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Comment by Dr. Krishna Kumari Challa on January 20, 2016 at 9:09am

More than 90 percent of the heat trapped by greenhouse gas pollution since the 1970s has wound up in the oceans, and research published Monday revealed that a little more than a third of that seafaring heat has worked its way down to depths greater than 2,300 feet (700 meters).
Plunged to ocean depths by winds and currents, that trapped heat has eluded surface temperature measurements, fueling claims of a “hiatus” or “pause” in global warming from 1998 to 2013. But by expanding cool water, the deep-sea heat’s impacts have been indirectly visible in coastal regions by pushing up sea levels, contributing to worsening high-tide flooding.
The research, published in Nature Climate Change, was led by Lawrence Livermore National Laboratory.

http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate2...

Comment by Dr. Krishna Kumari Challa on January 20, 2016 at 8:14am

Q:How can we receive digital imagery of Pluto so quickly from across the solar system?

Answer: Pluto is about 4.9 billion kilometers away from earth. The digital imagery is transmitted via wireless communication, which is based on electromagnetic radiation which travels with light speed, e.g. about 300.000 kilometers per second in the vacuum of space. Which means signals need about 4 1/2 hours to earth. It takes additional time to actually transmit all the data, but probably not too much. Five hours all in all are enough.

Comment by Dr. Krishna Kumari Challa on January 16, 2016 at 7:21am

How can plants grow in space?

Yes, they have a problem in space...Zero Gravity!

The complication that needs to be overcome is that plants make use of gravity when planted to orient themselves (as they can't rely on being planted the right way up), so that their roots go down and their sprouts go up. Without gravity, they will tend to just stay at around the same depth and not sprout. One astronaut reported that this was simple enough to fix, however, just by plucking the ends out of the soil, pulling them to the surface, when they first sprout. From this point, the plant can orient itself using light and will continue to grow. Roots don't suffer as much, as they just grow away from the seed and avoid light (the surface), so develop relatively normally.

After this, growth is mostly normal. The resulting plants can look a little unusual because they don't have the usual drooping from gravity, so will tend to be more upright.
Crew members aboard the International Space Station have been growing  plants and vegetables for years in their "space garden." A space station study is helping investigators develop procedures and methods that allow astronauts to grow and safely eat space-grown vegetables.

Surprises in microgravity research are not unusual, though, and it turned out that overwatered traditional module sprouted and developed leaves about twice as fast.

The second surprising result was discovered when the root modules were unpacked on the ground. The new fertilizer being tested had a slower and more even release rate, which had helped lower the plants' accumulation of salts during ground studies. Investigators expected to see higher salt accumulation in the space modules, but the opposite occurred.

The current theory is that the extra water and larger plant uptake of fertilizer caused the root modules to remove nutrients faster and release fertilizer faster, thus preventing the salt accumulations that were observed in the slower-growing ground studies.

The space station's ability to provide on-the-spot adjustments to experiment conditions or opportunities to quickly repeat microgravity experiments with new conditions are a big plus for researchers.

Read more here:
Growing Plants and Vegetables in a Space Garden

Comment by Dr. Krishna Kumari Challa on January 16, 2016 at 7:09am

Astronomers have discovered the brightest star explosion ever, a super supernova that easily outshines our entire Milky Way. An international team revealed “the most powerful supernova observed in human history” Thursday in the latest Science journal. The astronomers used a network of telescopes around the world to spot the record-breaking supernova last year.

Comment by Dr. Krishna Kumari Challa on January 15, 2016 at 11:34am

Researchers have confirmed that a toxic chemical in the fruit of the Asian lychee tree (Litchi chinensis) is responsible for outbreaks of a fatal brain sickness in children in India’s Bihar state where the fruit is commercially grown. Methylene cyclopropyl-glycine (MCPG) or hypoglycin G was detected in both semi-ripe and ripe lychee fruit by a team of virologists led by T. Jacob John at the Christian Medical College (CMC), Vellore, in Tamil Nadu. The findings were published in Current Science. The chemical is akin to another toxin methylene cyclopropylalanine (MCPA), which is found in ackee (Blighia sapida), a West Indian fruit. Both lychee and ackee come from the Sapindaceae (soapberry) family of plants. MCPG is known to cause hypoglycaemic encephalopathy, a metabolic illness that affects the brain when body sugar levels are low due to fasting or undernourishment.

Only undernourished children living near lychee orchards appeared to suffer and during May and June, when the fruit is harvested.

MCPG forms compounds with carnitine and coenzyme A and makes them less available for important metabolic reactions in the body. Both carnitine and coenzyme A are essential for fatty acid metabolism. When a person is fasting, stored glycogen is released initially for energy production. Later, body fat is mobilized and this requires breakdown of fatty acids aided by carnitine and coenzyme. When this metabolism is impaired, hypoglycaemia develops.The toxin is seen in high concentrations in the seed and semi-ripe pulp. Children who are malnourished are most vulnerable as they have low glycogen stores  While MCPG was known to be present in lychee seeds, the study established its presence in the flesh of the fruits as well. Immediate treatment for victims includes administration of glucose.

http://www.currentscience.ac.in/Volumes/109/12/2195.pdf

Comment by Dr. Krishna Kumari Challa on January 14, 2016 at 10:12am

A new half-solid, half-liquid material can heal itself ...
A new half-solid, half-liquid adaptive material created by scientists in the US displays a number of amazing properties, including the ability to self-heal – stitching itself back together once divided – and self-stiffen back into its original shape after being compressed.

The material, called SAC – which stands for self-adaptive composite – is composed of a mass of sticky, micron-scale rubber balls that cling together to create a solid matrix. The composite is capable of healing itself repeatedly when cracked, and behaves kind of like a sponge, regaining its original form after being disturbed.

Comment by Dr. Krishna Kumari Challa on January 10, 2016 at 10:47am

Comment by Dr. Krishna Kumari Challa on January 9, 2016 at 7:00am

Graphene shows promise to efficiently filter nuclear waste

Membranes made from graphene can act as a sieve, separating protons from heavier nuclei of hydrogen isotope deuterium
graphene can be used to clean up nuclear waste by filtering different isotopes of hydrogen, a new study has found.

Researchers led by Andre Geim from University of Manchester in UK demonstrated that using membranes made from graphene can act as a sieve, separating protons — nuclei of hydrogen — from heavier nuclei of hydrogen isotope deuterium.

The process could mean producing heavy water for nuclear power plants could be ten times less energy intensive, simpler and cheaper using graphene.

One of the hydrogen isotopes, deuterium, is widely used in analytical and chemical tracing technologies and, also, as heavy water required in thousands of tonnes for operation of nuclear power stations.

The heaviest isotope, tritium, is radioactive and needs to be safely removed as a byproduct of electricity generation at nuclear fission plants. Future nuclear technology is based on fusion of the two heavy isotopes.
The researchers found that deuterons were not only effectively sieved out by their one atom thick membranes, but were sieved with a high separation efficiency. The discovery makes monolayers of graphene and boron nitride attractive as separation membranes to enrich mixtures of deuterium and tritium.

Furthermore, the researchers showed that the separation is fully scalable. Using chemical-vapour-deposited (CVD) graphene, they built centimetre-sized devices to effectively pump out hydrogen from a mixture of deuterium and hydrogen.
The study was published in the journal Science.

Comment by Dr. Krishna Kumari Challa on January 5, 2016 at 7:26am

The periodic table has been given four new elements, changing one of science’s most fundamental pieces of knowledge.

Elements 113, 115, 117 and 118 will now be added to the table’s seventh row and make it complete, after they were verified by the International Union of Pure and Applied Chemistry on 30 December,2015. But they are yet to receive their final names or symbols.

The new elements were discovered by team from Japan, Russia and the USA, who will all get to name their own new elements.
Read more

All of the four new admissions are man-made. The super-heavy elements are created by shoving lighter nuclei into each other and are found in the radioactive decay — which only exists for a tiny fraction of a second before they decay into other elements.

Comment by Dr. Krishna Kumari Challa on January 4, 2016 at 7:21am

Reason for frothing lake...
Phosphates in detergents is what causes frothing Bellandur lake in Bangalore.
Based on a report by researchers from Indian Institute of Science (IISc.), Union Environment Minister Prakash Javadekar said on Thursday he would consider restrictions on detergents which were considered the primary reason for the froth that has engulfed the nearly 700-acre lake.

“I will take it up with the department concerned, to check if an alternative that is environmentally friendly and cost-effective to phosphates can be used. If we can ban diclofenac (a painkiller for cattle which was found to be the reason for the mass deaths of endangered vultures), then we can surely consult and think of a better alternative,” he said at a seminar on climate change here.

The Minister was briefed about the problems of Bellandur lake, where froth started to rise alarmingly in April 2015, and within a month, a portion of froth was even seen catching fire.

A recent report by researcher T.V. Ramachandra on the pollution in the lake, submitted to the Minister, conclusively shows that the froth appeared because of higher concentration of phosphates in the lake.

Phosphates form a major component in household detergents, and make their way to the lake through the estimated 500 million litres of sewage that flows into Bellandur and Vathur lakes. Phosphates do not disintegrate, and continue to remain in the water, which ends up being used for agriculture further downstream of the lake.

The researcher had previously said that more than 70 per cent reduction in phosphates was needed to reduce eutrophication (excessive nutrients in the lake that cause dense growth of plants, including water hyacinth) in the lake. This sort of reduction has been seen in lakes of developed countries where stringent measures on phosphates were imposed to preserve waterbodies.

On May 16, 2015, Pockets of froth on the lake caught fire, which is believed to have been caused by built-up methane in the bubbles.

High phosphate regions are when the limit reaches 4.22 to 5.76 parts per million (for drinking water, less than 0.1 ppm prescribed by the WHO)

Enhanced biological oxygen demand is when 119 to 140 parts per million (should be 30 ppm or less)

Decreased dissolved oxygen is 0 to 1.06 parts per million

Excessive phosphate encourages wild growth of algae and aquatic plants which sucks up oxygen from the lake and chokes inlets. This in turn adversely affects flora and fauna of the lake.

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