from the world's big
NASA’s zero-gravity plane: How astronauts train for microgravity
A lot goes into being weightless.
Dr. Michelle Thaller is an astronomer who studies binary stars and the life cycles of stars. She is Assistant Director of Science Communication at NASA. She went to college at Harvard University, completed a post-doctoral research fellowship at the California Institute of Technology (Caltech) in Pasadena, Calif. then started working for the Jet Propulsion Laboratory's (JPL) Spitzer Space Telescope. After a hugely successful mission, she moved on to NASA's Goddard Space Flight Center (GSFC), in the Washington D.C. area. In her off-hours often puts on about 30lbs of Elizabethan garb and performs intricate Renaissance dances. For more information, visit NASA.
MICHELLE THALLER: Jack, you had the question, how do we remove gravity from the anti-gravity chambers that astronauts train in? And you've probably seen films of astronauts in training, floating around in a closed chamber. And it does kind of look like we may have something that can actually shield against gravity. Well, for one thing, I really wish we did because just think about how useful that would be. Think about having, say, a construction site, and you can remove all of the gravity. You could actually move things around really easily. There's so many applications for having some sort of anti-gravity device, but we don't have one.
There is no way to shield astronauts here on the earth from the We train astronauts by putting them up in an airplane and then having the airplane fly very, very carefully on an arc to throw everybody up at just the right rate so they're floating. It may have actually happened to you. You may have been on an airplane, and the airplane actually sort of arced around, and you felt yourself thrown up a little bit. So that's actually what we do in a very controlled way. We only can get about a minute's worth of weightlessness that way. The airplane flies in arc and then goes around again and flies another one. So the astronauts train by doing this over, and over, One of the really amazing applications of this was in the movie Apollo 13.
If you look very carefully, it's a very realistic depiction of astronauts floating around in the weightlessness of space. And that's because they really were weightless. They actually put movie sets inside this aircraft and filmed one minute at a time. The footage of the astronauts floating around the lunar module, for example. Now, this sort of training where one minute you're weightless, and then all of a sudden you're not, and then you're weightless again has a bit of an effect on people's stomach. And, in fact, the NASA nickname for this plane is the Vomit Comet.
It's something that can actually make you feel pretty sick to your stomach, but a lot of astronauts in training also find it really fun. And I've heard it mentioned that there are some pilots that are better than others at doing just the right arc. There are some pilots that as you fly, you're up against the ceiling, up against the floor, up against the ceiling. And then there are ones that get really, really smooth so you have the longest possible time in weightlessness. And, in fact, I heard that the pilot that was best at it would actually put a pencil in front of him as he began the arc to make it feel like you were weightless. And then he would fly the plane around the pencil, trying to keep that pencil in the same position as you went through the weightlessness arc.
So there's no way we can shield from gravity. We only can train astronauts a minute at a time in these aircraft. The other way we train them is by simulating a weightless environment the best we can by using water, by using really, really big swimming pools. At the Johnson Space Center-- one of my favorite places to go in all of NASA — there is a swimming pool, a pool so big that we actually have an entire scale model of a space station underneath the water. The same size as the space station. We put astronauts in basically scuba gear. They have their helmets. There's air being pumped through there. And they can float around and practice doing spacewalks outside the space station in the water. And then all around them, there are actually real scuba divers, ready to assist them to make sure everything's going well. And I've had friends who have actually served this way. They've actually been scuba divers that help astronauts train. So, unfortunately, there's no way to shield from gravity here on the Earth.
Gravity is of curvature of space and time. We have no way to manipulate that with our current technology, so we have to fake it. Astronauts have to either be in aircraft that are flying arcs or pretending to be weightless under the water,
- There is no way to shield astronauts on earth from the effects of gravity.
- Astronauts train for space by going on an airplane that flies high at an arc so that the force lifts them in the air. However, we can only achieve about a minute's worth of weightlessness this way.
- NASA researchers have nicknamed this plane the "Vomit Comet."
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Duke University researchers might have solved a half-century old problem.
- Duke University researchers created a hydrogel that appears to be as strong and flexible as human cartilage.
- The blend of three polymers provides enough flexibility and durability to mimic the knee.
- The next step is to test this hydrogel in sheep; human use can take at least three years.
Duke researchers have developed the first gel-based synthetic cartilage with the strength of the real thing. A quarter-sized disc of the material can withstand the weight of a 100-pound kettlebell without tearing or losing its shape.
Photo: Feichen Yang.<p>That's the word from a team in the Department of Chemistry and Department of Mechanical Engineering and Materials Science at Duke University. Their <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202003451" target="_blank">new paper</a>, published in the journal,<em> Advanced Functional Materials</em>, details this exciting evolution of this frustrating joint.<br></p><p>Researchers have sought materials strong and versatile enough to repair a knee since at least the seventies. This new hydrogel, comprised of three polymers, might be it. When two of the polymers are stretched, a third keeps the entire structure intact. When pulled 100,000 times, the cartilage held up as well as materials used in bone implants. The team also rubbed the hydrogel against natural cartilage a million times and found it to be as wear-resistant as the real thing. </p><p>The hydrogel has the appearance of Jell-O and is comprised of 60 percent water. Co-author, Feichen Yang, <a href="https://today.duke.edu/2020/06/lab-first-cartilage-mimicking-gel-strong-enough-knees" target="_blank">says</a> this network of polymers is particularly durable: "Only this combination of all three components is both flexible and stiff and therefore strong." </p><p> As with any new material, a lot of testing must be conducted. They don't foresee this hydrogel being implanted into human bodies for at least three years. The next step is to test it out in sheep. </p><p>Still, this is an exciting step forward in the rehabilitation of one of our trickiest joints. Given the potential reward, the wait is worth it. </p><p><span></span>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a>, <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank">Facebook</a> and <a href="https://derekberes.substack.com/" target="_blank">Substack</a>. His next book is</em> "<em>Hero's Dose: The Case For Psychedelics in Ritual and Therapy."</em></p>
An algorithm may allow doctors to assess PTSD candidates for early intervention after traumatic ER visits.
- 10-15% of people visiting emergency rooms eventually develop symptoms of long-lasting PTSD.
- Early treatment is available but there's been no way to tell who needs it.
- Using clinical data already being collected, machine learning can identify who's at risk.
The psychological scars a traumatic experience can leave behind may have a more profound effect on a person than the original traumatic experience. Long after an acute emergency is resolved, victims of post-traumatic stress disorder (PTSD) continue to suffer its consequences.
In the U.S. some 30 million patients are annually treated in emergency departments (EDs) for a range of traumatic injuries. Add to that urgent admissions to the ED with the onset of COVID-19 symptoms. Health experts predict that some 10 percent to 15 percent of these people will develop long-lasting PTSD within a year of the initial incident. While there are interventions that can help individuals avoid PTSD, there's been no reliable way to identify those most likely to need it.
That may now have changed. A multi-disciplinary team of researchers has developed a method for predicting who is most likely to develop PTSD after a traumatic emergency-room experience. Their study is published in the journal Nature Medicine.
70 data points and machine learning
Image source: Creators Collective/Unsplash
Study lead author Katharina Schultebraucks of Columbia University's Department Vagelos College of Physicians and Surgeons says:
"For many trauma patients, the ED visit is often their sole contact with the health care system. The time immediately after a traumatic injury is a critical window for identifying people at risk for PTSD and arranging appropriate follow-up treatment. The earlier we can treat those at risk, the better the likely outcomes."
The new PTSD test uses machine learning and 70 clinical data points plus a clinical stress-level assessment to develop a PTSD score for an individual that identifies their risk of acquiring the condition.
Among the 70 data points are stress hormone levels, inflammatory signals, high blood pressure, and an anxiety-level assessment. Says Schultebraucks, "We selected measures that are routinely collected in the ED and logged in the electronic medical record, plus answers to a few short questions about the psychological stress response. The idea was to create a tool that would be universally available and would add little burden to ED personnel."
Researchers used data from adult trauma survivors in Atlanta, Georgia (377 individuals) and New York City (221 individuals) to test their system.
Of this cohort, 90 percent of those predicted to be at high risk developed long-lasting PTSD symptoms within a year of the initial traumatic event — just 5 percent of people who never developed PTSD symptoms had been erroneously identified as being at risk.
On the other side of the coin, 29 percent of individuals were 'false negatives," tagged by the algorithm as not being at risk of PTSD, but then developing symptoms.
Image source: Külli Kittus/Unsplash
Schultebraucks looks forward to more testing as the researchers continue to refine their algorithm and to instill confidence in the approach among ED clinicians: "Because previous models for predicting PTSD risk have not been validated in independent samples like our model, they haven't been adopted in clinical practice." She expects that, "Testing and validation of our model in larger samples will be necessary for the algorithm to be ready-to-use in the general population."
"Currently only 7% of level-1 trauma centers routinely screen for PTSD," notes Schultebraucks. "We hope that the algorithm will provide ED clinicians with a rapid, automatic readout that they could use for discharge planning and the prevention of PTSD." She envisions the algorithm being implemented in the future as a feature of electronic medical records.
The researchers also plan to test their algorithm at predicting PTSD in people whose traumatic experiences come in the form of health events such as heart attacks and strokes, as opposed to visits to the emergency department.
What would it be like to experience the 4th dimension?
Physicists have understood at least theoretically, that there may be higher dimensions, besides our normal three. The first clue came in 1905 when Einstein developed his theory of special relativity. Of course, by dimensions we’re talking about length, width, and height. Generally speaking, when we talk about a fourth dimension, it’s considered space-time. But here, physicists mean a spatial dimension beyond the normal three, not a parallel universe, as such dimensions are mistaken for in popular sci-fi shows.
Vaccines find more success in development than any other kind of drug, but have been relatively neglected in recent decades.
Vaccines are more likely to get through clinical trials than any other type of drug — but have been given relatively little pharmaceutical industry support during the last two decades, according to a new study by MIT scholars.