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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

Comment by Dr. Krishna Kumari Challa on April 30, 2016 at 6:07am

Recent research by scientists at University of Florida and Union College in Lincoln, found that bed bugs strongly prefer harbourages (places of shelter) that are red and black, and they seemed to avoid colours like green and yellow. The researchers also found that the bed bugs prefer different colours depending on their sex, appetite and whether they were alone or not. These colour preferences could potentially be used in the future to help to develop more intricate and effective traps.

Chromophobia is the fear of, or aversion to, certain colours.
http://jme.oxfordjournals.org/content/early/2016/04/20/jme.tjw033

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The standard model of particle physics, the quantum-theory-based melange that bundles up our knowledge of all the forces of nature besides gravity. One of its revelations is that every fundamental matter particle has an antimatter twin – a particle identical in every way apart from having the opposite electric charge. For the familiar negatively charged electron there is a positively charged “positron”, and so on.

The big bang should have made equal amounts of matter and antimatter. But here’s the thing: when matter and antimatter meet, they annihilate in a puff of energy. So neither should have survived the early days of the universe.

Yet one of them did. Various experiments have tried to find some mismatch between processes involving matter and antimatter to explain this. The latest is LHCb at the CERN particle physics lab, which is looking for an imbalance in decays of particles known as mesons, made up of a quark and an antiquark.

Comment by Dr. Krishna Kumari Challa on April 29, 2016 at 10:16am

Reasons for dry mouth feeling
The origin of astringent mouthfeel when we eat unripe fruits, drink coffee or tea, from the perspective of lubrication by simulating the dynamic weak interaction on the tongue with model protein (mucoprotein, MP) and polyphenolic compounds (tannic acid, TA). Astringency was due to the protein-mediated lubrication failure when encountering polyphenolic molecules that normally exist, for example in unripe fruits, coffee, tea. The underlying molecular mechanism of oral tribology is widely present in nature and enables us to engineer a tongue-like polyacrylamide composite hydrogel that exhibits high TA sensitivity and to develop a scientific strategy for catching slippery fish using TA-containing gloves. These results provide novel and useful insights into the failure of biological boundary lubrication on soft tissue surface with the adsorbed proteins.
( That strange feeling in the mouth after a sip of red wine or tea, or a bite of unripe fruit. It has been described as dry, leathery or even furry. This astringent effect is caused by tannins or polyphenolic compounds that bind to mucins, lubricating proteins in the mucus membranes of the mouth. Now, in the journal Angewandte Chemie, a Chinese and Korean research team has described the relationship between astringency and this disrupted oral lubrication. Mucins consist of a central protein chain with side chains made of sugar compounds that can bind a large amount of water. Mucins form a barrier and protect sensitive mucus membranes from drying out and from chemical and mechanical interactions. They provide adequate lubrication and correspondingly low friction. This lubricating film in the oral cavity fails when tannins come in: a sip of wine causes the tongue to feel less slippery).
They found that when the tannic acid binds to the mucin, their interactions reduce the solubility of the protein in water. The mucins consequently aggregate and may precipitate, leading to a failure of the mucin lubrication film. Under a miscroscope, a substrate coated in mucin showed a flat, dense, film. After addition of tannic acid, many “defects” could be seen in the film and the surface was significantly rougher. In comparison to a glass surface coated only with water, mucin-coated glass had much lower friction when coming into contact with a soft plastic ball. Addition of tannic acid caused the friction to rise substantially. An extract of coffee beans, which also contain tannins, had a similar effect. Finally, in order to mimic a tongue, the scientists produced a mucin-containing plastic hydrogel. When wet, this elastic but barely tear-resistant material had very low friction, slipping easily through the fingers. A weight placed on an inclined surface of this hydrogel slides right off. Addition of a tannic acid solution makes the gel sticky and it begins to shrink as a result of losing water. The mechanical strength increases significantly and the elasticity decreases; the weight no longer slides off.
This finding may guide people to change their eating habits. For example, protein-rich and polyphenol-rich foods can’t be eaten together.
Astringent Mouthfeel as a Consequence of Lubrication Failure
http://onlinelibrary.wiley.com/doi/10.1002/anie.201601667/abstract;...

Comment by Dr. Krishna Kumari Challa on April 29, 2016 at 9:14am

Q: Why can't we send the satellites whose tenure is over into deep space instead of burning them up in the atmosphere?

A: Climbing out of a gravity well is tough.  It takes a lot of energy and that means it takes a lot of propellant.

It took about 40 Space Shuttle flights and several Russian Proton rockets to lift all of the hardware of ISS into low Earth orbit.  Lifting the assembled stack from LEO to beyond geosynchronous orbit would require about half as much energy again.

That much energy cannot be stored within the ISS.  It would have to be provided by a series of Russian Progress vehicles.  The problem with that is that each mile or kilometer the ISS rises makes it harder for a Progress to get to the ISS.  The Progress is only certified to fly to an altitude of 460 km (286 miles).

That means we simply don't have the technology, today, to move the ISS that high.

And if we did move it that high, it would become an out of control hunk of metal.  The ISS was designed for low Earth orbit.  Its  communication and navigation equipment  depend on being able to look up at satellites.  It would serve no value other than being preserved so that people a few hundred years from now could visit it.

The cost to develop the technology to accomplish the move and the cost of executing the move would be great.  It is not realistic to expect our legislatures to pay for such a thing.  And if they did, it would likely be in lieu of going to Mars or returning to the Moon or whatever the next great adventure will be.  Preserving the past would prevent the future.

Comment by Dr. Krishna Kumari Challa on April 29, 2016 at 6:28am

A New State of the Water Molecule found

Neutron scattering and computational modeling have revealed unique and unexpected behavior of water molecules under extreme confinement that is unmatched by any known gas, liquid or solid states.
Researchers at the Department of Energy's Oak Ridge National Laboratory describe a new tunneling state of water molecules confined in hexagonal ultra-small channels - 5 angstrom across - of the mineral beryl. An angstrom is 1/10-billionth of a meter, and individual atoms are typically about 1 angstrom in diameter.

The discovery, made possible with experiments at ORNL's Spallation Neutron Source and the Rutherford Appleton Laboratory in the United Kingdom, demonstrates features of water under ultra confinement in rocks, soil and cell walls, which scientists predict will be of interest across many disciplines.

At low temperatures, this tunneling water exhibits quantum motion through the separating potential walls, which is forbidden in the classical world, according to the scientists. This means that the oxygen and hydrogen atoms of the water molecule are 'delocalized' and therefore simultaneously present in all six symmetrically equivalent positions in the channel at the same time. It's one of those phenomena that only occur in quantum mechanics and has no parallel in our everyday experience.

The existence of the tunneling state of water shown in ORNL's study should help scientists better describe the thermodynamic properties and behavior of water in highly confined environments such as water diffusion and transport in the channels of cell membranes, in carbon nanotubes and along grain boundaries and at mineral interfaces in a host of geological environments.

This discovery represents a new fundamental understanding of the behavior of water and the way water utilizes energy.

The experiments showed that, in the tunneling state, the water molecules are delocalized around a ring so the water molecule assumes an unusual double top-like shape.

http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.167802

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