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Scientists reconstruct detailed 3D eyes from single photo

New York, July 21 (IANS) A new 3D technique developed by Disney Research can capture the crucial yet subtle details of the eyes with just a single facial scan or even a single photo.

The method requires far less time and hardware than existing eye capture techniques because it employs a parametric model of the eye.

The model can reproduce the variations in the size and shape of the eyeball, the spots, craters and banding of the coloured iris and even the red veins of the white sclera.

"This new method of eye capture enables us to create highly realistic animations for films, games and medical applications and to do so with as little fuss as possible," said Markus Gross, vice president at Disney Research.

The model can be used to automatically duplicate the details of an actor's eyes and can be manipulated to accommodate a story line, such as changing the dilation of the pupils to match lighting conditions, or increasing the size of veins to make the eyes look fatigued.

"After decades of research, facial capture technology is now so advanced that it can be difficult to distinguish between digital faces and real ones," added Thabo Beeler, senior research scientist at Disney Research.

The parametric model is based in large part on a database of 30 eyes that were captured in high resolution using that exhaustive process.

The database provides details about the white sclera and the coloured iris, while a separate model was used to represent variations in the size and shape of the eyeball itself.

The research team will present the findings at the ACM International Conference on Computer Graphics & Interactive Techniques (SIGGRAPH) in California on July 24.​

People estimate own ability based on others' performance

London, July 21 (IANS) When it comes to rating one's own abilities, you are strongly influenced by the performance of others, a study has found.

Interaction with high performers makes one feel more capable of being cooperative in team settings but less competent in competitive situations, suggested the study published in the journal Neuron.

The research shows that comparisons with other people can be used as an effective means for self-evaluation and conversely people make judgments about others based on their own traits. 

"We found that although people estimated their abilities on the basis of their own performance in a rational manner, their estimates of themselves were partly merged with the performance of others," University of Oxford researcher Marco Wittmann said.

Moreover, the degree of "self-other-mergence" is associated with an activity in a brain region previously implicated in theory of mind -- the ability to understand the mental state of oneself and others.

Relatively little is known about which brain regions are involved in estimating the abilities of oneself and others, suggested the study.

However, the brain imaging data revealed that two distinct regions in the brains's frontal cortex tracked the estimated abilities of oneself and others.

According to the study, the researchers addressed this question by combining behavioural experiments with functional magnetic resonance imaging. 

Twenty-four subjects participated in two games that involved either assessing the colors of shapes or estimating elapsed time. 

The researchers also assessed how the subjects' expected performance ratings were influenced by cooperative and competitive contexts. 

In cooperative situations, the subjects evaluated themselves more positively when the other players performed well and more negatively when the other players performed poorly. 

However, in the competitive context, the subjects evaluated themselves more negatively when interacted with high performers compared to low performers, the study suggested.

"Our behavioural findings match well with what people experience in their workplace. They might feel better or worse about themselves depending on how well the group they are working with is doing, or they might feel worse about themselves when facing a strong competitor," added Wittman.​

Novel sunscreen compound to prevent UV-A radiation developed

London, July 21 (IANS) Researchers have developed a new compound that offers unprecedented protection to the skin against the harmful effects of ultraviolet-A (UV-A) radiation in sunlight.

Most sunscreens in the market protect the skin well against solar UV-B (shortwave) radiation but have limited effectiveness against damage induced by UV-A (long-wave), relying on the reflective properties of creams to defend against dangerous UV-A rays, which can cause photo-ageing -- premature ageing of the skin -- and cell damage as well as skin cancer.

The new compound, named by the team as "mitoiron claw", offers strong protection within our cells precisely where the greatest damage from UV-A occurs, and doesn't interfere with rest of the cell.

"Our mitochondria-targeted compound can address an unmet need in the skincare and sunscreen fields. This mitoiron claw is a highly effective compound, offering unprecedented protection against UVA-induced mitochondrial damage," said Charareh Pourzand from the University of Bath in Britain.

Free iron concentration is particularly high within mitochondria -- the powerhouse of the cell -- where it is needed for several vital functions. However, upon exposure to UV-A in sunlight, excess free iron acts as a catalyst for the production of toxic reactive oxygen species (ROS), damaging cell components such as DNA, fat and proteins thereby increasing the risk of cell death and cancer.

This custom-designed iron chelator -- a molecule that binds to an iron atom like a claw -- moves directly to mitochondria where it safely binds the excess free iron, preventing it from reacting upon exposure to UV-A rays, the researchers noted.

Tests with human skin fibroblast cells exposed to UV-A radiation equivalent to 140 minutes of uninterrupted sun exposure at sea level, showed that cells treated with the mitoiron claw were completely protected against cell death. 

However, the cells untreated with the mitoiron claw suffered significant cell death.

"The role of iron-mediated damage induced upon exposure of skin cells to UV-A has been underestimated for many years. For efficient protection against UVA-induced iron damage of skin strong chelators are needed, but until now these risked toxic effects caused by non-targeted iron starvation of cells," added Pourzand.

The researchers hope to see the mitoiron claw compound added to sunscreens and skin care products within 3-4 years.

The findings were published in the Journal of Investigative Dermatology.​

New imaging tool to help treat common brain disorders

New York, July 21 (IANS) Scientists have developed a new tool to scan the human brain for changes in synapses that are associated with common brain disorders.

A synapse is a junction between two nerve cells, consisting of a minute gap across which impulses pass.

The team from Yale University set out to develop a method for measuring the number of synapses, or synaptic density, in the living brain.

To quantify synapses throughout the brain, they combined Positron Emission Tomography (PET) scanning technology with biochemistry. 

A radioactive tracer was developed that, when injected into the body, binds with a key protein that is present in all synapses across the brain. 

The researchers used the imaging technique in both baboons and humans and confirmed that the new method did serve as a marker for synaptic density. 

It also revealed synaptic loss in three patients with epilepsy compared to healthy individuals.

"This is the first time we have synaptic density measurement in live human beings," said study senior author Richard Carson. 

"Up to now any measurement of synaptic density was post-mortem," he added in a paper published in the journal Science Translational Medicine.

The technique may provide insights into the diagnosis and treatment of a broad range of disorders, including epilepsy and Alzheimer's disease.​

Exercise as effective as surgery for knee injury

London, July 21 (IANS) Exercise therapy is as effective as surgery for middle-aged patients with a common type of knee injury known as meniscal tear, a study has revealed.

Meniscal tear is the damage to the rubbery discs that cushion the knee joint.

According to the study published in the journal The BMJ, the researchers suggested that supervised exercise therapy be considered a treatment option for middle-aged patients with this type of knee damage.

The research suggests that arthroscopic knee surgery offers little benefit for most patients.

The researchers carried out a randomised controlled trial for the study to compare exercise therapy with arthroscopic surgery among middle-aged patients with degenerative meniscal tears.

They identified 140 affected adults (average age 50 years), almost all of whom had no definitive x-ray evidence of osteoarthritis.

Half of the patients received a supervised exercise programme over 12 weeks (two-three sessions each week) and half received arthroscopic surgery followed by simple daily exercises to perform at home.

Thigh muscle strength was assessed at three months and knee function was recorded at two years.

No clinically relevant difference was found between the two groups for outcomes such as pain, function in sport and recreation, and knee-related quality of life. At three months, muscle strength had improved in the exercise group of patients.

No adverse events occurred in either group during the two-year follow-up. Of all participants in the exercise group, 13 crossed over to surgery during the follow-up period -- with no additional benefits.

"Supervised exercise therapy showed positive effects over surgery in improving thigh muscle strength, at least in short term. Our results should encourage clinicians and middle aged patients with degenerative meniscal tear and no radiographic evidence of osteoarthritis to consider supervised structured exercise therapy as a treatment option," University of Helsinki researcher Teppo Jarvinen said.​

Two Earth-like exoplanets may harbour life, shows Hubble data

Washington, July 21 (IANS) Using NASA's Hubble Space Telescope, a team of astronomers has conducted the first search for atmospheres around Earth-sized exoplanets beyond our solar system and found indications that increase the chances of presence of life on two rocky exoplanets.

The exoplanets TRAPPIST-1b and TRAPPIST-1c -- approximately 40 light years away -- are unlikely to have puffy, hydrogen-dominated atmospheres usually found on gaseous worlds.

"The lack of a smothering hydrogen-helium envelope increases the chances for habitability on these planets," said team member Nikole Lewis from Space Telescope Science Institute (STScI) in Baltimore. 

"If they had a significant hydrogen-helium envelope, there is no chance that either one of them could potentially support life because the dense atmosphere would act like a greenhouse," he added.

The planets orbit a red dwarf star at least 500 million years old, in the constellation of Aquarius.

TRAPPIST-1b completes a circuit around its red dwarf star in 1.5 days and TRAPPIST-1c in 2.4 days.

The planets are between 20 and 100 times closer to their star than the Earth is to the Sun.

Because their star is so much fainter than our sun, researchers think that at least one of the planets, TRAPPIST-1c, may be within the star's habitable zone, where moderate temperatures could allow for liquid water to pool.

Julien de Wit from the Massachusetts Institute of Technology led a team of scientists to observe the planets in near-infrared light using Hubble's Wide Field Camera 3.

They used spectroscopy to decode the light and reveal clues to the chemical makeup of an atmosphere.

"These initial Hubble observations are a promising first step in learning more about these nearby worlds, whether they could be rocky like the Earth, and whether they could sustain life," said Geoff Yoder, acting associate administrator for NASA's Science Mission Directorate in Washington.

"This is an exciting time for NASA and exoplanet research," he added.

The researchers hope to use Hubble to conduct follow-up observations to search for thinner atmospheres, composed of elements heavier than hydrogen, like those of the Earth and Venus.

"With more data, we could perhaps detect methane or see water features in the atmospheres, which would give us estimates of the depth of the atmospheres," noted Hannah Wakeford from NASA's Goddard Space Flight Centre in a paper appeared in the journal Nature.

Observations from future telescopes, including NASA's James Webb Space Telescope, will help determine the full composition of these atmospheres and hunt for potential bio-signatures.

Webb also will analyse a planet's temperature and surface pressure -- key factors in assessing its habitability.​

2016 on track to be world's hottest year on record: WMO

Geneva, July 22 (IANS) The World Meteorological Organisation (WMO) on Thursday warned global temperatures for the first six months of this year shattered more records, meaning 2016 is on track to be the world's hottest year on record.

WMO noted June marked the 14th consecutive month of record heat for land and oceans and the 378th consecutive month with temperatures above the 20th century average. The last month with temperatures below the 20th century average was December 1984, Xinhua reported.

"Another month, another record. And another. And another. Decades-long trends of climate change are reaching new climaxes, fuelled by the strong 2015-2016 El Nino," WMO Secretary-General Petteri Taalas was quoted as saying.

"The El Nino event, which turned up the Earth's thermostat, has now disappeared. Climate change, caused by heat-trapping greenhouse gases, will not. This means we face more heatwaves, more extreme rainfall and potential for higher impact tropical cyclones," Taalas added.

Meanwhile, carbon dioxide concentrations have passed the symbolic milestone of 400 parts per million (ppm) in the atmosphere so far this year. Carbon dioxide levels vary according to the season, but the underlying trend is upwards. They showed a surprising increase for the first half of 2016, rising in June 2016 to nearly 407 ppm, four ppm greater than in June 2015.

United Nations Secretary-General Ban Ki-moon has invited leaders to a special event on September 21 to deposit their instruments of ratification, acceptance, approval or accession to the Paris Agreement on climate change. 

It will also provide an opportunity for other countries to publicly commit to the agreement before the end of 2016.

Fluctuations in 'bad' cholesterol may lead to memory loss

London, July 20 (IANS) Greater fluctuations in "bad" cholesterol levels are likely to cause worse cognitive function like acute memory loss in elderly adults, says a research.

The findings showed that greater fluctuations in low-density lipoprotein cholesterol (LDL), or "bad" cholesterol can affect blood flow to the brain -- a process which could lead to memory loss and even Alzheimer's, according to American Heart Association. 

The study participants with the highest LDL cholesterol variability took 2.7 seconds longer on average to finish a cognitive test to name ink colours of colour words written in different ink (for example, the word blue written in red ink), compared to individuals with the lowest variability.

"While this might seem like a small effect, it is significant at a population level," said lead author Roelof Smit, doctoral student at Leiden University in the Netherlands.

The link between variability and declining cognitive function was found regardless of average bad cholesterol levels or use of cholesterol-lowering statin drugs.

In addition, greater fluctuations in bad cholesterol can lead to greater white matter hyper-intensity load -- which has been linked to dysfunctioning in endothelial cells that make up the inner lining of blood vessels, and can further lead to a cardiovascular disease.

LDL cholesterol variability may also be important to neurocognitive function, said the paper published in the journal Circulation.

"These results add an important puzzle piece to the emerging evidence that heart risk factors are closely related to brain health," Smit added.

Measurements fluctuate because of diet, exercise, frequency of cholesterol-lowering statins and other factors.

However, these fluctuations might also reflect an increasingly impaired homeostasis -- the balance between food intake and energy expenditure -- for example, due to age or underlying disease, added J. Wouter Jukema, Professor at the Leiden University.

For the study, the team involved 4,428 elderly participants from Scotland, Ireland and the Netherlands. The participants either had pre-existing heart disease or were at a higher risk for developing the condition because of histories of hypertension, cigarette smoking or diabetes.

They examined associations between LDL cholesterol variability and four cognitive measures: colour-word test for selective attention, letter-digit coding to assess information processing speed and picture-word learning to test verbal memory in two ways -- immediate recall and delayed recall after 20 minutes.​

Light-based wireless communications a reality soon: Facebook team

New York, July 20 (IANS) Researchers from Facebook's Connectivity Lab have developed a new technology that can one day make light-based wireless communications -- a far superior technology than the ones based on radio frequencies or microwaves -- a reality in the future.

The new technology can pave the way for fast optical wireless networks capable of delivering internet service to far-flung places.

"A large fraction of people don't connect to the internet because the wireless communications infrastructure is not available where they live, mostly in very rural areas of the world," said Tobias Tiecke, who led the research team. 

Light-based wireless communication, also called free-space optical communications, offers a promising way to bring the internet to areas where optical fibres and cell towers can be challenging to deploy in a cost-effective way. 

Using laser light to carry information across the atmosphere can potentially offer very high bandwidths and data capacity, but one of the primary challenges has been how to precisely point a very small laser beam carrying the data at a tiny light detector that is some distance away.

The Facebook researchers used fluorescent materials instead of traditional optics to collect light and concentrated it onto a small photodetector. 

They combined this light collector, which featured 126 sq cm of surface that can collect light from any direction, with existing telecommunications technology to achieve data rates of more than 2 gigabits-per-second (Gbps).

"We demonstrated the use of fluorescent optical fibres that absorb one colour of light and emit another colour," Tiecke said. 

"The optical fibres absorb light coming from any direction over a large area, and the emitted light travels inside the optical fibre, which funnels the light to a small, very fast photodetector," he added in a paper described in the journal Optica.

The new light collector uses plastic optical fibres containing organic dye molecules that absorb blue light and emit green light. 

This setup replaces the classical optics and motion platform typically required to point the light to the collection area.

The fast speeds are possible because less than two nanoseconds lapse between the blue light absorption and the green light emission. 

In addition, by incorporating a signal modulation method called orthogonal frequency division multiplexing, or OFDM, the researchers transmitted more than 2 Gbps despite the system's bandwidth of 100 MHz.

Reading fiction may encourage empathy

Toronto, July 20 (IANS) Reading fiction might be good for your mental health but exploring inner lives of characters like Jane Eyre or Anna Karenina can form ideas about others' emotions, motives and ideas, suggested a study.

According to the study published in journal Trends in Cognitive Sciences, a psychologist-novelist shows that reading or watching narratives may encourage empathy. 

"This intersection between literature and psychology has only taken off in the last few years. In part, because researchers are recognising that there is something important about imagination," said Keith Oatley, Professor, the University of Toronto Department.

Reading fiction and perhaps especially literary fiction simulates a kind of social world, prompting understanding and empathy in the reader, revealed the study. 

According to the research, people were asked to imagine phrases like "a dark blue carpet" and "an orange striped pencil" while staying in an functional magnetic resonance imaging (fMRI) machine. 

Three such phrases were enough activate the hippocampus -- brain region associated with learning and memory, suggested the study.

"This points to the power of the reader's own mind, writers don't need to describe scenarios exhaustively to draw out the reader's imagination -- they only need to suggest a scene," added Oatley. 

To measure this empathetic response the researchers were the first to use the "Mind of the Eyes Test", in which participants view 36 photographs of people's eyes and for each choose among four terms to indicate what the person is thinking or feeling. 

The researchers found that reading narrative fiction gave rise to significantly higher scores than it did while reading non-fictional books.

Similar empathy-boosting effects have been found when participants watched the fictional television drama - The West Wing or played a video game with a narrative storyline, suggested the study.

Further studies have shown that narratives can even generate empathy for a race or culture that is dissimilar to one's own.