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Comment by Dr. Krishna Kumari Challa on December 7, 2015 at 5:31am

How scientists are trying to protect coral reefs

Comment by Dr. Krishna Kumari Challa on December 4, 2015 at 7:36am

Event Horizon Telescope Reveals Magnetic Fields at Milky Way's Central Black Hole

The supermassive black holes at the centers of galaxies are more like cosmic engines, converting energy from infalling matter into intense radiation that can outshine the combined light from all surrounding stars. If the black hole is spinning, it can generate strong jets that blast across thousands of light-years and shape entire galaxies. These black hole engines are thought to be powered by magnetic fields. For the first time, astronomers have detected magnetic fields just outside the event horizon of the black hole at the center of our Milky Way galaxy.
A new study results appear in the Dec. 4th issue of the journal Science.
These magnetic fields have been predicted to exist, but no one has seen them before.
This feat was achieved using the Event Horizon Telescope (EHT) – a global network of radio telescopes that link together to function as one giant telescope the size of Earth. Since larger telescopes can provide greater detail, the EHT ultimately will resolve features as small as 15 micro-arcseconds. (An arcsecond is 1/3600 of a degree, and 15 micro-arcseconds is the angular equivalent of seeing a golf ball on the moon.)
The Event Horizon Telescope made observations at a wavelength of 1.3 mm. The team measured how that light is linearly polarized. On Earth, sunlight becomes linearly polarized by reflections, which is why sunglasses are polarized to block light and reduce glare. In the case of Sgr A*, polarized light is emitted by electrons spiraling around magnetic field lines. As a result, this light directly traces the structure of the magnetic field.

Sgr A* is surrounded by an accretion disk of material orbiting the black hole. The team found that magnetic fields in some regions near the black hole are disorderly, with jumbled loops and whorls resembling intertwined spaghetti. In contrast, other regions showed a much more organized pattern, possibly in the region where jets would be generated.

They also found that the magnetic fields fluctuated on short time scales of only 15 minutes or so.

“Once again, the galactic center is proving to be a more dynamic place than we might have guessed. Those magnetic fields are dancing all over the place.”

https://www.cfa.harvard.edu/news/2015-28

Comment by Dr. Krishna Kumari Challa on December 4, 2015 at 6:03am

Quantum entanglement of multiple particles! Heard it before?
A first-of-its-kind measurement has quantified a mysterious quantum bond shared by several particles rather than just two. The experiment, reported in the Dec. 3 Nature, brings physicists closer to understanding the true scope of this link, known as quantum entanglement.

Entanglement interweaves particles’ fates so that some of each particle’s properties, which are inherently uncertain according to quantum mechanics, are tied to those of its partners. Each particle essentially sacrifices its individuality to become part of an umbrella entangled state. While physicists have developed reliable methods for detecting entanglement between pairs of particles, the measurements get tricky when three or more particles are involved.

A team of quantum physicists from Harvard University measured a property called entanglement entropy, which quantifies the apparent randomness that comes with observing just a portion of an entangled whole. Markus Greiner and colleagues used lasers to create an optical cage with four compartments, each of which held a rubidium atom chilled to nearly absolute zero. The researchers could tweak the laser settings to adjust the height of the walls between compartments. If the walls were low enough, atoms could exploit their strange quantum ability to occupy multiple compartments at once. As the four atoms jumped around, they interacted and established a state of entanglement.

Greiner’s team created a pair of four-compartment systems and confirmed that they were identical using a technique developed for comparing photons. Then the researchers compared portions of the two cages — say, two of the four compartments where atoms could reside. The partial system of one cage differed from the corresponding partial system of the other cage. A difference between parts when the wholes are indistinguishable “only happens if there is entanglement within each system,” Greiner says.

While studying entangled particle pairs is interesting, the real world is dominated by entangled states that encompass much larger sets of particles. Analyzing particles in collections similar to those in Greiner’s experiment could help physicists understand the complex entanglement-rich interactions between electrons in superconductors, which conduct electrical current with no resistance.

http://www.nature.com/nature/journal/v528/n7580/full/nature15750.html

Comment by Dr. Krishna Kumari Challa on December 4, 2015 at 5:57am

Zika virus, which first appeared in Brazil in May, causes fever, rash, vomiting, red eyes and, in some cases, death. Brazilian health officials believe that a Zika infection during pregnancy harms growing fetuses. Pregnant women hit by the virus may be more likely to give birth to babies with the rare birth defect microcephaly, a congenital condition marked by a small head and abnormal brain development.

Over recent months, Brazilian health officials have noted an unusually high number of babies born with microcephaly. From 2010 to 2014, on average, 156 Brazilian babies were born with the birth defect each year. This year, health officials have already recorded 1,248 suspected cases of microcephaly. On November 28, government health officials reported that Zika virus had been found in tissue from a baby born with microcephaly, a find that links the birth defect to the virus.

Zika virus also has been documented in Africa, Southeast Asia and islands in the Pacific including the Cook Islands, French Polynesia and the Federated States of Micronesia. Because the Aedes mosquitoes that carry the virus live around the world, the virus will probably spread to previously unaffected areas.

https://flutrackers.com/forum/forum/emerging-diseases-other-health-...

Comment by Dr. Krishna Kumari Challa on December 3, 2015 at 6:04am

Comment by Dr. Krishna Kumari Challa on December 2, 2015 at 9:26am

Mysteries solved with the help of science and experts in the field...

Comment by Dr. Krishna Kumari Challa on December 2, 2015 at 8:33am

Non-Human Primates Harbor Diverse Mammalian and Avian Astroviruses Including Those Associated with Human Infections.
A new study of nearly 900 nonhuman primates in Bangladesh and Cambodia shows that macaques harbor diverse astroviruses, which can cause infectious gastroenteritis or diarrhea in humans. The research is the first to show evidence of human astroviruses in animals, and among the earliest to demonstrate that astroviruses can move between mammalian species, according to the report, published in PLOS Pathogens. “If you are a bat, you have bat astrovirus, but if you are a monkey, you could have everything,” said Dr. Lisa Jones-Engel, a research scientist at the University of Washington National Primate Research Primate Center and a co-author of the study. Astroviruses from a number of species, including human, bovine, bird, cow and dog, were detected in monkeys, “challenging the paradigm that AstV (astrovirus) infection is species-specific,” the authors wrote. It is still unknown whether these viruses are two-way and can be transmitted to humans. They did find evidence that, in monkeys, two species of astrovirus recombined.
Astroviruses are most commonly associated with diarrhea. They can also cause clinical diseases such as nephritis, hepatitis and encephalitis. However, astroviruses also can be asymptomatic, depending on the species. Currently, the only treatment is oral rehydration.
The researchers said more study is needed to determine if astrovirus infections in nonhuman primates are associated with clinical disease, or whether such infections are asymptomatic. They said none of monkeys sampled in the study appeared to have clinical disease (e.g., diarrhea) at the time of sampling.
http://journals.plos.org/plospathogens/article?id=10.1371/journal.p...

Comment by Dr. Krishna Kumari Challa on December 2, 2015 at 8:25am

Comment by Dr. Krishna Kumari Challa on December 2, 2015 at 8:20am

Comment by Dr. Krishna Kumari Challa on November 30, 2015 at 8:00am

Rain forests create their own rain clouds, replete with microscopic spores, pollen and fungi, or “smells”. How?
On a typical sunny day in the Amazon, 20 billion metric tons of water flow upward through the trees and pour into the air, an invisible river that flows through the sky across a continent.
“This river of vapor that comes up from the forest and goes into the atmosphere is greater than the Amazon River.
Every tree is a silent geyser. Through a process called transpiration, a large tree in the Amazon can release 1,000 liters of water into the atmosphere in a single day. There is a frantic evaporation taking place there.
trees only need to bask in the sunlight to release their invisible steam. Plus, they have the sheer force of numbers; hundreds of billions of trees in the jungle release as many as 20 billion metric tons of water into the atmosphere every day. That means that while the Amazon, which pours 17 billion tons of water into the Atlantic Ocean a day, may be the largest river on earth — it’s still exceeded by the airborne river drifting above the canopy of the trees.
The airborne river turns into rain, which replenishes the forest.
These smells are critical for the lifecycle of the jungle, as the steam from the trees condenses around these microscopic particles, forming clouds, which eventually release torrential rain. This process is unique to the jungle; oceans, for instance, rarely create heavy clouds like the Amazon’s, because sea air is not so richly seeded with plant life. “This relation between a living thing, which is the forest, and a nonliving thing, which is the atmosphere, is ingenious in the Amazon.
Without the Amazon, much of South America would likely have been a desert.

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