143 articles from WEDNESDAY 4.1.2023

It just got harder to question the existence of black holes

No notion in physics may be more mind bending than a black hole, an infinitesimal pit in spacetime whose gravity is so strong that nothing can escape. But could very dense, dark objects be masquerading as black holes? A new study suggests not. Simulations show how any material object dense enough to resemble a black hole would be unstable, either puffing up into something less dense or...

'Veggie' dinosaurs differed in how they ate their food

Although most early dinosaurs were vegetarian, there were surprising differences in the way that these animals tackled eating a plant-based diet, according to a new study by scientists from the Natural History Museum and the Universities of Bristol and Birmingham.

Eye-tracking marketing research boosts public transportation agency's ridership

One of Florida's largest passenger rail services is experiencing an increase in ridership—and leaders of a Florida Department of Transportation program that promotes alternatives to commuters who drive alone attribute some of this success to guidance from an interdisciplinary team of researchers at USF who combined eye-tracking technology and social marketing to improve the impact of marketing...

Climate change could cause 'disaster' in the world's oceans, say scientists

Climate-driven heating of seawater is causing a slowdown of deep circulation patterns in the Atlantic and Southern oceans, according to Earth system scientists at the University of California, Irvine, and if this process continues, the ocean's ability to remove carbon dioxide from the atmosphere will be severely limited, further exacerbating global warming.

Study shows hydroponic systems as a promising method for sustainable saffron production

Saffron (Crocus sativus) is a geophyte perennial plant from the family Iridaceae with underground soft corms. The stigmas of the saffron flower have been cultivated as a spice for at least 3,500 years. Conventional cultivation processes, such as planting, flower harvesting, and separation of the stigmas, are labor-intensive and time-consuming. The labor costs and low supply contribute to the high...

Researchers detect fluoride in water with new simple color change test

Environmental contaminants like fluoride, lead and pesticides exist all around and even within us. While researchers have simple ways to measure concentrations of such contaminants inside lab environments, levels are much more difficult to test in the field. That's because they require costly specialized equipment.

Climate change could cause 'disaster' in the world's oceans

Climate change will slow down deep overturning ocean circulation in the coming centuries. Using three dozen Earth system models, researchers have concluded that the Southern Meridional Overturning Circulation could completely shut down by 2300, causing disaster to the marine ecosystem on a large portion of the planet.

New type of entanglement lets scientists 'see' inside nuclei

Nuclear physicists have found a new way to use the Relativistic Heavy Ion Collider (RHIC) to see the shape and details inside atomic nuclei. The method relies on particles of light that surround gold ions as they speed around the collider and a new type of quantum entanglement that's never been seen before.

Climate risk insurance can effectively mitigate economic losses

Global warming is expected to lead to an accumulation of particularly intense hurricanes in the United States. This may substantially increase the economic losses caused by these storms. Better insurance could effectively mitigate the climate change-induced increase in economic losses. This is shown in a new study examining the effectiveness of climate risk insurance in the US.

What's Up: January 2023 Skywatching Tips from NASA

What are some skywatching highlights in January 2023? Some lovely groupings this month include the Moon with Mars, and later with Jupiter, and a close conjunction of Venus and Saturn. The brilliant stars of the Northern Hemisphere's winter sky are a dazzling sight all month long. And a comet discovered last March makes its closest approach to Earth in January, gracing pre-dawn skies....

Breakthroughs made as scientists sequence the genomes of endangered sharks

The first chromosome level genome sequences for great hammerhead and shortfin mako sharks have shown that both species have experienced major population declines over a 250,000-year history. Low genetic diversity and signs of inbreeding are concerning for Critically Endangered great hammerhead sharks, whose overfished populations have plummeted. With higher levels of genetic diversity, shortfin...

Here today, gone tomorrow: How humans lost their body hair

Orangutans, mice, and horses are covered with it, but humans aren't. Why we have significantly less body hair than most other mammals has long remained a mystery. But a first-of-its-kind comparison of genetic codes from 62 animals is beginning to tell the story of how people—and other mammals—lost their locks.

Researchers reveal how geminiviruses cause devastating disease in worldwide crops

Geminiviruses are a group of single-stranded circular plant DNA viruses that cause devastating diseases in many economically important crops including tomato, tobacco, cotton, corn, wheat, beans, and cassava worldwide. Due to their small genome size and limited coding capacity, geminiviruses rely heavily on host plants to complete their life cycle by exploiting/manipulating host components at...

Consumer preferences for sustainably produced meat and meat substitutes in Japan

Meat has multiple nutritional benefits and is consumed as the primary source of protein by an increasing segment of the world's population. However, there have been significant environmental costs associated with the growing demand for meat. The Food and Agriculture Organization of the United Nations (FAO) reported in 2013 that livestock production accounts for 14.5% of all greenhouse gas...

Climate risk insurance can effectively mitigate economic losses

Global warming is expected to lead to an accumulation of particularly intense hurricanes in the United States. This may substantially increase the economic losses caused by these storms. Better insurance could effectively mitigate the climate change-induced increase in economic losses. This is shown in a new study by the Potsdam Institute for Climate Impact Research examining the effectiveness of...

Extensive testing shows dogs' tails are not used for stabilization

A team of researchers from the Max Planck Institute for Intelligent Systems, Friedrich-Schiller-University, and the Georgia Institute of Technology has found that contrary to prior research results, dogs do not use their tails to help stabilize their movements. Instead, as they explain in their paper posted on the arXiv preprint, the tails are used as a communications device.

Stem cell model allows researchers to explore the earliest stages of sex determination in mice and humans

During embryonic development, two different cascades of genetic signals determine whether the embryo's primordial gonad will become testes or ovaries, and thus whether the embryo will develop into a male or a female. Disruptions in this process cause disorders in sexual development characterized by a mismatch between sex-determining chromosomes, gonads (ovaries or testicles) and the anatomy of the...

How climate change impacts the Indian Ocean dipole, leading to severe droughts and floods

With a new analysis of long-term climate data, researchers say they now have a much better understanding of how climate change can impact and cause sea water temperatures on one side of the Indian Ocean to be so much warmer or cooler than the temperatures on the other—a phenomenon that can lead to sometimes deadly weather-related events like megadroughts in East Africa and severe flooding in...

New type of entanglement lets scientists 'see' inside nuclei

Nuclear physicists have found a new way to use the Relativistic Heavy Ion Collider (RHIC)—a particle collider at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory—to see the shape and details inside atomic nuclei. The method relies on particles of light that surround gold ions as they speed around the collider and a new type of quantum entanglement that's never been seen...

Hubble finds that ghost light among galaxies stretches far back in time

In giant clusters of hundreds or thousands of galaxies, innumerable stars wander among the galaxies like lost souls, emitting a ghostly haze of light. These stars are not gravitationally tied to any one galaxy in a cluster. The nagging question for astronomers has been: how did the stars get so scattered throughout the cluster in the first place? Several competing theories include the possibility...

High-performance visible-light lasers that fit on a fingertip

Researchers have created visible lasers of very pure colors from near-ultraviolet to near-infrared that fit on a fingertip. The colors of the lasers can be precisely tuned and extremely fast -- up to 267 petahertz per second, which is critical for applications such as quantum optics. The team is the first to demonstrate chip-scale narrow-linewidth and tunable lasers for colors of light below red...

Researchers reveal an added layer of nuance in our sense of smell

The delicate fragrance of jasmine is a delight to the senses. The sweet scent is popular in teas, perfumes and potpourri. But take a whiff of the concentrated essential oil, and the pleasant aroma becomes almost cloying. Indeed, part of the flower's smell comes from the compound skatole, a prominent component of fecal odor.

Here today, gone tomorrow: How humans lost their body hair

Orangutans, mice, and horses are covered with it, but humans aren't. Why we have significantly less body hair than most other mammals has long remained a mystery. But a first-of-its-kind comparison of genetic codes from 62 animals is beginning to tell the story of how people -- and other mammals -- lost their locks.

Microwave imaging of quasi-periodic pulsations at flare current sheet

Quasi-periodic pulsations (QPPs; also known as quasi-periodic oscillations, i.e., QPOs) are electromagnetic emission phenomena that vary quasi-periodically with time. They appear in celestial transient events with different temporal/spatial scales, such as stellar flares, gamma ray bursts and fast radio bursts.

New spectroscopy technique improves trace element detection in liquid

Laser-induced breakdown spectroscopy (LIBS) is a rapid chemical analysis technology that has been well developed for trace element analyses in gases, liquids, and solids. It uses a high-power laser pulse to elicit short-lived, high-temperature plasma in a sample. As the plasma cools, it emits spectral peaks that correspond to elements in the periodic table. Recent exploration has extended LIBS via...

High-performance visible-light lasers that fit on a fingertip

As technologies keep advancing at exponential rates and demand for new devices rises accordingly, miniaturizing systems into chips has become increasingly important. Microelectronics has changed the way we manipulate electricity, enabling sophisticated electronic products that are now an essential part of our daily lives. Similarly, integrated photonics has been revolutionizing the way we control...