3-D printed wrist splints for arthritis sufferers

Date:

July 1, 2014

Source:

University of Loughborough

Summary:

A computer software concept has been developed that will enable clinicians with no experience in Computer Aided Design (CAD) to design and make custom-made 3D printed wrist splints for rheumatoid arthritis sufferers. The 3D printed splints are not only more comfortable and attractive but potentially cheaper than the current ones that are 'ugly, bulky, and can make a patients arm sweat'.

A Loughborough University lecturer has developed a computer software concept that will enable clinicians with no experience in Computer Aided Design (CAD) to design and make custom-made 3D printed wrist splints for rheumatoid arthritis sufferers.

Dr Abby Paterson, from the Design School, said: "I wanted to give clinicians the ability to make splints they have not been able to make before. They can improve the aesthetics, the fit, and integrate extra bits of functionality they couldn't do before as a result of our Additive Manufacturing facilities here at Loughborough University. Thanks to our Objet Connex machine, we can integrate multiple materials in a single splint such as rubber-like integral hinges or cushioning features but, more importantly, the specialised software prototype we've developed will enable clinicians to design these splints for their patients."

The 3D printed splints are not only more comfortable and attractive but potentially cheaper than the current ones that are 'ugly, bulky, and can make a patients arm sweat'. As a result patients do not use them as often as they should.

The splints, which provide joint protection, rest, and promote pain relief,could be a major boost for sufferers of rheumatoid arthritis, the second most common type of arthritis in the UK which affects more than 400,000 people.

The splints are made by scanning a patient's arm in the 'appropriate position'. A 3D model splint is then designed based on the scan to generate a computer model.

The 3D printer can then produce as many splints as are needed at the touch of a button. They can be any colour, feature multiple materials, have a lattice design to aid ventilation and any type of fastening the patient requires.

The 3D CAD software prototype was shown to certified splinting practitioners, such as occupational therapists and physiotherapists.

Dr Paterson said: "The practitioners were very excited by new, novel ideas to expand the possibilities available to them, such as integrated rubber borders for increased comfort."

The 3D CAD software prototype is the product of Dr Paterson's PhD and development ‎work is still needed on the software and materials. ‎

Dr Paterson was supervised during her PhD by Dr Richard Bibb and Dr Ian Campbell. Dr Bibb came up with the idea for bespoke wrist splints in the late 1990's.

Dr Bibb and Dr Paterson are currently pursuing opportunities to perform a 'thorough cost analysis' of providing the service.

Dr Bibb says the 3D splints could be cheaper than the current ones because the design and manufacture stages have been separated. He believes they will be cost-effective for the NHS while the 'sky's the limit' in the private sector.

Dr Bibb, Reader in Medical Applications of Design in the Design School, said: "We are in the development phase. The research has proved that this is desirable and the clinicians want it. We know there's lots of potential."

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Story Source:

The above story is based on materials provided by University of Loughborough.Note: Materials may be edited for content and length.

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In human evolution, changes in skin's barrier set northern Europeans apart

Date:

June 30, 2014

Source:

University of California, San Francisco (UCSF)

Summary:

The popular idea that northern Europeans developed light skin to absorb more UV light so they could make more vitamin D -- vital for healthy bones and immune function -- is questioned by researchers in a new study. Ramping up the skin’s capacity to capture UV light to make vitamin D is indeed important, however, researchers concluded in their study that changes in the skin’s function as a barrier to the elements made a greater contribution than alterations in skin pigment in the ability of northern Europeans to make vitamin D.

The popular idea that Northern Europeans developed light skin to absorb more UV light so they could make more vitamin D – vital for healthy bones and immune function – is questioned by UC San Francisco researchers in a new study published online in the journal Evolutionary Biology

Ramping up the skin’s capacity to capture UV light to make vitamin D is indeed important, according to a team led by Peter Elias, MD, a UCSF professor of dermatology. However, Elias and colleagues concluded in their study that changes in the skin’s function as a barrier to the elements made a greater contribution than alterations in skin pigment in the ability of Northern Europeans to make vitamin D.

Elias’ team concluded that genetic mutations compromising the skin’s ability to serve as a barrier allowed fair-skinned Northern Europeans to populate latitudes where too little ultraviolet B (UVB) light for vitamin D production penetrates the atmosphere.

Among scientists studying human evolution, it has been almost universally assumed that the need to make more vitamin D at Northern latitudes drove genetic mutations that reduce production of the pigment melanin, the main determinant of skin tone, according to Elias.

“At the higher latitudes of Great Britain, Scandinavia and the Baltic States, as well as Northern Germany and France, very little UVB light reaches the Earth, and it’s the key wavelength required by the skin for vitamin D generation,” Elias said.

“While is seems logical that the loss of the pigment melanin would serve as a compensatory mechanism, allowing for more irradiation of the skin surface and therefore more vitamin D production, this hypothesis is flawed for many reasons,” he continued. “For example, recent studies show that dark-skinned humans make vitamin D after sun exposure as efficiently as lightly-pigmented humans, and osteoporosis – which can be a sign of vitamin D deficiency – is less common, rather than more common, in darkly-pigmented humans.”

Furthermore, evidence for a south to north gradient in the prevalence of melanin mutations is weaker than for this alternative explanation explored by Elias and colleagues.

In earlier research, Elias began studying the role of skin as a barrier to water loss. He recently has focused on a specific skin-barrier protein called filaggrin, which is broken down into a molecule called urocanic acid – the most potent absorber of UVB light in the skin, according to Elias. “It’s certainly more important than melanin in lightly-pigmented skin,” he said.

In their new study, the researchers identified a strikingly higher prevalence of inborn mutations in the filaggrin gene among Northern European populations. Up to 10 percent of normal individuals carried mutations in the filaggrin gene in these northern nations, in contrast to much lower mutation rates in southern European, Asian and African populations.

Moreover, higher filaggrin mutation rates, which result in a loss of urocanic acid, correlated with higher vitamin D levels in the blood. Latitude-dependent variations in melanin genes are not similarly associated with vitamin D levels, according to Elias. This evidence suggests that changes in the skin barrier played a role in Northern European’s evolutionary adaptation to Northern latitudes, the study concluded.

Yet, there was an evolutionary tradeoff for these barrier-weakening filaggrin mutations, Elias said. Mutation bearers have a tendency for very dry skin, and are vulnerable to atopic dermatitis, asthma and food allergies. But these diseases have appeared only recently, and did not become a problem until humans began to live in densely populated urban environments, Elias said.

The Elias lab has shown that pigmented skin provides a better skin barrier, which he says was critically important for protection against dehydration and infections among ancestral humans living in sub-Saharan Africa. But the need for pigment to provide this extra protection waned as modern human populations migrated northward over the past 60,000 years or so, Elias said, while the need to absorb UVB light became greater, particularly for those humans who migrated to the far North behind retreating glaciers less than 10,000 years ago.

The data from the new study do not explain why Northern Europeans lost melanin. If the need to make more vitamin D did not drive pigment loss, what did? Elias speculates that, “Once human populations migrated northward, away from the tropical onslaught of UVB, pigment was gradually lost in service of metabolic conservation. The body will not waste precious energy and proteins to make proteins that it no longer needs.”

For the Evolutionary Biology study, labeled a “synthesis paper” by the journal, Elias and co-author Jacob P. Thyssen, MD, a professor at the University of Copenhagen, mapped the mutation data and measured the correlations with blood levels of vitamin D. Labs throughout the world identified the mutations. Daniel Bikle, MD, PhD, a UCSF professor of medicine, provided expertise on vitamin D metabolism.

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Story Source:

The above story is based on materials provided by University of California, San Francisco (UCSF). The original article was written by Jeffrey Norris. Note: Materials may be edited for content and length.

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Journal Reference:

1. Jacob P. Thyssen, Daniel D. Bikle, Peter M. Elias. Evidence That Loss-of-Function Filaggrin Gene Mutations Evolved in Northern Europeans to Favor Intracutaneous Vitamin D3 Production. Evolutionary Biology, 2014; DOI:10.1007/s11692-014-9282-7

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Potentially habitable Earth-like planet discovered; May have similar temperatures to our planet

Date:

June 30, 2014

Source:

University of New South Wales

Summary:

A potentially habitable Earth-like planet that is only 16 light years away has been discovered. The "super-Earth" planet, GJ 832 c, takes 16 days to orbit its red-dwarf star, GJ 832, and has a mass at least five times that of Earth. It receives about the same average stellar energy as Earth does and may have similar temperatures to our planet. These characteristics put it among the top three most Earth-like planets.

AUNSW-led team of researchers has discovered a potentially habitable Earth-like planet that is only 16 light years away.

The "super-Earth" planet, GJ 832 c, takes 16 days to orbit its red-dwarf star, GJ 832, and has a mass at least five times that of Earth.

It receives about the same average stellar energy as Earth does, because red dwarfs shine more dimly than our Sun, and may have similar temperatures to our planet.

These characteristics put it among the top three most Earth-like planets, according to the Earth Similarity Index developed by scientists at the University of Puerto Rica in Arecibo.

The international team, led by Dr Robert Wittenmyer in the UNSW School of Physics, report their finding of the planet online ahead of publication in theAstrophysical Journal.

Team member and Head of UNSW's Exoplanetary Science research group, Professor Chris Tinney, says that if the planet has a similar atmosphere to Earth it may be possible for life to survive, although seasonal shifts would be extreme.

"However, given the large mass of the planet, it seems likely that it would possess a massive atmosphere, which may well render the planet inhospitable. A denser atmosphere would trap heat and could make it more like a super-Venus and too hot for life," says Professor Tinney.

The planet was discovered from its gravitational pull on its parent star, which causes the star to wobble slightly. Members of the Anglo-Australian Planet Search team used the Anglo-Australian Telescope to make observations of the planet.

Their data were combined with observations from the 6.5m Magellan Telescope and the European Southern Observatory 3.6m telescope (both in Chile) to make this new discovery.

This team had previously found, in 2009, that the star has a cold Jupiter-like planet with a near-circular orbit of about nine years, called Gliese GJ b.

"With an outer giant planet and an interior potentially rocky planet, this planetary system can be thought of as a miniature version of our Solar System," says Professor Tinney.

On the Earth Similarity Index, or ESI, the highest ranking exoplanet is Gliese 667C c, which is about 23 light years away. It has an ESI of 0.84 compared to Earth's maximum score of 1.0

Next on the list is Kepler-62 e with an ESI of 0.83, although it is much further away -- about 1,200 light years distant. And the new planet -- the closest at just 16 light years away -- comes in third with an ESI of 0.81.

For comparison, the Milky Way is about 100,000 light years across.

The team includes researchers from Australia, the UK, Finland, the US, Italy and Chile.

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Story Source:

The above story is based on materials provided by University of New South Wales.Note: Materials may be edited for content and length.

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Monkeys also believe in winning streaks

Date:

June 29, 2014

Source:

University of Rochester

Summary:

Humans have a well-documented tendency to see winning and losing streaks in situations that, in fact, are random. But scientists disagree about whether the “hot-hand bias” is a cultural artifact picked up in childhood or a predisposition deeply ingrained in the structure of our cognitive architecture.

Humans have a well-documented tendency to see winning and losing streaks in situations that, in fact, are random. But scientists disagree about whether the "hot-hand bias" is a cultural artifact picked up in childhood or a predisposition deeply ingrained in the structure of our cognitive architecture.

Now in the first study in non-human primates of this systematic error in decision making, researchers find that monkeys also share our unfounded belief in winning and losing streaks. The results suggests that the penchant to see patterns that actually don't exist may be inherited -- an evolutionary adaptation that may have provided our ancestors a selective advantage when foraging for food in the wild, according to lead author Tommy Blanchard, a doctoral candidate in brain and cognitive sciences at the University of Rochester.

The cognitive bias may be difficult to override even in situations that are truly random. This inborn tendency to feel that we are on a roll or in a slump may help explain why gambling can be so alluring and why the stock market is so prone to wild swings, said coauthor Benjamin Hayden, assistant professor brain and cognitive sciences at the University of Rochester.

Hayden, Blanchard, and Andreas Wilke, an assistant professor of psychology at Clarkson University, reported their findings in the July issue of the Journal of Experimental Psychology: Animal Learning and Cognition.

To measure whether monkeys actually believe in winning streaks, the researchers had to create a computerized game that was so captivating monkeys would want to play for hours. "Luckily, monkeys love to gamble," said Blanchard. So the team devised a fast-paced task in which each monkey could choose right or left and receive a reward when they guessed correctly.

The researchers created three types of play, two with clear patterns (the correct answer tended to repeat on one side or to alternate from side to side) and a third in which the lucky pick was completely random. Where clear patterns existed, the three rhesus monkeys in the study quickly guessed the correct sequence. But in the random scenarios, the monkeys continued to make choices as if they expected a "streak." In other words, even when rewards were random, the monkeys favored one side.

The monkeys showed the hot-hand bias consistently over weeks of play and an average of 1,244 trials per condition. "They had lots and lots of opportunities to get over this bias, to learn and change, and yet they continued to show the same tendency," said Blanchard.

So why do monkeys and humans share this false belief in a run of luck even when faced over and over with evidence that the results are random? The authors speculate that the distribution of food in the wild, which is not random, may be the culprit. "If you find a nice juicy beetle on the underside of a log, this is pretty good evidence that there might be a beetle in a similar location nearby, because beetles, like most food sources, tend to live near each other," explained Hayden.

Evolution has also primed our brains to look for patterns, added Hayden. "We have this incredible drive to see patterns in the world, and we also have this incredible drive to learn. I think it's very related to why we like music, and why we like to do crossword puzzles, Sudoku, and things like that. If there's a pattern there, we're on top of it. And if there may or may not be a pattern there, that's even more interesting."

Understanding the hot-hand bias could inform treatment for gambling addiction and provide insights for investors, said Hayden. "If a belief in winning streaks is hardwired, then we may want to look for more rigorous retaining for individuals who cannot control their gambling. And investors should keep in mind that humans have an inherited bias to believe that if a stock goes up one day, it will continue to go up."

The results also could provide nuance to our understanding of free will, said Blanchard, who was drawn to the study of decision making during prior graduate training in philosophy. "Biases in our decision-making mechanisms, like this bias towards belief in winning and losing streaks, say something really deep about what sorts of creatures we are. We often like to think we make decisions based only on the information we're conscious of. But we're not always aware of why we make certain decisions or believe certain things.

"We're a complex mix of biases and heuristics and statistical reasoning. When you put it all together, that's how you get sophisticated behavior. We don't know where a lot of these biases come from, but this study -- and others like it -- suggest many of them are due to cognitive mechanisms we share with our primate relatives," said Blanchard.

This research was supported by grants from the National Science Foundation and the Brain and Behavior Research Foundation to Hayden.

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Story Source:

The above story is based on materials provided by University of Rochester. Note: Materials may be edited for content and length.

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Journal Reference:

1. Tommy C. Blanchard, Andreas Wilke, Benjamin Y. Hayden. Hot-hand bias in rhesus monkeys.. Journal of Experimental Psychology: Animal Learning and Cognition, 2014; 40 (3): 280 DOI: 10.1037/xan0000033

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