont Divide' to bridge art and science

In a previous work called "Collector," above, John Grade created tusk-like forms that were used as oyster beds in Washington's Willapa Bay.

Environmental artist John Grade comes to Atlanta as an Emory artist-in-residence Nov. 6-19 to design and build large-scale sculptural installations. His project, "Piedmont Divide" will visually and conceptually link the campus Quadrangle and Lullwater Preserve. Using materials derived from indigenous plants and trees, Grade will relate the form and construction method of the two installations to Emory’s research on West Nile virus and worldwide water sustainability.

The Emory Visual Arts Gallery will function as a working studio, available to the public as "Piedmont Divide" unfolds. Area residents are invited to participate as volunteers on the project. Grade’s residency also includes a follow-up visit in the spring to oversee the disassembly of the sculpture, as part of a larger creative arts performance. For more info, visit:

The ultimate goal of the "Piedmont Divide" collaboration is to raise environmental awareness in Emory and Atlanta.

Grade’s sculptures are shaped by natural landscapes, often changing form throughout their lifespans. One example is his 2007 wooden sculpture, "Collector," which was submerged in Washington’s Willapa Bay, where it acted as an oyster bed. After the oysters were eaten by Grade and friends, the tusk-like forms were transported on the grill of Grade’s pick-up truck to a slot canyon in Little Death Hollow, Utah. There, covered with insects from the ride, it was washed clean by flooding.

A few things you may not know about water
Sewage raises West Nile virus risk

Thursday, October 13, 2011

Captive chimps up for endangered status

A wild adult male chimpanzee, above, at Gombe National Park in Tanzania, where Thomas Gillespie's lab is working with the Jane Goodall Institute to understand the pathogens responsible for declining chimp populations. Mahale, a site near Gombe, is one of the confirmed places where human visitors have accidentally infected chimps with fatal respiratory pathogens. Photo by Matthew Heintz.

Currently, it is legal in the United States to keep a chimpanzee as a pet, and to dress the animal up and use it in movies, or for other entertainment purposes. A group of petitioners is seeking to ban those practices, including the Association of Zoos and Aquariums, the Jane Goodall Institute, the Pan African Sanctuary Alliance and the Wildlife Conservation Society. They have asked the U.S. Fish and Wildlife Service to extend endangered status protection to captive chimpanzees in this country.

The Fish and Wildlife Service is now reviewing the matter, and is accepting comments from experts and the general public through October 31.

Thomas Gillespie, a primate disease ecologist at Emory, is among the expert petitioners.

Gillespie, left, speaking at a recent symposium on ape health in Kyoto, Japan.

Following is a letter to the Parks and Wildlife Service from Gillespie:

I am writing in regard to the request for information concerning the status of chimpanzees, and to voice my professional opinion that all chimpanzees, captive and wild, should be correctly classified as an endangered species within the Endangered Species Act (ESA) of the United States.

I am an associate professor of global health and biodiversity conservation with faculty appointments in the Department of Environmental Studies, the Rollins School of Public Health and the program in Population Biology, Ecology and Evolution at Emory University.

Currently, wild chimpanzees are listed as endangered under the ESA, yet captive chimpanzees in the United States are only considered “threatened” and are thereby deprived of the protections afforded to endangered species. Chimpanzees are the only species that suffers such “split-listing,” since all other endangered animal species are afforded endangered status whether wild or captive-born. One unfortunate outcome of this policy loophole is that private citizens can buy and sell chimpanzees as pets or use them for entertainment purposes, activities with demonstrated negative effects on ape welfare and public perception of conservation status.

Wild chimpanzee populations are declining, and a global effort is needed to save the species from extinction. It is important to note that wild chimpanzees are more endangered today than they were in 1990 (when wild populations were listed as endangered, and all threats to chimpanzee survival needed to be addressed.) Thus, the United Stats must do everything in its power to promote chimpanzee conservation, including regulating the use of captive chimpanzees. We send a confusing message to citizens and governments of ape range-states when the United States pushes for increased protection abroad while not protecting chimpanzees domestically.

In addition to my concerns raised above, I would like to elaborate on a threat to wild chimpanzees that relates directly to captive chimpanzees not receiving the protections afforded to all other endangered species. There is now overwhelming evidence that even mildly pathogenic human respiratory pathogens are capable of causing high rates of mortality in wild chimpanzee populations. If precautions are not enforced, tourists and researchers can be responsible for introducing such pathogens to wild chimpanzee populations as we have witnessed repeatedly in recent years.

Although guidelines have been implemented at chimpanzee tourism sites to reduce the risk of transmission of such pathogens, enforcement is variable. Tourists arrive at chimpanzee tourism sites after a lifetime of experiencing countless images of chimpanzees in advertising, films and television programs portraying human-chimpanzee contact and proximity. Many tourists are disappointed when they learn that they will not be allowed to touch or hold a wild chimpanzee. Tourists often push their guides to allow them to get closer to chimpanzees or fail to move away from chimps when they approach as mandated. Guides are put in a difficult situation of wanting to enforce guidelines to protect the apes, but not wanting to risk losing a substantial tip if tourists are disappointed by their experience. This is not a hypothetical situation, this is something that I have witnessed countless times over the past 14 years while conducting research at a diversity of sites in Sub-Saharan African that host chimpanzee tourism.

Thomas Gillespie

A wild view of 'Planet of the Apes'
Gorillas cope with people in their midst

Tuesday, October 11, 2011

A few things you may not know about water

"Water Study" will lead participants through a "scientific experiment" in campus creeks.

By Carol Clark

Chances are you haven’t thought much about water lately. Unless you are a rancher in drought-stricken Texas, and you just relocated your cattle out of state because nothing is left for them to eat. Or if you are a young girl in rural Kenya, facing a miles-long walk to fetch water for the family, and a return trip bearing the heavy load.

We tend to take water for granted in lush Atlanta. But it’s moving front and center at Emory this year, through a series of events that will draw from science, art, the environment and the imaginations of all those who want to dive into the experience.

You can fall in behind dancers in haz-mat suits, as they lead people through a “scientific experiment” along the creek in Baker Woodlands. The interactive performance, called “Water Study,” takes place every evening from Oct. 15 to 19. And you can join a line of people accumulating across campus at noon on Oct. 18, to pour water from vessel to vessel until the last drop vanishes.

More water-related surprises are on the way in November, and in the spring. To prime the pump, so to speak, here are a few random facts about water.

Two-thirds of the Earth’s surface is covered in water, and all of that water came from space after the planet cooled down. One theory is that the water came from meteorites. The Herschel telescope, however, recently zeroed in on the properties of a comet, and learned it has water with the same deuterium-to-hydrogen ratio as Earth’s oceans.

Texas is experiencing its most severe one-year drought ever. Drier than normal conditions are expected to continue at least for months, and possibly until 2020, according to a state climatologist. The National Weather Service reports that livestock and agriculture losses have topped $5.2 billion. During the past 11 months, more than 6,000 square miles have burned across the state, an area larger than the state of Connecticut.

Comet McNaught shoots over the Pacific Ocean off Chili. Comets are like icy time capsules that may hold clues to our solar system’s evolution, including the source of Earth’s water. Credit: European Southern Observatory.

Water use has been growing at more than twice the rate of population increase during the last century, according to the Food and Agriculture Organization. By 2025, the FAO projects that two-thirds of the world population could be under stress conditions of water scarcity.

Globally, diarrhea is the leading cause of illness and death, and 88 percent of these deaths are due to a lack of sanitation facilities and safe water for drinking and hygiene, according to the United Nations. More than one in six people worldwide don’t have access to safe water.

Environmentalist and author Janisse Ray, on the banks of the Altamaha River. Photo by Carol Clark.

Georgia’s Altamaha River flows 135 miles across the bottom third of the state. Its banks are mostly wetland wilderness, and it is one of the few almost entirely undammed rivers in the United States. Environmentalist Janisse Ray describes the river in her new book Drifting into Darien: “The Altamaha’s size and nature have led it to be called Georgia’s Little Amazon, the most powerful river east of the Mississippi. Despite this distinction, most people remain unaware of it, which prompted Reg Murphy in his National Geographic article to call it 'the river almost nobody knows.'"

Now is a great time of year to paddle the Altamaha.

What we can learn from African pastoralists
Famine in Somalia driven by conflict
Sewage raises West Nile virus risk

Monday, October 10, 2011

Lesson No. 1: Learn to relax

Laura Diamond writes in the Atlanta Journal-Constitution:

About 75 college students sat on yoga mats, taking deep breaths as they contoured their bodies in different positions.

Last week’s yoga class taught Emory University freshmen how to make their bodies stronger and more flexible. Students also learned how yoga could reduce their stress — a crucial lesson as they embarked on their first college midterms all while adjusting to living on their own.

This balance of physical, emotional and spiritual well-being is a cornerstone of Emory University’s new Health 100 course, a requirement for all freshmen.

Several colleges across the country have added programs and requirements in recent years to address students’ physical health and combat the obesity epidemic. But Emory officials have taken a more holistic approach and created a course based on the research they’ve conducted on predictive health, which stresses maintaining good health and preventing disease as opposed to just curing illnesses people already have.

The course abandoned the “do this, don’t do that” mentality found in most health lectures, said Michelle Lampl, director of the Emory Center for the Study of Human Health. “We are not here to admonish or preach to the students,” she said. “We are teaching them a healthier approach to life. They didn’t come here to fill their heads while destroying their bodies.”

Rather than professors lecturing to students, upperclassmen teach the class through small-group discussions. They help the freshmen come up with health goals and give advice on different aspects of college life.

Read the whole article in the AJC.

A personalized approach to health education
Can meditation calm your kids?
Are hugs the new drugs?
Grandma was right: Babies really do wake up taller
That diaper is loaded with data

Wednesday, October 5, 2011

A geologist paints Darwin

By Carol Clark

Emory geologist Woody Hickcox feels a special kinship with Charles Darwin, and it’s not just because of a slight physical resemblance. “Nothing in geology or the natural world makes any sense without his theory of evolution,” Hickcox says. “He’s sort of the kindly grandfather of us all.”

Hickcox, a senior lecturer in the department of environmental studies, has taught at Emory for 27 years. He’s also a talented artist. His murals and paintings of nature, especially birds, can be seen throughout the Math and Science Building.

When Hickcox was invited to create a piece in celebration of the Fernbank Museum’s special Darwin exhibit, he chose to do a larger-than-life, impressionistic portrait of the English naturalist, who established that all species of life have descended from a common ancestor.

“I feel very close to him as a scientist, and painting him brings me closer to him as a person. The melding of the two is greater than the sum of the parts,” Hickcox says. “You can see in his face that he went through a lot, that there were a lot of trials and tribulations in his life, aside from the science that we are all struggling to understand.”

Hickcox says that while painting the portrait, he thought about Darwin as “a normal person,” instead of the myth. “He’s not the devil. He’s not really different from any one else. He’s just a really smart guy who, in a sense, got really lucky to go on the ship he went on. And he was one of those people who were able to bring a tremendous amount of material together.”

The portrait of Darwin is part of the show “Selections,” works of art inspired by evolution, that will be on view at the Fernbank throughout the Darwin exhibit. The eight Georgia artists in the show include other scientists from the department of environmental studies: Anthony Martin and Berry Brosi, and former faculty member Lore Rattan, who left Emory last year to pursue her art full-time.

You can meet all of the artists, and ask them questions about their work, at the official opening party for “Selections,” on Friday, October 14, from 6:30 to 7:30 pm at Fernbank.

The art of fossil hunting
Teaching evolution enters new era

Monday, October 3, 2011

'Contagion' and emerging disease threats

Here's an excerpt from an article by Lynne Peeples on the Huffington Post:

Our proximity to migrating animals, rodents and livestock, combined with environmental upheaval, has created conditions that make animal-borne epidemics more likely –- a theme the new film "Contagion" embraces with enough zeal to throw Gwyneth Paltrow into a fit of lethal convulsions.

Animals carry a number of viruses, usually without consequence to themselves, but those same viruses can prove deadly to another species. Humans have simply yet to cross paths with most of these pathogens.

"In the future, we're going to come across viruses that have been around for millions of years in obscure animals," says Peter Daszak, president of EcoHealth Alliance, a New York-based organization of scientists dedicated to conserving biodiversity.

While science can typically track down creatures that are hosts to threatening viruses, such human factors as population growth, income inequality, environmental degradation, climate change and even global travel may all play a much more decisive role in unleashing outbreaks of deadly and hard-to-control diseases.

"Microbes are out there and they are paying attention," says James Hughes, a professor of medicine and public health at Emory University, who spent about three decades with the CDC. "They are pretty good probes for weaknesses in the public health system."

Just look around, analysts warn. As deforestation and development shrinks the margins between civilization and the untrammeled regions globally, diseases will have more opportunities for transmission to humans.

Intensifying agricultural production can also facilitate epidemics, which is why the United States made Daszak's watchlist for countries that are likely to be home to emerging infectious diseases. Combined with the overuse of antibiotics, tightly penned livestock such as chickens and cows can also play a role in jumpstarting outbreaks (as happened recently with both salmonella and E. coli threats).

Read the whole article at the Huff Post.

Contagion: The cough heard around the world
West Nile virus up in Atlanta mosquitos
Mosquito monitoring saves lives and money
From deadly flu to dengue fever, rising risks