On 30 Aug 2006 the Hubble Space Telescope and the Keck Observatory took images of Dysnomia's movement
Taking advantage of a rare astronomical event called an “occultation” – when an object in the foreground blocks another object from view – scientists found that the dwarf planet Eris is not larger than Pluto, as previously thought, but is essentially the same size.
According to astronomers, occultations provide the most accurate, and often the only, way to measure the shape and size of a distant Solar System body.
Discovered in 2005, Eris is the most massive known dwarf planet in the Solar System. It is orbited by one moon, Dysnomia, and is about three times further from the sun than Pluto.
As a result, Eris and its moon are believed to be among the most distant natural objects in our Solar System.
An artist's impression of the dwarf planet Eris. (Photo: Credit: ESO/L. Calçada)
The discovery of Eris led scientists to create a new class of objects called dwarf planets. That started a chain of events which eventually led to Pluto’s demotion from full-fledged planet to its current classification as a dwarf planet.
An international team of astronomers got the occultation they needed to observe Eris in November 2010. Using a number of observational tools, including the TRAPPIST (TRAnsiting Planets and PlanetesImals Small Telescope) at the La Silla Observatory in Chile, the team discovered that Eris is almost spherical in shape. They also determined Eris’ diameter to be 2,326 kilometers. Previous measurements put the dwarf planet’s diameter at around 3,000 kilometers, or approximately 25 percent larger than Pluto.
These new findings also suggest that the surface temperature for the side of Eris facing the sun is about -238 Celsius at most, with even colder temperatures on its night side. Its surface is extremely reflective, reflecting 96 percent of the light that falls on it, making it to be one of the most reflective objects in the Solar System.
Need an Inexpensive Braille Writer? There’s an App for That
Touchscreen Braille writer created by undergraduate student Adam Duran with his mentors Adrian Lew, an assistant professor of mechanical engineering, and doctoral candidate Sohan Dharmaraja from Stanford University. (Photo: Stanford School of Engineering)
A new Braille writer, created from a relatively inexpensive tablet computer, won the top award at an annual competition held every summer at Stanford University.
Adam Duran, an undergraduate student from New Mexico created the application with two mentors, Adrian Lew, an assistant professor of mechanical engineering, and Sohan Dharmaraja, a Stanford doctoral candidate studying computational mathematics.
Now in his senior year at New Mexico State University, Duran originally planned to create a character-recognition application, or “app” for a mobile device, such as a Smartphone or tablet computer. The app would make use of the tablet’s camera to take pages of Braille and convert it into readable text.
While the challenge of that project appealed to Duran and his mentors, they realized they could go even further in creating a unique device to help the visually impaired.
The groundwork for the device’s design and mission was laid even before Duran arrived at Stanford. Lew and Dharmaraja met with representatives of Stanford’s Office of Accessible Education, which helps blind and visually-impaired students make their way through the world of higher learning. Lew and Dharmaraja developed ideas from that meeting that they shared with Duran.
After sitting down and brainstorming, the three gentlemen realized that, instead of coming up with a reader, a writer would really be more useful.
A device which would help the blind with everyday writing challenges, such as sending an email or taking notes in class, was needed.
“These are real challenges the blind grapple with every day,” said Lew.
While there are devices on the market that help the blind write Braille, Duran and his mentors discovered the specialized laptops can cost more than $6,000 and tend to have limited functionality.
The three realized a regular tablet computer is a lot cheaper than the specialized devices, so they decided to develop a tablet Braille writer which comes with a touch screen for people who can’t see.
Duran and his mentors had to address a number of challenges to make such a device workable. First off, they all needed to learn Braille before they could even proceed with their work.
Next, they faced a simple logistical concern; how to replicate a typical Braille writer’s specialized keyboard – with all its unique physical characteristics – on the flat glass surface of a tablet computer. Their answer was to create a virtual keyboard on the tablet surface.
However, instead of designing one that the user’s fingertips must find, they made keys that find the fingertips. Once the user places eight typing fingertips on the tablet’s surface, the keys appear and orient themselves to the fingers. If the user pauses or becomes disoriented, the unit can be reset by taking all eight fingers off the tablet surface and then putting them back down again.
Here’s how it works; each time a user types a keystroke, the tablet vibrates and a computer voice vocalizes the letter or character that was entered. Besides typing, the tablet writer also offers access to a variety of menu options. The user drags a finger across the tablet surface for the menu items to be vocalized. Lifting the finger used to access the menu activates a menu item.
Along with being cost effective, the units are flexible and customizable. It doesn’t matter if the user’s fingers are huge or tiny, the unit automatically accommodates all users. And you can use the unit from any position; reclining, standing up or sitting. The user can even use the device while it’s hanging around the neck.
To demonstrate the device, Duran put on a blindfold, oriented his fingers with the tablet’s touch screen and typed out an email address and a simple subject line. As an encore, he typed out a well-known mathematical formula and chemical equation.
All three gentlemen are anxious to see the device refined and further developed, so it can be put into the hands of those who need it most.
Sohan Dharmaraja joins us this weekend on the radio edition of “Science World.” So if you’d like to hear more about the creation of this tablet computer Braille writer, either tune into the show (see right column for scheduled times) or check out the interview below.
>>>> Listen to the interview here
[audio://blogs.voanews.com/science-world/files/2011/10/One-On-One-Sohan-Dharmaraja-Tablet-Computer-Braile-writer.mp3|titles=One On One – Sohan Dharmaraja – Tablet Computer Braile writer]
Other stories we cover on the “Science World” radio program this week include:
Science Scanner: Depressed Teens Listen to More Heavy Metal Music
Members of heavy metal band Asphyx in concert (Photo: Hervegirod at en.wikipedia)
An ongoing study out of Australia might be of interest to all the head-banging heavy metal music fans out there.
University of Melbourne researcher Dr. Katrina McFerran finds that young people at risk of depression are more likely to listen to heavy metal music.
McFerran wanted to find out why some teenagers use heavy metal music in a negative way.
She interviewed 50 young people between the ages of 13 and 18, while also conducting a national survey of 1,000 young people. McFerran wants to use her research to develop an early intervention model which can be integrated into schools before behavioral problems occur.
“Most young people listen to a range of music in positive ways; to block out crowds, to lift their mood or to give them energy when exercising, but young people at risk of depression are more likely to be listening to music, particularly heavy metal music, in a negative way,” says McFerran.
She says someone who listens to the same heavy metal music over and over again, without listening to anything else, is attempting to isolate themselves or escape from reality. This continued behavior might signal depression, anxiety or, at worst, suicidal tendencies.
McFerran wants parents to be aware of their children’s music listening habits so they can pick up on early warning signs and take early action.
Remnants of the oldest recorded supernova, RCW 86 (Photo: NASA/ESA/JPL-Caltech/UCLA/CXC/SAO)
In what sounds like a chapter from a thrilling detective book, NASA scientists say they’ve solved a 2,000-year-old mystery.
Back in 185 A.D., Chinese astronomers noted something they called a “guest star,” which mysteriously appeared in the sky and remained there for about eight months.
Scientists in the 1960’s determined that the “guest star” observed by the ancient astronomers was actually the first supernova ever recorded.
Later research allowed scientists to gather more data from this astronomical first, now called RCW 86. They found it is a supernova remnant, which is located about 8,000 light-years away.
“It’s two to three times bigger than we would expect for a supernova that was witnessed exploding nearly 2,000 years ago. Now, we’ve been able to finally pinpoint the cause,” says Brian J. Williams, an astronomer at North Carolina State University in Raleigh and lead author of the study detailing the new findings.
What the Chinese astronomers observed so many years ago was a “Type Ia” supernova, which was created by the relatively peaceful death of a star – much like our own sun – which then shrank into a dense star called a white dwarf. It’s thought that this white dwarf, after siphoning matter or fuel from a nearby star, later blew up in a supernova.
We’ve learned, for the first time, that a white dwarf can create a cavity around it before blowing up into a Type Ia event. A cavity would explain why the remains of RCW 86 are so big. When the explosion occurred, the ejected material would have traveled, unimpeded by gas and dust, spreading out quickly.
When you think of someone who suffers from atherosclerosis, a hardening of the arteries, you most likely think of an older person. But, a study by Canada’s Heart and Stroke foundation, finds the disorder also affects a large number of young people.
“The proportion of young, apparently healthy adults who are presumably ‘the picture of health,’ who already have atherosclerosis is staggering,” says Dr. Eric Larose, an interventional cardiologist at the Institut Universitaire de Cardiologie et de Pneumologie de Québec
Atherosclerosis can eventually lead to serious problems including heart disease, stroke or even death.
The study included 168 young adults between 18 to 35 years of age – half male and half female – who had no known cardiovascular disease or risk factors.
The researchers found that, although a large proportion of their test subjects didn’t have the traditional risk factors for atherosclerosis, they did show discrete signs, such as a greater waist circumference, and visceral fat covering the internal organs within the chest and abdomen.
The researchers say the lesson this study teaches is that beyond simple weight and BMI, measures of fat hidden within are greater predictors of atherosclerosis. Those with a greater amount of visceral fat will have greater atherosclerosis, even if they are young and apparently healthy – and could benefit from preventative lifestyle measures.
The researchers are looking at carbon nanotubes as a key component in developing this salmonella sensing tool. Carbon nanotubes – arrangements of carbon atoms in a cylindrical shape – are known for their unique atomic architecture, which gives them extraordinary electrical, mechanical and physical properties.
When combined with biological molecules, such as antibodies, carbon nanotubes have the potential to perform a wide range of new and useful functions such as what will be required by this salmonella detection device.
Further research is needed before a carbon nanotube biosensor for salmonella is available commercially. But the research results may help bring the concept a step closer to reality, eventually playing an important role in controlling food poisoning outbreaks.
Researchers came to that conclusion after studying the residue found on ancient cooking vessels.
In analyzing 133 ceramic vessels from the western Baltic regions of northern Europe, they tried to determine whether the origin of the food residue came from land, sea or freshwater organisms.
The ancient ceramic pottery from 15 sites dated to around 4,000 BC, about the same time the first evidence of domesticated animals and plants was found in the region.
The researchers found that, despite the onset and rapid move to farming and domestication, humans living in coastal areas still ate a diet rich in fish and other aquatic-based foods.
The cooking pots from these regions contained food residues abundant with a form of carbon commonly found in marine organisms.
Perhaps that isn’t surprising. However, what is interesting is that fish was also a popular food staple for those living further inland, too. Almost one third of the pottery found at sites further from the coast contained residue from aquatic organisms, probably freshwater fish.
“This research provides clear evidence people across the western Baltic continued to exploit marine and freshwater resources despite the arrival of domesticated animals and plants,” says study lead author Dr. Oliver Craig of the Department of Archaeology at York. “Although farming was introduced rapidly across this region, it may not have caused such a dramatic shift from hunter-gatherer life as we previously thought.”
The researchers say this is the first large-scale study to combine a wide range of molecular evidence and single-compound isotope data, which indicates whether the material processed in ancient ceramics was of terrestrial, marine and freshwater origin. They believe their work provides a template for future investigations into how people used similar cooking vessels in the past.
Faster than the Speed of Light and the Search for Higgs Boson
CERN'S Globe of Science and Innovation at night (Photo: CERN)
The work that’s being done at the European Organization for Nuclear Research (CERN) Laboratory in Europe has generated news headlines for years. Recently though, since the Large Hadron Collider (the world’s largest and highest-energy particle accelerator) went online, we’ve been hearing even more about the ambitious activities being undertaken by this scientific organization, their affiliates and partners.
Within the last month, one CERN experiment in particular, OPERA, stunned the scientific community with its announcement that they discovered sub-atomic particles called neutrinos traveling faster than the speed of light, which should be impossible since Albert Einstein’s theory of relativity says nothing can go faster than the speed of light.
Days later CERN’s director general, Rolf-Dieter Heuer speaking at a press conference with the heads of two other world renowned physics laboratories declared that “I think by this time next year I will be able to bring you either the Higgs boson or the message that it doesn’t exist.” The Higgs boson is a theoretical
CERN Control Centre (Photo: CERN)
sub-atomic particle that physicists say should help explain the origins of mass and why matter has mass and is considered to be a key component of “The Standard Model of particle physics.” Dr. Heuer’s Large Hadron Collider has been a key tool in the search for this elusive and important piece of the physics puzzle.
With all of this talk about CERN, the LHC, and the recent challenge to Einstein’s theory of relativity – we wanted to get a physicist’s unique perspective of it all, so we got in touch with Dr. Pierre Savard from the University of Toronto, a physicist who not only teaches physics, but is actually doing research work with CERN and its Large Hadron Collider.
On the OPERA experiment: Neutrinos found traveling faster than the speed of light
View of the OPERA detector (on the CNGS facility) (Photo: CERN)
“People, in general, are skeptical for a variety of reasons”, says Savard. He compared it to the arrival of Einstein’s theories about a hundred years ago. While Einstein’s theories kind of supplanted Newton’s Laws of Motion, they didn’t invalidate them, unlike OPERA’s findings, which if proven true, would invalidate Einstein’s theory that nothing travels faster than light.
The speed of neutrinos has been measured in the past. Dr. Savard points to a supernova explosion in 1987 when scientists found that the neutrinos did get here a little bit before light, but that didn’t mean that they were going faster than light, it turns out that the neutrinos were emitted before light was emitted and the difference between the arrival of the neutrino signal and the light signal was within a few hours of each other. Now, if you applied the results of OPERA to those neutrinos from the supernova, Dr. Savard says that “they would have to come in years before.” Dr. Savard also notes that some objections to OPERA’s findings were raised based on existing theories, “if a particle goes faster than light then we expect that that particle will emit some radiation and therefore lose energy.”
Before the findings of the OPERA experiment are verified or invalidated, the energies that were produced by CERN will need to be reproduced, measurements of those energies will then need to be taken, and then scientists must check and verify all related data and systematics of the experiment before it can be said whether or not this controversial finding is real or not.
On the search for the Higgs boson
One of two large general-purpose particle physics detectors built on the proton-proton Large Hadron Collider (LHC) at CERN (Photo: CERN)
Dr. Savard is involved in CERN’s search for the Higgs boson and says that they are “pretty close” to either finding it or showing that it doesn’t even exist. He says that there are many experiments and many people actively working on finding what some consider the Holy Grail of particle physics and that CERN’s Large Hadron Collider has delivered a lot of data on this project. The Standard Model of particle physics makes very precise predictions as to how it should be produced, how it should behave and how scientists should look for it. Because of these precise predictions, Dr. Savard says, “we should be able to find it, probably next year or two, or exclude it.”
If the Higgs-boson is found, Dr. Savard predicts that it will not only be a significant scientific breakthrough in physics, but also in terms of cosmology, in terms of the one billionth of a second when the Higgs boson turned on very early in creation of the universe. Dr. Savard cautions that if they do indeed find something, scientists will really need to check that it is indeed the particle that’s predicted by the standard model and not some other variance, or a particle that may be a little different. Most likely this process would take a few years after its discovery to confirm its validity.
On the other hand if scientists find that the Higgs boson is just a mirage and that it doesn’t exist, Dr. Savard says that this would be a result that a lot of people would like and that it would be quite exciting because after over some forty years of searching for Higgs boson it would give scientists opportunities to search for something new and pursue a brand new explanation for their theories. According to the (standard model) theory, says Dr. Savard, “If the Higgs boson is not there, there has to be something in the range that is probed by the Large Hadron Collider that sort of compensates for this particle.”
Dr. Pierre Savard joins us this weekend on the radio edition of Science World, so if you’d like to hear more of his thoughts and insights either tune into the show or check out the interview below.
>>>> Listen to the interview here
[audio://blogs.voanews.com/science-world/files/2011/10/Dr.-Pierre-Savard-Web-Intvw.mp3|titles=Dr. Pierre Savard – Web Intvw]
Other stories we cover on the “Science World” radio program this week include:
Science Scanner: Russian Space Agency Blamed for Recent Accidents
A Russian Proton booster rocket blasts off from Baikonur cosmodrome in Kazakhstan (Photo: AP)
The Russian Prosecutor General’s office is pressing for disciplinary measures and fines after finding the state-run Roskosmos space agency to blame for two recent high-profile – and highly embarrassing – incidents.
The accidents forced Roskosmos to temporarily ground its Soyuz and Proton-M rockets, threatening the future of the International Space Station (ISS). Following the end of NASA’s space shuttle program, the Russian rockets are the only way to send supplies and ferry crew members back and forth from the space station. As a result, NASA considered abandoning the space station for the first time in 10 years.
The Russian Prosecutor General’s office singled out the agency’s executive for separate blame for “a lack of proper control on the part of Roskosmos officials over the adoption of corresponding decisions.”
Acknowledging the criticism, Roskosmos said it is severely underfunded and unable to compete with firms from Western countries in recruiting and retaining talented employees.
On a postive note, Roskosmos did manage to successfully test launch a Soyuz model on Oct. 3 and is going forward with plans to send the next crew to the ISS on Nov. 14.
Progress reported in the development of a malaria vaccine
A promising new malaria vaccine appears to reduce the risk of children contracting the disease by 56 percent.
The first results of the large-scale Phase III trial of the vaccine, RTS,S, were published in the online edition of the New England Journal of Medicine.
The trial is being conducted at 11 sites in seven sub-Saharan Africa countries. So far, it shows that three doses of RTS,S reduces the risk of children experiencing clinical malaria by 56 percent and severe malaria by 47 percent. These first Phase III results are in line with those from previous Phase II studies.
The World Health Organization has said it could recommend using the RTS,S malaria vaccine in 2015. The recommendation would pave the way for African nations to implement the vaccine through large-scale basis national immunization programs.
Climate change appears to cause Earth’s species to shrink
Has the lynx been shrinking in size? If so, is global climate change to blame? (Photo: dogrando via flickr)
Many of Earth’s species appear to be shrinking in size, according to a new study published in the journal Nature Climate Change.
But other experts are already expressing their doubts about that.
The study, which is based on a review of previous studies, found that 38 of 85 animal and plant species have shown a documented reduction in size over decades.
The species that are getting physically smaller, according to the study, include cotton, corn, strawberries, bay scallops, shrimp, crayfish, carp, Atlantic salmon, herring, frogs, toads, iguanas, hooded robins, red-billed gulls, California squirrels, lynx, wood rats and a type of Scottish sheep, which was found to be five percent smaller than in 1985.
Although the study’s authors think the shrinkage is probably due to global warming, other experts say that that conclusion goes too far in blaming climate change for what may be natural changes.
Study co-author Jennifer Sheridan, a biology researcher from the University of Alabama, says, “There is a trend in a number of organisms across the board, from plants to big vertebrates, getting smaller. The theory is, as things get warmer, they don’t need to grow as large.”
But Yoram Yom-Tov – a zoologist at Tel Aviv University who doesn’t think global warming is completely to blame – says there’s no need for alarm. “Changes in body size are a normal phenomenon.”
In the opinion of Terry Root, a biologist at Stanford and an expert in climate change, the study’s conclusions “seem kind of far-fetched.”
In last week’s Science Scanner, we shared how lack of sleep during adolescence could have a lasting impact on how the brain is wired. Now we get word of a study that shows a person’s intelligence quotient (IQ) can significantly rise or fall during the teenage years.
It’s the first time research has shown that our IQ is not constant.
Thirty-three healthy adolescents, between 12 and 16 years old, were tested by the research team in 2004. The teens were tested again four years later, when they were between 15 and 20 years old. Both times, researchers took structural brain scans of their subjects using magnetic resonance imaging (MRI).
They found significant changes in the IQ scores from 2004 and 2008. Some of the test subjects improved their performance by as much as 20 points on the standardized IQ scale. In other cases, however, performance fell by a similar amount. The researchers analyzed the test subjects’ MRI scans to see if there were any correlating changes in the structure of their brains.
They did find some. They discovered that an increase in a subject’s verbal IQ score also resulted in an increase in the density of the nerve cells where processing takes place, an area of the left motor cortex of the brain which is activated when we talk.
An increase in the non-verbal IQ score showed a hike in the density of gray matter in the anterior cerebellum, which is associated with hand movement. However, an increase in verbal IQ didn’t necessarily translate into an increase in non-verbal IQ, too.
According to the study’s authors, this indicates that an adolescent’s intelligence is still developing and that poor IQ test scores at an early stage of this development could be somewhat deceptive, since IQ could change significantly in the next few years.
Scripps Oceanography scientists will use the surfboard-sized Wave Glider to relay real-time seismic data. (Photo: Liquid Robotics)
California scientists are developing a cutting-edge, deep-ocean seismic system which will give them more information about earthquakes and tsunamis across the globe.
The team from the Scripps Institution of Oceanography will develop a potentially transformative system for deploying seafloor seismometers, which will gather vital data – in real-time – for applications ranging from earthquake monitoring, Earth structure and dynamics to tsunami warning systems.
According to the team leader, geophysicist Jonathan Berger, there are no current deep ocean seismic systems capable of sending crucial data back to shore in real time. Right now, the systems deployed to the bottom of the ocean record data for several months before being retrieved for analysis and study.
Data from ocean bottom seismometers, from Scripps Institution of Oceanography, will be integrated into the Project IDA global seismographic network. (Scripps Institution of Oceanography, UC San Diego)
To determine the epicenter of an earthquake, its size and whether or not a tsunami is being generated, Berger says data must be available in real time to be useful.
“When you have a large earthquake, it’s important to quickly estimate the parameters of where it was and how big the seafloor displacement was,” says John Orcutt, one of the team’s co-principal investigators. “In order to do this, you need improved coverage in the ocean. During the recent devastating Japanese earthquake, there were lots of places where there was no coverage, so this effort improves upon that.”
A device called the Wave Glider is an example of the new cutting-edge technology being utilized. Developed by a company called Liquid Robotics, the Wave Glider is an eco-friendly, surfboard-sized, autonomous, unmanned vessel powered by the ocean’s wave energy and solar power.
Data transmission path for sending real-time seismic data from the seafloor to the ocean surface to shore via satellite. (Scripps Institution of Oceanography, UC San Diego)
It will tow an ocean bottom seismic device to a pre-determined location to be deployed, free floating down to its operating location.
The Wave Glider will circle around above the seismic device on the ocean’s surface, receiving data transmitted via an acoustic modem. The Wave Glider will transmit the data is receives to a shore station via satellite.
The data will be integrated into the global seismographic network of broadband and very long period seismometers called “Project IDA” (International Deployment of Accelerometers).
The data coordinated through this system has helped scientists better understand earthquakes and Earth’s interior structure for decades.
Berger’s team expects to have the system developed, designed, tested and ready for replication and deployment in about two years.
Dr. Jonathan Berger joins us this weekend on the “Science World” radio program to talk more about how this new, cutting-edge technology will provide the latest, most accurate seismic data possible.
>>>> Listen to the interview here…
[audio://blogs.voanews.com/science-world/files/2011/10/One-On-One-Dr.-Jonathan-Berger.mp3|titles=One On One – Dr. Jonathan Berger]
Other stories we cover on the “Science World” radio program this week include:
Science Scanner: What Triggers Devastating Supervolcanoes
The Mt. St. Helens eruption of May 18, 1980, sent volcanic ash, steam, water, and debris to a height of 60,000 feet. About two-thirds of a cubic mile of material was ejected. In comparison, the Toba super eruption, one of the Earth's largest known eruptions, spewed 1,000 times more material. (Washington State Department of Natural Resources)
A volcanic super eruption, which occurs about every 100,000 years, is a cataclysmic natural event, blowing out an incredible amount of debris and ash, devastating the environment and disrupting the world’s climate for years, possibly causing mass extinctions.
While scientists continuously monitor several super volcanoes around the world, they don’t know what actually triggers these violent explosions. Now, a new model of volcanic super eruptions shows these massive eruptions could be caused by a combination of magma chamber geometry and temperature.
Researchers at Oregon State University say the creation of a halo of flexible rock, which forms around the magma chamber, allows the pressure – built up over tens of thousands of years – to raise the roof above the magma chamber. Eventually faults from above trigger the collapse of the caldera, which leads to its subsequent eruption.
“You can compare it to cracks forming on the top of baking bread as it expands, as the magma chamber pressurizes at depth, cracks form at the surface to accommodate the doming and expansion,” says lead author Patricia Gregg, a post-doctoral researcher. “Eventually, the cracks grow in size and propagate downward toward the magma chamber.”
Findings of this research were presented at the annual meeting of the Geological Society of America in Minneapolis, Minn.
Officials from three of the world’s major physics labs express doubt about recent findings by European scientists who claim to have recorded subatomic particles moving faster than the speed of light.
Lack of sleep during adolescence could lead to more than slow-moving, sleepy teens, it could also have a lasting impact on how the brain is wired.
We already know that adolescence is a crucial and sensitive period of development when the brain changes dramatically. During a person’s early teen years, the brain undergoes a massive rewiring of nerve circuits.
Experimenting with adolescent mice, researchers at the University of Wisconsin-Madison found that short-term sleep restriction in their test subjects prevented the balanced growth and depletion of brain synapses, which are the connections between nerve cells where communication occurs.
The researchers are now looking into what happens to the young brain when there is a chronic sleep restriction, a condition many adolescents often experience.
Study leader Dr. Chiara Cirelli says she can’t predict the outcome of the studies which are already under way. “It could be that the changes are benign, temporary and reversible. Or there could be lasting consequences for brain maturation and functioning.”
Artist rendition of Minvera (University of Tennessee, Knoxville)
Most of us know that a number of planets have one or more moons orbiting them, but it might surprise you to learn that some asteroids have them, too. In fact, Joshua Emery at the University of Tennessee, Knoxville says about 20 percent of asteroids do.
Emery, a member of an international team planetary astronomers, focused his research on the triple asteroid Minerva, located in the main-asteroid-belt, which contains most of our solar system’s asteroids. Minverva is known to possess two moons.
“Minerva was thought to be a pretty typical, unremarkable asteroid until we discovered its two moons,” Emery says. “Now, interest in this system has grown. And through a lot of new observations, from both ground-based and space-based telescopes, we have developed a much more detailed understanding of Minerva and its moons.”
Emery and his team believe the discovery of moons around asteroids is important because it can provide clues to the asteroid’s formation.
“All other large main-belt asteroids with one or more moons are very porous,” says Emery. “Such high porosity strongly suggests that they are piles of rubble held together by gravity rather than solid rocks.”
The results of the group’s findings were released at the EPSC-DPS meeting in Nantes, France.
The leaner mouse with functional brown fat (left) dissipates considerable amounts of energy as heat. The orexin-deficient mouse (right) stores energy as fat instead of burning it. (Image by Peter Allen, UCSB)
An injection of a hormone produced naturally in the brain might help a person lose weight, without having to cut down on what they eat.
The hormone – orexin – appears to trigger so-called “good” fat to battle “bad” fat.
The fat we typically think of as body fat is called white fat. But we also have another form of fat known as brown fat and, unlike white fat, brown fat does more than just store fat. According to researchers, it actually burns fat.
Brown fat is full of blood vessels and mitochondria, which is why it’s brown. This fat tissue is apparently very good at turning our calories into energy.
The researchers discovered that orexin activates calorie-burning brown fat in mice and that a deficiency of this hormone could be associated with obesity.
To investigate further, they acquired mice which were genetically engineered to lack orexin. These mice weighed more than their non-engineered friends even though they actually ate less, which suggests overconsumption was not the cause their obesity.
The researchers found that these orexin-deficient mice, when fed a high-fat diet, were unable to properly convert the extra calories into heat the way normal mice do. Instead, that energy wound up being stored as fat.
Probing further into the mice’s brown fat, the team discovered that brown fat in the orexin-free mice didn’t develop properly at the embryonic stage, and that this shortage had lasting effects on the creatures’ energy expenditure and weight, even in adulthood.
Furthermore, once the genetically-engineered mice were given some orexin, their offspring’s brown fat developed properly before birth and continued to be active into adulthood.
The team also found that adding orexin to stem cells in a laboratory dish caused them to specialize into brown fat cells, which created even more of a fat-burning engine.
“Without orexin, the mice are permanently programmed to be obese,” says Dr. Devanjan Sikder, senior study author. “With it, brown fat is activated and they burn more calories.”
Further study on mice shows that diet dependent obesity – the most common form of obesity – can be resolved by an injection of orexin, without having to reduce calorie intake.
While most current weight loss products tend to be aimed at reducing a person’s appetite, the researchers believe a therapy based on orexin could launch a new class of fat-fighting drugs.
“This is very exciting and illustrates a shift in paradigm of anti-obesity therapeutics,” says Sikder.
Encouraged by the findings, the researchers look forward to their next step – clinical trials.
Quasicrystals are unusual materials which have some of the properties of a regular crystal, but have a more elaborate and complex structure at the atomic level. This unique material does not conduct heat or electricity well and, because of this, the quasicrystals can be used in thermoelectric materials, which converts heat into electricity and vice versa.
The Nobel prizes for physics and physiology or medicine were also announced earlier this week.
By studying distant supernovae, or exploding stars, the three physicists discovered that our universe continues to expand at an accelerating rate, even after more than 14 billion years since the Big Bang.
NASA satellite data reveals how this year’s minimum sea ice extent, reached on Sept. 9 as depicted here, declined to a level far smaller than the 30-year average (in yellow), opening up Northwest Passage shipping lanes (in red). (Graphic: NASA Goddard’s Scientific Visualization Studio)
Arctic sea ice continues to decline; the summertime sea ice cover narrowly avoided a new record low, which was set back in 2007.
The Arctic ice cap grows each winter as the sun sets for several months, then shrinks each summer as the sun rises higher in the northern sky. The Arctic sea ice reaches its annual minimum extent each year in September.
NASA monitors and studies the changing sea ice conditions in both the Arctic and Antarctic regions with a variety of spaceborne and airborne research capabilities.
Joey Comiso, a senior scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md., says that not only is the sea ice declining, but the pace of the decline is also much more drastic.
Climate models constructed by researchers suggest the Arctic could lose almost all of its summer ice cover by 2100. However, they also found that that the ice extent has declined faster in recent years than their models had predicted.
Green tea has become a popular beverage in recent years, most likely because of its many health benefits. Now food scientists at Penn State University in State College, Penn., have found another reason to drink the brew; it may slow down weight gain and serve as another tool in the fight against obesity.
Researchers fed obese mice Epigallocatechin-3-gallate (EGCG), a compound found in green tea, along with a high-fat diet. They found that the mice gained weight at a significantly slower rate than the control group mice, which didn’t get the green tea supplement
In addition to gaining weight at a slower rate, says Joshua Lambert, an assistant professor of food science in agricultural sciences at Penn State, the mice fed the green tea supplement showed a nearly 30 percent increase in fecal lipids, which suggests that the EGCG was also limiting fat absorption.
The researchers released their findings in the current online edition of the journal “Obesity.”
A bluegill fish (Photo: Tom Tetzner – U. S. Fish and Wildlife Service, Northeast Region
A fish’s personality could determine how likely it is to be caught or captured, according to Canadian researchers.
The Queen’s University in Ontario found that anglers who fished near rocky outcrops or in areas of water with submerged vegetation seemed more likely to catch timid fish who prefer safe, hidden habitats, while those fishing in open water were more likely to reel in bolder fish.
The researchers examined the personalities of bluegill sunfish which were caught using two different capture techniques; angling, which is the traditional hook attached to a fishing line; and a method called beach seining, which involves dragging a long net through water to surround and ensnare fish.
Fish caught with the angling technique appeared to be more timid than fish captured by the beach seining method.
According to the research team, the differences they found in personalities of fish could have significant evolutionary and ecological consequences for affected fish populations, as well as for the quality of fisheries.
