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Comment by Dr. Krishna Kumari Challa on December 17, 2014 at 7:28am

Humans First Built Fire 350000 Years Ago
New evidence from an Israeli cave indicates that humans first built fires around 350,000 years ago, according to a new study.

An international team led by Ron Shimelmitz from the University of Haifa examined flint debris and tools discovered in the Tabun Cave in northern Israel. While the study finds archaeological evidence of fire dating back to a million years ago, researchers focus on humans' habitual use of fire.
http://www.academia.edu/8858729/Fire_at_will_The_emergence_of_habit...

The use of fire is central to human survival and to the processes of becoming human. The earliest evi-dence for hominin use of fire dates to more than a million years ago. However, only when fire use became a regular part of human behavioral adaptations could its benefits be fully realized and its evolutionaryconsequences fully expressed. It remains an open question when the use of

fire shifted from occasional and opportunistic to habitual and planned. Understanding the time frame of this 'technological mutation' will help explain aspects of our anatomical evolution and encephalization over the last million years. It will also provide an important perspective on hominin dispersals out of Africa and the colonization of temperate environments, as well as the origins of social developments such as the formation of provi-sioned base camps. Frequencies of burnt flints from a 16-m-deep sequence of archaeological deposits atTabun Cave, Israel, together with data from the broader Levantine archaeological record, demonstratethat regular or habitual fire use developed in the region between 350,000-320,000 years ago. While hominins may have used

fire occasionally, perhaps opportunistically, for some million years, the researchers argue in the paper  that it only became a consistent element in behaviuoral adaptations during the second part of the Middle Pleistocene.

http://www.natureworldnews.com/articles/11176/20141215/humans-first...

Comment by Dr. Krishna Kumari Challa on December 17, 2014 at 7:12am

Merging data on high-energy bursts seen on Earth by NASA's Fermi Gamma-ray Space Telescope with data from ground-based radar and lightning detectors, scientists have completed the most detailed analysis to date of the types of thunderstorms producing terrestrial gamma-ray flashes, or TGFs.
TGFs occur unpredictably and fleetingly, with durations less than a thousandth of a second, and remain poorly understood. Yet the gamma rays they produce rank among the highest-energy light naturally produced on Earth.
Earlier Fermi studies helped uncover lightning-like radio signals emitted by TGFs. This made it possible to use ground-based lightning location networks to pin down storms producing the flashes, opening the door to a deeper understanding of the meteorology powering these extreme events.
Scientists gathered a sample of nearly 900 Fermi TGFs accurately located by ground networks, which can pinpoint the location of lightning discharges -- and the corresponding signals from TGFs -- to within 6 miles (10 km) anywhere on the globe. From this group, they identified 24 TGFs that occurred within areas covered by Next Generation Weather Radar (NEXRAD) sites.
The researchers found that even weak and marginally electrified storms are capable of producing TGFs.
The new study also confirms previous findings indicating that TGFs tend to occur near the highest parts of a thunderstorm, between about 7 and 9 miles (11 to 14 kilometers) high. However, TGFs associated with lightning at lower altitudes would be so weakened by traveling a longer path through the atmosphere that Fermi couldn't detect them. If true, the estimated number of 1,100 TGFs occurring each day may be much larger than previously thought.

Frequent Flyers Could Take a Hit of Radiation from Lightning

Comment by Dr. Krishna Kumari Challa on December 17, 2014 at 7:05am

Superconductivity Record Broken with Rotten-Egg Smelling Compound
Hydrogen sulfide is found to conduct electricity without resistance at a record-high temperature of minus 83 degrees Celsius
http://www.nature.com/news/superconductivity-record-breaks-under-pr...

Comment by Dr. Krishna Kumari Challa on December 17, 2014 at 6:44am

Reproducibility project: cancer biology: Time to do something about reproducibility
Individual scientists, scientific communities and scientific journals can do more to assess the publication of irreproducible results, to promote good science, and to increase the efficiency with which the scientific community self-corrects.

http://elifesciences.org/content/3/e03981?utm_source=content_alert&...

Comment by Dr. Krishna Kumari Challa on December 14, 2014 at 9:04am

'Men Are Idiots,' Says Study In Prestigious Medical Journal
http://www.businessinsider.in/Men-Are-Idiots-Says-Study-In-Prestigi...

Comment by Dr. Krishna Kumari Challa on December 14, 2014 at 8:55am

Invisible 'pain beam' to disperse crowds during disturbances
A long range and non-lethal 'pain beam' weapon that can be used to break up riots or protests from a distance. The Poly WB-1, which was unveiled at an air show in China, uses a millimetre-wave beam that can travel distances of up to one kilometre. When the beam reaches a person, it heats water molecules just below the skin, causing intense pain. While a short burst with the pain beam will cause a human to recoil in pain, longer bursts at certain frequencies will cause the flesh to burn and blister.

The system is very similar to the Active Denial System created by Raytheon, which was sent to Afghanistan but not used in combat due to fears it would fuel enemy propaganda and because it used so much power and took too much time to boot up. In tests of that system, most humans reach their pain threshold within three seconds, and none could withstand longer than five seconds. "For the first millisecond, it just felt like the skin was warming up. Then it got warmer and warmer and you felt like it was on fire ... As soon as you're away from that beam your skin returns to normal and there is no pain," said a spokesman from the Air Force research lab that made the system.

China is developing the weapon for naval the weapon for naval applications to help deal with con frontation in non-lethal ways. There are a number of territorial disputes in the South China and East China seas, involving various islands and boundaries. At the moment, the weapon needs to be attached to a large truck - so no non-lethal ray guns quite yet.

Comment by Dr. Krishna Kumari Challa on December 14, 2014 at 8:49am

Seven mind-scrambling science ideas only geniuses can understand
https://metro.co.uk/2014/12/13/seven-mind-scrambling-science-ideas-...

Comment by Dr. Krishna Kumari Challa on December 14, 2014 at 6:16am

Researchers use real data rather than theory to measure the cosmos
For the first time researchers have measured large distances in the Universe using data, rather than calculations related to general relativity.

A research team from Imperial College London and the University of Barcelona has used data from astronomical surveys to measure a standard distance that is central to our understanding of the expansion of the universe.
-Imperial College London

Comment by Dr. Krishna Kumari Challa on December 12, 2014 at 9:25am

Comment by Dr. Krishna Kumari Challa on December 12, 2014 at 9:03am

Rosetta's new light on Cometary Origins of Earth’s Oceans

The provenance of water and organic compounds on the Earth and other terrestrial planets has been discussed for a long time without reaching a consensus. One of the best means to distinguish between different scenarios is by determining the D/H ratios in the reservoirs for comets and the Earth’s oceans. Here we report the direct in situ measurement of the D/H ratio in the Jupiter family comet 67P/Churyumov-Gerasimenko by the ROSINA mass spectrometer aboard ESA’s Rosetta spacecraft, which is found to be (5.3 ± 0.7) × 10⁻⁴, that is, ~3 times the terrestrial value. Previous cometary measurements and our new finding suggest a wide range of D/H ratios in the water within Jupiter family objects and preclude the idea that this reservoir is solely composed of Earth ocean-like water.

http://www.sciencemag.org/content/early/2014/12/09/science.1261952

In the case of Earth’s oceans, it may not be either comets or asteroids that delivered them, but rather a significant mixture of both.

But the results form Rosetta show comets are not likely to have come through asteroid collisions. The water on Earth has a particular ratio of molecular isotopes - normal water and heavy water - and the water found on 67P has a ratio three times greater. This almost certainly rules out comets as source of earth's water.

Rosetta casts doubt on comets as Earth’s water providers

Comet 67P’s atmosphere contains a surprisingly high fraction of deuterium

https://www.sciencenews.org/article/rosetta-casts-doubt-comets-eart...

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