A young brain for an old bee
We are all familiar with the fact that cognitive function declines as we get older. Moreover, recent studies have shown that the specific kind of daily activities we engage in during the course of our lives appears to influence the extent of this decline. view more (2009-07-01)
... 2009.
The oldest bees in a colony are the foragers - a task that demands a high ... the nurse bees of a colony, some of the foragers will revert to nursing behaviour and ... their brains become 'young' again. We thus hope to study the mechanisms responsible for age-dependent effects, like oxidative damage, and also to discover new ways to act against ...
Implant bacteria, beware: Researchers create nano-sized assassins
Staphylococcus epidermidis is quite an opportunist. Commonly found on human skin, the bacteria pose little danger. But S. epidermidis is a leading cause of infections in hospitals. view more (2009-06-26)
... protective film to shield the colony from antibiotics. According to a study in the journal Clinical Infectious Diseases, up to 2.5 percent of hip and knee implants alone in the United States become infected, affecting thousands of patients, sometimes fatally.
More ominously, there is no effective antidote for infected implants. The only way to get rid of the bacteria is to ...
Human term placenta a new abundant source of hematopoietic cells
Investigators at Children's Hospital Oakland Research Institute, Oakland, California found a way to obtain large numbers of hematopoietic stem cell from human term placenta. view more (2009-06-25)
... abundant amounts of CD34+ CD133+ colony-forming cells, as well as other primitive hematopoietic progenitors, suitable for ... live hematopoitic stem cells, or colony-forming units in culture that could be obtained from placentas was ... an order of magnitude larger than the number of hematopoietic stem cells obtained from cord blood from the same source. Hematopoietic stem cells which maintain their differentiation capacity, ...
Crustacean shell with polyester creates mixed-fiber material for nerve repair
In the clothing industry it's common to mix natural and synthetic fibers. Take cotton and add polyester to make clothing that's soft, breathable and wrinkle free. view more (2009-06-17)
... stable in solution, resistant to collapse and also pliable, so that surgeons can suture it to ... stress and it's going to collapse."
Zhang and colleagues developed an alternative. The first component of their ... material, polycaprolactone, is a strong, flexible, biodegradable polyester commonly used in sutures. It is not suitable on its own for use as a nerve guide because water-based cells ...
Complaints of fatigue and tiredness in people with OSA improve with CPAP treatment
A study in the June 15 issue of the Journal of Clinical Sleep Medicine shows that the complaints of fatigue and tiredness in patients with obstructive sleep apnea (OSA) improved significantly with good adherence to continuous positive airway pressure (CPAP) therapy, suggesting that - like the symptom of excessive daytime sleepiness - these... view more... (2009-06-16)
... back of the throat to collapse and block the upper airway. This leads to partial reductions (hypopneas) and complete pauses (apneas) in breathing that can produce abrupt reductions in blood oxygen saturation. Most people with OSA snore loudly and frequently, and they often experience excessive daytime sleepiness.
The authors suggest that their findings are in agreement with previous research demonstrating that ...
Birth of a star predicted
The astrophysicist João Alves, director of the Calar Alto Observatory in Almeria, and his colleague Andreas Bürkert, from the German observatory in the University of Munich, believe that "the inevitable future of the starless cloud Barnard 68" is to collapse and give rise to a new star, according to an article which has been... view more... (2009-06-10)
... cloud Barnard 68" is to collapse and give rise to a new star, according to an ... state, and that it will collapse "soon" - within a period of around 200,000 years.
The images ... were generated, making the system collapse and creating the ideal conditions for the formation of a ... will lead to their subsequent collapse. According to Bürkert and Alves' calculations, ...
Work of Field Museum scientist addresses question of chance in evolution
As Darwin observed, natural selection leading to adaptation of individuals and populations is occurring gradually and all the time. But over very long spans of time, the major channels of genetic organization, organism form, and the different ways organisms develop arose as outcomes of history-dependent variation that is now channeled, or... view more... (2009-06-10)
... predators and parasites on the colony surface.
What is remarkable is that the molecular genealogy of the living species shows their origin only 15 million years ago, with the same trajectory as in the distant past! Evidence suggests that trajectory has occurred again and again in other groups. The authors argue that the original trajectory was highly contingent on a set ...
Insomniac flies resemble sleep-deprived humans
Researchers at Washington University School of Medicine in St. Louis have created a line of fruit flies that may someday help shed light on the mechanisms that cause insomnia in humans. view more (2009-06-03)
... overall vulnerability and risk of collapse, it also seems to boost certain factors that help resist ... certain factors that help resist collapse."
When researchers screened the genome of the insomniac flies for changes ... in gene activity levels, they found altered activity levels for genes involved in metabolism, nerve cell activity and sensory perception. Shaw's lab had previously demonstrated that the activity ...
Did the North Atlantic fisheries collapse due to fisheries-induced evolution?
The Atlantic cod has, for many centuries, sustained major fisheries on both sides of the Atlantic. However, the North American fisheries have now largely collapsed. view more (2009-05-27)
... American fisheries have now largely collapsed. A new paper in the open-access, peer-reviewed journal PLoS ONE ... into possible mechanisms of the collapse of fisheries, due to fisheries-induced evolution.
Cod fishing is of highest ... to changes that preceded the collapse of northern cod at Newfoundland.
This finding further supports the hypothesis ... the hypothesis of an imminent collapse of Icelandic cod due to the ...
Necessity is the mother of invention for clever birds
Researchers at the Universities of Cambridge and Queen Mary, University of London have found that rooks, a member of the crow family, are capable of using and making tools, modifying them to make them work and using two tools in a sequence. view more (2009-05-26)
... to drop a stone to collapse a platform and acquire a piece of food, and subsequently showed the ability to choose the right size and shape of stone without any training.
Not only could they use stones to solve the task, but they were flexible in their tool choice, using and modifying sticks to achieve the same goal. When the correct ...
LSUHSC research describes function of key protein in cancer spread
Research led by David Worthylake, PhD, Assistant Professor of Biochemistry and Molecular Biology at LSU Health Sciences Center New Orleans, may help lay the groundwork for the development of a compound to prevent the spread of cancer. view more (2009-05-22)
... they may settle and form "colony" tumors. In their new location, the cancer cells continue growing. The spread of a tumor to a new part of the body is called metastasis. Most people who die of cancer have metastases at the time of their death, and metastatic disease is directly responsible for the majority of cancer deaths. This year, about ...
Melting threat from West Antarctic Ice Sheet may be less than expected, could hit US hardest
While a total or partial collapse of the West Antarctic Ice Sheet as a result of warming would not raise global sea levels as high as some predict, levels on the U.S. seaboards would rise 25 percent more than the global average and threaten cities like New York, Washington, D.C., and San Francisco, according to a new study. view more (2009-05-15)
While a total or partial collapse of the West Antarctic Ice Sheet as a result of ... the likelihood of a WAIS collapse and what implications such a catastrophic event would have for ... his colleagues found a WAIS collapse would only raise sea levels by 3.3 meters, or about ... time precipitating further breakup and collapse, according to existing theories.
The study authors ...
Threat from West Antarctica less than previously believed
The potential contribution to sea level rise from a collapse of the West Antarctic Ice Sheet (WAIS) have been greatly overestimated, according to a new study published in the journal Science. view more (2009-05-15)
... sea level rise from a collapse of the West Antarctic Ice Sheet (WAIS) have been greatly ... the case of a partial collapse, would experience the largest increases, threatening cities such as New ... the likelihood of a WAIS collapse and what implications such a catastrophic event would have for ... precipitating further break up and collapse.
For their calculations, the researchers assumed that ...
UCLA scientists identify how key protein keeps chronic infection in check
Why is the immune system able to fight off some viruses but not others, leading to chronic, life-threatening infections like HIV and hepatitis C? view more (2009-05-08)
... they don't get fed, they collapse on the track."
Without IL-21, the CD8 T-cells dwindled, even when the CD4 T-cells produced a robust response. The result indicates that the T-cells rely on IL-21 to resolve persistent infection.
"After the immune system loses CD8 T-cells, it's unable to clear the virus," Brooks said. "This tells us that IL-21 is a critical player in ...
Global monsoon drives long-term carbon cycles in the ocean
Monsoon is a global system, and many arrays of evidence indicate that it drives long-term cyclicity of the carbon reservoir in the global ocean. view more (2009-05-08)
... example, is responsible for the collapse of several Asian and African ancient cultures at ~ 4000 years ago. The same cyclicity is seen in the chemical composition of the air, such as methane concentration and isotope composition of air-bubbles captured in ice cores.
Now Wang found that the long-term cycles in the oceanic carbon reservoir also has a global monsoon origin. ... |
