WASHINGTON — A new, detailed record of rainfall fluctuations in ancient Mexico that spans more than twelve centuries promises to improve our understanding of the role drought played in the rise and fall of pre-Hispanic civilizations. Prior evidence has indicated that droughts could have been key factors in the fates of major cultures in ancient Mexico and Central America (Mesoamerica). But there have been many gaps in the paleoclimate record, such as the exact timing and geographic extension of some seemingly influential dry spells. The new, 1,238-year-long tree-ring ...

A growing global population has lead to increasing demands for food. Farmers around the world rely, at least in part on phosphorus-based fertilizers in order to sustain and improve crop yields. But the overuse of phosphorus can lead to freshwater pollution and the development of a host of problems, such as the spread of blue-green algae in lakes and the growth of coastal 'dead zones'. A further issue is that phosphorus comes from phosphate rock, a non-renewable resource of which there are limited supplies in such geopolitically charged areas as Western Sahara and China. Now, ...

New discoveries on how underwater ridges impact the ocean's circulation system will help improve climate projections. An underwater ridge can trap the flow of cold, dense water at the bottom of the ocean. Without the ridge, deepwater can flow freely and speed up the ocean circulation pattern, which generally increases the flow of warm surface water. Warm water on the ocean's surface makes the formation of sea ice difficult. With less ice present to reflect the sun, surface water will absorb more sunlight and continue to warm. U.S. Geological Survey scientists looked ...

COLUMBIA, Mo. – Starbucks recently announced a new-sized 31-ounce drink, the "Trenta," which will be in stores this spring. The mega-sized coffee joins the ranks of other energy drinks that can pack plenty of caffeine and calories. Ellen Schuster, a University of Missouri nutrition expert, says that Americans should be wary of extra calories and sugar in the quest for bigger, bolder drinks. "The sheer size of new coffee and energy drinks increases consumers' potential for unhealthy calorie and sugar consumption," said Schuster, state specialist for MU Extension and the ...

RENO, Nev. – A team of University of Nevada, Reno and University of Nevada, Las Vegas researchers have devised a new model for how Nevada's gold deposits formed, which may help in exploration efforts for new gold deposits. The deposits, known as Carlin-type gold deposits, are characterized by extremely fine-grained nanometer-sized particles of gold adhered to pyrite over large areas that can extend to great depths. More gold has been mined from Carlin-type deposits in Nevada in the last 50 years – more than $200 billion worth at today's gold prices – than was ever mined ...

They were called the Eighth Wonder of the World. Until the late 19th century, New Zealand's Pink and White Terraces along Lake Rotomahana on the North Island, attracted tourists from around the world, interested in seeing the beautiful natural formations created by a large geothermal system. But the eruption of Mt. Tarawera on June 10, 1886, buried the terraces in sediment and caused the lake basin to enlarge, engulfing the land where the terraces stood. For more than a century, people have speculated whether any part of the Pink and White Terraces survived the eruption. This ...

Mom's touch and diet – Claire-Dominique Walker, PhD, director, Neuroscience Research Division, Douglas Institute. The quality and quantity of maternal milk and maternal-infant contact impact the stress response of the adult offspring, according to recent research published in Developmental Psychobiology. "This manuscript reviews and highlights how critical factors early in life can shape the physiology and behaviour of adult offspring," says Claire-Dominique Walker, Douglas research scientist and study senior author. "For example, we have shown that, in rodent models, ...

Homeless people who do not get enough to eat use hospitals and emergency rooms at very high rates, according to a new study. One in four respondents to a nationwide survey reported not getting enough to eat, a proportion six times higher than in the general population, and more than two thirds of those had recently gone without eating for a whole day. The report will appear in the Journal of General Internal Medicine and has been released online. "The study is the first to highlight the association between food insufficiency and health care use in a national sample ...

(WASHINGTON, February 3, 2011) – For blood cancer patients at high risk of relapse, hematopoietic stem cell transplantation (HSCT), the transplantation of blood-forming stem cells, is one of best options for treatment and a potential cure. Unfortunately, the most common complication of HSCT is graft-versus-host disease (GVHD), a serious and often deadly post-transplant complication that occurs when the newly transplanted donor cells recognize the recipient's own cells as foreign and react by attacking the cells in the patient's body. A study published today in Blood, the ...

The Gerontological Society of America (GSA) — the nation's largest interdisciplinary organization devoted to the field of aging — commends the federal government's recent release of the "2010 Dietary Guidelines for Americans" and particularly applauds its inclusion of specific advice for older adults. Because more than one-third of children and more than two-thirds of adults in the U.S. are overweight or obese, the 7th edition of "Dietary Guidelines for Americans," issued by the Department of Agriculture and the Department of Health and Human Services, places stronger ...

BOULDER--The aggressive wolverine may not be powerful enough to survive climate change in the contiguous United States, new research concludes. Wolverine habitat in the northwestern United States is likely to warm dramatically if society continues to emit large amounts of greenhouse gases, according to new computer model simulations carried out at the National Center for Atmospheric Research (NCAR). The study found that climate change is likely to imperil the wolverine in two ways: reducing or eliminating the springtime snow cover that wolverines rely on to protect and ...

COLUMBIA, Mo. – Each year, 29,000 foster youths are released from care as they become adults. A University of Missouri foster care expert says these young people encounter tremendous challenges as they transition out of care. However, those who receive care benefits through age 21 have greatly improved outcomes. Clark Peters, assistant professor in the School of Social Work, says all states should consider extending benefits for foster youth. "The transition between foster care and the real world leaves many 18-year-olds without a place to stay, money, a job or reliable ...

When a laboratory rat learns how to reach for and grab a food pellet – a pretty complex and unnatural act for a rodent – the acquired knowledge significantly alters the structure of the specific brain cells involved, which sprout a whopping 22 percent more dendritic spines connecting them to other motor neurons. The finding, published in the journal Proceedings of the National Academy of Sciences by Mark H. Tuszynski, MD, PhD, professor of neurosciences and colleagues at the University of California, San Diego School of Medicine, underscores the brain's remarkable ability ...

OAK RIDGE, Tenn. Feb. 3, 2011 -- Researchers at the Department of Energy's Oak Ridge National Laboratory have developed a biohybrid photoconversion system -- based on the interaction of photosynthetic plant proteins with synthetic polymers -- that can convert visible light into hydrogen fuel. Photosynthesis, the natural process carried out by plants, algae and some bacterial species, converts sunlight energy into chemical energy and sustains much of the life on earth. Researchers have long sought inspiration from photosynthesis to develop new materials to harness the ...

(February 3, 2011) Those familiar with Chesapeake Bay know that its once-vast oyster population stands at a tiny fraction of its historical abundance. A new study by an international team including professor Mark Luckenbach of the Virginia Institute of Marine Science shows that the decline of oyster reefs is not just a local problem. The team's global comparison of oyster reefs past and present shows that oyster reefs are at less than 10% of their prior abundance in 70% of the 144 bays studied, ranging from China to England to Australia to Brazil. Overall, they estimate ...

WEST LAFAYETTE, Ind. -- Surgeons of the future might use a system that recognizes hand gestures as commands to control a robotic scrub nurse or tell a computer to display medical images of the patient during an operation. Both the hand-gesture recognition and robotic nurse innovations might help to reduce the length of surgeries and the potential for infection, said Juan Pablo Wachs, an assistant professor of industrial engineering at Purdue University. The "vision-based hand gesture recognition" technology could have other applications, including the coordination of ...

WASHINGTON, Feb. 3, 2011 — Not even the most avid fans could notice, but those spectacular aerial images of a brightly-lit Cowboys Stadium during Sunday's Super Bowl XLV symbolize one of the hottest new pieces of scientific intelligence about air pollution: Researchers have discovered — in a classic case of scientific serendipity — that the bright light from sports stadiums and urban street lights may boost daytime levels of ozone, a key air pollutant in many heavily populated areas. That's among the topics included in a broader article about the chemistry of air pollution ...

CORVALLIS, Ore. – Scientists are having a difficult time gauging the recovery of marine species from the Deepwater Horizon oil spill in the Gulf of Mexico because they lack sufficient data about historical population size and the distribution, growth rates and reproduction rates of many species. In a forum paper published this week in the journal Science, they call for a new research agenda that prioritizes systematic acquisition of baseline data for marine species. "It is impossible to diagnose whether a species is recovering or floundering if you don't have good data ...

GAINESVILLE, Fla. — Twenty years after biologists attempted to determine the ecological damages to marine life from the Exxon Valdez oil spill, scientists dealing with the BP disaster find themselves with the same problem: the lack of critical data to determine the ecological consequences of human-induced environmental disasters, a University of Florida researcher said. Writing in the Feb. 4 issue of the journal Science, Karen A. Bjorndal, a University of Florida biology professor and director of the Archie Carr Center for Sea Turtle Research, and other biologists said ...

Bar Harbor, Maine — Researchers at Dana-Farber Cancer Institute in Cambridge, Mass., in collaboration with Jackson Laboratory scientists, have identified a regulatory defect that drives lupus. Correcting the defect "may represent an effective therapeutic approach to systemic lupus erythematosus-like autoimmune disease," the researchers state in their research paper, published in the Proceedings of the National Academy of Sciences. The research team was led by Harvey Cantor, M.D., chair of the department of cancer immunology and AIDS at Dana-Farber, in collaboration with ...

Every day is a bad-air day on Saturn's largest moon, Titan. Blanketed by haze far worse than any smog belched out in Los Angeles, Beijing or even Sherlock Holmes's London, the moon looks like a dirty orange ball. Described once as crude oil without the sulfur, the haze is made of tiny droplets of hydrocarbons with other, more noxious chemicals mixed in. Gunk. Icky as it may sound, Titan is really the rarest of gems: the only moon in our solar system with an atmosphere worthy of a planet. This atmosphere comes complete with lightning, drizzle and occasionally a big, summer-downpour ...

Tropical Cyclone Yasi has continued moving through inland Queensland, Australia and has weakened to a tropical depression today. NASA and JAXA's TRMM satellite passed over Yasi as it continued to drop moderate to heavy rainfall. On February 3 at 0300 UTC (Feb. 2 at 10 p.m. EST/1 p.m. Australia local time) Tropical cyclone Yasi continued over land as a tropical storm. Yasi's maximum sustained winds were near 60 knots (69 mph/111 kmh). It was moving west-southwest near 20 knots/23 mph/37 kmh). It was located about 200 miles (321 km) southwest of Cairns, Australia near ...

PORTLAND, Ore. -- The pediatric cardiac team at Oregon Health & Science University Doernbecher Children's Hospital is the first in the region and one of a handful in the nation to implant a pulmonary heart valve without open-heart surgery. To date, four patients have received the landmark valve in the OHSU Pediatric and Adult Congenital Cardiac Catheterization Lab. All reported immediate improvement in their energy level and stamina. The device, called the Medtronic Melody® Transcatheter Pulmonary Valve, recently was approved by the Food and Drug Administration. The ...

ITHACA, N.Y. – Growing up poor increases a person's likelihood of health problems as an adult, but a new study led by a Cornell University environmental psychologist shows that being raised in a tight-knit community can help offset this disadvantage of poverty. The study, "Loosening the Link Between Childhood Poverty and Adolescent Smoking and Obesity : The Protective Effects of Social Capital" published in the January 2011 edition of the peer-reviewed journal Psychological Science, found that poor adolescents who live in communities with more social cohesiveness are ...

Being successful in school requires a combination of social, emotional, and academic competencies. A new analysis of more than 200 school-based social and emotional learning programs has found that such programs improve students' attitudes and behaviors, and in some cases, even boost academic performance. The study appears in the January/February issue of the journal, Child Development. It was conducted by researchers at Loyola University Chicago and the University of Illinois at Chicago. In the first large-scale meta-analysis of school programs that enhance students' ...