Παρασκευή, 31 Ιανουαρίου 2014

ScienceDaily: Top News

ScienceDaily: Top News

Up close and 3-dimensional: HIV caught in the act inside the gut

Posted: 30 Jan 2014 04:04 PM PST

HIV infection has many unhealthy consequences on the body, but in particular it messes up the gut. A new study reports the first three-dimensional ultra-structural study of HIV infection in vivo. Not only does it reveal details on how the virus quickly infects immune cells in the gut, using them as virus-producing factories, but it also highlights where the virus "hides out" deep within the intestinal tissue.

What your company can learn from NASA tragedies

Posted: 30 Jan 2014 01:44 PM PST

Scientists have been researching how NASA recognizes "near-miss" events ever since the Columbia shuttle was destroyed in flight 11 years ago Saturday. A new study finds recognition of near-misses goes up when leaders emphasize project significance and weigh safety over other goals.

Lab clocks 'hot' electrons: Plasmon-generated electrons timed moving from nanorods to graphene

Posted: 30 Jan 2014 01:44 PM PST

Scientists time "hot" electrons as they transfer from excited plasmons in gold nanorods to graphene. Plasmonic nanoparticles are becoming known for their ability to turn light into heat, but how to use them to generate electricity is not nearly as well understood. Scientists are working on that, too. They suggest that the extraction of electrons generated by surface plasmons in metal nanoparticles may be optimized.

Enhancing mussel conservation, pearl production

Posted: 30 Jan 2014 01:43 PM PST

Mollusk researchers are promoting freshwater mussel conservation and developing more robust and productive pearl-producing Chinese mussels.

Genetically diverse cancer cells key to brain tumor resistance

Posted: 30 Jan 2014 12:58 PM PST

For a cancer cell, it pays to have a group of eccentric friends. Like X-Men characters, a group of cancer cells with diverse physical traits is safer, because it takes different strategies to kill each member. The more diverse the group, the better the chances are for individual cells to survive and join forces as a cohesive tumor.

Sex-specific patterns of recovery from newborn brain injury revealed by animal study

Posted: 30 Jan 2014 12:28 PM PST

Physicians have long known that oxygen deprivation to the brain around the time of birth causes worse damage in boys than girls. Now a study by researchers conducted in mice reveals one possible reason behind this gender disparity and points to gender-specific mechanisms of brain repair following such injury.

More than one-third of women have hot flashes 10 years after menopause

Posted: 30 Jan 2014 12:28 PM PST

A team of researchers has found that moderate to severe hot flashes continue, on average, for nearly five years after menopause, and more than a third of women experience moderate/severe hot flashes for 10 years or more after menopause. Current guidelines recommend that hormone therapy, the primary medical treatment for hot flashes, not continue for more than 5 years.

Does caregiving cause psychological stress? Study of female twins says it depends

Posted: 30 Jan 2014 11:13 AM PST

A newly published study shows that the associations between caregiving and different types of psychological distress (depression, anxiety, perceived stress and perceived mental health) depend largely on a person's genes and upbringing -- and less so on the difficulty of caregiving.

Worry on the brain: Researchers find new area linked to anxiety

Posted: 30 Jan 2014 11:13 AM PST

Previous studies of anxiety in the brain have focused on the amygdala, but a team of researchers had a hunch that understanding a different brain area, the lateral septum (LS), could provide more clues into how the brain processes anxiety. Their instincts paid off -- the team has found a neural circuit that connects the LS with other brain structures in a manner that directly influences anxiety.

New computer, Edison, electrifies scientific computing

Posted: 30 Jan 2014 11:13 AM PST

A new supercomputer, named Edison, electrifies scientific computing. Edison can execute nearly 2.4 quadrillion floating-point operations per second (petaflop/s) at peak theoretical speeds.

To hear without being heard: First nonreciprocal acoustic circulator created

Posted: 30 Jan 2014 11:13 AM PST

Scientists have built the first-ever nonreciprocal circulator for sound that is able to break sound wave reciprocity. The device is a 'one-way road for sound' that transmits acoustic waves in one direction but blocks them in the other. With this device, you can listen without being heard.

Faster X-ray technology paves the way for better catalysts: Researchers observe a catalyst surface at work with atomic resolution

Posted: 30 Jan 2014 11:13 AM PST

By using a novel X-ray technique, researchers have observed a catalyst surface at work in real time and were able to resolve its atomic structure in detail. The new technique may pave the way for the design of better catalysts and other materials on the atomic level.

Trick identified that aids viral infection

Posted: 30 Jan 2014 11:12 AM PST

Scientists have identified a way some viruses protect themselves from the immune system's efforts to stop infections, a finding that may make new approaches to treating viral infections possible.

Savanna vegetation predictions best done by continent

Posted: 30 Jan 2014 11:12 AM PST

A "one-size-fits-all" model to predict the effects of climate change on savanna vegetation isn't as effective as examining individual savannas by continent, according to new research.

Drug trafficking leads to deforestation in Central America

Posted: 30 Jan 2014 11:12 AM PST

Add yet another threat to the list of problems facing the rapidly disappearing rainforests of Central America: drug trafficking. In a new study, researchers who have done work in Central America point to growing evidence that drug trafficking threatens forests in remote areas of Honduras, Guatemala, Nicaragua and nearby countries.

New genetic forms of neurodegeneration discovered

Posted: 30 Jan 2014 11:12 AM PST

Researchers report doubling the number of known causes for the neurodegenerative disorder known as hereditary spastic paraplegia (HSP). HSP is characterized by progressive stiffness and contraction of the lower limbs and is associated with epilepsy, cognitive impairment, blindness and other neurological features.

Piezoelectrics and butterflies: Now scientists know more about how the materials actually work

Posted: 30 Jan 2014 10:31 AM PST

Piezoelectrics, materials that can change mechanical stress to electricity and back again, are everywhere in modern life. Computer hard drives. Loudspeakers. Medical ultrasound. Sonar. But there are major gaps in our understanding of how they work. Now researchers believe they've learned why one of the main classes of these materials, known as relaxors, behaves in distinctly different ways from the rest. The discovery comes in the shape of a butterfly.

Researchers develop new tool to identify genetic risk factors

Posted: 30 Jan 2014 09:16 AM PST

Researchers developed a new biological pathway-based computational model, called the Pathway-based Human Phenotype Network, to identify underlying genetic connections between different diseases. The Pathway-based Human Phenotype Network mines the data present in large publicly available disease datasets to find shared SNPs, genes, or pathways and expresses them in a visual form.

Cell cycle speed is key to making aging cells young again

Posted: 30 Jan 2014 09:16 AM PST

Researchers identified a major obstacle to converting cells back to their youthful state -- the speed of the cell cycle, or the time required for a cell to divide. When the cell cycle accelerates to a certain speed, the barriers that keep a cell's fate on one path diminish. In such a state, cells are easily persuaded to change their identity and become pluripotent, or capable of becoming multiple cell types.

Precise gene editing in monkeys paves the way for valuable human disease models

Posted: 30 Jan 2014 09:16 AM PST

Monkeys are important for modeling diseases because of their close similarities to humans, but past efforts to precisely modify genes in primates have failed. Researchers have now achieved precise gene modification in monkeys for the first time using an efficient and reliable approach known as the CRISPR/Cas9 system. The study opens promising new avenues for the development of more effective treatments for a range of human diseases.

Climate study projects major changes in vegetation distribution by 2100

Posted: 30 Jan 2014 09:13 AM PST

An international research team has determined the distribution of species of vegetation over nearly half the world's land area could be affected by predicted global warming.

World's first butterfly bacteria sequenced: Suprising events found during metamorphosis

Posted: 30 Jan 2014 08:10 AM PST

For the first time ever, scientists have sequenced the internal bacterial makeup of the three major life stages of a butterfly species, a project that showed some surprising events occur during metamorphosis.

Signs point to sharp rise in drugged driving fatalities

Posted: 30 Jan 2014 08:10 AM PST

The prevalence of non-alcohol drugs detected in fatally injured drivers in the US steadily rose from 1999 to 2010 and especially for drivers who tested positive for marijuana. Researchers found that of 23,591 drivers who were killed within one hour of a crash, 39.7 percent tested positive for alcohol and 24.8 percent for other drugs. The prevalence of non-alcohol drugs rose from 16.6 percent in 1999 to 28.3 percent in 2010; for marijuana, rates rose from 4.2 percent to 12.2 percent.

Antibiotic 'smart bomb' can target specific strains of bacteria

Posted: 30 Jan 2014 08:09 AM PST

Researchers have developed a de facto antibiotic "smart bomb" that can identify specific strains of bacteria and sever their DNA, eliminating the infection. The technique offers a potential approach to treat infections by multi-drug resistant bacteria.

Bones of a previously unknown species prove to be one of the oldest seabirds

Posted: 30 Jan 2014 08:08 AM PST

Fossils discovered in Canterbury, New Zealand reveal the nature of one of the world's oldest flying seabirds. Thought to have lived between 60.5 and 61.6 million years ago, the fossil is suggested to have formed shortly after the extinction of dinosaurs and many marine organisms.

Researchers find novel approach for controlling deadly C. difficile infections

Posted: 30 Jan 2014 07:21 AM PST

Researchers have revealed the first molecular views showing how highly specific antibodies derived from llamas may provide a new method for controlling deadly infections from the opportunistic bacterial pathogen Clostridium difficile.

'Bubble CPAP' boosts neonatal survival rates: Helps babies struggling to breathe

Posted: 30 Jan 2014 07:21 AM PST

The first clinical study of a low-cost neonatal breathing system demonstrated that the device increased the survival rate of newborns with severe respiratory illness from 44 percent to 71 percent. A 10-month study of 87 patients in Blantyre, Malawi, found that treatment with low-cost "bubble CPAP" increased survival for severely ill premature babies as much as fourfold.

Vitamin A used in acne medicines may help autoimmune, transplant patients

Posted: 30 Jan 2014 07:21 AM PST

The same form of Vitamin A used by teenagers to combat acne might offer benefits that are more than skin deep. That's because an international team of researchers have found that it may also help keep the immune system under control for people with autoimmune disorders or those who have received transplants.

Engineered cardiac tissue model developed to study human heart

Posted: 30 Jan 2014 07:21 AM PST

When it comes to finding cures for heart disease, scientists have finally developed a tissue model for the human heart that can bridge the gap between animal models and human patients. Specifically, the researchers generated the tissue from human embryonic stem cells with the resulting muscle having significant similarities to human heart muscle.

Engineered virus effective against triple negative breast cancer cells, study shows

Posted: 30 Jan 2014 07:20 AM PST

Scientists have discovered a potential cure for one of the most aggressive and least treatable forms of breast cancer called "triple negative breast cancer."

Integration brings quantum computer a step closer

Posted: 30 Jan 2014 07:20 AM PST

Scientists have made an important advance towards a quantum computer by shrinking down key components and integrating them onto a silicon microchip.

Mysterious ocean circles off the Baltic coast explained

Posted: 30 Jan 2014 07:20 AM PST

Are they bomb craters from World War II? Are they landing marks for aliens? Since the first images of the mysterious ocean circles off the Baltic coast of Denmark were taken in 2008, people have tried to find an explanation. Now researchers finally present a scientific explanation.

Thyroid cancer cells become less aggressive in outer space

Posted: 30 Jan 2014 07:20 AM PST

For those who think that space exploration offers no tangible benefits, new research involving thyroid cancer may prove otherwise. Researchers show that some tumors which are aggressive on earth are considerably less aggressive in microgravity. By understanding the genetic and cellular processes that occur in space, scientists may be able to develop treatments that accomplish the same thing on Earth.

Self-aligning DNA wires for application in nanoelectronics

Posted: 30 Jan 2014 07:20 AM PST

Since miniaturization in microelectronics is starting to reach physical limits, researchers seek new methods for device fabrication. One candidate is DNA origami in which strands of the biomolecule self-assemble into arbitrarily shaped nanostructures. The formation of entire circuits, however, requires the controlled positioning of these DNA structures on a surface -- which is only possible using elaborate techniques. Researchers have come up with a simpler strategy which combines DNA origami with self-organized pattern formation.

Wallaby's perception of color is more similar to a dog than a quokka

Posted: 30 Jan 2014 07:20 AM PST

Biologists have recently discovered that a wallaby's perception of color is more similar to a dog than a quokka, sparking questions as to why marsupial color vision has evolved so selectively. By developing a pokies-like game for the wallabies, the research was able to determine exactly what the animals saw and how their color perception differed from other species.

Use of testosterone therapy linked to heart attacks in men under 65, study shows

Posted: 30 Jan 2014 06:36 AM PST

A study has observed a two-fold increase in the risk of a heart attack in men under 65 with a history of heart disease, shortly after use of testosterone therapy; that is, the external application of testosterone. Further, the study also confirmed earlier studies that found a two-fold increase in the risk of heart attack shortly after treatment in men older than 65.

Robot with a taste for beer? Electronic tongue can identify brands of beer

Posted: 30 Jan 2014 06:28 AM PST

Researchers have managed to distinguish between different varieties of beer using an electronic tongue. The discovery is accurate in almost 82% of cases. Beer is the oldest and most widely consumed alcoholic drink in the world.

Using rare earths to interpret certain fossils

Posted: 30 Jan 2014 06:28 AM PST

Until now, interpreting flattened fossils was a major challenge. Now, a new approach for the analysis of such fossils has been developed. This non-destructive method makes use of chemical elements known as rare earths. By locating and quantifying such elements in trace amounts, it is possible to improve interpretation of fossil morphology.

Geranium extracts inhibit HIV-1

Posted: 30 Jan 2014 06:28 AM PST

Extracts of the geranium plant Pelargonium sidoides inactivate human immunodeficiency virus type 1 (HIV-1) and prevent the virus from invading human cells. Scientists report that these extracts represent a potential new class of anti-HIV-1 agents for the treatment of AIDS.

Mirror-image nucleic acids as molecular scissors in biotechnology and molecular medicine

Posted: 30 Jan 2014 06:28 AM PST

Biochemist have now created mirror-image enzymes -- so-called Spiegelzymes -- out of nucleic acids. The Spiegelzymes can be used in living cells for the targeted cutting of natural nucleic acids.

New species of Goby fish discovered

Posted: 30 Jan 2014 06:28 AM PST

In 2013, a new species of goby was discovered in a stream on the main island of Okinawa. Stiphodon species spawn in freshwater streams and the larvae drift to the sea soon after being hatched. The larvae grow in the sea by feeding on plankton before they return to the freshwater habitat. While they are living in the sea, they can be transported by ocean currents to remote areas. How long they stay in the sea depends on the species of goby, and Stiphodon species are known to stay in the sea for a relatively long period of time.

Photon recoil provides new insight into matter: New precision spectroscopy allows unprecedented accuracy

Posted: 30 Jan 2014 06:28 AM PST

Quantum logic spectroscopy has now been significantly extended: the new method is called "photon-recoil spectroscopy" (PRS). In contrast to the original quantum logic technique, the new method enables the investigation of very fast transitions in atoms or molecules. With this new method, spectroscopic investigations will be possible on nearly any kind of particles.

RNA tail linked to protein production during embryogenesis, study shows

Posted: 30 Jan 2014 06:14 AM PST

Researchers have determined that poly(A) tails on messenger RNAs (mRNAs) shift their role in the regulation of protein production during early embryogenesis. This finding about the regulation of mRNA translation also provides insight into how microRNAs control protein production.

Disappearing snow increases risk of collapsing ice shelves in Antarctica

Posted: 30 Jan 2014 01:08 AM PST

A number of floating ice shelves in Antarctica are at risk of disappearing entirely in the next 200 years, as global warming reduces their snow cover. Their collapse would enhance the discharge of ice into the oceans and increase the rate at which sea-level rises. A rapid reduction of greenhouse gas emissions could save a number of these ice shelves, researchers say.

Infants know plants provide food, but need to see they're safe to eat

Posted: 30 Jan 2014 01:08 AM PST

Infants as young as six months old tend to expect that plants are food sources, but only after an adult shows them that the food is safe to eat, according to new research.

Blood and lymphatic capillaries grown for the first time in the lab

Posted: 30 Jan 2014 01:07 AM PST

Researchers have engineered skin cells for the very first time containing blood and lymphatic capillaries. They succeeded in isolating all the necessary types of skin cells from human skin tissue and engineering a skin graft that is similar to full-thickness skin. 

Heart transplant success improving, patients living longer

Posted: 30 Jan 2014 01:06 AM PST

Heart transplantation continues to be the "gold standard" treatment for end-stage heart failure, and a large number of patients now live 20 years or more after surgery.

Connectedness, human use of buildings shape indoor bacterial communities

Posted: 29 Jan 2014 03:48 PM PST

Microbes drawn from the dust in a university building have provided clues that could inspire future architectural designers to encourage a healthy indoor environment.

Slow reaction time linked with early death

Posted: 29 Jan 2014 03:48 PM PST

Having a slow reaction time in midlife increases risk of having died 15 years later, according to new research. Researchers looked at data from more than 5,000 participants, over a 15 year period. A total of 378 (7.4 percent) people in the sample died, but those with slower reaction times were 25 percent more likely to have died (from any cause) compared to those with average reaction times.

Deaths attributed directly to climate change cast pall over penguins

Posted: 29 Jan 2014 03:48 PM PST

Climate change is killing penguin chicks from the world's largest colony of Magellanic penguins, not just indirectly -- by depriving them of food, as has been repeatedly documented for these and other seabirds -- but directly as a result of drenching rainstorms and, at other times, heat, according to new finding.

Zebrafish use sunscreen also for camouflage

Posted: 29 Jan 2014 03:46 PM PST

For diurnal animals like zebrafish embryos, which grow up in shallow pools and are practically see-through, exposure to the sun constitutes a major problem since ultraviolet (UV) radiation damages DNA. Neurobiologists set about investigating which mechanisms zebrafish embryos use to protect themselves against the aggressive UV radiation. Interestingly, scientists have found that the UV-protection mechanism also doubles as camouflage. 

Improved ultrasound imaging provides an alternative way of visualizing tumors

Posted: 29 Jan 2014 03:46 PM PST

While ultrasound provides a less expensive and radiation-free alternative to detecting and monitoring cancer compared to technologies such as X-rays, CT scans and MRIs, the lower clarity and resolution of ultrasound has limited its use in cancer treatment. Researchers have overcome this limitation by combining ultrasound with a contrast agent comprised of micro-sized bubbles that pair with an antibody produced at elevated levels by many cancers.

A simple new way to induce pluripotency: Acid

Posted: 29 Jan 2014 03:44 PM PST

An unusual reprogramming phenomenon by which the fate of somatic cells can be drastically altered through changes to the external environment is described in two new articles.

Findings point to potential treatment for virus causing childhood illnesses

Posted: 29 Jan 2014 01:55 PM PST

Researchers have discovered a potential treatment for a viral infection that causes potentially fatal brain swelling and paralysis in children. The findings also point to possible treatments for related viruses including those that cause "common cold" symptoms.

From rivers to landslides: Charting the slopes of sediment transport

Posted: 29 Jan 2014 01:54 PM PST

The slope of streambeds has dramatic and unexpected effects on sediment transport. Experimental data from the flume lab show that gravity does not facilitate sediment transport in the expected manner. In very steep streambeds with a 22-degree or higher slope, sediment motion begins not with grains skipping and bouncing along the bottom of the streambed, but rather with a complete bed failure in which all the sediment is abruptly sent hurtling downstream as a debris flow.

Puzzling question in bacterial immune system answered

Posted: 29 Jan 2014 01:54 PM PST

Researchers have answered a central question about Cas9, an enzyme that plays an essential role in the bacterial immune system and is fast becoming a valuable tool for genetic engineering: How is Cas9 able to precisely discriminate between non-self DNA that must be degraded and self DNA that may be almost identical within genomes that are millions to billions of base pairs long.

Study measures how well Asian carp prevention effort will work

Posted: 29 Jan 2014 01:54 PM PST

Scientists have recently presented their findings of the effectiveness of different Asian carp prevention barriers.

ADHD medication saves lives on the road

Posted: 29 Jan 2014 01:54 PM PST

New research from Sweden shows that medication used to treat ADHD in adult men can save lives on the road.