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One of the first bioelectronic devices to combine living bacteria with sensors has successfully improved healthy skin regeneration in mice with psoriasis

On July 14th, 2015, the New Horizons spacecraft conducted the first-ever flyby of Pluto, which once was (and to many, still is) the ninth planet of the Solar System. While the encounter was brief, the stunning images and volumes of data it obtained revealed a stunningly vibrant and dynamic world. In addition to Pluto’s heart, floating ice hills, nitrogen icebergs, and nitrogen winds, the New Horizons data also hinted at the existence of an ocean beneath Pluto’s icy crust. This effectively made Pluto (and its largest moon, Charon) members of the “Ocean Worlds” club.

Almost a decade after that historic encounter, scientists are still making discoveries from New Horizons data. In a new paper, planetary scientists Alex Nguyen and Dr. Patrick McGovern used mathematical models and images to learn more about the possible ocean between Pluto’s icy surface and its silicate and metallic core. According to their analysis, they determined that Pluto’s ocean is located beneath a surface shell measuring 40 to 80 km (25 to 50 mi), an insulating layer thick enough to ensure that an interior ocean remains liquid.

Nguyen is a graduate student in Earth, environmental, and planetary sciences in Arts & Sciences at Washington University in St. Louis (WUSTL), while Dr. McGovern is a Senior Staff Scientist with the Lunar and Planetary Institute (LPI) in Houston. Their paper, “The role of Pluto’s ocean’s salinity in supporting nitrogen ice loads within the Sputnik Planitia basin,” recently appeared in the journal Icarus. The study is part of Nguyen’s Ph.D. research at Washington University, where he is an Olin Chancellor’s Fellow and a National Science Foundation Graduate Research Fellow.

This cutaway image of Pluto shows a section through the area of Sputnik Planitia, with dark blue representing a subsurface ocean and light blue for the frozen crust. Artwork by Pam Engebretson, courtesy of UC Santa Cruz.

For decades, planetary scientists assumed Pluto was far too cold to support an interior ocean. Pluto orbits well beyond the Solar System’s “Frost Line,” the boundary beyond which volatile elements (water, carbon dioxide, ammonia, etc.) become solid. With an average surface temperature of -229 °C (-380°F), even nitrogen and methane become as solid as rock. As Nguyen indicated in a recent interview with The Source (WUSTL’s news site), “Pluto is a small body. It should have lost almost all of its heat shortly after it was formed, so basic calculations would suggest that it’s frozen solid to its core.”

But thanks to New Horizons, scientists were presented with multiple lines of evidence that suggest Pluto likely has an interior ocean. This includes cryovolcanoes, such as those observed on Ceres, Europa, Ganymede, Enceladus, Titan, Triton, and other “Ocean Worlds.” While the existence of this ocean is still subject to debate, the theory is gaining acceptance to the point that it is considered a very real possibility. For their study, Nguyen and McGovern created mathematical models to explain the cracks and bulges in the ice covering Pluto’s Sputnik Planitia Basin.

Their results indicate that an ocean could exist beneath an icy shell 40 to 80 km (25 to 50 mi) thick, which would be sufficient to ensure that Pluto could maintain a liquid water ocean in its interior despite surface conditions. They also calculated the likely density or salinity of the ocean based on the surface features and determined that Pluto’s ocean could be up to 8% denser than Earth’s oceans. This salinity level would make Pluto’s ocean comparable to the Great Salt Lake, the Dead Sea, and other high-salinity bodies of water on Earth.

According to Nguyen, any variations in this density (greater or lower) would be evident from the cracks and fractures in the Sputnik Platina Basin. “We estimated a sort of Goldilocks zone where the density and shell thickness is just right,” he said. If the ocean were less dense, the ice shell would collapse, leading to many more fractures in the surface. If it were denser, the ice sheet would be more buoyed, which would be evident from there being fewer fractures. Unfortunately, it could be many decades before another spacecraft reaches Pluto to help confirm these findings. In the meantime, the case for Pluto’s interior ocean grows stronger!

Further Reading: Washington University at St. Louis, Icarus

The post Pluto Has an Ocean of Liquid Water Surrounded by a 40-80 km Ice Shell appeared first on Universe Today.

The earliest black holes in the Universe called primordial black holes (PBHs), are strong contenders to help explain why the Universe is heavier than it looks. There’s only one problem: these miniature monsters haven’t exactly been observed—yet. But, when astronomers do find them, they might turn out to be part of the Universe’s dark matter component.

Primordial black holes are one of several types of highly massive objects thought to exist in the Universe. We already know about stellar-mass black holes. They form during the deaths of hugely massive stars and generally end up containing up to dozens of solar masses. Then there are the supermassive black holes, embedded in the hearts of most galaxies. They sequester up to millions of solar masses.

The intermediate-mass black holes occupy the middle of the “black hole” spectrum. They’re another hot topic in black hole research circles. Appropriately enough, the masses of these black holes are between their stellar and supermassive counterparts. All these types of massive objects can collide with each other to grow bigger black holes. That generates gravitational waves that can be detected. The “ping” of each gravitational wave tells scientists a great deal about the objects colliding, including their masses.

How we might discover primordial black holes and help solve the dark matter mystery. Credit: ESA Understanding Primordial Black Holes in Context of Cosmic History

While astronomers search for PHBs, others are looking to explain why they might be part of the dark matter component of the Universe. In addition, they could explain the origin of binary black holes detected in gravitational wave observations.

A team of researchers at the University of Tokyo examined the “problem” of PBHs. Their work suggests that there should be far fewer of these objects than current models show. But, nobody knows how many existed back then. So, astronomers search them out using gravitational wave observatories. Their discovery should open a window on conditions in the early Universe when PBH formed.

These miniature ones are fascinating to think about. “Many researchers feel they are a strong candidate for dark matter, but there would need to be plenty of them to satisfy that theory,” said graduate student and team member Jason Kristiano. “They are interesting for other reasons too, as since the recent innovation of gravitational wave astronomy, there have been discoveries of binary black hole mergers, which can be explained if PBHs exist in large numbers. But despite these strong reasons for their expected abundance, we have not seen any directly, and now we have a model which should explain why this is the case.”

Modeling the Existence of Primordial Black Holes

The big question about PHBs: do (or did) they exist? And, can they be part of the dark matter component of the Universe? To answer that, Kristiano and his advisor Jun’ichi Yokoyama, searched through models of PBH formation. The best ones do not agree with the observed conditions of the leftover light fingerprint of the Big Bang. That’s called the cosmic microwave background (CMB). This is important, since PBHs formed in very early epochs of cosmic history, soon after the Big Bang. So, the team used the best model of PBH formation and applied quantum field theory to bring the model into alignment with reality.

Yokoyama explained the background behind their work. “At the beginning, the universe was incredibly small, much smaller than the size of a single atom. Cosmic inflation rapidly expanded that by 25 orders of magnitude. At that time, waves traveling through this tiny space could have had relatively large amplitudes but very short wavelengths. What we have found is that these tiny but strong waves can translate to otherwise inexplicable amplification of much longer waves we see in the present CMB,” said Yokoyama.

“We believe this is due to occasional instances of coherence between these early short waves, which can be explained using quantum field theory, the most robust theory we have to describe everyday phenomena such as photons or electrons. While individual short waves would be relatively powerless, coherent groups would have the power to reshape waves much larger than themselves. This is a rare instance of where a theory of something at one extreme scale seems to explain something at the opposite end of the scale.”

From Fluctuations to Miniature Black Holes

Those early small-scale fluctuations Yokohama describes affect some of the larger-scale fluctuations in the cosmic microwave background. Researchers can use measurements of wavelengths in the CMB to constrain the extent of corresponding wavelengths in the early Universe. That also puts some limits on any other phenomena that rely on the shorter, stronger wavelengths. And this is where the PBHs come back in.

“It is widely believed that the collapse of short but strong wavelengths in the early universe is what creates primordial black holes,” said Kristiano. “Our study suggests there should be far fewer PBHs than would be needed if they are indeed a strong candidate for dark matter or gravitational wave events.”

The next step relies on gravitational wave observatories and other types of observations. LIGO in the U.S., Virgo in Italy and KAGRA in Japan, are cooperating in observations aimed at finding the first PHBs. The results should help refine the ideas from Yokoyama’s team about PHBs and dark matter.

For More Information

The Case of the Missing Black Holes
Constraining Primordial Black Hole Formation from Single-Field Inflation
Note on the Bispectrum and One-loop corrections in Single-field Inflation with Primordial Black Hole Formation

The post Where are All the Primordial Black Holes? appeared first on Universe Today.

A free AI-powered website helps clinicians more effectively match patients with the optimal antidepressant using big data.

Engineers have helped design a new method to make hydrogen gas from water using only solar power and agricultural waste such as manure or husks. The method reduces the energy needed to extract hydrogen from water by 600%, creating new opportunities for sustainable, climate-friendly chemical production.

A team of researchers have developed a new machine-learning method that detects hate speech on social media platforms with 88 per cent accuracy, saving employees from hundreds of hours of emotionally damaging work.

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Over the last two years, scientists have used NASA's James Webb Space Telescope to explore what astronomers refer to as Cosmic Dawn -- the period in the first few hundred million years after the big bang where the first galaxies were born.

Cultivating creativity in schools is vital for a future driven by artificial intelligence (AI). But while teachers embrace creativity as an essential 21st century skill, a lack of valid and reliable creativity tests means schools struggle to assess student achievement. Now, a new machine-learning model is providing teachers with access to high-quality, fit-for-purpose creativity tests, that can score assessments in a fraction of the time and a fraction of the cost.

Researchers combined computer simulations and transmission electron microscopy experiments to better understand the ordering mobility and formation of microstructure domains in Fe3Al alloy. They were able to correlate structural changes with heat treatment to understand how particular mechanical behavior can be achieved. This is expected to allow the superelastic properties of Fe3Al to harnessed for the 3D printing of construction materials for absorbing seismic activity.

Researchers probed the transit of cations across a nanopore membrane for the generation of osmotic energy. The team controlled the passage of cations across the membrane using a voltage applied to a gate electrode. This control allowed the cation-selective transport to be tuned from essentially zero to complete cation selectivity. The findings are expected to support the application of blue energy solutions for sustainable energy alternatives worldwide.

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Team utilizes advanced statistical techniques to project the future groundwater depletion risk.

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Lenses are used to bend and focus light. Normal lenses rely on their curved shape to achieve this effect, but physicists have made a flat lens of only three atoms thick which relies on quantum effects. This type of lens could be used in future augmented reality glasses.

Growing concern about data theft and counterfeiting has inspired increasingly sophisticated security technologies, like hologram seals, that can help verify the authenticity of currency, passports and other important documents. However, as security technologies evolve, so do the techniques criminals use to get past them. To stay one step ahead of these bad actors, researchers report that they have developed a new photopatterning technique that creates two light-reactive images on one material.

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Landing on the far side of the moon is rarely attempted, due to difficulties communicating with Earth, but China is about to try. If successful, its Chang'e 6 mission will then bring lunar samples back home

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I may have mentioned this case before, but it’s one that’s guaranteed to cause arguments, for it involves the Netherlands’ policy of allowing doctor-assisted suicide of patients with incurable and debilitating mental illness. The description is at the Free Press, and you can read about Zoraya ter Beck by clicking on the screenshot below:

The U.S, has no such policy, although the following states and countries have medical aid in dying for physical illnesses (see the Wikipedia article for notes and qualifications):

Physician-assisted suicide is legal in some countries, under certain circumstances, including Austria, Belgium, Canada, Luxembourg, the Netherlands, New Zealand, Portugal, Spain, Switzerland, parts of the United States (California, Colorado, Hawaii, Maine,Montana, New Jersey, New Mexico, Oregon, Vermont, Washington and Washington DC) and Australia (New South Wales, Queensland, South Australia,Tasmania, Victoria and Western Australia). The Constitutional Courts of Colombia, Germany and Italylegalized assisted suicide, but their governments have not legislated or regulated the practice yet.

I haven’t looked carefully at all these places to see if they allow physician-assisted suicide for the mentally ill, but as far as I know the Netherlands is unique in this respect. Canada was supposed to allow it, but has put it on hold.

Opposition to general euthanasia is often based on religion (“God will take you when it’s time”), and opposition to euthanasia for mental illness is based on the supposition that the illness may be temporary, so that people might recover and be glad they didn’t choose doctor-assisted suicide.

In my view, not only should people with any intractable illness that causes great pain should be allowed to die legally, and I don’t exempt mental illness. In fact, severe depression or bipolar disorder can be the equivalent of cancer: although mental illness might not kill you by itself, it can make life not worth living, so that death would seem to be an ethical choice for both the patient and the state. Further, at least in the Netherlands there are sufficient protections in place to ensure that a person who has a good chance of recovering will not be euthanized, and that the illness must be intractable as judged from previous medical interventions.

But I digress: click to read (it’s archived here):

The details:

Even as a child, Zoraya ter Beek had a persistent wish to die. Growing up in the quaint Dutch town of Oldenzaal, she never felt as if she fit in. At the age of 21, she was diagnosed with autism; a year later, she started wearing a “Do Not Resuscitate” tag around her neck. Last Wednesday, her wish was finally granted: after a three-year wait, Zoraya ended her life through physician-assisted suicide. She had just turned 29.

. . . .Zoraya received little or no support from her family. When she turned 18, she moved out of her childhood home to live with her boyfriend, Stein. He was ten years older than her, and her parents didn’t approve of the age difference. When I first contacted her, Zoraya had been estranged from her mother and three older sisters for six years. Her father died last year from cancer.

As a young adult, Zoraya felt unable to study, or embark on a career. She told me Stein, who is an IT programmer, was worried about how she felt, and encouraged her to get therapy. Over the course of a decade, she tried everything to relieve the symptoms of her mental illness—including, at last, 33 rounds of electroconvulsive therapy, where electric currents jolt the brain.

Zoraya’s last treatment was in August 2020, after which she says her psychiatrist told her: “There’s nothing more we can do for you. It’s never going to get any better.”

“After we heard that, we all kind of knew what that meant,” Zoraya told me, referring not only to herself but her boyfriend, her friends, and her doctors. “I was always very clear: if it doesn’t get better, I can’t do this.”

I ask you: who would insist that this young woman, in deep pain from mental illness that could not be cured or even helped, stay alive? And why?

And so Zoraya went ahead:

Earlier this month, she told The Guardian: “People think that when you’re mentally ill, you can’t think straight, which is insulting.”

“In the Netherlands,” she added, “we’ve had this law for more than 20 years. There are really strict rules, and it’s really safe.”

Zoraya had great faith in not only the law but also the medical profession.

“Doctors want to help people feel better,” she told me. “Doctors don’t become doctors to kill people, even if that’s what you’re wishing for.”

Nevertheless, Zoraya had a plan B—or, as she called it, an “escape plan”—in case her application didn’t get final approval. It was a suicide kit, which she told me she’d obtained from Exit International, an NGO that advocates for the legalization of voluntary euthanasia.

In the end, she didn’t need it. Zoraya had hoped to be euthanized on her birthday, May 2. But there had been some last-minute bureaucratic delays. Nevertheless, her assisted suicide was approved a couple of weeks ago.

Another argument against assisted suicide for the mentally ill is that it could lead to a “slippery slope,” in which people who aren’t that ill, or pretend that they’re suffering, use it as an exit when they could be cured. But although the number of cases of euthanasia for mental illness is increasing, I know the Netherlands’ criteria are sufficiently strict to halt any slope. The increasing numbers reflects, I think, the public’s increasing acceptance of euthanasia as a humane way to end a miserable life, as well as increasing dissemination of information:

The fact is an increasing number of people suffering from mental illness in the Netherlands are choosing to end their lives. Zoraya is right that the assisted dying law has been around for years, but even as recently as 2010, there were only two recorded cases of medically assisted suicide that involved psychiatric suffering. Last year, there were 138.

But Zoraya is all on board with the regulations as they are, and agrees that they should be strict. And so, with the help of a doctor, she ended her life:

Zoraya told me she didn’t want a funeral, because she didn’t think her friends would want to say goodbye. But she did want her boyfriend to be with her at the end. When I spoke to her, she described how she wanted to die:

I will take my place on the couch. [The doctor] will once again ask if I am sure, and she will start up the procedure and wish me a good journey. Or, in my case, a nice nap, because I hate it if people say, “Safe journey.” I’m not going anywhere.

On Wednesday, a friend of hers posted an announcement on X: “Zoraya passed away today at 1:25 p.m. Or as she saw it herself: she went to sleep.”

Few details of her death have been reported—except that her boyfriend was at her side.

It’s sad to envision this, but we are not at the point where conditions like Zoraya’s can be treated. But again, who can gainsay that she did what was best for her? Who could be so churlish as to say she must stay alive.

The answer: the faithful.

If you want to see religious jobs who argue that prayer and recognize the value of suffering should have kept her alive, read this article in the Catholic Herald: “Zoraya ter Beek deserved doctors who cherished her life as precious.”  A quote from that:

As Catholics, we have a powerful message to tell that there is value to be found in suffering: when we step into church, we are met with the sight of Christ crucified, and are reminded of the agony he bore because he loved us. In fact, it’s because Christ experienced being human that we can be sure that he understands and cares for us in our suffering. Still, most of us are not lawmakers. We’re not campaigners or politicians. Trying to justify our Catholic beliefs to the world can seem overwhelming – almost pointless, when our faith is so often denigrated.

As Catholics, we must continue to remind ourselves of the power of prayer; not exclusively praying for a change of heart of those in positions of power who may choose to legalise assisted dying, though that is of course important, but rather praying in order to cultivate closeness to God in our own lives. We must rely on God first, and only then can we show others that we can help them bear their pain. We must confide in the one who bore the greatest pain for us, and petition, in prayer, to be given the strength to imitate his goodness and his compassion in our own lives. Finally, we must never lose hope, even in cases where a person appears determined to die. We must pray for them to the very end, for by God’s grace, no soul is ever truly beyond saving.

This is the maliciousness of religion: keep the suffering going, for superstition tells us that God will make it all right in the end.  It’s horrible.

Here she is in a video made by The Free Press: