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can be used to corroborate age estimates inferred by other means

In the past, analyses of globular clusters and the Hubble constant

yielded vastly different ages for the Universe, and were offset by billions of years

based on the microwave background and Hubble constant, but it must have formed soon after the big bang

Within the errors, the age of HD 140283 does not conflict with the age of the Universe, 13.77 ± 0.06 billion years

Metal-poor stars can be used to constrain the age of the Universe because metal-content is typically a proxy for age

Heavier metals are generally formed in supernova explosions, which pollute the surrounding interstellar medium.

Stars subsequently born from that medium are more enriched with metals than their predecessors

each successive generation becoming increasingly enriched

HD 140283 exhibits less than 1% the iron content of the Sun, which provides an indication of its sizable age.

had been used previously to constrain the age of the Universe, but uncertainties tied to its estimated distance (at that time) made the age determination somewhat imprecise

obtain a new and improved distance for HD 140283 using the Hubble Space Telescope (HST), namely via the trigonometric parallax approach

distance uncertainty for HD 140283 was significantly reduced by comparison to existing estimates, thus resulting in a more precise age estimate for the star

The reliability of the age determined is likewise contingent on accurately determining the sample’s metal content

analyses of globular clusters and the Hubble constant yielded vastly different ages for the Universe

discrepant ages stemmed partly from uncertainties in the cosmic distance scale

determination of the Hubble constant relied on establishing (accurate) distances to galaxies

One of the key objectives envisioned for HST was to reduce uncertainties associated with the Hubble constant to <10%, thus providing an improved estimate for the age of the Universe

the mean implying an age near ~14 billion years

Determining a reliable age for stars in globular clusters is likewise contingent on the availability of a reliable distance

the study reaffirms that there are old stars roaming the solar neighborhood which can be used to constrain the age of the Universe

could be of great benefit for people deprived of limb movements, such as those with Lou Gehrig's disease (also known as ALS), the researchers say. It might also help to improve eye movement control in people with certain conditions such as dyslexia or ADHD and/or for experts, such as athletes or surgeons, whose activities strongly rely on eye movements

In everyday life, smooth pursuit eye movement is used to track moving targets

fact our eyes never cease to move

normally impossible to control those movements smoothly in any direction.

got a hint that smooth eye movements just might be possible in a completely accidental way

technology relies on changes in contrast to trick the eyes into the perception of motion

now working on a better version of his eye writer, and tests with ALS patients should start next year

He was moving his own eyes in front of an unusual visual display in his lab and discovered that it produced some odd effects. For one thing, he could see his own eye movements. With a little practice, he gradually discovered that he could control those eye movements, too.

analysis suggests that Y. huali differed from tyrannosaurids in its growth strategy13

a team of researchers at Massachusetts General Hospital in Boston successfully implanted lab grown kidneys into rats

Lungs from two deceased juveniles were obtained

The first lung was stripped of all of its cells leaving just a scaffolding of elastin and collagen

Healthy cells were then taken from the second lung and applied to the scaffolding

, the lung-to-be was placed in a glass tank full of a nutrient-rich solution where it soaked for four weeks.

the team repeated the whole exercise with another set of lungs and found the same result.

During that time, new cell growth filled in the scaffolding resulting in a new lung.

The researchers don't know how well the newly grown lung might work if it were implanted into a person, if at al

are confident that they are on the right track in growing lungs in a lab that will eventually be used to replace damaged lungs in actual patients

doesn't expect lab-grown lungs to be transplanted into humans for at least a dozen years

The team next plans to repeat the process with pig lungs and then to implant the results into a live pig to see how well they actually work

The stimulator delivers a continuous electrical current to the participants' lower spinal cords, mimicking signals the brain normally transmits to initiate movement

an initial study, published in May 2011

evaluated the effects of epidural stimulation in the first participant

who recovered a number of motor functions as a result of the intervention

three years later, the key findings documented

detail the impact of epidural stimulation in a total four participants, including new tests

What is revolutionary

is that the second, third and fourth participants

were able to execute voluntary movements immediately following the implantation and activation of the stimulator.

The participants' results and recovery time were unexpected, which led researchers to speculate that some pathways may be intact post-injury and therefore able to facilitate voluntary movements.

Two of the four subjects were diagnosed as motor and sensory complete injured with no chance of recovery at al

Because of epidural stimulation, they can now voluntarily move their hips, ankles and toes

groundbreaking for the entire field and offers a new outlook that the spinal cord, even after a severe injury, has great potential for functional recovery.

In epidural stimulation, the electrical current is applied at varying frequencies and intensities to specific locations on the lumbosacral spinal cord

corresponding to the dense neural bundles that largely control the movement of the hips, knees, ankles and toes

With the participants, once the signal was triggered, the spinal cord reengaged its neural network to control and direct muscle movements.

When coupling the intervention with rehabilitative therapy, the impact of epidural stimulation intensified

Over the course of the study, the researchers noted that the participants were able to activate movements with less stimulation, demonstrating the ability of the spinal network to learn and improve nerve functions

uncovered a fundamentally new intervention strategy that can dramatically affect recovery of voluntary movement in individuals with complete paralysis, even years after injury

The belief that no recovery is possible and complete paralysis is permanent has been challenged

Beyond regaining voluntary movement, the research participants have displayed a myriad of improvements in their overall health

increases in muscle mass and regulation of their blood pressure, as well as reduced fatigue and dramatic improvements to their sense of well-being.

all four men were able to bear weight independently, as reported by the team

The study offers hope that clinical therapies can be developed to advance treatment for the nearly 6 million Americans living with paralysis, including nearly 1.3 million with spinal cord injuries.

The four paralyzed participants ranged in neurological level from C7–T5 and were at least two years post-injury at the time of the intervention

Two of them had been rated "A" on the American Spinal Injury Association's classification system, meaning they had absolutely no sensation or cognition below the site of their injury

surprising the scientists, who believed at least some of the sensory pathway must be intact for epidural stimulation to be successful.

With this study, the investigators show that their findings about a motor complete patient regaining movement, as published three years ago in The Lancet, were not an anomaly

At the present time,

there are no effective evidence-based treatments for chronic spinal cord injury

, the implications of this study for the entire field are quite profound, and we can now envision a day when epidural stimulation might be part of a cocktail of therapies used to treat paralysis

first learned that a patient had regained voluntary control as a result of the therapy, we were cautiously optimistic

The research was funded by the Reeve Foundation and the National Institutes of Health

the Leona M. and Harry B. Helmsley Charitable Trust, the Kessler Foundation, the University of Louisville, the Jewish Hospital and St. Mary's Foundation, the Frazier Rehab Institute and University Hospital.

Investing in epidural stimulation

Now that spinal stimulation has been successful in four out of four patients, there is evidence to suggest a large cohort of individuals,

previously with little realistic hope of any meaningful recovery from spinal cord injury, may benefit from this intervention

how we see motor complete spinal cord injury

don't have to necessarily rely on regrowth of nerves in order to regain function

observed this in four out of four people suggests that this is actually a common phenomenon in those diagnosed with complete paralysis

The scientists are optimistic that the therapy intervention will continue to result in improved motor functions

based on observations from the research, there is strong evidence that with continued advancements of the epidural stimulator, individuals with complete spinal cord injuries will be able to bear weight independently, maintain balance and work towards stepping