Do you often use your mobile phone to comfort your children? Pay attention; China's perennial rice was selected as one of the top ten breakthroughs of Science in 2022 | Hot Review

"Hotspot Review | Major Technology Events of the Week" is a new column with pictures and texts launched by Academic Headlines, which aims to help readers quickly understand the hot technology news of the past week. Due to the limited space (and knowledge), everyone is welcome to add more~

The consequences of not covering the toilet are serious

Previous studies have found that when flushing the toilet, tiny, invisible particles are released into the air. These particles can transport pathogens such as Escherichia coli, Clostridium difficile, and adenovirus, posing an exposure risk to public toilet users.

Recently, American scientists used green lasers and camera equipment to reveal how tiny droplets of water that are invisible to the naked eye are quickly sprayed into the air when people flush uncovered toilets in public restrooms.

Figure | Aerosol plume generated by flushing the toilet. (Source: Scientific Reports)

The study found that particles from flushing a toilet shoot out at a speed of 2 meters per second and can reach 1.5 meters above the toilet in 8 seconds. While the largest particles tend to settle to the surface of the toilet within a few seconds, aerosol particles smaller than 5 microns, or one millionth of a meter, can remain suspended in the air for several minutes or longer. The plume formed by the spray may rise to the ceiling of the laboratory, and with nowhere else to go, the particles will move outward along the walls and spread to other rooms.

This study is the first to visualize the aerosol plume generated by flushing the toilet and measure its particle splash speed and diffusion trajectory, revealing the impact of flushing the toilet from a new perspective. This visualization of potential disease exposure provides a new way to reduce disease transmission.

Additionally, understanding the trajectory and speed of these particles is important for reducing exposure risks through disinfection ventilation strategies or improved toilet flush design.

Source: China Science Daily

Paper link:

https://www.nature.com/articles/s41598-022-24686-5

China's perennial rice selected as one of Science's top ten breakthroughs of 2022

Recently, Science magazine announced the list of the top ten scientific breakthroughs of the year, among which the development of China's perennial rice varieties was selected.

Photo: Perennial rice can save farmers weeks of hard work every year.

In November 2022, Hu Fengyi's team from Yunnan University in China, in collaboration with relevant teams at home and abroad, published a research paper titled "Sustainable Productivity and Production Potential of Perennial Rice" in the internationally renowned academic journal Nature Sustainability, and simultaneously published a research brief titled "Perennial Rice Transformation Promotes Sustainable Agriculture".

The team's Perennial Rice 23 (PR23) can be harvested without tillage for 3-4 years after planting once . That means from the second season onwards, there is no need for purchasing seeds, raising seedlings, plowing and transplanting, and other production links. Only two production links, field management and harvesting, are required, saving production costs and reducing labor. This is a milestone in the field of perennial food crop cultivation based on interspecific hybridization.

The annual breakthrough list also includes:

The James Webb Space Telescope (JWST) was successfully launched;

Discovery of a giant microbe nearly 5,000 times larger than many bacterial cells;

New insights into how the Black Death altered the genetics of Europeans;

Ancient ecosystems reconstructed from 2-million-year-old environmental DNA preserved in Greenland’s permafrost;

Progress in respiratory syncytial virus vaccines;

NASA successfully implemented the DART satellite mission;

passing a landmark climate bill;

the rapid development of creative artificial intelligence;

Identifying viruses that may cause multiple sclerosis. Source: Science and Technology Daily

Nature releases the "Top Ten Scientists of 2022"

Recently, the top scientific journal Nature announced the list of the top ten people of 2022 (Nature's 10).

This year's list includes some names with a stake in the development of climate change and other global crises . UN Secretary-General António Guterres has called on countries to respond to crises such as climate change; Saleemul Huq, director of the International Center for Climate Change and Development in Dhaka, Bangladesh, helped secure a commitment from wealthy countries to bear the "losses and damages" caused by climate change at last month's international climate talks.

In addition, Nature also selected several people who have made outstanding contributions to global public health issues. As the COVID-19 pandemic enters its third year, Cao Yunlong, a genomics researcher at Peking University, helped track the evolution of the coronavirus and predicted some of the mutations that led to new variants; Lisa McCorkell is a researcher with "long COVID". As a founding member of the Patient-Led Research Collaborative, she helped raise public awareness of the disease and raised research funds; Dimie Ogoina is an infectious disease physician at Niger Delta University in Nigeria. His research on the monkeypox infectious disease in Nigeria provided key information on fighting the monkeypox epidemic.

Muhammad Mohiuddin, a surgeon at the University of Maryland, Baltimore County, led a team to complete the first human transplant of a genetically modified pig heart; Jane Rigby, an astronomer at NASA's Goddard Space Flight Center, played a key role in the mission of the Webb Space Telescope to enter space and operate normally, bringing humanity's ability to explore the universe to a new level.

Original link:

https://www.nature.com/immersive/d41586-022-04185-3/index.html

Why does a high-starch diet aggravate non-alcoholic fatty liver disease?

Non-alcoholic fatty liver disease is a disease of abnormal liver lipid metabolism characterized by massive accumulation of lipids in the liver . The current global prevalence rate is over 25%, and in some parts of China it is as high as 30%. It poses a great threat to people's lives and health and imposes a serious burden on the social economy.

Recently, Wang Zhao's research group at the School of Pharmacy of Tsinghua University systematically demonstrated for the first time the effect of a high-starch diet on non-alcoholic fatty liver disease (NAFLD), and discovered that a high -starch diet mediates the deterioration of NAFLD by mediating high expression of NOX2 and increasing fatty acid transport in a unique metabolic manner.

This study is the first to systematically explore and find at the mouse level that a long-term high-starch diet mediates the occurrence of non-alcoholic fatty liver and further promotes its deterioration. Mechanistically, it clarifies that NOX2, as a specific regulator of this process, mediates the further deterioration of non-alcoholic fatty liver by increasing fatty acid transport, revealing the unique metabolic characteristics of starch carbohydrates that are different from free sugars.

In addition, this study systematically explains the impact of starch, an important nutrient, on the body's physiology and pathology and its metabolic mechanism, providing new ideas for precise nutritional measures to improve non-alcoholic fatty liver disease, and providing scientific dietary nutrition guidance and reference for NAFLD patients.

Source: Tsinghua University

Paper link:

https://www.sciencedirect.com/science/article/pii/S2213453022002452

Do you often use your mobile phone to comfort your children? Learn about these side effects

Using electronic devices to soothe children may seem like a harmless, temporary tool to relieve stress in the family, but if it becomes a regular soothing strategy, it can have long-term consequences for children.

Recently, a study published in the Journal of the American Medical Association-Pediatrics found that frequently using electronic devices such as smartphones and tablets to soothe children aged 3-5 years old will increase children's emotional disorders, especially boys.

The association between device calmness and emotional consequences was particularly high for children, especially boys, who may experience hyperactivity, impulsivity and temper tantrums, making them more likely to react strongly to emotions such as anger, frustration and sadness.

"Especially in early childhood, these devices may hinder children's independence and self-regulation ," said lead author Jenny Radesky, a developmental-behavioral pediatrician at the University of Michigan Mott Children's Hospital.

She pointed out that the preschool to kindergarten period is a special developmental stage, and children may be more likely to exhibit difficult behaviors, such as temper tantrums, defiance and strong emotions. This may lead many parents to choose electronic devices as a parenting strategy. However, the more frequent the use of electronic devices, the less opportunities children and their parents have to use other coping strategies.

There are many other soothing methods that can help build emotion regulation skills, Radesky suggests. Sensory skills, which include rocking, cuddling, jumping on a trampoline, and listening to music or reading a book, are examples. If you see your child fidgeting, you can channel that energy into physical movement.

Source: China Science Daily

Paper link:

https://jamanetwork.com/journals/jamapediatrics/article-abstract/2799042

Scientists reveal the mechanism behind the surge in atmospheric methane concentration in 2020

Methane is an important greenhouse gas. In the past 15 years, the concentration of atmospheric methane has shown an accelerating growth trend, and in 2020 it even reached the maximum value recorded by station observations since 1984. If the concentration of atmospheric methane continues to accelerate in the future, it will bring severe challenges to emission reduction and the realization of the temperature control goals of the Paris Agreement.

The team of researcher Peng Shushi from the School of Urban and Environmental Studies at Peking University collaborated with a number of domestic and foreign research institutions to explore the reasons for the surge in atmospheric methane concentrations in 2020 based on multi-source data such as atmospheric methane concentration observations, energy and agricultural inventory data, meteorology and remote sensing, using wetland process models, atmospheric chemical transport models and atmospheric inversion models, combined with greenhouse gas source and sink assessment methods.

The study found that half of the accelerated growth of atmospheric methane concentration in 2020 was attributed to increased natural emissions led by wetlands, and the other half was attributed to a decrease in the concentration of tropospheric OH radicals. This study provides new insights into understanding the global methane budget, reveals that wetland methane emissions cannot be ignored in achieving global temperature control goals, and recognizes that future methane reduction plans need to simultaneously consider changes in the lifetime of atmospheric methane caused by changes in the emission trends of anthropogenic pollutants such as nitrogen oxides, providing a scientific basis for achieving the goals of the Paris Agreement and global methane reduction commitments.

Source: Peking University

Paper link:

https://www.nature.com/articles/s41586-022-05447-w

Scientists invent new fabric for thermal management of the human body

Maintaining a comfortable metabolic temperature is essential to maintaining basic physiological functions of the human body. Outdoors, a stationary adult consumes about 50% of heat through infrared radiation, and traditional textile materials (such as cotton and polyester) have high infrared emissivity (~90%), resulting in a large amount of radiative heat loss. Therefore, processing the fabric surface to achieve human thermal management will make up for these shortcomings.

At present, the reported thermal management fabric absorption rate is not ideal and cannot effectively heat the human body in cold weather, and the existing selective absorption coating technology will lose spectral selectivity on the surface of ordinary cotton cloth due to high roughness. Therefore, it is of great significance to study zero-energy thermal management fabrics.

Recently, Gao Xianghu, Liu Gang and other researchers from the Clean Energy Chemistry and Materials Laboratory of the Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, prepared a multilayer film based on high entropy nitride (ZrNbMo-Al-N) on the surface of ordinary cotton cloth through magnetron sputtering, realizing a human body thermal management fabric with high spectral selectivity.

By establishing a steady-state heat transfer model, the researchers found that the high absorptivity and low emissivity of fabrics contribute to the insulation of the human body in low-temperature environments. In particular, the optimization of the absorptivity can effectively increase the insulation capacity in outdoor lighting environments.

Based on this, the researchers optimized the optical properties of the multilayer film by combining theoretical calculations with experimental verification. The optimized selective absorption coating achieved a high absorption rate of 92.8% and a low emissivity of 39.2% on cotton cloth modified with metal aluminum, with excellent light-to-heat conversion efficiency, which has obvious advantages over the reported solar heating fabrics. The researchers experimentally verified the heating capacity of the fabric. Due to the lower emissivity of the fabric, the set temperature of the indoor air conditioner was reduced by 3.5°C, thereby reducing energy consumption.

Source: Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences

Paper link:

https://onlinelibrary.wiley.com/doi/10.1002/advs.202204817

Scientists make new progress in video adversarial attacks

Deep neural networks are vulnerable to adversarial attacks, which can cause misclassification by superimposing very small perturbations on images or videos. Researching adversarial attacks on video classification systems will help discover the vulnerability of classification models and become an important basis for improving model robustness.

The current adversarial attack methods in academia all consider norm-restricted perturbations, which requires a large number of queries and results in huge computational costs during the attack. The generated adversarial samples can also be effectively defended by methods such as denoising or adversarial training. There is little research on methods to improve query efficiency and defense capabilities.

To this end, the team led by Associate Professor Xiao Xi of Tsinghua University Shenzhen International Graduate School proposed a black-box video adversarial attack method (StyleFool) based on style transfer to attack the video classification system. This method uses semantically unchanged unrestricted perturbations, aiming to not change the semantic information of the video and not impose norm restrictions on the adversarial perturbations.

Figure｜StyleFool attack diagram

Compared with similar methods, StyleFool can significantly improve the success rate of attacks and reduce the number of queries. At the same time, in terms of the performance of resisting video adversarial defense methods, since StyleFool considers the consistency constraints between previous and next frames and the semantically unchanged unlimited perturbations, the adversarial samples it generates can easily bypass advanced video defense methods.

StyleFool generates unlimited perturbations without changing semantic information, breaking away from the constraints of traditional norm-restricted attacks. It is superior to existing adversarial attack methods in terms of attack performance and defense performance, greatly reducing the cost of attack. It is a major breakthrough in the direction of non-semantic adversarial attacks.

Source: Tsinghua University Shenzhen International Graduate School

Paper link:

https://arxiv.org/abs/2203.16000

American football players may suffer from multiple chronic "occupational diseases"

Recently, a team from the Harvard T.H. Chan School of Public Health, Harvard Medical School and their collaborators discovered that compared with the general population with similar demographic characteristics, American football players tend to develop age-related diseases such as hypertension and diabetes earlier, and in severe cases, their healthy life expectancy may be shortened by nearly ten years.

The study is based on a follow-up survey of nearly 3,000 retired American football players, which is the largest data sample of former professional American football players to date. The research team said that the physical condition of retired football players has important guiding significance for the relationship between football and health.

However, this finding does not determine the cause of the premature onset of chronic diseases in American football players, but it reveals the correlation between these players and the onset of chronic diseases , which has potential value for future research on cell- and organ-specific pathophysiology.

Paper link:

https://bjsm.bmj.com/content/early/2022/12/12/bjsports-2022-106021