Knowledge Update

Beijing, Nov 12 (IANS) The satellite that China launched into space last year to explore dark matter - thought to be the invisible part of the cosmos - has already detected 1.6 billion particles, officials said on Saturday.

Scientists will now have to analyse the information gathered to try to understand what makes some matter five times more abundant than which is visible - composed of atoms - and thought to form the greater part of the universe, Efe news reported.

Scientists established the existence of dark matter in the 1970's due to its gravitational effects on visible matter although their knowledge about it is very scarce.

Head engineer of the satellite, Wu Jian, explained that researchers have reviewed the systems of calibrated devices to ensure maximum accuracy of their observations, reported the Times.

The satellite called Wukong was launched on December 17, 2015 and after almost a year in operation is currently in orbit at an altitude of 504 km, developing its operations normally.

This satellite includes a space telescope - China's first - which notes the direction, power and electrical load of high-energy space particles.

It is expected that during its first two years of operations, the telescope will look in all directions and after passing the first stage, focus its activity in areas where initial results look most promising.

China Saturday also successfully launched into space a new meteorological satellite, Yunhai-1, from Jiuquan base in the Gobi desert, aboard the Long March-2D rocket.

This satellite, developed by the Shanghai Academy of Spaceflight Technology, will be dedicated to atmospheric, marine and space observation, prevention of meteorological disasters along with carrying out scientific experiments.

​London, Nov 12 (IANS) Consciousness depends upon the way nerve cells communicate and on the degree to which they manage to differ in terms of their activity patterns, suggests a study.

To establish how the brain produces consciousness the researchers tested the neuronal activity in the brains of mice and compared how brain activity differs in conscious and anesthetised mice.

"We used a fluorescent protein that converts electrical signals into light signals. This enabled us to visualise the frequency and average amplitude of neuronal responses, and allowed us to reveal the existence of neuronal synchrony," said Mazahir T. Hasan, researcher with Charite's NeuroCure Cluster of Excellence, Germany.

Results suggested that consciousness is not simply dependent on the number of active neurons inside the cortex; instead, it seems to be dependent upon the way these nerve cells communicate and on the degree to which they manage to differ in terms of their activity patterns.

The awake cortex showed complex activity patterns, with individual cells firing at different times. Under anesthesia, all neurons displayed identical activity patterns and fired at the same time. 

"While one might expect the brain to cease its activity under anesthesia, in reality, the situation is quite different. Neurons remain highly active but change their communication mode. During unconsciousness they become highly synchonised -- in simple terms all neurons start doing the same thing," said Thomas Lissek, Neurobiologist from Heidelberg, Germany.

Another surprising finding was that neurons were more sensitive to environmental stimuli under anesthesia than when the brain was awake. 

"This is especially surprising, as anesthesia is used to block both pain and environmental stimuli during surgery. Some of the brain regions that are normally dedicated to tactile perception even responded to sound information," Lissek added.

These new insights into neuronal activity patterns provide information regarding the identity of the cellular parameters involved in producing consciousness and the loss of consciousness.

​London, Nov 12 (IANS) Physicists avoid highly mathematical work despite being trained in advanced mathematics, a new study suggests.

The study, published in the New Journal of Physics, shows that physicists pay less attention to theories that are crammed with mathematical details. 

The researchers found using statistical analysis of the number of citations to 2,000 articles in a leading physics journal, that articles are less likely to be referenced by other physicists if they have lots of mathematical equations on each page.

"We have already showed that biologists are put off by equations but we were surprised by these findings, as physicists are generally skilled in mathematics," said Tim Fawcett, researcher at the University of Exeter, Britain. 

According to the researchers, it is an important issue because it shows that there could be a disconnection between mathematical theory and experimental work which presents a potentially enormous barrier to all kinds of scientific progress.

The findings suggested improving the training of science graduates would not help, because physics students already receive extensive maths training before they graduate. 

Instead, they think the solution lies in clearer communication of highly technical work, such as taking the time to describe what the equations mean.

"Physicists need to think more carefully about how they present the mathematical details of their work, to explain the theory in a way that their colleagues can quickly understand. Ideally, the impact of scientific work should be determined by its scientific value, rather than by the presentational style," said Andrew Higginson, researcher at the University of Exeter, Britain.

The study suggests that there are real and widespread barriers to communicating mathematical work and that this is not because of poor training in mathematical skills, or because there is a social stigma about doing well in mathematics.

​London, Nov 12 (IANS) Mars is a primary target in the search for life outside Earth, and liquid water is the most important pre-requisite for life. But a team of international researchers has found that Mars is incredibly dry, and has been that way for millions of years.

"Evidence shows that more than three billion years ago Mars was wet and habitable. However, this latest research reaffirms just how dry the environment is today," said Christian Schroder, Lecturer at the University of Stirling in Britain

"For life to exist in the areas we investigated, it would need to find pockets far beneath the surface, located away from the dryness and radiation present on the ground," Schroder, who is also science team collaborator for NASA's Mars Exploration Rover Opportunity mission, noted.

The discovery, published in the journal Nature Communications, provides vital insight into the planet's current environment and shows how difficult it would be for life to exist on Mars today.

Using data from the Opportunity mission, the scientists examined a cluster of meteorites at Meridiani Planum -- a plain just south of the planet's equator and at a similar latitude to Gale crater.

The researchers calculated a chemical weathering rate for Mars, in this case how long it takes for rust to form from the metallic iron present in meteorites.

This chemical weathering process depends on the presence of water. It takes at least 10 and possibly up to 10,000 times longer on Mars to reach the same levels of rust formation than in the driest deserts on Earth and points to the present-day extreme aridity that has persisted on Mars for millions of years, the study said.

A study published last year, which used data from the Curiosity Rover investigating Gale crater on Mars, suggested that very salty liquid water might be able to condense in the top layers of Martian soil overnight.

"But, as our data show, this moisture is much less than the moisture present even in the driest places on Earth," Schroder explained.

New York, Nov 11 (IANS) A special type of iPad game effectively helped in treating children with amblyopia in restoring their visual abilities, more than the standard treatment, researchers say.

​Marrakech, Nov 11 (IANS) The Africa50 Fund is willing to invest in Morocco and turn the country into a hub to invest in other African countries, said its Chief Executive Officer (CEO).

New York, Nov 11 (IANS) People who sleep five or fewer hours a night are likely to drink significantly more sugary caffeinated drinks, such as sodas and energy drinks, according to a new study

"We think there may be a positive feedback loop where sugary drinks and sleep loss reinforce one another, making it harder for people to eliminate their unhealthy sugar habit," said Aric A. Prather, assistant professor at the University of California San Francisco.

"This data suggests that improving people's sleep could potentially help them break out of the cycle and cut down on their sugar intake, which we know to be linked to metabolic disease," Prather added.

To understand whether this is a more general pattern in the adult population, the researchers in the study published in the journal Sleep Health analysed the records of around 18,000 participants.

The study included participants' reports of how much sleep they usually got during the work week, as well as their total consumption of various beverages, including caffeinated and non-caffeinated sugar-sweetened beverages, fruit juice, drinks with artificial sweeteners, and plain coffee, tea and water.

The researchers found that people who regularly slept five or fewer hours per night also drank 21 per cent more caffeinated sugar-sweetened beverages -- including both sodas and non-carbonated energy drinks -- than those who slept seven to eight hours a night.

People who slept six hours per night regularly consumed 11 per cent more caffeinated sugar-sweetened beverages. On the other hand, the team found no association between sleep duration and consumption of juice, tea or diet drinks.

"Sleeping too little and drinking too many sugary drinks have both been linked to negative metabolic health outcomes, including obesity," Prather added.

Enhancing the duration and quality of sleep could be a useful new intervention for improving the health and well-being of people who drink a lot of sugary beverages, the study suggests

​New Delhi, Nov 13 (IANS) Twenty-three-year-old Rahul (name changed) faced an unusual problem. He used to suffer dizziness, anxiety and regular headaches every time after having a meal. When the problem persisted, he decided to see a doctor and on investigation it was found that the root of the problem was an unusual condition where the blood sugar level drops after a meal instead of rising as is the norm.

Rahul was diagnosed with a relatively uncommon condition called reactive hypoglycemia, or postprandial hypoglycemia, which happens due to excess insulin secretion after a meal.

"The family history of diabetes could have been the reason for the excess insulin secretion," Ajay Kumar Ajmani, Senior Consultant, Endocrinology, BLK Super Speciality Hospital here, told IANS.

Although extreme cases of reactive hypoglycemia are very rare, doctors say that people with insulin resistance and those who are overweight or obese are vulnerable to this condition.

Insulin resistance is a risk factor for the development of Type-2 diabetes, which is increasing in epidemic proportions worldwide -- and more so in India.

Postprandial hypoglycemia occurs when too much insulin is produced and released by the pancreas following a large carbohydrate-based meal.

"Reactive hypoglycemia refers to low blood sugar that occurs after a meal -- usually within four hours after eating. This is different from low blood sugar (hypoglycemia) that occurs while fasting," Subhash Kumar Wangnoo, Senior Consultant Endocrinologist and Diabetologist at the capital's Indraprastha Apollo Hospital, told IANS.

"People who have undergone bariatric surgery (for weight loss) are also more likely to get reactive hypoglycaemia," Wangnoo noted. "In those who have undergone bariatric surgery, the food can pass too quickly into the small intestine (dumping syndrome). As a result, the glucose in food is not absorbed resulting in hypoglycaemia.

"Also an uncommon complication of bariatric surgery is nesidioblastosis -- a condition in which the insulin producing cells of the pancreas undergo hyperplasia, resulting in excess insulin production that can cause reactive hypoglycaemia," Wangnoo explained.

Signs and symptoms of reactive hypoglycemia include hunger, weakness, shakiness, sleepiness, sweating, light-headedness, headache, palpitations, irritability and anxiety.

"Increasing use of carbohydrates and fats and processed foods, along with reduced physical activity, are the underlying factors leading to the increasing prevalence of these conditions," Wangnoo said.

A study published in the journal Diabetologia detailed the history of three patients who did not have diabetes but who suffered so much from severe hypoglycemia following meals that they became confused and sometimes blacked out. Following weight loss surgery, all three patients -- a woman in her 20s, another in her 60s and a man in his 40s - developed postprandial hypoglycemia that failed to respond to dietary or medical intervention.

The immediate cause of hypoglycemia was exceptionally high levels of insulin following meals. All three patients in the study failed to respond to medication and ultimately required partial or complete removal of the pancreas, the major source of insulin, to prevent dangerous declines in blood glucose.

Thankfully, most cases of postprandial hypoglycemia can be managed by simple modifications in the diet, according to the doctors.

After monitoring blood glucose levels hourly before and after a meal, Rahul's diet too was modified.

"Rahul takes small meals every four hours, exercises daily in the morning and his blood sugar level does not dip below 80 mg/dL. After two months, he seemed to have got rid of the symptoms he used to complain of," Ajmani said.

"Dietary modification with controlled carbohydrate content has been demonstrated to improve symptoms of postprandial hypoglycemia in bariatric surgery-associated hypoglycemia, dumping syndrome, insulin autoimmunity, and postprandial syndrome," Manoj Kumar, Consultant, Endocrinology Department, Jaypee Hospital, Noida, noted.

The doctors advised that patients diagnosed with the condition should have a balanced diet -- high-fibre foods, non-meat source of protein, whole grains, fruits and vegetables. They should also avoid sugary food on an empty stomach.

"Avoid sugary soft drinks and eat several small meals and snacks throughout the day, no more than three hours apart during the waking hours," Ajmani said.

Patients with reactive hypoglycaemia should be screened for diabetes or later development of diabetes as they might be having prediabetes, Wangnoo pointed out.

Washington, Nov 11 (IANS) In a first-of-its-kind collaboration, NASA's Spitzer and Swift space telescopes joined forces to reveal a brown dwarf - thought to be the missing link between planets and stars, with masses up to 80 times that of our solar system's most massive planet, Jupiter.

The discovery of this brown dwarf, with the unwieldy name OGLE-2015-BLG-1319, marks the first time two space telescopes have collaborated to observe a microlensing event -- when a distant star brightens due to the gravitational field of at least one foreground cosmic object, NASA said in a statement on Thursday.

"We want to understand how brown dwarfs form around stars, and why there is a gap in where they are found relative to their host stars," said Yossi Shvartzvald from NASA's Jet Propulsion Laboratory, Pasadena, California, and lead author of a study published in the Astrophysical Journal. 

Spitzer and Swift observed the microlensing event after being tipped off by ground-based microlensing surveys, including the Optical Gravitational Lensing Experiment (OGLE). 

By combining data from these space-based and ground-based telescopes, researchers determined that the newly discovered brown dwarf is between 30 and 65 Jupiter masses.

They also found that the brown dwarf orbits a K dwarf, a type of star that tends to have about half the mass of the sun. 

"In the future, we hope to have more observations of microlensing events from multiple viewing perspectives, allowing us to probe further the characteristics of brown dwarfs and planetary systems," co-author of the study Geoffrey Bryden Jet Propulsion Laboratory.

​Tokyo, Nov 11 (IANS) More than half of Japan's largest coral reef has been destroyed due to the rise in water temperatures this year, says a study released by the Ministry of Environment on Friday.

The reef, located in front of Ishigaki island in Okinawa and protected as a natural reserve, boasts over 70 coral species and is considered one of the oldest and largest in the northern hemisphere, Efe news reported.

Ninety-seven per cent of the corals have undergone bleaching and 56 per cent have died, according to the ministry study which analysed the reef between September and October.

The deterioration was attributed to the 2 degree Celsius rise in average water temperatures in the area and the ministry warned that the remaining corals are at risk of disappearing in these conditions.

The meteorological phenomenon of El Nino, which causes temperatures of the sea surface to rise, has contributed to the coral bleaching around the world this year, including some of the largest protected reefs in Australia, Thailand and Maldives.

Coral bleaching occurs when they are faced with constant and extreme changes of temperature, light and nutrients.

This process puts at risk the abundance of fish species that depend on the reefs for their shelter and food.

In the Indian and Pacific oceans, if greenhouse gas emissions continue at the current level, fish stocks could diminish between 10 and 30 per cent by 2050 compared to the 1970-2000 period, according to data from the International Union for Conservation of Nature.