Comment

Comment by Dr. Krishna Kumari Challa on August 19, 2015 at 8:55am

Abrupt changes in Indian summer monsoon strength during 33,800 to 5500 years B.P.
Abstract

Speleothem proxy records from northeastern (NE) India reflect seasonal changes in Indian summer monsoon strength as well as moisture source and transport paths. We have analyzed a new speleothem record from Mawmluh Cave, Meghalaya, India, in order to better understand these processes. The data show a strong wet phase 33,500–32,500 years B.P. followed by a weak/dry phase from 26,000 to 23,500 years B.P. and a very weak phase from 17,000 to 15,000 years B.P. The record suggests abrupt increase in strength during the Bølling-Allerød and early Holocene periods and pronounced weakening during the Heinrich and Younger Dryas cold events. We infer that these changes in monsoon strength are driven by changes in temperature gradients which drive changes in winds and moisture transport into northeast India.

http://onlinelibrary.wiley.com/doi/10.1002/2015GL064015/abstract

Comment by Dr. Krishna Kumari Challa on August 19, 2015 at 8:44am

Acoustic stealth - this is what gives owls an edge over their prey...
A new study says ... Owls are equipped with state-of-the-art stealth technology to help them swoop on prey undetected.
The night hunters have feathers that absorb aerodynamic sound and suppress the vibrations that occur when a bird flaps its wings.

During flight, an owl’s feathers extract mechanical energy and convert it into heat. The result is perfect silence as the bird approaches to within inches of a mouse or vole.
Scientists used lasers and high-speed cameras to analyse and compare long-eared owl, eagle, and pigeon feathers during flight.
While differing in size, all three birds have a similar “flapping” style.

Lead researcher Jinkui Chu, from Dalian University of Technology in China, said: “Many owls have a unique and fascinating ability to fly so silently that they are out of their prey’s hearing range, due to their feather structure.

“This behaviour has long been of interest to engineers, as we seek to apply the owl’s noise-reduction mechanisms to other purposes and situations that benefit society.

“Now, however, we know the owls’ silent flight ability is even more superior than we thought.

“You could say of all birds it is the ‘king of acoustic stealth’. It not only manages to suppress aerodynamic noise when gliding, but also mechanical noise caused by vibration during flying.

“This is remarkable, considering the sudden jumping, bending and twisting the wings are subjected to when flapping and the noise that creates for other birds.

“In the scientific world, the process used to eliminate this mechanical noise is called ’damping’ — which means the extraction of mechanical energy from a vibrating system usually by converting it into heat and allowing it to remain steady.”

Comment by Dr. Krishna Kumari Challa on August 18, 2015 at 8:42am

Whistled Turkish alters language asymmetries
Whistled languages represent an experiment of nature to test the widely accepted view that language comprehension is to some extent governed by the left hemisphere in a rather input-invariant manner. Indeed, left-hemisphere superiority has been reported for atonal and tonal languages, click consonants, writing and sign languages. The right hemisphere is specialized to encode acoustic properties like spectral cues, pitch, and melodic lines and plays a role for prosodic communicative cues. Would left hemisphere language superiority change when subjects had to encode a language that is constituted by acoustic properties for which the right hemisphere is specialized? Whistled Turkish uses the full lexical and syntactic information of vocal Turkish, and transforms this into whistles to transport complex conversations with constrained whistled articulations over long distances . The comprehension of vocally vs. whistled identical lexical information in native whistle-speaking people of mountainous Northeast Turkey has been tested in this study. It was found that that whistled language comprehension relies on symmetric hemispheric contributions, associated with a decrease of left and a relative increase of right hemispheric encoding mechanisms. The results demonstrate that a language that places high demands on right-hemisphere typical acoustical encoding creates a radical change in language asymmetries. Thus, language asymmetry patterns are in an important way shaped by the physical properties of the lexical input.

http://www.cell.com/current-biology/abstract/S0960-9822%2815%2900794-0

Comment by Dr. Krishna Kumari Challa on August 16, 2015 at 9:37am

New type of glass produced...
When Prof. Juan de Pablo and his collaborators set about to explain unusual peaks in what should have been featureless optical data, they thought there was a problem in their calculations. In fact, what they were seeing was real. The peaks were an indication of molecular order in a material thought to be entirely amorphous and random: Their experiments had produced a new kind of glass.
Their unforeseen discovery, reported in a paper published in the Proceedings of the National Academy of Sciences and chosen by Science as an editor's choice paper in Materials Science, could offer a simple way to improve the efficiency of electronic devices such as light-emitting diodes, optical fibers and solar cells. It also could have important theoretical implications for understanding the still surprisingly mysterious materials called glasses.

The scientists grew the glass by vaporizing large organic molecules in a high vacuum and depositing them slowly, thin layer by thin layer, onto a substrate at a precisely controlled temperature. When the sample was thick enough, they analyzed it using spectroscopic ellipsometry—a technique that measures the way incident light or laser radiation interacts with the material being investigated.
The answer, the scientists discovered, lay in the way the material was created. In liquids—and glass is a type of liquid—the molecules at the surface interact with molecules in the air, sometimes causing them to pack together and line up differently than the randomly arrayed molecules in the bulk of the liquid. The vapor deposition process used in the experiments amounts to laying down one "surface" on top of another. The molecules in each layer get "trapped" in the orientation they had when they were truly, however briefly, on the surface.

In order for this to happen, the researchers discovered, the glass must be grown within the relatively narrow temperature range at which a liquid changes into a solid-like glass. Varying the temperature within that window allows the scientists to "tune" the degree of order. Once the deposition process is finished, the material is stable and changing temperatures within a wide range doesn't affect it.

Only a small fraction of the molecules in the group's samples are oriented in a different direction than the rest of the glass molecules. But that is enough to change the optical properties of these materials tremendously. The group will continue to investigate these new materials, trying different molecules and looking to find out if they can enhance the effect.

A theoretical investigation of these findings also awaits.

http://phys.org/news/2015-08-molecular-scientists-unexpectedly-glas...

Comment by Dr. Krishna Kumari Challa on August 16, 2015 at 9:12am

Australian researchers have developed a nano-sized capsule that can be delivered to a patient intravenously to immediately target and break down the blot clots that cause heart attacks and strokes.

No only does the minuscule device start working within minutes, it’s portable, which means it can be used in emergency situations before the patient has even made it to hospital. "This can be given in the ambulance straight away so you really save a lot of time and restore the blood flow to the critical organs much faster than currently possible".
Around 80 percent of all strokes occur when a fatty deposit or blood clot blocks an artery that supplies blood to the brain. If this formation of blood clots, known as thrombosis, happens to block blood flow to the heart, a heart attack can follow. The longer the brain or heart are without oxygenated blood, the greater the risk that vital tissues will begin to die, so breaking down these clots as soon as possible is key.

If the team can get their device commercialised, it’s set to make a huge difference to the many heart attack and stoke patients who don’t actually respond to current treatments.
The new nanocapsule device only releases the medication in areas where a clot is growing exponentially and blocking a vessel and doesn't have the side effect of unnecessary internal bleeding. "The drug-loaded nanocapsule is coated with an antibody that specifically targets activated platelets, the cells that form blood clots.""
"Once located at the site of the blood clot, thrombin - a molecule at the centre of the clotting process - breaks open the outer layer of the nanocapsule, releasing the clot-busting drug. We are effectively hijacking the blood clotting system to initiate the removal of the blockage in the blood vessel."
http://newsroom.melbourne.edu/news/new-clot-busting-treatment-targe...
New clot-busting treatment targets number one killer

Comment by Dr. Krishna Kumari Challa on August 16, 2015 at 8:24am

Comment by Dr. Krishna Kumari Challa on August 16, 2015 at 7:42am

The International Astronomical Union (IAU) published their official definition of what constitutes a planet in this memo: https://www.iau.org/static/resol... in 2006. In short, it said that:

1) a planet directly orbits the Sun. That excludes moons because although they indirectly orbit the Sun, they directly orbit a planet.

2) a planet is massive enough that gravity overcomes rigid body forces and results in a round, almost spherical shape. That excludes the asteroids.

3) a planet has used its mass to sweep up the trash in its neighborhood.

Comment by Dr. Krishna Kumari Challa on August 14, 2015 at 7:27am

A new study showing that women have slightly lower resting metabolic rates than men, and thus have a higher temperature at which they are most comfortable is proving a gender bias in offices. The study’s authors contend that current methods for designing air conditioning systems do not take this metabolic difference into account. The study argues for changes in air conditioning design standards, but differences in resting metabolic rate have little to do with why women are cold in the office. It has far more to do with who sets the thermostat than with metabolism differences or system design.
Buildings are generally designed to meet standard guidelines for heating and cooling. The building’s ability to keep us cool is based on a series of complex equations that take into account humidity, air temperature, airflow, radiant temperature and the metabolism of the humans theoretically present.

But these complex equations are based on a single metabolic average, says Boris Kingma, a biophysicist at Maastricht University Medical Center in the Netherlands — the average metabolic rate of a 40-year-old man who weighs 70 kilograms, or about 154 pounds.
The women had an average resting metabolic rate of 48 watts per square meter, significantly lower than the average used to calculate heating and cooling needs in buildings. Women are also comfortable at higher temperatures — between 23° and 26° Celsius (or 74° and 79° Fahrenheit) — than those previously calculated. Kingma and coauthor Wouter van Marken Litchenbelt reported their findings August 3 in Nature Climate Change.
http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate2...

Comment by Dr. Krishna Kumari Challa on August 14, 2015 at 6:59am

Comment by Dr. Krishna Kumari Challa on August 14, 2015 at 6:34am

Good news for smokers who want to quit: nicotine addiction therapy.

with Nicotine-Chomping Bacteria

Researchers isolated a bacterial enzyme that could break down nicotine before smokers get the buzz that keeps them coming back for more.

A New Strategy for Smoking Cessation: Characterization of a Bacterial Enzyme for the Degradation of Nicotine

http://pubs.acs.org/doi/abs/10.1021/jacs.5b06605

The nicotine-degrading enzyme NicA2, a flavin-containing protein produced by Pseudomonas putida. When it was added the enzyme to mouse serum, doped with a cigarette's worth of nicotine, (the enzyme was stable at human body temperature) was able to cut the half-life of nicotine from a couple hours to less than 15 minutes—that is, it greatly accelerated nicotine’s disappearance.

But the enzyme isn't ready for use yet. It's bacterial—so "you're going to get an immune response, immune surveillance from it." And right now, the other important half-life, that of the enzyme in serum, is only 3 days. So it won’t stick around long enough to be an effective vaccine.

These problems still have to be solved.

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