Washington, September 16 (ANI): A new research has cast doubts on the value of climate envelope models, saying more than 60 per cent of such studies maybe wrong.

According to a report in Nature News, estimates of the impact climate change will have on wildlife may be much less reliable than thought, with a research that is reopening debate over a widely used modelling method endorsed by the Intergovernmental Panel on Climate Change (IPCC).

'Climate envelope' models use current distributions of species to construct an idea of the climatic conditions that suit them. This 'envelope' can then be used to see where species could live under predictions of future climate.

Use of climate envelope models has been contentious, not least because they omit a number of factors that may be as or more important than climate in controlling species distribution, for example human activity, interactions with other species and pure chance.

Now, a paper from Colin Beale of the UK's Macaulay Institute of Land Use Research, in Aberdeen, and colleagues has cast further doubt on the value of climate envelope models, saying they quite frequently do no better than chance in explaining why species live where they do.

"At the moment, people are overconfident in our ability to make these projections," said Beale. "We really need to start to think about models that include a lot more biology," he added.

Beale and his colleagues began by generating climate envelopes based on real distribution data for 100 European bird species. Then, they created 99 artificial distribution patterns for each of the real patterns.

These 'null' distributions were designed to mimic the aspatial structure of the birds' real distribution, but were created with no reference to climate at all.

"This model is no better than a chance association: it is certainly not a model that should inform policy," said Beale.

The researchers then made climate envelope models for both the real and artificial distribution patterns for all 100 species.

Then, they applied a statistical 'goodness-of-fit' test to determine how well the distribution data, both real and artificial, fitted into the climate envelope models based on them, and ranked the distributions for each species according to this measure.

For 68 of the 100 species, the five distributions that fitted their climate envelopes best were null distributions.

So, climate envelopes generated from real distribution data did not describe that data as well as some of the climate envelopes fitted to distribution data made up without any thought of climate.

The team takes this to imply that the association between the climate envelope and the animals' range is in many cases no better than chance. (ANI)

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London, September 16 (ANI): New observations from the 40-inch Wise Observatory telescope in Israel has revealed more than a dozen galaxies lined up along a bridge of dark matter inside a region of nearly empty space, which is being called as 'bridge to nowhere' by astronomers.

According to a report in New Scientist, this 'bridge to nowhere' could shed light on how small galaxies formed in the early universe.

Galaxies in the universe are arranged in a lacy structure that contains many holes, or voids, that are largely bereft of galaxies.

But, the voids are not completely empty; astronomers expect they are criss-crossed by filaments of dark matter.

Now, astronomers have found a total of 14 galaxies that appear to be part of a dark matter bridge at least 1.5 million light years long.

The string of galaxies spans just 0.5 per cent of a 'mini-void' - a region of space containing mostly dim, dwarf galaxies kept small by their relative isolation from other matter.

But, the underlying dark matter bridge may be far longer than that.

All of the galaxies are small dwarfs that seem to be unrelated. But, Adi Zitrin and Noah Brosch of Tel Aviv University in Israel noticed that they all seemed to be arrayed in a line.

Further study revealed that after more than a billion years of inactivity, all of the galaxies began forming stars again less than 30 million years ago.

That was unexpected, since new star formation often occurs when galaxies interact, and these seem to be keeping to themselves. Nearby galaxies, for example, did not seem to have more star formation than those lying farther away.

"This is a strange thing," Brosch told New Scientist. "A priori, one would not expect galaxies that have nothing to do with each other, a few million light years apart, to make stars at the same time," he added.

That synchronization seems to suggest that the galaxies have come into contact with new, star-forming material, like a passing cloud of gas.

Ordinarily, the gas would be too tenuous to condense down and cause a new burst of star formation.

"But if a swath of dark matter is connecting the galaxies, its gravity could help concentrate the material," said Brosch.

If the galaxies are pinned to a filament of dark matter, further study could help illuminate how star formation occurred in the early universe, he added.

That's because the first galaxies are thought to have gotten their start when gas accumulated around denser regions of dark matter.

Solidifying the case for a filament might be possible by observing objects lying behind the void.

According to John Huchra of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, if their light is bent travelling through the void, the gravitational effect of unseen dark matter could be to blame. (ANI)

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Washington, September 16 (ANI): Experiments on mice conducted by Rutgers geneticists have unveiled a gene that promotes "helicopter mom" behaviour in the animal.

Research leader Gleb Shumyatsky, an assistant professor of genetics in the School of Arts and Sciences at Rutgers, says that the gene called stathmin, or oncoprotein 18, motivates female animals to protect newborn pups and interact cautiously with unknown peers.

The researcher has revealed that the "fear gene" is highly concentrated in the amygdala, a key region of the brain that deals with fear and anxiety.

The new discovery attains significance as it may help improve scientists understanding of human anxiety, including partpartum depression and borderline personality disorders.

For their study, the researchers genetically engineered female mice to have an inactive stathmin gene.

Shumyatsky observed that the mutant mice were slow to retrieve pups placed outside the nest at corners of the cage.

However, mice with normally active stathmin were quick to bring similarly dispersed pups back to the nest.

In another experiment, knockout mice chose to rebuild nests in more vulnerable open spaces instead of in safe corners, where normal mice typically build nests.

Shumyatsky attributed the abnormal behaviour to the mouse's lack of fear for the safety of pups in her care.

Shumyatsky and postdoctoral research collaborators Guillaume Martel and Akinori Nishi conducted several experiments to rule out other reasons why the mutant mice were slow to retrieve pups, and ruled out diminished olfactory perception.

The researchers observed that both normal and mutant mice located missing pups with equal speed using their sense of smell.

Both types of mice also equally passed object perception tests, and the researchers ruled out non-fear motivation, as both types stockpiled food with the expected urgency.

In the social behaviour experiment, the mutant mice showed much less cautious behavior to other peers than did the normal mice.

"The equivalent human behavior would be if a person hugged every stranger she met. In fact, that's something that humans with amygdalar damage might do - they're very trusting," said Shumyatsky.

The researchers say that their findings add further evidence to the amygdala's role in controlling innate fears.

A research article describing the study has been published in the online edition of the journal Proceedings of the National Academy of Sciences (PNAS). (ANI)

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Washington, September 16 (ANI): NASA is aiming to power its planned base at the Moon with a nuclear reactor that will be part of a technology development program known as the fission Surface Power Project.

According to a report in Discovery News, the goal of the Fission Surface Power Project, which is based at NASA's Glenn Research Center in Cleveland, Ohio, is to produce a non-nuclear prototype unit within five years.

Supported at a cost of about 10 million dollars a year, the project has already awarded two contracts for power conversion units, used to turn the heat of nuclear reactions into electricity.

NASA envisions needing a system capable of providing about 40 kilowatts of electricity - about what's used to power eight average homes in the United States.

It would be launched cold and without radioactive elements until operations were to begin on the lunar surface.

NASA is thinking about burying the system so the lunar soil can serve as shielding.

The converter design by Sunpower Inc., of Athens, Ohio, uses two opposed piston engines coupled to alternators to produce a total of 12 kilowatts of power.

Barber Nichols Inc. of Arvada, Colorado, is developing a closed Brayton cycle engine that uses a high-speed turbine and compressor coupled to a rotary alternator. It also generates 12 kilowatts.

According to project manager Lee Mason, "Our goal is to build a technology demonstration unit with all the major components of a fission surface power system and conduct non-nuclear, integrated system testing in a ground-based space simulation facility."

A space-based reactor would have to be much more compact than fission reactors currently operating on Earth and would generate far less power.

The agency also is looking at solar-powered technologies, fuel cells and other systems.

Among engineers' challenges are the harsh, radioactive environments and the extreme temperature ranges of space.

The moon's 29.5-day rotational period produces long, cold nights lasting 354 hours, which presents a formidable challenge for solar-powered systems.

On Mars, the night-time is just 12 hours, but its distance from sun means only 20 percent of the energy that reaches the moon makes it to Mars.

"As you get further and further out, the missions get longer and longer, and you're going to have to have higher and higher power levels," said John Warren, who oversees the program at NASA headquarters in Washington D.C.

"You're probably going to have to have nuclear, and I think that will be recognized not only here in the US, but around the world," he added. (ANI)

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