Knowledge Update

New York, Sep 9 (IANS) Researchers have identified a set of 30 inherited recessive genes that play a role in intellectual disability, a neurodevelopmental disorder.

The new findings, published in the online journal Molecular Psychiatry, could be applied to DNA screenings in determining the possibility of a couple producing a child with intellectual disability.

"The implications are enormous," said principal investigator Saima Riazuddin, Professor at University of Maryland School of Medicine in the US. 

"The next phase of our study is to come up with therapeutic options and personalised protocols that could help patients improve their intellectual function," Riazuddin said.

Intellectual disability, or ID (previously known as mental retardation), becomes apparent in children before the age of 18 and affects, according to the US Centers for Disease Control and Prevention (CDC), as many as 213 million people around the world.

The disorder, which is measured by an intelligence quotient below 70, significantly limits an individual's intellectual ability and practical skills. 

The new study presents the outcomes of a five-year investigation that was conducted over three continents.

In order to identify potential genetic causes for intellectual disability, investigators assembled a test group of 121 families in rural Pakistan, in which there was a higher incidence of the disorder and consanguineous marriages (marriages between blood relations). 

More than 15,000 DNA samples were collected, which were analysed both in the Netherlands and at University of Maryland School of Medicine's Institute of Genomic Sciences (IGS), using next-generation genetic sequencing.

From an initial pool of 2,000 possible genes, the study, categorised 30 novel candidate genes possessing a strong potential for causing ID -- and possibly other brain disorders as well. 

London, Sep 9 (IANS) Children with emotional parents are more likely to be successful, a study has found.

The research found that a caring and emotionally attentive environment is liable to be a long-term game-changer.

"The findings support developmental theories which propose that a high emotional quality in the mother-child interaction (attachment security) fosters the cognitive development of the child," said Schneider-Hassloff, researcher at University of Ulm, in Germany.

Looking at 27 children aged between four and six, the study examined the quality of the emotional bond to their parents and their cognitive control including resisting temptation, their ability to remember things and whether they are shy or withdrawn.

First, the researchers looked at the quality of the emotional bond -- referred to as emotional availability (EA) -- between mothers and children. 

Second, the children's executive functions were measured through a number of exercises.

Finally, the study measured the neural responses of children who were tasked to inhibit certain aspects of their behaviour. This was achieved through EEG (Electroencephalography) by measuring small variations in voltage in certain key parts of the brain.

Parents who encourage independence in their kids while remaining emotionally available, give their young ones a better chance at future success.

"This study investigated the association between emotional interaction quality and the electrophysiological correlates of executive functions in preschool children for the first time thereby shedding new light on the long-term importance of emotional nurturing," Hassloff added in the study, published in the journal Frontiers in Human Neuroscience.

Even in hardship, parents can create an emotional space that will have long-lasting and powerful consequences for the child's future life-skills, the study suggested.

​Toronto, Sep 9 (IANS) An estimated 3.3 million square kilometres -- almost 10 per cent -- of wilderness area has been lost over the last 20 years, finds a study that shows catastrophic declines in wilderness areas around the world.

The alarming losses comprise a tenth of global wilderness since the 1990s -- an area twice the size of Alaska and half the size of the Amazon basin. 

The losses have occurred primarily in South America, which has experienced a 30 per cent decline in wilderness, and Africa, which has experienced a 14 per cent loss, the study said.

"The amount of wilderness loss in just two decades is staggering," Oscar Venter from the University of Northern British Colombia in Canada. 

"If we don't act soon, there will only be tiny remnants of wilderness around the planet, and this is a disaster for conservation, for climate change, and for some of the most vulnerable human communities on the planet," added James Watson from the University of Queensland in Australia. 

For the study, the researchers mapped wilderness areas around the globe, with "wilderness" being defined as biologically and ecologically intact landscapes free of any significant human disturbance. 

The findings underscore an immediate need for international policies to recognise the value of wilderness areas and to address the unprecedented threats they face, the researchers noted.

"We need to recognise that wilderness areas, which were considered to be de-facto protected due to their remoteness, is actually being dramatically lost around the world," Venter said.

"Without proactive global interventions we could lose the last jewels in nature's crown. You cannot restore wilderness, once it is gone, and the ecological process that underpin these ecosystems are gone, and it never comes back to the state it was. The only option is to proactively protect what is left," Venter noted.

The United Nations and other international policy mechanisms have ignored globally significant wilderness areas in key multilateral environmental agreements and this must change, th

​London, Sep 10 (IANS) Playing video games for a limited amount of time each week may increase cognitive abilities in children, a finding has suggested.

"Video gaming is neither good nor bad, but its level of use makes it so," said Jesus Pujol, doctor at the Hospital del Mar in Spain.

He and his colleagues investigated the relationship between weekly video game use and certain cognitive abilities and conduct-related problems.

In their study, published in the journal Annals of Neurology, 2,442 children aged between 7 to 11 years were studied and found that playing video games for one hour per week was associated with better motor skills and higher school achievement scores.

The team also found that weekly time spent gaming was steadily linked with conduct problems, peer conflicts, and reduced social abilities, with such negative effects being especially prominent in children who played nine or more hours of video games each week.

When the investigators looked at magnetic resonance imaging scans of the brains of a subgroup of children, they noted that gaming was linked with changes in basal ganglia white matter and functional connectivity in brain.

"Gaming use was associated with better function in brain circuits critical for learning based on the acquisition of new skills through practice," Pujol explained. 

Children traditionally acquire motor skills through action, for instance in relation to sports and outdoor games. Neuroimaging research suggested that training with desktop virtual environments is also capable of modulating brain systems that support motor skill learning

​Johannesburg, Sep 10 (IANS) Researchers have developed a new heart valve replacement device that does not require advanced cardiac surgical facilities or sophisticated cardiovascular imaging and offers hope for the thousands of patients suffering from rheumatic heart disease.

Rheumatic heart disease is caused by rheumatic fever, which results from a streptococcal infection. Patients develop fibrosis of the heart valves, leading to valvular heart disease, heart failure and death. 

"Over the past decade heart valve surgery has been revolutionised by transcatheter aortic valve implantation (TAVI), where heart valves are replaced or repaired via a catheter, obviating the need for open heart surgery or a heart-lung machine," said lead author Jacques Scherman, Cardiac Surgeon at the University of Cape Town, South Africa. 

The team developed a novel TAVI device which is "non-occlusive", meaning that there is no need to stop blood circulating to the body with rapid ventricular pacing -- quick heart beats. 

The device is also "self-locating" and does not require sophisticated cardiac imaging for positioning.

Testing the device in a sheep model, the team found that the device was easy to use and positioned the valve correctly, and the procedure could be performed without rapid ventricular pacing.

"We showed that this new non-occlusive, self-locating TAVI delivery system made it easy to perform transcatheter aortic valve replacement," Scherman said. 

"Using tactile feedback the device is stabilised in the correct position within the aortic root during the implantation. It also has a temporary backflow valve to prevent blood leaking backwards into the ventricle during the implantation of the new valve," Scherman explained.

All these factors together allowed for a slow, controlled implantation compared to the currently available balloon expandable devices. 

Further, this simplified approach to transcatheter aortic valve replacement could be done in hospitals without cardiac surgery at a fraction of the cost of conventional TAVI. 

It has the potential to save the lives of the large numbers of rheumatic heart disease patients in need of valve replacement, the researchers said.

The findings were presented at the SA Heart Congress 2016, in Cape Town recently.

​London, Sep 8 (IANS) An international team of researchers has found that a stellar system classified as a globular cluster for the 40-odd years since its detection actually has properties uncommon for a globular cluster that make it the ideal candidate for a living fossil from the early days of the Milky Way.

The cluster, known as Terzan 5 -- 19,000 light-years from Earth -- harbours stars of hugely different ages -- an age-gap of roughly seven billion years -- and bridges the gap in understanding between our galaxy's past and its present, the study said.

"Such galactic fossils allow astronomers to reconstruct an important piece of the history of our Milky Way," explained lead author of the study Francesco Ferraro from University of Bologna in Italy.

While the properties of Terzan 5 are uncommon for a globular cluster, they are very similar to the stellar population which can be found in the galactic bulge, the tightly packed central region of the Milky Way. 

These similarities could make Terzan 5 a fossilised relic of galaxy formation, representing one of the earliest building blocks of the Milky Way.

"Terzan 5 could represent an intriguing link between the local and the distant Universe, a surviving witness of the Galactic bulge assembly process," Ferraro said.

The team scoured data from the Advanced Camera for Surveys and the Wide Field Camera 3 on board Hubble, as well as from a suite of other ground-based telescopes. 

They found compelling evidence that there are two distinct kinds of stars in Terzan 5 which not only differ in the elements they contain, but have an age-gap of roughly seven billion years.

The ages of the two populations indicate that the star formation process in Terzan 5 was not continuous, but was dominated by two distinct bursts of star formation. 

"This requires the Terzan 5 ancestor to have large amounts of gas for a second generation of stars and to be quite massive. At least 100 million times the mass of the Sun," co-author of the study Davide Massari from National Institute for Astrophysics (INAF) , Italy.

Its unusual properties make Terzan 5 the ideal candidate for a living fossil from the early days of the Milky Way, said the study published in the Astrophysical Journal.

Somehow Terzan 5 has managed to survive being disrupted for billions of years, and has been preserved as a remnant of the distant past of the Milky Way.

The researchers believe that this discovery paves the way for a better and more complete understanding of galaxy assembly. 

New York, Sep 8 (IANS) Activities like playing video games or tennis may help enhance your memory, a study has found.

Attention-grabbing experiences release memory-enhancing chemicals in brain, helping to store memories that occur just before or soon after the experience, the study mentioned.

"Activation of the locus coeruleus (part of the brainstem) increases our memory of events that happen at the time of activation and may also increase the recall of those memories at a later time," said Robert Greene, Professor at the Peter O'Donnell Jr. Brain Institute at UT Southwestern Medical Center's Texas Institute for Brain Injury and Repair, at Dallas in Texas.

The study, published in the journal Nature explains at the molecular level why people tend to remember certain events in their lives with particular clarity as well as unrelated details surrounding those events.

The latest study established that dopamine in the brain can be naturally activated through behavioural actions and that these actions enhance memory retention.

The study tested 120 mice to establish a link between locus coeruleus (LC) neurons and neuronal circuits of the hippocampus -- the region of the brain responsible for recording memories -- that receive dopamine from the LC.

One part of the research involved putting the mice in an arena to search for food hidden in sand that changed location each day. 

The study found that the mice that were given a chance to explore an unfamiliar floor surface 30 minutes after being trained to remember the food location did better in remembering where to find the food the next day.

Researchers correlated this memory enhancement to a molecular process in the brain by injecting the mice with a genetically encoded light-sensitive activator called channelrhodopsin. 

This sensor allowed them to selectively activate dopamine-carrying neurons of the locus coeruleus that go to the hippocampus and to see first-hand which neurons were responsible for the memory enhancement.

They found that selectively activating the channelrhodopsin-labeled neurons with blue light (a technique called optogenetics) could substitute for the novelty experience as a memory enhancer in mice. 

They also found that this activation could cause a direct, long-lasting synaptic strengthening -- an enhancement of memory-relevant communication occurring at the junctions between neurons in the hippocampus. This process can mediate improvement of learning and memory.

"Some next steps include investigating how big an impact this finding can have on human learning, whether it can eventually lead to an understanding of how patients can develop failing memories, and how to better target effective therapies for these patients," Greene added.

New York, Sep 8 (IANS) Risk of death from sudden loss of heart function is significantly greater in patients with high thyroid hormone levels, according to a study.

"Our results indicate that thyroid hormone levels may be useful for assessing risk to prevent sudden cardiac death," said Layal Chaker, researcher at the Erasmus University Medical Center, at Rotterdam in the Netherland, in the study, published in the journal Circulation.

Although the link between abnormal levels of thyroid hormone and cardiovascular disease is well established, the hormone's relationship with sudden cardiac death is unclear.

Researchers analysed 10,318 patients with an average age of 65 and more than half were women for the study and linked the association of thyroid-stimulating hormone and free thyroxine thyroid hormone levels in blood samples with sudden cardiac deaths listed on medical records and death certificates.

They found that participants with free thyroxine hormone levels at the high end of the normal range were 2.5 times more likely to die of sudden cardiac death, compared to patients with levels at the lower end.

The ten-year risk of sudden cardiac death was four times greater among patients with higher free thyroxine levels compared to those with lower levels.

The increased risk persisted even after controlling for other risk factors such as high cholesterol and high blood pressure.

"The study suggests more caution is warranted in the treatment of thyroid hormone replacement. Replacement therapy is often aimed at the high normal range which carries a risk of over-treatment," Chaker added. 

​London, Sep 7 (IANS) Aimed at making the task of predicting renewable output easier for the industry, researchers have created an interactive web tool to estimate the quantum of energy that could be generated by wind or solar farms at any location.

The researchers have already used the tool, called Renewables.ninja, to estimate current Europe-wide solar and wind output.

"Renewables.ninja has already allowed us to answer important questions about the current and future renewable energy infrastructure across Europe and in the UK, and we hope others will use it to further examine the opportunities and challenges for renewables in the future," said Stefan Pfenninger from ETH Zurich in Switzerland.

To test the model, Pfenninger and Iain Staffell from College London used the tool to estimate the productivity of all wind farms planned or under construction in Europe for the next 20 years. 

Wind and solar energies have a strong dependence on weather conditions, and these can be difficult to integrate into national power systems that requires consistency. If there is excess power generated by all energy sources, then some supplies have to be turned off.

Currently, wind and solar power generators are the easiest to switch on and off, so they are often the first to go, meaning the power they generate can be wasted.

Renewables.ninja uses 30 years of observed and modelled weather data from organisations such as NASA to predict the wind speed likely to influence turbines and the sunlight likely to strike solar panels at any point on the Earth during the year, the researchers said in a paper published in the journal Energy.

These figures are combined with manufacturer's specifications for wind turbines and solar panels to give an estimate of the power output that could be generated by a farm placed at any location.

​Johannesburg, Sep 7 (IANS) Scientists, including researchers from India, have predicted the existence of a new boson that might aid in the understanding of dark matter in the universe.

Using data from a series of experiments that led to the discovery of Higgs boson at the European Organisation for Nuclear Research (CERN) in 2012, the team led by the High Energy Physics Group (HEP) of the University of Witwatersrand in Johannesburg established what they call "Madala boson".

The experiment was repeated in 2015 and 2016, after a two-and-half years' shut-down of the Large Hadron Collider (LHC) at CERN.

The data reported by the LHC experiments in 2016 have corroborated the features in the data that triggered the Madala hypothesis in the first place.

The Wits Madala project team consists of approximately 35 young South African and African students and researchers, along with theorists such as Professor Alan Cornell and Dr Mukesh Kumar.

Some of these scientists include Dr Deepak Kar and Dr Xifeng Ruan, two new academic staff in the group, who have years of expertise at the LHC.

"Based on a number of features and peculiarities of the data reported by the experiments at the LHC and collected up to the end of 2012, the Wits HEP group in collaboration with scientists in India and Sweden formulated the Madala hypothesis," says Professor Bruce Mellado, team leader of the HEP group at Wits, in a statement.

The hypothesis describes the existence of a new boson and field, similar to the Higgs boson.

Boson is a subatomic particle, such as a photon, which has zero or integral spin and follows the statistical description given by theoretical physicists Satyendra Nath Bose and Albert Einstein.

However, where the Higgs boson in the Standard Model of Physics only interacts with known matter, the Madala boson interacts with dark matter, which makes about 27 per cent of the universe.

The theory that underpins the understanding of fundamental interactions in nature in modern physics is referred to as the Standard Model of Physics.

With the discovery of the Higgs boson at the LHC in 2012, for which the Nobel Prize in Physics was awarded in 2013, the Standard Model of Physics is now complete.

However, this model is insufficient to describe a number of phenomena such as dark matter.

"With the Madala hypothesis predictions of striking signatures are made, that is being pursued by the young scientists of the Wits HEP group," the authors noted.