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Comment by Dr. Krishna Kumari Challa on June 3, 2016 at 10:41am

New 'Einstein ring' discovered
The PhD student Margherita Bettinelli, of the Instituto de Astrofísica de Canarias (IAC) and the University of La Laguna (ULL), together with an international team of astrophysicists has recently discovered an unusual astronomical object: an Einstein ring. These phenomena, predicted by Einstein's theory of General Relativity, are quite rare but scientifically interesting. The interest is sufficiently strong that this object has been given its own name: the "The Canarias Einstein ring". The research was carried out by the Stellar Populations group at the IAC, led by Antonio Aparicio and Sebastian Hidalgo. The results were published in the international journal Monthly Notices of the Royal Astronomical Society.
An Einstein ring is a distorted image of a verydistant galaxy, which is termed "the source". The distortion is produced by the bending of the light rays from the source due to amassive galaxy, termed "the lens", lying between it and the observer. The stronggravitational field produced by the lens galaxy distorts the structure of space-time in its neighbourhood, and this does not only attract objects which have a mass, but also bends the paths of light. When the two galaxies are exactly aligned, the image of the more distant galaxy is converted into an almost perfect circle which surrounds the lens galaxy. The irregularities in the circle are due to asymmetries in the source galaxy.
This "Canarias Einstein ring" is one of the most symmetrical discovered until now and is almost circular, showing that the two galaxies are almost perfectly aligned, with a separation on the sky of only 0.2 arcseconds. The source galaxy is 10,000 million light years away from us. Due to the expansion of the Universe, this distance was smaller when its light started on its journey to us, and has taken 8,500 million years to reach us. We observe it as it was then: a blue galaxy which is beginning to evolve, populated by young stars which are forming at a high rate. The lens galaxy is nearer to us, 6,000 million light years away, and is more evolved. Its stars have almost stopped forming, and its population is old.

Comment by Dr. Krishna Kumari Challa on May 31, 2016 at 6:20am

Invisible waves move materials within aquatic ecosystems
Garbage, nutrients and tiny animals are pushed around, suspended in the world's oceans by waves invisible to the naked eye according to a new 3-D model developed by mathematicians at the University of Waterloo.

David Deepwell, a graduate student, and Professor Marek Stastna in Waterloo's Faculty of Mathematics have created a 3-D simulation that showcases how materials such phytoplankton, contaminants, and nutrients move within aquatic ecosystems via underwater bulges called mode-2 internal waves.

The simulation can help researchers understand how internal waves can carry materials over long distances. Their model was presented in the American Institute of Physics' journal Physics of Fluids earlier this week.

In the simulation, fluids of different densities are layered like the layers of a cake, creating an environment similar to that found in large aquatic bodies such as oceans and lakes. A middle layer of fluid, known as a pycnocline, over which the layers are closely packed together is created, and it is in this layer that materials tend to be caught.
When the fluid behind the gate is mixed and then the gate is removed, the mixed fluid collapses into the stratification because it is both heavier than the top layer and lighter than the bottom one.

Adding dye to the mixed fluid while the gate is in place simulates the material we want the mode-2 waves - the bulges in the pycnocline formed once the gate is taken away - to transport. We can then measure the size of the wave, how much dye remains trapped within it, and how well the wave carries its captured material.

It was found that the larger the bulge within the pycnocline, the larger the amount of material carried by the mode-2 wave.

While the researchers have discovered an optimal scenario in which the mode-2 internal wave survives and then transports material for as long a distance as possible, the internal waves can also break down due to small regions of instability, called lee instabilities, that form behind the wave. When the mode-2 wave breaks down, material is lost behind the wave. Ongoing experimental work and simulations are exploring how this type of wave interacts with underwater topography like sea mounts.

Comment by Dr. Krishna Kumari Challa on May 28, 2016 at 9:00am

Alzheimer’s and Infection connection?
New research by a team of investigators at Harvard leads to a startling hypothesis, which could explain the origins of plaque, the mysterious hard little balls that pockmark the brains of people with Alzheimer’s.
The idea that infections, including ones that are too mild to elicit symptoms, may produce a fierce reaction that leaves debris in the brain, causing Alzheimer’s. If it holds up, the hypothesis has major implications for preventing and treating this degenerative brain disease.
This is how it happens...
virus, fungus or bacterium gets into the brain, passing through a membrane — the blood-brain barrier — that becomes leaky as people age. The brain’s defense system rushes in to stop the invader by making a sticky cage out of proteins, called beta amyloid. The microbe, like a fly in a spider web, becomes trapped in the cage and dies. What is left behind is the cage — a plaque that is the hallmark of Alzheimer’s.

So far, the group has confirmed this hypothesis in neurons growing in petri dishes as well as in yeast, roundworms, fruit flies and mice. There is much more work to be done to determine if a similar sequence happens in humans, but plans — and funding — are in place to start those studies, involving a multicenter project that will examine human brains.

http://stm.sciencemag.org/content/8/340/340ra72

Comment by Dr. Krishna Kumari Challa on May 28, 2016 at 5:40am

There is a fight between cell phone lobby and other scientists working in the area. While the former say cell phones are safe, the latter have a different view on it.
Now a new study reignites the question and says ... Exposure to radio-frequency radiation of cell phones are responsible for tumor formation in rats in their experiments.

 http://biorxiv.org/content/biorxiv/early/2016/05/26/055699.full.pdf

US Federal scientists released partial findings Friday from a $25-million animal study that tested the possibility of links between cancer and chronic exposure to the type of radiation emitted from cell phones and wireless devices. The findings, which chronicle an unprecedented number of rodents subjected to a lifetime of electromagnetic radiation starting in utero, present some of the strongest evidence to date that such exposure is associated with the formation of rare cancers in at least two cell types in the brains and hearts of rats.

They chronically exposed rodents to carefully calibrated radio-frequency (RF) radiation levels designed to roughly emulate what humans with heavy cell phone use or exposure could theoretically experience in their daily lives. The animals were placed in specially built chambers that dosed their whole bodies with varying amounts and types of this radiation for approximately nine hours per day throughout their two-year life spans. “This is by far—far and away—the most carefully done cell phone bioassay, a biological assessment. This is a classic study that is done for trying to understand cancers in humans.

The researchers found that as the thousands of rats in the new study were exposed to greater intensities of RF radiation, more of them developed rare forms of brain and heart cancer that could not be easily explained away, exhibiting a direct dose–response relationship. Overall, the incidence of these rare tumors was still relatively low, which would be expected with rare tumors in general, but the incidence grew with greater levels of exposure to the radiation. Some of the rats had glioma—a tumor of the glial cells in the brain—or schwannoma  of the heart. Furthering concern about the findings: In prior epidemiological studies of humans and cell phone exposure, both types of tumors have also cropped up as associations.

In contrast, none of the control rats—those not exposed to the radiation—developed such tumors. But complicating matters was the fact that the findings were mixed across sexes: More such lesions were found in male rats than in female rats. The tumors in the male rats “are considered likely the result of whole-body exposure” to this radiation, the study authors wrote. And the data suggests the relationship was strongest between the RF exposure and the lesions in the heart, rather than the brain: Cardiac schwannomas were observed in male rats at all exposed groups, the authors note. But no “biologically significant effects were observed in the brain or heart of female rats regardless of modulation.” 

Now what should you do? Take a few precautions...here are safety steps individuals can take: Using the speakerphone, keeping the phone on the desk instead of on the body and using a wired headset whenever possible would help limit RF exposure. Reduce the exposure as much as possible.

 

http://blogs.scientificamerican.com/guest-blog/it-s-premature-to-co...

http://blogs.scientificamerican.com/guest-blog/do-cell-phones-cause...

Comment by Dr. Krishna Kumari Challa on May 28, 2016 at 5:20am

A Fifth Force of Nature?
A laboratory experiment in Hungary has spotted an anomaly in radioactive decay that could be the signature of a previously unknown fifth fundamental force of nature, physicists say—if the finding holds up.
Attila Krasznahorkay at the Hungarian Academy of Sciences’s Institute for Nuclear Research in Debrecen, Hungary, and his colleagues reported their surprising result in 2015 on the arXiv preprint server, and this January in the journal Physical Review Letters. But the report – which posited the existence of a new, light boson only 34 times heavier than the electron—was largely overlooked.
Again on April 25, a group of US theoretical physicists brought the finding to wider attention by publishing its own analysis of the result on arXiv. The theorists showed that the data didn’t conflict with any previous experiments—and concluded that it could be evidence for a fifth fundamental force. Researchers there were sceptical but excited about the idea.
Gravity, electromagnetism and the strong and weak nuclear forces are the four fundamental forces known to physics—but researchers have made many as-yet unsubstantiated claims of a fifth. Over the past decade, the search for new forces has ramped up because of the inability of the standard model of particle physics to explain dark matter—an invisible substance thought to make up more than 80% of the Universe’s mass. Theorists have proposed various exotic-matter particles and force-carriers, including “dark photons”, by analogy to conventional photons that carry the electromagnetic force.
Krasznahorkay says his group was searching for evidence of just such a dark photon – but Feng’s team think they found something different. The Hungarian team fired protons at thin targets of lithium-7, which created unstable beryllium-8 nuclei that then decayed and spat out pairs of electrons and positrons. According to the standard model, physicists should see that the number of observed pairs drops as the angle separating the trajectory of the electron and positron increases. But the team reported that at about 140º, the number of such emissions jumps—creating a ‘bump’ when the number of pairs are plotted against the angle—before dropping off again at higher angles.

Krasznahorkay says that the bump is strong evidence that a minute fraction of the unstable beryllium-8 nuclei shed their excess energy in the form of a new particle, which then decays into an electron–positron pair. He and his colleagues calculate the particle’s mass to be about 17 megaelectronvolts (MeV).

 https://arxiv.org/abs/1504.01527

http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.042501

Comment by Dr. Krishna Kumari Challa on May 25, 2016 at 7:06am

According to new calculations, Earth’s center is more than two years younger than its surface!
How is this possible?
In Einstein’s general theory of relativity, massive objects warp the fabric of spacetime, creating a gravitational pull and slowing time nearby. So a clock placed at Earth’s center will tick ever-so-slightly slower than a clock at its surface. Such time shifts are determined by the gravitational potential, a measure of the amount of work it would take to move an object from one place to another. Since climbing up from Earth’s center would be a struggle against gravity, clocks down deep would run slow relative to surface timepieces.

Over the 4.5 billion years of Earth’s history, the gradual shaving off of fractions of a second adds up to a core that’s 2.5 years younger than the planet’s crust, researchers estimate in the May European Journal of Physics.

The new calculation neglects geological processes, which have a larger impact on the planet’s age. For example, Earth’s core probably formed earlier than its crust. Instead, says study author Ulrik Uggerhøj of Aarhus University in Denmark, the calculation serves as an illustration of gravity’s influence on time — very close to home.

U. I. Uggerhoj, R. E. Mikkelsen, and J. Faye. The young centre of the Earth. European Journal of Physics. Vol. 37 May 2016, p. 035602. doi: 10.1088/0143-0807/37/3/035602.

The young centre of the Earth

http://iopscience.iop.org/article/10.1088/0143-0807/37/3/035602

Comment by Dr. Krishna Kumari Challa on May 25, 2016 at 6:49am

Attention deficit hyperactivity disorder (ADHD), usually diagnosed in children, may show up for the first time in adulthood, two recent studies suggest.
And not only can ADHD appear for the first time after childhood, but the symptoms for adult-onset ADHD may be different from symptoms experienced by kids, the researchers found.
Although the nature of symptoms differs somewhat between children and adults, all age groups show impairments in multiple domains – school, family and friendships for kids and school, occupation, marriage and driving for adults.
However, some newly diagnosed adults might have had undetected ADHD as children. Support from parents and teachers or high intelligence, for example, might prevent ADHD symptoms from emerging earlier in life.

And these people should take immediate medical assistance to alleviate their problems.

Comment by Dr. Krishna Kumari Challa on May 21, 2016 at 5:21am

Dust storms: Dust is a powerful, but invisible, force. It shapes Earth’s environment in ways that few people realize. Every year, three to four billion tons of dust is lifted into the air around the world by wind. That’s enough to cover a city of moderate area to a depth of 5 meters (16 feet).
Once airborne, this dust can travel thousands of kilometers. It nourishes some of our planet’s largest and lushest forests — allowing them to grow where otherwise they could not. It triggers rain and snowfall. It may even ferry diseases across oceans.

British and American Scientists have been trying to figure this out for half a century, ever since someone accidentally discovered how far dust can travel. Researchers are finding tiny amounts of several elements — sodium, potassium and calcium — in the air just above the ocean. They thought it came from tiny bits of salt lofted up from seawater as bubbles burst on the ocean’s surface.

But soon discovered the elements didn’t come from salt.The mud was from the bottom of the ocean, often from a depth of more than 3,000 meters (about 10,000 feet). Some samples had come from parts of the ocean that were thousands of kilometers from land. They were all cluttered with tiny flecks of crystals — minerals known as quartz and mica. These minerals were known to form on land, not in the sea. The minerals on the sea floor and the sodium, potassium and calcium in the air above the water were coming from the same source: tiny grains of dust. That dust might ride the winds for thousands of kilometers before finally settling down onto the ocean. If true, it would mean that 30 to 80 percent of the mud on the sea floor actually came from distant lands!

And they found that this dust is coming from deserts like Sahara! Around 30 billion kilograms (33 million tons) of Saharan dust flew over the Atlantic Ocean toward Barbados each year. For much of the year, dust from the Sahara drifts toward the Caribbean and southeastern United States. But winds shift during the winter. Then they began carrying Bodélé dust a different way over the Atlantic Ocean. When it reaches South America, on the other side, it does something truly amazing.

Comment by Dr. Krishna Kumari Challa on May 11, 2016 at 6:17am

Climate change may contribute to rising rates of chronic kidney disease
Chronic kidney disease that is not associated with traditional risk factors appears to be increasing in rural hot communities as worldwide temperature progressively rises. The condition has likely increased due to global warming and an increase in extreme heat waves, and it is having a disproportionate impact on vulnerable populations, say investigators.
Climate change may be accelerating rates of chronic kidney disease caused by dehydration and heat stress, according to research appearing in an upcoming issue of the Clinical Journal of the American Society of Nephrology (CJASN). The findings suggest that a condition called heat stress nephropathy may represent a disease of neglected populations, but one that may emerge as a major cause of poor kidney health in the near future.
Over the next century, climate change and resulting water shortages are likely to affect a wide variety of health issues related to dehydration and heat stress -- with risks increasing for cognitive dysfunction, malnutrition, water-borne infectious diseases, chronic kidney disease, and other conditions.
Reports of heat stress nephropathy -- or chronic kidney disease consistent with heat stress -- that are already occurring throughout the world.

The investigators found that chronic kidney disease that is not associated with traditional risk factors appears to be increasing in rural hot communities as worldwide temperature progressively rises. They believe the risk for heat stress nephropathy has increased due to global warming and an increase in extreme heat waves, and it is having a disproportionate impact on vulnerable populations, such as agricultural workers. Decreasing precipitation exacerbates this epidemic by reducing the water supply and water quality as temperatures climbs.

The researchers recommend that governments and scientists work together to conduct epidemiological and clinical studies to document the presence of these epidemics and their magnitude. Interventions are also needed to improve worksite conditions and ensure adequate hydration.

Climate change has led to significant rise of 0.8°C–0.9°C in global mean temperature over the last century and has been linked with significant increases in the frequency and severity of heat waves (extreme heat events). Climate change has also been increasingly connected to detrimental human health. One of the consequences of climate-related extreme heat exposure is dehydration and volume loss, leading to acute mortality from exacerbations of pre-existing chronic disease, as well as from outright heat exhaustion and heat stroke. Recent studies have also shown that recurrent heat exposure with physical exertion and inadequate hydration can lead to CKD that is distinct from that caused by diabetes, hypertension, or GN. Epidemics of CKD consistent with heat stress nephropathy are now occurring across the world. Here, we describe this disease, discuss the locations where it appears to be manifesting, link it with increasing temperatures, and discuss ongoing attempts to prevent the disease. Heat stress nephropathy may represent one of the first epidemics due to global warming. Government, industry, and health policy makers in the impacted regions should place greater emphasis on occupational and community interventions.
http://cjasn.asnjournals.org/content/early/2016/05/04/CJN.13841215

Comment by Dr. Krishna Kumari Challa on May 10, 2016 at 7:53am

Medical error—the third leading cause of death! That too in developed countries!
Medical errors the third leading cause of death, only after heart disease and cancer.

Lab test failures contribute to delayed or wrong diagnoses and unnecessary costs and care. Most people will experience at least one diagnostic error in their life. Errors related to lab tests are more common than you might think.

Misperceptions that diagnostic laboratory tests are always correct and useful exist even though experts say ‘no test performs perfectly’.

Whether due to misuse or a failure mode, all lab tests have limitations. Some of the most common reasons include mistakes in ordering lab tests—meaning the right tests are not ordered at the right time—and problems with the accuracy, availability, and interpretation of their results.

From a patient’s perspective the best thing you can do to overcome lab test-related errors is be informed about the possible problems that could arise and what to ask to try to avoid them.

http://www.bmj.com/content/bmj/353/bmj.i2139.full.pdf

                                         0099--0099

The cost of poor blood specimen quality and errors in preanalytical processes

Preanalytical phase errors may account for 75% of total laboratory errors.

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One failure can affect patient treatment and multiply into significant costs.

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A model can estimate the cost of poor specimen quality on total operating costs.

http://www.sciencedirect.com/science/article/pii/S0009912013002786

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