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Comment by Dr. Krishna Kumari Challa on February 13, 2017 at 6:46am

LIGO Can Also Make Gravitational Waves

It's been almost a year now since the Laser Interferometer Gravitational-Wave Observatory (LIGO) announced the greatest scientific discovery of 2016.

Though the first gravitational waves were actually detected in September 2015, it was only after additional detections were made in June 2016 that LIGO scientists finally confirmed that the elusive waves exist, solidifying Albert Einstein's major prediction in his theory of relativity.

Now, the most sensitive detector of spacetime ripples in the world turns out to also be the best producer of gravitational waves.

"When we optimise LIGO for detection, we also optimise it for emission [of gravitational waves]," said physicist Belinda Pang from the California Institute of Technology (Caltech) in Pasadena according to a report in Science.

Pang was speaking at a meeting of the American Physical Society last week, representing her team of physicists.

Gravitational waves are ripples that are produced when massive objects warp spacetime.

They essentially stretch out space, and according to Einstein, they can be produced by certain swirling configurations of mass. Using uber-sensitive twin detectors in Hanford, Washington, and Livingston, Louisiana, LIGO is able to detect this stretching of space.

Once they realised they could detect gravitational waves, the physicists posited that the sensitivity of their detectors would enable them to efficiently generate these ripples, too.

Comment by Dr. Krishna Kumari Challa on February 3, 2017 at 6:48am

Health effects of long-duration spaceflight can have on the human body: A new study has found that space travel can change the volume of gray matter in different parts of the brain, which may be a result of fluids shifting due to a lack of gravity, and the brain working overtime to relearn the basics of movement in a strange new environment.

Humans evolved to thrive in conditions here on Earth, so it's not surprising that once taken beyond our home turf, we're subjected to a range of health issues. Without gravity constantly pushing down on the body, bones and muscles can lose mass over time, an issue that astronauts on the International Space Station (ISS) try to mitigate through rigorous exercise regimes. Cosmic radiation can also be a serious hazard once we leave the protection of the Earth's electromagnetic field, and early results from an ongoing NASA study has found that long stays in space can actually alter a person's DNA.

This new study, conducted by researchers at the University of Michigan, focused on the brain. The team took MRI scans of 26 astronauts – 12 of which stayed just two weeks as shuttle crew members, while the other 14 lived on the ISS for six months. In all cases, the volume of gray matter increased and decreased in different parts of the brain, and the longer the astronauts spent in space, the more dramatic those changes were.

Researchers found large regions of gray matter volume decreases, which could be related to redistribution of cerebrospinal fluid in space. Gravity is not available to pull fluids down in the body, resulting in so-called puffy face in space. This may result in a shift of brain position or compression. Fluid displacement due to a lack of gravity has been known to cause all sorts of health issues for space travellers, most notably blurry vision. But on the plus side, one of the most marked increases in gray matter occurred in the parts of the brain responsible for controlling and sensing the legs. This, the researchers propose, could be due to the fact that moving in zero gravity is a completely different experience to getting around on Earth, meaning the astronauts are essentially learning to walk all over again. The researchers aren't sure exactly what's going on in the brain when the changes occur, but it may be the result of neurons creating new connections. A follow-up study will examine what effects these changes may have on a person's cognition and brain function, as well as how long these changes may last after returning to Earth.

The research was published in the journal Nature Microgravity.

Comment by Dr. Krishna Kumari Challa on January 31, 2017 at 8:14am

RNA clay offers green alternative to plant pesticides

• RNA clay is a promising non-GM technology that may replace pesticides

• Virus-specific RNA only kills the targeted pathogen when sprayed onto plants

• Several companies are already working on commercialising RNA clay

A nano-sized bio-degradable clay-comprising double stranded ribonucleic acid (dsRNA) could offer a cost-effective, clean and green alternative to chemical-based plant pesticides.
 
Australian researchers from the University of Queensland have successfully used a gene-silencing spray, named BioClay, a combination of biomolecules and clay, to protect tobacco plants from a virus for 20 days with a single application. Their study has been published in Nature Plants.
 
“When BioClay is sprayed onto a plant, the virus-specific dsRNA is slowly released from the clay nanosheets into the plant. This activates a pathway in the plant that is a natural defence mechanism. The dsRNA is chopped up into small bits of RNA by enzymes of this pathway. These small bits attack the virus when it infects the plant without altering the plant genome”. 

Comment by Dr. Krishna Kumari Challa on January 31, 2017 at 6:04am

Rising temperatures could boost toxic mercury levels in fish by up to seven times the current rates, say Swedish researchers.

They’ve discovered a new way in which warming increases levels of the toxin in sea creatures.

In experiments, they found that extra rainfall drives up the amount of organic material flowing into the seas.

This alters the food chain, adding another layer of complex organisms which boosts the concentrations of mercury up the line. The study has been published in the journal, Science Advances.

Comment by Dr. Krishna Kumari Challa on January 29, 2017 at 11:12am

Joint Statements on Climate Change from National Academies of Science Around the World

A joint statement issued by the Australian Academy of Sciences, Royal Flemish Academy of Belgium for Sciences and the Arts, Brazilian Academy of Sciences, Royal Society of Canada, Caribbean Academy of Sciences, Chinese Academy of Sciences, French Academy of Sciences, German Academy of Natural Scientists Leopoldina, Indian National Science Academy, Indonesian Academy of Sciences, Royal Irish Academy, Accademia Nazionale dei Lincei (Italy), Academy of Sciences Malaysia, Academy Council of the Royal Society of New Zealand, Royal Swedish Academy of Sciences, Turkish Academy of Sciences, and Royal Society (UK).

National academies of sciences from around the world have published formal statements and declarations acknowledging the state of climate science, the fact that climate is changing, the compelling evidence that humans are responsible, and the need to debate and implement strategies to reduce emissions of greenhouse gases. Not a single national science academy disputes or denies the scientific consensus around human-caused climate change. A few examples of joint academy statements since 2000 on climate are listed here. Many national academies have, in addition, published their own reports and studies on climate issues. 

The Science of Climate Change (Statement of 17 National Science Academies, 2001)

http://science.sciencemag.org/content/292/5520/1261

Comment by Dr. Krishna Kumari Challa on January 28, 2017 at 7:11am

Doomsday clock advanced!

It's now 2 ½ minutes to “midnight,” according to the Bulletin of Atomic Scientists, which warned Thursday that the end of humanity may be near.

The group behind the famed Doomsday Clock announced at a news conference that it was adjusting the countdown to the End of it All by moving the hands 30 seconds closer to midnight — the closest the clock has been to Doomsday since 1953, after the United States tested its first thermonuclear device, followed months later by the Soviet Union's hydrogen bomb test.

In announcing that the Doomsday Clock was moving 30 seconds closer to the end of humanity, the group noted that in 2016, “the global security landscape darkened as the international community failed to come effectively to grips with humanity’s most pressing existential threats, nuclear weapons and climate change.”

But the organization also cited the election of President Trump in changing the symbolic clock.

The scientists' message: Climate change exists...there are no alternative facts here.

 “This already-threatening world situation was the backdrop for a rise in strident nationalism worldwide in 2016, including in a US presidential campaign during which the eventual victor, Donald Trump, made disturbing comments about the use and proliferation of nuclear weapons and expressed disbelief in the overwhelming scientific consensus on climate change.”

Comment by Dr. Krishna Kumari Challa on January 27, 2017 at 9:29am

Scientists at The Scripps Research Institute (TSRI) have announced the development of the first stable semisynthetic organism. Building on their 2014 study in which they synthesized a DNA base pair, the researchers created a new bacterium that uses the four natural bases (called A, T, C and G), which every living organism possesses, but that also holds as a pair two synthetic bases called X and Y in its genetic code.

TSRI Professor Floyd Romesberg and his colleagues have now shown that their single-celled organism can hold on indefinitely to the synthetic base pair as it divides. Their research was published January 23, 2017, online ahead of print in the journal Proceedings of the National Academy of Sciences.

 

Comment by Dr. Krishna Kumari Challa on January 27, 2017 at 9:21am

Scientists to oppose Donald Trump in huge ‘March for Science’ in Washington

The demonstration will be in opposition to the administration’s plans to delete climate change data and gag scientists

Scientists are going to march on the White House to try and force Donald Trump to recognise climate change.

Following the Women’s Marches held around the world on the day after Donald Trump’s inauguration – and widely thought to be the biggest mobilisation in the history of the US – various groups are now organising a “March for Science”. Tens of thousands of people have indicated that they will attend the protest, which is set to happen both in Washington DC and across the United States.

The event will not be restricted specifically to scientists but to “anyone who values empirical science”, and not specifically to professional scientists.

The group behind it intends to announce a date and a platform as soon as it can, and is expected to do so before the end of the month. 

https://www.facebook.com/marchforscience/

Comment by Dr. Krishna Kumari Challa on January 25, 2017 at 7:07am

Scientists have discovered 'smart cancer cells' - and realized why a type of breast cancer drug stops working in some patients. The early-stage findings, from an international team led by Imperial College London and the European Institute of Oncology in Milan, reveal some breast tumours evolve to make their own 'fuel supply', rendering treatments powerless.

The team, whose findings are published in the journal Nature Genetics, hope their work will increase treatment options for patients whose cancer has returned.

Around 70 per cent of breast cancers are so-called ER positive, which means the cancer cells contain a receptor for the hormone oestrogen. It is this hormone that fuels the tumours.

Patients with this type of cancer are offered one of two drugs after surgery to prevent the cancer coming back.

One of these drugs, called tamoxifen, prevents oestrogen from binding to DNA in cancer cells, while the second type of treatment, called aromatase inhibitors, prevents residual oestrogen from being produced in other tissues.

However both tamoxifen and aromatase inhibitors stop working in around one in three patients.

Scientists assumed the tumours developed resistance in some way.

in the latest study, the team discovered that in one in four patients taking aromatase inhibitors, the tumours had increased production of aromatase in the cancer cells. The tumours appear to do this by increasing the number of aromatase genes, in a process called amplification.

This allowed the cancer cells to effectively make their own oestrogen, without relying on external sources of the hormone, explained Dr Luca Magnani, co-lead author of the research from the Department of Surgery and Cancer at Imperial: “For the first time we have seen how breast cancer tumours become resistant to aromatase inhibitors. The treatments work by cutting off the tumour’s fuel supply – oestrogen – but the cancer adapts to this by making its own fuel supply.”

The researchers also discovered that tumours become resistant in different ways, depending on whether tamoxifen or aromatase inhibitors are used.

Almost none of the tumours in patients taking tamoxifen had increased production of aromatase to boost their oestrogen supply - and the team are now planning further studies into how cancer cells become resistant to tamoxifen.

http://www.nature.com/ng/journal/vaop/ncurrent/full/ng.3773.html?WT...

Comment by Dr. Krishna Kumari Challa on January 25, 2017 at 6:47am

Cities eating into world’s farm lands

• By 2030 the world could lose 30 million hectares of farm lands to cities

• Asia and Africa accounts for 80 per cent of the losses with China as worst hit

• Forest lands will likely be converted to replace the losses in agricultural lands

By 2030, the world could lose millions of fertile agricultural lands to expanding cities with Asia and Africa accounting for 80 per cent of the total farm losses, a study finds.
 
Analysing satellite data on croplands and their productivity using year 2000 as the reference point and comparing it with urban area projections for 2030, international researchers found that 30 million hectares of crop lands will be lost to growing cities – an area equivalent to the Philippines. Of this, Asia and Africa will lose 24 million hectares of prime agricultural land.

With cities becoming hubs of economic activity, large-scale changes are expected. However, the authors say this is the first study to quantify the effect of urbanisation on crop lands at global, continental, and country levels. The study was carried out by researchers from Austria, Germany, Sweden, New Zealand, and United States.
 
The croplands that are going to disappear by 2030 have productivity that is almost twice the global average and accounted for about 3—4 per cent of global crop production in 2000.
 
China, India, Nigeria, Pakistan, and the US top countries set to lose cropland to urbanisation. The productivity of rice, wheat, maize, and soybean are most likely to be affected, though there are significant variations at regional levels.

http://www.pnas.org/content/early/2016/12/20/1606036114

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