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Comment by Dr. Krishna Kumari Challa on December 26, 2014 at 9:44am

A mysterious phase of matter stands in the way of high-temperature superconductivity, new evidence shows

Scientists have just found the first direct evidence that a mysterious phase of matter known as the “pseudogap” is standing in the way of high-temperature superconductivity.
Earlier this month, researchers even managed to acheive the incredible feat of superconductivity at room temperature for the first time ever - but only for (literally) a split second.

Despite the advances, it's always felt as though there was something standing in the way high-temperature superconductivity. And now scientists think they may know what that is - a mysterious phase of matter known as the "pseudogap".
For the past 20 years, researchers at Stanford University and the SLAC National Accelerator Laboratory in the US have been trying to work out whether the pseudogap was helping or hindering high-temperature superconducitivty.

And they've finally found the first direct evidence that this phase of matter steals electrons that would otherwise pair up and allow a material to superconduct.

"Now we have clear, smoking-gun evidence that the pseudogap phase competes with and suppresses superconductivity," said Makoto Hashimoto, the lead author, in a press release. "If we can somehow remove this competition, or handle it better, we may be able to raise the operating temperatures of these superconductors."
The pseudogap was first spotted using a technique called angle-resolved photoemission spectroscopy (or ARPES), which knocks electrons out of a copper oxide material so that researchers can plot their behaviour and then work out how they would behave inside the material.

Researchers have been doing this for decades with copper oxides, one of the very few materials known to display superconductivity at relatively high temperatures of around -135 degrees Celsius.

During superconductivity, electrons leave their usual positions and pair up into something known as Cooper pairs, so that they can conduct electricity with zero resistance and 100 percent efficiency. The researchers were able to see this behaviour using ARPES as a clear gap in their plots of electron behaviour.

But the in the mid-1990s, they discovered another strange gap in their plots of copper oxide. It looked like the “superconducting” gap left by electrons moving into pairs, but it was being seen at temperatures far too high for superconductivity. They called this phase the pseudogap, and have been studying it ever since.

To finally work out what was happening, the team studied not only the energies and momenta of the electrons, but also the number of electrons of particular energies that come out of the material. They tested this over a wide range of temperatures and after altering the electronic properties of the material.

In their experiments, they found strong evidence that at the “transition temperature” of around -135 degrees Celsius, the pseudogap and superconductivity states in copper oxides are competing for electrons. Their results are published in Nature Materials.
http://www.nature.com/nmat/journal/v14/n1/full/nmat4116.html

Comment by Dr. Krishna Kumari Challa on December 26, 2014 at 9:41am

On 27 August 1883, the Earth made the loudest noise in recorded history. Emanating from the island of Krakatoa, which sits between the islands of Java and Sumatra in Indonesia, the sound could be heard clearly almost 5,000 kilometres away and by people across 50 different geological locations around the world.

According to Aatish Bhatia at Nautilus, about 3,200 kilometres away from Krakatoa, residents of New Guinea and Western Australia reported hearing “a series of loud reports, resembling those of artillery in a north-westerly direction”, and over 4,800 kilometres away on the island of Rodrigues in the Indian Ocean, locals reported hearing what sounded to them like the distant roar of heavy gun fire.

The sound was caused by a record-breaking volcanic eruption that sent smoke up almost 80 kilometres into the air as ash fell into the ocean some 20 kilometres away. Burning hot debris was shot from the mouth of Krakatoa's volcano at speeds of up to 2,575 kilometres per hour, which is more than double the speed of sound.
The world's loudest sound caused shock waves 100,000 times that of a hydrogen bomb.
http://nautil.us/blog/the-sound-so-loud-that-it-circled-the-earth-f...

Comment by Dr. Krishna Kumari Challa on December 26, 2014 at 9:31am

Televised medical talk shows—what they recommend and the evidence to support their recommendations: a prospective observational study
BMJ 2014; 349 doi: http://dx.doi.org/10.1136/bmj.g7346 (Published 17 December 2014) Cite this as: BMJ 2014;349:g7346
Abstract

Objective To determine the quality of health recommendations and claims made on popular medical talk shows.

Design Prospective observational study.

Setting Mainstream television media.

Sources Internationally syndicated medical television talk shows that air daily (The Dr Oz Show and The Doctors).

Interventions Investigators randomly selected 40 episodes of each of The Dr Oz Show and The Doctors from early 2013 and identified and evaluated all recommendations made on each program. A group of experienced evidence reviewers independently searched for, and evaluated as a team, evidence to support 80 randomly selected recommendations from each show.

Main outcomes measures Percentage of recommendations that are supported by evidence as determined by a team of experienced evidence reviewers. Secondary outcomes included topics discussed, the number of recommendations made on the shows, and the types and details of recommendations that were made.

Results We could find at least a case study or better evidence to support 54% (95% confidence interval 47% to 62%) of the 160 recommendations (80 from each show). For recommendations in The Dr Oz Show, evidence supported 46%, contradicted 15%, and was not found for 39%. For recommendations in The Doctors, evidence supported 63%, contradicted 14%, and was not found for 24%. Believable or somewhat believable evidence supported 33% of the recommendations on The Dr Oz Show and 53% on The Doctors. On average, The Dr Oz Show had 12 recommendations per episode and The Doctors 11. The most common recommendation category on The Dr Oz Show was dietary advice (39%) and on The Doctors was to consult a healthcare provider (18%). A specific benefit was described for 43% and 41% of the recommendations made on the shows respectively. The magnitude of benefit was described for 17% of the recommendations on The Dr Oz Show and 11% on The Doctors. Disclosure of potential conflicts of interest accompanied 0.4% of recommendations.

Conclusions Recommendations made on medical talk shows often lack adequate information on specific benefits or the magnitude of the effects of these benefits. Approximately half of the recommendations have either no evidence or are contradicted by the best available evidence. Potential conflicts of interest are rarely addressed. The public should be skeptical about recommendations made on medical talk shows.

Comment by Dr. Krishna Kumari Challa on December 26, 2014 at 9:23am

 

Helium becomes superfluid and displays amazing properties.

To address all the comments about helium "running out": Most helium on earth is the result of radioactive decay (alpha particle emission and electron capture) over a very long period of time and is captured in the earth's lithosphere (crust). As such, the helium reserves on earth are finite. The main method of helium extraction is distillation from natural gas which contains up to 7% helium. Worldwide reserves and resources of helium are abundant and at the current rate of extraction will last several centuries.

Comment by Dr. Krishna Kumari Challa on December 26, 2014 at 9:14am

Comment by Dr. Krishna Kumari Challa on December 26, 2014 at 8:34am

Redesigning life

This year saw stunning new developments in the emerging field of synthetic biology. In May, scientists in California explained how they had extended the "alphabet of life". All of the planet's lifeforms use four chemical units, or bases, arranged in pairs within DNA. But the US team modified a an E. coli bug to incorporate two additional chemicals not present in nature. The science could eventually be used to make a range of novel drugs and materials.

The work followed hot on the heels of the announcement that scientists had created the first synthetic chromosome for yeast. The genes in the original chromosome were replaced with synthetic versions. It's hoped the work will enable a range of applications from the manufacture of vaccines to more sustainable forms of biofuel.

Comment by Dr. Krishna Kumari Challa on December 24, 2014 at 8:22am

Some science journals may publish papers after cursory or no peer review, despite claiming otherwise. Researchers may send their papers to predatory journals either knowingly or naively buying into the false claims made.
Find here a list of questionable, scholarly open-access standalone journals

Potential, possible, or probable predatory scholarly open-access journals
http://scholarlyoa.com/individual-journals/
And the list of publishers: Potential, possible, or probable predatory scholarly open-access publishers
http://scholarlyoa.com/publishers/

Find more information here: http://www.scidev.net/global/publishing/practical-guide/target-jour...

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There’s Something Really Wrong With Science These Days

http://brainblogger.com/2014/12/26/theres-something-really-wrong-wi...

Comment by Dr. Krishna Kumari Challa on December 24, 2014 at 8:15am

When somebody loses weight, where does the fat go?
Despite a worldwide obsession with diets and fitness regimes, many health professionals cannot correctly answer the question of where body fat goes when people lose weight. A study published in the British Medical Journal has the surprising answer: we breathe it out.
Where Did The Fat Go? Fat burned during weight loss is breathed out as carbon dioxide and water, but breathing more won’t help you lose weight.
The correct answer is that most of the mass is breathed out as carbon dioxide. It goes into thin air!
In a study and a paper based on their work, the authors show that losing 10 kilograms of fat requires 29 kilograms of oxygen to be inhaled and that this metabolic process produces 28 kilograms of carbon dioxide and 11 kilograms of water.
http://www.bmj.com/content/349/bmj.g7257

Comment by Dr. Krishna Kumari Challa on December 24, 2014 at 8:10am

Equivalence of wave–particle duality to entropic uncertainty
Bridging Two Mysteries At The Heart Of Quantum Physics It turns out that wave-particle duality is simply the quantum uncertainty principle in disguise.
Using novel techniques from information theory, researchers from the National University of Singapore have demonstrated a striking and fundamental relationship between two fundamental characteristics of quantum physics—wave-particle duality and the uncertainty principle. This research, published in Nature Communications, paves the way for more elegant tests of both phenomena in quantum systems. http://www.asianscientist.com/2014/12/in-the-lab/bridging-mysteries...

http://www.nature.com/ncomms/2014/141219/ncomms6814/full/ncomms6814...

Comment by Dr. Krishna Kumari Challa on December 24, 2014 at 7:23am

Clouds may be dining cars for some germs
Germs don’t just hitchhike on clouds, some also treat them as a cafeteria
Researchers have discovered that at least one cloud-dwelling microbe — a bacterium belonging to the Bacillus genus— may dine on sugars while riding the winds in clouds. And this is not just any microbe. It’s one of the types most frequently found in the air and cloud-water droplets, reports a team of European scientists.
Scientists had known for decades that clouds can host diverse communities of microbes. But researchers had suspected those germs, lofted into the air by winds, were just aimlessly hitchhiking rides, sometimes between continents. The new research shows that the germs are not just jetting long distances. Some may treat their cloud ferries like club cars, dining happily as they travel.
https://student.societyforscience.org/article/clouds-may-be-dining-...

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