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Comment by Dr. Krishna Kumari Challa on November 14, 2015 at 9:28am

The human brain facts:
The human brain has 86 billion neurons in all: 69 billion in the cerebellum, a dense lump at the back of the brain that helps orchestrate basic bodily functions and movement; 16 billion in the cerebral cortex, the brain’s thick corona and the seat of our most sophisticated mental talents, such as self-awareness, language, problem solving and abstract thought; and 1 billion in the brain stem and its extensions into the core of the brain.
The human brain is also unique in its unsurpassed gluttony. Although it makes up only 2 percent of body weight, the human brain consumes a whopping 20 percent of the body’s total energy at rest.

Human brain evolution likely required a metabolic trade-off. In order for the brain to grow, other organs, namely the gut, had to shrink, and energy that would typically have gone to the latter was redirected to the former. For evidence, they pointed to data showing that primates with larger brains have smaller intestines. The invention of cooking was crucial to human brain evolution. Soft, cooked foods are much easier to digest than tough raw ones, yielding more calories for less gastrointestinal work. Perhaps, then, learning to cook permitted a bloating of the human brain at the expense of the gut. Other researchers have proposed that similar trade-offs might have occurred between brain and muscle, given how much stronger chimps are than humans.

Again and again, researchers have cited the evolutionary surge in human brain size as the key reason for our exceptionally high degree of intelligence compared to other animals. Yes, a large brain packed with neurons is essential to what we consider high intelligence.

Comment by Dr. Krishna Kumari Challa on November 13, 2015 at 9:28am

Truth here and now...1

Q: What Really Causes Autism?

A: Not vaccines! No. A range of mutations—common, rare, inherited and spontaneous—in more than 70 different genes are now linked to the disorder.

Here are the latest findings and ideas from scientists about what might really cause this mysterious condition.

Genetics

There is strong evidence that changes in our genes contribute to autism.

For one thing, the disorder is highly heritable. Families that have one child with autism have a 1 in 20 chance of having a second child with autism.

Research has also shown that the genetic changes that contribute to autism don't have to be inherited — they may also arise spontaneously.

In total, scientists have identified about 20 genes that may be involved in autism. Children with a genetic mutation on chromosome 17 were 14 times more likely to develop autism than those without the mutation.

Pesticides

Exposure to pesticides has also been linked to autism. Some studies have found that pesticides may interfere with genes involved in the central nervous system. Scientists think that chemicals in pesticides may adversely affect those who are genetically predisposed to autism.

Pharmaceuticals

Babies that have been exposed to certain pharmaceuticals in the womb, including valproic acid and thalidomide, have been found to have a higher risk of autism.

Thalidomide is a drug that was first used in the 1950s to treat morning sickness, anxiety and insomnia. The drug was withdrawn from the market after it was linked with birth defects, but is currently prescribed for a severe skin disorder and as a treatment for cancer. Valproic acid is a medication prescribed for seizures, mood disorders and bipolar disorder. 

Parental age

As parents grow older, they have a higher risk of having children with autism, according to some studies. A study published last February found that women who are 40 years old have a 50 percent greater risk of having a child with autism than women who are between 20 and 29 years old.

Researchers aren't sure why parental age may influence autism risk, but it might be related to genetic mutations that occur in the sperm or the egg as parents grow older.

The development of the brain

Particular areas of the brain, including the cerebral cortex and the cerebellum, have been implicated in autism. These brain areas are thought to be responsible for concentration, movement and mood regulation.

Irregularities in the levels of neurotransmitters, such as dopamine and serotonin, have also been tied to autism. Problems regulating dopamine can lead to problems with concentration and movement disabilities, while troubles controlling serotonin levels can result in mood problems.

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

Turning the tide ... using the worst thing happened to your work to do your best... How scientists use out of control satellites to test a theory...

Two satellites that were accidentally launched into the wrong orbit will be repurposed to make the most stringent test to date of a prediction made by Albert Einstein’s general theory of relativity—that clocks run more slowly the closer they are to heavy objects.

The satellites, operated by the European Space Agency (ESA), were mislaunched last year by a Russian Soyuz rocket that put them into elliptical, rather than circular, orbits. This left them unfit for their intended use as part of a European global-navigation system called Galileo.

But the two crafts still have atomic clocks on board. According to general relativity, the clocks' 'ticking' should slow down as the satellites move closer to Earth in their wonky orbits, because the heavy planet’s gravity bends the fabric of space-time. The clocks should then speed up as the crafts recede.

On November 9, ESA announced that teams at Germany's Center of Applied Space Technology and Microgravity (ZARM) in Bremen and the department of Time–Space Reference Systems at the Paris Observatory will now track this rise and fall. By comparing the speed of the clocks’ ticking with the crafts’ known altitudes—pinpointed within a few centimetres by monitoring stations on the ground, which bounce lasers off the satellites—the teams can test the accuracy of Einstein's theory.

http://www.nature.com/news/wayward-satellites-repurposed-to-test-ge...

Comment by Dr. Krishna Kumari Challa on November 13, 2015 at 9:05am

Comment by Dr. Krishna Kumari Challa on November 12, 2015 at 11:58am

Scientists breach brain barrier to treat sick patient
For the first time, doctors have breached the human brain's protective layer to deliver cancer-fighting drugs.

The Canadian team used tiny gas-filled bubbles, injected into the bloodstream of a patient, to punch temporary holes in the blood-brain barrier.

A beam of focused ultrasound waves applied to the skull made the bubbles vibrate and push their way through, along with chemotherapy drugs.

Six to 10 more patients will undergo the same procedure as part of a trial.

Experts said the experimental technique used at Sunnybrook Health Sciences Centre was exciting because it meant doctors might be able to give cancer patients potent drugs that otherwise would not work.
The same non-invasive method could also be used for other brain diseases, such as dementia and Parkinson's.
Blood-brain barrier

The blood-brain barrier keeps pathogens and toxins away from the central nervous system. But this tightly packed layer of cells, which separates the brain from its blood vessels, can be a hindrance if you want to deliver drugs into the brain.

The Sunnybrook team temporarily ripped holes in the barrier to allow chemotherapy a safe passage through.
The patient was given an intravenous infusion of chemotherapy followed by a small dose of the micro-bubbles that would punch a way through once they reached the target area of the brain and the ultrasound beam was switched on.

Brain scans suggest the treatment went to plan, and the researchers will soon examine a small part Ms Hall's tumour (removed surgically the day after the therapy) to confirm how much of the chemotherapy penetrated.
"Opening the blood-brain barrier using focused ultrasound beams has been a goal of researchers for about a decade, with the Toronto group being at its forefront, and it is exciting to see this reaching the clinic at last.

"The use of ultrasound for enhancing the local delivery of drugs to a number of different targets in the body is being investigated by a number of centres around the world, including the UK, and shows particular promise in the field of cancer chemotherapy."

Comment by Dr. Krishna Kumari Challa on November 12, 2015 at 11:33am

Brain Too Can Get Fossilised

Scientists have long maintained that brains do not fossilise but new research has provided the strongest evidence yet that it is possible. In fact, the brains of a set of 520-million-year-old arthropods did just that.

The species, Fuxianhuia protensa, is an extinct arthropod that roamed the seafloor about 520 million years ago. It would have looked something like a very simple shrimp.

“Each of the fossils found at Chengjiang Shales fossil-rich sites in southwest China revealed F protensa’s ancient brain looked a lot like a modern crustacean’s,” said Nicholas Strausfeld, a Regents’ professor in the department of neuroscience at the University of Arizona.

He and his team found that the brains were preserved as flattened carbon films.

This led the research team to a convincing explanation as to how and why neural tissue fossilises.

The only way for an object to be fossilised is for it to be rapidly buried.

Hungry scavengers cannot eat a carcass if the brain is buried faster and as long as the water lacks in oxygen so a buried creature’s tissues escapes being consumed by bacteria as well.

Strausfeld and his collaborators suspect F. protensa was buried by rapid, underwater mudslides a scenario they experimentally recreated by burying sandworms and cockroaches in mud.

According to Strausfeld, the brain withstood the pressure from being rapidly buried under thick mud because the nervous system must have been remarkably dense.

In fact, tissues of nervous systems, including brains, are densest in living arthropods.

In the paper, Strausfeld and Xiaoya Ma from China’s Yunnan University and Gregory Edgecombe from the Natural History Museum in London analysed seven newly discovered fossils of the same species to find, in each, traces of what was undoubtedly a brain.

Strausfeld is now working to elucidate the origin and evolution of brains over half a billion years in the past.

“People, especially scientists, make assumptions. The fun thing about science, actually, is to demolish them,” Strausfeld noted in the paper published in the journal Current Biology.

Comment by Dr. Krishna Kumari Challa on November 12, 2015 at 11:28am

A new confinement state for plasma was discovered

The National Institutes of Natural Sciences National Institute for Fusion Science applied the "Momentary Heating Propagation Method" to the DIII-D tokamak device operated for the United States Office of Science, Department of Energy, by the General Atomics and made the important discovery of a new plasma confinement state. This discovery was introduced in the November 4, 2015, issue of Scientific Reports, a journal of the British science journal Nature group, in an article titled "Self-regulated oscillation of transport and topology of magnetic islands in toroidal plasmas." Seeking to achieve fusion energy, research on high-temperature and high-density plasma confinement by magnetic fields is being conducted around the world. In a magnetically confined plasma, as the core temperature of the plasma increases, the flow of disturbed plasma called turbulence emerges. Turbulence does not stop at the place of its generation, and moves circumferentially like a surge of waves.

In magnetically confined plasmas twofold confinement areas called magnetic islands exist. In these areas there is no temperature gradient that results in the source of turbulence. For that reason turbulence generated outside the magnetic island where a temperature gradient exists enters into the magnetic island, and the confinement state inside the magnetic island will be determined depending upon the intensity of turbulence. In future fusion plasma, too, it will be extremely important to improve the magnetic island's confinement state. Further, even in solar plasmas, it has been indicated from solar flare emissions that magnetic islands may exist. Thus, research on turbulence in magnetic islands is an extremely important topic.

Professor Katsumi Ida, Assistant professor Tatsuya Kobayashi, and the LHD experiment group, together with Professor Shigeru Inagaki at Kyushu University, have, together with Dr. T. Evans, a DIII-D senior researcher, discovered for the first time in the world a new confinement state inside a magnetic island by applying the "momentary heating propagation method" to the DIII-D plasma. The "momentary heating propagation method" allows the plasma confinement performance (adiabaticity) to be diagnosed from the amplitude of temperature variations and the propagation speed caused by the momentary heating.

This discovery, because it is essential for improving the confinement of the fusion reactor plasma, will be an important compass pointing in the direction of future fusion research.

These research results were published in the British academic science journal Scientific Reports (online edition) of the Nature group on November 4, 2015, and is widely available.

Comment by Dr. Krishna Kumari Challa on November 6, 2015 at 8:20am

A parasite's cancerous cells can give human beings cancer! Yes, true. This really has happened!
In a rare case, a patient’s weakened immune system may have let tapeworm spread disease
A 41-year-old man in Medellín, Columbia, went to the doctor complaining of fever, cough, fatigue and weight loss that had lasted several months. He had been already infected with AIDS and had a very weak immune system by then. Scans revealed tumors in his lungs, liver, adrenal glands, lymph nodes and other spots in his body. The disease looked like cancer, but it puzzled doctors: the small cells in the growths weren’t human cancer cells. They were much smaller!

DNA analysis revealed a shock: The cancer cells came from dwarf tapeworms (Hymenolepiasis nana), pathologist Atis Muehlenbachs of the U.S. Centers for Disease Control and Prevention and colleagues report in the Nov. 5 New England Journal of Medicine. Contagious cancers affect dogs, Tasmanian devils and clams, but this is the first time researchers have found a parasite living in him giving a person cancer.

HIV infection had weakened the man’s immune system so that tapeworm stem cells could grow unchecked, the researchers speculate. Mutations then turned the stem cells into cancer. The case raises concerns that people with weakened immune systems may be in danger of contracting similar tapeworm cancers. “This is a rare disease,” Muehlenbachs says, but “we don’t know how rare.”

Comment by Dr. Krishna Kumari Challa on November 6, 2015 at 7:27am

Scientists tinker with evolution to save Hawaii coral reefs
Hawaii researchers accelerate evolution in attempt to save Hawaii's coral reefs
Scientists at a research center on Hawaii's Coconut Island have embarked on an experiment to grow "super coral" that they hope can withstand the hotter and more acidic oceans that are expected with global warming.
When coral is stressed by changing environmental conditions, it expels the symbiotic algae that live within it and the animal turns white or bright yellow, a process called bleaching.
If the organisms are unable to recover from these bleaching events, especially when they recur over several consecutive years, the coral will die.
The researchers are taking the coral to their center on the 29-acre isle, once a retreat for the rich and famous and home to television's Gilligan's Island, and slowly exposing them to slightly more stressful water.

They bathe chunks of coral that they've already identified as having strong genes in water that mimics the warmer and more acidic oceans. They are also taking resilient strains and breeding them with one another, helping perpetuate those stronger traits. They have given them experiences that we think are going to raise their ability to survive stress.

The theory they are testing is called assisted evolution, and while it has been used for thousands of years on other plants and animals, the concept has not been applied to coral living in the wild.
-AP

Comment by Dr. Krishna Kumari Challa on November 6, 2015 at 7:20am

183 scientists sign letter asking BMJ to retract its bogus nutrition investigation

The investigation has 'no place in the pages of a prominent scientific journal'
More than 180 scientists from around the world have signed a letter urging the British Medical Journal to retract its bogus investigation of the 2015 US dietary guidelines report. As The Verge previously reported, the investigation contains multiple misleading statements and factual inaccuracies. But today's letter, which was sent to the BMJ this morning, doesn't mince words. It outlines the many problems with the article, and states that the investigation is "so riddled with errors" that it has "no place in the pages of a prominent scientific journal."
The US government publishes a revised set of dietary guidelines every five years. These guidelines are very important; they affect how companies label food, what scientists focus on in their research, and what students eat in school. But in September, the BMJ published an investigation that went after the report that informs those guidelines; it was written by Nina Teicholz, author of a book entitled The Big Fat Surprise: Why Butter, Meat and Cheese Belong in a Healthy Diet. The article suggested that the committee responsible for the report "abandoned established methods for most of its analyses," overlooking a number of important studies in the process. The article also stated that the committee had "deleted meat" from its list of recommended foods. However, both these statements are untrue.

Unless the BMJ retracts the investigation, many of these errors will likely still be used by the meat industry to suppress the committee's advice on lowering the consumption of red meat.
A number of scientists have told me that it's mind-boggling that the BMJ would publish this article critiquing a report by a panel by well-respected scientists without even asking the panel to respond," says Bonnie Liebman, the director of nutrition at the Center for Science in the Public Interest and the person spearheading the effort to get the journal to retract the investigation. It took the BMJ two days to publish a response from the panel.
In September, a number of news outlets — including Time, Newsweek, and Mother Jones — reported the story without questioning the investigation's faulty reporting. The fact that both the BMJ and Teicholz said that they stood by the article surely did not help.
http://cspinet.org/bmj-retraction-letter.html
http://www.theverge.com/science/2015/11/5/9675598/bmj-183-scientist...

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