Knowledge Update

​Tokyo, June 9 (IANS) Japan's Toyota Motor is planning to introduce a telecommute system, which will allow around 25,000 employees to do most of their work from home, to improve work-life balance, the company announced Thursday.

​London, June 9 (IANS) Most of the commonly prescribed antidepressant drugs are ineffective and some may be unsafe for children and teenagers with major depression, according to a study.

"The balance of risks and benefits of antidepressants for the treatment of major depression does not seem to offer a clear advantage in children and teenagers, with probably only the exception of fluoxetine," said co-author Peng Xie from the Chongqing Medical University in China. 

Major depressive disorder is common in children and adolescents across the world, affecting around 3 per cent of children aged 6 to 12 years and about 6 per cent of teenagers aged 13 to 18 years.

"Without access to individual-level data it is difficult to get accurate effect estimates and we can't be completely confident about the accuracy of the information contained in published and unpublished trials," said study lead author Andrea Cipriani from the University of Oxford. 

Cipriani and colleagues did a systematic review and network meta-analysis of all published and unpublished randomised trials comparing the effects of 14 antidepressants in young people with major depression up to the end of May 2015, according to the study published in the journal The Lancet.

Analysis of 34 trials involving 5,260 participants (average age 9 to 18 years) showed that the benefits outweighed the risks in terms of efficacy and tolerability only for fluoxetine.

Nortriptyline was less efficacious than seven other antidepressants and placebo.

Imipramine, venlafaxine, and duloxetine had the worst profile of tolerability, leading to significantly more discontinuation than placebo. Venlafaxine was linked with an increased risk of engaging in suicidal thoughts or attempts compared with placebo and five other antidepressants. 

The researchers warned that due to the lack of reliable data, it was not possible to comprehensively assess the risk of suicidality for all drugs.

"Hundreds of thousands of people worldwide have agreed to participate in trials aiming to find better treatments for their disorders and, ultimately, help the progress of medical science," Cipriani said.

"Patients' privacy must be guaranteed by adequate policies and technological measures, but delay in implementing responsible data sharing policies has negative consequences for medical research and patient outcomes, as demonstrated by this study," he added.​

​Toronto, June 9 (IANS) A team of researchers at a Canadian university has developed an advanced 4-D technique to avoid costly delays often associated with massive public infrastructure projects.

"Any delay in the work on one segment might impact the work on another, which ultimately results in delaying the whole project and augmenting the cost," said senior study author Amin Hammad of Concordia University in Montreal. 

"The simulation methods we've developed help contractors analyse the schedule and eliminate the risks," Hammad added.

The study was recently published in the journal Automation in Construction. 

Reconstructing heavily used highways is an extremely complex process because of the need to maintain traffic flow. Therefore, a plan is usually required to gradually shift the traffic from the existing segments to the newly built ones.

The parallel coordination of construction and demolition activities with traffic flow is essential to the success of projects, according to Hammad. 

"That's why our new modelling method uses a 4-D approach -- taking into account the three normal space axes, plus time, to coordinate the traffic phasing with the demolition and construction of the old and new segments, respectively," he said.

This method is the first to integrate stochastic simulation techniques -- algorithms to predict randomness -- with 3-D modelling of highways to generate 4-D representations that can be used to detect and plan for scheduling clashes, and define the feasible sequences in which the segments of the highway bridges can be constructed or demolished.​

​Sydney, June 9 (IANS) The move from life on land to life in the sea has led to the evolution of a new sense for sea snakes, potentially making them more likely to be able to sense vibrations from all directions, an Australian study suggests.

The international team studied tiny and poorly understood structures on the heads of snakes called 'scale sensilla'. 

"Land snakes and many lizards have small raised structures on the scales on their heads -- called scale sensilla -- that they use to sense objects by direct touch," said lead author Jenna Crowe-Riddell from the University of Adelaide in Australia.

"We found that the scale sensilla of sea snakes were much more dome-shaped than the sensilla of land snakes, with the organs protruded further from the animals' scales, potentially making them more likely to be able to sense vibrations from all directions,” Crowe-Riddell noted.

The researchers also found that scale sensilla on some of the fully aquatic snakes covered a much higher proportion of the scales' surface.

"We believe sea snakes use these organs to sense objects at a distance by 'feeling' movements in the water. This hydrodynamic sense is not an option for land animals. In water, a new way of sensing the environment becomes possible," Crowe-Riddell noted.

The researchers looked at 19 species of snakes, including fully-aquatic, semi-aquatic and land species, and measured the coverage of sensilla over single scales on their heads.

They used DNA sequencing to reconstruct the evolutionary relationships between the snakes, and used microscope imaging and specially developed software to automatically detect the small organs from silicone casts of snake heads. They also examined the shape of the sensilla using scanning electron microscopy.

The research was published in the Royal Society journal Open Biology.​

​London, June 9 (IANS) Confirming a long-standing hypothesis, scientists from the Netherlands' Leiden University have shown that the genetic information in the DNA not only determines who we are, but also the DNA mechanics.

Since the mid-198080s it has been hypothesised that there is a second layer of information on top of the genetic code: DNA’s mechanical properties. 

Each of our cells contains two meters of DNA molecules, so these molecules need to be wrapped up tightly to fit inside a single cell. 

The way in which DNA is folded, determines how the letters are read out, and therefore which proteins are actually made. 

In each organ, only relevant parts of the genetic information are read, based on how the DNA is folded. 

The theory goes that mechanical cues within the DNA structures determine how DNA prefers to fold.

In a study published in the journal PLoS One, Leiden physicist Helmut Schiessel and his research group provided strong evidence that this second layer of information indeed exists. 

With their computer code they simulated the folding of DNA strands with randomly assigned mechanical cues. 

It turns out that these cues indeed determine how the DNA molecule is folded into so-called nucleosomes. 

Schiessel found correlations between the mechanics and the actual folding structure in the genome of two organisms ? baker’s yeast and fission yeast. 

With this finding we know that evolutionary changes in DNA ? mutations ? can have two very different effects.

The letter sequence encoding for a specific protein can change or the mechanics of the DNA structure can change, resulting in a different packaging and accessibility of the DNA and therefore a different frequency of production of that protein.​

​New York, June 9 (IANS) Researchers have prepared the first spatially explicit data set of the location and size of urban settlements globally over the past 6,000 years -- offering fresh clarity as to how the growth of cities transforms humans into an "urban species".

The researchers from the Yale School of Forestry and Environmental Studies created maps through digitising, transcribing, and geocoding a deep trove of historical, archaeological, and census-based urban population data previously available only in tabular form. 

The study, published recently in the journal Scientific Data, has made it possible to access information on urban centres from 3700 B.C. to A.D. 2000.

"To better understand urbanisation today it is helpful to know what urbanisation looked like through history," said lead author Meredith Reba.

"By understanding how cities have grown and changed over time, throughout history, it might tell us something useful about how they are changing today," she added.

The findings have broad applications. The dataset offers an important first step toward understanding the geographic distribution of urban populations throughout history and across the world.

Currently the only spatially explicit data available at a global scale is the United Nations World Urbanisation Prospects, which provides population values, latitudes, and longitudes for places with populations of 300,000 or more. However, it goes back only to 1950.

The new study allows researchers to map and visualise city level population changes through time. For example, Istanbul in Turkey underwent a major period of population decline between AD 1057 and AD 1453. During this time the population dropped from approximately 300,000 to 45,000 due to a series of events including a city sacking by the Crusaders and a bout with the plague.

According to the researchers, the ability to pinpoint the size and location of human populations over time will help researchers understand the evolving characteristics of the human species -- particularly human interactions with the environment.​

​Toronto, June 9 (IANS) Lignin, a natural material in plants and a major waste product of the paper industry, can be added to sunscreen creams to protect you from getting sunburn, says a new study.

Most sunscreen products currently in the market contain synthetic compounds that help prevent ultraviolet rays from damaging skin. But consumers are searching for better product performance that comes from natural sources. This has led scientists to experiment with compounds from a variety of sources. 

According to the study published recently in the journal Sustainable Chemistry and Engineering, Shiping Zhu from Canada's McMaster University and Qiu Xueqing of South China University of Technology found that out of five types of lignin tested, organosolv lignin improved the sun protection factor (SPF) of sunblock the most. 

Sunscreen containing just one percent of this compound doubled the lotion's original SPF -- it went from 15 to 30. 

A lotion with 10 percent organosolv lignin increased SPF even further, from 15 to almost 92, but excessive amounts of hydrophilic lignin such as lignosulfonate caused the product to start separating. 

The researchers said that although more work is needed to be done, the results represent a promising first step toward the development of lignin-containing sunscreen.

​London, June 10 (IANS) Deficiency of zinc can adversely impact the essential metabolic functions of most living organisms, finds a new study suggesting that even moderate levels of deficiency of the trace element can be bad for digestion.

The findings showed that zinc deficiency in an animal's diet impedes pancreatic digestive activity and results in significant digestive impairment, even at an early stage. 

In humans, it has been known to increase the levels of inflammation markers and reduce immunocompetence -- the ability of the body to produce a normal immune response following exposure to an antigen.

As zinc only exists in small amounts in an organism, it has to be consumed by way of nutrition, the researchers said. 

The beginning of zinc depletion usually goes unnoticed and without any visible symptoms, but minute changes can be identified in the liver and in the blood. 

Pancreas, known as the control centre for food digestion and energy homeostasis in the body, pumps zinc into the gastrointestinal tract in order to maintain a consistent zinc level. 

Conversely, if an organism is depleted of zinc, it reduces its pancreatic zinc excretion to a minimum. 

"The accumulation of undigested food inside the gastrointestinal tract due to zinc deficiency results in feeling less hungry," said lead author Daniel Brugger of the Chair of Animal Nutrition at Technical University of Munich (TUM) in Germany.

"We proved that there is a direct correlation between the amount of digestive enzymes inside the pancreas and zinc levels in the organism as a whole," Brugger added in the paper published in the British Journal of Nutrition.

For the purpose of this study, the team fed piglets that had just been weaned on a diet containing different amounts of zinc to develop early-stage zinc deficiency. 

On the one hand, it was observed that the body tried to absorb zinc more efficiently, while on the other it reduced pancreatic zinc excretion. 

"Even short intervals of zinc deficiency in the diet should be avoided," Brugger said, adding that particularly older adults need to monitor their zinc intake with foods that are high in zinc like seafood, spinach, pumpkin nuts, cocoa, chocolate and mushrooms.​

​Wellington, June 10 (IANS) Air pollution, including environmental and household air pollution, has emerged as the leading risk factor for stroke globally, finds a new study.

The findings showed that about a third (29.2 per cent) of global disability associated with stroke such as loss of vision and/or speech, paralysis and confusion, is linked to air pollution (including environmental air pollution and household air pollution). 

This is especially high in developing countries -- 33.7 per cent vs 10.2 per cent in developed countries, the researchers said.

From 1990 to 2013, stroke associated with environmental air pollution showed an increase by over 33 per cent worldwide. However, second-hand smoke saw a decrease by 31 per cent between the same period. 

"A striking finding of our study is the unexpectedly high proportion of stroke burden attributable to environmental air pollution, especially in developing countries," said lead author Valery L Feigin, Professor at Auckland University of Technology in New Zealand. 

Also, over 90 per cent of the global burden of stroke was caused by modifiable risk factors and 74 per cent of them are behavioural risk factors such as smoking, poor diet and low physical activity. 

"Controlling these risk factors could prevent about three-quarters of strokes worldwide," Feigin added.

Further, air pollution, environmental risks, tobacco smoke, high blood pressure and dietary risks were the other risk factors found for stroke in developing countries compared to developed countries.

Household air pollution was found to be an important risk factor for stroke in central, eastern and western sub-Saharan Africa as well as south Asia.

Every year, approximately 15 million people worldwide suffer a stroke. High blood pressure, diet low in fruit, high body mass index (BMI), diet high in sodium, smoking, diet low in vegetables, environmental air pollution, household pollution from solid fuels, diet low in whole grains and high blood sugar were found as the ten major risk factors for stroke. 

"Our findings are important for helping national governments and international agencies to develop and prioritise public health programmes and policies," Feigin noted.

For the study, published in The Lancet Neurology journal, the team used data from the Global Burden of Disease Study to estimate the disease burden of stroke associated with 17 risk factors in 188 countries between 1990-2013. 

"Air pollution is not just a problem in big cities, but is also a global problem. It is one aspect of the fossil fuel and global warming problem, which is itself partly a result of westernisation and urbanisation, especially in India and China," the researchers concluded.​

​Wellington, June 10 (IANS) Air pollution, including environmental and household air pollution, has emerged as the leading risk factor for stroke globally, finds a new study.

The findings showed that about a third (29.2 per cent) of global disability associated with stroke such as loss of vision and/or speech, paralysis and confusion, is linked to air pollution (including environmental air pollution and household air pollution). 

This is especially high in developing countries -- 33.7 per cent vs 10.2 per cent in developed countries, the researchers said.

From 1990 to 2013, stroke associated with environmental air pollution showed an increase by over 33 per cent worldwide. However, second-hand smoke saw a decrease by 31 per cent between the same period. 

"A striking finding of our study is the unexpectedly high proportion of stroke burden attributable to environmental air pollution, especially in developing countries," said lead author Valery L Feigin, Professor at Auckland University of Technology in New Zealand. 

Also, over 90 per cent of the global burden of stroke was caused by modifiable risk factors and 74 per cent of them are behavioural risk factors such as smoking, poor diet and low physical activity. 

"Controlling these risk factors could prevent about three-quarters of strokes worldwide," Feigin added.

Further, air pollution, environmental risks, tobacco smoke, high blood pressure and dietary risks were the other risk factors found for stroke in developing countries compared to developed countries.

Household air pollution was found to be an important risk factor for stroke in central, eastern and western sub-Saharan Africa as well as south Asia.

Every year, approximately 15 million people worldwide suffer a stroke. High blood pressure, diet low in fruit, high body mass index (BMI), diet high in sodium, smoking, diet low in vegetables, environmental air pollution, household pollution from solid fuels, diet low in whole grains and high blood sugar were found as the ten major risk factors for stroke. 

"Our findings are important for helping national governments and international agencies to develop and prioritise public health programmes and policies," Feigin noted.

For the study, published in The Lancet Neurology journal, the team used data from the Global Burden of Disease Study to estimate the disease burden of stroke associated with 17 risk factors in 188 countries between 1990-2013. 

"Air pollution is not just a problem in big cities, but is also a global problem. It is one aspect of the fossil fuel and global warming problem, which is itself partly a result of westernisation and urbanisation, especially in India and China," the researchers concluded.​