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Comment by Dr. Krishna Kumari Challa on January 31, 2014 at 9:53am

How to minimize radiation exposure during a nuclear attack using math:
https://www.sciencenews.org/blog/gory-details/nuclear-attack-there%...
Atmospheric scientist Michael Dillon of Lawrence Livermore National Laboratory in California has developed some helpful rules of thumb. He focused on minimizing total radiation exposure regardless of blast size, wind direction or many other factors that could affect radiation levels. In math terms, you’re minimizing the area under the curve of your radiation exposure over time: the integral, for those who took calculus.
One way to minimize that total exposure is to get to a location that blocks more radiation. The best shelter is belowground — say, in a basement. Hiding in the basement of a large apartment or office building can bring radiation levels down to one two-hundredth of the outdoor dose, a protection factor of 200. Being inside a one-story wooden house, on the other hand, may only cut your exposure in half, a protection factor of 2.
So what to do if you are caught in a poor shelter but think you can get to a better one? Here's where Dillon's math comes in. Essentially, you’re comparing the extra area added to your exposure curve while you’re outdoors with the area you’ll save by spending time in the better shelter later. Radiation levels will be tailing off over time; one rule of thumb is called the 7-10 rule: Seven hours after a blast, you’ll be getting one-tenth the dose received in the first hour.

The most important factors, Dillon found, are how long it has been since the detonation and how long it will take you to get to the better shelter. To minimize the area under your curve, you’re going to want to minimize the ratio of the time you spend in an initial poor-quality shelter to the time you spend outdoors getting to better shelter.
If you have access to only a poor-quality shelter initially (something like a wooden house with no basement) but can get to an adequate shelter (with a protection factor of 10 or more, like the basement of a wooden house) within five minutes, you should ditch the poor shelter immediately and go to the better shelter, Dillon reports January 14 in the Proceedings of the Royal Society A. If it will take you 15 minutes to get to the adequate shelter, you can still reduce your total exposure as long as you make your move within 30 minutes of the detonation. After that, your savings decline along with the outdoor radiation levels.
If you are in or able to immediately enter adequate shelter right after a blast, guidelines say you shoud stay put. You should probably stay in an interior room near the center of the building unless you're confident you can get to that supersafe basement before highly radioactive fallout starts raining down. "if you are outside of the building-collapse area immediately surrounding the detonation, you should have several minutes before fallout arrives." After that, it's unlikely you're going to have enough information to calculate whether your total dosage would be reduced by moving from adequate to better shelter, even if you've memorized the equations.

Once you’re hunkered down, you can generally expect to stay put for at least a couple hours in a minimally adequate shelter before trying to evacuate the area, and 24 hours or more if you're in a good shelter with a protection factor over 100 (again, minimizing your total exposure as outdoor levels fall). That decision can involve a different set of equations, based on wind speed and direction plus a whole host of other variables.

Comment by Dr. Krishna Kumari Challa on January 31, 2014 at 8:39am

Psychotic traits in comedians

Psychologists gave more than 500 funnymen a personality test that assesses traits associated with schizophrenia and bipolar disorder. And they found that the comics score higher than uncreative types, and even higher than actors, on a range of psychotic traits, including fear of intimacy, impulsive behavior, difficulty focusing and a belief in the paranormal.
Results: Comedians scored significantly above O-LIFE norms on all four scales. Actors also differed from the norms but on only three of the scales. Most striking was the comedians' high score on both introverted anhedonia and extraverted impulsiveness.

Conclusions: This unusual personality structure may help to explain the facility for comedic performance.
http://bjp.rcpsych.org/content/early/2014/01/02/bjp.bp.113.134569.a...

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-...

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