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Comment by Dr. Krishna Kumari Challa on September 26, 2014 at 5:45am

Comment by Dr. Krishna Kumari Challa on September 25, 2014 at 9:28am

'Time dilation' predicted by Einstein confirmed by lithium ion experiment.

Physicists have verified a key prediction of Albert Einstein’s special theory of relativity with unprecedented accuracy. Experiments at a particle accelerator in Germany confirm that time moves slower for a moving clock than for a stationary one.

The work is the most stringent test yet of this ‘time-dilation’ effect, which Einstein predicted. One of the consequences of this effect is that a person travelling in a high-speed rocket would age more slowly than people back on Earth.

Few scientists doubt that Einstein was right. But the mathematics describing the time-dilation effect are “fundamental to all physical theories”, says Thomas Udem, a physicist at the Max Planck Institute for Quantum Optics in Garching, Germany, who was not involved in the research. “It is of utmost importance to verify it with the best possible accuracy.”

The paper was published on September 16 in Physical Review Letters. It is the culmination of 15 years of work by an international group of collaborators including Nobel laureate Theodor Hänsch, director of the Max Planck optics institute.

To test the time-dilation effect, physicists need to compare two clocks — one that is stationary and one that moves. To do this, the researchers used the Experimental Storage Ring, where high-speed particles are stored and studied at the GSI Helmholtz Centre for heavy-ion research in Darmstadt, Germany.
http://www.nature.com/news/special-relativity-aces-time-trial-1.15970

Comment by Dr. Krishna Kumari Challa on September 24, 2014 at 11:45am

Comment by Dr. Krishna Kumari Challa on September 24, 2014 at 6:40am

Winners of the 2014 Google Science Fair
Ciara, Émer and Sophie were named the Grand Prize Winner and the 15-16 age category winners of our fourth annual Google Science Fair. They are some of thousands of students ages 13-18 who dared to ask tough questions like: How can we stop cyberbullying? How can I help my grandfather who has Alzheimer's from wandering out of bed at night? How can we protect the environment? And then they actually went out and answered them.
18 finalists representing nine countries—Australia, Canada, France, India, Russia, U.K., Ukraine and the U.S.—who spent today impressing Googlers and local school students at our Mountain View, Calif. headquarters. In addition to our Grand Prize Winners, the winners of the 2014 Google Science Fair are:

13-14 age category: Mihir Garimella (Pennsylvania, USA) for his project FlyBot: Mimicking Fruit Fly Response Patterns for Threat Evasion. Like many boys his age, Mihir is fascinated with robots. But he took it to the next level and actually built a flying robot, much like the ones used in search and rescue missions, that was inspired by the way fruit flies detect and respond to threats. Mihir is also the winner of the very first Computer Science award, sponsored by Google.
17-18 age category: Hayley Todesco (Alberta, Canada) for her project Waste to Water: Biodegrading Naphthenic Acids using Novel Sand Bioreactors. Hayley became deeply interested in the environment after watching Al Gore’s documentary “An Inconvenient Truth.” Her project uses a sustainable and efficient method to break down pollutant substances and toxins found in tailing ponds water in her hometown, a hub of the oil sands industry.
The Scientific American Science in Action award: Kenneth Shinozuka (Brooklyn, New York) for his wearable sensors project. Kenneth was inspired by his grandfather and hopes to help others around the world dealing with Alzheimer's. The Scientific American award is given to a project that addresses a health, resource or environmental challenge.
Voter’s Choice award: Arsh Dilbagi (India) for his project Talk, which enables people with speech difficulties to communicate by simply exhaling.
As the Grand Prize winners, Ciara, Émer and Sophie receive a 10-day trip to the Galapagos Islands provided by National Geographic, a $50,000 scholarship from Google, a personalized LEGO prize provided by LEGO Education and the chance to participate in astronaut training at the Virgin Galactic Spaceport in the Mojave desert.
- Google Blog

Teens show off inventions at Google Science Fair

http://abc7news.com/technology/teens-show-off-inventions-at-google-...

Comment by Dr. Krishna Kumari Challa on September 24, 2014 at 6:33am

Active invasion of bacteria into living fungal cells
The rice seedling blight fungus Rhizopus microsporus and its endosymbiont Burkholderia rhizoxinica form an unusual, highly specific alliance to produce the highly potent antimitotic phytotoxin rhizoxin. Yet, it has remained a riddle how bacteria invade the fungal cells. Genome mining for potential symbiosis factors and functional analyses revealed that a type 2 secretion system (T2SS) of the bacterial endosymbiont is required for the formation of the endosymbiosis. Comparative proteome analyses show that the T2SS releases chitinolytic enzymes (chitinase, chitosanase) and chitin-binding proteins. The genes responsible for chitinolytic proteins and T2SS components are highly expressed during infection. Through targeted gene knock-outs, sporulation assays and microscopic investigations we found that chitinase is essential for bacteria to enter hyphae. Unprecedented snapshots of the traceless bacterial intrusion were obtained using cryo-electron microscopy. Beyond unveiling the pivotal role of chitinolytic enzymes in the active invasion of a fungus by bacteria, these findings grant unprecedented insight into the fungal cell wall penetration and symbiosis formation.
http://elifesciences.org/content/3/e03007

Comment by Dr. Krishna Kumari Challa on September 24, 2014 at 6:26am

T cell-specific inhibition of multiple apoptotic pathways blocks negative selection and causes autoimmunity

T cell self-tolerance is thought to involve peripheral tolerance and negative selection, involving apoptosis of autoreactive thymocytes. However, evidence supporting an essential role for negative selection is limited. Loss of Bim, a Bcl-2 BH3-only protein essential for thymocyte apoptosis, rarely results in autoimmunity on the C57BL/6 background. Mice with T cell-specific over-expression of Bcl-2, that blocks multiple BH3-only proteins, are also largely normal. The nuclear receptor Nur77, also implicated in negative selection, might function redundantly to promote apoptosis by associating with Bcl-2 and exposing its potentially pro-apoptotic BH3 domain. Here, we report that T cell-specific expression of a Bcl2 BH3 mutant transgene results in enhanced rescue of thymocytes from negative selection. Concomitantly, Treg development is increased. However, aged BH3 mutant mice progressively accumulate activated, autoreactive T cells, culminating in development of multi-organ autoimmunity and lethality. These data provide strong evidence that negative selection is crucial for establishing T cell tolerance.
http://elifesciences.org/content/3/e03468#sthash.vBgMe7lK.dpuf

Comment by Dr. Krishna Kumari Challa on September 24, 2014 at 6:19am

Epidemiology: Mapping Ebola in wild animals for better disease control
Identifying the regions where wild animal populations could transmit the Ebola virus should help with efforts to prepare at-risk areas for future outbreaks.
http://elifesciences.org/content/3/e04565

Mapping the zoonotic niche of Ebola virus disease in Africa

Ebola virus disease (EVD) is a complex zoonosis that is highly virulent in humans. The largest recorded outbreak of EVD is ongoing in West Africa, outside of its previously reported and predicted niche. We assembled location data on all recorded zoonotic transmission to humans and Ebola virus infection in bats and primates (1976–2014). Using species distribution models, these occurrence data were paired with environmental covariates to predict a zoonotic transmission niche covering 22 countries across Central and West Africa. Vegetation, elevation, temperature, evapotranspiration, and suspected reservoir bat distributions define this relationship. At-risk areas are inhabited by 22 million people; however, the rarity of human outbreaks emphasises the very low probability of transmission to humans. Increasing population sizes and international connectivity by air since the first detection of EVD in 1976 suggest that the dynamics of human-to-human secondary transmission in contemporary outbreaks will be very different to those of the past.

http://elifesciences.org/content/3/e04395

Comment by Dr. Krishna Kumari Challa on September 23, 2014 at 5:35am

Generation of Macroscopic Singlet States in a Cold Atomic Ensemble
http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.113.093601 Quantum Entanglement Creates New State of Matter
Half a million ultracold atoms were linked together in the first-ever “macroscopic spin singlet” state.
Physicists have used a quantum connection Albert Einstein called “spooky action at a distance” to link 500,000 atoms together so that their fates were entwined. The atoms were connected via “entanglement,” which means an action performed on one atom will reverberate on any atom entangled with it, even if the particles are far apart. The huge cloud of entangled atoms is the first “macroscopic spin singlet,” a new state of matter that was predicted but never before realized.

Comment by Dr. Krishna Kumari Challa on September 21, 2014 at 2:47pm

Top 50 science stars of Twitter:
http://news.sciencemag.org/scientific-community/2014/09/top-50-scie...

Comment by Dr. Krishna Kumari Challa on September 20, 2014 at 9:18am

Source diversity among journals cited in Science Times
A content analysis of The New York Times’ Science Times section from 1998 to 2012 found evidence of increased source diversity in use of scientific journals as news sources. Science Times increased the frequency at which it cited journals, the number of different journals that it cited, and the number of disciplines represented by cited journals. The results suggest that online availability of a wide array of scientific journals has changed sourcing behaviors.

http://pus.sagepub.com/content/early/2014/07/24/0963662514542908.ab...

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