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Comment by Dr. Krishna Kumari Challa on December 24, 2014 at 7:06am

Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness

Abstract

In the past 50 y, there has been a decline in average sleep duration and quality, with adverse consequences on general health. A representative survey of 1,508 American adults recently revealed that 90% of Americans used some type of electronics at least a few nights per week within 1 h before bedtime. Mounting evidence from countries around the world shows the negative impact of such technology use on sleep. This negative impact on sleep may be due to the short-wavelength–enriched light emitted by these electronic devices, given that artificial-light exposure has been shown experimentally to produce alerting effects, suppress melatonin, and phase-shift the biological clock. A few reports have shown that these devices suppress melatonin levels, but little is known about the effects on circadian phase or the following sleep episode, exposing a substantial gap in our knowledge of how this increasingly popular technology affects sleep. Here we compare the biological effects of reading an electronic book on a light-emitting device (LE-eBook) with reading a printed book in the hours before bedtime. Participants reading an LE-eBook took longer to fall asleep and had reduced evening sleepiness, reduced melatonin secretion, later timing of their circadian clock, and reduced next-morning alertness than when reading a printed book. These results demonstrate that evening exposure to an LE-eBook phase-delays the circadian clock, acutely suppresses melatonin, and has important implications for understanding the impact of such technologies on sleep, performance, health, and safety.
http://www.pnas.org/content/early/2014/12/18/1418490112

Comment by Dr. Krishna Kumari Challa on December 23, 2014 at 9:05am

Researchers at Montana State University and Brandenburg University of Applied Sciences in Germany have created a simple mathematical model based on optical measurements that explains the stunning colors of Yellowstone National Park's hot springs and can visually recreate how they appeared years ago, before decades of tourists contaminated the pools with make-a-wish coins and other detritus.
Using a relatively simple one-dimensional model for light propagation, the group was able to reproduce the brilliant colors and optical characteristics of Yellowstone National Park’s hot springs by accounting for each pool’s spectral reflection due to microbial mats, their optical absorption and scattering of water and the incident solar and diffuse skylight conditions present when measurements were taken.
While the basic physical phenomena that render these colorful delights have long been scientifically understood -- they arise because of a complicated interplay of underwater vents and lawns of bacteria -- no mathematical model existed that showed empirically how the physical and chemical variables of a pool relate to their optical factors and coalesce in the unique, stunning fashion that they do.
Using a relatively simple one-dimensional model for light propagation, the group was able to reproduce the brilliant colors and optical characteristics of Yellowstone National Park's hot springs by accounting for each pool's spectral reflection due to microbial mats, their optical absorption and scattering of water and the incident solar and diffuse skylight conditions present when measurements were taken. In the case of Morning Glory Pool, they were even able to simulate what the pool once looked like between the 1880s and 1940s, when its temperatures were significantly higher. During this time, its waters appeared a uniform deep blue. An accumulation of coins, trash and rocks over the intervening decades has partially obscured the underwater vent, lowering the pool's overall temperature and shifting its appearance to a terrace of orange-yellow-green. This change from blue was demonstrated to result from the change in composition of the microbial mats, as a result of the lower water temperature.
A general relationship between shallow water temperature (hence microbial mat composition) and observed colors was confirmed in this study. However, color patterns observed in deeper segments of the pool are caused more by absorption and scattering of light in the water. These characteristics - mats having greater effect on color in shallow water, and absorption and scattering winning out in the deeper areas - are consistent across all the measured pools.

Comment by Dr. Krishna Kumari Challa on December 23, 2014 at 8:56am

Plants are changing their 'eating choices'
A carnivorous plant that is turning vegetarian
The bladderworts (Utricularia) is a species of carnivorous plant that catches and digests tiny animals.

Now, the plant is turning to algae and pollen grains for a balanced nutrition.
The species catches its prey with the help of suction bladders, trap doors and lightning speed.

Once captured by the bladderwort, the animal suffocates, and is then broken down by enzymes and digested.

This is how the plant worked until it discovered vegetarianism.

"Bladderworts are switching to algae and pollen grains," said researchers Marianne Koller-Peroutka and Wolfram Adlassnig from the University of Vienna in Austria.

When bladderworts lived in areas where algae was plenty and animals were scarce, the vegetarian plants were actually larger than the meat eaters.

Consuming animals gave the plants a higher nitrogen content which increased the development of hibernation buds which are critical to helping them survive over cold winters.
The bladderworts (Utricularia) are one of the largest genera (a principal taxonomic category that ranks above species and below family) in carnivorous plants with over 200 species.

The study appeared in the journal Annals of Botany.

Comment by Dr. Krishna Kumari Challa on December 18, 2014 at 8:04am

Quantum-secure authentication of a physical unclonable key

Credit cards and ID cards which could never be hacked? That's the promise of quantum cryptography, which harnesses peculiar properties of subatomic particles to thwart data thieves.

Now a team of Dutch researchers says we're closer to making such technology a practical reality.

Publishing in the current issue of Optica, scientists at the University of Twente and Eindhoven University of Technology describe what they call quantum-secure authentication (QSA) of a "classical multiple-scattering key."
Authentication of persons and objects is a crucial aspect of security. We experimentally demonstrate quantum-secure authentication (QSA) of a classical multiple-scattering key. The key is authenticated by illuminating it with a light pulse containing fewer photons than spatial degrees of freedom and verifying the spatial shape of the reflected light. Quantum-physical principles forbid an attacker to fully characterize the incident light pulse. Therefore, he cannot emulate the key by digitally constructing the expected optical response, even if all information about the key is publicly known. QSA uses a key that cannot be copied due to technological limitations and is quantum-secure against digital emulation. Moreover, QSA does not depend on secrecy of stored data, does not depend on unproven mathematical assumptions, and is straightforward to implement with current technology.
http://www.opticsinfobase.org/optica/abstract.cfm?uri=optica-1-6-421

Comment by Dr. Krishna Kumari Challa on December 18, 2014 at 7:44am

Low glycemic index foods do not reduce risk factors for cardiovascular disease and diabetes
In a 5-week controlled feeding study, diets with low glycemic index of dietary carbohydrate, compared with high glycemic index of dietary carbohydrate, did not result in improvements in insulin sensitivity, lipid levels, or systolic blood pressure. In the context of an overall DASH-type diet, using glycemic index to select specific foods may not improve cardiovascular risk factors or insulin resistance.

http://jama.jamanetwork.com/article.aspx?articleid=2040224

Comment by Dr. Krishna Kumari Challa on December 18, 2014 at 7:31am

Antimicrobial resistance will kill 300 million by 2050 without action
http://www.rsc.org/chemistryworld/2014/12/antimicrobial-resistance-...

Comment by Dr. Krishna Kumari Challa on December 17, 2014 at 8:24am

Messages received from Voyager 1, the Nasa spacecraft travelling 19.5 billion kms away from Earth, show that it is continuing to experience a "tsunami wave" as it penetrates the interstellar medium beyond the solar System.

The spacecraft launched in 1977 is the farthest a man made object has gone from Earth ever. So far, signals from its instruments travelling at the speed of light take 36 hours and 14 minutes to reach Earth.

"Most people would have thought the interstellar medium would have been smooth and quiet. But these shock waves seem to be more common than we thought," said Don Gurnett, professor of physics at the University of Iowa in Iowa City. Gurnett presented the new data Monday, Dec. 15 at the American Geophysical Union meeting in San Francisco.

A "tsunami wave" occurs when the sun emits a coronal mass ejection, throwing out a magnetic cloud of plasma from its surface. This generates a wave of pressure. When the wave runs into the interstellar plasma -- the charged particles found in the space between the stars -- a shock wave results that perturbs the plasma.

"The tsunami causes the ionized gas that is out there to resonate -- "sing" or vibrate like a bell," said Ed Stone, project scientist for the Voyager mission based at California Institute of Technology in Pasadena.

Comment by Dr. Krishna Kumari Challa on December 17, 2014 at 8:07am

Celiac disease: Immune responses to wheat go beyond gluten

The immune response to gluten in wheat and related cereals in celiac disease is well established but whether other cereal components also induce an immune response is less well understood. A new paper published online in the Journal of Proteome Research suggests that non-gluten proteins in wheat do trigger an immune reaction and could potentially contribute to celiac disease.
http://pubs.acs.org/doi/abs/10.1021/pr500809b

Comment by Dr. Krishna Kumari Challa on December 17, 2014 at 7:28am

Humans First Built Fire 350000 Years Ago
New evidence from an Israeli cave indicates that humans first built fires around 350,000 years ago, according to a new study.

An international team led by Ron Shimelmitz from the University of Haifa examined flint debris and tools discovered in the Tabun Cave in northern Israel. While the study finds archaeological evidence of fire dating back to a million years ago, researchers focus on humans' habitual use of fire.
http://www.academia.edu/8858729/Fire_at_will_The_emergence_of_habit...

The use of fire is central to human survival and to the processes of becoming human. The earliest evi-dence for hominin use of fire dates to more than a million years ago. However, only when fire use became a regular part of human behavioral adaptations could its benefits be fully realized and its evolutionaryconsequences fully expressed. It remains an open question when the use of

fire shifted from occasional and opportunistic to habitual and planned. Understanding the time frame of this 'technological mutation' will help explain aspects of our anatomical evolution and encephalization over the last million years. It will also provide an important perspective on hominin dispersals out of Africa and the colonization of temperate environments, as well as the origins of social developments such as the formation of provi-sioned base camps. Frequencies of burnt flints from a 16-m-deep sequence of archaeological deposits atTabun Cave, Israel, together with data from the broader Levantine archaeological record, demonstratethat regular or habitual fire use developed in the region between 350,000-320,000 years ago. While hominins may have used

fire occasionally, perhaps opportunistically, for some million years, the researchers argue in the paper  that it only became a consistent element in behaviuoral adaptations during the second part of the Middle Pleistocene.

http://www.natureworldnews.com/articles/11176/20141215/humans-first...

Comment by Dr. Krishna Kumari Challa on December 17, 2014 at 7:12am

Merging data on high-energy bursts seen on Earth by NASA's Fermi Gamma-ray Space Telescope with data from ground-based radar and lightning detectors, scientists have completed the most detailed analysis to date of the types of thunderstorms producing terrestrial gamma-ray flashes, or TGFs.
TGFs occur unpredictably and fleetingly, with durations less than a thousandth of a second, and remain poorly understood. Yet the gamma rays they produce rank among the highest-energy light naturally produced on Earth.
Earlier Fermi studies helped uncover lightning-like radio signals emitted by TGFs. This made it possible to use ground-based lightning location networks to pin down storms producing the flashes, opening the door to a deeper understanding of the meteorology powering these extreme events.
Scientists gathered a sample of nearly 900 Fermi TGFs accurately located by ground networks, which can pinpoint the location of lightning discharges -- and the corresponding signals from TGFs -- to within 6 miles (10 km) anywhere on the globe. From this group, they identified 24 TGFs that occurred within areas covered by Next Generation Weather Radar (NEXRAD) sites.
The researchers found that even weak and marginally electrified storms are capable of producing TGFs.
The new study also confirms previous findings indicating that TGFs tend to occur near the highest parts of a thunderstorm, between about 7 and 9 miles (11 to 14 kilometers) high. However, TGFs associated with lightning at lower altitudes would be so weakened by traveling a longer path through the atmosphere that Fermi couldn't detect them. If true, the estimated number of 1,100 TGFs occurring each day may be much larger than previously thought.

Frequent Flyers Could Take a Hit of Radiation from Lightning

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