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Comment by Dr. Krishna Kumari Challa on May 3, 2014 at 5:37am

“The Improbability Principle” – The Book
Why is it that incredibly unlikely phenomena actually happen quite regularly and why should we, in fact, expect such things to happen? Here, in this highly original book – aimed squarely at anyone with an interest in coincidences, probability or gambling – eminent statistician David Hand answers this question by weaving together various strands of probability into a unified explanation, which he calls the improbability principle.

This is a book that will appeal not only to those who love stories about startling coincidences and extraordinarily rare events, but also to those who are interested in how a single bold idea links areas as diverse as gambling, the weather, airline disasters and creative writing as well as the origin of life and even the universe.

http://improbability-principle.com/the-improbability-principle-the-...

Comment by Dr. Krishna Kumari Challa on May 3, 2014 at 5:31am

Watch the Earth From Space, Live!
http://blogs.scientificamerican.com/life-unbounded/2014/05/01/watch...

Comment by Dr. Krishna Kumari Challa on May 2, 2014 at 9:17am

Decoding the chemical vocabulary of plants
Plants spend their entire lifetime rooted to one spot. When faced with a bad situation, such as a swarm of hungry herbivores or a viral outbreak, they have no option to flee but instead must fight to survive. What is the key to their defense? Chemistry. Thanks to this ongoing conflict, plants have evolved into amazing chemists, capable of synthesizing tens of thousands of compounds from thousands of genes. These chemicals, known as specialized metabolites, allow plants to withstand transient threats from their environment. What's more, some of the same compounds benefit humans, with more than a third of medicinal drugs derived from plant specialized metabolites.

Understanding how plants evolved this prodigious chemical vocabulary has been a longstanding goal in plant biology. A team of Carnegie scientists led by Seung Yon Rhee and Lee Chae undertook a large-scale comparative analysis of plant genomes to investigate how specialized metabolism evolved. Their findings, as reported in Science, have major implications for the way scientists search for novel beneficial metabolites in plants.
Collectively, these properties represent a distinct signature of specialized metabolic genes that offers an innovative strategy for the discovery of novel specialized metabolites from various plant species. Such discoveries could have wide-ranging implications for many research fields, including agriculture, biotechnology, drug discovery, and synthetic biology.

"Despite our reliance on plant compounds for health and well-being, we know very little about how they are produced or the true extent of their diversity in nature," says Rhee. "We hope that our findings will enable researchers to use these signatures as a tool to discover previously unknown specialized metabolites, to investigate how they benefit the plant, and to determine how they might benefit us."
http://esciencenews.com/articles/2014/05/01/decoding.chemical.vocab...
Source: Carnegie Institution

Comment by Dr. Krishna Kumari Challa on May 2, 2014 at 9:12am

Antimicrobial agents incorporated into edible films applied to foods to seal in flavor, freshness and color can improve the microbiological safety of meats, according to researchers in Penn State's College of Agricultural Sciences. Using films made of pullulan -- an edible, mostly tasteless, transparent polymer produced by the fungus Aureobasidium pulluns -- researchers evaluated the effectiveness of films containing essential oils derived from rosemary, oregano and nanoparticles against foodborne pathogens associated with meat and poultry.

The results demonstrate that the bacterial pathogens were inhibited significantly by the use of the antimicrobial films, said Catherine Cutter, professor of food science. She hopes that the research will lead to the application of edible, antimicrobial films to meat and poultry, either before packaging or, more likely, as part of the packaging process.

In the study, which was published online in the April issue of the Journal of Food Science, researchers determined survivability of bacterial pathogens after treatment with 2 percent oregano essential oil, 2 percent rosemary essential oil, zinc oxide nanoparticles or silver nanoparticles.
http://esciencenews.com/articles/2014/05/01/antimicrobial.edible.fi...

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.

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