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“Gravity around the black hole will shred these unlucky stars, causing them to be squeezed into thin streams and fall into the black hole,” says Vikram Ravi, assistant professor of astronomy at Caltech. “This is a really messy process. The stars don’t go quietly!” s the stars are devoured, their remains swirl around the black hole and glow with light of different frequencies, which telescopes can detect. In some cases, the stellar remains are expelled in powerful jets that shine with radio-frequency light waves....

Phobias are often irrational by nature – especially in the case of spiders, as these creatures are usually more afraid of humans than vice-versa. But: some species are a force to be reckoned with – for example, the Latrodectus spider, more commonly known as the Black Widow. It catches its prey by using venom – to be precise, latrotoxins (LaTXs), a subclass of neurotoxins, or nerve poisons. A bite from a Black Widow can be fatal for humans....

During the 181st Meeting of the Acoustical Society of America, which will be held November 29 to December 3, Shashank Sirsi, from the University of Texas at Dallas, will discuss how circulating microbubbles can be used to measure oxygen levels. The talk, “Hemoglobin Microbubbles for In Vivo Blood Oxygen Level Dependent Imaging: Boldly Moving Beyond MRI,” will take place Monday, November 29, at 11:25 a.m. Eastern U.S. at the Hyatt Regency Seattle....

“As a child, I liked to imagine what it would be like to one day wake up in someone else’s body,” says first author Pawel Tacikowski, a postdoctoral researcher at Karolinska Institutet in Sweden. “Many kids probably have those fantasies, and I guess I’ve never grown out of it — I just turned it into my job.” The team from the Brain, Body, and Self Laboratory led by Henrik Ehrsson outfitted pairs of friends with goggles showing live feeds of the other person’s body from a first-person perspective....

The same genes that promote healing after cartilage damage also appear to protect against osteoarthritis, a condition caused by years of wear-and-tear on the cartilage between joints, new research at Washington University School of Medicine in St. Louis shows. Although the research was conducted in mice, the genes also are likely to be important in people. “Our goal is to see whether we can protect cartilage in people by detecting the early biological changes that occur in osteoarthritis and prevent it from progressing to the stage where joint replacement becomes necessary,” says principal investigator Linda J....

Images taken using red, green, and blue spectral filters were combined to show the scene in natural color. The images were taken with Cassini’s wide-angle camera on June 23, 2013, at a distance of approximately 491,200 miles (790,500 kilometers) from Saturn. The Cassini spacecraft ended its mission on September 15, 2017. The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency....

In its season of “lasts,” NASA’s Cassini Spacecraft made its final close approach to Saturn’s moon Mimas on January 30, 2017. At closest approach, Cassini passed 25,620 miles (41,230 kilometers) from Mimas. All future observations of Mimas will be from more than twice this distance. This mosaic is one of the highest resolution views ever captured of the icy moon. Close approaches to Mimas have been somewhat rare during Cassini’s mission, with only seven flybys at distances of less than 31,000 miles (50,000 kilometers)....

Worldwide, the population of pet cats and dogs is growing substantially. Currently, the USA is estimated to have 76.8 million dogs and 58.4 million cats, while Brazil has 52.2 million dogs and China has 53.1 million cats. However, the environmental impact of pet diets is unclear. Marcio Brunetto and colleagues evaluated the environmental impacts – including greenhouse gas emissions, land use, and water usage – of 618 diets for dogs and 320 diets for cats in Brazil....

Over many years, astronomers have gathered data on the formation of stars in galaxies and the growth of supermassive black holes (that is, those with millions or billions of the mass of the Sun) in their centers. These data suggested that the black holes and the stars in their host galaxies grow in tandem with each other. Now, findings from two independent groups of researchers indicate that the black holes in massive galaxies have grown much faster than in the less massive ones....

When you bake a cake, you can combine the ingredients in almost any proportion, and they will still always be able to mix together. This is a little more complicated in materials chemistry. Often, the aim is to change the physical properties of a material by adding a certain proportion of an additional element; however, it isn’t always possible to incorporate the desired quantity into the crystal structure of the material....

High-resolution in-situ magnetic measurement under high pressure has been a challenge. It has limited the progress of research on the Meissner effect of superconductivity and on magnetic phase transition behavior under high pressure. Using the optically detected magnetic resonance (ODMR) technique on diamond nitrogen vacancy (NV) centers has helped in-situ detection of pressure-induced magnetic phase transitions. However, it is not convenient to analyze and interpret the measured ODMR spectra because the NV center has four axial directions and zero-field splitting is temperature dependent....

Black holes are difficult to observe, by their definition: mass concentrated in a region with a diameter so small that the resulting extremely strong gravity allows nothing to escape, not even light. Still, these objects have long found their place in astrophysics. So-called stellar black holes, in particular, with a few solar masses, are the end state of very massive stars. Now, a group of astronomers led by Kareem El-Badry (Max Planck Institute for Astronomy [MPIA] and Harvard-Smithsonian Center for Astrophysics) has used a novel method to discover the closest known black hole....

Scientists tend to view substance addiction as primarily a disease of the brain. When we enjoy sex, food, music, or hobbies, regions of our brain within the reward pathway are flooded with pleasure-inducing dopamine. Drugs like cocaine copy this effect, except up to ten times more strongly. Healthy brains aren’t at the mercy of such dopamine rushes, however: there, the prefrontal cortex weighs options and can decide to forego pleasurable activities when it’s not the time or place....

According to the standard theory, the Earth is thought to have formed from the collision of small celestial bodies known as planetesimals. Since such bodies were poor in water, Earth’s water must have been delivered either by a larger planetesimal or by a shower of smaller objects such as asteroids or comets. To trace the source of terrestrial water, researchers study isotopic ratios, and in particular the ratio in water of deuterium to hydrogen, known as the D/H ratio (deuterium is a heavier form of hydrogen)....

A comet visiting from the most distant parts of our solar system is putting on a spectacular nighttime display. Named Comet C/2020 F3 NEOWISE, the comet made its once-in-our-lifetimes close approach to the Sun on July 3, 2020, and will cross outside Earth’s orbit on its way back to the outer parts of the solar system by mid-August. The comet cruised just inside Mercury’s orbit on July 3. This very close passage by the Sun is cooking the comet’s outermost layers, causing gas and dust to erupt off the icy surface and creating a large tail of debris....

Catalase is produced naturally and used by humans, animals, and plants. Inside cells, the antioxidant enzyme kick starts the breakdown of hydrogen peroxide, which can be toxic, into water and oxygen. The enzyme is also commonly used worldwide in food production and as a dietary supplement. “There is a lot of focus on vaccines and antiviral drugs, and rightly so,” said Yunfeng Lu, a UCLA Samueli School of Engineering professor of chemical and biomolecular engineering and a senior author on the study....

In study, acetaminophen alters perceptions of risk. While acetaminophen is helping you deal with your headache, it may also be making you more willing to take risks, a new study suggests. People who took acetaminophen rated activities like “bungee jumping off a tall bridge” and “speaking your mind about an unpopular issue in a meeting at work” as less risky than people who took a placebo, researchers found. Use of the drug also led people to take more risks in an experiment where they could earn rewards by inflating a virtual balloon on a computer: Sometimes they went too far and the balloon popped....

The Columbia University Irving Medical Center (CUIMC) Newsroom interviewed Stephen Goff, Ph.D., an expert in transmissible cancers at Columbia University and a co-author of the paper, to learn more about how cancer can spread in shellfish colonies separated by thousands of miles of water, and how that could help us better understand cancer metastasis in other organisms. Wait, cancer can be contagious? Yes, but it’s a rare occurrence. So far scientists have only observed contagious cancers in three types of animals: Tasmanian devils, dogs, and shellfish....

Microalgae of the dinoflagellate group are known for their ability to survive in other animal cells. These tiny single-cell organisms have engaged in mutually beneficial relationships with corals since primeval times. By passing on critical nutrients to their hosts, dinoflagellates allow corals to thrive even in barren areas. A research team from the Centre for Organismal Studies (COS) of Heidelberg University recently discovered that such symbioses within the cell essentially depend on the ability of the algae to suppress the immune system of their host cell and thereby avoid being “spit out” again....

Clinic and hospital drug spending increased due to higher usage and new drugs; price increases remained below inflation. The COVID-19 treatment remdesivir dominated hospital drug spending in 2021, accounting for nearly 10% of all pharmaceutical expenses and outpacing the next three drugs combined, according to the ASHP (American Society of Health-System Pharmacists) National Trends in Prescription Drug Expenditures and Projections for 2022. “Drug expenditures played a significant role in the rise in healthcare expenditures sparked by the COVID-19 pandemic,” said Daniel J....