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Physical properties of relativistic electron beam during long-range propagation in space plasma environment

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Chinese Physics B 2021年第10期30卷 283-291页

作者： bi-Xi Xue Jian-hong Hao Qiang Zhao Fang Zhang jie-Qing Fan Zhi-Wei Dong School of Electrical and Electronic Engineering Department North China Electric Power UniversityBeijing 102206China Institute of Applied Physics and Computational Mathematics Beijing 100094China

It is known that ion channel can effectively limit the radial expansion of an artificial electron beam during its longrange propagation in the space plasma *** prior studies discussed the focusing characteristics of the beam in the ion channel,but the establishment process and transient properties of the ion channel itself,which also plays a crucial role during the propagation of the relativistic electron beam in the plasma environment,were commonly *** this study,a series of two-dimensional(2D)particle-in-cell simulations is performed and an analytical model of ion channel oscillation is constructed according to the single-particle *** results showed that when the beam density is higher than the density of plasma environment,ion channel can be established and always continues to oscillate periodically over the entire *** factors,including the beam electron density,initial beam radius,and the plasma density can affect the oscillation properties of ion *** velocity of the beam oscillates synchronously with the ion channel and this phenomenon will finally develop into a two-stream instability which can seriously affect the effective transport for relativistic electron *** appropriate beam parameters based on various plasma environments may contribute to the improvement of the stability of ion ***,radial expansion of the beam can be limited by ion channel and a stable long-range propagation in terrestrial atmosphere may be achieved.

关键词： ion channel space plasma environment long-range propagation particle-in-cell(PIC)simulation

How to disentangle microbially functional complexity: an insight from the network analysis of C, N, P and S cycling genes

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Science Bulletin 2019年第16期64卷 1129-1131页

作者： Bang-Xiao Zheng Yi Zhao Qing-Fang bi Guo-Wei Zhou hong-jie Wang Xiu-Li Hao Kai Ding Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Faculty of biological and Environmental Sciences Ecosystems and Environment Research ProgrammeUniversity of HelsinkiNiemenkatu 73FI-15140 LahtiFinland Section for Microbial Ecology and biotechnology Department of Plant and Environmental SciencesUniversity of CopenhagenThorvaldsenvej 40DK-1871 Frederiksberg CDenmark Key Laboratory of Subtropical Soil Science and Plant Nutrition of Zhejiang Province College of Environmental&Resource SciencesZhejiang UniversityHangzhou 310058China Department of Microbiology and Ecosystem Science Research Network'Chemistry Meets Microbiology’University of ViennaVienna A-1090Austria State Key Lab of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Microbial Ecophysiology Group Faculty of Biology/ChemistryUniversity of BremenD-28359 BremenGermany Institute for Environmental Genomics University of OklahomaNormanOK 73019USA State Key Laboratory of Agricultural Microbiology Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Arable Land Conservation(Middle and Lower Reaches of Yangtze River) Ministry of AgricultureCollege of Resources and EnvironmentHuazhong Agricultural UniversityWuhan 430070China

A complete ecosystem is also a complex network in which multifarious species interact with each other to achieve system-level functions, such as nutrient biogeochemistry (1)Microbial community is commonly considered as the primary driving force of ecosystem nutrient mobilization and metabolism, especially carbon (C), nitrogen (N), phosphorus (P), sulfur (S) and methane coupling process (2)The rise of metagenomics and high-throughput array (e.g. PhyloChip, GeoChip, etc.

关键词： net P and S cycling genes an insight from the network analysis of C How to disentangle microbially functional complexity

Ion-focused propagation of a relativistic electron beam in the self-generated plasma in atmosphere

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Chinese Physics B 2022年第6期31卷 334-341页

作者： Jian-hong Hao bi-Xi Xue Qiang Zhao Fang Zhang jie-Qing Fan Zhi-Wei Dong School of Electrical and Electronic Engineering Department North China Electric Power UniversityBeijing 102206China Institute of Applied Physics and Computational Mathematics Beijing 100094 China

It is known that ion-focused regime(IFR)can effectively suppress expansion of a relativistic electron beam(REB).Using the particle-in-cell Monte Carlo collision(PIC-MCC)method,we numerically investigate the propagation of an REB in neutral *** results demonstrate that the beam body is charge neutralization and a stable IFR can be *** a result,the beam transverse dimensions and longitudinal velocities keep close to the initial *** also calculate the charge and current neutralization factors of the *** with envelope equations,we obtain the variations of beam envelopes,which agree well with the PIC ***,both the energy loss and instabilities of the REB may lead to a low transport efficiency during long-range *** is proved that decreasing the initial pulse length of the REB can avoid the influence of electron *** parts of REB pulses to build a long-distance IFR in advance can improve the beam quality of subsequent ***,a long-distance IFR may contribute to the implementation of long-range propagation of the REB in space environment.

关键词： ion-focused regime(IFR) charge neutralization electron avalanche relativistic electron beam(REB) particle-in-cell Monte Carlo collision(PIC-MCC)

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Paths out of poverty

Journal of Integrative Agriculture 2021年第4期20卷 851-856页

作者： NIE Feng-ying bi jie-ying Apurv MARU Agricultural Information Institute Chinese Academy of Agricultural Sciences(CAAS)Beijing 100081 P.R.China

Introduction Ending poverty in all its forms everywhere is the first Sustainable Development Goal(SDG) of the United Nations(2021a). Progress towards this goal has varied but also been fruitful. Between 1990 and 2015, over a billion people were lifted out of extreme poverty(World Bank 2018). From 36% of the population under extreme poverty in 1990 to 10% in 2015(United Nations 2021b).

关键词： Sustainable extreme poverty

Behavior of Phrynocephalus frontalis to Avoid Traps

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Asian Herpetological Research 2017年第1期18卷 55-60页

作者： Mingxia FU Shaoyong CHEN Zhichao HE Zhiliang jie Junhuai bi College of Life Sciences Inner Mongolia Normal University Hohhot 010022 Inner Mongolia China

Previous studies have shown that reptiles are capable of spatial learning and learn to locate important environmental resources so that they can return to those locations at a future time, when needed. Lizards improve their adaptability and survival by learning the position of their shelter in a complex environment. This behavior raises the question, whether lizards can sense danger, such as a trap, in their surroundings, by determining the location of the trap and avoiding it. In the present study, we used a pitfall trap to test if steppe toad-headed agama, Phrynocephalus frontalis, can learn to recognize the position of the trap and avoid it. Our results revealed that the percentage of activity time in the trap area was significantly reduced （P 〈 0.001） and the time of drop trap was also significantly reduced （P = 0.00631）. The number of burrows dug by lizards distributed in the trap area was the least. Reduced activity time in the trap area was observed to have no obvious relationship with the drop in the number of burrows. The present study, therefore, demonstrates that P. frontalis are capable of learning the avoidance of a trap by locating its position. The findings offer significant insight in the understanding of reptilian behavior, which is important in the study of the role of reptiles in global ecology, especially because they are often very sensitive to environmental changes.

关键词： reptiles escape spatial learning Phrynocephalusfrontalis fitness

Validation of Column-Averaged Dry-Air Mole Fraction of CO_2 Retrieved from OCO-2 Using Ground-Based FTS Measurements

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Journal of Meteorological Research 2018年第3期32卷 433-443页

作者： Yanmeng bi Qian WANG Zhongdong YANG jie CHEN Wenguang BAI National Satellite Meteorological Center China Meteorological Administration

In order to correctly use the column-averaged atmospheric COdry-air mole fraction(XCO) data in the COflux studies, XCOmeasurements retrieved from the Orbiting Carbon Observatory-2(OCO-2) in 2015 were compared with those obtained from the global ground-based high-resolution Fourier Transform Spectrometer(FTS) participating in the Total Carbon Column Observing Network(TCCON). The XCOretrieved from three observing modes adopted by OCO-2, i.e., nadir, target, and glint, were separately validated by the FTS measurements at up to eight TCCON stations located in different areas. These comparisons show that OCO-2 glint mode yields the best qualitative estimations of COconcentration among the three operational approaches. The overall results regarding the glint mode show no obvious systematic biases. These facts may indicate that the glint concept is appropriate for not only oceans but also land regions. Negative systematic biases in nadir and target modes have been found at most TCCON sites. The standard deviations of XCOretrieved from target and nadir modes within the observation period are similar, and larger than those from glint mode. We also used the FTS site in Beijing, China, to assess the OCO-2 XCOin 2016. This site is located in a typical urban area, which has been absent in previous studies. Overall, OCO-2 XCOagrees well with that from FTS at this site. Such a study will benefit the validation of the newly launched TanSat products in China.

关键词： Orbiting Carbon Observatory-2(OCO-2) Fourier Transform Spectrometer(FTS) carbon dioxide(CO2) validation

Transition Metal Catalyzed Direct Oxidative Borylation of C--H Bonds

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Chinese Journal of Chemistry 2018年第10期36卷 950-954页

作者： Zhong-Tao Jiang bi-qin Wang Zhang-jie Shi College of Chemistry and Materials Science Sichuan Normal University Chengdu Sichuan 610068 China Department of Chemistry Fudan University Shanghai 200433 China

Organoboron is well-developed and broadly utilized organometallic reagents in organic synthesis due to its extraordinary performances in transition-metal catalyzed C-C and C-X bonds construction. Catalytic C--H borylation and further transformations catalyzed by transition metal catalysts in the absence of oxidants were well studied in decades. However, as known, transition metal catalyzed oxidative C-H borylations were not reviewed up to date. In this article the oxidative borylation of C（sp2）-H and C（sp3）-H bonds were summarized and their mechanisms were also accounted.

关键词： C-H borylation oxidation organoboron transition metal catalysis

Clinicopathologic Characteristics and Prognosis Analysis of Marjolin's Ulcer in 40 Cases

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Current Medical Science 2018年第6期38卷 1038-1044页

作者： bi-wei GUO Teng PAN hong-bo CHEN Li ZHU Meng TIAN jie-cong WANG Xiao-dan LI Department of Plastic Surgery Department of DermatologyUnion HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Anesthesiology Jining No.1People's Hospital Jining 272000China The Ninth Department of Plastic Surgery Plastic Surgery HospitalChinese Academy of Medical SciencesBeijing100144 China 不详

Marjolin's ulcer (MU)is a rare but aggressive epidermoid carcinoma observed in scars or *** article provides comprehensive characteristics and prognostic details of MU. Clinical data of 40patients with MU between January 2010 and December 2017 were analyzed *** cell carcinoma was the most common pathological type (35/40,87.5%). Extended resection was performed to treat all cases with skin grafting or flap ***-up duration ranged from 6 to 96 months (median,52 months)and recurrence was noted in 9 *** 1-,3-and 5-year recurrence-free survival (RFS)rates were 87.2%,87.2%,83.2%respectively and the recurrence rate was 22.5%.Univariate analysis revealed that cause of scars (P=0.044),lesion appearance (P=0.036),ultraviolet radiation exposure (P=0.000),depth (P=0.001)and histological grade (P=0.027)had a statistically significant correlation with prognosis of *** analysis revealed that depth (P=0.034,RR=2,681,95%CI:1.077-6.674)and histological grade (P=0.008,RR=2.820,95%CI:1.3156.050)were independent prognostic factors for *** conclusion,superficial infiltration and high-grade differentiation predict more favorable prognosis. Careful follow-up of high-risk groups is strongly recommended to prevent recurrence and improve prognosis.

关键词： Marjolin's ulcer clinicopathological pattern prognosis

Serum Total bilirubin and Risk of Progressing Diabetes:A Prospective Cohort Study

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biomedical and Environmental Sciences 2021年第8期34卷 632-636页

作者： ZHANG jie ZHANG Yin Fei HU Chun Yan ZHANG Yi QI hong Yan LIN Lin XU Yu XU Min LU jie Li bi Yu Fang WANG Wei Qing NING Guang CHEN Yu hong Department of Endocrine and Metabolic Diseases Shanghai Institute of Endocrine and Metabolic DiseasesRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Shanghai National Clinical Research Center for Metabolic Diseases Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of ChinaShanghai National Center for Translational MedicineRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Department of Endocrinology Jiading Central HospitalShanghai University of Medicine&Health SciencesShanghai 201800China

Diabetes has become a serious public health concern worldwide,and China is the epidemic *** China,the prevalence of type 2 diabetes(T2D)was 11.6%among adults aged≥18 years[1].Cardiovascular disease(CVD)occurs earlier and with greater severity in patients with T2D than in individuals without T2D[2].Thus,potential risk factors for screening T2D are needed to prevent such poor clinical outcomes.

关键词： Diabetes Serum clinical