This Week In Science

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Don't know where else to stick this, or even if its particularly noteworthy within the field, but a buddy just casually mentioned his liquid natural gas firm keeps methane cryogenically cooled to - 260 F. Absolute zero is -273.15 F. WTF

http://en.m.wikipedia.org/wiki/Absolute_zero

Ozone Layer Showing Signs Of Recovery

It’s been a dismal few decades for our troubled ozone layer, but it’s finally on the road to recovery, according to a comprehensive new assessment released on Wednesday. What’s more, it’s thanks to a laudable global effort to phase out the use of ozone-depleting substances, showing us what political determination can achieve.

Almost 300 scientists from 36 countries contributed to the detailed report, which was published by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO).

The ozone layer is a protective blanket of gas that shields us from harmful UV radiation emitted by the Sun. It started to decline during the 1980s and in 1985 scientists spotted a seasonal hole over Antarctica, prompting governments to start taking action to prevent further decline. It’s known that gases such as CFCs (chlorofluorocarbons) and halons—which were commonly used in products such as refrigerators and aerosols—can accelerate the depletion of ozone in the Earth’s stratosphere, so scientists and politicians across the globe put their heads together in a bid to reduce their use. In 1987, almost 200 countries signed the Montreal Protocol which was designed to phase out the use of ozone-depleting substances.

The ozone layer continued to decline throughout the early 1990s but has remained relatively unchanged since 2000. Now, thanks to the significant decrease in the atmospheric abundance of ozone-depleting gases, it is finally starting to show signs of future recovery. Without the Montreal Protocol, it is estimated that atmospheric levels of these gases could have increased tenfold by 2050. Furthermore, according to the UNEP, the protocol will have prevented some two million cases of skin cancer annually by 2030, alongside protecting wildlife and agriculture.



NASA

If signatories continue to fully comply with the Montreal Protocol, it is anticipated that the ozone layer above the mid-latitudes and Arctic will recover to 1980 levels before 2050. The seasonal hole above the Antarctic will take significantly longer to heal, however, since ozone-depleting substances can linger for many years in the atmosphere.

“International action on the ozone layer is a major environmental success story,” WMO Secretary-General Michel Jarraud said in a news release. “This should encourage us to display the same level of urgency and unity to tackle the even greater challenge of climate change.”

Since many ozone-depleting chemicals are also potent greenhouse gases, the protocol has also had the added bonus of benefiting climate through significantly reducing these emissions. However, the substances used to replace them (hydrofluorocarbons) are also greenhouses gases and their emissions are steadily growing. If this doesn’t change, they are anticipated to contribute significantly to global warming in the future.

Scientists will present their findings in November at the annual meeting of the Parties to the Montreal Protocol in Paris. The full report will be published next year.

[Via UNEP, BBC News and Live Science]

Physicists Achieve Quantum Teleportation of Photon Over 25 Kilometers

For the first time, a team of physicists have successfully teleported a quantum state of a photon to a crystal over 25 kilometers away through a fiber optic cable. This effectively showed that the photon’s quantum state, not its composition, is important to the teleportation process. The team was led by Nicolas Gisin of the University of Geneva and the results were published in the journal Nature Photonics. With this new paper, Gisin’s team has successfully squashed the previous record they set a decade ago by teleporting a quantum state of a proton 6 kilometers.

The quantum state of the photon is able to preserve information under extreme conditions, including the difference between traveling as light or becoming stored in the crystal like matter. The photon’s state acts as information that can be teleported along great distances using the optical fiber, and can be stored within the crystal. This was achieved due to a phenomenon in quantum mechanics known as entanglement, where two particles have a correlation, despite the fact that they aren’t touching and transmitting information to one another.

To test this and ensure what they were observing was actually happening, one photon was stored in a crystal while the other was sent along optical fiber, over a distance of 25 kilometers. The photon that was sent along the optical fiber collides with a third photon, which was assumed to destroy them both. However, the information from the first photon was transferred to the third photon in the collision, like the transfer of energy when one billiard ball hits another. The information from the third photon came back to the crystal where it could be measured to ensure the information was preserved between the first and the second.

The photon did not physically “teleport” as we are used to hearing about in science fiction, where someone’s body can moved from place to place in a matter of seconds. Instead, the information contained on the now-distant photon can be inferred based on what is seen with the information in the photon in the crystal. By knowing one, you already know the other. However, what the information actually is can't be known until it is examined.

Félix Bussières of Gisin’s team explained in a press release that it appears "that the quantum state of the two elements of light, these two entangled photons which are like two Siamese twins, is a channel that empowers the teleportation from light into matter.” Regardless if the information was in crystal or light, there wasn’t a change to the information itself. This could very well mean that the quantum state, not physical state, rules in quantum physics.

Quantum entanglement is the basis for theoretical quantum computing and quantum communication, though it will be a very long time before these results will have real-world implications. The achievements of Gisin's lab could also improve how quantum entanglement interactions are measured.

http://www.iflscience.com/physics/physicists-achieve-quantum-teleportation-photon-over-25-kilometers

Spinal Cord Stimulation Allows Completely Paralyzed Rats To Walk Again

Using electrical stimulation, scientists at the Swiss Federal Institute for Technology (EPFL) have helped paralyzed rats with severed spinal cords walk again. And it might not be too long before this promising treatment starts to help people as human trials could begin as early as next summer. The study has been published in Science Translational Medicine.

Spinal cord injury is one of the leading causes of paralysis in the US, and the outlook for the vast majority of patients is depressingly bleak. The spinal cord is essential for movement because it acts as a middle man between the brain and the rest of the body; when it is injured, the flow of information to other body parts can be disrupted, resulting in the inability to move some or all limbs. Unfortunately, there is no effective treatment, so for many the paralysis is permanent.

But recently, there have been some encouraging developments in treatment as scientists figured out a way to mimic the brain signals required for movement by directly stimulating the spinal cord with electrical pulses. Remarkably, this experimental therapy allowed four paraplegic men to regain some voluntary movement in their hips, ankles and toes.

The problem with this technique, which is known as epidural electrical stimulation (EES), is that the amplitude and frequency of electrical pulses need to be constantly adjusted, which is difficult to achieve while an individual is attempting to walk. To overcome this limitation, EPFL researchers have developed algorithms that automatically adjust the pulses in real-time during locomotion, dramatically improving the control of movement.

For the study, the researchers used paralyzed rats whose spinal cords were completely severed. They surgically implanted electrodes into their spines and then placed them on a treadmill, supporting them with a robotic harness. After testing out different pulses and monitoring walking patterns, the researchers discovered that there was a relationship between how high the rat lifted its limbs and pulse frequency. Using this information, the researchers were able to develop an algorithm that constantly monitored the rats’ movement. This data was then fed back into the system which allowed automatic, rapid adjustments in the stimulation in real time, mimicking the way that neurons fire naturally.

The rats were able to walk 1,000 steps without failure and were even able to climb staircases. “We have complete control of the rat’s hind legs,” EPFL neuroscientist Grégoire Courtine said in a news release. “The rat has no voluntary control of its limbs, but the severed spinal cord can be reactivated and stimulated to perform natural walking.”

It is hoped that a human size version of the system could be used in robot-assisted rehabilitation, which may help patients with incomplete spinal cord injuries learn to walk again. The researchers will therefore test their scaled-up system, called Gait Platform, in human trials as early as next summer.

http://www.youtube.com/watch?v=fxNRfxeFnjk

http://www.iflscience.com/health-and-medicine/spinal-cord-stimulation-allows-completely-paralyzed-rats-walk-again

Top stories of 2014...

New Cancer Therapy "Dissolves" Woman's Tumor In 3 Weeks

April 27, 2015 | by Justine Alford



In medicine, there is often the concern that a patient will not respond to a particular treatment, but in a turn for the books, physicians are now worried that a new cancer treatment might be so effective at eliminating tumors that it does more harm than good.

After receiving a single treatment of a novel combination therapy, a woman’s tumor seemingly “dissolved” from her chest in just three weeks, leaving her with a gaping hole in its place. The patient received the same cocktail of skin cancer drugs as almost 150 individuals enrolled in a clinical trial designed to test whether one of the therapies worked better on its own or when combined with another. While most patients did significantly better on the combination therapy, researchers were left gobsmacked by this woman’s rapid and dramatic response and have consequently described her case in the New England Journal of Medicine, alongside the trial results.

The therapies the scientists were investigating were the FDA-approved melanoma drugs Yervoy (ipilimumab) and Opdivo (nivolumab), which are both antibodies. The former works by interfering with a molecule that can switch off a type of cancer-fighting immune cell called a T-cell, whereas the latter blocks a pathway that can lead to the death of T-cells. Although they act in different ways, both drugs ultimately stimulate the immune system to fight cancer cells.

For the trial, 142 patients with melanoma that had spread to other parts of the body, or metastasized, were randomly assigned either Yervoy plus a placebo or Yervoy in combination with Opdivo. They found that, overall, patients in the combination group fared significantly better than those receiving Yervoy and the placebo. Fifty-three percent of these patients experienced at least 80% tumor shrinkage, and melanoma became undetectable in 22% by the end of the study—a remarkable response for stage IV cancer. None of the patients in the Yervoy monotherapy group achieved this outcome.

Although the trial is now over, it has been extended so that some advanced melanoma patients can still access the combination treatment, which is how the woman described earlier managed to receive the treatment, Live Science reports. According to the case report, the 49-year-old had undergone both surgery and chemotherapy to treat melanoma over a period of four years. Although she had several tumors removed, the disease was persistent and five months ago she developed a large mass under her left breast, which was presumed to have spread from the primary melanoma on her back.

She was given a single dose of the new combination therapy, but when she returned for her second just three weeks later, she reported that her tumor had “disappeared.” Alongside the obvious hole in her chest, CT scans confirmed that the large tumor had been completely eradicated. While such a rapid and dramatic response may sound desirable, the researchers have expressed concerns since if this were to happen to a tumor elsewhere in the body, such as the bowel or heart, it could have grave consequences.

“It is ironic that we are now concerned about the possibility of overly vigorous antimelanoma responses,” the researchers write.

[Via NEJM and Live Science]

http://www.iflscience.com/health-and-medicine/new-cancer-therapy-dissolves-womans-tumor-3-weeks