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Comment by Dr. Krishna Kumari Challa on November 8, 2013 at 7:04am

http://www.scientificamerican.com/article.cfm?id=new-limb-regenerat...
New Limb Regeneration Insight Surprises Scientists

Reactivating a dormant gene enhances mice’s healing abilities

Comment by Dr. Krishna Kumari Challa on November 6, 2013 at 8:09am

Comment by Dr. Krishna Kumari Challa on November 6, 2013 at 6:53am

Comment by Dr. Krishna Kumari Challa on November 6, 2013 at 6:39am

Comment by Dr. Krishna Kumari Challa on November 6, 2013 at 6:12am

Confident Multitaskers Are the Most Dangerous behind the Wheel

The dangerous psychology of texting while driving
http://www.scientificamerican.com/article.cfm?id=confident-multi-ta...

Comment by Dr. Krishna Kumari Challa on November 5, 2013 at 7:07am

http://www.scientificamerican.com/article.cfm?id=what-is-4-d-printi...
What Is 4-D Printing?

An M.I.T. lab is tweaking the idea of 3-D printing with the help of smart materials that continue to change even after they leave the printer
The biggest breakthroughs in how we make things lie not in the technology to manipulate materials but in the materials themselves. Such is the thinking behind “4-D printing,” an experimental approach to manufacturing that expands on much-hyped 3-D printing processes. Instead of building static three-dimensional items from layers of plastics or metals, 4-D printing employs dynamic materials that continue to evolve in response to their environment.

This new wrinkle in the maker movement comes courtesy of the Massachusetts Institute of Technology’s Self-Assembly Lab, where director Skylar Tibbits and his team are experimenting with so-called “programmable materials.” The researchers print these substances using a 3-D printer and then watch as the fourth dimension—time—takes over and the materials change shape or automatically reassemble in new patterns.

Improvements in software, computers and assembly processes have enabled more complex designs and greater automation when translating designs into actual things.

Comment by Dr. Krishna Kumari Challa on November 4, 2013 at 6:38am

http://esciencenews.com/articles/2013/11/02/global.warming.led.dwar...

Global warming led to dwarfism in mammals -- twice

Mammal body size decreased significantly during at least two ancient global warming events. A new finding that suggests a similar outcome is possible in response to human-caused climate change, according to a University of Michigan paleontologist and his colleagues. Researchers have known for years that mammals such as primates and the groups that include horses and deer became much smaller during a period of warming, called the Paleocene-Eocene Thermal Maximum (PETM), about 55 million years ago.

Now U-M paleontologist Philip Gingerich and his colleagues have found evidence that mammalian "dwarfing" also occurred during a separate, smaller global warming event that occurred about 2 million years after the PETM, around 53 million years ago.

"The fact that it happened twice significantly increases our confidence that we're seeing cause and effect, that one interesting response to global warming in the past was a substantial decrease in body size in mammalian species," said Gingerich, a professor of earth and environmental sciences.

The research team also includes scientists from the University of New Hampshire, Colorado College and the California Institute of Technology. The researchers are scheduled to present their findings Friday, Nov. 1, in Los Angeles at the annual meeting of the Society of Vertebrate Paleontology.

They concluded that decreased body size "seems to be a common evolutionary response" by mammals to extreme global warming events, known as hyperthermals, "and thus may be a predictable natural response for some lineages to future global warming."

The parallels between ancient hyperthermals and modern-day warming make studies of the fossil record particularly valuable, said team member Will Clyde of the University of New Hampshire.

"Developing a better understanding of the relationship between mammalian body size change and greenhouse gas-induced global warming during the geological past may help us predict ecological changes that may occur in response to current changes in Earth's climate," Clyde said.

In 2006, Gingerich proposed that mammalian dwarfing could be a response to the lower nutritional value of plants grown under elevated carbon dioxide levels. Under such conditions, plants grow quickly but are less nutritious than they would normally be.

Animals eating such plants might adapt by becoming smaller over time. Evidence from the ETM2 fossils is consistent with that hypothesis, and research on the topic is ongoing, Gingerich said.

The research was funded by the National Science Foundation (EAR0958821), Geological Society of America, Paleontological Society and Sigma Xi.

Source: University of Michigan

Comment by Dr. Krishna Kumari Challa on November 1, 2013 at 6:19am

Comment by Dr. Krishna Kumari Challa on October 31, 2013 at 8:12am

Comment by Dr. Krishna Kumari Challa on October 31, 2013 at 8:05am

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