Day: 09/26/2013

First mind-controlled bionic leg a ‘groundbreaking’ advance.

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After losing his lower right leg in a motorcycle accident four-and-a-half years ago, 32-year-old Zac Vawter has been fitted with an artificial limb that uses neurosignals from his upper leg muscles to control the prosthetic knee and ankle. The motorized limb is the first thought-controlled bionic leg, scientists at the Rehabilitation Institute of Chicago reported Wednesday in The New England Journal of Medicine.

“This is a groundbreaking development,” says lead author Levi Hargrove, a biomedical engineer and research scientist at RIC. “It allows people to seamlessly transition between walking along level ground and going up and down stairs and slopes.”

Until now, only thought-controlled bionic arms have been available to amputees.

In this Oct. 25, 2012 photo, Zac Vawter, fitted with an experimental "bionic" leg, is silhouetted on the Ledge at the Willis Tower in Chicago. Vawter ...

Brian Kersey / AP
On Oct. 25, 2012 Zac Vawter, fitted with an experimental “bionic” leg, climbed the 103 flights to the top of Willis Tower in Chicago.

When Vawter thinks he wants to move his leg, the brain signal travels down his spinal cord and through peripheral nerves and is picked up by electrodes in the bionic leg. Unlike robotic models currently on the market, the prosthesis allows a normal, smooth gait no matter the incline. Although the cost hasn’t been determined, a version could be available to the more than one million Americans with leg amputations within three to five years, the Chicago scientists said.

“It makes a phenomenal difference,” says Vawter, a software engineer from Yelm, Wash., whose right leg was amputated through the knee in 2009 after he crashed his motorcycle. Aware of the institute’s work on bionic arms, Vawter and his surgeon contacted Hargrove and the team developing the pioneering prosthesis. For nearly three years ending in October, 2012, Vawter would travel to the institute periodically.

Vawter would remove his mechanical leg, slip into the bionic one, and run through a set of experiments the scientists devised, suggesting improvements and providing feedback on what was working and what was not.

 

Now, after multiple revisions to the leg’s software and two major revisions to the leg’s mechanics, Vawter says he can walk up and down stairs the way he did before the accident. With his mechanical leg, Vawter says, “My sound leg goes up every step first, and I’m just dragging the prosthetic leg along behind me.” But with the bionic leg, “I go leg over leg,” he says. “The bionic leg listens to the various signals from my nerves and responds in a much more natural way.”

Some current prosthetic legs are purely mechanical, like Vawter’s; others are robotic and have a motor, a computer, and mechanical sensors that detect how much weight is being put on the prosthesis and the position of the knee. These allow people to walk well but don’t allow people to seamlessly ascend or descend stairs with a normal gait or to reposition their leg while sitting without manually moving it. The thought-controlled bionic leg is much more sophisticated. In additional to mechanical sensors, it has two motors, complex software, and a set of electrodes – essentially antennae – in its socket that pick up the tiny electrical signals that muscles in the upper leg generate when they contract.

Two electrodes pick up signals from the hamstring muscle, where the nerves that had run through Vawter’s lower leg were redirected during the amputation. “So when Zac is thinking about moving his ankle, his hamstring contracts,” says Hargrove.

 

More electrodes pick up signals from other muscles in the residual limb. The complex pattern recognition software contained in the on-board computer interprets these electrical signals from the upper leg as well as mechanical signals from the bionic leg and “figures out what Zac is trying to do,” says Hargrove.

 

The U.S. Army’s Telemedicine and Advanced Technology Research Center funded the Chicago study with an $8 million grant to add neural information to the control systems of advanced robotic leg prostheses. Devising a thought-controlled bionic leg has been more challenging than a thought-controlled bionic arm, says Hargrove.

That’s because the motors must be powerful enough to provide the energy to allow someone to stand and push along — and they must be small. Also, the computer control system must be safe.

“If there is a mistake or error that could cause someone to fall, that could be potentially catastrophic, and we want to avoid that at all costs,” says Hargrove.

The leg is a prototype so Vawter cannot take it home. Error rates in the software are small but need to be made smaller, says Hargrove and the leg itself needs to be made quieter and lighter. In addition, prolonged use can produce chafing where the residual limb contacts the electrodes in the bionic leg’s socket.

The ultimate cost of the final product is unknown, says Hargrove, although upper extremity prostheses range from $20,000 to $120,000. “We are leveraging developments in related industries to make sure we use low-cost components whenever possible,” Hargrove told NBC News.

Careful engineering will make it affordable. His goal is to restore “full ability” to all patients, especially the elderly. “This could mean the difference between living in their home longer and having to go to a nursing home,” says Hargrove.

Missouri Offers Free Vaccinations for Whooping Cough.

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What do you do when you are offered something free? If you’re like most people, you accept it, oftentimes when it’s something you will never use or don’t even like. So, when a state offers free vaccines, those with limited knowledge of their negative effects may begin lining up. Unfortunately, flu season is approaching, so millions will line up for this questionable anti-flu solution.

That’s the concern of Michelle Goldstein at VacTruth.com. Goldstein reports on a recent incidence in Missouri, where state officials launched a propaganda campaign aimed at vaccinating as many in the state as possible, by offering free Tdap vaccines in the St. Louis area.

The “giveaway” was recently announced in St. Louis, where the paper announced that incidence of whooping cough have risen to levels not seen since 1955, due in part because vaccinations given more than 10 years ago were wearing off. Last year, more than 41,000 cases of pertussis were reported nationwide; this is in contrast to 18,719 cases the year before.

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While St. Louis Today and the Missouri Department of Health are quick to point out all of the scary effects of whooping cough, they neglect to discuss the scary effects of the Tdap vaccine and the fact that pertussis can be effectively treated without conventional pharmaceutical means.

According to Goldstein:

“Health consequences resulting from the Tdap vaccine include encephalitis, brain damage and death. A comprehensive report made by the National Vaccine Information Center (NVIC) documents clearly the widespread health dangers associated with the Tdap vaccine. Tdap and DTap vaccines are currently used in the United States, replacing the DTP vaccine in 1996, but all three vaccines contain the dangerous pertussis toxin with unsafe additives.”

Exposing the Vaccination-Immunity Fraud

Also interesting, most of those who have recently contracted pertussis were actually vaccinated at some point. In other words, while there is solid proof of the vaccinations causing harm, there is no solid evidence that it can definitively prevent the disease.

In addition, whopping cough can be treated without prescription drugs. As a matter of fact, a successful bout of pertussis means lifelong immunity. In other words, once you have it you won’t get it again. What’s the most effective treatment for whooping cough? A vitamin C protocol that can dramatically reduce symptoms and complications.

Finally, the other conditions this Tdap vaccine “protects” against—tetanus and diphtheria—are not only uncommon in the U.S., but can similarly be prevented and treated with risk of complications being relatively low.

Since whooping cough can be problematic for young children, it’s important to do whatever you think is best as a parent; it’s just important to know truths behind the chosen solution.

The Most Horrifying Drug in the World Comes to the U.S.

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Krokodil, a heroin-like drug that rots the skin, has been reported in Arizona

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A flesh-eating drug called Krokodil, because it makes user’s skin scaly and green before it rots away, has arrived on American soil. The Banner Poison Control center in Arizona has reported the first two users of the drug — which has been available in Russia for more than a decade — here in the U.S.

Krokodil most closely resembles morphine or heroin and is injected into the veins. It is made of codeine, a painkiller often used in cough syrup, and a mix of other materials including gasoline, paint thinner, and alcohol. It has become popular in Russia, where it was first reported in 2002, because it is cheap–it can cost 20 times less than heroin according to Gawker–and can be made easily at home.

“As far as I know, these are the first cases in the United States that are reported,” Dr. Frank LoVechhio, co-medical director at Banner Good Samaritan Poison and Drug Information Center in Arizona, told CBS 5. “So we’re extremely frightened.” The average life span of a Krokodil user is two to three years, according to a 2011 TIME investigation of the drug’s prevalence in Russia.

When it is injected, the drug rots the skin by rupturing blood vessels, causing the tissue to die. As a result, the skin hardens and rots, sometimes even falling off to expose the bone.  ”These people are the ultimate in self-destructive drug addiction,” Dr. Ellen Marmur, chief of dermatological and cosmetic surgery at Mount Sinai Medical Center in New York City told Fox News, “Once you are an addict at this level, any rational thinking doesn’t apply.”

Rosacea may be caused by mite faeces in your pores.

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There are tiny bugs closely related to spiders living in the pores of your face. They have long been considered mere passengers, doing no harm beyond upsetting the squeamish. But they may be causing an ancient skin disease that is estimated to affect between 5 and 20 per cent of people worldwide, and 16 million in the US alone.

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People aged between 30 and 60, especially women, sometimes developrosacea: red inflamed skin, with swelling, roughness and fine, visible blood vessels, usually in the central zone of the face. Severe cases can resemble acne, irritate the eyes and lead to the bulbous red nose seen in caricatures of the elderly.

The disease affects all races but is known as the “curse of the Celts” as it is thought to especially affect people with very fair skin, although it may simply be more visible on their skin. Rosacea is commonly blamed on another alleged Celtic curse – excessive drinking. But while alcohol can trigger a flare-up, so can many other kinds of stress. Teetotallers are just as susceptible, according to the US National Rosacea Society.

Kevin Kavanagh of the National University of Ireland, in Maynooth, now thinks he has discovered the cause – and it isn’t for the faint-hearted.

Tiny mites – eight-legged arachnids related to spiders – live in the pores of our facial skin. They are particularly fond of the hair follicles of eyebrows and eyelashes, and the oily pores most common on the nose, forehead and cheeks. Called Demodex, the mites eat sebum, or facial oil, and colonise your face at puberty.

 

They crawl about your face in the dark to mate, then crawl back into pores to lay their eggs and die. Healthy adults have around one or two mites per square centimetre of facial skin. People with rosacea, however, can have 10 times as many, says Kavanagh. Research suggests that the stress that causes flare-ups of rosacea changes the chemicals in sebum, making it better food for mites.

Rosacea often improves with antibacterial drugs that don’t affect the mites, such as tetracyclines. Kavanagh thinks this is because rosacea is caused by a reaction to bacteria in the mite’s faeces.

Demodex does not have an anus and therefore cannot get rid of its faeces. “Their abdomen just gets bigger and bigger, and when they die and decompose they release their faeces all at once in the pore,” says Kavanagh. When the mites are numerous, he believes that the material is enough to trigger an immune reaction, inflammation and tissue damage.

Kavanagh notes that one kind of bacteria in the mites’ guts, Bacillus oleronius, is killed by the antibiotics that work against rosacea, and not by other types of antibiotics. His lab reported in June that 80 per cent of people with the most common kind of rosacea have immune cells in their blood that react strongly to two proteins from B. Oleronius, releasing triggers of inflammation. Only 40 per cent of people without rosacea have this reaction.

Kavanagh is now trying to get funding to develop antibodies to the bacterial proteins, to track their location and link them more firmly to the disease. Ultimately, treatments aimed at the trigger proteins may prevent rosacea.

Source: Journal of Medical Microbiology

 

 

Seeing light in a new light.

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Scientists create never-before-seen form of matter

Harvard and MIT scientists are challenging the conventional wisdom about light, and they didn’t need to go to a galaxy far, far away to do it.

Working with colleagues at the Harvard-MIT Center for Ultracold Atoms, a group led by Harvard Professor of Physics Mikhail Lukin and MIT Professor of Physics Vladan Vuletic have managed to coax photons into binding together to form molecules – a state of matter that, until recently, had been purely theoretical. The work is described in a September 25 paper inNature.

The discovery, Lukin said, runs contrary to decades of accepted wisdom about the nature of light. Photons have long been described as massless particles which don’t interact with each other – shine two laser beams at each other, he said, and they simply pass through one another.

“Photonic molecules,” however, behave less like traditional lasers and more like something you might find in science fiction – the light saber.

“Most of the properties of light we know about originate from the fact that photons are massless, and that they do not interact with each other,” Lukin said. “What we have done is create a special type of medium in which photons interact with each other so strongly that they begin to act as though they have mass, and they bind together to form molecules. This type of photonic bound state has been discussed theoretically for quite a while, but until now it hadn’t been observed.

“It’s not an in-apt analogy to compare this to light sabers,” Lukin added. “When these photons interact with each other, they’re pushing against and deflect each other. The physics of what’s happening in these molecules is similar to what we see in the movies.”

To get the normally-massless photons to bind to each other, Lukin and colleagues, including Harvard post-doctoral fellow Ofer Fisterberg, former Harvard doctoral student Alexey Gorshkov and MIT graduate students Thibault Peyronel and Qiu Liang couldn’t rely on something like the Force – they instead turned to a set of more extreme conditions.

Researchers began by pumped rubidium atoms into a vacuum chamber, then used lasers to cool the cloud of atoms to just a few degrees above absolute zero. Using extremely weak laser pulses, they then fired single photons into the cloud of atoms.

As the photons enter the cloud of cold atoms, Lukin said, its energy excites atoms along its path, causing the photon to slow dramatically. As the photon moves through the cloud, that energy is handed off from atom to atom, and eventually exits the cloud with the photon.

“When the photon exits the medium, its identity is preserved,” Lukin said. “It’s the same effect we see with refraction of light in a water glass. The light enters the water, it hands off part of its energy to the medium, and inside it exists as light and matter coupled together, but when it exits, it’s still light. The process that takes place is the same it’s just a bit more extreme – the light is slowed considerably, and a lot more energy is given away than during refraction.”

When Lukin and colleagues fired two photons into the cloud, they were surprised to see them exit together, as a single molecule.

The reason they form the never-before-seen molecules?

An effect called a Rydberg blockade, Lukin said, which states that when an atom is excited, nearby atoms cannot be excited to the same degree. In practice, the effect means that as two photons enter the atomic cloud, the first excites an atom, but must move forward before the second photon can excite nearby atoms.

The result, he said, is that the two photons push and pull each other through the cloud as their energy is handed off from one atom to the next.

“It’s a photonic interaction that’s mediated by the atomic interaction,” Lukin said. “That makes these two photons behave like a molecule, and when they exit the medium they’re much more likely to do so together than as single photons.”

While the effect is unusual, it does have some practical applications as well.

“We do this for fun, and because we’re pushing the frontiers of science,” Lukin said. “But it feeds into the bigger picture of what we’re doing because photons remain the best possible means to carry quantum information. The handicap, though, has been that photons don’t interact with each other.”

To build a quantum computer, he explained, researchers need to build a system that can preserve quantum information, and process it using quantum logic operations. The challenge, however, is that quantum logic requires interactions between individual quanta so that quantum systems can be switched to perform information processing.

“What we demonstrate with this process allows us to do that,” Lukin said. “Before we make a useful, practical quantum switch or photonic logic gate we have to improve the performance, so it’s still at the proof-of-concept level, but this is an important step. The physical principles we’ve established here are important.”

The system could even be useful in classical computing, Lukin said, considering the power-dissipation challenges chip-makers now face. A number of companies – including IBM – have worked to develop systems that rely on optical routers that convert light signals into electrical signals, but those systems face their own hurdles.

Lukin also suggested that the system might one day even be used to create complex three-dimensional structures – such as crystals – wholly out of light.

“What it will be useful for we don’t know yet, but it’s a new state of matter, so we are hopeful that new applications may emerge as we continue to investigate these photonic molecules’ properties,” he said.

The TomTato: Plant which produces both potatoes and tomatoes launched in UK.

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Plant can grow sweet cherry tomatoes while producing white potatoes.

A plant which produces both potatoes and tomatoes, described as a “veg plot in a pot”, has been launched in the UK.

The TomTato can grow more than 500 sweet cherry tomatoes while producing white potatoes.

Horticultural mail order company Thompson & Morgan, which is selling the plants for £14.99 each, said the hybrid plants were individually hand-crafted and not a product of genetic engineering.

Grafted potato-tomato plants have already been produced in the UK, but Thompson & Morgan says this is the first time they have been successfully produced commercially.

The company says the tomatoes are far sweeter than those available in supermarkets.

Paul Hansord, horticultural director at the company, said he first had the idea for the plant 15 years ago in the US, when he visited a garden where someone had planted a potato under a tomato as a joke.

He said: “The TomTato has been trialled for several years and the end result is far superior than anything I could have hoped for, trusses full of tomatoes which have a flavour that makes shop tomatoes inedible, as well as, a good hearty crop of potatoes for late in the season.

“It has been very difficult to achieve the TomTato because the tomato stem and the potato stem have to be the same thickness for the graft to work, it is a very highly skilled operation.

“We have seen similar products, however on closer inspection the potato is planted in a pot with a tomato planted in the same pot – our plant is one plant and produces no potato foliage.”

The plants can be grown either outside or inside, as long as they are in a large pot or bag.

A similar product, dubbed the “Potato Tom”, was launched in garden centres in New Zealand this week.

Breast-feeding not linked to type 1 diabetes in high-risk population.

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An analysis of data from children enrolled in the MIDIA study indicates no association between breast-feeding and the risk for developing type 1 diabetes or autoislet autoimmunity.

Multivariate analysis of the data showed that the only variable linked to type 1 diabetes or autoislet immunity was having a first-degree relative with type 1 diabetes (P<.001). After adjustment for this factor, researchers found no significant association between development of type 1 diabetes and full breast-feeding (OR=1.28; P=.66) or any breast-feeding (OR=1.01; P=.99). Similar results were noted for full breast-feeding (OR=1.3; P=.41) or any breast-feeding (OR=1.25; P=.51) and islet autoimmunity.

For the study, the researchers assessed data from the MIDIA prospective cohort study, which included children with the high-risk human leukocyte antigen (HLA) genotype. Of 48,000 children genotyped, 1,047 had the high-risk HLA genotype. At 3, 6, 9 and 12 months of age, parents filled out questionnaires and the researchers obtained blood samples from the children. Full and any breast-feeding were defined using WHO criteria, and logistic regression analyses were used to identify the relationship between type 1 diabetes and islet autoimmunity and full or any breast-feeding and parent or infant characteristics.

Source: Endocrine Today.