#Nearby star is almost as old as the Universe Astronomers have discovered a Methuselah of stars#a denizen of the Solar system's neighbourhood that is at least 13.2 billion years old and formed shortly after the Big bang."
says Howard Bond, an astronomer at Pennsylvania State university in University Park, who announced the finding on 10 january at a meeting of the American Astronomical Society in Long beach, California1.
First, Bond and his team made a new and more accurate determination of the star s distance from the Solar system,
using 11 sets of observations recorded between 2003 and 2011 using the Hubble space telescope s Fine Guidance Sensors,
which it is exhausting the hydrogen at its core. In this phase, the star's slowly dimming luminosity is a highly sensitive indicator of its age,
says Bond. His team calculates that the star is 13.9 billion years old, give or take 700 million years.
says Bond. The discovery places constraints on early star formation, says Volker Bromm, an astronomer at the University of Texas at Austin.
The very first generation of stars coalesced from primordial gas, which did not contain appreciable amounts of elements heavier than helium,
#Electron beams set nanostructures aglow Put a piece of quartz under an electron microscope and it will shine an icy blue.
First noticed in the 1960s, the phenomenon, called cathodoluminescence, gave geologists an easy way to identify quartz and other minerals in rock samples.
turning the glow into a precise probe of a material s nanoscale structure. The researchers expect the technology to reach the market early this year,
giving materials scientists a new tool for investigating the behaviour of light in the interiors of the complex nanostructures used in lasers, light-based circuits and solar cells."
An electron beam can in principle achieve a resolution of less than one nanometre, compared with hundreds of nanometres for a beam of light.
But maps made by scattered or reflected electrons are not typically sensitive to the way light behaves in the sample.
it promises the same nanometre scale resolution that those systems can achieve.""This has opened the door to understanding how light couples to matter in a more fundamental way,
and energy of the light (see Metamaterial TV). The device is sensitive enough to pick up a signal even from materials that are barely luminescent, such as metals.
Just as in an old-fashioned cathode ray tube-tube colour television, the electron beam scans the sample to build up an image line by line.
Source: Ernst Jan Vesseur & Toon Coenen (Amolf) Already, the Dutch group, along with collaborators in the United states and Spain, has used the technique to tease out how certain nanostructures interact with light.
In a recent paper studying a layered construct of silver, glass and silicon, they show that the phase velocity of visible light#the speed at which the peaks
and troughs of the wave travel through the material#is so fast that it is travelling effectively in a vacuum, the explanation for the material s overall refractive index of zero (E.#J.#R.#Vesseur et al.
The effect had been predicted in such layered structures, called metamaterials, but observing it required a higher-resolution map of light emission than earlier techniques could produce.
The team has mapped also the distribution of light in the silicon nanodiscs that are used as a coating on solar cells to improve efficiency,
and in the ultra-small cavities of photonic crystals#components of chip-based lasers and light-emitting diodes."
Lukas Novotny, an optical physicist at The swiss Federal Institute of technology in Zurich, says that cathodoluminescence could be a useful tool for improving the performance of light-emitting devices and solar cells,
and Polman says that the company will soon be selling the devices to materials researchers in universities for between US$100, 000 and $200, 000;
later it may target the laser, semiconductor and solar-cell industries. He realizes that, by selling the system,
four health scientists accused of research misconduct are expected to file into a room at Saint louis University in Missouri to conduct an experiment:
With the rapid growth of misconduct cases, some scientists are worried that preventative training in research ethics might not be enough.
says James Dubois, an ethicist at Saint louis University, who leads the rehab programme, called Repair (Restoring Professionalism and Integrity in Research)."
Wright puts much of this down to software that has made it easier for watchdogs to detect possible plagiarism or image manipulation in publications."
Lauran Qualkenbush, director of the research-integrity office at Northwestern University in Chicago, says that there is a gap between harsh penalties for misconduct#such as bans from receiving government funding
"These are people we feel could be valuable members of our faculty and community. Dubois aims to fill that gap.
Although remedial courses have been available for physicians for more than a decade#with many returning to medicine to forge successful careers#Dubois says that Repair is the first such programme for researchers.
around six universities, including Northwestern, have signed up as partners in the programme. Some ethicists are unsure how effective such rehab will be.
Nicholas Steneck, an ethicist at the University of Michigan in Ann arbor, is broadly supportive of the goals of Repair,
if the money might be spent better on measures that prevent misconduct. Although the ORI is not endorsing Repair specifically
such as failing to disclose a conflict of interest.""What do you do with them to make them whole as members of the research community,
if Dubois and colleagues programme will work, but thinks that it is"a worthy effort and
a London-based company that provides training on research integrity, that is because the definition of misconduct is broadening beyond falsification, fabrication and plagiarism.
#High court ensures continued US funding of human embryonic-stem-cell research The US Supreme court today ended an effort to shut down government support of human embryonic-stem-cell research,
by refusing to hear a case that challenged the legality of funding for the work by the National institutes of health (NIH).
to stop NIH backing of the work, which holds the promise of treatments for a variety of diseases,
but which depends on the destruction of days-old human embryos. As is typical practice, the court did not give reasons for declining to hear the case.
But the lead plaintiff on the case, James Sherley of the Boston Biomedical Research Institute in Watertown, Massachusetts, says that the decision will not end his efforts"to emancipate human embryos from research slavery sponsored by the NIH.
It was in August 2009, that Sherley and Theresa Deisher, the chief executive of AVM Biotechnology in Seattle,
and led to scores of new human embryonic-stem-cell lines being available to NIH-funded researchers.
from leftover embryos at fertility clinics that would have been thrown away. The NIH does not fund the derivation of the lines, only the subsequent research.
saying that work on embryonic-stem-cell lines could lead to therapies for Parkinson s disease, diabetes and other ailments."
"What a great day for science, says Amy Comstock Rick, president of the Coalition for the Advancement of Medical Research in WASHINGTON DC, an umbrella group of organizations that advocate for the research.
"The ruling erases the nagging worry that existing funding could be cut off at any time.
#Flesh-eating flies map forest biodiversity The blowflies and flesh flies that settle on dead animals aren't just feasting on the carrion#they're sampling their DNA.
providing a quick and cost-effective snapshot of mammal diversity in otherwise inaccessible rainforests. Researchers stumbled on the grisly cataloguing technique while studying a form of anthrax that kills chimpanzees in C# te d'Ivoire.
They started sampling flies to see whether the insects could harbour the anthrax bacterium after feasting on infected bodies,
but soon realized"that detecting mammal DNA from flies could also be an extremely cool tool for assessing biodiversity,
says team leader S#bastien Calvignac-Spencer, an evolutionary biologist at the Robert Koch Institute in Berlin.#
#By baiting nets and traps with meat, the team collected carrion flies from Ta#National park in C# te d'Ivoire and Kirindy Reserve in Madagascar,
and found that 40%of them carried mammal DNA. The researchers sequenced this material to identify 16 mammals in C# te d'Ivoire,
including six of the nine local primate species, as well as Jentink s duiker (Cephalophus jentinki)# an endangered antelope of which fewer than 3, 500 remain.
The work will appear on 7 january in Molecular Ecology1. The DNA is"not gorgeous but still usable, says Calvignac-Spencer:
a geneticist at the University of Copenhagen who last year showed3 that leeches can also preserve the DNA of the animals they feed on.
Carl Agee of the University of New mexico in Albuquerque and his colleagues report their findings from samples of the meteorite in Science online today1."
notes Harry Mcsween at the University of Tennessee in Knoxville. The meteorite is made of volcanic rock,
But Jeffrey Taylor of the University of Hawaii in Honolulu says that whether that water content truly reveals an abundance of surface water on Mars 2. 1 billion years ago awaits further study u
Physicists later realized that the absolute temperature of a gas is related to the average energy of its particles.
which particles have no energy at all, and higher temperatures correspond to higher average energies. However, by the 1950s, physicists working with more exotic systems began to realise that this isn't always true:
Technically, you read off the temperature of a system from a graph that plots the probabilities of its particles being found with certain energies.
Normally, most particles have average or near-average energies, with only a few particles zipping around at higher energies.
In theory, if the situation is reversed, with more particles having higher, rather than lower energies, the plot would flip over
explains Ulrich Schneider, a physicist at the Ludwig Maximilian University in Munich, Germany. Schneider and his colleagues reached such sub-absolute-zero temperatures with an ultracold quantum gas made up of potassium atoms.
Using lasers and magnetic fields they kept the individual atoms in a lattice arrangement. At positive temperatures, the atoms repel,
The team then quickly adjusted the magnetic fields, causing the atoms to attract rather than repel each other."
lowest-energy state to the highest possible energy state, before they can react, says Schneider."
calls the latest work an"experimental tour de force. Exotic high-energy states that are hard to generate in the laboratory at positive temperatures become stable at negative absolute temperatures#"as
though you can stand a pyramid on its head and not worry about it toppling over,
says Achim Rosch, a theoretical physicist at the University of Cologne in Germany, who proposed the technique used by Schneider and his team3.
-),started building in 2006, when Todd Sacktor at the SUNY Downstate Medical center in New york city wiped out established spatial memories in rats.
He did so by injecting their brains with ZIP, a small peptide that is meant to block the enzyme1.
but was concerned that much of the data depended on the actions of ZIP. He and his collaborators took a different route,
Working independently, Robert Messing and colleagues at the University of California, San francisco, created similar mice5.
Messing s animals formed persistent memories for fears, objects, places and movements across a battery of behavioral tests.
And Huganir s mice showed normal levels of long-term potentiation#the strengthening of synapses between two neurons that is thought to underlie learning and memory."
but it is not the essential master regulator of memory that the current literature suggests it to be,
"I think the future will be to try to find the backup mechanisms for memory. However, Huganir s team also created mice whose PKM?
says Lynn Nadel, a cognitive scientist at the University of Arizona in Tucson.""But they show that the situation is complicated#surprise!#
#US fiscal deal leaves science vulnerable Law-makers in WASHINGTON DC greeted the new year with a frantic deal meant to avert a fiscal crisis
and the House in pre-dawn votes on 1 and 2 january keeps researchers on tenterhooks for at least another two months by delaying mandatory spending cuts that could threaten science funding.
but could push the country s weak economy back into recession. The cuts, known as the sequester,
Rancorous last-minute negotiations yielded a tenuous agreement to raise taxes for the wealthy, but deferred decisions on the sequester#an across-the-board reduction of about 8%in nondefence discretionary spending, with at least 9%carved from defence#by two months."
"But it does give advocates more time to convince policy-makers that cutting the US investment in R&d is counterproductive.
in case there is a sudden plunge in government funding. Nancy Andrews, dean of the Duke university School of medicine in Durham, North carolina, says that the medical school may need to cut back on graduate admissions,
freeze salaries and reduce faculty recruitments if the NIH takes a severe hit.""The bill isn t ideal.
But it does give advocates more time to convince policy-makers that cutting US investment in R&d is counter#productive.
The two-month delay to the sequester is a complication for Andrews, who is wrestling with decisions on faculty retention
and recruitment that must be made by Mid-january.""If we need to spend more to help current faculty members maintain their research programmes through funding gaps,
it will be harder to provide start-up funding for new faculty members, she says. The delay means that law-makers will debate the sequester at the same time as they tackle the overall federal budget.
The US Congress s inability to agree on a 2013 budget last year led it to adopt a continuing resolution that allows the government to keep functioning at roughly 2012 funding levels.
That resolution expires on 27 march. By then, the country will also have reached a cap on the amount of money that it can borrow.
This timing may increase the momentum behind big spending cuts cautions Michael Lubell, director of public affairs for the American Physical Society in WASHINGTON DC.
an implant records its brain activity and signals to a similar device in the brain of a rat in the United states. The US rat then usually makes the same choice on the same task.
Nicolelis says that the work, published today in Scientific Reports1, is the first step towards constructing an organic computer that uses networks of linked animal brains to solve tasks.
But other scientists who work on neural implants are sceptical. Lee Miller, a physiologist at Northwestern University in Evanston, Illinois, says that Nicolelis s team has made many important contributions to neural interfaces,
but the current paper could be mistaken for a"poor Hollywood science-fiction script. He adds, "It is not clear to
what end the effort is really being made. In earlier work2 Nicolelis s team developed implants that can send
and receive signals from the brain, allowing monkeys to control robotic or virtual arms and get a sense of touch in return.
whether he could use these implants to couple the brains of two separate animals. His colleague Miguel Pais-Vieira started by training one rat#the encoder#to press one of two levers,
as indicated by a light. An implant recorded neural activity in the rat's motor cortex (the area that controls its movements), compared it to earlier recordings,
and converted it into a simpler signal: a single pulse representing one lever, or a train of them representing the other.
and implants linked their somatosensory cortices, the regions involved in touch. This link worked even
and the other in the Duke lab.#But Andrew Schwartz, a neurobiologist at the University of Pittsburgh in Pennsylvania, notes that the decoders performed poorly,
from creating organic computers to uniting different parts of the same brain that have been cut off by damage or disease.
a neuroscientist from the University of Chicago in Illinois, says that if the goal is to make better neural prosthetics,
And if it is to build a computer, "the proposition is speculative and the evidence underwhelming.
which paired individuals control virtual avatars and combine their brain activity to play a game together."
electrically charged particles, corralled into separate doughnut-shaped rings by Earth s magnetic field. The outer ring orbits at a distance of some 10,000-60,000 kilometres above Earth,
when James Van allen first spotted them using satellite data half a century ago, and that s also the structure that NASA s twin Van allen Probes recorded
says Daniel Baker, a space physicist at the University of Colorado in Boulder.##The new ring persisted,
Baker goes on to say that data collected by the probes on 9 october revealed that"suddenly the whole outer belt was lit up again but with the middle ring gone.
and numerical modellers all over the world, says Yuri Shprits, a geophysicist at the University of California, Los angeles,
#Liquid storage could make hydrogen a feasible fuel A process for extracting hydrogen from a liquid fuel could remove one of the biggest hurdles to a'hydrogen economy,
They have developed a catalyst that harvests the gas from methanol, a liquid fuel that#unlike hydrogen itself#can be transported easily
Matthias Beller, a chemical engineer at the University of Rostock in Germany, and his colleagues hope that methanol might one day be sluiced through pipelines
before chemical reactions convert the liquid back to hydrogen where it is needed#for example to provide power to off-grid villages,
or run cars or mobile devices. Hydrogen has a high energy density and is completely clean, burning to leave behind only water vapour as waste.
It cannot be mined in large amounts, but proponents of a hydrogen economy say that it could be produced in vast quantities from water using excess electricity from wind turbines and solar plants.
Unfortunately, because hydrogen is a gas it is difficult to store and transport safely unless compressed or liquefied,
which is cumbersome and takes a lot of energy. Many chemists have spent decades studying how best to trap hydrogen for use as a fuel.
Locking the gas up in the form of solid or liquid chemicals is one answer. Many materials proposed for hydrogen storage
or hold onto the hydrogen so tightly that it takes an unfeasible amount of energy to retrieve.
a well-known reaction combines hydrogen and carbon monoxide gases using commercial catalysts. Methanol also traps a lot of hydrogen (12.5%by weight.
It is difficult to estimate how much energy will be saved, says Beller. The process is still at an early stage, years away from commercialization.
But he thinks that it could be enough to make methanol a viable energy carrier
potentially delivering hydrogen for fuel cells in mobile phones, computers or even cars. Edman Tsang, a chemist at the University of Oxford, UK, who also works on storing hydrogen in liquids including methanol2,
says that the work is a major discovery. In particular, he says, the low temperature of the reaction is attractive
because it is about the same temperature as the waste heat from an operating hydrogen fuel cell.
That means that it may be possible to combine a methanol-hydrogen reaction with a fuel cell that guzzles up the gas to produce electricity.
To produce enough power to run a car, for example, the reaction would have to yield some 24 litres of hydrogen a second;
keeping carbon emissions from the process low. Despite the drawbacks, says Tsang, the conversion from methanol to hydrogen is worth pursuing:
hydrogen fuel cells are twice as efficient as fuel cells that directly run on methanol, for instance. Not everyone agrees with Beller and Tsang.
George Olah, a Nobel prizewinning chemist at the University of Southern California in Los angeles, thinks the science is solid,
Olah argues that a future economy could use methanol directly as a liquid fuel, so the world should work on ways to produce it#perhaps by capturing carbon dioxide.
Peter Hall, who studies energy storage at the University of Sheffield, UK, says that people who hope to use methanol,
or methanol-hydrogen systems, in cars or mobile phones are"seriously underestimating the engineering complexity of first developing a practical system
batteries will be key to energy transport and to small-scale storage of electricity from solar panels. Long-term, large-scale storage of wind energy could best be achieved by simply storing compressed hydrogen underground.
says Hall, is in communities that are isolated from the electricity grid but rely on harvesting renewable energy and storing it as hydrogen,
and want to move the gas around.""Methanol would be ideal for this application, since it could be transported easily by road,
#Circular RNAS throw genetics for a loop Behold the latest curio in the cabinet of RNA oddities:
naturally occurring circular RNA molecules that influence gene expression. At least some of the loops, described in two papers published this week by Nature1,
parallel universe of unexplored RNAS, says Nikolaus Rajewsky, the lead author of one of the studies and a systems biologist at the Max Delbr#ck Center for Molecular Medicine in Berlin.
or experimental artefacts, says Erik Sontheimer, a molecular biologist at Northwestern University in Evanston, Illinois. Instead,
But advances in sequencing have allowed biologists to accumulate large data sets of RNA sequences including some from RNA without tails.
Last year, Julia Salzman, a molecular biologist at Stanford university School of medicine in California, and her colleagues sent the first missive from the circular universe.
And when Rajewsky and his colleagues mined databases for circular RNA molecules, they found thousands in nematode worms, mice and humans."
and a second, independent team2 led by Thomas Hansen and J#rgen Kjems of Aarhus University in Denmark, focused on a circular behemoth, some 1, 500 nucleotides around,
They found that it contains about 70 binding sites for a microrna called mir-7. Micrornas are short fragments of RNA that can block gene expression by binding to
Mir-7 targets have been linked to cancer and Parkinson s disease. Hansen s team found that expression of the circular RNA blocked the blockers.
Some have possible binding sites for viral micrornas, which can subvert immune responses. Rajewsky hypothesizes that circular RNA could even interact with RNA BINDING-PROTEINS proteins.
"I can t think of another form we might have missed, laughs Phillip Sharp, a molecular biologist at the Massachusetts institute of technology in Cambridge."
Later, he learned that other patients were being treated aggressively by doctors chasing stringent LDL targets.
called ATP IV, has been drawn up by an expert panel of 15#cardiologists appointed by the institute.
US guidelines set by the Adult Treatment Panel (ATP) have lowered gradually acceptable levels for LDL bad cholesterol,
while shifting focus to prevention in patients at risk of a heart attack.""We can t just assume that modifying the risk factor is modifying risk,
says Harlan Krumholz, a cardiologist at Yale university in New haven, Connecticut.""We ve been burned so many times in the past decade by that assumption.
when ATP III called on doctors to push LDL levels below set targets, the concept of low cholesterol has become synonymous with heart health.
and some hospitals reward doctors when patients hit cholesterol targets. In 2011, US doctors wrote nearly 250#million prescriptions for cholesterol-lowering drugs,
creating a US$18. 5-billion market, according to IMS Health, a health-care technology and information company based in Danbury,
says Joseph Drozda, a cardiologist and director of outcomes research at Mercy Health in Chesterfield, Missouri."
ATP III reflected a growing consensus among physicians that sharply lowering cholesterol would lessen the likelihood of heart attacks
and strokes, says Richard Cooper, an epidemiologist at the Loyola University of Chicago Stritch School of medicine in Illinois,
The committee drew heavily on clinical data, but also took extrapolations from basic research and post hoc analyses of clinical trials.
and to focus on data from randomized clinical trials, says committee chairman Neil Stone, a cardiologist at Northwestern University School of medicine in Chicago.
If so, Krumholz argues, LDL targets will be cast aside because they have never been tested explicitly. Clinical trials have shown repeatedly that statins reduce the risk of heart attack and stroke,
but lowering LDL with other medications does not work as well. The benefits of statins may reflect their other effects on the body
including fighting inflammation, another risk factor for heart disease. Krumholz s scepticism is rooted in experience. In 2008 and 2010, the Action to Control Cardiovascular Risk in Diabetes (ACCORD) clinical trial challenged dogma
when it reported that lowering blood pressure or blood sugar to prespecified targets did not reduce the risk of heart attack or stroke.
In the case of blood sugar, the risks were worsened. The trial demonstrated the folly of assuming that risk factors must have a causal role in disease,
says Robert Vogel, a cardiologist at the University of Colorado, Denver.""Short people have a higher risk of heart disease,
he says.""But wearing high heels does not lower your risk. Jay Cohn, a cardiologist at the University of Minnesota Medical school in Minneapolis, also worries that the focus on LDL levels offers up the wrong patients for statin therapy.
Most of those who have a heart attack do not have high LDL, he notes. Cohn advocates treating patients with statins based on the state of health of their arteries,
as revealed by noninvasive tests such as ultrasound.""If your arteries and heart are healthy, I don t care
what your LDL or blood pressure is, he says.""We can t just assume that modifying the risk factor is modifying risk.
Not all cardiologists want to abolish LDL targets. Indeed, Seth Martin, a fellow in cardiology at Johns hopkins university School of medicine in Baltimore, Maryland, believes that ATP IV should reduce LDL targets further.
The simplicity of targets has helped to deliver an important public-health message, he says, and motivated many patients to get the statin therapy that he believes they need."
"Just to throw that out the window doesn t seem like the ideal scenario. Whatever the decision, the pharmaceutical industry will be watching closely,
says Donny Wong, an analyst at Decision Resources, a market-research company based in Burlington, Massachusetts.
Although most statins are off patent, the big pharmaceutical companies are racing to bring the next LDL-lowering drug to market.
In particular, millions of dollars have been poured into drugs that inhibit a protein called PCSK9, an enzyme involved in cholesterol synthesis. This approach lowers LDL
but has not yet been shown to reduce heart attacks or strokes. Francis expects the new guidelines to relax the targets.
He and his colleagues decided last autumn to change the VA s own clinical standards
but instead encourage doctors to prescribe a moderate dose of statin when otherwise healthy patients have high LDL cholesterol.
noting that the VA consulted several outside experts who are also serving on the ATP committee.
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