Science Simplified!

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Comment by Dr. Krishna Kumari Challa on February 9, 2015 at 6:18am

New type of chemical bond discovered : vibrational bond.
This vibrational bond seems to break the law of chemistry that states if you increase the temperature, the rate of reaction will speed up. Back in 1989, a team from the University of British Columbia investigated the reactions of various elements to muonium (Mu) - a strange, hydrogen isotope made up of an antimuon and an electron. They tried chlorine and fluorine with muonium, and as they increased the heat, the reaction time sped up, but when they tried bromine (br), a brownish-red toxic and corrosive liquid, the reaction time sped up as the temperature decreased.

Perhaps, thought one of the team, chemist Donald Flemming, when the bromine and muonium made contact, they formed a transitional structure made up of a lightweight atom flanked by two heavier atoms. And the structure was joined not by van der Waal’s forces - as would usually be expected - but by some kind of temporary ‘vibrational’ bond that had been proposed several years earlier.
"In this scenario, the lightweight muonium atom would move rapidly between two heavy bromine atoms, 'like a Ping Pong ball bouncing between two bowling balls,' Fleming says. The oscillating atom would briefly hold the two bromine atoms together and reduce the overall energy, and therefore speed, of the reaction.”
"Fundamental Change in the Nature of Chemical Bonding by Isotopic Substitution"
http://onlinelibrary.wiley.com/doi/10.1002/anie.201408211/abstract
The research team watched as the light muonium and heavy bromine formed a temporary bond. “The lightest isotopomer, BrMuBr, with Mu the muonium atom, alone exhibits vibrational bonding in accord with its possible observation in a recent experiment on the Mu + Br2 reaction.
Accordingly, BrMuBr is stabilised at the saddle point of the potential energy surface due to a net decrease in vibrational zero point energy that overcompensates the increase in potential energy.”

In other words, the vibration in the bond decreased the total energy of the BrMuBr structure, which means that even when the temperature was increased, there was not enough energy to see an increase in the reaction time.

While the team only witnessed the vibrational bond occurring in a bromine and muonium reaction, they suspect it can also be found in interactions between lightweight and heavy atoms, where van der Waal’s forces are assumed to be at play.

"The work confirms that vibrational bonds - fleeting though they may be - should be added to the list of known chemical bonds

Comment by Dr. Krishna Kumari Challa on February 9, 2015 at 6:01am

Tuna keep their hearts warm in cold depths - how this is done?
It may be a little odd sounding, but tuna are very cold hearted creatures. No, they aren't unnecessarily cruel or stoic in life. Instead, they just can literally have cold hearts, with the organ somehow able to keep functioning even when deep-diving chills it to temperatures that would stop a human heart. Now researcher think they know how the fish is capable of this amazing feat.

Bluefin tuna have increasingly been spotted in East Greenland waters, and scientists are mystified as to what is driving this northward movement.
Bluefin Tuna Mysteriously Move to East Greenland Waters
The Pacific Bluefin tuna, a fish popular among sushi eaters, is verging on the brink of extinction as the global food market places
Sushi Eaters Push Bluefin Tuna Towards Extinction

"Tunas are at a unique place in bony fish evolution" researcher Barbara Block at Stanford University explained in a recent statement. "Their bodies are almost like ours - endothermic (warm blooded/bodied), but their heart is running as all fish at ambient temperatures. How the heart keeps pumping as the fish moves into the colder water is the key to their expanded global range."

As detailed in a new study published in the journal Proceedings of the Royal Society B, Block and her colleagues looked to bluefin tuna to learn more about this fascinating ability. A top predator of the Pacific Ocean, the bluefin are renown for their epic migrations, traveling far in search of prey and diving chillingly deep - up to 1000 meters below the ocean surface.

"When tunas dive down to cold depths their body temperature stays warm but their heart temperature can fall by 15°C within minutes," added Holly Shiels, from the University of Manchester. "The heart is chilled because it receives blood directly from the gills which mirrors water temperature. This clearly imposes stress upon the heart but it keeps beating, despite the temperature change. In most other animals the heart would stop."

Shiels, Block, and Manchester researcher Gina Gali reportedly used electromagnetic tags to monitor bluefins in their lengthy migration from the waters of Japan all the way to the Californian coast. The tags allowed them to measure the depth at which each fish swam on its journey, its internal body temperature at any one point, and the ambient water temperature surrounding it. This data was then reapplied in lab simulations using single tuna heart cells to see how they beat.

The trio found out that rushes of adrenaline during dives helped keep essential calcium circulating in the tunas' hearts, which kept them pumping their chilled blood.

"We were recording the fish swimming down into colder depths only to resurface quickly into the warmer surface waters, a so called 'bounce' dive," said Block. " From work at sea and in the lab we now know the fish hearts slow as they cool and as they resurfaced it sped up. Our findings suggest adrenalin, activated by the stress of diving, plays a key role in maintaining the heart's capacity to supply the body with oxygen."

Now the researchers are wondering if this is a new and unique mechanic among only tuna, or if other species have taken on this adaptation as well.

Comment by Dr. Krishna Kumari Challa on February 8, 2015 at 7:21am

Copper's link to Parkinson’s Disease

Parkinson’s disease (PD) – a neurodegenerative disease that causes loss of motor function – results from interactions between genetic and environmental risk factors that are not fully understood.

Aaron Bowman, Ph.D., and colleagues tested the hypothesis that a genetic predisposition to PD makes neurons more vulnerable to exposure to heavy metals, a known environmental risk factor for PD.

The investigators generated human induced pluripotent stem cells (hiPSCs) from patients with mutations in the PARK2 gene, one of the most common causes of early onset PD, and from controls without mutations or a family history of PD. They found that PARK2 mutant neuroprogenitors – neural cells derived from the hiPSCs – showed increased vulnerability to copper and cadmium cytotoxicity, compared to controls. The cells had a substantial increase in reactive oxygen species and mitochondrial dysfunction after copper exposure.

The findings, reported in the January issue of Neurobiology of Disease
http://www.sciencedirect.com/science/article/pii/S0969996114002952
PARK2 patient neuroprogenitors show increased mitochondrial sensitivity to copper. Asad A. Aboud, Andrew M. Tidball, Kevin K. Kumar, M. Diana Neely, Bingying Han, Kevin C. Ess, Charles C. Hong, Keith M. Erikson, Peter Hedera, Aaron B. Bowman. Neurobiology of Disease. 2015. Volume 73, January 2015, Pages 204–212.

Comment by Dr. Krishna Kumari Challa on February 8, 2015 at 7:13am

Comment by Dr. Krishna Kumari Challa on February 7, 2015 at 9:01am

Recent infections may curb risk of rheumatism
Recent gut and urinary tract infections may curb the risk of developing rheumatoid arthritis, suggests a new study from Karolinska Institutet published online in the journal Annals of the Rheumatic Diseases. According to the researchers, one possible explanation could lie in the way in which these infections alter the types of bacteria resident in the gut (microbiome).

The research team set out to look at the impact of different types of infection on the risk of developing rheumatoid arthritis in almost 6500 people living in south and central Sweden.
All participants were asked whether they had had any gut, urinary tract, or genital infections in the preceding two years. They were also asked if they had had prostatitis (inflamed prostate), or antibiotic treatment for sinusitis, tonsillitis/other throat infection, or pneumonia during this time.

Gut, urinary tract, and genital infections within the preceding two years were each associated with a significantly lowered risk of developing rheumatoid arthritis: 29 percent, 22 percent, and 20 percent, respectively. Further, having all three types of infection in the preceding two years was linked to a 50 percent lower risk, after taking account of influential factors.

By contrast, no such associations were found for recent respiratory infections and pneumonia. Factoring in smoking and socioeconomic background made no difference to the overall findings. However, since this is an observational study researchers point out that no definitive conclusions can be drawn about cause and effect.
Conclusions Gastrointestinal and urogenital infections, but not respiratory infections, are associated with a significantly lowered risk of RA. The results indicate that infections in general do not affect the risk for RA, but that certain infections, hypothetically associated with changes in the gut microbiome, could diminish the risk.
http://ard.bmj.com/content/early/2015/01/16/annrheumdis-2014-206493

Comment by Dr. Krishna Kumari Challa on February 7, 2015 at 8:57am

Psychobiotics: How gut bacteria mess with your mind

WE HAVE all experienced the influence of gut bacteria on our emotions. Just think how you felt the last time you had a stomach bug. Now it is becoming clear that certain gut bacteria can positively influence our mood and behaviour. The way they achieve this is gradually being uncovered, raising the possibility of unlocking new ways to treat neurobehavioural disorders such as depression and obsessive-compulsive disorder (OCD).

We acquire our intestinal microbes immediately after birth, and live in an important symbiotic relationship with them. There are far more bacteria in your gut than cells in your body, and their weight roughly equals that of your brain. These bacteria have a vast array of genes, capable of producing hundreds if not thousands of chemicals, many of which influence your brain.
http://www.newscientist.com/article/mg22129530.400-psychobiotics-ho...|NSNS|2015-0702-AUS-febemi2_apac|evergreen&utm_medium=EMP&utm_source=NSNS&utm_campaign=FebEMi2_APAC&utm_content=evergreen

Comment by Dr. Krishna Kumari Challa on February 7, 2015 at 8:35am

AVIAN INFLUENZA
Are Wild Birds to Blame?
Almost as soon as H5N1 avian influenza began its deadly sweep across Asia, people fingered migratory birds as likely culprits in its spread. Migrating birds offer an obvious way to connect the dots of H5N1 outbreaks along the east coast of Asia and, in just the past few months, its unexpected cross-continent jump to Siberia, Kazakhstan, and Turkey. Moreover, researchers have long known that these birds commonly harbor less virulent flu viruses, and many wild birds mingle with Asia's free-ranging domestic poultry, which have been decimated by H5N1.

But avian experts have been almost universally skeptical that wild birds are spreading the virus. One reason is that sampling of tens of thousands of birds has failed to turn up a single healthy wild bird carrying the pathogenic strain of H5N1, which has caused the death of more than 100 million domestic birds—and at least 60 humans—in Asia. Evidence so far suggests that H5N1 kills wild ducks and geese nearly as efficiently as it does chickens. “Dead ducks don't fly” has been the refrain, as avian experts point out that sick and dying birds simply can't spread viruses very far. Instead, epidemiologists investigating the virus's jump, even to geographically far-flung regions, keep turning up evidence suggesting that the poultry trade and other human activities are responsible.

Now, however, evidence implicating wild birds is starting to convince even some of the doubters. “Until about 2 months ago, I was pretty skeptical on whether wild birds were playing a role,” says David Suarez, a virologist with the U.S. Department of Agriculture's (USDA's) Southeast Poultry Research Laboratory in Athens, Georgia. “But now I feel that there is much stronger evidence that wild birds are spreading the virus.” What changed his mind, he says, was the death of 100 or so ducks, gulls, geese, and swans from H5N1 at a remote lake in Mongolia that he believes can't be explained by human activities. And, he and others add, in an unexpected twist, it's beginning to look as though the culprits might not be the long-suspected migratory waterfowl but another yet-unidentified wild species.

The implications are huge. If wild birds are carrying the disease, says Suarez, “it will be difficult or impossible to control the spread from country to country.” Nailing down the answer became even more urgent last week with the confirmation that H5N1 has now entered Europe.
http://www.sciencemag.org/content/310/5747/426.full?sid=2cf74c06-2d...

Comment by Dr. Krishna Kumari Challa on February 6, 2015 at 7:16am

A study, published in the journal Science recently, used a mathematical model to simulate the changes that take place during desertification and matched the theoretical results with real observations in termite-inhabited regions on the edge of deserts. And it was found that mounds of soil made by termites when they build their high-rise nests have been found to hold back the encroachment of deserts in dry, savannah grasslands threatened with desertification.
The ground surrounding termite mounds store nutrients and water better than it otherwise would, which allows plants to grow and flourish while the empty, termite-free land further away dries out, the researchers said.

A study discovered that the myriad of tiny underground tunnels created by termites when they build their multi-storey nests allow rainwater to penetrate the soil which helps to slow the spread of deserts in the dry grasslands of Africa, South America and Asia.

“The rain is the same everywhere, but because termites allow water to penetrate the soil better, the plants grow on or near the mounds as if there were more rain.
So, termites stop desertification! Termite mounds are a boon to ecology!

Comment by Dr. Krishna Kumari Challa on February 5, 2015 at 9:13am

Unconscious thought not so smart after all

Study on decision-making stokes controversy over power of distracted mind.
If you have to make a complex decision, will you do a better job if you absorb yourself in, say, a crossword puzzle instead of ruminating about your options? The idea that unconscious thought is sometimes more powerful than conscious thought is attractive, and echoes ideas popularized by books such as writer Malcolm Gladwell’s best-selling Blink.

Science pours in from Rosetta comet mission
GM microbes created that can’t escape the lab
Crunch time for pet theory on dark matter

But within the scientific community, ‘unconscious-thought advantage’ (UTA) has been controversial. Now Dutch psychologists have carried out the most rigorous study yet of UTA — and find no evidence for it.

Their conclusion, published this week in Judgement and Decision Making, is based on a large experiment that they designed to provide the best chance of capturing the effect should it exist, along with a sophisticated statistical analysis of previously published data.
http://www.nature.com/news/unconscious-thought-not-so-smart-after-a...

Comment by Dr. Krishna Kumari Challa on February 5, 2015 at 8:04am

Scientists unlock one of Nature’s best-kept secrets: How plants make natural medicines
Scientists at the John Innes Centre have discovered how plants make valuable natural products we rely on today for use as medicines, flavours and scents. This discovery has the potential to pave the way for the creation of entirely new drugs, flavourings and cosmetic ingredients.

Most plant-derived drugs, scents and flavours contain hydrocarbon rings in their structures – and until now exactly how Nature makes them has remained a mystery.

Recent work by a team of scientists at the John Innes Centre, led by Dr Paul O'Maille, resulted in the discovery of the origins of these cyclic or ring forming reactions in plants – which yield medicines like artemisinin: the most potent antimalarial drug, as well as flavours such as ginger and scents like bergamot.

The key to their success was breeding enzymes, the protein machinery that catalyses chemical reactions in plants. In particular they focused on enzymes that catalysed the formation of terpenes: the most diverse class of predominantly cyclic (ring-containing) natural products. By breeding a pair of enzymes, one that makes linear, less complex terpenes with one that makes cyclic terpenes, Dr Melissa Salmon, the lead author on the paper, was able to localize the trait of cyclization in the protein structure.
This research was published recently in Nature Communications.

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