Taking care of grandkids one day a week helps keep grandmothers mentally sharp, finds a study from the Women's Healthy Aging Project study in Australia, published online today in Menopause, the journal of The North American Menopause Society (NAMS). That's good news for women after menopause, when women need to lower their risks of developing Alzheimer's disease and other cognitive disorders.
On the other hand, taking care of grandchildren five days a week or more had some negative effects on tests of mental sharpness. "We know that older women who are socially engaged have better cognitive function and a lower risk of developing dementia later, but too much of a good thing just might be bad," said NAMS Executive Director Margery Gass, MD.
The 186 Australian women, ages 57 to 68, took three different tests of mental sharpness and also noted whether they thought their own children had been particularly demanding of them in the last year. Among the 120 grandmothers, those who spent one day a week taking care of grandchildren performed best on two of the three tests. But those taking care of grandchildren for five or more days a week did significantly worse on one of the tests, which assesses working memory and mental processing speed.
That was a finding the researchers didn't expect. However, they also found that the more time grandmothers spent taking care of the grandchildren, the more they felt that their children had been more demanding of them, so maybe mood plays a role in the unexpected result. The investigators are already following up with more research.
Although other research has looked at the relationship between mental sharpness and being socially engaged, this is the first time that this type of research has looked at grandmothering. "Because grandmothering is such an important and common social role for postmenopausal women, we need to know more about its effects on their future health," says Dr. Gass. "This study is a good start."
Showing posts with label Science. Show all posts
Showing posts with label Science. Show all posts
Friday, April 18, 2014
Thursday, April 17, 2014
Watching movies synchronises viewers' brains
When we watch a movie, our brains react to it immediately in a way similar to brains of other people, scientists have found.
When we watch a movie, our brains react to it immediately in a way similar to brains of other people, scientists have found.
Researchers at Aalto University in Finland have developed a method fast enough to observe immediate changes in the function of the brain even when watching a movie.
Researchers said by employing movies it was possible to investigate the function of the human brain in experimental conditions that are close to natural.
Traditionally, in neuroscience research, simple stimuli, such as checkerboard patterns or single images, have been used.
Viewing a movie creates multilevel changes in the brain function. Despite the complexity of the stimulus, the elicited brain activity patterns show remarkable similarities across different people - even at the time scale of fractions of seconds.
"The analysis revealed important similarities between brain signals of different people during movie viewing," said researcher Kaisu Lankinen.
"These similar kinds or synchronised signals were found in brain areas that are connected with the early-stage processing of visual stimuli, detection of movement and persons, motor coordination and cognitive functions.
"The results imply that the contents of the movie affected certain brain functions of the subjects in a similar manner," Lankinen said.
So far, studies in this field have mainly been based on functional magnetic resonance imaging (fMRI). However, given the superior temporal resolution, within milliseconds, magnetoencephalography (MEG) is able to provide more complete picture of the fast brain processes.
With the help of MEG and new analysis methods, investigation of significantly faster brain processes is possible and it enables detection of brain activity in frequencies higher than before.
In the new analysis, brain imaging was combined with machine-learning methodology, with which signals of a similar form were mined from the brain data.
When we watch a movie, our brains react to it immediately in a way similar to brains of other people, scientists have found.
Researchers at Aalto University in Finland have developed a method fast enough to observe immediate changes in the function of the brain even when watching a movie.
Researchers said by employing movies it was possible to investigate the function of the human brain in experimental conditions that are close to natural.
Traditionally, in neuroscience research, simple stimuli, such as checkerboard patterns or single images, have been used.
Viewing a movie creates multilevel changes in the brain function. Despite the complexity of the stimulus, the elicited brain activity patterns show remarkable similarities across different people - even at the time scale of fractions of seconds.
"The analysis revealed important similarities between brain signals of different people during movie viewing," said researcher Kaisu Lankinen.
"These similar kinds or synchronised signals were found in brain areas that are connected with the early-stage processing of visual stimuli, detection of movement and persons, motor coordination and cognitive functions.
"The results imply that the contents of the movie affected certain brain functions of the subjects in a similar manner," Lankinen said.
So far, studies in this field have mainly been based on functional magnetic resonance imaging (fMRI). However, given the superior temporal resolution, within milliseconds, magnetoencephalography (MEG) is able to provide more complete picture of the fast brain processes.
With the help of MEG and new analysis methods, investigation of significantly faster brain processes is possible and it enables detection of brain activity in frequencies higher than before.
In the new analysis, brain imaging was combined with machine-learning methodology, with which signals of a similar form were mined from the brain data.
Wednesday, April 16, 2014
Targeting mosquito sperm can help combat malaria
Anopheles gambiae mosquitoes are the main transmitters of malaria, which affects around 200 million people every year.
Scientists have discovered a way of reducing the fertility of malaria-carrying mosquitoes by targeting an enzyme that protects their sperm, potentially providing a new tactic to combat the disease.
Anopheles gambiae mosquitoes are the main transmitters of malaria, which affects around 200 million people every year. The females mate only once during their lives.
They store the sperm from this single mating in an organ called the spermatheca, from which they repeatedly take sperm over the course of their lifetime to fertilise the eggs that they lay. The female needs the sperm to stay healthy whilst they are in storage in the spermatheca, so that they are viable each time she uses them to reproduce.
The new research shows that the sperm are partly protected by the actions of an enzyme called HPX15. When the researchers interfered with HPX15 in female A gambiae mosquitoes in the laboratory, the females fertilised fewer eggs and therefore produced fewer offspring. This is the first time that scientists have discovered a mechanism that preserves the function of sperm in A gambiae.
The researchers, from Harvard School of Public Health, the University of Perugia and Imperial College London, believe that their insight could ultimately lead to a new weapon in the fight against malaria. This would work by disabling HPX15 to reduce female fertility and through that, reduce the number of malaria-carrying mosquitoes in circulation.
“Malaria kills over 650,000 people every year and we need to find new ways of tackling it, partly because mosquitoes continue to evolve ways of resisting our efforts,” Dr Robert Shaw, one of the lead authors of the research, said. “We are interested in cutting the numbers of malarial mosquitoes by impairing their ability to reproduce, and our new study suggests a way that we might be able to do this.
“There is no single magic bullet for tackling malaria, but making mosquitoes less fertile could provide us with a valuable weapon against the disease,” said Shaw. The study suggests that HPX15 may protect the stored sperm against potentially damaging molecules called free radicals, which are particularly abundant after a female takes a blood feed.
Ensuring that the sperm are healthy after blood-feeding is important for the female’s fertility as she reproduces after each feed, fertilising her eggs with sperm released from the spermatheca. The study was published in the journal Proceedings of the National Academy of Sciences.
Scientists have discovered a way of reducing the fertility of malaria-carrying mosquitoes by targeting an enzyme that protects their sperm, potentially providing a new tactic to combat the disease.
Anopheles gambiae mosquitoes are the main transmitters of malaria, which affects around 200 million people every year. The females mate only once during their lives.
They store the sperm from this single mating in an organ called the spermatheca, from which they repeatedly take sperm over the course of their lifetime to fertilise the eggs that they lay. The female needs the sperm to stay healthy whilst they are in storage in the spermatheca, so that they are viable each time she uses them to reproduce.
The new research shows that the sperm are partly protected by the actions of an enzyme called HPX15. When the researchers interfered with HPX15 in female A gambiae mosquitoes in the laboratory, the females fertilised fewer eggs and therefore produced fewer offspring. This is the first time that scientists have discovered a mechanism that preserves the function of sperm in A gambiae.
The researchers, from Harvard School of Public Health, the University of Perugia and Imperial College London, believe that their insight could ultimately lead to a new weapon in the fight against malaria. This would work by disabling HPX15 to reduce female fertility and through that, reduce the number of malaria-carrying mosquitoes in circulation.
“Malaria kills over 650,000 people every year and we need to find new ways of tackling it, partly because mosquitoes continue to evolve ways of resisting our efforts,” Dr Robert Shaw, one of the lead authors of the research, said. “We are interested in cutting the numbers of malarial mosquitoes by impairing their ability to reproduce, and our new study suggests a way that we might be able to do this.
“There is no single magic bullet for tackling malaria, but making mosquitoes less fertile could provide us with a valuable weapon against the disease,” said Shaw. The study suggests that HPX15 may protect the stored sperm against potentially damaging molecules called free radicals, which are particularly abundant after a female takes a blood feed.
Ensuring that the sperm are healthy after blood-feeding is important for the female’s fertility as she reproduces after each feed, fertilising her eggs with sperm released from the spermatheca. The study was published in the journal Proceedings of the National Academy of Sciences.
Monday, April 14, 2014
'I will do it tomorrow' attitude hidden in genes
Those who procrastinate are also likely to be more impulsive and both the traits are linked to genes that one inherits, the study has found.
"Everyone procrastinates at least sometimes but we wanted to explore why some people procrastinate more than others and why procrastinators seem more likely to make rash actions and act without thinking," said psychological scientist Daniel Gustavson of the University of Colorado Boulder in the US.
The researchers found that procrastination is indeed heritable, just like impulsivity. Not only that, there seems to be a complete genetic overlap between procrastination and impulsivity - that is, there are no genetic influences that are unique to either trait alone, the study found.
For the study, researchers had 181 identical-twin pairs and 166 fraternal-twin pairs complete several surveys intended to probe their tendencies toward impulsivity and procrastination, as well as their ability to set and maintain goals.
The research appeared in the journal Psychological Science.
"Everyone procrastinates at least sometimes but we wanted to explore why some people procrastinate more than others and why procrastinators seem more likely to make rash actions and act without thinking," said psychological scientist Daniel Gustavson of the University of Colorado Boulder in the US.
The researchers found that procrastination is indeed heritable, just like impulsivity. Not only that, there seems to be a complete genetic overlap between procrastination and impulsivity - that is, there are no genetic influences that are unique to either trait alone, the study found.
For the study, researchers had 181 identical-twin pairs and 166 fraternal-twin pairs complete several surveys intended to probe their tendencies toward impulsivity and procrastination, as well as their ability to set and maintain goals.
The research appeared in the journal Psychological Science.
Sunday, April 13, 2014
'Red' letter day: India's Mars mission crosses halfway mark
Bangalore: Mangalyaan, India's maiden mission to Mars, crossed the halfway mark of its incredible journey today morning at 9.50 am.
Mangalyaan (Mars craft), which was launched on November 5, 2013 from the Sriharikota spaceport in Andhra Pradesh, has travelled nearly 337.5 million km till now.
It is expected to rendezvous with the Red Planet on September 24, 2014, when it will become the farthest any Indian object has ever travelled.
At Rs. 450 crore, India's Mars mission is the cheapest inter planetary mission ever undertaken.
Mangalyaan aims to look for signs of life on Mars. It also aspires to fulfill India's covert desire to beat China in the race to the Red Planet.
The mission seems to be on track thanks to the nature of planetary forces and the precise orbit injection by the Indian Space Research Organisation.
A team comprising nearly 500 ISRO scientists had worked tirelessly to ensure that Mangalyaan was ready for its launch within a record 15 months.
Of the 51 missions to Mars launched from across the world till date, 27 have failed so far.
If Mangalyaan manages to reach Mars, India will become the first country to achieve the enviable feat on a spacecraft 's maiden flight.
Till date, only the United States, Russia and the European Space Agency have successfully managed to send a spacecraft all the way to Mars.
Prime Minister Manmohan Singh had announced the Centre's decision to undertake a mission to Mars during his speech at the Red Fort on August 15, 2012.
From simply being an ambitious idea by the Indian government to an actual inter planetary mission that has crossed its halfway mark, it has been quite a remarkable journey for Mangalyaan.
Mangalyaan (Mars craft), which was launched on November 5, 2013 from the Sriharikota spaceport in Andhra Pradesh, has travelled nearly 337.5 million km till now.
It is expected to rendezvous with the Red Planet on September 24, 2014, when it will become the farthest any Indian object has ever travelled.
At Rs. 450 crore, India's Mars mission is the cheapest inter planetary mission ever undertaken.
Mangalyaan aims to look for signs of life on Mars. It also aspires to fulfill India's covert desire to beat China in the race to the Red Planet.
The mission seems to be on track thanks to the nature of planetary forces and the precise orbit injection by the Indian Space Research Organisation.
A team comprising nearly 500 ISRO scientists had worked tirelessly to ensure that Mangalyaan was ready for its launch within a record 15 months.
Of the 51 missions to Mars launched from across the world till date, 27 have failed so far.
If Mangalyaan manages to reach Mars, India will become the first country to achieve the enviable feat on a spacecraft 's maiden flight.
Till date, only the United States, Russia and the European Space Agency have successfully managed to send a spacecraft all the way to Mars.
Prime Minister Manmohan Singh had announced the Centre's decision to undertake a mission to Mars during his speech at the Red Fort on August 15, 2012.
From simply being an ambitious idea by the Indian government to an actual inter planetary mission that has crossed its halfway mark, it has been quite a remarkable journey for Mangalyaan.
Saturday, April 12, 2014
Couch potatoes date back 7,000 years
Thought couch potatoes are the product of a modern lifestyle? They may have evolved 7,000 years ago!
Thought couch potatoes are the product of a modern lifestyle? They may have evolved 7,000 years ago!
A new Cambridge study has shown that couch potatoes have a history that stretches back 7,000 years when humans first picked up the plough.
Research into lower limb bones shows that our early farming ancestors in Central Europe became less active as their tasks diversified and technology improved.
Cambridge University anthropologist Alison Macintosh found that this drop in mobility was particularly marked in men.
Macintosh shows that after the emergence of agriculture in Central Europe from around 5300 BC, the bones of those living in the fertile soils of the Danube river valley became progressively less strong, pointing to a decline in mobility and loading.
Macintosh suggests that male mobility among earliest farmers (around 7,300 years ago) was, on average, at a level near that of today's student cross-country runners.
Within just over 3,000 years, average mobility had dropped to the level of those students rated as sedentary, after which the decline slowed.
Macintosh laser-scanned skeletons found in cemeteries across Central Europe.
The earliest skeletons she examined date from around 5300 BC and the most recent from around 850 AD - a time span of 6,150 years.
Using a portable desktop 3D laser surface scanner to scan femora and tibiae, she found that male tibiae became less rigid and that bones in both males and females became less strengthened to loads in one direction more than another, such as front-to-back in walking.
These findings all indicate a drop in mobility. In other words, it is likely that the people to whom the skeletons belonged became, over generations, less intensely active and probably covered less distance, or carried out less physically demanding tasks, than those who had lived before them.
"My results suggest that, following the transition to agriculture in Central Europe, males were more affected than females by cultural and technological changes that reduced the need for long-distance travel or heavy physical work," said Macintosh.
"This also means that, as people began to specialise in tasks other than just farming and food production, such as metalworking, fewer people were regularly doing tasks that were very strenuous on their legs," Macintosh said.
Thought couch potatoes are the product of a modern lifestyle? They may have evolved 7,000 years ago!
A new Cambridge study has shown that couch potatoes have a history that stretches back 7,000 years when humans first picked up the plough.
Research into lower limb bones shows that our early farming ancestors in Central Europe became less active as their tasks diversified and technology improved.
Cambridge University anthropologist Alison Macintosh found that this drop in mobility was particularly marked in men.
Macintosh shows that after the emergence of agriculture in Central Europe from around 5300 BC, the bones of those living in the fertile soils of the Danube river valley became progressively less strong, pointing to a decline in mobility and loading.
Macintosh suggests that male mobility among earliest farmers (around 7,300 years ago) was, on average, at a level near that of today's student cross-country runners.
Within just over 3,000 years, average mobility had dropped to the level of those students rated as sedentary, after which the decline slowed.
Macintosh laser-scanned skeletons found in cemeteries across Central Europe.
The earliest skeletons she examined date from around 5300 BC and the most recent from around 850 AD - a time span of 6,150 years.
Using a portable desktop 3D laser surface scanner to scan femora and tibiae, she found that male tibiae became less rigid and that bones in both males and females became less strengthened to loads in one direction more than another, such as front-to-back in walking.
These findings all indicate a drop in mobility. In other words, it is likely that the people to whom the skeletons belonged became, over generations, less intensely active and probably covered less distance, or carried out less physically demanding tasks, than those who had lived before them.
"My results suggest that, following the transition to agriculture in Central Europe, males were more affected than females by cultural and technological changes that reduced the need for long-distance travel or heavy physical work," said Macintosh.
"This also means that, as people began to specialise in tasks other than just farming and food production, such as metalworking, fewer people were regularly doing tasks that were very strenuous on their legs," Macintosh said.
Thursday, April 10, 2014
Researchers reveal theory behind creation of Earth’s tectonic plates
Starting roughly four billion years ago, cooler parts of earth's crust were pulled downwards into the warmer upper mantle, damaging and weakening the surrounding crust. The process happened again and again until the weak areas formed plate boundaries.
"Over a much longer period, the same process could have created many tectonic plates. We have got a physical mechanism to explain how it could have happened," study author David Bercovici from Yale University explained.
The process began about four billion years ago and caused complete fractures some three billion years ago.
To investigate how the plates formed, Bercovici and Yanick Ricard of University of Lyon in France developed a computer model of earth's crust as it may have existed billions of years ago.
The model included a low-pressure zone at the base of the crust which caused a piece of the crust to sink into the upper mantle - mimicking conditions thought to have occurred early in the earth's history.
As the process repeated over time, it created a large tectonic plate with an active subduction zone.
Prior studies suggested the age of the plates - based on evidence of subduction gathered from minerals - preserved in ancient rocks.
In geology, subduction is the process that takes place at convergent boundaries by which one tectonic plate moves under another tectonic plate and sinks into the mantle as the plates converge.
The oldest such specimens are four-billion-year-old zircons found in the Jack Hills of Australia that appear to have formed at temperatures and pressures that are indicative of subduction.
"The subsequent movement of the plates has erased much of the evidence of their origin," said Paul Tackley, a geophysicist at Swiss Federal Institute of Technology (ETH) in Zurich, Switzerland in a report published in Nature.
According to Robert Stern, a geologist at University of Texas in Dallas, there is no firm evidence of plate tectonics earlier than one billion years ago, but the new mechanism behind plate formation is "the first interesting example of how it might have occurred".
"Over a much longer period, the same process could have created many tectonic plates. We have got a physical mechanism to explain how it could have happened," study author David Bercovici from Yale University explained.
The process began about four billion years ago and caused complete fractures some three billion years ago.
To investigate how the plates formed, Bercovici and Yanick Ricard of University of Lyon in France developed a computer model of earth's crust as it may have existed billions of years ago.
The model included a low-pressure zone at the base of the crust which caused a piece of the crust to sink into the upper mantle - mimicking conditions thought to have occurred early in the earth's history.
As the process repeated over time, it created a large tectonic plate with an active subduction zone.
Prior studies suggested the age of the plates - based on evidence of subduction gathered from minerals - preserved in ancient rocks.
In geology, subduction is the process that takes place at convergent boundaries by which one tectonic plate moves under another tectonic plate and sinks into the mantle as the plates converge.
The oldest such specimens are four-billion-year-old zircons found in the Jack Hills of Australia that appear to have formed at temperatures and pressures that are indicative of subduction.
"The subsequent movement of the plates has erased much of the evidence of their origin," said Paul Tackley, a geophysicist at Swiss Federal Institute of Technology (ETH) in Zurich, Switzerland in a report published in Nature.
According to Robert Stern, a geologist at University of Texas in Dallas, there is no firm evidence of plate tectonics earlier than one billion years ago, but the new mechanism behind plate formation is "the first interesting example of how it might have occurred".
Monday, March 10, 2014
World's first 3D fingerprint developed by Indian-American scientist
A team of Michigan State University computer scientists led by Indian Institute of Technology (IIT) Kanpur alum Anil Jain have built the first three-dimensional model of a human fingerprint.
What Jain, a University Distinguished Professor of computer science and engineering, and his team did was develop a method that takes a two-dimensional image of a fingerprint and maps it to a 3-D finger surface.
The 3-D finger surface, complete with all the ridges and valleys that make up the human fingerprint, is made using a 3-D printer. It creates what Jain's team called a fingerprint "phantom."
"In health care, a 3-D heart or kidney can be created," Jain said. "Because the dimensions are known, they can be put into a scanner and the imaging system can be calibrated."
While the 3-D model doesn't yet have the exact texture or feel of a real finger, it could advance fingerprint sensing and matching technology.
"Tools like this would help improve the overall accuracy of fingerprint-matching systems, which eventually leads to better security in applications ranging from law enforcement to mobile phone unlock," Jain said.
Members of Jain's team include Sunpreet Arora, a computer science doctoral student, Kai Cao, a research associate in computer science and engineering and research collaborator Nick Paulter at the National Institute of Standards and Technology
Jain, who has a B.Tech degree from IIT Kanpur and MS and PhD degrees from Ohio State University, has six US patents on fingerprint matching and has written a number of books on biometrics and fingerprint/facial recognition.
Additionally, Jain has also received a number of prestigious awards for contributions to pattern recognition and biometrics.
SOURCE
What Jain, a University Distinguished Professor of computer science and engineering, and his team did was develop a method that takes a two-dimensional image of a fingerprint and maps it to a 3-D finger surface.
The 3-D finger surface, complete with all the ridges and valleys that make up the human fingerprint, is made using a 3-D printer. It creates what Jain's team called a fingerprint "phantom."
"In health care, a 3-D heart or kidney can be created," Jain said. "Because the dimensions are known, they can be put into a scanner and the imaging system can be calibrated."
While the 3-D model doesn't yet have the exact texture or feel of a real finger, it could advance fingerprint sensing and matching technology.
"Tools like this would help improve the overall accuracy of fingerprint-matching systems, which eventually leads to better security in applications ranging from law enforcement to mobile phone unlock," Jain said.
Members of Jain's team include Sunpreet Arora, a computer science doctoral student, Kai Cao, a research associate in computer science and engineering and research collaborator Nick Paulter at the National Institute of Standards and Technology
Jain, who has a B.Tech degree from IIT Kanpur and MS and PhD degrees from Ohio State University, has six US patents on fingerprint matching and has written a number of books on biometrics and fingerprint/facial recognition.
Additionally, Jain has also received a number of prestigious awards for contributions to pattern recognition and biometrics.
SOURCE
Sunday, March 9, 2014
Usain Bolt would be able to fly – if we could get him to Saturn!
Physics students have concocted a bizarre theoretical experiment involving one of Saturn's moons, a wingsuit and the world's fastest man – Usain Bolt.
The University of Leicester undergraduates have calculated that record-breaking Bolt could fly like a bird if it was possible to transport him more than one billion kilometres to Titan and strap him into a skydiving wingsuit.
It shows that the Jamaican sprinter would be one of a handful of humans fast enough to reach the speed needed for take off on the low-gravity moon.
Flapping his arms like a giant bird, the wingsuit would allow Bolt to generate enough lift to carry him into the sky and soar majestically through the air.
The surreal theory has been postulated before, but the Leicester students are the first to apply the science.
The work is part of their final year paper for the Journal of Physics Special Topics – a peer-reviewed student journal run by the university's Department of Physics and Astronomy.
Student Hannah Lerman, 21, said: "I had seen a lot of claims online that humans would be able to fly on Titan, but no one had given the physics behind it.
"I thought it would be interesting to try it with a wingsuit – something that you actually use on Earth.
"It is a really exciting idea that someone such as Usain Bolt could actually fly unaided. It would give a whole new dimension to travelling. I am really interested in the journal side of science, and it was fascinating to see how that was run as part of this module."
Titan is Saturn's largest moon and has a dense, nitrogen-rich atmosphere with a surface pressure almost 50 per cent stronger than Earth's.
As a result, it has long been predicted that humans would be able to lift off into the moon's atmosphere if they were wearing wing-type devices on their arms.
But now, the students have shown that it would even be possible with a regular wingsuit used by skydivers here on Earth – provided you could get a fast enough run- up.
To calculate the speed needed, the group factored in:
The density of air on the surface of Titan.
The acceleration due to gravity.
An average wingsuit wing area (about 1.4 metres squared).
The ratio of the streamline path of the air above the aerofoil to that below the aerofoil.
They found that, for a normal-sized wingsuit, a run-up speed of 11 metres a second would be required.
That would be no problem for Bolt, who has gone faster than 12 metres a second.
Course tutor Dr Mervyn Roy, a lecturer in the University of Leicester's Department of Physics and Astronomy, said: "The aim is for the students to learn about peer review and scientific publishing.
"They are encouraged to be imaginative with their topics and find ways to apply basic physics to the weird, the wonderful and the everyday."
Source
The University of Leicester undergraduates have calculated that record-breaking Bolt could fly like a bird if it was possible to transport him more than one billion kilometres to Titan and strap him into a skydiving wingsuit.
It shows that the Jamaican sprinter would be one of a handful of humans fast enough to reach the speed needed for take off on the low-gravity moon.
Flapping his arms like a giant bird, the wingsuit would allow Bolt to generate enough lift to carry him into the sky and soar majestically through the air.
The surreal theory has been postulated before, but the Leicester students are the first to apply the science.
The work is part of their final year paper for the Journal of Physics Special Topics – a peer-reviewed student journal run by the university's Department of Physics and Astronomy.
Student Hannah Lerman, 21, said: "I had seen a lot of claims online that humans would be able to fly on Titan, but no one had given the physics behind it.
"I thought it would be interesting to try it with a wingsuit – something that you actually use on Earth.
"It is a really exciting idea that someone such as Usain Bolt could actually fly unaided. It would give a whole new dimension to travelling. I am really interested in the journal side of science, and it was fascinating to see how that was run as part of this module."
Titan is Saturn's largest moon and has a dense, nitrogen-rich atmosphere with a surface pressure almost 50 per cent stronger than Earth's.
As a result, it has long been predicted that humans would be able to lift off into the moon's atmosphere if they were wearing wing-type devices on their arms.
But now, the students have shown that it would even be possible with a regular wingsuit used by skydivers here on Earth – provided you could get a fast enough run- up.
To calculate the speed needed, the group factored in:
The density of air on the surface of Titan.
The acceleration due to gravity.
An average wingsuit wing area (about 1.4 metres squared).
The ratio of the streamline path of the air above the aerofoil to that below the aerofoil.
They found that, for a normal-sized wingsuit, a run-up speed of 11 metres a second would be required.
That would be no problem for Bolt, who has gone faster than 12 metres a second.
Course tutor Dr Mervyn Roy, a lecturer in the University of Leicester's Department of Physics and Astronomy, said: "The aim is for the students to learn about peer review and scientific publishing.
"They are encouraged to be imaginative with their topics and find ways to apply basic physics to the weird, the wonderful and the everyday."
Source
Friday, January 3, 2014
Saturn's Rings are 4.4 Billion Years Old
Researchers using data from Nasa's Cassini spacecraft have found that Saturn's rings formed around 4.4 billion years ago, shortly after the planet itself took shape.
The origin of Saturn's ring system remains hotly debated, with some researchers arguing that it's a relatively young structure and others holding that it coalesced long ago, at roughly the same time as the gas giant's many satellites.
The new study, using data gathered by Nasa's Saturn-orbiting Cassini spacecraft, strongly supports the latter scenario, researchers said.
Cassini's measurements suggest that "the main rings would be [extremely] old, rather than hundreds of millions of years old," said Sascha Kempf, of the University of Colorado in Boulder.
Saturn's main ring system is huge but razor-thin, measuring about 280,000 kilometres across but just 33 feet or so in the vertical direction. The rings are composed primarily of water ice, but they contain small amounts of rocky material contributed by micrometeoroid bombardment, 'LiveScience' reported.
Kempf and his colleagues used Cassini's Cosmic Dust Analyzer instrument to measure just how frequently such tiny particles cruise through the Saturn system. They found that a surprisingly small amount of dusty material comes into contact with the rings.
After measuring the low rate of dust recruitment, the team calculated that the rings have likely existed for about 4.4 billion years. "It would be consistent with an old ring system," Kempf said.
The study was presented at the annual meeting of the American Geophysical Union.
The origin of Saturn's ring system remains hotly debated, with some researchers arguing that it's a relatively young structure and others holding that it coalesced long ago, at roughly the same time as the gas giant's many satellites.
The new study, using data gathered by Nasa's Saturn-orbiting Cassini spacecraft, strongly supports the latter scenario, researchers said.
Cassini's measurements suggest that "the main rings would be [extremely] old, rather than hundreds of millions of years old," said Sascha Kempf, of the University of Colorado in Boulder.
Saturn's main ring system is huge but razor-thin, measuring about 280,000 kilometres across but just 33 feet or so in the vertical direction. The rings are composed primarily of water ice, but they contain small amounts of rocky material contributed by micrometeoroid bombardment, 'LiveScience' reported.
Kempf and his colleagues used Cassini's Cosmic Dust Analyzer instrument to measure just how frequently such tiny particles cruise through the Saturn system. They found that a surprisingly small amount of dusty material comes into contact with the rings.
After measuring the low rate of dust recruitment, the team calculated that the rings have likely existed for about 4.4 billion years. "It would be consistent with an old ring system," Kempf said.
The study was presented at the annual meeting of the American Geophysical Union.
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