Knowledge Update

New York, March 22 (IANS) Many of the species now perishing due to the ongoing sixth mass-extinction event -- especially the smaller ones -- may vanish without a permanent trace, says researchers.

The fossil record is much more durable than any human record, said one of the researchers Roy Plotnick, professor of earth and environmental sciences at University of Illinois at Chicago, US.

"There are species going extinct today that have never been described," Plotnick said.

"Others are going extinct that are known only because someone wrote it down," Plotnick noted.

All such species would thus be unknown in the far future, he said, if the written historical record is lost -- as it might well be.

Animals least likely to be found as fossils are "the small, cute and fuzzy ones, like rodents and bats", Plotnick said. 

"Body size is an obvious factor -- bigger things tend to leave a fossil record, as do things with larger geographical ranges," he pointed out.

For the study, the researchers compared the "Red List" of endangered species with several ecological databases of living species and three paleontological databases of catalogued fossils. 

"Comparing the current biodiversity crisis, often called the 'sixth extinction,' with those of the geological past requires equivalent data," Plotnick pointed out.

They ran a statistical analysis to indicate which threatened species were most likely to disappear with no mark of their existence.

The researchers were shocked to find that more than 85 percent of the mammal species at high risk of extinction lack a fossil record. 

And those at highest risk have about half the probability of being incorporated into the fossil record compared to those at lower risk, the researchers said.​

​London, March 22 (IANS) An international team of archaeologists have revealed that culture played a major role in the significant increase of pottery production at the end of the last Ice Age.

Invented in Japan around 16,000 years ago, production of pottery increased vastly 11,500 years before, coinciding with a shift to a warmer climate. 

Increase in production of pottery was previously attributed to changing climate, resurgence in forests and increase in vegetation and animals, which led to new food sources becoming available.

As a result, ancient Japanese developed different cooking and storage techniques for the wider variety of foodstuffs available. The thinking goes that their shifting eating habits demanded new pottery.

However, the results of the study showed that the pottery was used largely for cooking marine and freshwater animal species - a routine that remained constant despite climate warming and new resources becoming available.

"Here, we are starting to acquire some idea of why pottery was invented and became such a successful technology. Interestingly, the reason seems to be little to do with subsistence and more to do with the adoption of a cultural tradition, linked to celebratory occasions and competitive feasting, especially involving the preparation of fish and shellfish,” said one of the researchers Oliver Craig, director at University of York in Britain.

This functional resilience in pottery use, in the face of climatic changes, suggested that cultural influences rather than environmental factors are more important in the widespread uptake of pottery, the researchers maintained in the journal Proceedings of the National Academy of Sciences.

The team analysed 143 ceramic vessels from Torihama, an ancient site in western Japan and performed molecular and isotopic analysis of lipids extracted from these vessels, which spanned a 9000-year period.

The findings showed that the hunter-gatherer survived mostly on different types of marine and freshwater animal species -- fish and shellfish.

Only a little evidence of plant processing in pottery, or cooking of animals such as deer was found.

"The preservation of lipids on ceramic material of this antiquity is remarkable. The analysis provides the first insights into how pottery use changed during massive climate change at the end of the last Ice Age," said first author Alexandre Lucquin, research associate at the York University.

"The findings prompt a new phase of ceramic research in East Asia, highlighting the need for widespread organic analysis of our long, rich and varied pottery records," said Shinya Shoda, a visiting research fellow from Nara National Research Institute for Cultural Properties who participated in the study. 

The last Ice Age peaked about 21,000 years ago and ended around 11,500 years ago.​

Toronto, March 22 (IANS) Life in the city changes cognition, behaviour and physiology of birds to their advantage, making those living in urban environments far more superior than the ones from rural environments.

City birds have adapted to their urban environments enabling them to exploit new resources more favourably then their rural counterparts, the researchers said. 

The study that aimed to find clear cognitive differences in birds from urbanised compared to rural areas, reported key differences in problem-solving abilities such as opening drawers to access food, and temperament (bolder) among city birds versus country birds.

The team tested the two groups of birds using not only associative learning tasks, but innovative problem solving tasks. 

Innovativeness is considered to be useful in the "real life" of animals in the wild, more so than associative learning.

"We found that not only were birds from urbanised areas better at innovative problem-solving tasks than bullfinches from rural environments, but that surprisingly urban birds also had a better immunity than rural birds," said first author of the study Jean-Nicolas Audet from McGill University in Montreal, Canada.

The work was conducted using bullfinches captured from various parts of the Caribbean island.

The findings were published in the journal Behavioral Ecology.

"Since urban birds were better at problem-solving, we expected that there would be a trade-off and that the immunity would be lower, just because we assumed that you can't be good at everything' (in fact, both traits are costly). It seems that in this case, the urban birds have it all," Audet said.​

​New York, March 23 (IANS) By looking at the physics behind the speeding up or slowing down of a stars rotation, its x-ray activity, and magnetic field generation, researchers have developed a new conceptual framework for understanding how stars similar to our Sun evolve.

The work could "ultimately help to determine the age of stars more precisely than is currently possible", said study first author Eric Blackman, professor of physics and astronomy at the University of Rochester in New York, US.

The new model, published in the journal Monthly Notices of the Royal Astronomical Society, helps explain how stellar rotation, activity, magnetic field, and mass loss all mutually evolve with age, the researchers explained.

Using our Sun as the calibration point, the model accurately described the likely behaviour of the Sun in the past, and how it would be expected to behave in the future. 

"Our model shows that stars younger than our Sun can vary quite significantly in the intensity of their x-ray emission and mass loss," Blackman said. 

"But there is a convergence in the activity of the stars after a certain age, so you could say that our Sun is very typical for stars of its mass, radius, and its age. They get more predictable as they age," Blackman noted.

"We're not yet at the point where we can accurately predict a star's precise age, because there are simplifying assumptions that go into the model," Blackman said. 

"But in principle, by extending the work to relax some of these assumptions we could predict the age of for a wide range of stars based on their x-ray luminosity," Blackman explained.

At the moment, empirically determining the age of stars is most easily accomplished if a star is among a cluster of stars, from whose mutual properties astronomers can estimate the age.

But its age can then be estimated "to an accuracy not better than a factor of 25 percent of its actual age, which is typically billions of years", Blackman explained. 

The problem is worse for "field stars," alone in space such that the cluster method of dating cannot be used. 

The new model provides a physics explanation for how stellar rotation, activity, magnetic field, and mass loss all mutually evolve with age.

"Only by tackling the entire problem of how stellar rotation, x-ray activity, magnetic field and mass-loss mutually affect each other could we build a complete picture," study co-author James Owen, NASA Hubble fellow at Institute for Advanced Study in Princeton, New Jersey, explained.​

Sydney, March 23 (IANS) The day when you can look tidy even without washing your clothes does not seem too distant as researchers, including one of Indian origin, have developed a technology to make textiles clean themselves within less than six minutes when put them under a light bulb or out in the sun.

The researchers at RMIT University in Melbourne, Australia, have developed a cheap and efficient new way to grow special nanostructures -- which can degrade organic matter when exposed to light -- directly onto textiles.

"There's more work to do to before we can start throwing out our washing machines, but this advance lays a strong foundation for the future development of fully self-cleaning textiles," said researcher Rajesh Ramanathan.

The research paper was published in the journal Advanced Materials Interfaces.

The work paves the way towards nano-enhanced textiles that can spontaneously clean themselves of stains and grime simply by being put under light.

The process developed by the team had a variety of applications for catalysis-based industries such as agrochemicals, pharmaceuticals and natural products, and could be easily scaled up to industrial levels, Ramanathan said.

"The advantage of textiles is they already have a 3D structure so they are great at absorbing light, which in turn speeds up the process of degrading organic matter," he explained.

The researchers worked with copper and silver-based nanostructures, which are known for their ability to absorb visible light.

When the nanostructures are exposed to light, they receive an energy boost that creates "hot electrons". 

These "hot electrons" release a burst of energy that enables the nanostructures to degrade organic matter.

The challenge for researchers has been to bring the concept out of the lab by working out how to build these nanostructures on an industrial scale and permanently attach them to textiles.

The RMIT team's novel approach was to grow the nanostructures directly onto the textiles by dipping them into a few solutions, resulting in the development of stable nanostructures within 30 minutes.

When exposed to light, it took less than six minutes for some of the nano-enhanced textiles to spontaneously clean themselves.

"Our next step will be to test our nano-enhanced textiles with organic compounds that could be more relevant to consumers, to see how quickly they can handle common stains like tomato sauce or wine," Ramanathan said.​

​London, March 21 (IANS) In a first, researchers have shown that a fungus can transform manganese into a mineral composite with favourable electrochemical properties - paving the way for a better rechargeable battery in the near future.

The findings suggest that fungus Neurospora crassa present in a red bread mold could be the key to producing more sustainable electrochemical materials for use in rechargeable batteries

“We have made electrochemically active materials using a fungal manganese biomineralisation process," said Geoffrey Gadd from the University of Dundee in Scotland. 

The electrochemical properties of the carbonised fungal biomass-mineral composite were tested in a supercapacitor and a lithium-ion battery.

The compound was found to have excellent electrochemical properties. This system, therefore, suggests a novel biotechnological method for the preparation of sustainable electrochemical materials.

Gadd and his colleagues have long studied the ability of fungi to transform metals and minerals in useful and surprising ways. 

In earlier studies, they showed that fungi could stabilise toxic lead and uranium. 

That led the researchers to wonder whether fungi could offer a useful alternative strategy for the preparation of novel electrochemical materials too.

“We had the idea that the decomposition of such biomineralised carbonates into oxides might provide a novel source of metal oxides that have significant electrochemical properties," Gadd added in a paper published in the Cell Press journal Current Biology.

“We were surprised that the prepared biomass-Mn oxide composite performed so well,” he noted. 

In comparison to other reported manganese oxides in lithium-ion batteries, the carbonised fungal biomass-mineral composite "showed an excellent cycling stability and more than 90 percent capacity was retained after 200 cycles," the authors noted.

The team will continue to explore the use of fungi in producing various potentially useful metal carbonates. ​

London, March 20 (IANS) They say that once you have learned to ride a bicycle, you never forget how to do it. But discovery of a new brain mechanism suggests that while learning, the brain also actively tries to forget apparently to make space for new memories to form.

"This is the first time that a pathway in the brain has been linked to forgetting, to actively erasing memories," said one of the researchers Cornelius Gross from European Molecular Biology Laboratory (EMBL).

"One explanation for this is that there is limited space in the brain, so when you are learning, you have to weaken some connections to make room for others," Gross said.

"To learn new things, you have to forget things you have learned before," Gross explained.

The study was published in the journal Nature Communications.

At the simplest level, learning involves making associations, and remembering them. Working with genetically engineered mice, Gross and colleagues studied the hippocampus, a region of the brain that is long been known to help form memories.

Information enters this part of the brain through three different routes. As memories are cemented, connections between neurons along the 'main' route become stronger.

When the scientists blocked this main route, the connections along it were weakened, meaning the memory was being erased.

Interestingly, this active push for forgetting only happens in learning situations. When the scientists blocked the main route into the hippocampus under other circumstances, the strength of its connections remained unaltered.​

New York, March 20 (IANS) Scientists have found the internet-based Chinese language version of the Intolerance of Uncertainty Scale (IUS), which is used to evaluate a person's fear of the unknown, is as good as the traditional paper-and-pencil test.

A team of researchers from Beijing Forestry University, the Hong Kong Institute of Education and Beijing Normal University checked the validity of the internet-based Chinese IUS and concluded that it is "excellent within-test consistency and re-test reliability".

Their analysis, described in the journal Cyberpsychology, Behaviour, and Social Networking, said the online test is appropriate for use, and is comparable to the paper-and-pencil version in terms of the psychological and personality-related traits it reveals. 

The tests are useful in assessing psychological factors that may be predictive of anxiety, depression, eating disorders, and a range of other negative coping strategies. ​

​New York, March 20 (IANS) A team of US researchers has developed a new imaging technique for viewing cells and tissues in three dimensions under the skin, which may one day allow doctors to evaluate how cancer cells are responding to treatment.

The technique, called MOZART, was developed by researchers at the Stanford University in California, which shows intricate real-time details in three dimensions of the lymph and blood vessels in a living animal. 

"We've been trying to look into the living body and see information at the level of the single cell," said Adam de la Zerda, assistant professor at Stanford and senior author of the study. "Until now there has been no way do that," he added.

The research, according to the university, could one day allow scientists to detect tumours in the skin, colon or esophagus, or even to see the abnormal blood vessels that appear in the earliest stages of macular degeneration - a leading cause of blindness.

A technique exists for peeking into a live tissue several millimetres under the skin, revealing a landscape of cells, tissues and vessels. But that technique, called optical coherence tomography (OCT), isn't sensitive or specific enough to see the individual cells or the molecules that the cells are producing.

The new technique, tested in a living mouse, uses tiny particles called gold nanorods and sensitive algorithms to detect specific structures in three-dimensional images of living tissues.

It may allow doctors to monitor how an otherwise invisible tumour under the skin is responding to treatment, or to understand how individual cells break free from a tumour and travel to distant sites.​

London, March 20 (IANS) If an individual has the determination, nothing can stop her or him from achieving the goal, suggests a study.

The study, which showed that a sighted, adult brain is able to recruit when it is sufficiently challenged pointed out that learning a complex task over a long period can challenge the brain and break the barriers that were long thought to be fixed.

"We are all capable of re-tuning our brains if we're prepared to put the work in," said lead author Marcin Szwed from the Jagiellonian University in Poland.

The results revealed that we could supercharge the brain to be more flexible as the brain overcomes the normal division of labour and establishes new connections to boost its power.

"Our findings show that we can establish new connections if we undertake a complex enough task and are given long enough to learn it," Szwed maintained.

The findings, to be published in the journal eLife, could have implications for our power to bend different sections of the brain to our will by learning other demanding skills, such as playing a musical instrument or learning to drive.

Over a period of nine months, 29 volunteers were taught to read Braille while blindfolded.

They achieved reading speeds of up to 17 words per minute.

Before and after the course, they took part in a functional Magnetic Resonance Imaging (fMRI) experiment to test the impact of their learning on regions of the brain.

The findings call for a reassessment of our view of the functional organisation of the human brain, which is more flexible than the brains of other primates, the researchers asserted.​