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Physicists have shown that ultra-thin two-dimensional materials such as tungsten diselenide can rotate the polarization of visible light by several degrees at certain wavelengths under small magnetic fields suitable for use on chips.

Atrial fibrillation is the most common cardiac arrhythmia worldwide with around 59 million people concerned in 2019. This irregular heartbeat is associated with increased risks of heart failure, dementia and stroke. It constitutes a significant burden to healthcare systems, making its early detection and treatment a major goal. Researchers have recently developed a deep-learning model capable of predicting the transition from a normal cardiac rhythm to atrial fibrillation. It gives early warnings on average 30 minutes before onset, with an accuracy of around 80%. These results pave the way for integration into wearable technologies, allowing early interventions and better patient outcomes.

The study highlights the rapid progress and transformative potential of AI in weather prediction.

Magnetic two-dimensional materials consisting of one or a few atomic layers have only recently become known and promise interesting applications, for example for the electronics of the future. So far, however, it has not been possible to control the magnetic states of these materials well enough. A research team is now presenting an innovative idea that could overcome this shortcoming -- by allowing the 2D layer to react with hydrogen.

Magnetic two-dimensional materials consisting of one or a few atomic layers have only recently become known and promise interesting applications, for example for the electronics of the future. So far, however, it has not been possible to control the magnetic states of these materials well enough. A research team is now presenting an innovative idea that could overcome this shortcoming -- by allowing the 2D layer to react with hydrogen.

Lithium salts make batteries powerful but expensive. An ultralow-concentration electrolyte based on the lithium salt LiDFOB may be a more economical and more sustainable alternative. Cells using these electrolytes and conventional electrodes have been demonstrated to have high performance. In addition, the electrolyte could facilitate both production and recycling of the batteries.

Simulated effects of microgravity significantly affect rhythmicity and sleep in humans, a new study finds. Such disturbances could negatively affect the physiology and performance of astronauts in space.

Superradiant atoms can help us measure time more precisely than ever. In a new study, researchers present a new method for measuring the time interval, the second, mitigating some of the limitations that today's most advanced atomic clocks encounter. The result could have broad implications in areas such as space travel, volcanic eruptions and GPS systems.

State-of-the-art artificial intelligence systems known as large language models (LLMs) are poor medical coders, according to researchers. Their study emphasizes the necessity for refinement and validation of these technologies before considering clinical implementation. The study extracted a list of more than 27,000 unique diagnosis and procedure codes from 12 months of routine care in the Mount Sinai Health System, while excluding identifiable patient data. Using the description for each code, the researchers prompted models from OpenAI, Google, and Meta to output the most accurate medical codes. The generated codes were compared with the original codes and errors were analyzed for any patterns.

Based on radio telescope data and models of black hole physics, a team has used neural networks to reconstruct a 3D image that shows how explosive flare-ups in the disk of gas around our supermassive black hole might look.

"Advanced recycling" promises to convert dirty, mixed waste plastic into brand new plastic time and time again. It is a major step towards creating a circular economy and fighting climate change

The finding that managed fires burn a much greater area than thought means we may be underestimating the increase in wildfires due to global heating

Forensic investigators can reliably measure drug and explosive residue using gels that lift fingerprint samples

I recently received the following question to the SGU e-mail:

“I have had several conversations with friends/colleagues lately regarding indigenous beliefs/stories. They assert that not believing these based on oral histories alone is morally wrong and ignoring a different cultures method of knowledge sharing. I do not want to be insensitive, and I would never argue this point directly with an indigenous person (my friends asserting these points are all white). But it really rubs me the wrong way to be told to believe things without what I would consider more concrete evidence. I’m really not sure how to comport myself in these situations. I would love to hear any thoughts you have on this topic, as I don’t have many skeptical friends.”

I also frequently encounter this tension, between a philosophical dedication to scientific methods and respect of indigenous cultures. Similar tensions come up in other contexts, such as indigenous cultures that hunt endangered species. These tensions are sometimes framed as “decolonization” defined as “the process of freeing an institution, sphere of activity, etc. from the cultural or social effects of colonization.” Here is a more detailed description:

“Decolonization is about “cultural, psychological, and economic freedom” for Indigenous people with the goal of achieving Indigenous sovereignty — the right and ability of Indigenous people to practice self-determination over their land, cultures, and political and economic systems.”

I completely understand this concept and think the project is legitimate. To “decolonize” an indigenous culture you have to do more than just physically remove foreign settlers. Psychological and cultural colonization is harder to remove. And often cultural colonization was very deliberate, such as missionaries spreading the “correct” religion to “primitive” people.

But like all good ideas, it can be taken too far. People tend to prefer the moral clarity of simplistic dichotomies. What the e-mailer is referring to is when science is considered part of colonization, and something that indigenous people should free themselves of. Further, we need to respect their cultural freedom from science and accept their historical view of reality as being just as legitimate as a science-based one. But I think this approach is completely misguided, even if it is well-intentioned (well intentioned but misguided is often a dangerous combination).

There are a couple of ways to look at this. One is that science is not a cultural belief. Science (and philosophy, for that matter) is something that transcends culture. The purpose of science is to transcend culture, to use a set of methods that are as objective as possible, and to eliminate bias as much as possible. In fact, scientists often have to make a deliberate effort to think outside of the biases of their own culture and world view.

Logic and facts are not cultural. Reality does not care about our own belief systems, whatever their origin, it is what it is regardless. Respecting an indigenous culture does not mean we must surrender respect for facts and logic.

Another important perspective, I think, is that as a species we have some shared culture and knowledge. This is actually a very useful and even beautiful thing – there is human culture and knowledge that we can all share, and I would put science at the top of that list. There are objective methods we can use to come to mutual agreement despite our differing cultures and histories. We can have the commonality of a shared reality, because that reality actually exists (whether we believe in it or not) and because the scientific methods we use to understand that reality are transcultural. Science, therefore, is not one culture colonizing another, but all cultures placing something objective and verifiable above their own history, culture, and parochial perspectives.

We can make similar arguments for certain basic aspects of ethics and morality, although this is more difficult to achieve universal objectivity. But as a species we can conclude that certain things are objectively ethically wrong, such as slavery. If an indigenous culture believed in and actively practiced human slavery, would we be compelled to respect that and look the other way?

Yet another layer to this discussion is consideration of the methods that are used by one society to convince another to adopt its norms. If it is done by force, that is colonization. If it is done by intellectual persuasion and adopted freely, that is just one group sharing its knowledge with another.

And finally, I think we can respect the mythology and beliefs of another culture without accepting those beliefs as objectively true, or abandoning all concept of “truth” and pretending that all knowledge is equal and relative. Pretending the ancient cultural beliefs of a group are “true” is actually infantilizing and racist, in my opinion. It assumes that they are incapable of reconciling what every culture has had to reconcile to some degree – the difference between historical beliefs and objective evidence. Every society has their narratives, their view of history, and facts invariably push up against those narratives.

I know that in practice these principles are very complex and there is a lot of gray zone. Science is an ideal, and people have a tendency to exploit ideals to promote their own agenda. Just labeling something science doesn’t mean we can bulldoze over other considerations, and science is often corrupted by corporate interests, and cultural promotion, even to the point of hegemony. This is because the people who execute science are flawed and biased. But that does not change the ideal itself. Science and philosophy (examining arguments for internal logical consistency) are methods we can use to arrive at transcultural human beliefs and institutions.

Let’s take the World Health Organization (WHO), for example, which is an international organization dedicated to promoting health around the world. I would argue, as an international organization, they should be relying on objective science-based methods as much as possible. Also, since their goal is to improve the health of humanity, science is the best way to do that. They should not, in my opinion, bow down before any individual culture’s pre-scientific beliefs about health for the purpose of cultural sensitivity. It is not their mission to promote local cultures or to right the wrongs of past colonizers. They should unapologetically take the position that they will only promote and use interventions that are based on objective scientific evidence. They can still do this in a culturally sensitive way. All physicians need to practice “culturally competent” medicine, which does not have to include endorsing or using treatments that do not work.

So in practice this is all very messy, but I think it’s important to at least following legitimate guiding principles. Science is something that all of humanity owns, and it strives towards an ideal that it is transcultural and objective. This is not incompatible with respecting local cultures and self-determination.

 

The post Indigenous Knowledge first appeared on NeuroLogica Blog.

Shading the planet by spraying aerosols into the stratosphere might stave off ice sheet collapse, modelling studies suggest, but we are running out of time

Astronauts on board the International Space Station are often visited by supply ships from Earth with food among other things. Take a trip to Mars or other and the distances are much greater making it impractical to send fresh supplies. The prepackaged food used by NASA loses nutritional value over time so NASA is looking at ways astronauts can produce nutrients. They are exploring genetic engineering techniques that can create microbes with minimal resource usage. 

Many of us take food and eating for granted. The food we can enjoy is usually flavoursome and the textures varied. Astronauts travelling through space generally rely upon pre-packaged food and often this can lack the taste and textures we usually enjoy. Lots of research has gone into developing a more pleasurable dining experience for astronauts but this has usually concentrated on short duration trips. 

The space station’s Veggie Facility, tended here by NASA astronaut Scott Tingle, during the VEG-03 plant growth investigation, which cultivated Extra Dwarf Pak Choi, Red Russian Kale, Wasabi mustard, and Red Lettuce and harvested on-orbit samples for testing back on Earth. Credits: NASA

During longer term missions, astronauts will have to grow their own food. Not only due to the nutritional issues that form the purpose of this article but carrying prepackaged food for flights that last many years becomes a logistic challenge and a launch overhead. To address the loss of nutritional values, the Ames Research Centre’s Space Biosciences Division has launched its BioNutrients project to enable future space travellers to grow their own supplements.

The team has announced they has come up with a solution, thanks to the wonders of genetic engineering. The approach that the team has developed involves microbial based food (similar to yeast) that can produce nutrients and compounds with small amounts of resources. 

The secret is to store dried microbes and take food grade bioreactors along on the trip. Until now I never knew what a bioreactor was nor that they even existed. I live in the world of physics and astrophysics so this concept intrigued me. Turns out that a bioreactor does just what it says. It is a container of some form, often made from steel inside which, a biologically active environment can be maintained. Often chemical processes are carried out inside which involve organisms undergoing either aerobic or anaerobic processes. They are often used to grow cells or tissues and it is within these that NASA pins their hopes on cultivating food in space. 

Even years after departure, the dried out microbes can be rehydrated many years later and cultured inside the bioreactor, creating the nutrients astronauts need. To date, the team has managed to produce carotenoids (a pigment found in nature) which are used for antioxidants, follistatin for muscle loss and yogurt and kefir to keep the gut in good health. The real challenge though is making food that the astronauts will want to eat. 

Source : BioNutrients Flight Experiments

The post Astronaut Food Will Lose Nutrients on Long-Duration Missions. NASA is Working on a Fix appeared first on Universe Today.

No matter how implausible it is or how weak the evidence for it is, the myth that COVID vaccines cause "turbo cancer" just won't die. Quite the contrary, alas. Antivaxxers are—dare I say?—turbocharging it with bad science.

The post COVID-19 vaccine-caused “turbo cancer” nonsense just keeps getting more turbocharged and nonsensical first appeared on Science-Based Medicine.

A surprise appearance of a new comet made the April 8th total solar eclipse all the more memorable.

Any dedicated ‘umbraphile’ will tell you: no two eclipses are exactly the same. Weather, solar activity, and the just plain expeditionary nature of reaching and standing in the shadow of the Moon for those brief moments during totality assures a unique experience, every time out. The same can be said for catching a brief glimpse of what’s going on near the Sun, from prominences and the pearly white corona to the configuration of bright planets… and just maybe, a new comet.

The Discovery

While many planned to try and spy periodic Comet 12P Pons-Brooks during totality, astronomer Karl Battams at the U.S. Naval Observatory alerted us to another possibility. A new sungrazing comet, spotted just hours prior. The Kreutz family comet was seen by Worachate Boonplod in the field of view of the joint NASA/ESA Solar Heliospheric Observatory’s (SOHO) LASCO C3 and C2 imagers. These are equipped with Sun-covering coronagraphs that allow it to see the near solar environment. The mission was launched over a quarter of a century ago in 1995. SOHO was deployed to the sunward L1 Earth-Sun Lagrange point nearly a million miles distant. SOHO has since proven itself to be a crucial workhorse in solar heliophysics.

Doomed SOHO-5008 (lower left). Credit: NASA/ESA/SOHO

The comet soon received the formal designation of SOHO-5008. That’s right: SOHO has led to the discovery of over 5,000 comets in its career. Most of these discoveries were thanks to the efforts of dedicated online sleuths, scouring recent LASCO images.

At the time, the doom’d comet was a faint object, located only a few degrees from the Sun. The icy interloper was a tough target to nab during the fleeting minutes of totality, but at least two dedicated astrophotographers managed to catch it. Lin Zixuan saw it imaging from northern New Hampshire. Petr Horálek from the Institute of Physics in Opava Czechia (Czech Republic) was imaging from Mexico as he caught the object.

Like so many other sungrazers, the comet met its demise shortly after discovery (less than 12 hours, in fact), like a sundiving spaceship at a Disaster Area concert right out of Douglas Adam’s Hitchhiker’s Guide to the Galaxy.

A Brief History of Sungrazers

This sort of SOHO versus comet, versus eclipse discovery has only occurred twice: once in 2008 and again in 2020). SOHO wasn’t designed per se to find comets, but its prolific nature as a comet hunter has become an essential part of the legacy of the mission. SOHO has defined whole new families of Kreutz, Marsden and Kracht sungrazing comets. And to think, prior to the mission, only sixteen sungrazing comets were even known of.

One similar case was the Great Comet of 1948, which was also discovered by stunned observers during a total solar eclipse. Another was C/1965 Ikeya-Seki, which went on to become one of the truly great comets of the 20th century. More recently, C/2011 W3 Lovejoy surprised everyone by surviving its perihelion passage 140,000 kilometers from the surface of the Sun. Just one year later, however, 2012 S1 ISON didn’t.

It was a thrilling celestial spectacle, with an added treat.

The post There Was a Doomed Comet Near the Sun During the Eclipse appeared first on Universe Today.

An Australian bull ant is the first animal known to use the patterns produced by polarised moonlight to navigate its environment

I really can’t believe that the Ingenuity helicopter on Mars took its maiden voyage in April 2021. On the 16th April 2024, engineers at NASA have received the final batch of data from the craft which marks the final task of the team. Ingenuity’s work is not over though as it will remain on the surface collecting data. For the engineers at NASA, they have their sights set on Dragonfly, a new helicopter destined for Titan.

When Ingenuity took off on its maiden voyage it became the first powered craft to achieve flight on an alien world. It has completed 128.8 minutes of flight covering 17 kilometres. It has extra large rotor blades to achieve lift in the thin martian atmosphere and has performed excellently providing guidance and targets for the Perseverance Rover to study close up. 

Ingenuity helicopter

It’s surprising to think that Ingenuity was only ever designed to be a short-lived demonstration mission. Over a period of 30 days, Ingenuity was to perform five experimental test flights and operate over three years. Unfortunately a rather hard landing damaged its rotor blades rendering it unable to fly again. It’s now sat at Airfield Chi in the now named “Valinor Hills” area of Mars. The team gave the region the nickname as a homage to the final residence of the immortals in Lord of the Rings. 

With Ingenuity now unable to fly the team had sent a software update to direct it to continue to collect data even if the Rover is unavailable. This will mean that it will wake each morning, test the (non-flight) systems are operational, take a colour image of the surface and record the temperature. The team believe such long term data could help to inform martian weather studies and help future explorers. This is a long term purpose for Ingenuity and it has the capability to store data for 20 years! If system or battery failure occurs the data will still be securely stored. The only way to retrieve the data though, will be through another autonomous craft or a human visitor of the future. 

The success of Ingenuity paved the way for a new era of planetary exploration. Next up is Dragonfly, a mission to Saturn’s moon Titan. Costing a total of $3.35 billion across its entire lifecycle it will become the fourth mission in NASA’s New Frontiers Program. The probe will be managed by the Marshall Space Flight Centre but behind them is an international team from many different organisations including but not limited to Goddard Space Flight Centre in Maryland; Penn State University in State College, Pennsylvania; Centre National d’Etudes Spatiales in Paris; the German Aerospace Centre in Cologne, Germany; and JAXA (Japan Aerospace Exploration Agency) in Tokyo.

Artist’s concept of Dragonfly soaring over the dunes of Saturn’s moon Titan. Credit: NASA/Johns Hopkins APL/Steve Gribben

Dragonfly is slated to arrive in 2034. It’s mission will be to visit multiple locations, sampling the minerals to search for prebiotic chemical processes. It will also look for chemical signatures that indicate water-based and/or hydrocarbon-based life. Unlike Ingenuity, its rotors are similar size to those you would find on a drone on Earth. The atmosphere is thick and so there is no need for super-sized blades. 

Source : NASA’s Ingenuity Mars Helicopter Team Says Goodbye … for Now and NASA’s Dragonfly Rotorcraft Mission to Saturn’s Moon Titan Confirmed

The post The Ingenuity Team Downloads the Final Data from the Mars Helicopter. The Mission is Over appeared first on Universe Today.