Knowledge Update

​London, May 7 (IANS) Most people feel that friendship is a two-way street, but only half of your buddies would actually consider you their friend, a study has found, adding that this limits their ability to influence them and further impacts on human behaviour.

Companies and social groups that depend on social influence for collective action, information dissemination and product promotion could improve their strategies and interventions.

"It turns out that we're very bad at judging who our friends are and difficulty in determining the reciprocity of friendship significantly limits our ability to engage in cooperative arrangements," said Erez Shmueli from Tel Aviv University.

“We learned that we can't rely on our instincts or intuition. There must be an objective way to measure these relationships and quantify their impact," Shmueli added in a paper published in the journal PLoS One.

The team conducted extensive social experiments and examined six friendship surveys from some 600 students in Israel, Europe and the United States to assess friendship levels and expectations of reciprocity.

They then developed an algorithm that examines several objective features of a perceived friendship -- the number of common friends or the total number of friends and then distinguish between unidirectional and reciprocal.

The findings showed that 95 percent of participants think that their relationships were reciprocal.

"If you think someone is your friend, you expect him to feel the same way. But in fact that's not the case -- only 50 percent of those polled matched up in the bidirectional friendship category."

"Reciprocal relationships are important because of social influence as influence is the name of the game," Shmueli stated.​

New York, May 7 (IANS) Researchers have developed a new antibody-based drug that has the potential to slow down the replication of the human immunodeficiency virus (HIV) in the body and may also provide a better strategy for long-term control of the deadly infection.

Anti-retroviral therapy -- a combination of drugs that slows the replication of HIV in the body -- currently used to treat HIV has drawbacks. If a person discontinues his or her treatment, even missing a few doses, the level of the virus in the body is able to rebound quickly.

In the antibody therapy, the researchers used 3BNC117 -- a molecule -- also called as a broadly neutralising antibody because it has the ability to fight a wide range of HIV strains.

The findings of the first clinical trial showed that using the antibody could greatly reduce the amount of virus that is present in an individual's blood.

"This study provides evidence that a single dose of an antibody stimulates patients' immune response, enabling them to make new or better antibodies against the virus," said lead author Till Schoofs, postdoctoral fellow at The Rockefeller University in the US. 

For the study, published in the journal Science, the team included 15 patients, in the clinical trial, who had high levels of the virus in their blood, and 12 other patients whose virus levels were being controlled with antiretroviral therapy (ART). 

The patients were infused with a single dose of 3BNC117 and were monitored over a six-month period.

In 14 out of 15 patients who had higher levels of the virus at the time they were given the antibody were seen making new antibodies that could neutralise a number of different strains of HIV.

It usually takes several years for the body to begin to make good antibodies against HIV. So there might be an even better effect later on, especially if patients are given more than one dose of 3BNC117, the researchers added.

To determine further benefits of treatment with 3BNC117, the researchers conducted another study, also published in the journal Science, in a mouse model. 

The results revealed that 3BNC117 was able to engage the animals' immune cells and accelerate their clearance of HIV-infected cells. 

"This shows that the antibody not only can exert pressure on the virus, but also can shorten the survival of infected cells," first author of the study Ching-Lan Lu, doctoral student at The Rockefeller University, noted. 

Further, the researchers plan to test 3BNC117 in combination with other antibodies that target HIV, to determine whether an even stronger antiviral effect can be found. 

New York, May 8 (IANS) Climate change is likely to accelerate rates of chronic kidney disease worldwide as rising temperatures and heat stress harm kidneys.

New findings show that heat stress nephropathy -- chronic kidney diseases are on the rise, especially in many rural communities in hot regions.

With rise in temperature worldwide, dehydration and heat stress are likely to take a toll on the kidneys, emerging as a major cause of poor kidney health in the near future.

"A new type of kidney disease, occurring throughout the world in hot areas, is linked with temperature and climate and may be one of the first epidemics due to global warming," said Richard Johnson, from the University of Colorado in the US.

Also, global warming and a rise in extreme heat waves have increased the risk of kidney disease, especially for the agricultural workers, who are exposed to the heat for longer duration.

Decreasing amounts of rain contribute to the growing epidemic of the chronic kidney disease consistent with heat stress -- by reducing water supplies and quality as temperatures rise, the researchers noted.

"We were able to connect increased rates of chronic kidney disease in different areas to an underlying mechanism -- heat stress and dehydration -- and to climate," Johnson said.

The findings will be detailed in forthcoming issue of the Clinical Journal of the American Society of Nephrology (CJASN).

Governments and scientists need to work together to learn more about this threat and take action to reduce the risk of climate change-linked kidney disease, the researchers said.​

Washington, May 8 (IANS) NASA's MESSENGER mission has unveiled the first global digital elevation model (DEM) of Mercury, revealing in stunning detail the topography across the entire innermost planet.

It will also pave the way for scientists to fully characterise Mercury's geologic history.

"The wealth of these data has already enabled and will continue to enable exciting scientific discoveries about Mercury for decades to come," said Susan Ensor, software engineer at The Johns Hopkins University's Applied Physics Laboratory (APL).

This new model reveals a variety of interesting topographic features, including the highest and lowest points on the planet.

The highest elevation on Mercury is at 4.48 km above Mercury's average elevation, located just south of the equator in some of Mercury's oldest terrain.

The lowest elevation, at 5.38 km below Mercury's average, is found on the floor of Rachmaninoff basin, an intriguing double-ring impact basin suspected to host some of the most recent volcanic deposits on the planet.

More than 100,000 images were used to create the new model.

"This has become one of my favourite maps of Mercury. Now that it is available, I'm looking forward to it being used to investigate this epic volcanic event that shaped Mercury's surface," added Nancy Chabot, instrument scientist for the Mercury Dual Imaging System (MDIS) in a NASA statement.

"During its four years of orbital observations, MESSENGER revealed the global characteristics of one of our closest planetary neighbours for the first time.

The data from the mission will continue to be utilised by the planetary science community for years to come.​

New York, May 8 (IANS) Introducing a noise net around airfields that emit sound levels equivalent to those of a conversation in a busy restaurant could prevent collisions between birds and aircraft, saving lives and billions in damages, new research has found.

Filling a controlled area with acoustic noise around an airfield, where the majority of collisions tend to take place, can reduce the number of birds in the area by 80 percent, the findings showed.

"We are using a different kind of deterrent - trying to stop birds from hearing one another by playing a noise that is at the same pitch as the alarm calls or predator noises they are listening out for," said lead researcher John Swaddle, professor of biology at College of William and Mary in Williamsburg, US.

"By playing a noise at the same pitch, we mask those sounds, making the area much riskier for the birds to occupy. The birds don't like it and leave the area around the airfields, where there is potential for tremendous damage and loss of life," Swaddle noted.

The researchers set up speakers and amplifiers in three areas of an airfield in Virginia state and observed bird abundance over eight weeks, the first four weeks without noise and the second four weeks with the noise turned on.

Results showed a large decrease in the number of birds in the 'sonic net' and areas just outside and found that it was particularly effective at deterring a number of species that were at high risk of bird strike such as starlings.

"We have conducted prior research in an aviary but this is the first study done out in the field to show the efficacy of the sonic net," Swaddle, who is also a visiting research associate at University of Exeter in Britain, said.

The study was published in the journal Ecological Applications.

Bird strikes cost the aviation industry worldwide billions of dollars annually, and were responsible for 255 deaths between 1988 and 2013, yet measures to reduce these have been largely ineffective, the study noted.

Techniques to deter birds from airports include shooting, poisoning, live-capture and relocation, and the use of scare technologies, but these have proved largely ineffective.​

​New York, May 9 (IANS) Researchers have developed a device with the potential of shortening the time required to rapidly diagnose bacterial infections from days to a couple of hours.

The system could also allow point-of-care diagnosis, as it does not require the facilities and expertise available only in hospital laboratories, the study said. 

"Health-care-associated infections are a major problem that affects more than 600,000 patients each year, more than 10 percent of whom will die, and incurs more $100 billion in related costs," said co-senior author of the study Ralph Weissleder from Massachusetts General Hospital (MGH) in Boston, US.

"Rapid and efficient diagnosis of the pathogen is a critical first step in choosing the appropriate antibiotic regimen, and this system could provide that information in a physician's office in less than two hours," Weissleder noted.

The system developed by the MGH team, dubbed PAD for Polarization Anisotropy Diagnostics, allows for accurate genetic testing in a simple device. 

In this study, the team used a prototype PAD system to test clinical samples from nine patients and compared the results with those acquired by conventional microbiology cultures. 

Testing for the presence of five important bacterial species -- E. coli, Klebsiella, Acinetobacter, Pseudomonas, and Staph aureus -- and for factors indicating the virulence and antibiotic resistance of specific strains produced identical results with both procedures. 

But while PAD provided results in less than two hours, the bacterial culture process took three to five days. 

The findings were reported in the journal Science Advances.

"We can see three immediate applications for a system that can provide such rapid and accurate results - quickly diagnosing a patient's infection, determining whether antibiotic-resistant bacteria are present in a group of patients, and detecting bacterial contamination of medical devices or patient environments," co-senior author Hakho Lee, associate professor of radiology at Harvard Medical School, pointed out.​

New York, May 6 (IANS) Scientists from the Massachusetts Institute of Technology (MIT) have compiled a comprehensive list of potential gases to guide search for life on exoplanets.

Biosignature gases emitted by exoplanetary life forms could be detected remotely by space telescopes but these gases might have quite different compositions from those in the Earth's atmosphere.

“This work reminds me of Charles Darwin's voyage aboard 'The Beagle', exploring the vast diversity of life by sailing around the world," said Nancy Y Kiang, scientist at NASA's Goddard Institute for Space Studies. 

“In the search for life beyond our planet, we are currently at a similarly exciting, early but rapidly evolving stage of exploration as the discovery of exoplanets accelerates,” he added.

Instead of netting strange creatures from the bottom of the sea, the authors searched and found thousands of curious, potentially biogenic gas molecules. 

“These will inspire a new body of research into identifying also larger molecules, investigating their origin and fate here, and their potential expression on exoplanets as signs of life,” Kiang added.

This approach maximises the chances of identifying planets orbiting nearby stars that support life.

According to S Seager, W Bains and J.J. Petkowski from MIT and Rufus Scientific from the University of Cambridge in a paper published in the journal Astrobiology, all stable and potential volatile molecules should be considered as possible biosignature gases.

Beijing, May 6 (IANS) Chinese archaeologists said they have found a paddy field more than 8,000 years old. This could be the earliest wet rice farming site in the world.

The field, covering less than 100 square metres, was discovered at the neolithic ruins of Hanjing in Jiangsu province in November 2015, Xinhua quoted a spokesman with the archaeology institute of Nanjing Museum as saying.

At a seminar held in late April to discuss findings at the Hanjing ruins, 70 scholars from universities, archaeology institutes and museums in China concluded that the wet rice field was the oldest ever discovered.

Researchers with the institute found that the field was divided into parts with different shapes, each covering less than 10 square metres.

They also found carbonised rice that was confirmed to have grown more than 8,000 years ago based on carbon dating as well as evidence that the soil was repeatedly planted with rice.

Lin Liugen, head of the institute, said Chinese people started to cultivate rice about 10,000 years ago and carbonised rice of the age has been found in the past but paddy remnants were quite rare.​

​London, May 6 (IANS) Insulin when taken in conjunction with metformin -- a cheap and common drug that helps control blood sugar levels -- has the potential to reduce mortality risk and heart attacks in people with Type 2 diabetes, a new study has found.

"In this research we found that there was a considerable reduction in deaths and heart problems when this cheap and common drug was used in conjunction with insulin,” said lead author Craig Currie, professor at Cardiff University in Britain.

Increased dosage of insulin has been previously known to raise the risk of cancer, heart attacks and mortality. 

But the findings have shown that metformin can attenuate the risks associated with insulin.

However, according to researchers, there was no difference in the risk of cancer between people treated with insulin as a single therapy or in combination with metformin.

The retrospective research, published in the journal PLOS ONE, looked at people with Type 2 diabetes who were treated with insulin with or without metformin from the year 2000 onwards. 

12,020 people were identified from a general practice data source, and the research team tracked them for three-and-a-half years on average, from the time they were first prescribed insulin.

"While this research indicates the potential of using these treatments together, further studies are needed to determine the risks and benefits of insulin in Type 2 diabetes and the possible benefits associated with the administration of metformin alongside insulin," Currie concluded.

New York, May 6 (IANS) It is possible for us to intentionally forget past experiences by changing how we think about the context of those memories, says a study.

The findings have a range of potential applications centred on enhancing desired memories, such as developing new educational tools, or diminishing harmful memories, including treatments for post-traumatic stress disorder.

Memory theorists have known for long that we use context -- or the situation we are in, including sights, sounds, smells, where we are, who we are with -- to organise and retrieve our memories. 

But this study wanted to explore whether and how people can intentionally forget past experiences. 

The researchers showed participants images of outdoor scenes, such as forests, mountains and beaches, as they studied two lists of random words.

The study's participants were told to either forget or remember the random words presented to them interspersed between scene images. 

"We used fMRI ( functional magnetic resonance imaging) to track how much people were thinking of scene-related things at each moment during our experiment. That allowed us to track, on a moment-by-moment basis, how those scene or context representations faded in and out of people's thoughts over time," said study lead author Jeremy Manning, assistant professor at Dartmouth College in New Hampshire, US.

Right after they were told to forget, the fMRI showed that they "flushed out" the scene-related activity from their brains.

"It's like intentionally pushing thoughts of your grandmother's cooking out of your mind if you don't want to think about your grandmother at that moment," Manning said. 

"We were able to physically measure and quantify that process using brain data," Manning noted.

But when the researchers told participants to remember the studied list rather than forget it, this flushing out of scene-related thoughts did not occur. 

Further, the amount that people flushed out scene-related thoughts predicted how many of the studied words they would later remember, which shows the process is effective at facilitating forgetting.

The study appeared in the journal Psychonomic Bulletin and Review.​