Knowledge Update

​New York, March 28 (IANS) Scientists have developed a new way to make "polymer nanobrush" -- bristly materials which prevent dust from accumulating on various surfaces.

Polymer brushes have been used to coat everything from eyeglass lenses, boats and medical devices -- where they keep away smudges, damaging chemicals and germs -- to artificial joints and mechanical components in vehicles where they act as a lubricant.

Developed by a team of engineers led by Christopher Li, professor at Drexel University's college of engineering in Philadelphia, it gives scientists a higher degree of control over the shape of the brush and bristles and is much more efficient.

"The past few decades witnessed exciting progresses in studies on polymer brushes, and they show great promises in various fields, including coating, biomedical, sensing, catalysis to name just a few," Li said. 

His approach involves growing a functional two-dimensional sheet of polymer crystals -- similar to a nanoscale piece of double-sided tape. When the sheet is stuck to an existing substrate, and the crystals are dissolved, the remaining polymer chains spring up, forming the bristles of the brush.

"We believe that our discovery of a new way to make polymer brushes is a significant advance in the field and will enable use of the brushes in exciting new ways," added Li in the study published in the journal Nature Communications.

The new brush is the most densely packed polymer brushes to date, with bristles less than a nanometre apart.

Polymer brush materials are especially useful in situations where pieces need to fit tightly together but need to be able to move without friction throwing a wrench in the works. 

These are also effective for keeping important surfaces free of particles, chemicals, proteins and other fouling agents. ​

​New York, March 27 (IANS) Researchers have developed a way to make a magnetic material that could lead to lighter and smaller, cheaper and better-performing high-frequency transformers, needed for more flexible energy storage systems and widespread adoption of renewable energy.

Transportable energy storage and power conversion systems, which can fit inside a single semi-trailer, could make it cost effective to rapidly install solar, wind and geothermal energy systems in even the most remote locations.

"Such modular systems could be deployed quickly to multiple sites with much less assembly and validation time," said one of the researchers Todd Monson from Sandia National Laboratories in the US.

The new manufacturing method enables the creation of transformer cores from raw starting materials in minutes, without decomposing the required iron nitrides, as could happen at the higher temperatures used in conventional method, the researchers said.

Using this method could make transformers up to 10 times smaller than they are currently, Monson said in a statement.

Due to its magnetic properties, iron nitride transformers can be made much more compact and lighter than traditional transformers, with better power-handling capability and greater efficiency.

They will require only air cooling, another important space saver. Iron nitride also could serve as a more robust, high-performance transformer core material for the electrical grid.

So far, Monson and his colleagues have demonstrated the fabrication of iron nitride transformer cores with good physical and magnetic characteristics and now are refining their process and preparing to test the transformers in power-conversion test beds.​

​London, March 27 (IANS) Just one session of a non-invasive brain stimulation technique can reduce core symptoms of anorexia nervosa, including the urge to restrict food intake and feeling fat, says a study.

The researchers assessed whether repetitive transcranial stimulation (rTMS), already an approved treatment for depression, is also effective in reducing symptoms of anorexia.

Up to 20 percent of people with anorexia die prematurely from the disorder and treatments in adults are moderately effective, with only 20-30 per cent of people recovering from the best

"With rTMS we targeted the dorsolateral prefrontal cortex, an area of the brain thought to be involved in some of the self-regulation difficulties associated with anorexia. This technique alters neural activity by delivering magnetic pulses to specific regions of the brain, which feels like a gentle tapping sensation on the side of the head," said first author of the study Jessica McClelland from King's College London.

"We found that one session of rTMS reduced the urge to restrict food intake, levels of feeling full and levels of feeling fat, as well as encouraging more prudent decision-making. Taken together, these findings suggest that brain stimulation may reduce symptoms of anorexia by improving cognitive control over compulsive features of the disorder," McClelland noted.

The findings were published in the journal PLOS ONE.

In the study, 49 people completed food exposure and decision-making tasks, both before and after a session of either real or placebo rTMS. Symptoms of anorexia were measured immediately prior to and following rTMS, as well as 20 minutes and 24 hours after the session.

Compared to the placebo group, they found that participants who had real rTMS showed a tendency for more prudent decision-making.​

​London, March 25 (IANS) Scientists from the University of East Anglia (UEA) have developed a new lip-reading technology that can help in solving crimes and provide communication assistance for people with hearing and speech impairments.

The visual speech recognition technology, created by Dr Helen L. Bear and professor Richard Harvey, can be applied "any place where the audio isn't good enough to determine what people are saying."

Unique problems with determining speech arise when sound isn't available such as on CCTV footage or if the audio is inadequate and there are no clues to give the context of a conversation.

“We are still learning the science of visual speech and what it is people need to know to create a fool-proof recognition model for lip-reading, but this classification system improves upon previous lip-reading methods by using a novel training method for the classifiers,” Dr Bear explained.

Potentially, a robust lip-reading system could be applied in a number of situations from criminal investigations to entertainment.

Lip-reading has been used to pinpoint words footballers have shouted in heated moments on the pitch, but is likely to be of most practical use in situations where are there are high levels of noise, such as in cars or aircraft cockpits.

"Such a system could be adapted for use for a range of purposes like for people with hearing or speech impairments. Alternatively, a good lip-reading machine could be part of an audio-visual recognition system,” Dr Bear added.

Lip-reading is one of the most challenging problems in artificial intelligence so it's great to make progress on one of the trickier aspects “which is how to train machines to recognise the appearance and shape of human lips,” Harvey noted.

The findings were scheduled to be presented at the International Conference on Acoustics, Speech and Signal Processing (ICASSP) in Shanghai on Friday.

The paper was published in the journal Proceedings of the IEEE International Conference on Acoustics, Speech and Signal Processing 2016.​

London, March 25 (IANS) Opening a new window for development of medical approaches to prevent cleft lip and palate, scientists have identified an important gene that is associated with the disfiguring condition.

Increased activity of a gene called GREM1 (Gremlin1) significantly ups the risk for cleft lip and palate, the findings showed.

"The findings reveal a link between GREM1 and specific clinical characteristics that arise in the formation of a cleft lip and palate,” said senior author of the study Heiko Peters from Newcastle University in Britain.

"This is very important in this research area as it helps to decipher the complex interplay between genes required for the different steps and in different tissues during lip and palate development,” Peters noted.

The findings were published in the journal PLoS Genetics.

A cleft is a gap in the upper lip, the roof of the mouth, or sometimes both. Each year, approximately 250,000 babies worldwide are born with a cleft, the study pointed out.

"A cleft lip can occur with or without a cleft palate and the genetic factors that predispose to palate involvement are largely unknown," Peters said.

The research team carried out analyses on genetic and clinical data from three large patient cohorts and identified a strong association between a region on chromosome 15 and cleft lip and palate.

They also carried out studies on mice to investigate where GREM1 is normally active in the development of the face and how alterations in the gene's activity may affect the lip and palate.

Results indicated that it is not the loss of GREM1 function but rather its increased activity that causes the condition.

"These findings provide a framework for further analyses of GREM1 in human cell systems and model organisms, broadening our understanding of the processes that regulate the face's shape," Peters noted.

​An international team of researchers has identified biological markers in the blood that can help doctors predict who is at high risk of developing active tuberculosis (TB).

One-third of the world's population is thought to be infected with Mycobacterium tuberculosis (Mtb), the bacterium that causes tuberculosis, but just a small fraction ever develops symptomatic illness. 

If validated through additional clinical trials, a test based on these blood biomarkers that the researchers have now identified would allow doctors to target therapies to at-risk people, thus preventing them from getting sick.

The decade-long research effort was led by investigators from the South African Tuberculosis Vaccine Initiative at the University of Cape Town, and the Center for Infectious Disease Research, Seattle, US.

The findings were published in the journal The Lancet.

The biomarkers were identified in two stages. First, researchers collected blood samples for two years from more than 6,000 Mtb-infected but otherwise healthy adolescent volunteers in South Africa. 

Analysis of the samples revealed patterns of gene expression that differed between volunteers who eventually developed TB and those who remained healthy. 

This risk "signature," confined to a set of 16 genes, could be detected in a blood sample as early as 18 months before the infected person developed active TB.

Next, the team confirmed the genetic risk signature's predictive ability in a study of more than 4,500 volunteers in South Africa and The Gambia. 

The second study group was more varied in age, health status, ethnicity and exposure to locally common strains of Mtb than volunteers in the first study. 

Despite the differences, the same risk signature found in the first study was detected in the people who eventually developed active TB during the second trial.​

New York, March 26 (IANS)

​Seoul, March 26 (IANS) While it is only natural for birds living among people to learn to differentiate individual humans, researchers have found that skuas living in remote Antarctica too can recognise people who had previously accessed the nests to measure their eggs and nestlings.

The findings suggest that these birds have very high levels of cognitive abilities.

"I had to defend myself against the skuas' attack," said one of the researchers Yeong-Deok Han from Inha University in Incheon, South Korea. 

"When I was with other researchers, the birds flew over me and tried to hit me. Even when I changed my field clothes, they followed me. The birds seemed to know me no matter what I wear," Han noted.

The research team performed a series of experiments. The researchers checked the nests once a week to monitor the breeding status, and the skuas attacked at closer distances with repeated visits of the researchers. 

To test if the birds specifically distinguish the researchers who visited the nests from those who did not, a pair of humans consisting of nest intruder (who accessed the nests) and neutral human (who never accessed the nests before) approached to the nests and walked towards the opposite directions. 

All seven skua pairs followed and tried to attack the nest intruder but never followed the neutral human.

These findings were published in the journal Animal Cognition.

"It is amazing that brown skuas, which evolved and lived in human-free habitats, recognised individual humans just after three or four visits. It seems that they have very high levels of cognitive abilities," lead researcher Won Young Lee, senior researcher from Korea Polar Research Institute, said. ​

​Washington, March 27 (IANS) The Orbital ATK Cygnus cargo ship from NASA was finally bolted into place on the International Space Station's (ISS) Earth-facing port on Sunday.

The spacecraft's arrival will support the crew members' research off the Earth to benefit the Earth.

The spacecraft was delivering more than 7,500 pounds (3,400 kg) of science and research, crew supplies and vehicle hardware to the orbital laboratory to support dozens of nearly 250 science and research investigations that will be carried out during Expeditions 47 and 48.

Beginning with this mission, Cygnus is equipped with a NanoRacks External Cygnus Deployer for CubeSats that will provide opportunities for small satellites to be deployed from Cygnus after the vehicle departs from the ISS.

The spacecraft will spend more than a month attached to the space station before separating from the station.

After completion of its primary ISS resupply mission, Cygnus depart a safe distance from the station before deploying the satellites, and begin its destructive re-entry into Earth's atmosphere in May 2016, disposing of about 3,000 pounds of trash.

The flight was delivering investigations to the space station to study fire, meteors, regolith, adhesion and 3D printing in microgravity.

The "Saffire-I" investigation will provide a new way to study a realistic fire on an exploration vehicle, which has not been possible in the past because the risks for performing such studies on manned spacecraft are too high.

Instruments on the returning Cygnus will measure flame growth, oxygen use and more.

Results could determine microgravity flammability limits for several spacecraft materials, help to validate NASA's material selection criteria, and help scientists understand how microgravity and limited oxygen affect flame size.

A less heated investigation called "Meteor Composition Determination" will enable the first space-based observations of meteors entering Earth's atmosphere from space, the US space agency said in a statement.

A more "grounded" Strata-1 probe will study the properties and behaviour of regolith - the impact-shattered "soil" found on asteroids, comets, the Moon and other airless worlds.

From grounded to gripping, another investigation launching takes its inspiration from small lizards. The "Gecko Gripper" investigation tests a gecko-adhesive gripping device that can stick on command in the harsh environment of space.

Once adhered, the gripper can bear loads up to 20 pounds. The gripper can remain in place indefinitely and can also be easily removed and reused.

From adhesion to additive, the new Additive Manufacturing Facility (AMF) will also be part of the cargo. Additive manufacturing (3D printing) is the process of building a part layer-by-layer, with an efficient use of the material.

The facility is capable of producing parts out of a wide variety of space-rated composites, including engineered plastics.

The ability to manufacture on the orbiting laboratory enables on-demand repair and production capability, as well as essential research for manufacturing on long-term missions.​

​Washington, March 24 (IANS) New NASA-funded research provides evidence that the spin axis of Earth's moon shifted by about five degrees roughly three billion years ago.

The evidence of this motion is recorded in the distribution of ancient lunar ice, evidence of delivery of water to the early solar system."The same face of the moon has not always pointed towards Earth," said Matthew Siegler of the Planetary Science Institute in Tucson, Arizona."As the axis moved, so did the face of the 'man in the moon'. He sort of turned his nose up at the Earth," Siegler noted in a paper appeared in the journal Nature.

Water ice can exist on Earth's moon in areas of permanent shadow.If ice on the moon is exposed to direct sunlight it evaporates into space.

The team show evidence that a shift of the lunar spin axis billions of years ago enabled sunlight to creep into areas that were once shadowed and likely previously contained ice. 

The researchers found that the ice that survived this shift effectively "paints" a path along which the axis moved.

They matched the path with models predicting where the ice could remain stable and inferred the moon's axis had moved by approximately five degrees.

This is the first physical evidence that the moon underwent such a dramatic change in orientation and implies that much of the polar ice on the moon is billions of years old.

"The new findings are a compelling view of the moon's dynamic past," added Yvonne Pendleton, director of NASA's Solar System Exploration Research Virtual Institute (SSERVI) in California.

"It is wonderful to see the results of several missions pointing to these insights," he said.

These findings may open the door to further discoveries on the interior evolution of the moon, as well as the origin of water on the moon and early Earth.​