Knowledge Update

​New York, Sep 9 (IANS) The role of genes in congenital heart defects is more complex than previously thought with new research finding that the overall risk is determined by a combination of gene effects on both inside and outside of the heart itself.

Congenital heart defect (CHD) is a problem in the structure of the heart that is present at birth and are a leading cause of birth defect-related deaths. 

Normal heart formation depends on interactions of multiple types of cells that collaborate in precise times and places throughout development to build the heart's intricate structures. 

To figure out how these interactions can go awry, researchers at the University of California, at Irvine, in the US, studied atrial septal defects (ASDs, a common type of heart defect) in a mouse model.

They studied the developmental disorder Cornelia de Lange Syndrome (CdLS) -- a very rare genetic disorder present from birth, but not always diagnosed at birth. 

Most cases of Cornelia de Lange Syndrome are caused by mutations that inactivate a single copy of Nipbl -- a gene that directs the expression of many hundreds of other genes in tissues throughout the body. 

Just as people with Cornelia de Lange Syndrome have a high incidence of heart defects, 30 per cent of mice that harbour similar Nipbl mutations exhibit atrial septal defects, the researchers said.

Using genetically modified mouse models, they then selectively introduced or removed Nipbl mutations in different tissues during embryonic development. 

The findings showed that no Nipbl deficiency in any single tissue -- including the tissue that forms the heart itself -- could single-handedly account for the development of atrial septal defects. 

Rather, the development of heart defects was determined by interactions between heart-forming tissues and the rest of the body. 

In fact, Nipbl deficiency in some tissues even seemed to protect against the development of atrial septal defects, in certain situations, the researchers explained.

"The study results show that heart defects such as ASDs occur when the heart does not grow quickly enough to meet the demands of the developing body -- in other words, that heart size and body size must be coordinated for the heart to develop without defects," said Anne Calof, Professor at University of California, at Irvine. 

"This is the first genetic demonstration that major risk factors for heart defects are likely to lie outside of the heart itself," Calof added, in the paper published in the journal PLOS Biology.

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) Before buying a product, consumers are often likely to search and review online hundreds of available items in any category for up to a month. However, what they purchase tends to be remarkably close to the items they searched and found in their very first search, says a study. "Consumers don't explore anywhere close to full range of products and attributes in the category. The final product they purchase is very close in terms of the attributes to the products they discovered on the first day," said Bart Bronnenberg of Tilburg University in the Netherlands. The study finds that about 25 per cent of consumers search and purchase in just one online session. The average purchase takes much longer -- around 15 days and over six sessions. The vast majority of purchases happen in under a month. Further, about 40 per cent of consumers search only one brand and 20 per cent only one model, while the average consumer will search about three brands and six models. "People differ in their search behaviour a lot. Some make up their mind right away but others search for long periods - often up to a month and review many products," added Carl Mela of Duke University in North Carolina, US. This suggests that consumers have a rough idea of the quality and type of features they want as they begin search. The search helps them merely to refine the right combination of features within the narrow range of features of the products they found on the first day. For marketers, a long period of search can be a great opportunity to influence the exploration and discovery of new products during search and purchase. "The fact that what people buy is close to what they initially found means that the advertising targeting and product recommendations can use this information effectively and recommend close variants of what the consumer initially searched and found," explained Jun Kim of the Hong Kong University of Science and Technology. The study focussed on online search and purchase behaviour of consumers in the digital camera category. The team combined detailed consumer online browsing and purchase data for digital cameras from the online measurement firm comScore, with scraped camera product pages from the three largest online retailers - Amazon, Best Buy, and Walmart - to uncover a variety of insights about online consumer search behaviour. They used a sample of more than 1,000 digital camera purchases with full browsing histories over a three-month period. The article is forthcoming in the journal Marketing Science

​New York, Sep 8 (IANS) How a car looks can go a long way in determine how much it sells and researchers, including one of Indian-origin, have now found what design elements prime a car's popularity. By combining data on aesthetic design and sales, the researchers showed that while customers do not like cars to look too different from the market average, they also do not want something that looks too similar. When buying a luxury car, it is more important that the car looks consistent with the brand, and less important that it looks like other cars in the market segment. Cars in the economy segment can gain in popularity by mimicking the aesthetics of their luxury counterparts, the study said. The findings will help marketing professionals make better decisions on aesthetic design, and can be applied to a wide range of product categories including electronics, wearable technologies and household appliances, said Subramanian "Bala" Balachander, Professor at University of California, Riverside, in the US. "Using our quantitative design model, product design managers in all sectors can forecast sales and profits of alternative aesthetic designs," Balachander said. Although quantifying the physical appearance of real products is challenging, the researchers used a recently developed morphing technique to construct the "average" car in a particular market segment or brand from a series of individual pictures. Once developed, the researchers determined the similarity of more than 200 car models from 33 brands sold in the US between 2003 and 2010 to that average, examining their segment prototypicality (how typical a product is compared to other products in the same market), brand consistency (how much a product looks like the average product in a brand's product lineup) and cross-segment mimicry (how much the design of an economy product mimics a luxury product), while controlling for other variables such as price and advertising. Their results, to be published in a forthcoming issue of the Journal of Marketing, showed that the aesthetic design of a product can have a significant effect on consumer preference, with consumers preferring products that are neither too similar to the average product nor drastically different.

​New York, Sep 8 (IANS) The sophisticated gadgetry in smartphones makes them ideal tools to steal sensitive data from 3-D printers, says a study.

That's according to a new University at Buffalo study that explores security vulnerabilities of 3-D printing, also called additive manufacturing, which analysts say will become a

​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.