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Scientists in China have identified why people with chronic pain often feel more discomfort at night than during the day. The research, led by Zhang Zhi from the University of Science and Technology of China, was published Friday in the journal Science. Although it has long been known that pain follows a daily pattern—usually milder during active hours and stronger during rest—the exact reason was not clear. Scientists were aware that the brain’s internal clock, called the suprachiasmatic nucleus, controls sleep and hormones, but its role in pain was not fully understood. Using advanced techniques, researchers traced a specific nerve pathway in mice linking this brain clock to the spinal cord. They found that this pathway is influenced by the body’s natural daily rhythm. Since mice are active at night and rest during the day, the pattern is opposite to humans. During their resting period, the brain clock is more active, which increases pain signals. When the mice are active, the brain activity drops, reducing the intensity of pain. The findings help explain why pain sensitivity changes over the course of a day. Researchers say this discovery could help improve pain treatment by timing medications according to the body’s natural biological clock.

Scientists have warned that a newly identified tree species in Australia, nicknamed the “zombie tree,” could disappear within a generation if urgent action is not taken. Researchers say the tree, Rhodamnia zombi, is still alive in some places but cannot grow or reproduce normally because of a fungal disease known as myrtle rust. Professor Rod Fensham, a botanist at the University of Queensland, said the species was first assessed in 2020 before it even had an official name. Since then, about 10 percent of the trees have died, and the remaining ones are unable to produce flowers or fruit due to the disease. Rhodamnia zombi is a small to medium-sized rainforest tree with large dark green leaves, shaggy bark and fuzzy white flowers. It grows in the Burnett region of Queensland. According to researchers, the bright yellow fungal pathogen repeatedly attacks and destroys the tree’s young shoots. As a result, infected trees cannot grow or reproduce properly and eventually die. Myrtle rust was first detected in Australia in 2010 and has since threatened many plant species. Because of this risk, Rhodamnia zombi has been placed on a special list of plants considered potentially critically endangered.Fensham said the 17 species on this “Category X” list could disappear within a generation without intervention, as none appear to have resistance to the disease. However, scientists remain hopeful. Fensham said related species in the Rhodamnia group have shown some resistance to myrtle rust, raising hopes that future generations may survive. Researchers are collecting healthy cuttings from the wild and growing seedlings at protected sites in Lismore and Townsville. If some trees develop resistance, they may eventually be replanted in forests to restore the species. The findings were published in the journal ‘Austral Ecology’. Source: Science daily

Scientists have found possible evidence suggesting that some killer whales may hunt and eat their own species in waters near Russia. The discovery comes after two severed fins of killer whales were found on a remote Russian island. According to a recent study, both fins carried clear tooth marks from other killer whales, raising concerns that some orcas may be attacking members of their own species. Dr. Olga Filatova, an associate professor at the University of Southern Denmark, said she first saw photographs of the fins sent by her long-time collaborator Sergey Fomin. She said the discovery was unexpected. “When he found the first one, it was very surprising,” Filatova told BBC Science Focus, adding that scientists never expected to witness such behaviour in their lifetime. Genetic tests showed the fins belonged to resident killer whales, a population that mainly eats fish and lives in close family groups spanning several generations. Researchers believe the likely attackers were transient killer whales, another group that lives in the same waters but hunts marine mammals such as seals, sea lions and even other whales. Scientifically, the incident could be considered cannibalism because all killer whales belong to a single species, ‘Orcinus orca’. However, Filatova noted that resident and transient killer whales rarely mix, do not interbreed and may not even recognise each other as the same type of animal. Researchers believe the attacks may have occurred during large gatherings when many resident whale families meet for breeding. During these events, young whales can become separated from their family groups, making them easier targets for mammal-hunting orcas. Both fins belonged to young whales. Scientists also noted that predators often remove fins when hunting to reach the flesh underneath. While the findings are based on only two fins, researchers say the evidence could help explain why resident killer whales maintain such strong family bonds, possibly as protection against predators from other killer whale groups.

Scientists say the Moon, Earth’s closest neighbour, is shrinking faster than previously thought, a discovery that could affect future lunar exploration. Research by the National Air and Space Museum’s Center for Earth and Planetary Studies shows that as the Moon’s interior cools, its surface contracts, creating tectonic features such as lobate scarps and small mare ridges (SMRs). The SMRs, which are relatively young and widespread, suggest that the Moon is still geologically active. These features may also indicate new sources of moonquakes, which could influence where astronauts and equipment are placed on future missions. “This work gives us a complete view of recent lunar tectonism, helping understand its interior, thermal history, and potential for moonquakes,” said Cole Nypaver, lead author of the study. The shrinking Moon poses real risks for human exploration. NASA warns that moonquakes caused by surface contraction can originate 20–30 km deep, reach up to magnitude 5.5, and last more than 10 minutes. Such seismic activity will need to be considered when selecting landing sites and designing infrastructure for programs like Artemis, which aims to return humans to the Moon by 2028. Tom Watters, senior scientist emeritus, said the discovery of young ridges in the lunar maria completes a global picture of a dynamic, contracting Moon. Understanding these tectonic changes is critical for the safety of astronauts and the success of future scientific missions. Scientists continue to study the Moon’s internal dynamics to better understand its history and evolution, while providing crucial data for the next wave of lunar exploration. With inputs from BBC.

Horses often whinny to greet companions, call new friends or show excitement during feeding time. Scientists have long wondered how they create this special sound, known as a neigh. A new study has now revealed the secret. Researchers found that a horse’s whinny is actually a mix of both low- and high-pitched sounds produced at the same time. The low tone is created when air passes over vibrating tissues in the voice box, similar to how humans speak or sing. The high-pitched tone, however, had puzzled experts for years. Larger animals usually make deeper sounds because of their bigger vocal systems. But horses appear to break that rule. According to the study published in the journal Current Biology, horses produce the higher pitch by whistling. Scientists used a tiny camera inserted through the animals’ noses to observe the voice box while they whinnied and made softer “nickering” sounds. They also scanned the vocal structures and tested airflow through voice boxes from deceased horses. They discovered that as air vibrates the tissues in the voice box, an area just above tightens and leaves a small gap, allowing a whistle-like sound to escape. Unlike humans, who whistle with their mouths, horses whistle internally through their voice box. Jenifer Nadeau of the University of Connecticut, who was not part of the study, said the finding was surprising and helps explain the unique tone of a neigh. Researchers also noted that while small rodents can whistle this way, horses are the first known large mammals to do so. Alisa Herbst from Rutgers University said the two-tone call shows that a whinny is more complex than previously thought. Study author Elodie Mandel-Briefer of the University of Copenhagen added that the dual tones may help horses express different emotions at once when interacting socially. Scientists are still exploring how this rare vocal ability evolved, as closely related animals like donkeys and zebras cannot produce the same high-pitched sound.

Meteorologists say the natural El Nino cycle, which shapes global weather, is both influencing and being influenced by a warming planet. A new study suggests an unusual recent shift in the El Nino–La Nina cycle may help explain why Earth’s already rising temperature jumped sharply over the past three years. At the same time, scientists have revised how El Niño and La Niña are defined because rapid climate change is altering ocean conditions. Persistently hotter global waters led the U.S. National Oceanic and Atmospheric Administration (NOAA) this month to change how it determines when the cycle shifts, likely resulting in more events labeled La Niña and fewer classified as El Niño despite warming tropical seas. Brain organoids show goal-directed learning in control task Earth’s average monthly temperature rose markedly above the long-term human-caused warming trend in early 2023 and continued through 2025. Possible causes include faster greenhouse gas warming, reduced ship pollution, an underwater volcanic eruption and increased solar output. A Nature Geoscience study by Japanese researchers found Earth’s “energy imbalance” — the gap between incoming and outgoing energy — increased in 2022, trapping more heat and raising temperatures. About three-quarters of this change was linked to long-term climate change combined with a shift from a three-year cooling La Niña to a warm El Niño phase. El Niño is the natural warming of parts of the equatorial Pacific that alters global weather, while La Niña features cooler waters. El Niño generally boosts global temperatures, while La Niña suppresses the long-term rise and can worsen U.S. hurricanes and drought. From 2020 to 2023, Earth experienced an unusual “triple dip” La Niña, trapping extra heat. About 23% of the recent energy imbalance came from this prolonged event, while slightly over half came from fossil-fuel greenhouse gases. Rare smiling fossil found on Holy Island Because “normal” temperatures keep shifting, NOAA replaced its old 30-year baseline with a relative index comparing Pacific temperatures to the rest of the tropics, improving atmosphere–ocean interaction tracking. NOAA forecasts another El Niño later this year, which could curb Atlantic hurricanes but push global temperatures higher in 2027 and possibly set a new record.

Researchers say two artifacts discovered along a lakeshore in Greece are the oldest known wooden tools yet uncovered, dating back about 430,000 years. One artifact is a slender stick measuring roughly 2½ feet (80 centimeters) in length that may have been used to dig into muddy ground. The second is a smaller, more enigmatic handheld piece made from willow or poplar wood that researchers believe could have been used in shaping stone tools. The findings were published Monday in the journal Proceedings of the National Academy of Sciences. Scientists believe early humans relied on a wide range of tools crafted from stone, bone and wood. However, evidence of wooden tools is rare because the material decomposes rapidly over time. Preservation typically occurs only in specific conditions, such as icy environments, caves or underwater settings. The newly discovered wooden tools were found in Greece’s Megalopolis basin, where researchers believe they were rapidly buried by sediment and preserved over time by wet conditions. Scientists have previously uncovered other remains at the site, including stone tools and elephant bones bearing cut marks. Although the wooden tools were not directly dated, the site itself is estimated to be about 430,000 years old, offering clues to their age. Read More: Science and local sleuthing uncover 250-year-old Shipwreck on Scottish Island “I’ve always just been thrilled to be able to touch these objects,” said study author Annemieke Milks of the University of Reading. No human remains have yet been identified at the location, leaving uncertainty over who used the tools. Possible users include Neanderthals, early human ancestors or other hominins. Archaeologist Jarod Hutson of the Smithsonian National Museum of Natural History said the site may contain additional discoveries, though the plain appearance of the tools makes interpretation difficult. The find adds to rare examples of ancient wooden tools and sheds light on a lesser-known aspect of early human technology.

Scientists have identified a new species of dinosaur in Argentina after unearthing remarkably complete fossils, including remains showing it may have feasted on an ancient crocodile relative. The predator, named Joaquinraptor casali, measured around 23 feet (7 meters) in length and belonged to a little-understood group of dinosaurs known as megaraptorans. These carnivores once roamed across South America, Australia and parts of Asia, branching into different species over millions of years. Megaraptorans are noted for their elongated skulls and “huge and very powerful claws,” said Lucio Ibiricu of the Patagonian Institute of Geology and Paleontology, who led the discovery. But their hunting behavior and place in the evolutionary chain remain unclear because of previously incomplete fossil records. The newly discovered fossils — including parts of a skull, arms, legs and tail — were found in the Lago Colhué Huapi rock formation of Patagonia. Distinctive features in the remains confirmed to researchers that they had uncovered a new species. “This fills a major gap by providing one of the most complete skeletons yet,” said Federico Agnolin of the Argentine Museum of Natural Science Bernardino Rivadavia, who was not involved in the study. The findings were published Tuesday in the journal Nature Communications. Scientists estimate the dinosaur lived between 66 and 70 million years ago, close to the end of the Cretaceous period, and was at least 19 years old when it died. A front leg bone from an ancient crocodile relative, found pressed against its jaws, may provide insights into its diet and role as a possible top predator in the region’s lush prehistoric floodplains. Ibiricu named the new species after his young son, Joaquin. “All children love dinosaurs, so he would probably be a fan too,” he said.  

Embracing the concept of imaginary numbers can be challenging, as they represent a number that doesn't exactly exist in the traditional sense. However, if one opens their mind to this concept, a new realm of possibilities becomes accessible. Wind-driven brush fire on New York's Long Island 50 percent contained. Firefighter injured As a mathematician specialising in analysis—a field of mathematics that involves complex numbers— I deal with numbers that consist of both real and imaginary components. Unlike familiar real numbers, which include integers, fractions, square roots, and even pi, complex numbers incorporate the imaginary number i, which is defined as the square root of -1. To understand this, remember that a square root of a number refers to a number that, when multiplied by itself, equals the original number. While a positive number squared results in a positive number, a negative number squared results in a positive number as well. The imaginary number i represents a number that, when squared, results in a negative number. Non-mathematicians often question the validity of imaginary numbers, asking, “But do these numbers really exist?” Even great mathematicians struggled with complex numbers. For instance, Girolamo Cardano, in his 1545 work Ars Magna, dismissed them as “subtle as they are useless.” Likewise, Leonhard Euler, one of the most renowned mathematicians, once made an error by calculating the square root of a negative number incorrectly. In high school, you may have encountered the quadratic formula, which solves equations involving squared unknown variables. Teachers may have avoided addressing situations where the expression under the square root (b² - 4ac) is negative, suggesting this issue would be tackled later in college. However, if you accept the existence of square roots of negative numbers, you unlock the potential to solve a whole new category of quadratic equations, leading to the fascinating and practical world of complex analysis. The benefits of complex numbers in mathematics What does embracing complex numbers offer? For one, trigonometry becomes much easier. Instead of memorising several complex trigonometric formulas, Euler’s formula provides a single equation that simplifies many of these formulas, making them easier to handle. Calculus, too, becomes simpler. As noted by mathematicians like Roger Cotes and René Descartes—who coined the term "imaginary number"—complex numbers allow for the straightforward calculation of integrals and the measurement of areas under complex curves. Complex numbers also assist in understanding geometric shapes that can be constructed with just a ruler and compass. Mathematicians such as Jean-Robert Argand and Carl Friedrich Gauss used complex numbers to manipulate geometric figures like pentagons and octagons. Applications of complex analysis in the real world Complex analysis has numerous practical applications in the real world. Through the work of mathematician Rafael Bombelli, who explored algebraic operations with complex numbers, these numbers became useful in calculus. This approach has made it easier for scientists to study signals and data transmission. Complex analysis, for example, is essential for working with wavelets—small oscillations in data crucial for removing noise from satellite signals and compressing images for more efficient data storage. Complex analysis is also invaluable to engineers, who use it to simplify complicated problems. It plays a key role in applied physics, such as understanding the electrical and fluid properties of intricate structures. As mathematicians like Karl Weierstrass, Augustin-Louis Cauchy, and Bernhard Riemann gained confidence with complex numbers, they advanced the development of complex analysis, creating a powerful tool that not only simplifies mathematics and propels scientific progress but also makes these subjects more accessible and understandable. Scientists date remains of ancient child that resembles both humans and Neanderthals This article was republished from The Conversation under a Creative Commons license. Read the original article here: https://theconversation.com/taking-a-leap-of-faith-into-imaginary-numbers-opens-new-doors-in-the-real-world-through-complex-analysis-233965.

Expect to see more northern lights in unusual places as the sun continues to sizzle, space weather forecasters said Tuesday. Strong solar storms this year have triggered shimmering auroras much farther south than usual, filling skies with hues of pink, purple, green and blue. The sun is currently at the maximum phase of its 11-year cycle, making solar surges and northern lights more frequent. This active period was expected to last for at least another year, though when solar activity will peak won't be known until months after the fact, according to NASA and the U.S. National Oceanic and Atmospheric Administration. This solar cycle has yielded more colorful auroras farther south and more are likely, said NASA's Kelly Korreck. “We still could possibly get some good shows in the next few months,” she said. Such storms can also temporarily disrupt power and communications. Ahead of a solar outburst, NOAA would alert operators of power plants and spacecraft in orbit. In May, NOAA issued a rare severe geomagnetic storm warning. The storm that slammed Earth was the strongest in more than two decades, producing light displays across the Northern Hemisphere. That same month, scientists recorded the biggest flare erupting from the sun, but Earth was out of the way. Previous solar cycles have produced storms more intense than May's so space forecasters are keeping a close eye on the sun to prepare for any major disruptions, said NOAA’s Bill Murtagh. Sunita Williams to vote in US election from Space Last week, a powerful solar storm dazzled skygazers far from the Arctic Circle when auroras appeared in unexpected places including Germany, the United Kingdom, New England and New York City.