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Comment by Dr. Krishna Kumari Challa on November 2, 2014 at 6:36am

Comment by Dr. Krishna Kumari Challa on November 1, 2014 at 8:31am

http://www.washingtonpost.com/world/europe/5-questions-about-the-hi...

Why Scientists Make Promises They Can't Keep
http://www.psmag.com/navigation/politics-and-law/scientists-make-pr...

Comment by Dr. Krishna Kumari Challa on October 31, 2014 at 8:17am

Aircraft that are propelled by beams of light and not fuel...

A new method for improving the thrust-generated by laser-propulsion systems may bring people one step closer to practical use, scientists say. The method, developed by physicists Yuri Rezunkov of the Institute of Optoelectronic Instrument Engineering, Russia and Alexander Schmidt of the Ioffe Physical Technical Institute in Saint Petersburg, Russia has been described in The Optical Society's (OSA) journal Applied Optics.
Currently, the maximum speed of a spacecraft is limited by the amount of fuel that it can carry. Achieving higher speeds means that more fuel must be burned — fuel that has to be carried by the craft, researchers said. These burdensome loads can be reduced, however, if a laser — located at a remote location and not on the spacecraft — were used to provide additional propulsive force. A number of systems have been proposed that can produce such laser propulsion. One of the most promising systems involves a process called laser ablation, in which a pulsed laser beam strikes a surface, heats it up, and burns off material to create a plasma plume — a column of charged particles that flow off the surface.

The outflowing of plasma plume generates additional thrust to propel the craft.

Rezunkov and Schmidt describe a new system that integrates a laser-ablation propulsion system with the gas blasting nozzles of a spacecraft.

Combining the two systems, researchers found, can increase the speed of the gas flow out of the system to supersonic speeds while reducing the amount of burned fuel.

The researchers show that the effectiveness of current laser-propulsion techniques is limited by instability of supersonic gases as they flow through the gas nozzle, as well as production of shock waves that "choke" the nozzle. But those effects can be reduced with the help of a laser-ablation plasma plume. Coupling ablation jet with supersonic gas flow through the nozzle, they found, significantly improves the overall thrust. "These techniques can be used not only for launching small satellites but also for additional acceleration of supersonic aircrafts to achieve Mach 10 and more," Rezunkov said.

Comment by Dr. Krishna Kumari Challa on October 31, 2014 at 7:14am

Mental Leaps Cued by Memory’s Ripples

The same mental processes that organize memories may also coordinate how we make decisions.
http://www.quantamagazine.org/20141022-mental-leaps-cued-by-memorys...

Comment by Dr. Krishna Kumari Challa on October 30, 2014 at 9:09am

Using a naturally occurring protein, scientists have designed a drug nanocarrier that can deliver high doses of cancer drugs to tumors.
Harnessing Nature’s Design To Reduce Chemo Side-Effects
Using a naturally-occurring protein, researchers have designed a nanocarrier that can deliver a high concentration of drugs specifically to tumors. These results, published in the Proceedings of the National Academy of Sciences, could help reduce the side effect of chemotherapy drugs.

In recent years, nanotechnology has been applied to develop drug nanocarriers that can precisely target and kill tumor cells, reducing damages to normal tissue. An ideal nanocarrier for drug delivery should be able to carry high doses of therapeutic drugs, target at tumor cells specifically and have favorable physicochemical properties and biocompatibility.

However, integrating all these characteristics into a single carrier has been complicated. So far, no targeted nanoparticle system has been approved by the US Food and Drug Administration, reflecting in part the complexity of designing particles that meet all of the criteria required for accurate drug delivery.

Professor Yan Xiyun and her colleagues at the Institute of Biophysics, Chinese Academy of Sciences have recently discovered a nanocarrier ideal for efficient anti-tumor drug delivery. They used a naturally-occurring protein, H-ferritin, to form a nanocage that does not require any surface functionalization or property modulation. The new nanocarrier specifically delivers high doses of the therapeutic drug doxorubicin to tumor cells and completely inhibits tumor growth with only a single dose treatment, while exhibiting excellent safety profiles and biocompatibility.

The idea of employing naturally existed materials for targeted drug delivery, instead of focusing on complex particle engineering is a shift in the design concept of drug carriers. The authors hope that it will lead to new directions and methodologies in developing new safe and biocompatible nanomaterials in vivo.
http://www.pnas.org/content/111/41/14900

Comment by Dr. Krishna Kumari Challa on October 30, 2014 at 8:41am

Bio-mimicry!

Cephalopods, which include octopuses, squid, and cuttlefish, are among nature’s most skillful camouflage artists, able to change both the color and texture of their skin within seconds to blend into their surroundings — a capability that engineers have long struggled to duplicate in synthetic materials. (Learn more: http://mitsha.re/1o3Ensl)

Now, a team of researchers has come closer than ever to achieving that goal, creating a flexible material that can change its color or fluorescence and its texture at the same time, on demand, under remote control.

Comment by Dr. Krishna Kumari Challa on October 29, 2014 at 9:52am

And more good news:

ISRO chairman K. Radhakrishnan on 20th Oct., 2014, backed Chief Minister Oommen Chandy’s proposal to use the euphoria created by the Mars Orbiter Mission (MOM) to ignite young minds and encourage students to take to science.

The Government of Kerala will team up with the Indian Space Research Organisation (ISRO) to promote science education and research among students. ISRO chairman K. Radhakrishnan on Monday backed Chief Minister Oommen Chandy’s proposal to use the euphoria created by the Mars Orbiter Mission (MOM) to ignite young minds and encourage students to take to science.

Comment by Dr. Krishna Kumari Challa on October 29, 2014 at 9:10am

The science of human decomposition:
http://www.vox.com/2014/10/28/7078151/body-farm-texas-freeman-ranch...

Comment by Dr. Krishna Kumari Challa on October 29, 2014 at 9:05am

Some good news: relieved to hear this. As long as religion doesn't clash with science and hinder its progress, scientists will have open minds about considering co-existing with religion.

Pope Francis declares evolution and Big Bang theory are right and God isn't 'a magician with a magic wand'

The theories of evolution and the Big Bang are real and God is not “a magician with a magic wand”, Pope Francis has declared.

http://www.independent.co.uk/news/world/europe/pope-francis-declare...

Speaking at the Pontifical Academy of Sciences, the Pope made comments which experts said put an end to the “pseudo theories” of creationism and intelligent design that some argue were encouraged by his predecessor, Benedict XVI.

Francis explained that both scientific theories were not incompatible with the existence of a creator – arguing instead that they “require it”.

“When we read about Creation in Genesis, we run the risk of imagining God was a magician, with a magic wand able to do everything. But that is not so,” Francis said.

He added: “He created human beings and let them develop according to the internal laws that he gave to each one so they would reach their fulfilment.

Comment by Dr. Krishna Kumari Challa on October 28, 2014 at 9:47am

Ecologist Mark Browne knew he’d found something big when, after months of tediously examining sediment along shorelines around the world, he noticed something no one had predicted: fibers. Everywhere. They were tiny and synthetic and he was finding them in the greatest concentration near sewage outflows. In other words, they were coming from us.

In fact, 85% of the human-made material found on the shoreline were microfibers, and matched the types of material, such as nylon and acrylic, used in clothing.

It is not news that microplastic – which the National Oceanic and Atmospheric Administration defines as plastic fragments 5mm or smaller – is ubiquitous in all five major ocean gyres. And numerous studies have shown that small organisms readily ingest microplastics, introducing toxic pollutants to the food chain.

But Browne’s 2011 paper announcing his findings marked a milestone, according to Abigail Barrows, an independent marine research scientist based in Stonington, Maine, who has helped to check for plastic in more than 150 one-liter water samples collected around the world. “He’s fantastic – very well respected” among marine science researchers, says Barrows. “He is a pioneer in microplastics research.”
http://pubs.acs.org/doi/abs/10.1021/es201811s

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