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Comment by Dr. Krishna Kumari Challa on January 31, 2014 at 8:37am

Observation of Dirac monopoles in a synthetic magnetic field
http://www.nature.com/nature/journal/v505/n7485/full/nature12954.html

Comment by Dr. Krishna Kumari Challa on January 31, 2014 at 8:29am

Acid bath offers easy path to stem cells

Just squeezing or bathing cells in acidic conditions can readily reprogram them into an embryonic state.
In 2006, Japanese researchers reported a technique for creating cells that have the embryonic ability to turn into almost any cell type in the mammalian body — the now-famous induced pluripotent stem (iPS) cells. In papers published this week in Nature, another Japanese team says that it has come up with a surprisingly simple method — exposure to stress, including a low pH — that can make cells that are even more malleable than iPS cells, and do it faster and more efficiently.
Yoshiki Sasai, a stem-cell researcher at the RIKEN Center for Developmental Biology in Kobe, Japan, and a co-author of the latest studies. It took Haruko Obokata, a young stem-cell biologist at the same centre, five years to develop the method and persuade Sasai and others that it works.

Obokata says that the idea that stressing cells might make them pluripotent came to her when she was culturing cells and noticed that some, after being squeezed through a capillary tube, would shrink to a size similar to that of stem cells. She decided to try applying different kinds of stress, including heat, starvation and a high-calcium environment. Three stressors — a bacterial toxin that perforates the cell membrane, exposure to low pH and physical squeezing — were each able to coax the cells to show markers of pluripotency.

But to earn the name pluripotent, the cells had to show that they could turn into all cell types — demonstrated by injecting fluorescently tagged cells into a mouse embryo. If the introduced cells are pluripotent, the glowing cells show up in every tissue of the resultant mouse. This test proved tricky and required a change in strategy. Hundreds of mice made with help from mouse-cloning pioneer Teruhiko Wakayama at the University of Yamanashi, Japan, were only faintly fluorescent. Wakayama, who had initially thought that the project would probably be a “huge effort in vain”, suggested stressing fully differentiated cells from newborn mice instead of those from adult mice. This worked to produce a fully green mouse embryo.

Still, the whole idea was radical, and Obokata’s hope that glowing mice would be enough to win acceptance was optimistic. Her manuscript was rejected multiple times, she says.

To convince sceptics, Obokata had to prove that the pluripotent cells were converted mature cells and not pre-existing pluripotent cells. So she made pluripotent cells by stressing T cells, a type of white blood cell whose maturity is clear from a rearrangement that its genes undergo during development. She also caught the conversion of T cells to pluripotent cells on video. Obokata called the phenomenon stimulus-triggered acquisition of pluripotency (STAP).

Her results suggested a different explanation: that pluripotent cells are created when the body’s cells endure physical stress. “The generation of these cells is essentially Mother Nature’s way of responding to injury,” says Vacanti, a co-author of the latest papers.

http://www.nature.com/news/acid-bath-offers-easy-path-to-stem-cells...

Comment by Dr. Krishna Kumari Challa on January 30, 2014 at 9:58am

Researchers Digitize Neuroscience’s Most Famous Brain

http://www.redorbit.com/news/science/1113057641/amnesiac-brain-digi...

Comment by Dr. Krishna Kumari Challa on January 30, 2014 at 7:15am

For more information please click on the links:
http://www.scientificamerican.com/article/psychopaths-might-have-an...
http://www.scientificamerican.com/article/inside-the-mind-of-a-psyc...

Comment by Dr. Krishna Kumari Challa on January 29, 2014 at 6:29am

Bio robots make a splash in the Indian Ocean
(CSIRO)
Robotic floats armed with revolutionary new sensors will be launched in the Indian Ocean, as part of a new India-Australia research partnership to find out what makes the world's third largest ocean tick - and how both nations can benefit from it.

The Indian Ocean contains vast fisheries and mineral resources that are of strategic importance to both Australia and India. It also plays a direct role in driving the climates of its surrounding regions - home to more than 16 per cent of the world's population.

The new 'Bio Argo' floats, to be launched in mid 2014, will enhance the already successful Argo float technology to measure large-scale changes in the chemistry and biology of marine ecosystems below the Indian Ocean's surface.

The Argo floats are a network of 3600 free-floating sensors, operating in open ocean areas that provide real-time data on ocean temperature and salinity.

The 'Bio Argo' floats will include additional sensors for dissolved oxygen, nitrate, chlorophyll, dissolved organic matter, and particle scattering. They will target specific gaps in our understanding of Indian Ocean ecosystems of immediate concern to India and Australia, such as the Bay of Bengal and the waters of north Western Australia.

CSIRO's Dr Nick Hardman-Mountford said the pilot project, led by CSIRO in collaboration with the Indian National Institute of Oceanography (CSIR-NIO) and the Indian National Centre for Ocean Information Services, will improve our understanding of cause and effect in the Indian Ocean's climate and ecosystems.

"By studying the Indian Ocean in this detail, we can investigate the origin and impact of marine heatwaves like the one that devastated the coral reefs and fisheries off north Western Australian in 2011 - and improve our prediction of them in the future," Dr Hardman-Mountford said.

CSIR-NIO Director, Dr Wajih Naqvi, said the novel technological innovation will give researchers from both countries a new understanding of the Indian Ocean.

"We expect the technology being utilised in this project to provide new insights into the biogeochemistry of the Indian Ocean and how it is being impacted by human activities," Dr Naqvi said.

The proposed advances in ocean observation, ecosystem understanding and resources management, which will benefit the entire Indian Ocean Rim, can only occur through collaboration between India and Australia.

Dr Nick D'Adamo, Head of the Perth Programme Office supporting UNESCO's Intergovernmental Oceanographic Commission (IOC) - a partner in the project - praised the collaborative nature of the project.

"By combining the research capabilities of India and Australia we will see an improved ability to predict and prepare for global climate change, as well as better conservation of marine biodiversity," Dr D'Adamo said.

The $1 million project was funded in part by the Australian Government under the Australia-India Strategic Research Fund.

Comment by Dr. Krishna Kumari Challa on January 28, 2014 at 9:39am

How Does The Brain Create Sequences?
And how do separate small elements come together to become a unique and meaningful sequence?

When you learn how to play the piano, first you have to learn notes, scales and chords and only then will you be able to play a piece of music. The same principle applies to speech and to reading, where instead of scales you have to learn the alphabet and the rules of grammar.

But how do separate small elements come together to become a unique and meaningful sequence?

It has been shown that a specific area of the brain, the basal ganglia, is implicated in a mechanism called chunking, which allows the brain to efficiently organize memories and actions. Until now little was known about how this mechanism is implemented in the brain.

In an article published today (Jan 26th) in Nature Neuroscience, neuroscientist Rui Costa, and his postdoctoral fellow, Fatuel Tecuapetla, both working at the Champalimaud Neuroscience Programme (CNP) in Lisbon, Portugal, and Xin Jin, an investigator at the Salk Institute, in San Diego, USA, reveal that neurons in the basal ganglia can signal the concatenation of individual elements into a behavioral sequence.

http://www.redorbit.com/news/science/1113055507/how-does-the-brain-...

Comment by Dr. Krishna Kumari Challa on January 28, 2014 at 9:09am

Truth about ordinary bulbs, CFLs and LEDs:

CFLs are 75 percent more efficient and LEDs 85 percent more efficient than a traditional incandescent light bulb. Lighting in residential homes is about 12 to 15 percent of an average home electrical bill, so the electricity savings to consumers are not trivial.
Moreover, power-saving bulbs last longer, so you will not have to make as many trips to the store. According to University of Kentucky lighting design professor and American Lighting Association consultant Joe Rey-Barreau, standard incandescent bulbs last an average of 1,000 hours, whereas CFLs last 10,000 hours and LEDs an astonishing 25,000 to 100,000 hours.
CFLs have some drawbacks. According to U.S. EPA, each CFL bulb contains about 4 milligrams of mercury. The concern is that, once broken, the bulb will emit potentially hazardous mercury vapor into the surrounding environment.

A 2011 study published in the journal Environmental Engineering Science by Jackson State University researchers Yadong Li and Li Jin revealed that mercury contents in CFLs vary significantly by brand and wattage, from 0.17 milligram to 3.6 milligrams.

The study found that the "vast majority of CFLs are nonhazardous" and that it would take weeks or even months for the mercury vapor released in a room to exceed the safe human exposure limit.
The LED is currently the most promising light source being sold on the consumer market. "The lack of mercury, the efficiency, the good color, the fact that it produces very little heat -- those are all benefits of the LED,"

http://www.scientificamerican.com/article/goodbye-and-good-riddance...

Comment by Dr. Krishna Kumari Challa on January 28, 2014 at 9:03am

Video: Debating the State of Global Science

Live from the 2014 World Economic Forum annual meeting in Davos, Switzerland

http://www.scientificamerican.com/article/video-debating-the-state-...

Comment by Dr. Krishna Kumari Challa on January 27, 2014 at 8:45am

Stephen Hawking, famous theoretical physicist and bestselling author, has created a flutter in the scientific world by proposing that what science has theorized about black holes may be wrong.

In a paper which is yet to be peer reviewed, Hawking suggests that black holes may not have an event horizon, the boundary that prevents any light or matter from escaping the clutches of its monstrous gravity, the scientific journal Nature reported today. What may exist is an "apparent horizon" which is much less tyrannical and only temporarily prevents matter and energy from escaping.

Hawking is considered as one of the world's foremost cosmologists and it was he who did most of the spadework for the theory of black holes in the 1970s. Later he proposed that 'event horizons' are not as impermeable as theorized and some matter or energy does manage to escape from them. This was dubbed Hawking Radiation.

According to Einstein's theory, a black hole is an entity in which matter has collapsed to a single point creating gigantic gravitational force, and trapping all energy or matter from ever escaping its clutches. Since light or any radiation cannot escape from a black hole, humans or their instruments can never directly 'see' a black hole although its existence is inferred from other symptoms nearby like high energy radiation emitted by matter just before falling into the black hole.

Quantum theory however allows energy to escape the black hole. This paradox - the variance between two theories that are true in their own conditions but fail in extreme conditions like the black hole - has troubled scientists for long. The only way out would be for some theory that could successfully merge gravity with the quantum mechanics.

Hawking's latest paper, titled "Information Preservation and Weather Forecasting for Black Holes" is available on the arXiv preprint server.

According to Nature, Hawking's paper is an "attempt to solve the so-called black-hole firewall paradox, which has been vexing physicists for almost two years". This paradox works like this: Einstein's theory predicts that if a space traveler were to fall into a black hole, he or she would just shoot through the event horizon with nary a ruffle and accelerate towards the black hole's infinitely dense core, all the time getting stretched longer and longer like a noodle. But quantum mechanics predicts that the event horizon should be a highly energetic region - a 'firewall' as Nature puts it - and the space traveler would be burnt to a cinder instantaneously.

Hawking's paper is the solution - a third way out of this paradox. He does away with the event horizon, saving both general relativity and quantum mechanics. Hawking's new idea is the 'apparent horizon' where energy like light rays speeding away from the black hole will be suspended. In some cases the event horizon may coincide with the apparent horizon, in others it may shrink below the apparent one.

This idea upturns the whole black hole mystique. "The absence of event horizons mean that there are no black holes — in the sense of regimes from which light can't escape to infinity," Hawking writes in the paper, according to Nature.

Comment by Dr. Krishna Kumari Challa on January 27, 2014 at 8:45am

Stephen Hawking now says there are no black holes - at least not in the way we perceive them !
Stephen Hawking has produced a "mind-bending" new theory that argues black holes do not actually exist — at least not in the way we currently perceive them. Instead, in his paper, Information Preservation and Weather Forecasting for Black Holes, Hawking proposes that black holes can exist without "event horizons" , the invisible cover believed to surround every black hole. During a previous lecture, "Into the Black Hole" , Hawkins described an event horizon as the boundary of a black hole, "where gravity is just strong enough to drag light back, and prevent it escaping" . "Falling through the event horizon, is a bit like going over Niagara Falls in a canoe" , he said. "If you are above the falls, you can get away if you paddle fast enough, but once you are over the edge, you are lost. There's no way back.

"As you get nearer the falls, the current gets faster. This means it pulls harder on the front of the canoe, than the back. There's a danger that the canoe will be pulled apart. It is the same with black holes."

But now, Hawking is proposing "apparent horizons" could exist instead, which would only hold light and information temporarily before releasing them back into space in "garbled form" , Nature has reported.

The internationally-renowned theoretical physicist suggests that quantum mechanics and general relativity remain intact, but black holes do not have an event horizon to catch fire.

His work attempts to address the "black-hole firewall paradox" first discovered by theoretical physicist Joseph Polchinski and his colleagues almost two years ago, when Polchinski and his team began investigating what would happen to an astronaut who fell into a black hole.

They hypothesised that instead of being gradually ripped apart by gravitational forces, the event horizon would be transformed into a "highly energetic region" , and anyone who fell in would hit a wall of fire and burn to death in an instant — violating Albert Einstein's theory of relativity.

In his paper, Hawking writes: "The absence of event horizons means that there are no black holes — in the sense of regimes from which light can't escape to infinity."

He told Nature jour nal: "There is no escape from a black hole in classical theory, but quantum theory, however, "enables energy and information to escape from a black hole."

Don Page, a physicist and expert on black holes at the University of Alberta in Edmonton, Canada told Nature that "the picture Hawking gives sounds pretty reasonable" .

"You could say that it is radical to propose there's no event horizon" , he said. "But these are highly quantum conditions, and there's ambiguity about what space-time even is, let alone whether there is a definite region that can be marked as an event horizon."

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