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Diverse and inclusive teams are not merely a moral imperative but also a catalyst for scientific excellence in robotics, scientists point out in a study. The team has outlined how a scientific community can benefit if its leadership fosters an environment of diversity and inclusion, and propose a leadership guide for roboticists to help reap these benefits.

Diverse and inclusive teams are not merely a moral imperative but also a catalyst for scientific excellence in robotics, scientists point out in a study. The team has outlined how a scientific community can benefit if its leadership fosters an environment of diversity and inclusion, and propose a leadership guide for roboticists to help reap these benefits.

A study by a team of scientists finds that AI systems are also prone to social identity biases, revealing fundamental group prejudices that reach beyond those tied to gender, race, or religion.

Copper-oxide (CuO2) superconductors, such as Bi2Sr2CaCu2O8+ (Bi2212), have unusually high critical temperatures. Optical reflectivity measurements of Bi2212 have shown that it exhibits strong optical anisotropy. However, this has not been studied through optical transmittance measurements, which can offer more direct insights into bulk properties. Now, researchers have elucidated the origin of this optical anisotropy through ultraviolet and visible light transmittance measurements of lead-doped Bi2212 single crystals, enabling a more precise investigation into its superconductivity mechanisms.

Copper-oxide (CuO2) superconductors, such as Bi2Sr2CaCu2O8+ (Bi2212), have unusually high critical temperatures. Optical reflectivity measurements of Bi2212 have shown that it exhibits strong optical anisotropy. However, this has not been studied through optical transmittance measurements, which can offer more direct insights into bulk properties. Now, researchers have elucidated the origin of this optical anisotropy through ultraviolet and visible light transmittance measurements of lead-doped Bi2212 single crystals, enabling a more precise investigation into its superconductivity mechanisms.

Ferrocene is a key molecule for developing molecular machines. However, it readily decomposes on the surface of flat noble metal substrates, marking a significant challenge. Now researchers have stabilized ferrocene by linking it with ammonium salts and trapping them in a molecular film made up of cyclic crown ether molecules. The ammonium-linked molecule performs reversible lateral sliding motion upon the application of electrical voltage, representing the smallest molecular machine.

A researcher has developed a new technique to detect long wave infrared (LWIR) photons of different wavelengths or 'colors.' The new detection and imaging technique will have applications in analyzing materials by their spectral properties, or spectroscopic imaging, as well as thermal imaging applications.

Non-reciprocal interactions can increase the order in an active system. The researchers created a model to describe the emerging patterns depending on the amount of non-reciprocity in an active system.

Researchers have developed a 3D-printed device that generates twisting light beams with orbital angular momentum (OAM), a form of rotational energy that can carry more data than regular beams.

Researchers have developed a 3D-printed device that generates twisting light beams with orbital angular momentum (OAM), a form of rotational energy that can carry more data than regular beams.

Researchers have successfully developed a deep learning model that classifies pancreatic ductal adenocarcinoma (PDAC), the most common form of pancreatic cancer, into molecular subtypes using histopathology images. This approach achieves high accuracy and offers a rapid, cost-effective alternative to current methods that rely on expensive molecular assays. The new study holds promise to advance personalized treatment strategies and improve patient outcomes.

Researchers have unlocked a new method for producing one class of 2D material and for supercharging its magnetic properties.

The future of breast cancer screening and risk-reducing strategies is being shaped by artificial intelligence (AI), according to a recent review article.

The future of breast cancer screening and risk-reducing strategies is being shaped by artificial intelligence (AI), according to a recent review article.

Theoretical physicists along with an experimental team have found evidence of a quantum spin liquid in a material known as pyrochlore cerium stannate. They achieved this by combining state-of-the-art experimental techniques, including neutron scattering at extremely low temperatures, with theoretical analysis. By measuring the way in which neutrons interact magnetically with the electron spin in pyrochlore, the researchers observed the collective excitations of spins interacting strongly with light-like waves.

The Earth and Moon have been locked in a gravitational dance for billions of years. Each day, as the Earth turns, the Moon tugs upon the oceans of the world, causing the rise and fall of tides. As a result, the Earth’s day gets a little bit longer, and the Moon gets a little more distant. The effect is small, but over geologic time it adds up. About 620 million years ago, a day on Earth was only 22 hours long, and the Moon was at least 10,000 km closer than it is now.

Evidence for this evolving dance in the geological record only goes back about two billion years. Beyond that, the Earth was so very different that there simply isn’t enough evidence to gather. So, instead, we must rely on computational models and our understanding of dynamics. We know that when the Earth formed, it had no large moon. Then, about 4.4 billion years ago, a Mars-sized protoplanet named Theia collided with our world to create the Earth-Moon system. What’s interesting is that most of the computer simulations for this collision generate a Moon that is much closer to the Earth than we’d expect. Early Earth didn’t have vast oceans, so there were no water tides to drive the Moon to a larger orbit. So how did the Moon get to its present distance?

The potential structure of a lava planet. Credit: Farhat, et al

A new study argues that back then the Earth did have tides, but they were made of lava, not water. Just after the Great Collision, Earth would have been covered in an ocean of hot lava. With the Moon so near, the lava would have experienced strong tides. Since lava is much denser than water, the effects of the tide would have been much greater. The Earth’s rotation would have slowed down much faster, and the Moon would quickly become more distant. Based on their simulations, the authors argue that the Moon’s distance would have increased by 25 Earth-radii in just 10,000 to 100,000 years. This would explain how the Moon moved towards its present distance range rather quickly.

The idea of tides on an ocean world also has implications for planets around other stars. Planets that form very close to their sun would be extremely hot, and many of them could have lava oceans for a billion years or more. Simulations of such worlds show that lava tides would accelerate the spin dynamics of such a world and could cause them to become tidally locked on a million-year timescale instead of a billion-year timescale. If this model is correct, it would have a significant impact on potentially habitable worlds. Most exoplanets orbit red dwarf stars, since red dwarfs make up about 75% of the stars in our galaxy. The habitable zone of red dwarfs is very close to the star, meaning that many of them would have begun as lava worlds. This would mean most potentially habitable worlds would have one side always facing the sun, while the other side is forever in the cold. Life on these worlds would be very different from what we see on Earth.

Reference: Farhat, Mohammad, et al. “Tides on Lava Worlds: Application to Close-in Exoplanets and the Early Earth-Moon System.” arXiv preprint arXiv:2412.07285 (2024).

The post Early Earth's Oceans of Magma Accelerated the Moon's Departure appeared first on Universe Today.

Wildlife photos return today, but I have precious few batches in the tank. If you got ’em, please send ’em, lest this feature disappear.

Today UC Davis mathematician Abby Thompson, who survived cancelation, is back with pictures of California tide pools. Abby’s captions are indented, and you can enlarge the photos by clicking on them.

November-December tidepools (Northern California).  The weather at the coast over the Thanksgiving weekend was spectacular- sunny, warm, with no wind; perfect for poking around in the tide pools.    As usual I got help with some of the IDs from people on inaturalist.

Mussel-covered rock (probably Mytilus californianus); I liked the pattern made on the sand as the tide retreated:

Calliostoma ligatum (blue-ringed top snail):

Eupentacta quinquesemita (stiff-footed sea cucumber) Probably; it’s a little hard to tell with sea cucumbers. This one was a couple of inches long.

Hemigrapsus nudus (Purple shore crab). This is one of the most common crabs on this stretch of shore.   This one was small (maybe 2” across the back) but testy, apparently ready to take me on:

Dendronotus subramosus (nudibranch). Nudibranchs are often scarce at this time of year, but the calm sea seems to have brought them out:

Phidiana hiltoni (nudibranch) Posing for the camera:

Anthopleura artemisia (moonglow anemone). I’ve posted a few pictures of this species.   The color varies so much that they all look quite different.   I’ve never seen one that’s blue before; it was striking next to the brilliant orange sponge:

Hermissenda opalescens: (nudibranch):

Cervus canadensis nannodes (Tule elk) from tiny creatures to large (although this species is small for elk). This picture is from Point Reyes National Seashore, where there’s a reserve.    A short, highly recommended hike takes you to where the elk can be found wandering about:

Tomales Point at sunset, as the tide was beginning to turn:

Camera info:  Mostly Olympus TG-7, in microscope mode, pictures taken from above the water.    The last two pictures were taken with my iphone.

Why does news reporting of science and technology have to be so terrible at baseline? I know the answers to this question – lack of expertise, lack of a business model to support dedicated science news infrastructure, the desire for click-bait and sensationalism – but it is still frustrating that this is the case. Social media outlets do allow actual scientists and informed science journalists to set the record straight, but they are also competing with millions of pseudoscientific, ideological, and other outlets far worse than mainstream media. In any case, I’m going to complain about while I try to do my bit to set the record straight.

I wrote about nuclear diamond batteries in 2020. The concept is intriguing but the applications very limited, and cost likely prohibitive for most uses. The idea is that you take a bit of radioactive material and surround it with “diamond like carbon” which serves two purposes. It prevents leaking of radiation to the environment, and it capture the beta decay and converts it into a small amount of electricity. This is not really a battery (a storage of energy) but an energy cell that produces energy, but it would have some battery-like applications.

The first battery based on this concept, capturing the beta decay of a radioactive substance to generate electricity, was in 1913, made by physicist Henty Moseley. So year, despite the headlines about the “first of its kind” whatever, we have had nuclear batteries for over a hundred years. The concept of using diamond like carbon goes back to 2016, with the first prototype created in 2018.

So of course I was disappointed when the recent news reporting on another such prototype declares this is a “world first” without putting it into any context. It is reporting on a new prototype that does have a new feature, but they make it sound like this is the first nuclear battery, when it’s not even the first diamond nuclear battery.  The new prototype is a diamond nuclear battery using Carbon-14 and the beta decay source. They make diamond like carbon out of C-14 and surround it with diamond like carbon made from non-radioactive carbon. C-14 has a half life of 5,700 years, so they claim the battery lasts of over 5,000 years.

The previous prototype nuclear diamond batteries used Nickle 63, including this Chinese prototype from earlier this year, and the one from 2018. So sure, it’s the first prototype using C-14 as the beta decay source. But that is hardly clear from the reporting, nor is there any mentions of other nuclear batteries and previous diamond nuclear batteries.

But worse, the reporting says explicitly this technology could replace the alkaline or lithium ion batteries you currently use in your devices. This will likely never be the case, for a simple reason – these devices have an extremely low energy density and specific energy. The current generated by these small diamond batteries is tiny –  on the order of 10 microwatts per cubic centimeter (called the power density). So you would need a 100 liter volume battery to produce one watt, which is about what a cell phone uses (depending on which features you are using).

But wait, that is for Ni63, which has a half life of 101.2 years. C14 has a half life of 5,700 years, which means it would produce about 56 times less current for 56 time longer per a given mass. This is just math and is unavoidable. So using a C14 battery you would need about 5,600 liters of battery to power a cell phone. They don’t mention that in the reporting.

This does not mean there are no potential applications for such batteries. Right now they are mainly used for deep space probes or satellites – devices that we will never be able to recharge or service and may need only a small amount of energy. Putting cost aside, there are some other applications feasible based on physics. We could recycle C14 from nuclear power plants and make them into diamond batteries. This is a good way to deal with nuclear waste, and it would produce electricity as a bonus. Warehouses of such batteries could be connected to the grid to produce a small amount of steady power. A building that is 100 meters by 100 meters by 20 meters tall, if it was packed with such batteries, could product about 35 Watts of power. Hmmm – probably not worth it.

The low power density is just a deal killer for any widespread or large application. You would have to use very short half-life materials to get the power density up, but then of course the lifespan is much shorter. But still, for some applications, a battery with a half-life of a few years would still be very useful.

Another potential application, however is not as a primary power source but as a source to trickle charge another battery, that has a much higher power density. But again, we have the question – is it worth it? I doubt there are many applications outside NASA that would be considered cost effective. Still, it is an interesting technology with some potential applications, just mostly niche. But reporters cannot help by hype this technology as if you are going to have everlasting cell phone batteries soon.

The post Diamond Batteries Again first appeared on NeuroLogica Blog.

Quickie with Bob: Atomic Scale Precision; News Items: Innate Morality, New Space Station, Climate Hot Spots, Orcas Wearing Hats, Evidence Against Water on Venus; Who's That Noisy; Your Questions and E-mails: Fisher Scream, CT UFO; Science or Fiction

La Niña conditions are expected to lead to a slightly cooler average global surface temperature in 2025, though it does not mean the planet as a whole has stopped warming