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On July 23 (Tuesday), the main contents of the well-known foreign scientific website are as follows:

Science News website (www.sciencenews.org)

Scientific simulation found:planetTo beEarthSimilarly, you need to have the right amount of water at the beginning

The process of planet formation is like playing poker, you have to play the cards you are dealt. If the goal is to become an Earth-like planet, it is best to start with 3 to 8 times the amount of water in Earth's oceans.

Astronomers believe that thestarOrbiting rocky planets is probably the most common habitat for life in the Milky Way. But these stars have bad tempers and can strip a planet of its water with high-energy flares within a few billion years of its birth.

Keavin Moore, a planetary scientist at McGill University in Canada, and his colleagues wondered what would happen if planets could hide water destined to become oceans and atmospheres in their interiors until their host stars calmed down as they aged. The team ran a simple simulation of a planet's life cycle, in which a planet is born hot and molten, with some water dissolved in a magma ocean throughout the planet. It could start out with a lot of water of its own, or it could be brought more water later by comets or asteroids.

As the planet cools, the water evaporates and forms an atmosphere. Some of the water is swallowed up by space, but some enters a cycle where it dissolves in the planet's mantle and escapes back into the atmosphere. Storing the water in the mantle protects it from being destroyed by the intense light of the host star.

Moore and his colleagues found that in this simulation, for an Earth-mass planet to eventually form oceans and continents after about 5 billion years, it would need to have three to eight times as much water as Earth's oceans when it formed. A planet that started out with 12 times as much water as Earth's oceans could end up as a water world, with the planet's surface completely covered by ocean. Such a planet could actually exist and could theoretically support life even without land.

Science Daily website (www.sciencedaily.com)

1. Metallic minerals on the deep seafloor can produce oxygen, challenging long-standing assumptions

An international research team has discovered that metallic minerals on the deep seafloor, 13,000 feet below the surface, can produce oxygen.

The surprising discovery challenges the long-held assumption that only photosynthetic organisms such as plants and algae can produce oxygen on Earth. But the new findings suggest there may be another way. Oxygen also appears to be produced on the seafloor, where no light can penetrate, to support oxygen-breathing marine life living in total darkness.

The research was recently published in the journal Nature Geoscience.

Andrew Sweetman, a seafloor ecology expert at the Scottish Association for Marine Science (SAMS), discovered the dark oxygen while on a shipboard field trip in the Pacific Ocean. An electrochemical experiment led by Franz Geiger, a chemistry professor at Northwestern University, may explain the phenomenon.

"For aerobic life to start on Earth, you have to have oxygen, and our understanding is that Earth's oxygen supply started with photosynthetic organisms," Sweetman said. "But we now know that oxygen is produced in the deep ocean, where there is no light. So I think we need to re-examine the question: Where did aerobic life start?"

Polymetallic nodules are natural mineral deposits that form on the seafloor and are at the heart of the discovery. They are a mixture of various minerals ranging in size from a tiny grain to a common potato.

"The polymetallic nodules that produce this oxygen contain metals such as cobalt, nickel, copper, lithium and manganese, which are key elements used in batteries," said Geiger, a co-author of the study. "Several large mining companies are now aiming to extract these precious elements from the seafloor 10,000 to 20,000 feet below the surface. We need to rethink how we mine these materials so we don't deplete the source of oxygen for deep-sea life."

2. Scientists have found a way to efficiently convert carbon dioxide into methanol

For years, chemists have struggled to synthesize high-value materials from discarded molecules. Now, an international collaboration of scientists is exploring ways to use electricity to streamline the process.

In their recent study published in the journal Nature Catalysis, the researchers demonstrated that carbon dioxide, a greenhouse gas, can be efficiently converted into a liquid fuel called methanol.

The process is achieved by evenly spreading cobalt phthalocyanine (CoPc) molecules on carbon nanotubes, a graphene-like tubular structure with unique electrical properties. Their surface is an electrolyte solution, and by passing electricity through it, the CoPc molecules can gain electrons and use them to convert carbon dioxide into methanol.

Using a special method based on in situ spectroscopy to visualize chemical reactions, the researchers saw for the first time that these molecules convert themselves into methanol or carbon monoxide, which are not the desired products. They found that the path of the reaction is determined by the environment in which the carbon dioxide molecules react.

Tuning this environment by controlling how the CoPc catalyst is distributed on the surface of the carbon nanotubes can make the production of methanol from carbon dioxide eight times more likely, a finding that could improve the efficiency of other catalytic processes and have broad implications in other fields.

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

1. Scientists have discovered that the brain can be asleep and awake at the same time

Scientists have developed a new method to analyze sleep and wakefulness by detecting ultrafast patterns of neuronal activity that last only milliseconds, challenging the traditional understanding of sleep based on slower brain waves. The study also found that individual brain regions can briefly and independently switch between sleep and wakefulness, revealing complex local brain activity that may reshape our understanding of the mechanisms of sleep.

Sleep and wakefulness are completely different states of existence that define the boundaries of our daily lives. For years, scientists have measured the differences between these instinctive brain processes by observing brain waves, with sleep being characterized by slow, prolonged brain waves that travel throughout the organ at a rate of one-tenth of a second.

Scientists have discovered for the first time that sleep can be detected by patterns of neuronal activity that are only a few milliseconds long, revealing a new way to study and understand the basic brain wave patterns that control consciousness. They have also shown that while parts of the brain remain asleep, other small parts of the brain can briefly wake up, and vice versa.

The findings are published in a new study in the journal Nature Neuroscience. Over four years of work, the researchers trained a neural network to detect patterns in large amounts of brain wave data, revealing patterns at extremely high frequencies that had never been described before and challenging long-held fundamental concepts about the neurological basis of sleep and wakefulness.

2. Peking University professor uses facial thermal imaging AI technology to predict disease and biological age

A research team led by Professor Han Jingdong of Peking University found that the temperature of different areas of the face is associated with various chronic diseases, such as diabetes and high blood pressure. These temperature differences are not easily detected by a person's own touch, but can be identified through specific artificial intelligence (AI)-derived spatial temperature patterns, which requires thermal imaging cameras and data training models. The results of the study were recently published in the journal Cell Metabolism. With further research, doctors may one day use this simple and non-invasive method to detect diseases early.

The research team had previously used 3D facial structure to predict people's biological age, which indicates how much the body has aged and is closely related to the risk of diseases such as cancer and diabetes. They were curious whether other features of the face, such as temperature, could also predict aging speed and health.

Jingdong Han and her colleagues analyzed the facial temperatures of more than 2,800 Chinese participants, aged between 21 and 88. The researchers then used this information to train an AI model to predict a person's biological age. They identified several key facial areas where temperature was significantly associated with age and health, including the nose, eyes, and cheeks.

Because of this connection, the research team set out to test whether exercise could affect biological age. They asked 23 participants to jump rope at least 800 times a day for two weeks. To the team's surprise, these participants reduced their biological age by five years after just two weeks of exercise.

Next, the team hopes to explore whether facial thermal imaging can be used to predict other conditions, such as sleep disorders or cardiovascular problems.