Knowledge Update

​Washington, May 19 (IANS) The US Labour Department has agreed to increase overtime rates for workers amid a continuing shrinking of the middle class.

The rule will increase protection of over 4.2 million workers by doubling the payment threshold for working over 40 hours a week from $455 per week to $913 dollars, Xinhua

​London, May 18 (IANS) Individuals suffering from chronic fatigue tend to be more anxious, distressed and are also more likely to suppress these emotions than people who do not have this condition, says a study.

In addition, when under stress, chronic fatigue syndrome patients show greater activation of the biological "fight or flight" mechanism, which may add to their fatigue, the study said.

"Patients with chronic fatigue syndrome often tell us that stress worsens their symptoms, but this study demonstrates a possible biological mechanism underlying this effect," said lead study author Katharine Rimes from King's College London. 

The findings appeared in the journal Health Psychology.

The research that involved examining 160 people in Britain relied on self and observer reports, as well as physiological responses that were collected before, during or after the participants watched a distressing film clip. 

Half of the participants had been diagnosed with chronic fatigue syndrome while the rest were healthy.

Half of each group were instructed to suppress their emotions and half were told to express their feelings as they wished. 

The researchers measured skin conductance in participants because this increases with greater sweating, which is a sign of activation of the body's sympathetic nervous system. This is often known as the biological fight or flight system used to cope with stress.

Regardless of the instruction they received, the chronic fatigue syndrome participants reported higher anxiety and sadness, and their skin responses indicated they were more distressed than the healthy control group, both before and after the film. 

"These findings may help us understand why some chronic fatigue syndrome patients don't seek out social support at times of stress," Rimes stated.​

​London, May 18 (IANS) Don't pluck that flower at night for the plant might be sleeping after a long day in the sun, suggests new research that measured the changes in the shape of plants during the day and night cycle.

Most living organisms adapt their behaviour to the rhythm of day and night. Plants are no exception: Flowers open in the morning, some tree leaves close during the night. And while researchers have been studying the day and night cycle in plants for a long time, nobody knew whether trees too go to sleep.

To find out, the team of researchers from Austria, Finland and Hungary measured the movement of fully grown trees using laser scanners.

"Our results show that the whole tree droops during night, which can be seen as position change in leaves and branches," said Eetu Puttonen from Finnish Geospatial Research Institute.

"The changes are not too large, only up to 10 cm for trees with a height of about 5 metres, but they were systematic and well within the accuracy of our instruments," Puttonen said.

To rule out effects of weather and location, the experiment was done twice with two different trees. 

The first tree was surveyed in Finland and the other in Austria. 

Both tests were done close to solar equinox, under calm conditions with no wind or condensation. 

The leaves and branches were shown to droop gradually, with the lowest position reached a couple of hours before sunrise. In the morning, the trees returned to their original position within a few hours. 

However, it is not yet clear whether they were "woken up" by the sun or by their own internal rhythm.

The findings appeared in the journal Frontiers in Plant Science.

The researchers noted that laser scanners use infrared light, which is reflected by the leaves. With this scanning technique, a full-sized tree can be automatically mapped within minutes with sub-centimeter resolution.

"We believe that laser scanning point clouds will allow us to develop a deeper understanding of plant sleep patterns and to extend our measurement scope from individual plants to larger areas, like orchards or forest plots," Norbert Pfeifer from Vienna University of Technology in Austria said.​

​Beijing, May 18 (IANS) Chinese scientists have found fossils of the world's oldest known multi-cellular organisms, dating back as far as 1.56 billion years, nearly one billion years earlier than previously estimated.

The research published on Wednesday in the journal "Nature Communications" showed the fossils were found in carbon-rich compressions in China's Hebei province. The biggest was 30 cm long and eight cm wide, Xinhua news agency reported.

Zhu Maoyan, the lead researcher, said the Yanshan Mountain region has Mesoproterozoic sedimentary mudstone. Organic fragments extracted from the host rock show well-preserved multi-cellular cell structures.

Zhu said multi-cellular life with modest diversity existed in the early Mesoproterozoic seas, but the species' affinity to extant species remains unclear.

"Further research will shed light on the ancient marine ecosystem," he said.

Prior to this discovery, fossils of multi-cellular life only dated back some 600 million years.

The new fossils show organisms large enough to be visible to the naked eye and predate the diversification of multi-cellular life by nearly one billion years.​

London, May 19 (IANS) Current rates of climate change could trigger instability in a major Antarctic glacier, ultimately leading to nearly three metre rise of the sea level, say researchers.

The scientists looked at the future of Totten glacier, a significant glacier in Antarctica that drains one of the world's largest areas of ice, on the East Antarctic Ice Sheet (EAIS).

By studying the history of Totten's advances and retreats, the researchers discovered that if climate change continues unabated, the glacier could cross a critical threshold within the next century, entering an irreversible period of very rapid retreat.

This would cause it to withdraw up to 300 kilometres inland in the following centuries and release vast quantities of water, contributing up to 2.9 metres to global sea-level rise.

"The evidence coming together is painting a picture of East Antarctica being much more vulnerable to a warming environment than we thought," said study co-author Martin Siegert, professor at Imperial College London.

"This is something we should worry about. Totten Glacier is losing ice now, and the warm ocean water that is causing this loss has the potential to also push the glacier back to an unstable place," Siegert noted.

The East Antarctic Ice Sheet is currently thought to be relatively stable in the face of global warming compared with the much smaller ice sheet in West Antarctica, but Totten Glacier is bucking the trend by losing substantial amounts of ice. 

The new research revealed that Totten Glacier may be even more vulnerable than previously thought.

The findings were published in the journal Nature. 

To uncover the history of Totten Glacier's movements, the team looked at the sedimentary rocks below the glacier using airborne geophysical surveys. 

From the geological record, influenced by the erosion by ice above, they were able to understand the history of the glacier stretching back millions of years.

The researcehrs found that the glacier has retreated more quickly over certain 'unstable' regions in the past. 

Based on this evidence, the scientists believe that when the glacier hits these regions again we will see the same pattern of rapid retreat.​

​Washington, May 19 (IANS) April 2016 was the 12th consecutive month a monthly global temperature record has been broken, the US government's climate agency said on Wednesday.

"This is the longest such balmy streak in the 137-year record, which dates back to 1880," Xinhua quoted the US National Oceanic and Atmospheric Administration (NOAA) as saying.

"The heat goes on -- and so do the records," the agency added.

For April, the average temperature across global land and ocean surfaces was 1.98 degrees Fahrenheit (1.10 degrees Celsius) above the 20th century average of 56.7 degrees Fahrenheit (13.7 degrees Celsius), according to the monthly report released by the NOAA.

This temperature departure from average was not only the highest for the month of April in the 1880-2016 record, but also the fourth-highest among all months on record, behind March 2016, February 2016, and December 2015, said the report.

On land, all six continents had at least a top nine warm April, with South America, Africa, and Asia observing a record high average temperature for April, the NOAA report said.

Only northeastern Canada and southern South America were cooler than average, with the most notable cool temperature departures across northeastern Canada.

Overall, "April 2016 was characterised by warmer to much warmer-than-average conditions across most of Earth's land surfaces," it concluded.

The globally averaged sea surface temperature for April was also highest for this month on record and surpassed the same period in 1998 by 0.43 degrees Fahrenheit (0.24 degrees Celsius) -- the last time a similar strength El Nino occurred.

This April also saw the the smallest Northern Hemisphere snow cover extent recorded in 50 years of snow-cover data collection.

For the four months of 2016, the average temperature for the globe was 2.05 degrees Fahrenheit (1.14 degrees Celsius) above the 20th-century average of 54.8 degrees Fahrenheit (12.7 degrees Celsius), the report added.​

Sydney, May 18 (IANS) Australian researchers have created a device that has set a new world record for solar efficiency, the media reported on Wednesday.

The device traps light through a simple prism, which dramatically bolsters the efficiency of solar cells, Xinhua news agency reported.

Researchers from the University of New South Wales (UNSW) Martin Green and Mark Keevers said the device extracts the maximum energy from sunlight, using a hybrid four-junction receiver to squeeze even more electricity from each beam of sunlight.

"This encouraging result shows there are still advances to come in photovoltaics research to make solar cells even more efficient," said Keevers.

"Extracting more energy from every beam of sunlight is critical to reducing the cost of electricity generated by solar cells as it lowers the investment needed, and delivering payback faster."

The pair set a new world record for sunlight-to-electricity conversion efficiency at 34.5 percent.

"What's remarkable is that this level of efficiency had not been expected for many years," said Green.

"A recent study by Germany's Agora Energiewende think tank set an aggressive target of 35 percent efficiency by 2050 for a module that uses unconcentrated sunlight, such as the standard ones on family homes."

The efficiency of commercially available solar panels is said to range between 14 to 22 percent.

"So things are moving faster in solar cell efficiency than many experts expected, and that's good news for solar energy," Green added.

"But we must maintain the pace of photovoltaic research in Australia to ensure that we not only build on such tremendous results, but continue to bring benefits back to Australia."​

​New York, May 18 (IANS) A genetic switch that is turned on in the brain during fasting helps halt the spread of intestinal bacteria into the bloodstream, says a new study.

The study shows a molecular pathway by which the brain communicates with the gastrointestinal (GI) tract to prevent unnecessary activation of the immune system during fasting by strengthening the barrier against gut microbes. 

The discovery of this brain-gut signal in fruit flies, which has many parallels to humans, could eventually inform the treatment of inflammatory bowel diseases in people, said the study published in the journal Proceedings of the National Academy of Sciences.

In addition to its role in promoting the absorption of nutrients from food, the GI tract is host to a panoply of bacteria. These microbes actually help in the digestive process by producing chemicals that break down complex fats and carbohydrates.

"Fasting has a positive value that spills over not just into the metabolic system, but also inflammation and brain function," said the study's lead investigator Marc Montminy, professor at Salk Institute for Biological Studies in La Jolla, California, US.

"Understanding how the gut maintains this barrier, and creating drugs to enhance that barrier, may have important benefits for people with inflammatory bowel disease," Montminy noted.

The new study is part of an ongoing research to pin down the mechanisms that a genetic switch in the brain called Crtc uses to control energy balance. ​

​Toronto, May 18 (IANS) Researchers, including one of Indian origin, have developed a device that can dramatically reduce the time and cost required for detecting the deadly E. coli bacteria in drinking water.

Some kinds of E. coli can cause diarrohea, while others cause urinary tract infections, respiratory illness and pneumonia, and other illnesses, according to the US Centres for Disease Control and prevention.

"We have developed a hydrogel based rapid E. coli detection system that will turn red when E. coli is present,” said Sushanta Mitra, professor at York University in Toronto.

"It will detect the bacteria right at the water source before people start drinking contaminated water,” Mitra said.

The new technology can cut down the time taken to detect E. coli from a few days to just a couple of hours. 

It is also an inexpensive way to test drinking water (Rs.155 per test estimated), which is a boon for many developing countries, the researchers said.

"This is a significant improvement over the earlier version of the device, the Mobile Water Kit, that required more steps, handling of liquid chemicals and so on,” Mitra noted.

"The entire system is developed using a readily available plunger-tube assembly. It’s so user-friendly that even an untrained person can do the test using this kit,” he added.

Traditional methods of testing for E. coli contamination involves collecting water samples to send to an appropriate microbiological lab where the bacteria is cultured before a plate count is done to detect E. coli presence.

The testing device uses the porous hydrogel matrix, developed by Mitra’s team at his Micro & Nano-scale Transport Laboratory that cages specific enzymatic substrates that release certain enzymes in E. coli cells. 

These enzymes then chemically react with the substrates to change colour. If there is no E. coli, the colour of the hydrogel won’t change, as there is no chemical reaction.

The results of the water test can be instantly broadcast using a mobile app already developed by the team​

​New York, May 18 (IANS) Are you over 50 and remain wearily busy? If yes, take heart. A new study says older adults with a busy daily lifestyle tend to have better mental functioning than their less busy peers.

The findings showed that at any age, and regardless of education, a busier lifestyle can lead to superior processing speed of the brain, working memory, reasoning, and vocabulary. 

"We show that people who report greater levels of daily 'busyness' tend to have better cognition, especially with regard to memory for recently learned information," said lead author Sara Festini, postdoctoral researcher at University of Texas in the US.

Also, the busiest an individual is, the better can be his/her episodic memory -- the ability to remember specific events in the past.

Busy people are likely to have more opportunities to learn as they are exposed to more information and encounter a wider range of situations in daily life. 

However, it is also possible that people with better mental functioning seek out a busier lifestyle, or that busyness and cognition reinforce each other, resulting in reciprocal strengthening, the researchers said. 

For the study, published in the journal Frontiers in Aging Neuroscience, the team surveyed 330 healthy women and men between 50 and 89.

The participants took part in a long series of neuropsychological tests to measure their cognitive performance.

"Living a busy lifestyle appears beneficial for mental function, although additional experimental work is needed to determine if manipulations of busyness have the same effect," Festini noted.​