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Comment by Dr. Krishna Kumari Challa on August 19, 2016 at 7:58am

A black hole analogue, which traps sound instead of light, generates "Hawking radiation," a key prediction by the theoretical physicist. 

Stephen Hawking proposed in 1974 that quantum effects at the event horizon might cause black holes to be…not completely black. 

Recently scientists observed spontaneous Hawking radiation, stimulated by quantum vacuum fluctuations, emanating from an analogue black hole in an atomic Bose–Einstein condensate. Correlations are observed between the Hawking particles outside the black hole and the partner particles inside. These correlations indicate an approximately thermal distribution of Hawking radiation. They found that the high-energy pairs are entangled, while the low-energy pairs are not, within the reasonable assumption that excitations with different frequencies are not correlated. The entanglement verifies the quantum nature of the Hawking radiation. The results are consistent with a driven oscillation experiment and a numerical simulation.

http://www.nature.com/articles/nphys3863.epdf?referrer_access_token...

Comment by Dr. Krishna Kumari Challa on August 18, 2016 at 10:10am

Quantum satellite launch is helping China develop a communications system that ‘cannot be hacked’

Scientists think that using technology harnessing quantum physics is the key to beating electronic snoopers.

China launched the first-ever quantum satellite Monday (Aug. 15) in an effort to help develop an unhackable communications system.

The launch of the world’s first “quantum satellite” is just the beginning of China’s ambitious plans to develop a communications system that cannot be cracked by hackers, according to a lead engineer on the project.

The satellite was launched from the Jiuquan space centre in Gansu province in northwest China this week.

One of the tasks during the satellite’s mission will be to try and send coded communications back to earth that cannot be read by eavesdroppers. How is this possible? High quality Physics!

"Entangled" particles are intimately and curiously linked to each other; even if they're separated by billions of miles of space; a change in one somehow affects the others.

QUESS will send messages to ground stations using entangled photons. Such a system is theoretically impossible to hack. In addition, any attempts to eavesdrop would be picked up via an induced change in the photons' state.

It will attempt to do so by transmitting information through photons, tiny particles found in subatomic or quantum physics.

Researchers believe that information sent through photons cannot be intercepted or analysed by people without the right codes.

The mission to establish a hacker-proof communication link between space and earth requires scientists to carefully adjust the satellite’s position so it can beam single photons on to a targeted area just a few square metres wide on the ground.

They also need to test and fine tune each scientific device on the satellite . Similar ground-based quantum communications systems have also been set up in the US, Europe and Japan, but China has the largest network and is leading the development of the technology in space.

A wiretap splits off a large number of electrons to read the signal and still leaves enough electrons in the line to carry the same signal to the legitimate recipient.

A quantum network, however, carries information by photons and under the law of quantum physics it is impossible to measure their properties without altering them.

If an eavesdropper tries to copy the quantum states, this introduces errors in the transmitted key and gets noticed by the legitimate users.

Some experts think that one possible way of hacking the system a Trojan Horse. It involves firing an extra beam of light at one key part of the communications equipment and light reflected back would carry information processed by the system.

But commercial quantum network applications had been deployed in many countries, but not a single report of a security breach had been reported so far.

China thinks .. To be a quantum hacker you must have a PhD in quantum physics, that’s the minimum requirement. Such a high entry barrier will keep most hackers out of this game.

Comment by Dr. Krishna Kumari Challa on August 18, 2016 at 9:04am

The dodgy academic journals publishing anti-vaxxers and other 'crappy science'
http://www.smh.com.au/national/the-dodgy-academic-journals-publishi...

Comment by Dr. Krishna Kumari Challa on August 17, 2016 at 10:26am

Being Unfit Nearly as Harmful as Smoking!
In a recent study it was found that low levels of aerobic capacity – or being unfit – actually represented a higher death risk than high blood pressure and high cholesterol levels.
Among the risks of a premature death, only smoking cast a longer fatal shadow.
“The advantages of being physically active one’s entire life are crystal clear,” says researcher Per Ladenvall at Salgrenska Academy of the University of Gothenburg.
Why is being in poor physical shape so risky?
“Probably a lot of factors are contributing here. In addition to hypertension and high cholesterol values, those who are in poor shape often have insulin resistance or poor blood sugar regulation. Added to that, they have components in their blood which cause blood clots,” explains Ladenvall.
“They can also have poor resistance against diseases, so that when they fall ill it will more often have a fatal outcome than among persons who are fit,” he adds. Ladenvall works at the University’s Department of Molecular and Clinical Medicine.
The study also found that the better the oxygen uptake the lower the risk of early death among the men. Or to put it simply – they lived longer.

Comment by Dr. Krishna Kumari Challa on August 17, 2016 at 10:25am

Being Unfit Nearly as Harmful as Smoking!

In a recent study it was found that low levels of aerobic capacity – or being unfit – actually represented a higher death risk than high blood pressure and high cholesterol levels.

Among the risks of a premature death, only smoking cast a longer fatal shadow.

“The advantages of being physically active one’s entire life are crystal clear,” says researcher Per Ladenvall at Salgrenska Academy of the University of Gothenburg.

Why is being in poor physical shape so risky?

“Probably a lot of factors are contributing here. In addition to hypertension and high cholesterol values, those who are in poor shape often have insulin resistance or poor blood sugar regulation. Added to that, they have components in their blood which cause blood clots,” explains Ladenvall.

“They can also have poor resistance against diseases, so that when they fall ill it will more often have a fatal outcome than among persons who are fit,” he adds. Ladenvall works at the University’s Department of Molecular and Clinical Medicine.

The study also found that the better the oxygen uptake the lower the risk of early death among the men. Or to put it simply – they lived longer.

Comment by Dr. Krishna Kumari Challa on August 12, 2016 at 9:42am

For the first time scientists can see where molecular tags known as epigenetic marks are placed in the brain.

These chemical tags — which flag DNA or its protein associates, known as histones —don’t change the genes, but can change gene activity. Abnormal epigenetic marks have been associated with brain disorders such as Alzheimer’s disease, schizophrenia, depression and addiction.

Researchers at Massachusetts General Hospital in Boston devised a tracer molecule that latches onto a protein that makes one type of epigenetic mark, known as histone acetylation.

The scientists then used PET scans to detect where a radioactive version of the tracer marked the brains of eight healthy young adult men and women, the researchers report August 10 in Science Translational Medicine. Further studies could show that the marks change as people grow older or develop a disease. The team studied only healthy young volunteers so can’t yet say whether epigenetic marking changes with age or disease.

Comment by Dr. Krishna Kumari Challa on August 10, 2016 at 8:39am

The mighty monsoon winds that periodically bring rains that drench India first billowed around 12.9 million years ago, new research shows. The work provides the best look yet at the conditions that fostered the modern monsoon.

By examining sediments piled up around Indian Ocean islands, researchers uncovered a geologic history of the South Asian monsoon stretching back tens of millions of years. The monsoon winds began abruptly, researchers report online July 20 in Scientific Reports. That speedy start-up suggests that factors such as global cooling were at play in addition to the rise of the Himalayan mountain range, which scientists typically blame for the monsoon’s inception.

Rainfall during the summer monsoon season accounts for more than 70 percent of India’s annual precipitation. The temperature difference between the continent and the adjacent Indian Ocean drives the winds. During winter, warm air over the ocean rises and draws in cool air from the land to the north. In summer, the land becomes warmer and the winds flip direction.

The snow and high elevation of the Himalayas drive the temperature difference between the land and sea. But the mountains grew over tens of millions of years, making it difficult to determine exactly when conditions favorable to the monsoon began. Previous estimates ranged from around 28.7 million to 7 million years ago.

Monsoon winds drive currents in the ocean, which in turn carry ocean sediments across the sea. Sediment accumulates in mounds similar to snowdrifts when currents are strong. The strong currents also pull nutrients from the seafloor toward the surface, boosting biological activity that in turn draws oxygen from the water. That lower oxygen supply leaves a chemical trace in the sediments.

The researchers drilled around 500 meters into the seafloor and extracted sediments dating back roughly 25 million years. A weaker precursor to the modern monsoon existed roughly 25 million years ago, the sediment data suggest. Around 12.9 million years ago, however, the winds revved up to their modern strength over the course of about 300,000 years, a relatively short time compared with the formation of the Himalayas.

The strengthening of the monsoon lines up with a period of global cooling and the growth of the polar ice caps. That climate shift may have boosted the temperature difference between the land and sea, supercharging the winds, the researchers propose.

http://www.nature.com/articles/srep29838

Comment by Dr. Krishna Kumari Challa on August 7, 2016 at 1:27pm

The stimulation hypothesis

Comment by Dr. Krishna Kumari Challa on August 6, 2016 at 5:13am

Carbon Nanotubes: Ultrabreathable and Protective Membranes with Sub-5 nm Carbon Nanotube Pores 

to protect soldiers from biological and chemical threats, a team of Lawrence Livermore National Laboratory scientists has created a material that is highly breathable yet protective from biological agents.

This material is the first key component of futuristic smart uniforms that also will respond to and protect from environmental chemical hazards. The research appears in the July 27 edition of the journal,Advanced Materials 

The LLNL team fabricated flexible polymeric membranes with aligned carbon nanotube (CNT) channels as moisture conductive pores. The size of these pores (less than 5 nanometers, nm) is 5,000 times smaller than the width of a human hair.

To provide high breathability, the new composite material takes advantage of the unique transport properties of carbon nanotube pores. By quantifying the membrane permeability to water vapor, the team found for the first time that, when a concentration gradient is used as a driving force, CNT nanochannels can sustain gas-transport rates exceeding that of a well-known diffusion theory by more than one order of magnitude.

These membranes also provide protection from biological agents due to their very small pore size — less than 5 nanometers (nm) wide. Biological threats like bacteria or viruses are much larger and typically more than 10-nm in size. 

http://onlinelibrary.wiley.com/doi/10.1002/adma.201670197/full

Comment by Dr. Krishna Kumari Challa on August 5, 2016 at 9:13am

Transfer of mitochondria from astrocytes to neurons after stroke

Under duress, nerve cells get a little help from their friends. Brain cells called astrocytes send their own energy-producing mitochondria to struggling nerve cells. Those gifts may help the neurons rebound after injuries such as strokes, scientists propose in the July 28 Nature.

It was known that astrocytes — star-shaped glial cells that, among other jobs, support neurons — take in and dispose of neurons’ discarded mitochondria. Now it turns out that mitochondria can move the other way, too. This astrocyte-to-neuron transfer is surprising.
Mitochondria produce the energy that powers cells in the body. Scientists have spotted the organelles moving into damaged cells in other parts of the body, including the lungs, heart and liver. The new study turns up signs of this mitochondrial generosity in the brain.

Not only do the mitochondria make it into neurons, they actually help. Neurons with donated mitochondria better survived their starvation diet. When grown in dishes without extra mitochondria floating around, neurons were less able to weather the poor conditions, the researchers found.

Further experiments suggest that the transfer happens not just in lab dishes, but in the brains of mice. A day after mice received a strokelike injury, astrocyte-produced mitochondria showed up inside their neurons. The gift giving seems to depend on a protein called CD38, which sits on the outside of astrocytes and may detect distress signals. When CD38 wasn’t functioning, the mice had fewer mitochondria in their neurons. What’s more, the mice were worse at balancing on wires than mice with normal CD38 behavior, a deficit that may be linked to having too few mitochondria in neurons.

The results bolster the idea that mitochondria donations between cells may have tremendous therapeutic potential

http://www.nature.com/nature/journal/v535/n7613/full/nature18928.html

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