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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

Comment by Dr. Krishna Kumari Challa on May 5, 2016 at 8:23am

Why are Itches contagious? 

Itching can be "caught" just by watching someone else having a good scratch, scientists have confirmed.

In what is being called itch transmission, scientists have shown that the sensation of an itch can be caught visually in the same way as yawning.

They found that simply watching a video of someone else scratching was enough to induce and intensify itching in volunteers.

Itching becomes contagious because the brain becomes hypersensitive when someone nearby scratches and so misinterprets any kind of physical sensation on our skin as an itch.

The researchers found empathy (a willingness to take another's viewpoint) did not correlate with the phenomenon. Participants who scored high on neuroticism were significantly more likely than others to experience itch contagion, the researchers found. 

There is an evolutionary basis for this mundane behavior.
The world of our Paleolithic ancestors was a pruritogenic wilderness, full of plants and bugs that posed more of a threat than mere skin irritation. So a scratch is a preemptive strike against the more noxious aftereffects if that relatively innocuous warning signal is ignored.

Growing sensitive to itching when one member of the group is scratching could help to identify parasite infestations early and help to stop them spreading.

Comment by Dr. Krishna Kumari Challa on May 4, 2016 at 9:49am

Plastics in Food - Bisphenol A and food safety: Lessons from developed to developing countries

BPA is used to make certain plastics or resins. It can seep into food or drinks from food containers or the protective linings of cans -  
Modern lifestyles and changes in the socio-economic characteristics of households have stimulated current developments in food technology, processing and packaging. Chemicals such as bisphenol A (BPA) are known to migrate from food packaging into the food, resulting in human exposure to these chemicals. Similarly, BPA can migrate from baby feeding bottles into milk. BPA has been associated with adverse effects attributed to its estrogenic properties in various animal models. This review analyzed peer-reviewed publications in the English literature on human BPA exposure and regulations in developing countries compared to developed countries. BPA has been reduced or eliminated from food packaging and contact materials such as baby bottles in developed countries either voluntarily or by legislation. The meager data from developing countries shows that human BPA exposure in developing countries is similar to that in developed countries. With minor exceptions, BPA restriction, voluntary or legal, is virtually absent in developing countries of Africa, SE Asia, and South and Central America.

http://www.sciencedirect.com/science/article/pii/S0278691516300898

Comment by Dr. Krishna Kumari Challa on May 4, 2016 at 9:22am

Biomechanics of the Peacock’s Display: How Feather Structure and Resonance Influence Multimodal Signaling
Courtship displays may serve as signals of the quality of motor performance, but little is known about the underlying biomechanics that determines both their signal content and costs. Peacocks (Pavo cristatus) perform a complex, multimodal “train-rattling” display in which they court females by vibrating the iridescent feathers in their elaborate train ornament. Here we study how feather biomechanics influences the performance of this display using a combination of field recordings and laboratory experiments. Using high-speed video, we find that train-rattling peacocks stridulate their tail feathers against the train at 25.6 Hz, on average, generating a broadband, pulsating mechanical sound at that frequency. Laboratory measurements demonstrate that arrays of peacock tail and train feathers have a broad resonant peak in their vibrational spectra at the range of frequencies used for train-rattling during the display, and the motion of feathers is just as expected for feathers shaking near resonance. This indicates that peacocks are able to drive feather vibrations energetically efficiently over a relatively broad range of frequencies, enabling them to modulate the feather vibration frequency of their displays. Using our field data, we show that peacocks with longer trains use slightly higher vibration frequencies on average, even though longer train feathers are heavier and have lower resonant frequencies. Based on these results, we propose hypotheses for future studies of the function and energetics of this display that ask why its dynamic elements might attract and maintain female attention. Finally, we demonstrate how the mechanical structure of the train feathers affects the peacock’s visual display by allowing the colorful iridescent eyespots–which strongly influence female mate choice–to remain nearly stationary against a dynamic iridescent background.
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.01...

Comment by Dr. Krishna Kumari Challa on May 3, 2016 at 6:48am

Comment by Dr. Krishna Kumari Challa on April 30, 2016 at 9:12am

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