Saturday, May 31, 2008

Research news: Ancient Clump Reveals Greenland Eskimos' Roots

The News:
Ancient Clump Reveals Greenland Eskimos' Roots
Morning Edition, May 30, 2008 · A 3,000-year-old clump of human hair found frozen in Greenland may have solved a scientific mystery: Where did all the ancient Eskimos come from?
The ancient clump of hair looks like something you'd sweep off a barbershop floor. "It's kind of brown, got a bit of dirt in it, a bit of twigs, but ... it looks [in] remarkably good condition," says biologist Thomas Gilbert of the University of Copenhagen.
University of Copenhagen researchers had spent months in Greenland trying to find human remains, with no success. They then learned of this hair sample, which was discovered in the 1980s in Disko Bay, in western Greenland, and was being kept in a museum collection.
And the hair yielded something extremely rare — the DNA of some of the earliest humans to live in the Arctic. By studying that DNA, researchers say they've been able to answer a longstanding question: Are modern Eskimos descended from ancient Native Americans, or did they come from somewhere else? Read on...

The Research:
Read the research behind this story in the journal Science.

Thursday, May 29, 2008

Research news: Monkeys control prosthesis with mind

The News:
Monkeys control prosthesis with mind
Macaques move a mechanical arm with thought in a new study, adopting it as their own.
By Benedict CareyThe New York Times
Article Last Updated: 05/29/2008 12:22:36 AM MDT

A monkey uses a mechanical arm to remove a marshmallow from a skewer that a researcher holds and bring the treat to its mouth in these undated handout images. The new study suggests that brain-controlled prostheses, while not practical, are at least technically within reach.
Two monkeys with tiny sensors in their brains have learned to control a mechanical arm with just their thoughts, using it to reach for and grab food and even to adjust for the size and stickiness of morsels when necessary, scientists reported Wednesday.
The report, released online by the journal Nature, is the most striking demonstration to date of brain-machine interface technology.
Scientists expect that technology will eventually allow people with spinal-cord injuries and other paralyzing conditions to gain more control over their lives.
The findings suggest that brain-controlled prosthetics, while not practical, are at least technically within reach.
In previous studies, researchers showed that humans who had been paralyzed for years could learn to control a cursor on a computer screen with their brain waves and that nonhuman primates could use their thoughts to move a mechanical arm, a robotic hand, a robot on a treadmill or a small vehicle.
The new experiment goes a step further. In it, the monkeys' brains seem to have adopted the mechanical appendage as their own, refining its movement as it interacted with real objects in real time. The monkeys had their own arms gently restrained while they learned to use the added one. Read on...

The Research:
Read the research behind this story in the journal Nature.

Wednesday, May 28, 2008

Research news: Childhood obesity "epidemic" seems to have leveled off

The News:
Childhood obesity "epidemic" seems to have leveled off
By Alan Zarembo Los Angeles Times
Article Last Updated: 05/28/2008 01:14:54 AM MDT

The stunning three-decade rise in childhood obesity that prompted the government to declare an "epidemic" of fat appears to have leveled off, although the rate is still more than three times as high as in the 1970s, researchers reported Tuesday.
The analysis was based on data from tens of thousands of children showing that the percentage of obese youngsters has been roughly stable since 1999 in every age and racial group they surveyed.
The level of obesity "is still too high," said lead author Cynthia Ogden, an epidemiologist with the federal Centers for Disease Control and Prevention. But she added, "Maybe there is some cause for optimism."
What caused the plateau is a mystery. A leading possibility is that educational and regulatory campaigns to get children to eat less junk food and exercise more have begun to pay off.
The findings "may signal that this national epidemic is not an unstoppable force," said Dr. Risa Lavizzo-Mourey, president of the Robert Wood Johnson Foundation, which has committed $500 million to promoting physical activity and improving school nutrition.
"When parents, government, schools, the food and beverage industries, other businesses, and the nonprofit and philanthropic sectors work together, we can make progress, and we can reverse this epidemic," she said in a statement.
Some researchers, however, said the answer could be that the epidemic has simply reached a saturation point — kids just can't get any fatter. read on...

The Research:
Read the research behind this story in the Journal of the American Medical Association.

Sunday, May 18, 2008

Research News: Radar images of red planet's north pole show layers of ice, dust

The News:
Radar images of red planet's north pole show layers of ice, dust
By the Los Angeles Times
Article Last Updated: 05/16/2008 01:33:00 AM MDT
Mars' north pole, like a French parfait, comes in layers. Scientists analyzing radar images from NASA's Mars Reconnaissance Orbiter spacecraft have found up to seven distinct layers of ice and dust beneath the north pole. Roger J. Phillips, a scientist with the Southwest Research Institute in Boulder, said the layering probably was caused by changes in the planet's orbit in the last 4 million years.

The Research:
Read the research behind this story in the journal Science.

Wednesday, May 14, 2008

Research News: Psychological Stress Linked To Overeating

The News:
Psychological Stress Linked To Overeating
ScienceDaily (May 14, 2008) — Researchers at the Yerkes National Primate Research Center, Emory University, have found socially subordinate female rhesus macaques over consume calorie-rich foods at a significantly higher level than do dominant females. The study is a critical step in understanding the psychological basis for the sharp increase in obesity across all age groups since the mid-1970s.

The Research:
Read the research behind this story in Physiology & Behavior.

Friday, May 9, 2008

Research news: Sahara gradually dried up over 6,000 years

The News:
Study: Sahara Gradually Dried Up Over 6,000 Years
Talk of the Nation, May 9, 2008 · What made the Sahara Desert go dry — and are there ancient waters still hidden below the sands? In a study published in the journal Science researchers argue that the drying of the Sahara took place over thousands of years. The controversial finding contradicts several previous studies, which argue that the Sahara dried up much more suddenly. Read on...

The Research:
Read the research articles behind this story in the journal Science:
"How the Sahara Became Dry."
"Climate-Driven Ecosystem Succession in the Sahara: The Past 6000 Years"

Thursday, May 8, 2008

Research news: Platypus is even more strange than it looks

The News:
Platypus Is Even More Strange Than It Looks
by Joe Palca
All Things Considered, May 7, 2008 · With its furry body and duck-billed face, the platypus is nothing if not bizarre looking. But scientists have confirmed that its strangeness is more than skin deep — after unraveling the animal's genome, they have discovered that even its genes are odd.
Most of the platypus's genes control characteristics typical of mammals, such as genes for making milk and fur. Unlike other mammals, however, the platypus lays eggs instead of birthing live young. Geneticist Richard Wilson of Washington University in St. Louis and his colleagues report in this week's issue of Nature that they have identified platypus genes that make hard-shelled eggs — much like the genes of birds. Read on...

The Research:
Read the research behind this story in the journal Nature.

Wednesday, May 7, 2008

Research news: Ibuprofen linked to reduced risk of Alzheimer's disease

The News:
Ibuprofen Linked To Reduced Risk Of Alzheimer's Disease
ScienceDaily (May 6, 2008) — Long-term use of ibuprofen and other drugs commonly used for aches and pains was associated with a lower risk of Alzheimer's disease, according to a study published in the May 6, 2008, issue of Neurology®, the medical journal of the American Academy of Neurology. Previous studies have shown conflicting results, but this is the longest study of its kind.
For the study, researchers identified 49,349 US veterans age 55 and older who developed Alzheimer's disease and 196,850 veterans without dementia. The study examined over five years of data and looked at the use of several non-steroidal anti-inflammatory drugs (NSAIDs). The veterans received medical care and prescriptions through the VA Health Care system.
The study found people who specifically used ibuprofen for more than five years were more than 40 percent less likely to develop Alzheimer's disease. Results also showed that the longer ibuprofen was used, the lower the risk for dementia. In addition, people who used certain types of NSAIDs for more than five years were 25 percent less likely to develop Alzheimer's disease than non-users. Read on...

The Research:
Read the research behind this story in the journal Neurology.

Tuesday, May 6, 2008

Research news: Cervical-cancer virus linked to cancers in men

The News:
Cervical-cancer virus linked to cancers in men
By Katy Human The Denver Post
Article Last Updated: 05/06/2008 02:28:45 AM MDT
A sexually transmitted virus that causes cervical cancer has been linked to cancers of the tonsil and tongue — diseases that have been on the rise in men for the past 30 years, according to a study by a Colorado Springs doctor and researcher.
Among Colorado men, such throat cancers have become 37 percent more common since 1980, compared with a national increase of 11 percent.
"Nobody knows that this is going on, and it's important to understand the risk," said Joel Ernster, a professor at the University of Colorado Denver School of Medicine and principal author of the study, which appeared in the journal Laryngoscope.
The trends point to oral sex as a likely mode of transmission and have prompted some to call for boys to be vaccinated against the human papilloma virus, Ernster said.
Girls can already receive a vaccine to prevent cervical cancer.
"Based on what they know right now, why the hell aren't they giving it to boys?" asked Jon Helander, 56, a patient of Ernster's in Colorado Springs.
Helander went through radiation and chemotherapy to fight a virus-related tongue cancer earlier this year and said he's frustrated that his son, 21, can't be vaccinated against the virus, as his daughter, 23, has been. Read on...

The Research:
Read the research by University of Colorado Denver School of Medicine researchers in the journal Laryngoscope.

Monday, May 5, 2008

Research news: New Idea For How Anti-aging Products Delay Ripening Of Fruit And Wilting Of Flowers

The News:
New Idea For How Anti-aging Products Delay Ripening Of Fruit And Wilting Of Flowers
ScienceDaily (May 5, 2008) — When plants encounter ethylene, a gas they also produce naturally as a hormone, the result is softening and ripening in the case of fruit, and wilting and fading in the case of flowers -- all of which ethylene promotes.
To delay these effects, growers spray plants with products available in the market today, such as EthylBlocTM for flowers and SmartFreshSM for fruits and vegetables, that contain a compound that blocks ethylene's action on plants.
But how this compound, 1-methylcyclopropane or 1-MCP, works at the molecular level remains uncertain despite several chemical pathways chemists have proposed in the scientific literature.
Now, in a research paper published in the April issue of Chemistry & Biology, a team led by Michael Pirrung, a professor of chemistry and the holder of the University of California Presidential Chair in Chemistry at UC Riverside, offers a novel pathway for how "anti-aging" products like EthylBloc and SmartFresh block ethylene in plants, delaying the plants' demise and allowing people to enjoy their beauty and products for longer than nature allows. Read on...

The Research:
Read the research behind this story in the journal Chemistry & Biology.

Saturday, May 3, 2008

Research news: Young songbirds babble before they learn to sing

The News:
Young Songbirds Babble Before They Learn To Sing
ScienceDaily (May 3, 2008) — Young songbirds babble before they can mimic an adult's song, much like their human counterparts. Now, in work that offers insights into how birds--and perhaps people--learn new behaviors, MIT scientists have found that immature and adult birdsongs are driven by two separate brain pathways, rather than one pathway that slowly matures.
"The babbling during song learning exemplifies the ubiquitous exploratory behavior that we often call play but that is essential for trial-and-error learning," comments Michale Fee, the senior author of the study and a neuroscientist in the McGovern Institute for Brain Research at MIT and an associate professor in MIT's Department of Brain and Cognitive Sciences.
Early on, baby zebra finches produce a highly variable, babbling song. They practice incessantly until they can produce the stereotyped, never-changing song of adults. "This early variability is necessary for learning, so we wanted to determine whether it is produced by an immature adult motor pathway or by some other circuit," Fee explains. Read on...

The Research:
Read the research behind this story in the journal Science.

Friday, May 2, 2008

Research news: Selfishness may be Altruism's Unexpected Ally

The News:
Selfishness May Be Altruism's Unexpected Ally
ScienceDaily (May 2, 2008) — Just as religions dwell upon the eternal battle between good and evil, angels and devils, evolutionary theorists dwell upon the eternal battle between altruistic and selfish behaviors in the Darwinian struggle for existence. In a new study published in the Proceedings of the National Academy of Sciences (PNAS), evolutionary theorists at Binghamton University suggest that selfishness might not be such a villain after all.
Omar Tonsi Eldakar and David Sloan Wilson propose a novel solution to this problem in their article, which is available in the online Early Edition of PNAS. They point out that selfish individuals have their own incentive to get rid of other selfish individuals within their own group. Read on...

The Research:
Read the research behind this story in the journal Proceedings of the National Academy of Sciences (click on Full Text pdf)

Thursday, May 1, 2008

Research news: Ancient ecosystems organized much like our own

The News:
Ancient Ecosystems Organized Much Like Our Own
ScienceDaily (May 1, 2008) — Similarities between half-billion-year-old and recent food webs point to deep principles underpinning the structure of ecological relationships, as shown by researchers from the Santa Fe Institute, Microsoft Research Cambridge and elsewhere. Analyses of Chengjiang and Burgess Shale food-web data suggest that most, but not all, aspects of the trophic structure of modern ecosystems were in place over a half-billion years ago. It was an Anomalocaris-eat-trilobite world, filled with species like nothing on today's Earth. But the ecology of Cambrian communities was remarkably modern, say researchers behind the first study to reconstruct detailed food webs for ancient ecosystems. Their paper suggests that networks of feeding relationships among marine species that lived hundreds of millions of years ago are remarkably similar to those of today. Read on...

The Research:
Read the research behind this story in the journal PLoS: Biology.