The Photovoltaic Retinal Prothesis system (Graphic: Palanker Lab at Stanford University)

A new prosthetic retina could restore eyesight to millions of people suffering from a common cause of blindness – age-related macular degeneration (AMD).

Usually affecting people over 50, AMD causes a loss of vision in the center of the visual field (the macula, or macula lutea) due to damage to the retina.  This condition can occur in “dry” – central geographic atrophy – and “wet” – neovascular or exudative forms.

For those afflicted with AMD, it can be difficult or even impossible to read or recognize faces.  However, in most cases, sufferers retain enough peripheral vision to allow for other activities of daily life.

AMD ranks third worldwide as a cause of blindness, behind cataract and glaucoma, and is the primary cause of sight loss  in industrialized countries, according to the World Health Organization (WHO).

“The prosthetic retina we are developing has been partly inspired by cochlear implants for the ear but with a camera instead of a microphone and, where many cochlear implants have a few channels, we are designing the retina to deal with millions of light-sensitive nerve cells and sensory outputs,” said Keith Mathieson, one of the team’s lead researchers.

The researchers at Stanford University in California hope to make their Photovoltaic Retinal Prosthesis device much simpler in design and operation than existing similar units.

A scene as it might be viewed by a person with age-related macular degeneration. (Image: National Eye Institute, National Institutes of Health)

While AMD attacks the eye’s photoreceptors, which are its image-capturing cells, the prosthetic retina works by electrically stimulating neurons in the retina that have been left relatively untouched by the ravages of the disease.

This new device uses “video goggles” to transport energy and images directly to the eye.  The unit operates remotely by pulsed near infrared light that stimulates the retina and produces visual perception in the patient.

Since the device requires no wires, surgical implantation will be simpler than many current prosthetic retinas, which are driven by coils and often require complex surgery to be implanted.

“The current implants are very bulky, and the surgery to place the intraocular wiring for receiving, processing and power is difficult,” said Stanford’s Daniel Palanker, who led the research. “With our device, the surgeon needs only to create a small pocket beneath the retina and then slip the photovoltaic cells inside it.”

Initial tests of the Photovoltaic Retinal Prothesis have been encouraging, according to an article published in  Nature Photonics, and the device is now being further developed.

Exercise can curb muscle breakdown in heart failure patients (Photo: National Institutes of Health)

We all know physical activity is good for us, and now new research suggests regular exercise can also help the aging and those suffering from heart failure.

In fact, researchers say, maintaining a regular physical workout can offset the breakdown of muscle, increase strength, reduce inflammation and condition the body to handle even more exercise.

And, the good news is, it doesn’t matter how old the patient is.

“Many physicians – and insurance companies – still believe that cardiac rehabilitation does not really help in old age. This study clearly falsifies this belief,” said Stephan Gielen, M.D., the study’s lead co-author and deputy director of Cardiology at the University Hospital, Martin-Luther-University of Halle, Germany.

Heart failure, a potentially deadly condition, occurs when the heart can’t keep up with its workload.  If the heart muscle cannot pump enough blood, it cannot meet the body’s needs for blood and oxygen.

As a result, those with heart-failure get tired easily and can have shortness of breath.  Activities most of us take for granted, such as walking, climbing stairs or other actions that require even mild exertion, can become very difficult for those with this condition.

According to the American Heart Association, about 5,700,000 Americans age 20 and older have heart failure.

For their study,  researchers recruited 60 heart-failure patients and 60 healthy volunteers in 2005 and 2008.   Half of each of these two groups consisted of people 55 years and younger, while the other half was 65 years and older, allowing for an average age difference of 20 years between the groups.

Even a casual walk can fatigue someone with heart failure (Photo: Michael Cohen via Flickr/Creative Commons)

Half of the people in each age group were assigned, at random, to four weeks of supervised aerobic training, while the other half was told not to exercise during that time.

Before each group began their assigned schedule of exercises, or non-exercise, the researchers took biopsies from the thigh muscles of all the study subjects.  The muscle samples were taken again after the four-week test period.

Those assigned to the exercise group had four 20-minute periods of aerobic exercise every day for five days a week and also participated in one weekly 60-minute group exercise session.

The leg muscle strength of those in the exercise group was measured before they began their exercise program and once it concluded four weeks later.

The researchers found that all who exercised had increased their muscle force endurance and oxygen uptake – a measure of how much oxygen a body is consuming at any given time.  The heart failure patients 55 and under had increased their peak oxygen uptake by 25 percent, while those 65 and over increased it by 27 percent.  Both the younger and older groups of heart failure patients showed increased muscle strength after the four-week exercise program, but their muscle size was unaffected.

“Exercise switches off the muscle-wasting pathways and switches on pathways involved in muscle growth, counteracting muscle loss and exercise intolerance in heart failure patients,” Gielen said.

The study authors believe their research could lead to possible treatment of the muscle breakdown and wasting associated with heart failure.

Dr. Gielen joins us with more insight on this week’s radio edition of “Science World.”  See right column for scheduled times, or check out the interview with Dr. Gielen below.

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Other stories we cover on the “Science World” radio program this week include:

• Concern grows over rise of drug-resistant bacteria in India
• Internet Week in New York City draws a crowd
• Frog expert identifies poisonous frogs by licking them
• WHO study: non-communicable diseases cause most deaths worldwide
• Pacific Islands aim for energy self-sufficiency

A woman uses the BrainGate system to mentally control a robotic arm and reach for a drink. (Photo: The BrainGate Collaboration)

Almost 15 years after being paralyzed by a stroke, a 58-year-old woman was able to reach for, pick up and take a sip of a drink, by using her thoughts to operate a robotic arm.  Up until then, the woman had depended upon caregivers to do this for her.

As technology continues to meld man with machine, BrainGate – a multidisciplinary team of researchers – has spent years developing these human/robotic-type systems.

While the team’s innovations show significant promise for people with brain injuries and disorders, the technology is years away from practical use.

The research team has recently been developing and testing an element of their system called the BrainGate neural interface system.  It’s a brain-computer interface (BCI) device which allows the brain to control various robotic elements and other similar pieces of equipment.

A new report, published in Nature, examines clinical trials of the device, which focus on the system’s durability and its potential for long-term use.

Part of the BrainGate system is implanted in the brain to capture the neural signals that control intentional movement.

“Years after the onset of paralysis, we found that it was still possible to record brain signals that carry multi-dimensional information about movement and that those signals could be used to move an external device,” said Dr. Leigh Hochberg, the clinical trials lead investigator.

The group’s neural interface system has a baby aspirin-sized sensor that monitors brain signals. The sensor is implanted into the motor cortex, the part of the brain that controls movement.  The brain signals picked up by the sensor are then fed into a computer system outfitted with specially-designed software and hardware which turn the brain signals into digital commands, which in turn drive external devices such as robotics systems.

The latest trial research studied two stroke patients, the 58-year-old woman and a 66-year-old man.  Both study subjects were unable to speak or move their limbs because of brainstem strokes they suffered years ago.  During the experiment, both were taught to perform complex tasks with a robotic arm by imagining the movements of their own arms and hands.

Dr. John Donoghue, who leads the development of BrainGate technology, is especially encouraged by the woman’s ability to use the BrainGate neural interface system because her stroke happened nearly 15 years ago and her sensor was implanted more than five years ago.

The research team was concerned neurons in the motor cortex might die or stop generating meaningful signals after years of disuse and that, after years since implantation, the sensor might break down and become less effective at enabling complex motor functions

The BrainGate research team’s ideal system would be wireless, fully automated and able to provide decades of stable operation. However, to achieve that goal, they must continue trial studies and test the technology in more individuals.

UItimately, BrainGate hopes to develop a system which reconnects the brains of those suffering from paralysis directly to their paralyzed limbs, rather than with robotic ones.

Screen-shot Map of Life (Image: Yale University)

A new website, built on a Google Maps platform, allows anyone with an Internet connection to map the known global distribution of nearly all of Earth’s species, including mammals, birds, amphibians and reptiles, as well as the fresh water fish of North America.

This initial version of  “Map of Life” shows how all of Earth’s animals are geographically distributed throughout the world.

“It is the where and the when of a species,” says Walter Jetz, associate professor of ecology and evolutionary biology at Yale University, who helped lead the project. “It puts at your fingertips the geographic diversity of life. Ultimately, the hope is for this literally to include hundreds of thousands of animals and plants, and show how much or indeed how little we know of their whereabouts.”

A joint effort with the University of Colorado and the Calgary Zoological Society, the ongoing project is outlined in “Trends in Ecology and Evolution”.

The team anticipates “Map of Life” will be a useful tool for a number of people, including professional scientists, wildlife and land managers, ecological and conservation organizations, as well as interested members of the general public.

(Map of Life demo)

Data for the project includes contributions from various museums; local and regional checklists; and observations recorded by both professional and amateur scientists.

The map is expected to grow as additional data is continuously added by both professionals and amateurs, allowing researchers to identify and fill knowledge gaps, while at the same time offering a unique tool which can be used to detect change over a period of time.

Just how in-depth and extensive the map will be depends upon the continual input, support and participation by others in the scientific community.  In future versions, the mapping tool will offer various mechanisms for users to supply new or missing information.

Fundamentally, the map is, “an infrastructure, something to help us all collaborate, improve, share, and understand the still extremely limited geographic knowledge about biodiversity,” Jetz says.

Little girl snacks on cotton candy (Photo: AP Photo/Carolyn Kaster)

Attitudes, relationships, intentions and personal behavior control are all factors which influence whether children reach for junk food rather than opting for healthy snacks, such as fruit and vegetables.

A University of Cincinnati study finds intentions are a major factor behind a child’s snack choices. This is driven by several variables, such as the child’s attitude toward eating healthy or unhealthy foods, as well as the social or peer pressure the child feels.

While we all love to snack from time to time, we don’t always go for the healthier choice, opting instead for junk food, which is  high in calories but low in nutritional value.

Children are no different when it comes to snacking, but as awareness of childhood obesity continues to rise, researchers and public health officials are increasing their scrutiny of children’s eating habits, including what they choose to eat as snacks.  Zeroing in on the problem of obesity in children is an important public health concern and could help prevent future health threats such as diabetes and heart disease.

The study points to the strong influence of parents, teachers and other adults kids know and trust.  If a parent or teacher has good snacking or eating habits, this can influence what the child eats well, too.

The amount of control children feel they have over snacking is another factor influencing snack choice; in other words, if they are given the freedom to choose their own snacks rather than having them already selected for them.

Published in the International Quarterly of Community Health Education, the study looked at the eating and snacking behaviors of 167 fourth- and fifth-grade elementary schoolchildren in the Cincinnati, Ohio, area over a 24-hour period.

The study did find that snacking was a major part of the children’s caloric intake, about 300 calories a day from foods like chips, candy and cookies.  These so-called high-calorie, low-nutrition foods made up around 17 percent of the kids’ daily caloric needs.  Only 45 calories of the study group’s daily intake came from healthy snacks like fruits and vegetables.

Healthy choice - boy eating an apple (Photo: AP Photo/Jacqueline Arzt)

Researchers also examined whether children thought selecting lower-calorie snacks over the high-calorie versions was a good idea; how confident there were in knowing how to pick the lower-calorie snack foods; and whether they were influenced or felt pressure from their parents, teachers or friends in picking the lower-calorie snacks.

The demographics of the children in the study group were varied and included a mix of boys and girls, Caucasians, African-Americans, Hispanics and Asian-Americans.

There are also differences in snack choices along the lines of gender and ethnicity.  Girls in the study tended to eat more of the high-calorie snacks, taking in an average of 348.3 calories a day, while boys consumed around 238.8 calories each day.

African-American children ate the smallest amount of high-calorie snacks, at 221.6 calories a day. Hispanic children consumed 297.6 snack calories daily, followed by Caucasian children who ate 282.3 calories a day. Asian-American children who took in about 280.8 calories a day.

Among the ethnic groups measured, the study also finds that both Hispanic and Asian-American children consume more of the healthier snacks, such as fruit and vegetables, than both Caucasian and African-American children.

The study’s authors say their research suggests more care and concern should be given to what foods children choose for their snacks, because they’re relatively cheap and easy for children to buy.

You can listen to what Dr. Paul Branscum, one of the study’s authors, says about the study, what it revealed and how important it is to the future health of our children to pay attention to their choices of snack foods and encourage healthier eating habits.

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It what it calls an historic step in the search for signs of life on other planets, NASA says its astronomers have detected light coming from a “super-Earth” planet 41 light years away.

It marks the first time direct light from a rocky super-Earth planet has been seen, researchers said.

The planet, called 55 Cancri e, is 25 times closer to its star (55 Cancri) as Mercury is to the Sun. New data from the Spitzer Space Telescope indicates the planet is about twice as big and eight times as massive as Earth.  The side of it that faces the sun is more than a scorching 2,000 Kelvin (1,727 degrees Celsius), hot enough to melt metal.  And, one year on 55 Cancri e lasts a mere 18 Earth minutes.

According to NASA, the Spitzer Space Telescope and others have been able to study this planet in the past by analyzing how the light from it changed as the planet passed in front of the star.  With this new discovery, Spitzer was able to actually measure just how much infrared light comes from the planet itself.

New data from the Spitzer shows that 55 Cancri e is a “water world,”  with a rocky core that’s surrounded by water which is in a “supercritical state,” meaning the water is in both liquid and gas forms, and is capped with a blanket of steam.

NASA says these new findings are concurrent with prior theories regarding the makeup of the planet

“It could be very similar to Neptune, if you pulled Neptune in toward our sun and watched its atmosphere boil away,” said principal investigator, Michaël Gillon of Université de Liège in Belgium.

>>> Read more…

Addicted to Facebook

(Image: AP Photo/Craig Ruttle, file)

Younger users are much more likely to become addicted to Facebook than older people, according to a new worldwide study of people who use the social networking website.

With more than 800 million active members, Facebook has become a worldwide phenomenon.  Many Facebook members find themselves checking the website numerous times of day to get the latest info on their friends and their activities.

Dr. Cecilie Schou Andreassen from Norway’s University of Bergen headed the “Facebook Addiction” study.  Her team also developed the Bergen Facebook Addiction Scale to measure dependency.

The team found Facebook addiction happens much more to younger users than those who are older, and that anxious and socially insecure people tend to use the website more.  Andreassen believes this is because those who are anxious or insecure find it easier to communicate with others through Facebook and other social media rather than through face-to-face conversations.

According to the study, organized and more ambitious people aren’t as likely to become as addicted to Facebook, although they often use it as an important professional networking tool.

The study also found women are more at risk of developing Facebook addiction than men probably,  according to Andreassen, because of the social nature of Facebook.

Andreassen’s Bergen Facebook Addiction Scale lists six warning signs.

• You spend a lot of time thinking about Facebook or planned use of Facebook
• You feel an urge to use Facebook more and more
• You use Facebook in order to forget about personal problems
• You have tried to cut down on the use of Facebook without success
• You become restless or troubled if you are prohibited from using Facebook
• You use Facebook so much that it has had a negative impact on your job/studies

>>> Read more…

Universal vaccine could eliminate need for seasonal flu shots

A syringe is used to draw H1N1 swine flu vaccine. (Photo: AP Photo/Alex Brandon)

Canadian research has revealed a possible new way to develop an influenza vaccine that could eliminate the need for seasonal flu vaccinations.

Each year pharmaceutical companies manufacture and distribute a new flu vaccine to protect people against three different strains of influenza viruses that are expected to be most common during the upcoming flu season.

Rather than having to update a flu vaccine for each year, scientists have been at work to develop what they call a universal vaccine which protects against all types and strains of influenza.

Studying the 2009 H1N1 “swine flu” vaccine, a University of British Columbia research team found that that specific flu vaccine triggered the immune system to produce a number of antibodies that protect against many other flu viruses, including the dreaded H5NI avian (bird flu) strain of influenza.

Team leader Dr. John Schrader found that a protein in the flu virus called hemagglutinin (HA) is a lot like a flower with a head and a stem.  It’s the head of this protein that binds the flu virus to the healthy human cell, like an electrical plug into a socket.

Most vaccines, according to Schrader, help the body develop antibodies that attack the head of the protein in order to prevent infection. But, since the flu virus tends to mutate quickly, that part of the HA protein changes rapidly so new and different vaccines are needed for each flu season.

But Schrader and his research team found that the 2009 H1N1 vaccine also built up antibodies that attacked the stem of the protein, thereby neutralizing the flu virus.

“The stem plays such an integral role in penetrating the cell that it cannot change between different variants of the flu virus,” said Schrader.

According to Schrader, he has evidence producing vaccines based on a mix of flu viruses circulating in animals, but not humans, should have the same effect, possibly making influenza pandemics and seasonal influenza a relic of the past.

>>> Read more…

New research pinpoints origin of the domestic horse

A horse is reflected in a pool of water (Photo: AP Photo/David Duprey)

The domesticated horse originated in the steppes of modern-day Ukraine, southwest Russia and west Kazakhstan, mixing with local wild stocks as they spread throughout Europe and Asia, according to a new study.

Scientists from the University of Cambridge (UK) used a genetic database of more than 300 horses from across the Eurasian Steppe to reach their conclusion.

The new study finds the Equus ferus, the extinct wild ancestor of today’s domestic horse, migrated out of East Asia about 160,000 years ago, to be domesticated in the western Eurasian Steppe, their herds constantly replenished with wild horses as they spread across Eurasia.

“The spread of horse domestication differed from that of many other domestic animal species, in that spreading herds were augmented with local wild horses on an unprecedented scale,” said Dr. Vera Warmuth of the University of Cambridge’s Department of Zoology.

>>> Read more…

A smart door knob does more than just open or close doors. (Photo: Disney Research, Pittsburgh/Carnegie Mellon University)

Imagine having a doorknob that knows whether it should lock or unlock itself, based on how a user grips it; or a smartphone that silences itself if its user puts a finger to his or her lips; or  a chair which automatically adjusts the lighting in a room by sensing whether the user is leaning forward or reclining in the chair.

These and other applications could soon be possible with a new sensing technique developed by a collaborative research team of Disney Research, Pittsburgh and Carnegie Mellon University.

The Touché system uses something its developers call Swept Frequency Capacitive Sensing (SFCS), a more advanced form of capacitive touch-sensing technology, which is currently used in the touchscreens of most smartphones.

But, unlike today’s touchscreens which only sense electrical signals at one frequency, Touché’s SFCS technology can monitor signals across a broad range of signals, which would make it possible for the object to not only sense the touch itself, but also to recognize a wide range of complex motions and configurations of the person touching it.

Since different body tissues can produce a wide range of capacitive properties, the SFCS device can take advantage of these differences and produce multiple results, according to its developers.  And while today’s touchscreen technology senses signals from a person’s fingertips, the new Touché system can do so from different  parts of the finger or hand as well as other parts of the human body.

“Signal frequency sweeps have been used for decades in wireless communication, but as far as we know, nobody previously has attempted to apply this technique to touch interaction,” said Ivan Poupyrev, senior research scientist at Disney Research, Pittsburgh at Carnegie Mellon University. “Yet, in our laboratory experiments, we were able to enhance a broad variety of objects with high-fidelity touch sensitivity. When combined with gesture recognition techniques, Touché demonstrated recognition rates approaching 100 percent. That suggests it could immediately be used to create new and exciting ways for people to interact with objects and the world at large.”

To demonstrate Touché’s technology, the researchers came up with what they called a smart doorknob. Their smart door knob, depending on whether it was grasped, touched with one or two fingers or if were perhaps pinched, provides appropriate signals that program a door to lock or unlock itself, permit an authorized guest to enter while preventing an unauthorized guest, or possible intruder, from entering the premises.  The developers said they could also program the door knob to leave a vocal message when touched, such as “We’re away right now,” or “We’ll be back soon.”

The Disney/CMU researchers presented their findings today at CHI 2012, the Conference on Human Factors in Computing Systems in Austin, Texas, where they have been recognized with the group’s Best Paper Award.

(Images: Jossifresco via Wikimedia Commons/Creative Commons)

People who consider themselves highly religious are less motivated by compassion than non-believers, according to a new study from the University of California at Berkeley

After conducting three experiments, social scientists found that people who considered themselves to be “less religious” were consistently driven by compassion to be more generous to those in need.

As far as those described as being “highly religious”, researchers found that their measure of generosity was largely unrelated to how generous they were.

Compassion is defined by the study “as an emotion felt when people see the suffering of others which then motivates them to help, often at a personal risk or cost.”

“Overall, we find that for less religious people, the strength of their emotional connection to another person is critical to whether they will help that person or not,” said UC Berkeley social psychologist Robb Willer, a co-author of the study. “The more religious, on the other hand, may ground their generosity less in emotion, and more in other factors such as doctrine, a communal identity, or reputational concerns.”

Although the Berkeley study, published in Social Psychological and Personality Science, examined the connection between religion, compassion and generosity, it did not directly study the reasons for why highly religious people are less compelled by compassion to help others.

Researchers involved with the study do theorize however, that a sense of moral obligation, rather than compassion, drive religious people more strongly than those who are more non-religious.

Size matters to female crickets

(Image: Open Clip Art Library)

It turns out the size of a male cricket matters to female crickets, and the male crickets aren’t above faking it to attract a mate, according to a new study from England’s University of Bristol.

To attract females, male crickets sing loud and repetitive songs at night by rubbing their wings together. This sets the wings into a resonant vibration, which produces a loud and intense sound, allowing the female crickets to find them.  The lady crickets also listen for this sound in order to find the hottest guys.

The male cricket mating song contains many cues females can use to assess their desirability. However, most have thought the one attribute that couldn’t be faked or augmented was the sound which indicates the cricket’s size.

Males communicate their size through their mating song.  Lower pitched sounds are usually produced by larger males, while the sounds the smaller guys produce have a higher pitch. So, the females – who prefer larger male crickets – simply listen for those lower-pitched sounds to find the guy cricket of their dreams.

Experts have always thought the smaller males were stuck with making the high pitched, squeaky sounds.  But the study found that tiny and nearly transparent tree crickets, said to be highly unusual creatures, use temperature to change the pitch of their song making them sound much bigger than they really are.

Warmer temperatures made the tree crickets livelier and they called faster, producing sounds in a higher frequency mode. However, when it was cooler, the crickets behaved in the opposite manner, producing lower-pitched sounds making them sound much bigger than they really were, allowing the little guys to attract females.

Speaking more than one language fine-tunes hearing and enhances attention

(Image: Flickr/Creative Commons)

Speaking more than one language can enhance attention and working memory, according to a new study from Northwestern University, by fine tuning a person’s auditory nervous system, allowing them to manipulate verbal input.

The study’s research, led by Northwestern University’s bilingualism expert Viorica Marian and auditory neuroscientist Nina Kraus, found that speaking more than one language changes how the nervous system responds to sound.

“People do crossword puzzles and other activities to keep their minds sharp,” Marian said. “But the advantages we’ve discovered in dual language speakers come automatically simply from knowing and using two languages. It seems that the benefits of bilingualism are particularly powerful and broad, and include attention, inhibition and encoding of sound.”

The researchers, working with 23 bilingual (English and Spanish speaking) teenagers along with 25 teens who only spoke English, recorded their subjects brain-stem responses to complex speech sounds under loud and quiet conditions.

Both groups had the same response when the listening conditions were quiet.  But, when it wasn’t so quiet, and there was a bit of background noise, the researchers found that the brains of the bilingual teens were much better a picking up and detecting speech sounds.

“Bilinguals are natural jugglers,” said Marian. “The bilingual juggles linguistic input and, it appears, automatically pays greater attention to relevant versus irrelevant sounds. Rather than promoting linguistic confusion, bilingualism promotes improved ‘inhibitory control,’ or the ability to pick out relevant speech sounds and ignore others.”