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On August 16 (Friday), well-known foreignscienceThe main contents of the website are as follows:

Nature website (www.nature.com)

The European JUICE probe will use dualgravitationalFlyover

Next week, the European Space Agency (ESA)'s Jupiter Icy Moons Explorer (JUICE) will fly byMoonandEarth, heading to deep space as part of a daring and unprecedented double gravity flyby.

JUICE's journey will take eight years and will culminate in a visit to Jupiter's three moons. The spacecraft will use the gravity of the Earth, Moon and Venus to reach Jupiter with minimal fuel consumption.

On August 19 and 20, JUICE will fly past the Moon and Earth in rapid succession, performing the first-ever dual gravity-assist maneuvers. JUICE will first reach the Moon, use the Moon's gravity to slow down and change course, and then orbit the Earth a day later to further adjust its speed and direction.

Normally, the Moon's gravity is seen as a distraction when a spacecraft is orbiting Earth, but it can save propellant. The lunar gravity assist technique, combined with the launch time of last April, has allowed JUICE to save enough fuel to orbit Jupiter's moon Ganymede at a distance of 200 kilometers by the end of its mission in 2035.

Double gravity-assist maneuvers are risky because each flyby amplifies any errors in the spacecraft's trajectory. However, conducting such maneuvers close to Earth provides a good opportunity to test whether JUICE's science instruments are working as planned.

JUICE's circuitous route is carefully designed. The Earth-Moon flyby will slow JUICE down and change its course to a shortcut to Venus. JUICE will gain energy while flying around Venus, and two gravity assists from Earth in 2026 and 2029 will finally push the spacecraft toward Jupiter.

Science website (www.science.org)

The celestial body Chicxulub that caused the extinction of the dinosaurs was located inSolar SystemPeripheral formation

[For more details, please read:The culprit of the mass extinction? The latest paper in Science explores the mystery of the origin of giant meteorites 】

The object that struck Earth 66 million years ago and triggered the extinction of the dinosaurs was an object that originally formed outside the orbit of Jupiter, causing the extinction of nearly all non-avian dinosaurs, according to geochemical evidence from the Chicxulub impact site in Mexico.

The findings, published recently in the journal Science, suggest that the mass extinction was triggered by a chain of events at the birth of the solar system, supporting long-held suspicions that the Chicxulub impactor came from an asteroid at the outer edge of the solar system.

The Cretaceous-Paleogene extinction (K-Pg) was one of five mass extinction events that occurred in the past 540 million years, a period when animals were thriving on Earth. The event wiped out more than 60% of species on Earth, including all non-avian dinosaurs.

Since 1980, there has been growing evidence that the K-Pg extinction was triggered by a city-sized body hitting Earth. Such an impact would have thrown a large amount of sulfur, dust, and soot into the air, partially blocking sunlight and causing temperatures to plummet. In the 1990s, scientists found the impact site, a huge underground crater near Chicxulub on the Yucatan Peninsula in Mexico.

To find out the source of the impactor, a research team from the University of Cologne in Germany collected rock samples from three locations in the Chicxulub crater and compared them with samples from eight other meteorite impact craters that occurred over the past 3.5 billion years.

The research team focused on isotopes of ruthenium metal. The researchers said that ruthenium is extremely rare in Earth rocks, so samples collected from the impact site can provide a "pure signature" of the impactor. Ruthenium has seven stable isotopes, and different celestial bodies have their own unique isotope combinations.

In particular, observations of ruthenium isotopes can help researchers distinguish between objects that formed in the extrasolar system (beyond the orbit of Jupiter) and those that originated in the solar system. The study found that the ruthenium isotopes in the Chicxulub impactor closely match carbonaceous asteroids from the outer reaches of the solar system, but not siliceous asteroids from within the solar system.

Ruthenium isotopes also provide support for an alternative hypothesis: that the Chicxulub impactor may have been a comet rather than an asteroid.

Science Daily website (www.sciencedaily.com)

1. Intelligent soft robotic clothing: effectively regulating temperature without consuming energy

As global warming intensifies, people are increasingly exposed to extreme heat. Maintaining a comfortable body temperature is particularly important for those working indoors or outdoors in hot environments. A research team led by Dr. Dahua Shou, a Limin Advanced Textile Technology Young Scholar at the Hong Kong Polytechnic University, has developed an insulated and breathable intelligent soft robotic clothing that can automatically adapt to changing ambient temperatures, helping to ensure the safety of workers in hot environments. Their research results were published in the international interdisciplinary journal Advanced Science.

Thermal protective clothing is essential for protecting individuals in extreme heat environments. However, traditional thermal protective clothing has limitations in static thermal resistance, which may cause overheating and discomfort at normal temperatures, while its thermal insulation performance may be insufficient in extreme fires and other high-temperature environments. To address this problem, Shou Dahua and his team developed intelligent soft robotic clothing that can automatically adjust temperature and thermal insulation performance in hot environments, providing excellent personal protection and comfort within a certain temperature range.

Their research is inspired by biomimicry in nature, such as the adaptive thermal regulation mechanism of pigeons, which is mainly based on structural changes. The protective clothing developed by the team uses soft robotic textiles for dynamic adaptive thermal management. The soft actuator is designed as a human mesh exoskeleton, encapsulating a non-toxic, non-flammable, low-boiling-point liquid, cleverly embedded in the clothing.

This unique soft robotic textile is made of thermoplastic polyurethane, which is soft, elastic and durable. It is worth noting that it is more skin-friendly and comfortable than temperature-responsive clothing embedded with shape memory alloys, and can be used in a variety of protective clothing. This lightweight and soft robotic clothing does not rely on thermoelectric chips or circulating liquid cooling systems for temperature regulation and does not consume any energy.

2. Groundbreaking study identifies genetic variants associated with normal-pressure hydrocephalus

A new study from the University of Eastern Finland and its partners has discovered genetic variants associated with normal pressure hydrocephalus (NPH). The study, published in the journal Neurology, is the world's first large-scale genome-wide association study related to NPH. These results provide new insights into the genetic background of NPH and lay the foundation for further research into the biological mechanisms of NPH.

NPH is a common chronic neurological syndrome in the elderly that affects gait, memory, and bladder control. Currently, the main treatment for NPH is shunt surgery. However, the pathogenesis of NPH is still not fully understood, and its genetic research is relatively limited.

However, idiopathic NPH has been observed to run in families to some extent, and previous studies have identified several individual genetic variants that increase the risk of NPH.

The study found significant variants associated with NPH at six different genetic loci. Some of these genes have been found to be involved in the structure or function of brain regions associated with NPH. These include roles in the blood-cerebrospinal fluid barrier and the blood-brain barrier, as well as an association with increased lateral ventricle size in the general population, a key finding in NPH.

These findings support the hypothesis that NPH is a multifactorial disease.

Scitech Daily website (https://scitechdaily.com)

1. Liquid metal revolutionizes transparent electronic circuit printing

Scientists have developed a breakthrough technique for printing thin films of metal oxides at room temperature, creating transparent, highly conductive circuits that can withstand extreme temperatures.

Researchers at North Carolina State University and Pohang University of Science and Technology in South Korea have demonstrated a technique for printing thin films of metal oxides at room temperature and using the technique to create transparent, highly conductive circuits that are both robust and able to operate at high temperatures.

Metal oxides are important materials that are found in almost every electronic device. Most metal oxides are electrically insulating (like glass), but some are both conductive and transparent, which is crucial for smartphone touchscreens or computer monitors.

In principle, thin films of metal oxides should be easy to make, the researchers say. After all, they form naturally on the surfaces of nearly every metal object in our homes, such as soda cans, stainless steel pots and forks. While these oxides are ubiquitous, their uses are limited because they cannot be stripped from the metal surfaces on which they form.

To achieve this technology, the researchers developed a new method to separate metal oxides from liquid metal menisci. If you fill a tube with liquid, the meniscus is the curved surface of liquid that extends beyond the end of the tube. It is curved because surface tension prevents the liquid from completely overflowing. In the case of liquid metal, the surface of the meniscus is covered with a thin skin of metal oxide that forms where the liquid metal comes into contact with the air.

The researchers demonstrated the technique using several liquid metals and metal alloys, each of which changed the composition of the metal oxide film. They were also able to lay down the film by using the printer multiple times.

Surprisingly, these printed films are not only transparent, but also have metallic properties and extremely high electrical conductivity.

2. A new method can greatly improve the speed and efficiency of COF membrane production

A research team at New York University Abu Dhabi (NYUAD) has developed a new method that uses microwave technology to more easily synthesize and fine-tune a new type of membrane that can effectively purify a variety of pollutants from water. The technique takes only a few minutes to synthesize the membrane, making it one of the fastest ways to make covalent organic framework (COF) membranes. These membranes act as filters in devices designed to clean contaminated water from specific pollutants, allowing them to be reused in different applications - efficient wastewater treatment is critical amid growing global water shortages.

The new dual-sided membrane is characterized by its unique super-hydrophilic and near-hydrophobic surfaces, which can effectively remove pollutants such as oil and dyes from water. This dual functionality not only enhances the filtration process, but also gives the membrane strong antibacterial properties, which is crucial for its long-term use and effectiveness.

The research results were published in the Journal of the American Chemical Society and represent a major breakthrough in the synthesis of high-quality, crystalline, free-standing COF membranes. The researchers said: "Our method not only simplifies the production process, but also improves the separation capacity of the membrane, providing a promising solution to the global water purification challenge." (Liu Chun)