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Comment by Dr. Krishna Kumari Challa on May 2, 2014 at 9:10am

Excessive regulations turning scientists into bureaucrats
Scientists and institutions pinpointed regulations they believe are ineffective or inappropriately applied to research, and audit and compliance activities that take away research time and result in university over-regulation.
http://esciencenews.com/articles/2014/05/01/excessive.regulations.t...

Comment by Dr. Krishna Kumari Challa on May 2, 2014 at 8:39am

When E. coli cells aren't hanging out in a crowd, the rate at which their genes mutate to resist the antibiotic rifampicin increases up to threefold. The finding shows that the microbes' ability to develop antibiotic resistance depends on a gene that helps the bacterial cells communicate. Manipulating this type of crosstalk among bacterial cells may provide a way to slow the pervasive emergence of antibiotic resistance, researchers suggest April 29 in Nature Communications.

Comment by Dr. Krishna Kumari Challa on May 2, 2014 at 8:38am

A new study shows how the mammalian brain can distinguish the signal from the noise. Brain cells in the primary auditory cortex can both turn down the noise and increase the gain on the signal. The results show how the brain processes sound in noisy environments, and might eventually help in the development of better voice recognition devices, including improvements to cochlear implants for those with hearing loss. Not to mention getting Siri to understand you on a chaotic street corner.
''Mechanisms of noise robust representation of speech in primary auditory cortex''
the auditory system maintains a robust representation of speech in noisy and reverberant conditions by preserving the same statistical distribution of responses in all conditions. Reconstructed stimulus from population of cortical neurons resembles more the original clean than the distorted signal. We show that a linear spectrotemporal receptive field model of neurons with a static nonlinearity fails to account for the neural noise reduction. Although replacing static nonlinearity with a dynamic model of synaptic depression can account for the reduction of additive noise, only the combined model with feedback gain normalization is able to predict the effects across both additive and reverberant conditions.
Abstract

Humans and animals can reliably perceive behaviorally relevant sounds in noisy and reverberant environments, yet the neural mechanisms behind this phenomenon are largely unknown. To understand how neural circuits represent degraded auditory stimuli with additive and reverberant distortions, we compared single-neuron responses in ferret primary auditory cortex to speech and vocalizations in four conditions: clean, additive white and pink (1/f) noise, and reverberation. Despite substantial distortion, responses of neurons to the vocalization signal remained stable, maintaining the same statistical distribution in all conditions. Stimulus spectrograms reconstructed from population responses to the distorted stimuli resembled more the original clean than the distorted signals. To explore mechanisms contributing to this robustness, we simulated neural responses using several spectrotemporal receptive field models that incorporated either a static nonlinearity or subtractive synaptic depression and multiplicative gain normalization. The static model failed to suppress the distortions. A dynamic model incorporating feed-forward synaptic depression could account for the reduction of additive noise, but only the combined model with feedback gain normalization was able to predict the effects across both additive and reverberant conditions. Thus, both mechanisms can contribute to the abilities of humans and animals to extract relevant sounds in diverse noisy environments.
http://www.pnas.org/content/early/2014/04/17/1318017111

Comment by Dr. Krishna Kumari Challa on May 2, 2014 at 8:35am

Fiber's ability to curb appetite may come from gut molecules traveling to and acting on the brain, not the gut alone. As mice digest fiber, their guts release a molecule called acetate that appears to influence appetite suppression chemicals sent from the brain, researchers report April 29 in Nature Communications. The finding could open up new possibilities for weight management, the scientists say. It's unclear exactly how the gut-made acetate influences the brain chemicals that regulate appetite, and it's unknown wheather the amount of fiber given to the mice in the study would be part of a realistic diet.

Comment by Dr. Krishna Kumari Challa on May 2, 2014 at 8:23am

Comment by Dr. Krishna Kumari Challa on May 2, 2014 at 8:15am

Technique traces DNA direct to your ancestor's home 1,000 years ago
A new ground breaking technique has been developed which can locate the village your ancestors lived 1,000 years ago and hence trace back DNA formation.

Previously scientists had been able to link DNA formation to within a 700 km area which in a continent like Europe is very unreliable.

The Geographic Population Structure (GPS) tool created by Eran Elhaik from the University of Sheffield and Tatiana Tatarinova from the University of Southern California works similarly to a satellite navigation system.

The new technique has been 98% successful in locating worldwide populations to their right geographic regions down to their village and/ or island of origin.

The breakthrough has massive implications for life-saving personalized medicine, advancing forensic science and for the study of populations whose ancestral origins are under debate such as African Americans, Roma gypsies and European Jews.

Genetic admixture occurs when individuals from two or more previously separated populations interbreed. This results in the creation of a new gene pool representing a mixture of the founder gene pools.

Elhaik said, "What we have discovered here is a way to find not where you were born but where your DNA was formed up to 1,000 years ago by modelling these admixture processes. What is remarkable is that we can do this so accurately that we can locate the village where your ancestors lived hundreds and hundreds of years ago — until now this has never been possible."

Such processes were extremely common in history during migrations and invasions. When the Vikings invaded Britain and Europe in the 11th century and settled with locals some of them formed a new Viking-Anglo-Saxon gene pool but some married other Vikings and maintained their original gene pool allowing GPS to trace their Scandinavian origins.

Discovery of a certain genotype might indicate the potential for a genetic disease and suggest that diagnostic testing be done. Also as scientists learn more about personalized medicine there is evidence that specific genotypes respond differently to medications — making this information potentially useful when selecting the most effective therapy and appropriate dosage.

To demonstrate how accurate GPS predictions are, Elhaik analyzed data from 10 villages in Sardinia and over 20 islands in Oceania. The team was able to place a quarter of the residents in Sardinia directly to their home village and most of the remaining residents within 50km of their village.

The results for Oceania were no less impressive with almost 90% success of tracing islanders exactly to their island.

Tatarinova has now developed a website making GPS accessible to the public. "To help people find their roots, I developed a website that allows anyone who has had their DNA genotyped to upload their results and use GPS to find their ancestral home," Tatarinova said.

Comment by Dr. Krishna Kumari Challa on May 1, 2014 at 8:35am

Beware of False or Misleading Claims for Treating Autism
http://www.fda.gov/downloads/ForConsumers/ConsumerUpdates/UCM394800...
“There is no cure for autism,” the bulletin states. “So products or treatments claiming to ‘cure’ autism do not work as claimed. The same is true of many products claiming to ‘treat’ autism. Some may carry significant health risks.”

“Autism Speaks and its many partners are working diligently to find treatments for autism that are safe and effective,” comments developmental pediatrician Paul Wang, Autism Speaks senior vice president and head of medical research. “We know that parents often are desperate to find help for their children. It’s tragic when unscrupulous companies take advantage of these families by pushing so-called treatments that are not only ineffective, but may be costly and dangerous.”

Comment by Dr. Krishna Kumari Challa on May 1, 2014 at 8:33am

The Pen Is Mightier Than the Keyboard
Advantages of Longhand Over Laptop Note Taking
Students retain information better with pens than laptops
Writing notes by hand may lead to deeper understanding of lecture material, study suggests

Abstract

Taking notes on laptops rather than in longhand is increasingly common. Many researchers have suggested that laptop note taking is less effective than longhand note taking for learning. Prior studies have primarily focused on students’ capacity for multitasking and distraction when using laptops. The present research suggests that even when laptops are used solely to take notes, they may still be impairing learning because their use results in shallower processing. In three studies, we found that students who took notes on laptops performed worse on conceptual questions than students who took notes longhand. We show that whereas taking more notes can be beneficial, laptop note takers’ tendency to transcribe lectures verbatim rather than processing information and reframing it in their own words is detrimental to learning.
http://pss.sagepub.com/content/early/2014/04/22/0956797614524581

Comment by Dr. Krishna Kumari Challa on May 1, 2014 at 8:28am

Comment by Dr. Krishna Kumari Challa on May 1, 2014 at 8:09am

South Korean scientists have discovered how the colon hedges against cancerous cellular mutation.
South Korean scientist Cho Kwang-Hyun has identified the cancer inhibitory mechanism of the colon tissue, providing insights into the cause of colorectal cancer.
'' The APC Network Regulates the Removal of Mutated Cells from Colonic Crypts''
http://www.cell.com/cell-reports/abstract/S2211-1247%2814%2900157-0...

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