Science Simplified!

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Comment by Dr. Krishna Kumari Challa on April 2, 2014 at 9:21am

Understanding the different categories of facial expressions of emotion regularly used by us is essential to gain insights into human cognition and affect as well as for the design of computational models and perceptual interfaces. Past research on facial expressions of emotion has focused on the study of six basic categories—happiness, surprise, anger, sadness, fear, and disgust. However, many more facial expressions of emotion exist and are used regularly by humans. This paper describes an important group of expressions, which we call compound emotion categories. Compound emotions are those that can be constructed by combining basic component categories to create new ones. For instance, happily surprised and angrily surprised are two distinct compound emotion categories. The present work defines 21 distinct emotion categories. Sample images of their facial expressions were collected from 230 human subjects. A Facial Action Coding System analysis shows the production of these 21 categories is different but consistent with the subordinate categories they represent (e.g., a happily surprised expression combines muscle movements observed in happiness and surprised). We show that these differences are sufficient to distinguish between the 21 defined categories. We then use a computational model of face perception to demonstrate that most of these categories are also visually discriminable from one another.
Compound facial expressions of emotion
http://www.pnas.org/content/early/2014/03/25/1322355111

Comment by Dr. Krishna Kumari Challa on April 2, 2014 at 9:16am

Methane-spewing microbe blamed in Earth's worst mass extinction
A tiny methane-producing microbe may have been responsible for the largest mass extinction in Earth's history.

Fossil remains show sometime around 252 million years ago, about 90% of all species on Earth were suddenly wiped out — by far the largest of this planet's five known mass extinctions. But pinpointing the culprit has been difficult till now.

A team of MIT researchers has found enough evidence to reveal what caused it. They say we will need a microscope to see the killers.

The perpetrators, according to the new study, were not asteroids, volcanoes or raging coal fires — all of which have been implicated previously. Rather, they were a form of microbes — specifically, methane-producing archaea called Methanosarcina — that suddenly bloomed explosively in the oceans, spewing prodigious amounts of methane into the atmosphere and dramatically changing the climate and chemistry of the oceans.

The reason for the sudden, explosive growth of the microbes may have been their novel ability to use a rich source of organic carbon, aided by a sudden influx of a nutrient required for their growth: the element nickel, emitted by massive volcanism at just that time.

MIT professor of geophysics Daniel Rothman, postdoc Gregory Fournier and five other researchers at MIT and in China built upon three independent sets of evidence.

First, geochemical evidence shows an exponential increase of carbon dioxide in the oceans at the time of the so-called end-Permian extinction. Second, genetic evidence shows a change in Methanosarcina at that time, allowing it to become a major producer of methane from an accumulation of carbon dioxide in the water. Finally, sediments show a sudden increase in the amount of nickel deposited at exactly this time.

The carbon deposits show something caused a significant uptick in the amount of carbon-containing gases — carbon dioxide or methane — produced at the time of the mass extinction.

"A rapid initial injection of carbon dioxide from a volcano would be followed by a gradual decrease," Fournier says. "Instead, we see the opposite: a rapid, continuing increase. That suggests a microbial expansion. The growth of microbial populations is among the few phenomena capable of increasing carbon production exponentially or even faster."

Scientists then carried out genomic analysis of what caused this.

It turns out that Methanosarcina had acquired a particularly fast means of making methane, through gene transfer from another microbe — and the team's detailed mapping of the organism's history now shows this transfer happened at about the time of the end-Permian extinction.

The resulting outburst of methane produced effects similar to those predicted by current models of global climate change: a sudden, extreme rise in temperatures, combined with acidification of the oceans. In the case of the end-Permian extinction, virtually all shell-forming marine organisms were wiped out — consistent with the observation that such shells cannot form in acidic waters.
- Reuters

Comment by Dr. Krishna Kumari Challa on April 2, 2014 at 9:01am

Deforestation of sandy soils a greater climate threat
Deforestation may have far greater consequences for climate change in some soils than in others, according to new research led by Yale University scientists -- a finding that could provide critical insights into which ecosystems must be managed with extra care because they are vulnerable to biodiversity loss and which ecosystems are more resilient to widespread tree removal. In a comprehensive analysis of soil collected from 11 distinct U.S. regions, from Hawaii to northern Alaska, researchers found that the extent to which deforestation disturbs underground microbial communities that regulate the loss of carbon into the atmosphere depends almost exclusively on the texture of the soil. The results were published in the journal Global Change Biology.
http://environment.yale.edu/

Comment by Dr. Krishna Kumari Challa on April 1, 2014 at 8:46am

Debashis Chanda at the University of Central Floridamay have just cracked a barrier. The cover story in the March edition of the journal Advanced Optical Materials, explains how Chanda and fellow optical and nanotech experts were able to develop a larger swath of multilayer 3-D metamaterial operating in the visible spectral range. They accomplished this feat by using nanotransfer printing, which can potentially be engineered to modify surrounding refractive index needed for controlling propagation of light.
A breakthrough in creating invisibility cloaks, stealth technology
The nanotransfer printing technique creates metal/dielectric composite films, which are stacked together in a 3-D architecture with nanoscale patterns for operation in the visible spectral range. Control of electromagnetic resonances over the 3-D space by structural manipulation allows precise control over propagation of light. Following this technique, larger pieces of this special material can be created, which were previously limited to micron-scale size.

By improving the technique, the team hopes to be able to create larger pieces of the material with engineered optical properties, which would make it practical to produce for real-life device applications. For example, the team could develop large-area metamaterial absorbers, which would enable fighter jets to remain invisible from detection systems.
Source: University of Central Florida

Comment by Dr. Krishna Kumari Challa on April 1, 2014 at 8:37am

Nano-paper filter removes viruses
Researchers at the Division of Nanotechnology and Functional Materials, Uppsala University have developed a paper filter, which can remove virus particles with the efficiency matching that of the best industrial virus filters. The paper filter consists of 100 percent high purity cellulose nanofibers, directly derived from nature. The research was carried out in collaboration with virologists from the Swedish University of Agricultural Sciences/Swedish National Veterinary Institute and is published in the Advanced Healthcare Materials journal.

Virus particles are very peculiar objects- tiny (about thousand times thinner than a human hair) yet mighty. Viruses can only replicate in living cells but once the cells become infected the viruses can turn out to be extremely pathogenic. Viruses can actively cause diseases on their own or even transform healthy cells to malignant tumors.
http://esciencenews.com/articles/2014/03/31/nano.paper.filter.remov...

Comment by Dr. Krishna Kumari Challa on April 1, 2014 at 7:31am

Feel happy to read these type of articles
Airlines find a smart way to cut carbon footprint
http://timesofindia.indiatimes.com/business/india-business/Airlines...
This is to save money( economics) but at the same time they are helping the ecology!
Perhaps if you show people things that can be helpful both ways, they would listen!

Comment by Dr. Krishna Kumari Challa on March 31, 2014 at 8:43am

First gene-editing disease cure success announced
Using a new gene-editing system based on bacterial proteins, MIT researchers have cured mice of a rare liver disorder caused by a single genetic mutation.

The findings, described in the March 30 issue of Nature Biotechnology, offer the first evidence that this gene-editing technique, known as CRISPR, can reverse disease symptoms in living animals. CRISPR, which offers an easy way to snip out mutated DNA and replace it with the correct sequence, holds potential for treating many genetic disorders, according to the research team.

http://newsoffice.mit.edu/2014/erasing-genetic-mutation

Comment by Dr. Krishna Kumari Challa on March 31, 2014 at 8:41am

Scientists struggle to complete climate impacts report
http://www.bbc.com/news/science-environment-26802192

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

V-ATPase Proton Pumping Activity Is Required for Adult Zebrafish Appendage Regeneration
Reason why some animals can regenerate tissues after severe organ loss or amputation while others, such as humans, cannot renew some structures has always intrigued scientists. In a study now published in PLOS ONE, a research group from Instituto Gulbenkian de Ciência (IGC, Portugal) led by Joaquín Rodríguez León provided new clues to solve this central question by investigating regeneration in an adult vertebrate model: the zebrafish. It was known that zebrafish is able to regenerate organs, and that electrical currents may play a role in this process, but the exact mechanisms are still unclear. Using both biophysical and molecular approaches, the researchers have shown, for the first time, that zebrafish regenerates its caudal fin by a process that involves a specific channel in the cell membrane, called V-ATPase, that pumps hydrogen ions (H+) out of the cells generating an electrical current. Understanding these mechanisms underlying adult tissue regeneration may be instrumental for the development of new tissue.
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone....

Comment by Dr. Krishna Kumari Challa on March 29, 2014 at 6:15am

Geoengineering side effects could be potentially disastrous, research shows
Comparison of five proposed methods shows they are ineffective, alter weather systems or could not be safely stopped

http://www.nature.com/ncomms/2014/140225/ncomms4304/full/ncomms4304...
http://www.theguardian.com/environment/2014/feb/25/geoengineering-s...

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