Knowledge Update

Toronto, May 16 (IANS) For decades, scientists have fiercely debated whether rapid eye movement sleep -- the phase where dreams appear -- is directly involved in memory formation. Now, a study provides evidence that this is indeed the case.

Poor sleep quality is increasingly associated with the onset of various brain disorders such as Alzheimer's and Parkinson's disease.

Results from this study, published in the journal Science, suggest that disruption in this important phase of sleep may contribute directly to memory impairment observed in Alzheimer's disease, the researchers said.

"We were able to prove for the first time that REM sleep is indeed critical for normal spatial memory formation in mice," said study co-author Sylvain Williams, professor at McGill University in Montreal, Canada.

This phase of sleep is understood to be a critical component of sleep in all mammals, including humans.

For the study, the researchers used optogenetics, a recently developed technology that enables scientists to target precisely a number of neurons and control their activity by light.

"We chose to target neurons that regulate the activity of the hippocampus, a structure that is critical for memory formation during wakefulness and is known as the 'GPS system' of the brain," Williams said.

To test the long-term spatial memory of mice, the scientists trained the rodents to spot a new object placed in a controlled environment where two objects of similar shape and volume stand. 

Mice spend more time exploring a novel object than a familiar one, showing their use of learning and recall. 

When these mice were in REM sleep, however, the researchers used light pulses to turn off their memory-associated neurons to determine if it affects their memory consolidation. 

The next day, the same rodents did not succeed the memory task learned on the previous day. Compared to the control group, their memory seemed erased, or at least impaired.

"Silencing the same neurons for similar durations outside REM episodes had no effect on memory. This indicates that neuronal activity specifically during REM sleep is required for normal memory consolidation," study's lead author Richard Boyce from McGill University noted.​

The motor bike and sidecar used in a dramatic chase in one of the Harry Potter movies is to go on display on Monday at the Museum of Liverpool.

It will be a homecoming for the famous motor cycle with magical powers. Part of a dramatic chase in the blockbuster movie was filmed in the road tunnel under the Mersey river linking Liverpool with neighbouring Birkenhead on the opposite bank, Xinhua news agency reported.

The bike belonged to Harry Potter's loyal friend, the giant Hagrid, gamekeeper at the Hogwarts School, played in the movies by British actor Robbie Coltrane.

The machine will be on display at the museum until June 9.

In the film "Harry Potter and the Deathy Hallows Part 1", the quirky motor cycle combination which was originally owned by Harry's godfather Sirius Black, has a starring role.

Its big moment comes in a hair-raising scene as Harry, played by the actor Daniel Radcliffe, and Hagrid embark on a dangerous and dramatic chase through an underground road tunnel, which was actually filmed in the Liverpool tunnel.

The poster for "Harry Potter and the Deathly Hallows -- Part 1" features in the museum's popular exhibition Reel Stories: Liverpool and the Silver Screen (on display until September 2017), a celebration of Liverpool's starring role in films from the past 60 years through original film posters and memorabilia.

Museum urban history curator Paul Gallagher said: "We are delighted to be able to show Hagrid's bike during the run of our Reel Stories exhibition which examines Liverpool's remarkable ability to be a backdrop for filmmakers."

"We hope the motor cycle will be a hit with Harry Potter fans and film buffs."

For the technically minded, the actual bike is a Royal Enfield, Bullet 500 with a 499cc petrol engine. It was registered in 2009 and modified for the film in the same year, with a sidecar fitted.

The bike is on loan to the Museum of Liverpool from the Warner Bros. Studios, makers of the Harry Potter films.​

​London, May 15 (IANS)

​New York, May 15 (IANS) The proximity to snacks at workplace can increase your consumption behaviour, says a new study that focuses on how companies can promote healthy choices and still provide indulgent goodies.

Many companies provide free snacks and beverages to incentivise productivity and boost morale of its employees. However, unhealthy snacking may cause an office obesity epidemic.

The findings showed the proximity of snacks to free beverages increased the consumption rate.

The closer the snacks were placed to the drinks, the more people tended to eat, even a difference of a few feet mattered.

"It was a bit surprising that an extra few feet of distance between snacks and beverages yielded such a significant change in snacking frequency," said lead researcher Ernest Baskin, consumer behaviour expert and professor at Saint Joseph's University in the US.

Also, the snacking behaviour was found more in men as opposed to women.

"Factors that influence consumer behaviour without our full realisation, like convenience or relative proximity, are especially important to study to help educate individuals about healthy decision-making," Baskin noted.

The study, published in the journal Appetite, worked on how to provide the right kind of culinary indulgence that make an office so attractive to employees without.

Potential interventions for reducing snacking in the workplace include moving healthier snack options closer, or making unhealthy snacks more difficult to access (placing them in a pantry or in a free vending machine), the researchers suggested.​

​London, May 14 (IANS) Use by human societies in primordial trade routes has shaped the genetic diversity of the camel, famously known as the 'ship of the desert,' finds a interesting study of its ancient and modern DNA.

Single-humped 'Arabian camels', properly known as 'dromedaries' (Camelus dromedarius), have been fundamental to the development of human societies, providing food and transport in desert countries, for over 3000 years.

Researchers analysed genetic information from a sample of 1,083 living dromedaries from 21 countries across the world.

The findings showed that they were genetically very similar, despite populations being hundreds of miles apart.

Centuries of cross-continental trade caused this "blurring" of genetics, the researchers explained.

"Our analysis of this extensive dataset actually revealed that there is very little defined population structure in modern dromedaries. We believe this is a consequence of cross-continental back and forth movements along historic trading routes," said Olivier Hanotte, professor at Nottingham University in Britain.

"Our results point to extensive gene flow which affects all regions except East Africa where dromedary populations have remained relatively isolated," Hanotte added.

For the research, published in the journal Proceedings of the National Academy of Science, the team combined an examination of ancient DNA sequences from bone samples from early-domesticated dromedaries from 400-1870 AD and wild ones from 5,000-1,000 BC to reveal for the first time ever a historic genetic picture of the species.

"The genetic diversity we have discovered underlines the animal's potential to adapt sustainably to future challenges of expanding desert areas and global climate change," noted Faisal Almathen from King Faisal University in Saudi Arabia.

The dromedary continues to be a vital resource in trade and agriculture in hot, dry areas of the world, providing transport, milk and meat where other species would not survive. ​

​Washington, May 14 (IANS) The local atmosphere in Mars is clear in winter, dustier in spring and summer, and windy in autumn, show measurements by NASA's Curiosity rover that has completed recording environmental patterns through two full cycles of Martian seasons.

Curiosity this week completed its second Martian year since landing inside Gale Crater nearly four years ago. The repetition helps distinguish seasonal effects from sporadic events, NASA's Jet Propulsion Laboratory said in a statement.

Each Martian year -- the time it takes the Red Planet to orbit the sun once -- lasts 687 Earth days. 

Measurements of temperature, pressure, ultraviolet light reaching the surface and the scant water vapour in the air at Gale Crater show strong, repeated seasonal changes, the statement added.

Monitoring the modern atmosphere, weather and climate fulfills a Curiosity mission goal supplementing the better-known investigations of conditions billions of years ago. 

Back then, Gale Crater had lakes and groundwater that could have been good habitats for microbes, if Mars has ever had any. 

Today, though dry and much less hospitable, environmental factors are still dynamic, the statement added.

Curiosity measured air temperatures from 15.9 degrees Celsius on a summer afternoon, to minus 100 degrees Celsius on a winter night. 

"Curiosity's weather station has made measurements nearly every hour of every day, more than 34 million so far," said Curiosity project scientist Ashwin Vasavada of NASA's Jet Propulsion Laboratory, Pasadena, California. 

"The duration is important, because it's the second time through the seasons that lets us see repeated patterns," Vasavada noted.

The similar tilts of Earth and Mars give both planets a yearly rhythm of seasons. But some differences are great, such as in comparisons between day and night temperatures.

Even during the time of the Martian year when temperatures at Gale Crater rise above freezing during the day, they plummet overnight below minus minus 90 degrees Celsius, due to the thin atmosphere. 

Also, the more-elliptical orbit of Mars, compared to Earth, exaggerates the southern-hemisphere seasons, making them dominant even at Gale Crater's near-equatorial location.

"Mars is much drier than our planet, and in particular Gale Crater, near the equator, is a very dry place on Mars," Germán Martinez, Curiosity science-team collaborator at the University of Michigan, Ann Arbor. 

"The water vapor content is a thousand to 10 thousand times less than on Earth," Martinez said.

While continuing to study the modern local environment, Curiosity is investigating geological layers of lower Mount Sharp, inside Gale Crater, to increase understanding of ancient changes in environmental conditions, NASA said.​

​Brussels, May 15 (IANS) Michael Gillon and the team from the University of Liege started their research project five years ago. Only in September last year they discovered three planets orbiting around a nearby dwarf star known as Trappist 1.

As the size and temperatures of these three "red worlds" were comparable to the Earth and other planets from our solar system, it could be the best place for finding life, Xinhua news agency quoted Belgian scientists as saying.

"We are looking for planets that could have on their surfaces the conditions like on Earth and maybe host life," said Michael Gillon, a researcher.

The study showed two of the researched planets have orbital periods of about 1.5 days and 2.4 days respectively. Orbiting time of the third one is around 10 days, Gillon said.

"We are already preparing the next phase which will be the most interesting. It is the James Webb space telescope, which is a very big space telescope that will be launching in 2018, so two years from now and with this telescope we will be able to study atmosphere. So, currently we are trying to measure the masses of the planet," he said.

Scientists from Belgium cooperate with international researchers from the US and Britain. They mainly work through the internet system connected to one of the prototype telescope based in Chile.

To detect potentially habitable planets researchers use a so-called transit method. They observe specific stars and trying to catch the planet that will pass in front of them.

"We made this programme on our small robotic telescope Trappist which is in Chile as a prototype for our more ambitious project which is called Speculoos ... It will use bigger telescopes with more sensitive instruments to explore more," he added.

With current Trappist telescope scientists were able to observe only 60 targets. With Speculoos the scope will be wider, up to 500 objects.​

Beijing, May 15 (IANS) At times when we want something and things are unavailable, we end up picking the closest substitute. But a new study suggests that we would be better off and happy picking something that is not-so-similar alternative.

The findings indicated that even though people tend to prefer the option that is most similar to the item they cannot have, they are likely to be more satisfied with the option that diverges a bit.

"Intuition suggests the next best thing is the thing most like the thing we want, but our findings suggest this intuition is wrong," said lead study author Young Eun Huh of Hong Kong University of Science and Technology.

The intuition is wrong because it fails to account for the mental comparisons we end up making between what we wanted and what we ended up with.

"The thing that is most like what we want is also easiest to compare to what we are craving and we are likely to notice that it's worse than what we want," Huh explains.

The study, published in the journal of the Association for Psychological Science, examined 101 participants with different sets of foods on how making choices involving tradeoffs influences how satisfied we feel with those choices through a series of four experiments.

Each set included one desired food and two substitute options.

The majority of participants who tasted a piece of gourmet chocolate chose chocolate-covered peanuts over a granola bar as their preferred substitute; in fact, the stronger their craving for the chocolate, the more likely they were to choose the chocolate peanuts.

The findings provide insight into how we can maximise our satisfaction with the food we eat, given the choices available.

"Life often presents all of us with situations in which we can't have exactly what we want: We might not get our dream job or be able to afford the perfect vacation," the researchers noted.​

​London, May 14 (IANS) People with depression are significantly less likely to recover well after treatment for colorectal cancer compared to those without depression, new research has found.

The new study showed that one in five colorectal cancer patients are depressed at the time of diagnosis. 

These people are seven times more likely to have 'very poor health', which could include things like severe difficulty with walking around or being confined to bed, two years after treatment has ended compared to those without depression. 

They are also 13 times more likely to have 'very poor quality of life', which could include problems with thinking and memory or sexual functioning.

"Our study has highlighted the importance of taking into account psychological factors when thinking about how best to support patients recently diagnosed with colorectal cancer,” said Claire Foster, professor at University of Southampton in Britain.

“We have shown that self-reported depression before cancer treatment starts predicts quality of life and health status during treatment and up to two years later,” Foster noted.

The findings based on an analysis of lives of more than a thousand colorectal cancer patients were published in the journal PLOS ONE.

"This research tells us that having depression has an enormous impact on how people live after their cancer treatment,” Jane Maher, joint chief medical officer of Macmillan Cancer Support, a Britain-based charity organisation, said.

“In fact, it affects their recovery more than whether or not they've been diagnosed early. We know that depression and anxiety often go hand in hand with cancer but now we can see the extent to which people are struggling to live with these illnesses,” Maher noted.​

​Durban, May 14 (IANS) South Africa has identified India as a key focus market for boosting tourism and it will shortly launch an aggressive campaign to attract tourists from there.

South African Tourism Minister Derek Hanekom announced this at the INDABA tourism fair here. He said that the country had received more than 80,000 Indian tourists last year and his ministry planned to dedicate to India a significant part of its advertising budget of nearly $8 million this year, with the objective of boosting significantly the arrivals from India.

"India has a huge potential and our challenge is to see what is needed in order for this market to grow and for us to get a fair share of the huge pool of Indian travellers," Hanekom told this correspondent.

He said Indian travellers felt at home in South Africa as they had a very large population of people of Indian origin, especially in Durban.

"Mahatma Gandhi had also lived here in Durban. Here, just like in India, we have different cultures and different religions living in harmony with one another," he added.

INDABA, which means gathering in Zulu, has positioned itself as the largest tourism fair in the African continent and attracts participation from all African countries which come to display their new products and services, as tourism is an essential sector for creating employment as well as economic growth in the least developed continent in the world.

"The safari experience is certainly one of the key selling point of Africa. We don't have the Taj Mahal or some of the incredible sites that you have in India, but here in South Africa, you can be guaranteed to see the Big 5 (Lions, Elephants, Rhinos, Buffaloes and Leopards) in just one, single safari," Hanekom said.

Tourism to South Africa and other African countries was severely hit by fears arising from the fresh outbreak of Ebola epidemic in West African nations of Liberia, Sierre Leone and Guinea. The market has begun to show signs of recovery, now that the outbreak has subsided.

The minister said that tourists' fears were misplaced about contracting the virus in South Africa. "In fact, Europeans were much closer to where Ebola was happening than we were in South Africa," Hanekom said.

Apart from a subsiding Ebola, Hanekom placed his hopes on boosting arrivals from India on the ease of visa regulations for Indians visiting South Africa. Earlier, the visa regulations were strict and it would take up to three weeks for getting permission to travel. In April this year, after Hanekom's visit to India, the norms have been eased and visas should be easier and quicker to obtain for Indians.

"The problem is that our consulate and embassies were having difficulties in answering and handling the visa demands during the peak travel season in India and it often took up to three weeks for delivering visas. That is simply too long. I am convinced that if we manage to make the visa easier we can double the numbers in a couple of years," Hanekom explained.

For many Indians, the country is also perceived as an elite and expensive destination just like European countries, but in recent months a weakening Rand has allowed more Indians to visit and spend more.

Another peculiarity of the Indian travellers is that they like to visit several countries on a trip. While in Europe and North America it is simpler due to visa-free travel between nations, it is still a challenge in Africa.

This point was a focus of discussions at the INDABA this year and various African countries have begun looking at how to facilitate such seamless travel in Africa. Hanekom admitted that security and instability issues in some African nations remained an important barrier to visa-free travel within the continent.

The minister also allayed fears of travellers that that some areas in South Africa were unsafe.

Hanneli Slabber, country manager of South Africa Tourism in India, said: "I guess you have to beware of pickpockets anywhere in the world. Indians visiting South Africa enjoy adventure and activities and they buy triple the amount of activities than those from other nations. Indian women are actually leading in terms of numbers and they like the country and feel safe."

Slabber said that now a lot of vegetarian options, including vegan and Jain food, are available in the country and there were several Indian restaurants. "Our cuisine is influenced by Indian curries as well and a lot of South Africans, not necessarily of Indian origin, can cook good Indian cuisine," he added.

However, in a blow to tourism from India, the national carrier, South African Airways, facing a shortage of aircraft, has stopped the only direct flights from India (Mumbai) to South Africa, forcing Indian tourists to go for alternatives like Emirates or Qatar with one-stop flights.​

​Washington, May 13 (IANS) In a first, the US space agency has directly observed fundamental process of nature after sending four spacecraft through an invisible whirlpool in space called magnetic reconnection, like sending sensors up into a hurricane.

The findings showed that magnetic reconnection is dominated by the physics of electrons -- thus providing crucial information about what powers this fundamental process in nature.

Magnetic reconnection is one of the prime drivers of space radiation and a key factor in the quest to learn more about our space environment and protect our spacecraft and astronauts.

The effects of this sudden release of particles and energy -- such as giant eruptions on the sun or radiation storms in near-Earth space -- have been observed throughout the solar system and beyond.

"We developed a mission called the Magnetospheric Multiscale mission (MMS) that for the first time would have the precision needed to gather observations in the heart of magnetic reconnection," said Jim Burch, principal investigator at the Southwest Research Institute in San Antonio, Texas.

"We received results faster than we could have expected. By seeing magnetic reconnection in action, we have observed one of the fundamental forces of nature," he added.

MMS is made of four identical spacecraft that were launched in March 2015.

They fly in a pyramid formation to create a full 3D map of any phenomena they observe.

On October 16, 2015, the spacecraft travelled straight through a magnetic reconnection event at the boundary where Earth's magnetic field bumps up against the sun's magnetic field.

In only a few seconds, the 25 sensors on each of the spacecraft collected thousands of observations.

"One of the mysteries of magnetic reconnection is why it's explosive in some cases, steady in others, and in some cases, magnetic reconnection doesn't occur at all," noted Tom Moore, mission scientist for MMS at NASA's Goddard Space Flight Centre in Greenbelt, Maryland.

At the edges of Earth's magnetic environment - the magnetosphere - such events allow solar radiation to enter near-Earth space.

With this new set of observations, MMS tracked what happens to electrons during magnetic reconnection.

As the four spacecraft flew across the magnetosphere's boundary, they flew directly through what's called the dissipation region where magnetic reconnection occurred.

The observations showed the electrons shot away in straight lines from the original event at hundreds of miles per second, crossing the magnetic boundaries that would normally deflect them.

Once across the boundary, the particles curved back around in response to the new magnetic fields they encountered, making a U-turn.

By watching these electrons, MMS made the first observation of the predicted breaking and interconnection of magnetic fields in space.

"The data showed the entire process of magnetic reconnection to be fairly orderly and elegant," said Michael Hesse, space scientist at Goddard, in a paper published in the journal Science.

There does not seem to be much turbulence present, or at least not enough to disrupt or complicate the process.

This suggests that it is the physics of electrons that is at the heart of understanding how magnetic field lines accelerate the particles.

Since its launch, MMS has made more than 4,000 trips through the magnetic boundaries around Earth, each time gathering information about the way the magnetic fields and particles move.​