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Comment by Dr. Krishna Kumari Challa on December 3, 2014 at 6:07am

Dynamic mechanical behavior of multilayer graphene via supersonic projectile penetration
A new study results suggest graphene may absorb 10 times the amount of energy steel can before failing. The bullet was propelled into stacked graphene sheets at supersonic speeds of up to 2000mph by the gases produced by laser pulses rapidly evaporating a gold film. The team calculated the energy difference of the bullet before and after to determine the energy absorbed.
Graphene was able to absorb up to 0.92MJ/kg of ballistic energy in the test, with cracks forming around the impact zone. By comparison, steel targets only absorbed up to 0.08MJ/kg at the same speed.
The trick lies in energy absorption. If you can nucleate many cracks, it is a way of spreading the impact into more material. It is similar to that of tempered safety glass, a material engineered to spread damage and not locate it to a point. Graphene’s high performance is down to its high stiffness and low density, both of which control the speed of sound in the material. The stiffer and lighter the material is, the faster sound, stress and energy can travel through it. If you are able to spread the energy at higher speeds across the target area, more of the material will support the load and reduce the damaging effect of the bullet. Graphene’s dynamic strength is significant as it may behave similarly to materials specifically engineered to stop bullets, such as Kevlar, a fabric composed of aromatic polyamide threads.
http://www.sciencemag.org/content/346/6213/1092

Comment by Dr. Krishna Kumari Challa on December 3, 2014 at 5:52am

Brain Training Doesn’t Make You Smarter
Scientists doubt claims from brain training companies

http://www.scientificamerican.com/article/brain-training-doesn-t-ma...

Comment by Dr. Krishna Kumari Challa on December 2, 2014 at 7:52am

Researchers observe evolution of life forms that bear hallmarks of multicellular organisms
n ground-breaking study a team of researchers has reported the real time evolution of life forms that have all the hallmarks of multicellular organisms.

The researchers from New Zealand, Germany and the USA at the Max Planck Institute for Evolutionary Biology have observed in real time the evolution of simple self-reproducing groups of cells from previously individual cells.

The nascent organisms are comprised of a single tissue dedicated to acquiring oxygen, but this tissue also generates cells that are the seeds of future generations: a reproductive division of labour.

Intriguingly, the cells that serve as a germ line were derived from cheating cells whose destructive effects were tamed by integration into a life cycle that allowed groups to reproduce.

The life cycle turned out to be a spectacular gift to evolution and rather than working directly on cells, evolution was able to work on a developmental programme that eventually merged cells into a single organism.

When this happened groups began to prosper with the once free-living cells coming to work for the good of the whole.

When single bacterial cells of Pseudomonas fluorescens are grown in unshaken test tubes the cellular collectives prosper because they form mats at the surface of liquids where the cells gain access to oxygen that is otherwise in the liquid unavailable.

Lead author Paul Rainey explained that simple cooperating groups, like the mats that interest people, stand as one possible origin of multicellular life, but no sooner do the mats arise, than they fail, which is the same process that ensures their success, natural selection, ensures their demise.

-journal Nature,

Comment by Dr. Krishna Kumari Challa on December 2, 2014 at 7:01am

On the epoch of the Antikythera mechanism and its eclipse predictor
Scientists Have Made a Remarkable Discovery About the World's Oldest "Computer"
According to new research, the ancient Greek Antikythera Mechanism — sometimes called the world's "oldest analog computer" for its ability to predict lunar and solar eclipses and solar, lunar and planetary positions — may be much older than previously thought.

Based on recent analysis of the dials used to predict eclipses, Christián C. Carman, a science historian at the National University of Quilmes in Argentina, and James Evans, a physicist at the University of Puget Sound in Washington, have published new findings suggesting that the machine's dials actually start counting around 205 B.C., which would mean the device is 50 to 100 years older than researchers previously believed.

http://link.springer.com/article/10.1007/s00407-014-0145-5

Comment by Dr. Krishna Kumari Challa on November 30, 2014 at 8:35am

Comment by Dr. Krishna Kumari Challa on November 29, 2014 at 8:56am

Next battle in the war on science

The GOP Congress is ready to attack science agency funding in 2015.
GOP House members have had little success reining in research agencies so far, but, emboldened by their growing majorities, they’re hoping for better luck next year. They plan to push proposals to cut funding for global warming and social science research, put strict new rules on the National Science Foundation’s grant-making process and overhaul how science informs policy making at the EPA.

At the same time, however, researchers and their advocates in the Democratic caucus are taking increasingly aggressive stances of their own: Rather than answer GOP objections one by one, or brush them off, they’re making a larger issue of what they see as heavy-handed interference based on ideology rather than methodology.
Opponents in the scientific world and their political allies believe that, at its heart, the GOP assault isn’t about bringing greater accountability to the EPA or NSF, but rather a larger lack of trust in science that could soon spur efforts to micromanage NIH, the Department of Defense and other agencies that, all told, spend tens of billions on scientific research every year.

Researchers warn that funding only science that appears politically safe will stifle innovation and say that the agency actually does an impressive job of choosing which projects to fund.
But some in the research community say damage is already being done. Researchers will be less likely to apply for grants to fund unorthodox-sounding now — but potentially groundbreaking — research projects in future years, leaders of the Association of American Universities said recently in a statement.
Scientists and engineers, particularly young ones, should not be discouraged from pursuing unconventional, often groundbreaking scientific research.
More details here:
http://www.politico.com/story/2014/11/the-next-battle-in-the-war-on...

Comment by Dr. Krishna Kumari Challa on November 29, 2014 at 8:00am

Can DNA survive space travel?

It can , under certain circumstances , shows a new study

Genetic blueprints attached to a rocket survived a short spaceflight and later passed on their biological instructions!

A team of Swiss and German scientists report that they dotted the exterior grooves of a rocket with fragments of DNA to test the genetic material’s stability in space. Surprisingly, they discovered that some of those building blocks of life remained intact during the hostile conditions of the flight and could pass on genetic information even after exiting and reentering the atmosphere during a roughly 13-minute round trip into space.

So, if a cascade of meteors struck Earth billions of years ago, could they have deposited genetic blueprints and forged an indelible link between Earth and another planet?
 
Perhaps. Although that puzzling question remains unanswered, scientists have uncovered a new clue that suggests it is possible for DNA to withstand the extreme heat and pressure it would encounter when entering our atmosphere from space. The findings suggest that if DNA traveled through space on meteorites, it could have conceivably survived, says lead author Oliver Ullrich of the University of Zurich. Moreover, he says, “DNA attached to a spacecraft has the potential to contaminate other celestial bodies, making it difficult to determine whether a life form existed on another planet or was introduced there by spacecraft.” The rocket test may fall short of representing the faster speed and higher energy of a meteor hurtling into our atmosphere, but it does suggest that even if the outside of a meteor was scorched, genetic material in certain places on the meteor could survive higher temperatures than scientists had previously realized and make it to Earth. The researchers were intrigued to find that the DNA looked intact under a microscope in these experiments. They also put some of the samples to work to see if the DNA remained functionally capable of passing on genetic instructions. The team exposed Escherichia coli bacteria to the space-traveling DNA. If the plasmid DNA were intact — as it proved to be — the E. coli would be able to take up the DNA, and that piece of genetic code would make the bacteria resistant to antibiotics. According to Ullrich, the researchers were surprised to find that the DNA passed on its information and the E. coli became drug resistant. The findings are very exciting.

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone....

Comment by Dr. Krishna Kumari Challa on November 29, 2014 at 7:22am

Can sand dunes swallow people?

Yes, they can!

The Mystery of Why This Dangerous Sand Dune Swallowed a Boy

When a boy suddenly disappeared into a sand dune, a scientist embarked on a quest to find out where he went

But dunes aren’t supposed to contain holes  according to science. But this  appears to be a new geological phenomenon!

It might have been covered with quick sand. It was found  that the entire dune had shifted 134 metres away from the lakefront between 1938 and 2007, swallowing up long-forgotten trees, trails and stairs along the way. Four years later, it was revealed that the dune was flattening out, and the sand that facilitated its movement was coming from inside its inland slope - the area that was open to the public. The slope that swallowed the six year old boy. The age of the materials and the wet conditions during the spring of 2013 may have forced these materials to become unstable, collapsing and creating openings to the surface.

Through brute machine force (because it is difficult to dig sand), Nathan, the boy was uncovered in an unconscious state after 3.5 hours of excavation. Somehow, he'd end up surviving the ordeal, and two weeks later, walked out of the hospital. The doctors suspect either an air pocket in the sand hole saved him, or perhaps his body had reacted to the lack of oxygen by drastically slowing down the operation of his vital organs.


 http://www.smithsonianmag.com/science-nature/mystery-why-dangerous-...

Comment by Dr. Krishna Kumari Challa on November 28, 2014 at 8:32am

Tuesday, 25th November 2014

UNESCO Launches Online Science Education Resource

From UNESCO:

UNESCO launched the UNESCO World Library of Science (WLoS), a newly created, free online science education resource for a global community of users. Developed through the joint efforts of UNESCO, Nature Education and Roche, the WLoS was created to give students around the world, especially those in disadvantaged regions, access to the latest science information as well as the opportunity to share their experiences and learning through discussion with their peers in a shared learning environment.

Launched on the occasion of World Science Day for Peace and Development 2014, the WLoS is a science resource library stocked with over 300 top-quality articles, 25 eBooks, and over 70 videos from the publishers of Nature, the most cited scientific journal in the world. It is also a state-of-the-art digital platform that provides a community hub for learning. Users can join classes, build groups and connect with other learners.

http://www.unesco.org/new/en/natural-sciences/about-us/single-view/...

Comment by Dr. Krishna Kumari Challa on November 28, 2014 at 8:28am

Natural shield 11,000 km above Earth stops radiation
Researchers from Massachusetts Institute of Technology ( MIT) and University of Colorado in Boulder have discovered an invisible shield some 11,000 kms above Earth that works against the harmful radiation belt.
High above Earth's atmosphere, electrons whiz past at close to the speed of light.

Such ultra-relativistic electrons, which make up the outer band of the Van Allen radiation belt, can streak around the planet in a mere five minutes - bombarding anything in their path.
The Van Allen belts are a collection of charged particles - gathered in place by Earth's magnetic field.

Exposure to such high-energy radiation can wreak havoc on satellite electronics and pose serious health risks to astronauts. Rresearchers found no matter where these electrons are circling around the planet's equator, they can get no further than about 11,000 km from the Earth's surface - despite their intense energy. What is keeping this high-energy radiation at bay seems to be neither the Earth's magnetic field nor long-range radio waves but rather a phenomenon termed 'plasmaspheric hiss'.
The phenomenon is described as very low-frequency electromagnetic waves in the Earth's upper atmosphere that, when played through a speaker, resemble static or white noise.

The researchers believe that plasmaspheric hiss essentially deflects incoming electrons causing them to collide with neutral gas atoms in the Earth's upper atmosphere and ultimately disappear.
The paper on which this report is based was published in the journal Nature.

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