Knowledge Update

New York, June 9 (IANS) Scientists have discovered that hair-like filaments on the surface of Geobacter bacteria exhibit electrical conductivity comparable to that of copper -- paving the way for the employment of biological materials in nanoscale electron devices.

Scientists from the University of Massachusetts at Amherst used X-ray diffraction to analyse the structure of the filaments called the pili. 

They found that the electronic arrangement and small molecular separation distances of less than 0.3 nanometres give the pili an excellent conductivity.

Although proteins are usually electrically insulating, the researchers said the study supports the concept that the pili of G. sulfurreducens represent a novel class of electronically functional proteins in which aromatic amino acids promote long-distance electron transport.

The research findings, published recently in the journal mBio, can provide useful feedback for studies targeting the enhancement of pili's electrical conductivity through genetic engineering.

It could subsequently be used to construct low-cost, non-toxic, nanoscale, biological sources of electricity for light-weight electronics and for bioremediation.​

​London, June 6 (IANS) Researchers have successfully identified the four keys that unlock the genetic code of skin cells and reprogramme them to start producing red blood cells instead.

The findings could lead to personalised red blood cells for those in need of blood transfusion, for instance, people suffering from chronic anemia -- a condition in which the patient has an insufficient amount of red blood cells.

"This is the first time anyone has ever succeeded in transforming skin cells into red blood cells, which is incredibly exciting," said lead author of the study Sandra Capellera from Lund University in Sweden.

"We have performed this experiment on mice, and the preliminary results indicate that it is also possible to reprogramme skin cells from humans into red blood cells,” Johan Flygare, who is also from Lund University, noted.

The study was published in the journal Cell Reports.

Every individual has a unique genetic code, which is a complete instruction manual describing exactly how all the cells in the body are formed. 

This instruction manual is stored in the form of a specific DNA sequence in the cell nucleus. All human cells -- brain, muscle, fat, bone and skin cells -- have the exact same code. 

The thing that distinguishes the cells is which chapter of the manual the cells are able to read. 

The research team wanted to find out how the cells open the chapter that contains instructions on how to produce red blood cells. 

Here is how the researchers got the skin cells to open the chapter describing red blood cells.

With the help of a retrovirus, they introduced different combinations of over 60 genes into the skin cells' genome, until one day they had successfully converted the skin cells into red blood cells. 

The study showed that out of 20,000 genes, only four are necessary to reprogramme skin cells to start producing red blood cells. Also, all four are necessary in order for it to work.​

New York, June 7 (IANS) Pandas do not like it hot and rising temperatures can also put pressure on their food supply by eliminating vast amounts of bamboo plants, researchers say.

"Higher climate temperatures would upset the entire system in the panda reserves and the wild, eliminating vast amounts of bamboo," said one of the researchers James Spotila, Professor at Drexel University in Philadelphia, Pennsylvania, US.

But burning out food sources is not the only problem when it comes to climate change. Rising temperatures are bad for pandas themselves, the researchers noted.

Giant pandas experience heat stress when temperatures climb above 25 degrees Celsius.

"They have to live at temperatures below that to stay healthy," Spotila said. 

"In nature, they actively seek out cool areas (microhabitats) in summer and move to higher elevations to avoid heat," he noted.

Working at the Chengdu Research Base in China, home of roughly 150 giant pandas, the researchers discovered that they have bigger appetites than originally believed.

Metabolism of pandas was actually just a little below what would be expected for a mammal of their size. Their rates were on-par for bears and came in just a little below seals, kangaroos and deer, the findings showed.

But past research placed the pandas' metabolism at a much lower rate.

The researchers believe that although the metabolism of giant pandas is higher than previously reported, there is more than enough bamboo in nature to keep pandas healthy and happy for years. That is, until rising global temperatures kill the plants off.

The findings were reported in the journal Scientific Reports.

"Unchecked climate change will undo all of the years of hard work by the Chinese to save their national icon," Spotila said.​

​New York, June 7 (IANS) Scientists have discovered a ‘third gene' that leads to the development of the common neurodegenerative disease, a study said.

The study provided evidence that mutations in gene TMEM230 caused Parkinson's disease -- a disorder of the central nervous system that affects movement, often including tremors.

“The study showed that mutations in this new gene lead to pathologically and clinically proven cases of the disease," said led researcher Teepu Siddique, Professor at Northwestern University in the US.

The findings showed that the gene is responsible for producing a protein involved in packaging the neurotransmitter dopamine in neurons. Loss of dopamine-producing neurons is a defining characteristic of Parkinson's disease.

Also, individuals with this gene mutation showed both clinical characteristics of the disease -- symptoms like tremors, slow movement and stiffness -- as well as pathological evidence in the brain -- loss of dopamine neurons and abnormal accumulations of proteins inside surviving neurons.

"This particular gene causing Parkinson's disease is not just limited to one population in North America," Siddique said.

"It's worldwide, found in very different ethnic and environmental conditions. These mutations are that strong."

Further, TMEM230 was also found to encode a protein that extends across the membrane of tiny sacks inside neurons called synaptic vesicles, which store neurotransmitters before they are released from one cell to another.

The scientists hypothesised that the protein is involved in the movement of these vesicles.

"We believe that vesicle trafficking defects are a key mechanism of Parkinson's disease, not just for cases with this mutation, but a common pathway for the majority of cases," added Han-Xiang Deng, Professor at Northwestern University. 

"Our new findings suggest normalising synaptic vesicle trafficking may be a strategy for future therapeutic development. We can develop drugs to promote this critical pathway," Deng noted in the paper detailed in the journal Nature Genetics.

In the study, which stretched for 20 long years, the researchers performed genome-wide analysis on 65 members of a family, including 13 with the disease, in hopes of finding a common mutation that could explain the prevalence.​

​Beijing, June 7 (IANS) Concerned over increasing health problems, China has decided to provide 'family doctors' to every household in the country by 2020.

The State Council's Medical Reform Office said 200 cities will come under the service in 2016. In the following year, it plans to provide the facility to about 30 percent of China's population.

With a population of about 1.4 billion, of which 9 percent is elderly, China is faced with rising health problems such as cancer and obesity among others.

The problems have to do with various factors which range from pollution to sedentary lifestyle.

In 2015, over four million people were diagnosed with cancer and nearly three million died from it.

Family doctors are expected to serve as health guards for Chinese people, Xinhua news agency reported, quoting the National Health and Family Planning Commission.

A health official said the move will reduce healthcare costs and make it more accessible to public.

The doctors, to be put into services, will be from local hospitals and clinics and rural areas.

The public healthcare system is overburdened in China, which is faced with a shortage of doctors. The burgeoning middle class has given rise to growing privatization in the health sector.

According to state-run newspaper Global Times, there was an acute shortage of pediatrician in China: an average of 0.53 doctors for every 1,000 children.

According to WHO, China had 1.9 physicians per 1,000 people.

China ranked 95th globally in health expenditure per capita in 2013, according to the most recent World Bank data.​

​London, June 7 (IANS) Despite having a much simpler and smaller brain than that of primates, fish have the remarkable ability to distinguish between human faces, new research has found.

“Being able to distinguish between a large number of human faces is a surprisingly difficult task, mainly due to the fact that all human faces share the same basic features,” said first author Cait Newport from Oxford University.

“It has been hypothesised that this task is so difficult that it can only be accomplished by primates, which have a large and complex brain,” Newport noted.

To test this idea, the researchers wanted to determine if another animal with a smaller and simpler brain, and with no evolutionary need to recognise human faces, was still able to do so.

In the study, archerfish -- a species of tropical fish well known for its ability to spit jets of water to knock down aerial prey -- were presented with two images of human faces and trained to choose one of them using their jets. 

The fish were then presented with the learned face and a series of new faces and were able to correctly choose the face they had initially learned to recognise. 

They were able to perform this task even when more obvious features, such as head shape and colour, were removed from the images.

The fish were highly accurate when selecting the correct face, reaching an average peak performance of 81 per cent in the first experiment (picking the previously learned face from 44 new faces) and 86 per cent in the second experiment (in which facial features such as brightness and colour were standardised).

The study was published in the journal Scientific Reports.

“Once the fish had learned to recognize a face, we then showed them the same face, as well as a series of new ones. In all cases, the fish continued to spit at the face they had been trained to recognize, proving that they were capable of telling the two apart,” Newport said.

“The fact that archerfish can learn this task suggests that complicated brains are not necessarily needed to recognise human faces,” Newport noted.​

​London, June 7 (IANS) Astrophysicists from the University of Birmingham have captured the sounds of some of the oldest stars in our Milky Way galaxy, a study says.

The findings could help researchers understand how our galaxy formed and evolved.

"We were thrilled to be able to listen to some of the stellar relics of the early universe,” said lead researcher Andrea Miglio.

The researchers reported the detection of resonant acoustic oscillations of stars in 'M4', one of the oldest known clusters of stars in the galaxy, some 13 billion years old.

"The stars we have studied really are living fossils from the time of the formation of our Galaxy, and we now hope be able to unlock the secrets of how spiral galaxies, like our own, formed and evolved,” Miglio noted.

Using data from the NASA Kepler/K2 mission, the team studied the resonant oscillations of stars using a technique called asteroseismology. 

These oscillations lead to miniscule changes or pulses in brightness, and are caused by sound trapped inside the stars. By measuring the tones in this 'stellar music', it is possible to determine the mass and age of individual stars.

The findings published in the journal Monthly Notices of the Royal Astronomical Society open the door to using asteroseismology to study the very early history of our galaxy.

"Just as archaeologists can reveal the past by excavating the earth, so we can use sound inside the stars to perform Galactic archaeology,” Professor Bill Chaplin said.​

New York, June 7 (IANS) Scientists have developed a new tool to modify brain activity and memory in targeted ways, without the help of any drugs or chemicals.

The new tool is a protein that can be encoded in animal genomes to effectively switch off their inhibitory synapses -- connections between neurons -- increasing their electrical activity.

The GFE3 protein may help researchers map the brain's connections and better understand how inhibitory synapses modulate brain function, said lead author Don Arnold, Professor at University of Southern California.

It also may enable them to control neural activity and lead to advancements in research for diseases or conditions ranging from schizophrenia to cocaine addiction, Arnold said.

"GFE3 harnesses a little known and remarkable property of proteins within the brain," Arnold said.

The protein takes advantage of an intrinsic process -- the brain's cycle of degrading and replacing proteins.

Most brain proteins last only a couple of days before they are actively degraded and replaced by new proteins. GFE3 targets proteins that hold inhibitory synapses together to this degradation system and as a result, the synapses fall apart.

"Rather than a cell deciding when a protein needs to be degraded, we sort of hijack the process," Arnold explained.

For the study, published in the journal Nature Methods, the team of scientists studied the protein's effect in both mice and zebrafish. 

The researchers found that GFE3 protein triggered the neurons on the two sides of the spine to work in opposition, generating uncoordinated movements.

Drugs could be used to inhibit inhibitory synapses in the brain, for instance benzodiazapines, which treat anxiety, insomnia or seizures. 

"Unfortunately, cells that have very different, even opposite functions tend to be right next to each other in the brain," Arnold said. 

"Thus, pharmacological experiments are especially difficult to interpret. By encoding GFE3 within the genome, we can target and modulate the inhibitory synapses of specific cells without affecting other cells that have different functions," Arnold noted.​

​London, June 6 (IANS) Finnish scientists have recovered important metals -- lithium, cobalt and nickel -- from battery waste with nearly 100 per cent purity.

Recovered metals could be used in the manufacture of batteries, and in the future especially in batteries of electric vehicles.

Researchers from Lappeenranta University of Technology (LUT) were able to extract cobalt at 99.6 per cent purity, nickel at 99.7 per cent purity, and lithium at 99.9 per cent purity from battery waste. 

"The manufacturing of new batteries requires metals of particularly high purity. If the purity of lithium is below 99.5 per cent, it is not suitable as raw material for batteries. In other words, the difference between 99.4 per cent and 99.9 per cent purity is very significant," said one of the researchers Sami Virolainen.

The findings were presented at the 'Circular Materials' conference organised by Chalmers University of Technology in Gothenburg, Sweden.

Lithium and cobalt are increasing in importance because they are needed in batteries of electronic devices and especially in electric cars. 

Forecasts indicate that the global need for lithium may quadruple between the years 2011 and 2025. 

The study separated metals through a liquid-liquid extraction process on a pilot scale. In the process, extraction takes place between two liquid phases which do not dissolve in each other. 

All other impurities are separated from the solution, leaving only lithium, cobalt and nickel. 

Previous studies have attempted to extract all three metals, but have only succeeded in extracting two at a relatively high purity and the third with low purity, the study said.

"As a separation process, liquid-liquid extraction is a viable option when nearly 100 per cent purity and a high recovery rate are required," Virolainen noted.​

​Washington, June 6 (IANS) Using 29 years of data from satellite imageries, NASA scientists have found extensive greening in the Arctic region, thanks to rising temperatures.

The northern reaches of North America are getting greener, said the study that provides the most detailed look yet at plant life across Alaska and Canada. 

In a changing climate, almost a third of the land cover -- much of it Arctic tundra -- is looking more like landscapes found in warmer ecosystems, the researchers said.

With 87,000 images taken from Landsat satellites, the researchers found that western Alaska, Quebec and other regions became greener between 1984 and 2012. 

Landsat is a joint NASA/US Geological Survey programme that provides the longest continuous space-based record of the Earth's land vegetation in existence.

"It shows the climate impact on vegetation in the high latitudes," said one of the researchers Jeffrey Masek from NASA's Goddard Space Flight Center in Greenbelt, Maryland. 

Temperatures are warming fast in the Arctic which has led to longer seasons for plants to grow in and changes to the soils. 

Overall, the scientists found that 29.4 percent of the region greened up, especially in shrublands and sparsely vegetated areas, while 2.9 percent showed vegetation decline.

The findings were reported in the journal Remote Sensing of Environment.

Landsat, like other satellite missions, can use the amount of visible and near-infrared light reflected by the green, leafy vegetation of grasses, shrubs and trees to characterize the vegetation. 

Then, with computer programs that track each individual pixel of data over time, researchers can see if an area is greening -- if more vegetation is growing, or if individual plants are getting larger and leafier. 

If, however, the vegetation becomes sparser, the scientists would classify that area as browning.​