Παρασκευή, 25 Απριλίου 2014

ScienceDaily: Latest Science News

ScienceDaily: Latest Science News


Microscopic organism plays a big role in ocean carbon cycling

Posted: 24 Apr 2014 12:18 PM PDT

Scientists have taken a leap forward in understanding the microscopic underpinnings of the ocean carbon cycle by pinpointing a bacterium that appears to play a dominant role in carbon consumption.

Genomic diversity and admixture differs for stone-age Scandinavian foragers and farmers

Posted: 24 Apr 2014 12:18 PM PDT

Scientists report a breakthrough on understanding the demographic history of Stone-Age humans. A genomic analysis of eleven Stone-Age human remains from Scandinavia revealed that expanding Stone-age farmers assimilated local hunter-gatherers, and that the hunter-gatherers were historically in lower numbers than the farmers. The transition between a hunting-gathering lifestyle and a farming lifestyle has been debated for a century. As scientists learned to work with DNA from ancient human material, a complete new way to learn about the people in that period opened up.

Some corals adjusting to rising ocean temperatures

Posted: 24 Apr 2014 11:37 AM PDT

Scientists have revealed how some corals can quickly switch on or off certain genes in order to survive in warmer-than-average tidal waters. To most people, 86-degree Fahrenheit water is pleasant for bathing and swimming. To most sea creatures, however, it's deadly. As climate change heats up ocean temperatures, the future of species such as coral, which provides sustenance and livelihoods to a billion people, is threatened.

Cosmic illusion revealed: Gravitational lens magnifies supernova

Posted: 24 Apr 2014 11:36 AM PDT

Astronomers have announced the discovery of a galaxy that magnified a background, Type Ia supernova thirty-fold through gravitational lensing. This first example of strong gravitational lensing of a supernova confirms the team's previous explanation for the unusual properties of this supernova.

Ocean microbes display remarkable genetic diversity: One species, a few drops of seawater, hundreds of coexisting subpopulations

Posted: 24 Apr 2014 11:36 AM PDT

The smallest, most abundant marine microbe, Prochlorococcus, is a photosynthetic bacteria species essential to the marine ecosystem. An estimated billion billion billion of the single-cell creatures live in the oceans, forming the base of the marine food chain and occupying a range of ecological niches based on temperature, light and chemical preferences, and interactions with other species. But the full extent and characteristics of diversity within this single species remains a puzzle.

Breakthrough harnesses light for controlled chemical reaction

Posted: 24 Apr 2014 11:36 AM PDT

One catalyst supplies electrons, other one controls position of raw material. Reactions are powered by visible light, not UV. Technique could allow creation of novel molecules for pharmaceuticals.

Preserving endangered Middle East cultures, including early Christian

Posted: 24 Apr 2014 11:34 AM PDT

The cultural heritage of Syriac, an important language in the spread of early Christianity in the Middle East, is being preserved through the international collaboration.

Genome yields insights into golden eagle vision, smell

Posted: 24 Apr 2014 11:10 AM PDT

Scientists have sequenced the genome of the golden eagle, providing a bird's-eye view of eagle features that could lead to more effective conservation strategies.

Tsetse fly genome reveals weaknesses: International 10-year project unravels biology of disease-causing fly

Posted: 24 Apr 2014 11:09 AM PDT

Mining the genome of the disease-transmitting tsetse fly, researchers have revealed the genetic adaptions that allow it to have such unique biology and transmit disease to both humans and animals. The tsetse fly spreads the parasitic diseases human African trypanosomiasis, known as sleeping sickness, and Nagana that infect humans and animals respectively. Throughout sub-Saharan Africa, 70 million people are currently at risk of deadly infection.

Astronomical forensics uncover planetary disks in NASA's Hubble archive

Posted: 24 Apr 2014 11:09 AM PDT

Astronomers using NASA's Hubble Space Telescope have applied a new image processing technique to obtain near-infrared scattered light photos of five disks observed around young stars in the Mikulski Archive for Space Telescopes database. These disks are telltale evidence for newly formed planets.

Carbon loss from soil accelerating climate change

Posted: 24 Apr 2014 11:09 AM PDT

New research has found that increased levels of carbon dioxide in the atmosphere cause soil microbes to produce more carbon dioxide, accelerating climate change. This research challenges our previous understanding about how carbon accumulates in soil.

Scientists build new 'off switch' to shut down neural activity

Posted: 24 Apr 2014 11:09 AM PDT

Nearly a decade ago, the era of optogenetics was ushered in with the development of channelrhodopsins, light-activated ion channels that can, with the flick of a switch, instantaneously turn on neurons in which they are genetically expressed. What has lagged behind, however, is the ability to use light to inactivate neurons with an equal level of reliability and efficiency. Now, scientists have used an analysis of channelrhodopsin's molecular structure to guide a series of genetic mutations to the ion channel that grant the power to silence neurons with an unprecedented level of control.

You may have billions and billions of good reasons for being unfit

Posted: 24 Apr 2014 11:09 AM PDT

Although our chromosomes are relatively stable within our lifetimes, the genetic material found in our mitochondria is highly variable across individuals and may impact upon human health, say researchers. Genomes are changing, not just from generation to generation, but even and in fact within our individual cells. The researchers are the first to identify the extent to which the editing processes of RNA code can vary across a large number of individuals.

Why does breast cancer often spread to the lung? Experts explain

Posted: 24 Apr 2014 09:53 AM PDT

New research shows why breast cancer often spreads or metastasizes to the lung. The breast cancer stem cell (CSC) has been shown to be responsible for metastasis in animal models, particularly to the lung. And this new research found CSCs have a particular propensity for migrating towards and growing in the lung because of certain proteins found there.

Cell resiliency surprises scientists

Posted: 24 Apr 2014 09:52 AM PDT

Cells are more resilient in taking care of their DNA than scientists originally thought, new research shows. Even when missing critical components, cells can adapt and make copies of their DNA in an alternative way. In a new study, a team of researchers showed that cells can grow normally without a crucial component needed to duplicate their DNA.

Skin layer grown from human stem cells could replace animals in drug, cosmetics testing

Posted: 24 Apr 2014 09:52 AM PDT

The first lab-grown epidermis -- the outermost skin layer -- with a functional permeability barrier akin to real skin has been developed by scientists. The new epidermis, grown from human pluripotent stem cells, offers a cost-effective alternative lab model for testing drugs and cosmetics, and could also help to develop new therapies for rare and common skin disorders.

Large-scale identification, analysis of suppressive drug interactions

Posted: 24 Apr 2014 09:52 AM PDT

Cell analysis finds drug interactions to be startlingly common: baker's yeast is giving scientists a better understanding of drug interactions, which are a major cause of illness and hospitalization worldwide. When two or more medications are taken at the same time, one can suppress or enhance the effectiveness of the other. Similarly, one drug may magnify the toxicity of another. There are severe practical limits on the practical scope of drug studies in humans. Limits come in part from ethics and in part from the staggering expense.

Blood cells reprogrammed into blood stem cells in mice

Posted: 24 Apr 2014 09:52 AM PDT

Researchers have reprogrammed mature blood cells from mice into blood-forming hematopoietic stem cells, using a cocktail of eight genetic switches called transcription factors. The reprogrammed cells are able to self-renew like HSCs and can give rise to all of the cellular components of the blood like HSCs. The findings mark a significant step toward a major goal of regenerative medicine: the ability to produce HSCs suitable for hematopoietic stem cell transplantation from other cell types.

New genetic brain disorder in humans discovered

Posted: 24 Apr 2014 09:51 AM PDT

A newly identified genetic disorder associated with degeneration of the central and peripheral nervous systems in humans, along with the genetic cause, has been reported by researchers. By performing DNA sequencing of more than 4,000 families affected by neurological problems, the two research teams independently discovered that a disease marked by reduced brain size and sensory and motor defects is caused by a mutation in a gene called CLP1, which is known to regulate tRNA metabolism in cells.

New type of protein action found to regulate development

Posted: 24 Apr 2014 09:51 AM PDT

Researchers report they have figured out how the aptly named protein Botch blocks the signaling protein called Notch, which helps regulate development. In a report on the discovery, the scientists say they expect the work to lead to a better understanding of how a single protein, Notch, directs actions needed for the healthy development of organs as diverse as brains and kidneys.

Oxygen diminishes heart's ability to regenerate, researchers discover

Posted: 24 Apr 2014 09:49 AM PDT

Scientific research previously discovered that the newborn animal heart can heal itself completely, whereas the adult heart lacks this ability. New research by the same team today has revealed why the heart loses its incredible regenerative capability in adulthood, and the answer is quite simple -- oxygen.

New point of attack on HIV for vaccine development

Posted: 24 Apr 2014 09:47 AM PDT

A new vulnerable site on the HIV virus has been found, which may lead researchers closer to developing a vaccine for the illness. "HIV has very few known sites of vulnerability, but in this work we've described a new one, and we expect it will be useful in developing a vaccine," said one researcher.

Fruitfly study identifies brain circuit that drives daily cycles of rest, activity

Posted: 24 Apr 2014 09:46 AM PDT

Researchers describe a circuit in the brain of fruit flies that controls their daily, rhythmic behavior of rest and activity. They also found that the fly version of the human brain protein known as corticotrophin releasing factor is a major coordinating molecule in this circuit.

Oldest pterodactyloid species discovered: Primitive flying reptile took wing 163 million years ago

Posted: 24 Apr 2014 09:46 AM PDT

Scientists have discovered and named the earliest and most primitive pterodactyloid -- a group of flying reptiles that would go on to become the largest known flying creatures to have ever existed -- and established they flew above Earth some 163 million years ago, longer than previously known.

'Double-duty' electrolyte enables new chemistry for longer-lived batteries

Posted: 24 Apr 2014 08:33 AM PDT

Researchers have developed a new and unconventional battery chemistry aimed at producing batteries that last longer than previously thought possible. Researchers have challenged a long-held assumption that a battery's three main components -- the positive cathode, negative anode and ion-conducting electrolyte -- can play only one role in the device.

Small business owners not always worried about being treated fairly, researcher finds

Posted: 24 Apr 2014 08:33 AM PDT

Fairness is not always the most important priority for small retailers. In an international study, researchers found that some small retailers are less concerned about whether they are treated fairly by business suppliers than other factors, such as cash flow and company survival. "It is presumed that fairness, however it is defined by individual businesses, is important to all businesses," one researcher said. "Our research challenges that presumption and reveals that the importance placed on fairness can vary greatly among retailers."

The blood preserved in the preserved relic pumpkin did not belong to Louis XVI

Posted: 24 Apr 2014 08:33 AM PDT

The results of an international study indicate that the DNA recovered from the inside of a pumpkin, attributed so far to the French King Louis XVI, does not actually belong to the monarch, guillotined in 1793. Complete genome sequencing suggests that blood remains correspond to a male with brown eyes, instead of blue as Louis XVI had, and shorter.

Spiders in space weave a web of scientific inspiration for Spider-Man fans

Posted: 24 Apr 2014 08:30 AM PDT

While spiders were busy spinning webs in space, researchers on Earth weaved their knowledge of this activity into educational materials to inspire and motivate students. Now, this free, Web-based guide is being re-released through Scholastic and Sony Pictures as curriculum for educators to leap on the excitement surrounding the release of the film, "The Amazing Spider-Man 2."

'Tis the season: Be on the lookout for brown recluse spiders

Posted: 24 Apr 2014 08:27 AM PDT

Warmer, spring weather has many of us getting out and becoming more active, and the brown recluse spider is no exception. Scientists shared 10 facts about the somewhat small, shy spider.

Paying closer attention to attention

Posted: 24 Apr 2014 08:27 AM PDT

There may be an overreporting of attention problems in children with fetal alcohol spectrum disorder (FASD), simply because parents and teachers are using a misplaced basis for comparison. They are testing and comparing children with FASD with children of the same physical or chronological age, rather than with children of the same mental age, which is often quite a lot younger.

Equipped with new sensors, Morpheus preps to tackle landing on its own

Posted: 24 Apr 2014 08:27 AM PDT

A test flight later this week will challenge a set of sensors to map out a 65-yard square of boulder-sized hazards and pick out a safe place to land. Mounted to an uncrewed prototype lander called Morpheus that flies autonomously several hundred feet above the ground, the sensor system will have 10 seconds to do its work: six seconds really, as it will take four seconds to map the area before choosing a landing site. The sensor system is a 400-pound set of computers and three instruments called ALHAT, short for Autonomous Landing and Hazard Avoidance Technology.

Take the bat, leave the candy: The food environment of youth baseball

Posted: 24 Apr 2014 08:27 AM PDT

"Take me out to the ballgame" doesn't exactly conjure up images of apple slices and kale chips. The more likely culprits include French fries, soda and the occasional box of Crackerjacks. Unfortunately for children who play youth baseball, eating unhealthy food during practices and games may be contributing to weight problems, according to researchers.

NASA aeronautics set to premiere high-flying sequel

Posted: 24 Apr 2014 08:22 AM PDT

For the second time in as many years, NASA researchers beginning in early May will take to the skies with a DC-8 and other aircraft to conduct a series of flight tests designed to study the effects on emissions and contrail formation of burning alternative fuels in jet engines. This year's Alternative Fuel Effects on Contrails and Cruise Emissions flight tests, known as ACCESS II for short, will feature new science instruments and new flight profiles to follow.

A step up for NASA’s robonaut: Ready for climbing legs

Posted: 24 Apr 2014 08:20 AM PDT

Getting your "space legs" in Earth orbit has taken on new meaning for NASA's pioneering Robonaut program. Thanks to a successful launch of the SpaceX-3 flight of the Falcon 9/Dragon capsule on Friday, April 18, the lower limbs for Robonaut 2 (R2) are aboard the International Space Station (ISS). Safely tucked inside the Dragon resupply vehicle, R2's legs are to be attached by a station crew member to Robonaut's torso already on the orbiting outpost.

NASA tests Orion’s parachute performance over Arizona while work progresses in Florida

Posted: 24 Apr 2014 08:18 AM PDT

The team designing the parachute system for NASA's Orion spacecraft has demonstrated almost every parachute failure they could imagine. But on April 23, they tested how the system would perform if the failure wasn't in the parachutes.

Your T-shirt's ringing: Printable tiny flexible cell phones for clothes?

Posted: 24 Apr 2014 07:28 AM PDT

A new version of 'spaser' technology being investigated could mean that mobile phones become so small, efficient, and flexible they could be printed on clothing. A spaser is effectively a nanoscale laser or nanolaser. It emits a beam of light through the vibration of free electrons, rather than the space-consuming electromagnetic wave emission process of a traditional laser.

Take notes by hand for better long-term comprehension

Posted: 24 Apr 2014 07:28 AM PDT

Dust off those Bic ballpoints and college-ruled notebooks: research shows that taking notes by hand is better than taking notes on a laptop for remembering conceptual information over the long term. "Our new findings suggest that even when laptops are used as intended -- and not for buying things on Amazon during class -- they may still be harming academic performance," says a psychological scientist involved in the study.

Leaders call for expanded use of medications to combat opioid overdose epidemic

Posted: 24 Apr 2014 07:28 AM PDT

A national response to the epidemic of prescription opioid overdose deaths was outlined by leaders of agencies in the U.S. Department of Health and Human Services. The commentary calls upon health care providers to expand their use of medications to treat opioid addiction and reduce overdose deaths, and describes a number of misperceptions that have limited access to these potentially life-saving medications.

Using antineutrinos to monitor nuclear reactors

Posted: 24 Apr 2014 07:28 AM PDT

When monitoring nuclear reactors, the International Atomic Energy Agency has to rely on input given by the operators. In the future, antineutrino detectors may provide an additional option for monitoring. However, heretofore the cumulative antineutrino spectrum of uranium 238 fission products was missing. Physicists have now closed this gap using fast neutrons.

Bake your own droplet lens: Cheap, high-quality lenses made from droplets of transparent silicone

Posted: 24 Apr 2014 07:28 AM PDT

Researchers have created a new type of lens that costs less than a penny to make, and can be used in a 3-D printed attachment that turns a Smartphone into a dermascope, a tool to diagnose skin diseases like melanoma. Normal dermascopes can cost $500 or more, but this version costs a mere $2 and is slated to be commercially available in just a few months.

New ultrasound device may add in detecting risk for heart attack, stroke

Posted: 24 Apr 2014 07:26 AM PDT

A new ultrasound device that could help identify arterial plaque that is at high risk of breaking off and causing heart attack or stroke has been developed by researchers. The prototype device has performed well in laboratory testing, but the researchers say they are continuing to optimize the technology. They hope to launch pre-clinical studies in the near future.

Hydrothermal vents: How productive are the ore factories in the deep sea?

Posted: 24 Apr 2014 07:26 AM PDT

Hydrothermal vents in the deep sea, the so-called 'black smokers,' are fascinating geological formations. They are home to unique ecosystems, but are also potential suppliers of raw materials for the future. They are driven by volcanic 'power plants' in the seafloor. But how exactly do they extract their energy from the volcanic rock?

Palliation is rarely a topic in studies on advanced cancer

Posted: 24 Apr 2014 07:24 AM PDT

Randomized controlled trials only rarely consider end-of-life aspects and often fail to name superordinate patient-relevant treatment goals. Instead of quality of life, survival is in the foreground, research shows.

Boring cells could hold the key to heart disease

Posted: 24 Apr 2014 07:24 AM PDT

Fibroblasts, cells long thought to be boring and irrelevant, could offer an alternative to heart transplants for patients with heart disease. "Heart disease is still one of the major killers in our society and so far no effective therapeutic options are available. Our laboratory aims to understand how the various cell types present in a heart can improve the outcome of heart failure,' said the lead researcher.

Motor skill deficiencies linked to autism severity, reseearch says

Posted: 24 Apr 2014 07:24 AM PDT

A relationship between motor skill deficiencies and the severity of the symptoms of autism spectrum disorder has been found in very young children. The findings indicate that development of motor skills should be included in treatment plans for young children with autism. Most autism treatment plans for young children focus on social communication because the disability has such a significant effect in that area. Incorporating fine and gross motor skill development into early interventions could provide a similar boost, the researchers say.

When things get glassy, molecules go fractal

Posted: 24 Apr 2014 07:24 AM PDT

School children learn the difference between liquids and gases, but centuries of scholarship have failed to produce consensus about how to categorize glass. Now, combining theory and numerical simulations, researchers have resolved an enduring question in the theory of glasses, showing that their energy landscapes are far rougher than previously believed. The new model shows that molecules in glassy materials settle into a fractal hierarchy of states.

Critical vulnerabilities in TLS implementation for Java

Posted: 24 Apr 2014 07:23 AM PDT

In January and April 2014, Oracle has released critical Java software security updates. They resolve vulnerabilities that affected the "Java Secure Socket Extension" (JSSE), a software library implementing the "Transport Layer Security" protocol (TLS). TLS is used to encrypt sensitive information transferred between browsers and web servers, such as passwords and credit card data, for example.

How do liquid foams completely block sound?

Posted: 24 Apr 2014 07:22 AM PDT

Liquid foams have a remarkable property: they completely block the transmission of sound over a wide range of frequencies. Physicists have studied how sound is attenuated in liquid foams. Their findings open the way to the development of tools called acoustic probes that could be used to monitor the quality of foams used in industry, especially in the mining and petroleum sectors.

Asteroids made easy: 'Patch of asteroid' being built inside a satellite

Posted: 24 Apr 2014 07:21 AM PDT

A dozen astronauts have walked on the moon, and several rovers have been piloted on Mars, giving us a good understanding of these off-world environments. But when it comes to asteroids, scientists enter uncharted territory. Landing on an asteroid is notoriously difficult. Scientists are now looking to mitigate risk involved in landing on an asteroid by building a "patch of asteroid" inside of a small, spinning satellite.

Virtual artificial heart implantation: Advances made by scientists

Posted: 24 Apr 2014 07:21 AM PDT

The first virtual implantation of a pioneering artificial heart has been performed. The artificial heart was implanted into an undersized adolescent, and supported the boy for 11 days before he underwent a heart transplant. "3-D heart models and performance of virtual heart implantations are no longer the inventions of science fiction. They are happening and they are impacting medicine, medical education and quality of life right now," one expert says.

How a plant beckons bacteria that will do it harm

Posted: 24 Apr 2014 07:20 AM PDT

A common plant puts out a welcome mat to bacteria seeking to invade, and scientists have discovered the mat's molecular mix. The team showed that the humble and oft-studied plant Arabidopsis puts out a molecular signal that invites an attack from a pathogen. The study reveals new targets during the battle between microbe and host.

Two new river turtle species described

Posted: 24 Apr 2014 07:20 AM PDT

The alligator snapping turtle is the largest river turtle in North America, weighing in at up to 200 pounds and living almost a century. Now researchers have discovered that it is not one species -- but three. By examining museum specimens and wild turtles, the scientists uncovered deep evolutionary divisions in this ancient reptile.

It's a bubble, but not as we know it

Posted: 23 Apr 2014 07:16 PM PDT

Multi-sensory technology that creates soap bubbles, which can have images projected onto them or when the bubbles are burst release a scent, is being unveiled at an international conference. The research could be used in areas such as gaming or education and encourage a new way of thinking about multi-sensory technologies.

Microbes provide insights into evolution of human language

Posted: 23 Apr 2014 07:14 PM PDT

Research into Pseudomonas aeruginosa, a type of bacteria common in water and soil, shows that they can communicate in a way that was previously thought to be unique to humans and perhaps some other primates. The bacteria used combinatorial communication, in which two signals are used together to achieve an effect that is different to the sum of the effects of the component parts.

Genetics explain why some kids are bigger than others

Posted: 23 Apr 2014 07:14 PM PDT

The influence of genetic factors on differences between children's Body Mass Index increases from 43 percent at age four to 82 percent at age 10, reports a new study. The researchers studied 2,556 pairs of twins from the Twins Early Development Study. Data were collected in England and Wales in 1999 and 2005 when the twins were four and 10 years old respectively.

'Off-the-shelf' equipment used to digitize insects in 3-D: Model insects useful for studying, sharing specimens

Posted: 23 Apr 2014 07:14 PM PDT

Scientists have developed a cost-effective, off-the-shelf system to obtain natural-color 3-D models of insects. Scientists studying insects rely on collected specimens that are often shared between scientists through written descriptions, diagrams, and images. These 2D tools are important in understanding and sharing specimens, but they often lack the precise detail of the actual 3D specimen. The authors of this study, interested in understanding the feasibility of digitizing insects for research purposes, created a cost-effective prototype to produce 3D naturally colored digital models of medium-to-large insects (3 to 30mm in length), using off-the-shelf equipment and software.

Citizen scientists match research tool when counting sharks: Dive guides monitoring sharks on coral reef at similar level to telemetry

Posted: 23 Apr 2014 07:14 PM PDT

Shark data collected by citizen scientists may be as reliable as data collected using automated tools. Shark populations are declining globally, and scientists lack data to estimate the conservation status of populations for many shark species. Citizen science may be a useful and cost-effective means to increase knowledge of shark populations on coral reefs, but scientists do not yet know enough about how data collected by untrained observers compares to results from traditional research methods. To better understand the reliability of datasets collected by citizen science initiatives, researchers in this study compared reef shark sightings counted by experienced dive guides (citizen scientists), with data collected from tagged reef sharks by an automated tracking tool (acoustic telemetry).

Luck affects how we judge reckless actions

Posted: 23 Apr 2014 07:12 PM PDT

A person, who acts immorally or recklessly but is "lucky" by escaping dire consequences, is judged less harshly than an "unlucky" person, even when both have committed the same act. "Moral luck" is a term used in philosophy that describes situations in which a person is subjected to moral judgments by others despite the fact that the assessment is based on factors beyond his or her control, i.e. "luck."

Vitamin D supplements have little effect on risk of falls in older people

Posted: 23 Apr 2014 07:12 PM PDT

A new meta-analysis concludes that there is no evidence to suggest that vitamin D supplements prevent falls, and that ongoing trials to test this theory are unlikely to change this result. Falls can be devastating for older people, and strategies to reduce fall risk are urgently needed as the global population ages. The results of trials that have investigated the ability of vitamin D to prevent falls -- and those of previous meta-analyses -- have been mixed. It is unclear how vitamin D supplements might prevent falls but, until now.

Recurrent violence linked to substantially higher rates of mental disorders in post-conflict communities

Posted: 23 Apr 2014 07:12 PM PDT

In the aftermath of war, communities who continue to experience repeated violence could have a major escalation in rates of post-traumatic stress disorder (PTSD) and severe distress, suggests new research. Investigators conducted a survey in 2004 to estimate the prevalence of common mental disorders among 1022 adults in Timor Leste four years after the end of a long-running and violent war against Indonesian occupation, and again in 2010–11, following a period of prolonged internal conflict.

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