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On July 17 (Tuesday), well-known foreignscienceThe main contents of the website are as follows:

Nature website (www.nature.com)

1. Research shows that dogs may have evolved to understand human emotions

A Community Science study comparing the responses of dogs and pet pigs to human cries and grunts suggests that dogs' ability to sense human pain may be innate, a result of centuries of co-evolution with humans. The findings are published in the journal Nature.animalThe study was published in the journal Animal Behaviour.

Humans pay attention to animals' feelings, and that attention appears to be mutual. But few studies have tested whether animals are simply reacting to the odd human voice or are capable of true emotional contagion -- the ability to interpret and reflect a person's emotional state. Most animals can only accurately respond to the feelings of their own kind. But studies have shown that dogs can mirror the emotions of those around them.

One question is whether this emotional contagion is rooted in "universal emotional vocal signals" that all domestic animals understand, or whether it is specific to companion animals such as dogs. To test this, the researchers compared the stress responses of dogs and pet pigs to human voices.

The research team recruited dog or pig owners around the world and had them film themselves and their pets in a room while recordings of crying or groaning were played. The researchers then counted the number of stress behaviors exhibited during the experiment, such as whimpering and yawning in dogs and rapid ear flapping in pigs.

As expected, dogs were "very, very good at picking up the emotional content of our voices." The dogs became stressed when they heard the cries and were largely indifferent to the snorts. However, while the pigs did experience some stress when they heard the cries, their behavior indicated that the snorts were much more stressful.

2. The names of many plants are offensive:botanyThe family will vote on whether to rename

This week, a group that sets rules for naming plant species will vote on whether to rename dozens of organisms whose scientific names contain racial slurs and reconsider other offensive names, such as those that recognize colonialists or advocates for slavery.

The vote at the International Botanical Congress (IBC) in Madrid, Spain, marks the first time taxonomists have formally considered changing the rules to deal with species names that many consider offensive.

Supporters of the proposals argue that as society more broadly addresses questions about reverence for those responsible for historical injustices, so too should science. But some in the taxonomic community worry that collective name changes could sow confusion in the scientific literature and create a "slippery slope" that could threaten any species names named after people.

Every six or seven years, taxonomists meet at a conference called the International Botanical Congress to consider changes to the naming rules for plants, fungi and algae. Later this week, members of the IBO's Nomenclature Section will vote on two proposals involving culturally sensitive names.

Science News website (www.sciencenews.org)

A python-inspired device could make rotator cuff surgery more effective

Two million people in the United States suffer rotator cuff injuries each year, but only 600,000 receive surgery to treat them. A new device inspired by pythons could close that gap.

The failure rate for rotator cuff surgery ranges from 20% to 94%. Doctors sometimes decide not to operate because of the risk of re-tear. But a medical device that mimics a python's fangs could double the strength of surgical repairs and prevent tears when used with standard sutures, researchers report today in Science Advances.

The rotator cuff is a group of muscles and tendons that surround the shoulder, and injuries include tears and inflammation, leading to pain and limited function. Surgical repair is meant to repair the torn tendon, usually by reattaching it to the head of the arm bone. But sutures are only secured at a few points and can re-tear the already fragile tendon.

A team of biomedical engineers at Columbia University in the US has designed a device to solve this problem. The device uses a row of small, sharp teeth that attach to tendons and bones, spreading and relieving pressure on each part of damaged tissue. The device was inspired by nature. Unlike shark teeth, which are sharp, triangular and designed for cutting, python fangs are curved inwards, designed to dig deeper when the animal struggles.

The team first used computation and computer simulations to optimize the size and geometry of the tooth. Using 3D printing, the researchers fabricated the tooth and tooth array before optimizing placement and bite. Working with surgeons, the team tested iterations of the "tooth" on cadavers, securing one shoulder with sutures only and the other with sutures and a device.

The researchers found that the shoulder with the device had twice the support of the shoulder without the device. The researchers said that before entering clinical application, the design needs to be tested in living animals to prove its long-term function and safety.

Science Daily website (www.sciencedaily.com)

1. A study reveals how obesity genes affect the brain

Obesity is a complex condition caused by a combination of genetics, food environment, behavior, and other factors. A gene called SH2B1 has been shown to play an important role in regulating food intake. SH2B1 mutations have been associated with obesity, type 2 diabetes, and fatty liver disease associated with metabolic dysfunction.

A University of Michigan Medical School study pinpoints where this gene works in the brain, a region called the paraventricular hypothalamus (PVH), which is involved in regulating blood pressure and fluid balance.

In addition, the team found that neurons expressing SH2B1 form a circuit that talks to neurons in a region downstream of the dorsal raphe nucleus in the brainstem. This region is involved in energy balance, weight maintenance, and emotion-driven behavior. Stimulating this circuit suppresses the mice's appetite. Conversely, silencing neurons expressing SH2B1 in the PVH leads to obesity.

The team also revealed the molecular mechanism of how SH2B1 helps maintain body weight, in part by enhancing BDNF/TrkB signaling, which promotes brain growth during development and maintains brain health in the mature brain. When this signaling goes awry, obesity and metabolic diseases can emerge.

2. Athletes losing weight before competitions affects both performance and health, with a more serious impact on female athletes

Among athletes, especially in endurance sports such as running, swimming, cycling and rowing, reducing food intake before competition is a common phenomenon.

A new study on the effects of energy deficit in female athletes was recently conducted by the Department of Nutrition, Exercise and Sports Sciences at the University of Copenhagen, Denmark.

For the study, researchers recruited 12 female triathletes who all had normal energy intake. In one part of the trial, the athletes received adequate calories for 14 days, after which their performance was tested. The athletes also underwent a 14-day period where they consumed only about 50% of their energy needs while adhering to their normal high-intensity training schedule.

The study found that during the calorie deficit, the athletes lost an average of about 4% of their body weight, about half of which was muscle mass; their performance also declined: in a 20-minute cycling time trial, their performance dropped by 7.7%. In addition to athletic performance, several aspects of the athletes' immune system were also severely affected, which could make the athletes more susceptible to illness.

Based on the rather limited research in this area, men appear to be able to tolerate reduced energy intake before it has a negative impact, suggesting that women are particularly vulnerable in this regard.

The harmful effects of undereating over a long period of time, especially for women, may also be lifelong, the researchers note.

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

The Silicon Revolution: New Breakthroughs in Laser Nanofabrication

Silicon, the cornerstone of modern electronics, photovoltaics and photonics, has traditionally been limited to surface-level nanofabrication due to challenges with existing lithography techniques. Existing methods are either unable to penetrate the wafer surface without causing alterations, or are limited by the micrometer-scale resolution of laser lithography within silicon.

An innovative technology developed by a research team at Bilkent University in Turkey goes beyond current limitations and can control the movement of electrons buried deep inside silicon wafers with unprecedented control.Nano-structureManufacturing.

The team addressed the dual challenges of complex optical effects within the wafer and the inherent diffraction limit of lasers. They overcame these issues by using a special type of laser pulses generated by a method called spatial light modulation. The non-diffraction properties of the beam overcome the optical scattering effects that previously hindered precise energy deposition, creating extremely small localized voids inside the wafer. This process is followed by an emergent seeding effect, where the pre-fabricated subsurface nanovoids establish strong field enhancements around their neighbors. This new manufacturing regime marks an order of magnitude improvement to the state-of-the-art, achieving feature sizes down to 100 nanometers.

The researchers used spatially modulated laser pulses, technically corresponding to Bessel functions. The non-diffraction properties of this special laser beam, created using advanced holographic projection techniques, allow for precise positioning of the energy. This in turn leads to sufficiently high values ​​of temperature and pressure to alter the material in a small volume. Remarkably, the resulting field enhancement, once established, sustains itself through a seeding-type mechanism. Simply put, the creation of early nanostructures facilitates the fabrication of later ones. The use of laser polarization provides additional control over the alignment and symmetry of the nanostructures, enabling the creation of a variety of nanoarrays with high precision.

The research team demonstrated large-area volume nanostructures with features beyond the diffraction limit, thus achieving proof of concept for buried nanophotonic components. These advances are of great significance for the development of nanoscale systems with unique structures. (Liu Chun)