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July 31 (Wednesday) news, well-known foreignscienceThe main contents of the website are as follows:

Nature website (www.nature.com)

Artificial intelligence makes plagiarism more complicated. How should scientists and publishers respond?

The academic world has long been plagued by plagiarism. However, a bigger problem is emerging in academic writing: Generative AI tools based on large language models (LLMs), such as ChatGPT, are rapidly gaining popularity, sparking a discussion on whether plagiarism constitutes plagiarism and under what circumstances it should be allowed.

These tools can save time, improve the clarity of texts, and alleviate language barriers. Currently, many researchers believe that their appropriate use in certain circumstances is acceptable, but only if it is fully disclosed.

However, these tools have heightened the controversy over the inappropriate use of others’ work. LLMs generate texts by analyzing large numbers of published articles, so their use could give rise to plagiarism-like behaviour, for example if researchers use machine-generated text without declaring it, or if machine-generated text closely resembles a work without attributing its source. These tools could also be used to mask intentional plagiarism, and their use could be difficult to detect.

Currently, many journals have established policies that allow the use of LLM to a certain extent. An analysis of 100 large academic publishers and 100 highly ranked journals showed that as of October 2023, 24% of publishers and 87% of journals have guidelines on the use of generative AI. Almost all institutions that provide guidelines stipulate that AI tools cannot be listed as authors, but there are differences in the types of AI that are allowed and disclosure requirements. Experts believe that there is an urgent need to develop clearer guidelines to regulate the use of AI in academic writing.

Science website (www.science.org)

humidityWill it make the heat more deadly? Scientists disagree

Last summer, the Northern Hemisphere experienced record-breaking heat. A paper in Environmental Health Perspectives (EHP) found a significant disagreement among researchers about whether humidity made hot weather more deadly.

Physiologists have found strong evidence to support the importance of humidity: at a given temperature, increased humidity makes it harder for the body to maintain a safe core temperature, increasing the risk of heat stroke. In contrast, studies by epidemiologists have shown that temperature alone is an accurate predictor of heat-related mortality, while adding humidity as a predictor seems less helpful.

Addressing this question is important. Rising global temperatures put more people at risk of heat-related deaths, especially in the world's hottest regions, such as South Asia, Southeast Asia and the Persian Gulf, which also experience extreme hot and humid conditions. So scientists' understanding of the role of humidity could affect everything from the thresholds for government heat warnings to recommended cooling methods.

Humid heat is more unbearable than dry heat, and is considered more deadly for good reason: once the air temperature exceeds 35 degrees Celsius, the body cools down only through the evaporation of sweat. The higher the humidity in the air, the less sweat evaporates, making it less effective as a cooling mechanism.

A possible reason epidemiologists haven’t observed humidity’s effects is that their datasets are skewed primarily toward the cooler, drier global North, which can make it difficult for them to see the actual deadly impacts of humidity in the global South, especially since accurate mortality data are difficult to obtain in these regions.

Science Daily website (www.sciencedaily.com)

1. NASA data shows that July 22, 2024 isEarthHottest day on record

July 22, 2024, became the hottest day on record, according to NASA's analysis of daily global temperature data. The temperature on that day surpassed the previous record set in July 2023. These record-breaking temperatures are part of a long-term warming trend in the climate caused by human activities, primarily greenhouse gas emissions. As part of expanding our understanding of how the Earth is changing, NASA continues to collect critical long-term climate change data.

The preliminary findings come from analysis of data from the Modern Era Retrospective Research and Applications Analysis, version 2 (MERRA-2) and Goddard Earth Observing System Forward Processing (GEOS FP) systems, which integrate global observations collected by millions of instruments on land, at sea, in the air and on satellites.

The GEOS FP system provides rapid, near real-time weather data, while the MERRA-2 climate reanalysis takes longer to ensure that the best possible observations are used for the analysis.

NASA's analysis is consistent with an independent analysis by the European Union's Copernicus Earth Observation Program, and although there are minor differences, they show broad agreement on how temperatures change over time and on the record of the hottest day on record.

2. Severe influenza in mothers can affect the fetus' brain: new mouse studies explain

Severe influenza infection during pregnancy increases the risk of fetal neurodevelopmental disorders, such as schizophrenia and autism spectrum disorder. But it is not the virus itself that causes these impairments, but the mother's immune response.

New research from the University of Illinois at Urbana-Champaign (UIUC) uses mice adapted to live influenza viruses to explain this process at the cellular and molecular levels, building on previous experiments that showed that changes in the fetal brain are more likely only when the mother's infection reaches a certain severity.

The study is one of the few of its kind to use doses of live influenza virus to replicate seasonal influenza outbreaks in humans. "This means our findings are more relevant to pathological infections in humans," said the study's lead author.

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

1. Ancient fossil discovery shows how South America and Africa separated

Ancient rocks and fossils of long-extinct marine reptiles discovered in Angola provide clear evidence for the separation of South America and Africa and the formation of the South Atlantic Ocean, an event that was a critical moment in Earth history, according to a Southern Methodist University (SMU)-led research team.

It has long been known that the west coast of Africa and the east coast of South America were once closely connected in the supercontinent Gondwana, similar to two pieces of a jigsaw puzzle.

The team says their excavations off the southern coast of Angola provide arguably the most complete geological record ever recorded of the landmass that separated the two continents and opened up the South Atlantic Ocean. They found rocks and fossils dating from 130 million to 71 million years ago.

The team's field work began in 2005 in Namibe Province, Angola, when the team identified specific types of sediments that indicate what the landforms of Africa's west coast looked like millions of years ago. For example, lava fields reveal evidence of volcanic activity, faults or cracks show where continents were torn apart, sediments and salt layers show flooding and evaporation of the ocean, and overlying marine sediments and fossils of marine reptiles show the full formation of the South Atlantic Ocean.

Meanwhile, paleontologists in Angola have discovered fossils of large marine reptiles that lived during the Late Cretaceous, when the Atlantic Ocean was just forming and widening.

2. ScientistsMilky WayIn addition, a rare second generationstar

The universe was forever changed by the first generation of stars. In their cores, basic hydrogen and helium fused into a wide variety of elements. When these stars ended, they exploded, and these new elements were scattered across the universe. The iron in our blood vessels, the calcium in our teeth, and the sodium in our brains all originated from the heart of a long-dead star.

No one has been able to find a first-generation star, but scientists have announced a unique discovery: the discovery of a second-generation star that formed in a galaxy outside our own Milky Way.

Anirudh Chiti, a postdoctoral fellow at the University of Chicago and the paper's lead author, specializes in so-called stellar archaeology: reconstructing how the earliest generations of stars changed the universe.

But no one has yet been able to directly observe these first-generation stars, if any still exist in the universe. Instead, Chitty and his colleagues search for stars that formed from the ashes of the first stars.

This is hard work, because even second-generation stars are now very old and rare. Most stars in the universe, including our own sun, evolved over thousands to tens of thousands of generations, producing more and more heavy elements each time. Perhaps less than 1 in 100,000 stars in the Milky Way is this second-generation star, which is really a needle in a haystack job.

For this study, Kitty and his colleagues pointed their telescopes at an unusual target: the stars that make up the Large Magellanic Cloud.

The Large Magellanic Cloud is a bright band of stars visible to the naked eye from the Southern Hemisphere. We now think it was once a separate galaxy that was captured by the Milky Way's gravity billions of years ago. This makes it particularly interesting because its oldest stars formed outside the Milky Way, giving astronomers a chance to learn whether conditions in the early universe were the same, or different elsewhere.

Scientists looked for evidence of these particularly old stars in the Large Magellanic Cloud and catalogued 10 of them. One of the stars looked strange. It had much fewer heavy elements than any other star in the Large Magellanic Cloud. This means it probably formed after the first generation of stars formed, so it has not yet accumulated heavier elements in the repeated birth and death of stars. (Liu Chun)