Knowledge Update

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.​

​New York, March 21 (IANS) A weak ecosystem of bacteria in human gut due to a poor dietary diversity is likely to trigger diseases like Type 2 diabetes and obesity, finds new research, suggesting people to eat a balanced, diversed diet.

Changes in farming practices over the last 50 years have resulted in decreased agricultural diversity, which in turn has resulted in decreased dietary diversity.

The findings, published in the journal Molecular Metabolism, revealed that the reduction has changed the richness of the human gut microbiota and the community of microorganisms living in the gut.

"Healthy individuals posses a diverse gut microbiota but a reduced microbiotic richness gives rise to Type 2 diabetes, obesity and inflammatory bowel disease," said the team from Pennington Biomedical Research Centre in US.

Gut microbiota function as an endocrine organ, metabolising specific nutrients from the diet and producing specific substances that act as metabolic signals in the host. 

Like all healthy ecosystems, richness of microbiota species characterises the gut microbiome in healthy individuals. Conversely, a loss in species diversity is a common finding in several disease states. 

This microbiome is flooded with energy in the form of undigested and partially digested foods, and in some cases drugs and dietary supplements. 

Each microbiotic species in the biome transforms that energy into new molecules, which may signal messages to physiological systems of the host. 

The more diverse the diet, the more diverse the microbiome and the more adaptable it will be to perturbations, the researchers noted.​

​New York, March 21 (IANS) Chief of marketing and human resource officers need to better coordinate their activities to maximise a company's value, says a new research.

Customers and employees represent two critical stakeholders of a firm. In most organisations, customer-related activities are under the purview of marketing, while employee-related activities are under the purview of human resource. 

The results of the study showed that the relative consistency with which a company treats its customers and employees could affect the company's long-term value. 

Improving consistency in employee and customer achievements can lead to a big change for a firm both financially and metaphorically.

Also, the customer -- and employee -- related achievements could have a positive impact on a firm's valuation while the lapses can strengthen the negative impact. 

Companies that have consistency in employee and customer achievements on average have 11 percent higher firm valuation than those having inconsistent outcomes. 

"Our results imply that CEOs need to ensure that critical members of the C-suite coordinate their activities to maximize firm value," the researchers maintained.

The findings also revealed that the effect of uniformity in customer and employee related activities are stronger for firms with a narrow than a broad business scope.

"We found these results to be much stronger for firms with a narrow than a broad business focus; that is, competing in fewer than more business segments,” said Yan "Anthea" Zhang, the Fayez Sarofim Vanguard professor of Management at the Rice Jones University in Texas, US.

To achieve this oneness, it is critical for firms to ensure that their marketing and human-resource departments act in unison, the researchers asserted.

The authors found evidence to support their theory using a dataset of 21,447 observations between 1994 and 2010 that represented 4,643 firms. ​

​Toronto, March 18 (IANS) Opening up a whole new paradigm for treating or even indefinitely postponing the onset of osteoporosis, researchers have found that a single injection of stem cells could potentially restore the normal bone structure in those affected by the condition in which bones become brittle as a result of loss of tissue.

With age-related osteoporosis, the inner structure of the bone diminishes, leaving the bone thinner, less dense, and losing its function. 

The disease is responsible for an estimated 8.9 million fractures per year worldwide.

But how can an injection of stem cells reverse the ravages of age in the bones?

The researchers earlier demonstrated a causal effect between mice that developed age-related osteoporosis and low or defective mesenchymal stem cells (MSCs) in these animals.

"We reasoned that if defective MSCs are responsible for osteoporosis, transplantation of healthy MSCs should be able to prevent or treat osteoporosis," said senior author of the study William Stanford, professor at the University of Ottawa in Canada.

To test that theory, the researchers injected osteoporotic mice with MSCs from healthy mice.

Stem cells are "progenitor" cells, capable of dividing and changing into all the different cell types in the body. 

Able to become bone cells, MSCs have a second unique feature, ideal for the development of human therapies -- these stem cells can be transplanted from one person to another without the need for matching (needed for blood transfusions, for instance) and without being rejected.

After six months post-injection, a quarter of the life span of these animals, the osteoporotic bone had astonishingly given way to healthy, functional bone.

The findings were published in the journal Stem Cells Translational Medicine.

"We had hoped for a general increase in bone health," study co-author John Davies, professor at the University of Toronto, said. 

"But the huge surprise was to find that the exquisite inner "coral-like" architecture of the bone structure of the injected animals--which is severely compromised in osteoporosis--was restored to normal," Davies noted.

While there are currently no human stem cell trials looking at a systemic treatment for osteoporosis, the long-range results of the study point to the possibility that as little as one dose of stem cells might offer long-term relief.​

​New York, March 18 (IANS) A new equation developed by scientists can predict more accurately your walking energy expenditure, thus replacing the leading standardised equations used for close to half a century that were based on the assumption that one size fits all.

"Our new equation is formulated to apply regardless of the height, weight and speed of the walker. It's appreciably more accurate," said Lindsay Ludlow, a researcher at the Southern Methodist University (SMU) in Dallas.

The equation developed by SMU scientists, which was recently described in in the Journal of Applied Physiology, is about four times more accurate for adults and children together, and about two to three times more accurate for adults only, Ludlow said.

"The economy of level walking is a lot like shipping packages -- there is an economy of scale," said Peter Weyand, a study co-author. "Big people get better gas mileage when fuel economy is expressed on a per-pound basis," he added.

The research comes at a time when greater accuracy combined with mobile technology, such as wearable sensors, is increasingly being used in real time to monitor the body's status. 

The researchers note that some devices use the old standardised equations, while others use a different method to estimate the calories burned.​

New York, March 18 (IANS) Having more ideal cardiovascular health is linked with better brain processing speed and is more likely to prevent the decline in brain function that sometimes accompanies ageing, according to a study.

The researchers from the University of Miami and the Columbia University used the American Heart Association's "Life's Simple Seven" definition of cardiovascular health, which includes tobacco avoidance, ideal levels of weight, physical activity, healthy diet, blood pressure, cholesterol and glucose.

"Achieving the health metrics of Life's Simple 7 is associated with a reduced risk of strokes and heart attacks, even among the elderly," said study lead author Hannah Gardener from the University of Miami.

"The finding that they may also impact cognitive, or brain function underscores the importance of measuring, monitoring and controlling these seven factors by patients and physicians," Gardener added.

At the beginning of the study, published recently in Journal of the American Heart Association, 1,033 participants were tested for memory, thinking and brain processing speed.

Brain processing speed measures how quickly a person is able to perform tasks that require focused attention. Approximately six years later, 722 participants repeated the cognitive testing, which allowed researchers to measure performance over time.

The researchers found that having more cardiovascular health factors was associated with less decline over time in processing speed, memory and executive functioning, which is associated with focusing, time management and other cognitive skills.

"In addition, further study is needed to identify the age ranges, or periods over the life course, during which cardiovascular health factors and behaviours may be most influential in determining late-life cognitive impairment, and how behavioural and health modifications may influence cognitive performance and mitigate decline over time," Gardener said.​

​London, March 19 (IANS) A source of cosmic rays radiating energies 100 times greater than those achieved at the largest terrestrial particle accelerator -- the Large Hadron Collider at the European Organisation for Nuclear Research (CERN) -- has been found in the innermost region of our Milky Way galaxy.

The source was revealed after a detailed analysis of the data collected by the H.E.S.S. observatory in Namibia, which was published in the latest issue of the journal Nature. 

H.E.S.S. observatory is being run by an international collaboration of 42 institutions in 12 countries and has been mapping the centre of our galaxy in very high energy gamma rays for over the past 10 years.

"Somewhere within the central 33 light years of the Milky Way there is an astrophysical source capable of accelerating protons to energies of about one petaelectronvolt, continuously for at least 1,000 years," said Emmanuel Moulin from the Saclay Nuclear Research Centre in France. 

Cosmic rays with energies up to approximately 100 teraelectronvolts (TeV)1 are produced in our galaxy by objects such as supernova remnants and pulsar wind nebulae. 

Theoretical arguments and direct measurements of cosmic rays reaching the Earth indicate, however, that the cosmic-ray factories in our galaxy should be able to provide particles up to one petaelectronvolt (PeV)2 at least. 

While many multi-TeV accelerators have been discovered in recent years, the search for the sources of the highest energy Galactic cosmic rays has been unsuccessful.

The electrically-charged cosmic rays are strongly deflected by the interstellar magnetic fields that pervade our galaxy. Their path through the cosmos is randomised by these deflections, making it impossible to directly identify the astrophysical sources responsible for their production. 

Thus, for more than a century, the origin of the cosmic rays has remained one of the most enduring mysteries of science.

In analogy to the "Tevatron" -- the first human-built accelerator that reached energies of 1 TeV -- this new class of cosmic accelerator has been dubbed a "Pevatron."