Expanding cognitive boundaries to serve people's lives

——Interpretation of the Top Ten Progresses in Chinese Science in 2020

  ●After 23 days, the Chang'e-5 returner carried lunar samples and landed safely in the planned area of ​​Siziwang Banner, Inner Mongolia.

  ●The Struggle has created a deep dive record of 10,909 meters, which embodies my country's comprehensive strength in the field of marine high-tech, and is an important milestone in my country's deep-sea scientific and technological exploration.

  ●Chinese and Nepalese scientists have carried out scientific and technological cooperation, and for the first time in history, they jointly determined the elevation of the snow surface of Mount Everest based on the global elevation datum of 88.886 meters.

  ●Through cutting-edge experimental methods, we successfully obtained the genomes of 25 individuals from 9500-4200 years ago and 1 individual 300 years ago from 11 sites in the north and south of China, revealing the pattern of north-south differentiation, subject continuity, and migration fusion of the Chinese population since 9,500 history.

  ●Obtained the world's first high-precision Paleozoic evolutionary curve of marine biodiversity for more than 300 million years, and the time resolution is more than 400 times higher than similar international studies.

  On February 27, the High-Tech Research and Development Center (Basic Research Management Center) of the Ministry of Science and Technology released the top ten scientific progress in China in 2020.

Chinese scientists actively responded to the new crown pneumonia epidemic and made outstanding progress and 10 major scientific advances were selected.

  The final selection of the top ten scientific progress in China in 2020 adopts online voting, inviting more than 3,200 experts and scholars, including academicians of the Chinese Academy of Sciences, academicians of the Chinese Academy of Engineering, directors of national key laboratories, experts and project leaders of some national key research and development plans. The candidate progress will be voted online, and the top 10 progress will be selected as the top ten progress in Chinese science in 2020.

1 Chinese scientists have made outstanding progress in actively responding to the new crown pneumonia epidemic

  In the face of the sudden new crown pneumonia epidemic, Chinese scientists have conscientiously implemented General Secretary Jinping’s important speech on epidemic prevention and control and a series of important instructions and instructions. Under the coordination of the Central Leading Group for Response to the Epidemic and the Joint Prevention and Control Mechanism of the State Council, they have united and cooperated. Race against time, a series of outstanding progress has been made, providing important scientific support for winning the battle against epidemic prevention and control.

  In terms of etiology and epidemiology, the new coronavirus strain was isolated and identified for the first time and the whole genome sequence of the virus was shared with the World Health Organization, laying the foundation for the rapid advancement of diagnostic technology and the development of drug vaccines; clarifying the invasion of new coronavirus cells The key mechanism of my country's national defense system; continued to deepen the study of virus transmission routes to provide scientific and technological support for the optimization of prevention and control strategies; quantitatively evaluated the effects of our national defense control measures.

  In terms of research and development of detection reagents and animal models, at the beginning of the epidemic, the new coronavirus nucleic acid diagnostic reagents were quickly developed, and immunological detection reagents were developed, which provided strong support for pathogen detection; animal models of mice and monkeys infected with the new coronavirus were constructed. , To provide support for drug screening, vaccine research and development, and research on virus transmission mechanisms.

  In terms of drugs and clinical treatment, it has revealed the clinical characteristics of the new crown. In the absence of specific drugs, the combination of Chinese and Western medicine has been implemented. The eighth edition of the national new crown pneumonia diagnosis and treatment plan has been launched, and clinically effective Chinese medicines such as "three drugs and three prescriptions" have been screened out. The treatment methods have been borrowed and used by many countries; the structure of the new coronavirus and key proteins has been analyzed, and the mechanism of action of a batch of Chinese and Western medicines has been revealed; the establishment of shelter hospitals, large-scale nucleic acid testing, and big data tracking and traceability sciences have been proposed. The prevention and control program has increased the admission rate and cure rate, and reduced the infection rate and mortality rate.

  In terms of vaccine and neutralizing antibody research and development, inactivated vaccines, viral vector vaccines, protein subunit vaccines, nucleic acid vaccines, etc. have been developed at the same time. Adenovirus vector vaccines are the first to carry out phase I clinical trials in the world, and inactivated vaccines are global Take the lead in carrying out Phase III clinical trials and get approval for listing with conditions; identify and create a series of neutralizing monoclonal antibodies targeting the new crown spike protein S and receptor binding domain RBD, forming an anti-viral "cocktail" Chinese antibody combination program.

  Through unremitting efforts and selfless dedication, and through rigorous and efficient scientific research, Chinese scientists have provided strong scientific support for my country to achieve major strategic results in the fight against the new crown pneumonia epidemic.

 2 For the first time, Chang'e 5 realized automatic lunar surface sampling and return

  On November 24, 2020, the Chang'e-5 probe was launched at the Wenchang Space Launch Site in Hainan, and was directly sent into the Earth-Moon transfer orbit by the Long March V carrier rocket; after that, the probe experienced Earth-Moon transfer, near-moon braking, and circumlunar Flight, lunar landing, lunar sampling and packaging, lunar takeoff, lunar orbital rendezvous and sample transfer, lunar-ground incident, lunar-ground transfer and re-entry and recovery, etc. The flight phases lasted for 23 days. The Siziwang Banner of Inner Mongolia landed safely in the scheduled area.

Xi Jinping, General Secretary of the Central Committee of the Communist Party of China, President of the State and Chairman of the Central Military Commission, called on behalf of the Party Central Committee, the State Council and the Central Military Commission to congratulate the lunar exploration project Chang'e-5 mission on the complete success.

  As my country’s most complex aerospace system project with the largest technological span, Chang'e 5 completed the first extraterrestrial celestial body sampling and packaging, the first extraterrestrial celestial surface take-off, the first unmanned lunar orbital rendezvous and docking and sample transfer, and the first lunar-ground incident and encapsulation. Many major technological breakthroughs in the history of my country's aerospace, such as carrying lunar samples back into the earth at a high speed, finally realized the first return of samples from extraterrestrial objects in my country.

The complete success of the automatic lunar surface sampling and return mission of Chang'e 5 marks the successful conclusion of the three-step plan of my country's lunar exploration project to orbit, fall, and return. It is a big step forward for China's aerospace industry and will deepen the mankind’s approach to the moon. Contribute to scientific understanding of the cause and evolution of the solar system.

  3 "Struggle" creates a new record for China's manned deep diving

  The development of the "Struggle" all-sea deep manned submersible is a major research task in the field of key deep-sea technology and equipment in my country's "13th Five-Year Plan". The project was initiated in 2016.

In June 2020, "Struggle" completed the final assembly integration and tank test.

In July 2020, the Struggle completed the first phase of the sea trial, with a total of 17 dives and a maximum dive depth of 4548 meters.

On October 10, 2020, the Struggle set sail for the Mariana Trench for the second phase of the sea trial. A total of 13 dives were completed during the period, of which 11 people and 24 people participated in 8 deep dives with a depth of more than 10,000 meters. test.

At 8:12 on November 10, the "Struggle" created a depth record of 10,909 meters for manned deep diving in China.

  China Shipbuilding Institute 702 is the lead unit in the development of the Struggle. It has played a core role in the overall design of the submersible, research and development of key technologies, integrated construction and test verification, and has created an independent full-sea deep manned manned. The deep-submersible equipment design technology system has established a stable and reliable high-standard, standardized test, inspection and application system, and further made major breakthroughs in key technologies such as overall design and optimization of submersibles, system debugging and simulation, and deep-sea operations. It is the first time to conquer the preparation and welding technology of high-strength and high-toughness titanium alloy materials, realize the independent control of the new technology of 10,000-meter-level buoyancy material solidification and molding, and further improve the level of core technologies such as submersible power, propeller, underwater acoustic communication, and intelligent control.

  As the only manned deep submersible equipment in the world that can carry three people multiple times to and from deep sea operations at the same time, the success of its development and sea trials has significantly improved the independent innovation level of my country’s deep-sea equipment and technology, making my country It has the ability to enter the deepest part of the world's oceans to carry out scientific exploration and research, which reflects my country's comprehensive strength in the field of marine high-tech, and is an important milestone in my country's deep-sea scientific and technological exploration.

 4 Reveal the key steps in the transmission of human genetic material

  DNA replication is the basis for the precise transmission of human genetic material between cells. People are not clear about the specific process of identifying the DNA replication initiation site in higher organisms, which also hinders people’s understanding of the mechanism of cancer occurrence and development. understanding.

Li Guohong's team from the Institute of Biophysics, Chinese Academy of Sciences and his collaborators revealed a fine-grained mechanism for identifying and regulating the origin of DNA replication.

The study found that the histone variant H2A.Z can promote the dimethylation modification of the twentieth amino acid of histone H4 by binding to the histone methyltransferase SUV420H1.

The H2A.Z nucleosomes with dimethylation modification can further recruit the replication initiation site recognition protein, thereby helping to identify the DNA replication initiation site.

The study further found that the replication initiation site regulated by the H2A.Z-SUV420H1-H4K20me2 pathway has strong replication activity and is biased to be activated and used early in the replication period.

After disrupting this regulatory mechanism in cancer cells, the DNA replication and cell growth of cancer cells are inhibited.

After destroying this regulatory mechanism in T cells, the immune activation of T cells is also suppressed.

  This study describes a novel epigenetic regulation mechanism of DNA replication mediated by H2A.Z, providing a new perspective for understanding the identification of DNA replication start sites in higher organisms, and for solving the long-standing eukaryotic DNA replication The choice of starting point makes an important contribution to the problem of starting.

 5 Developed a transparent ferroelectric single crystal with ultra-high voltage electrical properties

  Relaxation ferroelectric single crystal [Pb(Mg1/3Nb2/3)O3-PbTiO3, PMN-PT] has excellent piezoelectric effect and has been widely used in ultrasonic imaging, sonar equipment, and microelectromechanical systems (MEMS).

However, since it was discovered more than 20 years ago, there has been no new breakthrough in piezoelectric performance, and due to the existence of ferroelectric domain walls, its light transmittance is low, which cannot meet the current development needs of piezoelectric devices with multiple functions and high sensitivity. , There is an urgent need for new theories and design methods.

  The research team of Professor Xu Zhuo from Xi’an Jiaotong University revealed the origin of the high-voltage electrical effect of the relaxation ferroelectric single crystal, and developed a samarium-doped PMN-PT single crystal, which has a piezoelectric performance of more than 4000pC/N, compared with undoped Single crystal has doubled.

On this basis, the use of electrical domain structure control eliminates the ferroelectric domain wall that scatters light in the single crystal. For the first time, high-voltage electrical properties and high light transmittance are obtained in PMN-PT single crystals. For a long time, the two are difficult to coexist international problems.

  Its piezoelectric coefficient is 100 times higher than that of the existing transparent piezoelectric single crystal LiNbO3, the electro-optical coefficient can be increased by up to 40 times, and it also has a higher anti-light damage threshold and nonlinear optical effects.

This transparent ferroelectric single crystal can greatly improve the imaging resolution of photoacoustic imaging systems in the diagnosis of breast cancer, melanoma and blood diseases. It also provides a great opportunity for the development of high-performance electro-optic modulators, optical phased arrays, and quantum optical devices. A brand new key material.

This single crystal material with excellent electro-optic, acousto-optic and acousto-optic-electric coupling effects is expected to further open up more new application areas.

  6 2020 Mount Everest elevation determination

  The height of Mount Everest has been paid attention to for a long time, and the height of Mount Everest has been accurately measured and announced to the world, demonstrating the country's comprehensive strength and technological level.

In the 2020 Mount Everest elevation survey, the Chinese team of scientists comprehensively used a variety of modern surveying and mapping technologies to achieve a number of major technological innovation breakthroughs, and obtained the highest-precision Mount Everest elevation results in history.

  For the height measurement of Mount Everest, Beidou satellite positioning technology and domestically-made measurement equipment have fully taken the lead for the first time, and the application of domestically-made measurement equipment has achieved a major breakthrough.

For the first time, the ground gravity measurement of the summit was completed, and the first gravity measurement result of the summit of Mount Everest in human history was obtained, which helped to improve the accuracy of the height measurement of Mount Everest.

The team of scientists overcame the extreme weather and harsh environment in the Mount Everest region, and for the first time achieved a historic breakthrough in the airborne gravity, optical and laser remote sensing measurement of 12,700 square kilometers on the summit of Mount Everest and the surrounding area, filling the gap in gravity data in the Mount Everest region. Improved the accuracy of Mount Everest elevation measurement.

Compared with the elevation survey of Mount Everest in 2005, the accuracy of the geoid in the Mount Everest area has increased by 300%.

The scientific and technological cooperation between Chinese and Nepalese scientists has established the geoid of the Everest region based on the global elevation benchmark for the first time, and jointly determined the elevation of the snow surface of Mount Everest based on the global elevation benchmark of 88.886 meters for the first time in history. President Xi Jinping and the Nepalese president class Dali exchanged letters and jointly announced the latest elevation of Mount Everest, which won wide acclaim from the international community.

  In addition, the abundant observation data obtained by the Everest survey will provide valuable resources for the ecological environment protection restoration, natural resource management, geological research and survey, crustal movement monitoring, climate change, and glacier and frozen soil research in the Everest region. , Informative first-hand information.

7 The ancient genome reveals the evolution and migration history of the Chinese population in the past ten thousand years

  In the field of international paleogenomics, the paleogenome research on East Asia, especially the prehistoric population in China, is very scarce.

The research team of Fu Qiaomei from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences first carried out the largest, large-scale, and systematic paleogenome study of prehistoric populations in northern and southern China, and successfully obtained 11 sites in northern and southern my country through cutting-edge experimental methods25 The genomes of an individual between 9500-4200 years ago and a 300-year-old individual reveal the pattern of north-south differentiation, subject continuity, and migration and integration history of the Chinese population since 9500.

  The study found that the main population in the north and south of China had diverged 9500 years ago, but the evolution of the population in the same period in the south and north was basically continuous, and was not affected by obvious foreign populations. Migration interactions mainly occurred between the populations in the East Asian region; in addition, it was clear that The Austronesian language group, represented by the aborigines of Taiwan Island and widely distributed in the Pacific islands, originated in the southern coastal areas of China and can be traced back to 8400 years ago.

This achievement fills in the gaps in important information about the genetics, evolution, and adaptation of prehistoric humans in the East, especially in China, and has made important scientific contributions to clarifying the formation process of the Chinese nation and revising the evolutionary model of the population in the south of East Asia.

 8 Big data portrays the 300 million-year history of the earth’s biodiversity evolution with the highest precision so far

  The origin and evolution of life is one of the ten scientific mysteries in the world.

More than 99% of the creatures that have lived on the earth have been extinct. Rebuilding the history of the earth's biodiversity through fossil records is one of the most important ways to understand the current status and future trends of biodiversity.

  However, the low time resolution and coarse classification of the earth's biodiversity in the geological historical period cannot accurately identify sudden major biological evolution events, nor can it provide an important reference for the evolution of modern earth ecosystems.

The team of Shen Shuzhong and Fan Junxuan of Nanjing University, together with domestic and foreign experts, created an international large-scale database, independently developed artificial intelligence algorithms, and made breakthroughs by using "Tianhe-2" supercomputing, and obtained the world's first high-precision Paleozoic marine biodiversity of more than 300 million years Evolution curve, time resolution is more than 400 times higher than similar international research.

The new curve accurately depicts the many major extinctions, recovery and radiation events in the evolution of the Earth's biodiversity, revealing the synergistic relationship between the changes in biodiversity, atmospheric CO2 content, and global climate change at that time.

This research will promote the transformation of the entire evolutionary paleontology research.

 9 In-depth analysis of the markers and intervention targets of multi-organ aging

  With the increasing degree of population aging, in-depth research on aging and scientific responses to population aging are major national needs in the new era.

Focusing on core scientific issues such as the mechanism and intervention of aging, the Liu Guanghui research group and Qu Jing research group of the Institute of Zoology, Chinese Academy of Sciences, the Zhang Weiqi research group of the Beijing Institute of Genomics, Chinese Academy of Sciences, and the Tang Fuchou research group of Peking University jointly tackle key problems, using multidisciplinary cross-cutting The method has revealed new biological markers and adjustable targets for mammalian multi-organ aging at the system level.

  In terms of the analysis of the aging mechanism, the study found that the imbalance of redox pathway homeostasis is the main molecular feature of primate ovarian aging, which provides new biological markers for evaluating ovarian aging and decline in female fertility, as well as looking for measures to delay ovarian aging And the development of intervention strategies for related diseases provides new ideas.

  In terms of aging intervention, the study clarified that calorie restriction ("seven percent full") can delay the aging of multiple organs by regulating the immune inflammatory pathways in various tissues of the body, and reveal the new molecular mechanism between metabolic intervention, immune response and healthy lifespan. Scientific connection.

These research results have deepened people's understanding of the heterogeneity and complexity of organ aging, and laid an important foundation for the establishment of early warning and scientific response strategies for aging and aging-related diseases.

  10 Experiments have observed quantum interference in chemical reactions

  The process of chemical reaction is accompanied by complex quantum mechanical phenomena, but it is usually difficult to directly observe, so the nature of chemical reaction is also difficult to get a thorough understanding.

The research team of Academician Yang Xueming, Academician Zhang Donghui, Sun Zhigang and Xiao Chunlei of Dalian Institute of Chemical Physics, Chinese Academy of Sciences provided a research example.

They found that in the H+HD→H2+D reaction, the backscattering of the product H2 (v'=2, j'=3) exhibited significant oscillations within the range of collision energy of 1.9-2.2 electron volts ( Where v'is the vibrational quantum number and j'is the rotational quantum number).

Through topological analysis, it is found that the reaction has two completely different reaction paths, and the oscillation is caused by the quantum mechanical interference between the two paths.

The study revealed that the quantum geometric phase effect of the reaction still exists at a lower energy and can be observed.

This is very similar to the well-known Aharonov-Bohm effect, which clearly reveals the quantum nature of chemical reactions.

  This edition of the manuscript was compiled by our reporter Liu Yin, and the material was provided by the High-Tech Research and Development Center (Basic Research Management Center) of the Ministry of Science and Technology