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Integrative Zoology 2024年第3期19卷 458-467页

作者： Roman SHARNUUD Eric I.AMECA MOE Key Laboratory for Biodiversity Science&Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijingChina Climate Change Specialist Group Species Survival CommissionInternational Union for Conservation of NatureGlandSwitzerland

A significant research focus is placed on identifying animal species and areas at future risk to human-induced alterations of the environment and long-term changes in climatic ***,the extent to which exposure to extreme climatic events and intense human pressure can increase the risk of harmful impacts on species remains poorly *** on terrestrial mammals in China,one of the world’s megadiverse countries,we investigated patterns of contemporary exposure to floods and human pressures and determined their taxonomic representation and distribution across three major area-based conservation schemes,namely,national nature reserves(NNRs),priority areas for biodiversity conservation(PABCs),and key biodiversity areas(KBAs).Among the 440 species assessed with moderate or high exposure to floods,327(∼75%)also qualified as moderate or high in exposure to intense human *** species mainly belong to the orders Chiroptera,Eulipotyphla,and ***,there were 305,311,and 311 species with moderate or high exposure to flood and intense human pressure represented across NNRs,PABCs,and KBAs,*** findings support the prioritization of KBAs for expansion of site-based protection efforts such as NNRs in China,considering threats to species from exposure to adverse effects from both extreme climate and human pressure.

关键词： conservation floods human pressure mammals taxonomy

High-throughput fluorescent screening of thioredoxin reductase inhibitors to inhibit Mycobacterium tuberculosis

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Chinese Chemical Letters 2024年第3期35卷 358-362页

作者： Fei Yan Xin Zhao Ruibo Li Xiuyan Han Qiulong Yan Lei Feng Xiulan Xin Jingnan Cui Xiaochi Ma Second Affiliated Hospital Dalian Medical UniversityDalian 116044China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China Jiangsu Key Laboratory of New Drug research and Clinical Pharmacy Xuzhou Medical UniversityXuzhou 221004China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China College of Bioengineering Beijing PolytechnicBeijing 100029China

Tuberculosis(TB)is a chronic infectious disease,which is caused by the pathogen Mycobacterium tuberculosis(Mtb)and reemerged as a global health risk with a significant proportion of multi-drug resistant and extensively drug resistant TB *** is very urgent to find some novel high-confidence drug targets in Mtb for discovering the effective anti-TB *** reductase(TrxR)has been identified to be a highly viable target for anti-TB drugs for its important role in protecting the pathogen from thiol-specific oxidizing stress,regulating intracellular dithiol/disulfide homeostasis and DNA replication and *** the present work,a near-infrared(NIR)fluorescent probe DDAT was developed for the detection of TrxR activity and used to high-throughput screen the TrxR inhibitors from natural *** screened TrxR inhibitors from Sappan Lignum and microbial metabolites that were further used to inhibit Mycobacterium *** the results indicate that DDAT is a practical fluorescent molecular tool for the discovery of potential anti-TB drugs.

关键词： Thioredoxin reductase NIR fluorescent probe Fluorescence imaging High-throughput screening inhibitors Inhibit Mycobacterium tuberculosis

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Geometry characteristics and wide temperature behavior of silicon-based GaN surface acoustic wave resonators with ultrahigh quality factor

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Science China(Information Sciences) 2024年第2期67卷 267-278页

作者： Guofang YU Renrong LIANG Haiming ZHAO Lei XIAO Jie CUI Yue ZHAO Wenpu CUI Jing WANG Jun XU Jun FU Tianling REN School of Integrated Circuits Tsinghua University beijing National research Center for Information Science Technology Tsinghua University

Surface acoustic wave(SAW) resonators with an ultrahigh Q-factor are designed and fabricated on silicon-based gallium nitride(GaN/Si). The temperature-dependent performance is characterized over a wide range, from 10 to 500 K. Finite element analysis is employed to guide the design of the SAW resonator from indications of the Rayleigh mode and weak propagation direction dependence of SAW in the c-plane of GaN/Si. The SAW resonator with 100 pairs of interdigital transducers(IDT), 100 pairs of grating reflectors(GR) for each side, aperture size of 80 μm, metallization ratio of 0.5, and electrode width of 500 nm resonates at 1.9133 GHz accordingly with an ultrahigh Q-factor of 7622 at room temperature, which contributes the fr× Qr, up to 14.583×1012Hz. A resonator operating over 10 to 500 K indicates an approximately linear decreasing temperature dependence above 280 K while being approximately constant below 40 K. The fitting to resonator characteristics using the modified Butterworth Van Dyke(m BVD) model reveals a reduction in both the electrode and mechanical losses while worsening the dielectric loss with cooling down.

关键词： GaN/Si SAW resonator ultrahigh Q-factor temperature-dependent performance mBVD losses

Frequency and size change of ice–snow avalanches in the central Himalaya:A case from the Annapurna Ⅱ glacier

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Advances in Climate Change research 2024年第3期15卷 464-475页

作者： Yao LI Yi-Fei CUI Jian-Sheng HAO Zheng-Tao ZHANG Hao WANG Jian GUO Shuo-Fan WANG State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Hydrosphere Sciences of the Ministry of Water Resources Beijing 100084China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of National Safety and Emergency Management Beijing Normal UniversityBeijing 100875China Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Glaciers have retreated and shrunk in High Mountain Asia since the mid-20th century because of global warming,leading to glacier instability and hazardous iceesnow ***,the complex relationship between iceesnow avalanches and factors such as climate and potential triggers are difficult to understand because of the lack of observational ***,we addressed iceesnow avalanches on the Annapurna Ⅱ glacier in Nepal,Central *** constructed an iceesnow avalanche history using long-term multi-source remote sensing images(1988-2021)and mapped the velocity fields of glaciers using cross-correlation analysis on SAR and optical ***,we investigated the impact of climate change and earthquakes on the frequency and size of iceesnow *** results demonstrate that the frequency of iceesnow avalanches has increased from 10 in 1988 to 27 in 2020,but the average area of iceesnow avalanche deposits has decreased by approximately 70%,from 3.4×10^(5) m^(2) in 1988 to 1.2×10^(5) m^(2) in *** evolutionary characteristic of ice avalanches is linked to the impact of glacier retreat(reduction in ice material supply)and increased activity under climate *** glacier movement velocity controls the size of iceesnow avalanches and can be set as an indicator for iceesnow avalanche *** the Annapurna Ⅱ glacier,an iceesnow avalanche occurred when the glacier velocities were greater than 1.5 m d^(-1).These results offer insights into iceesnow avalanche risk assessment and prediction in high-mountain areas,particularly in regions characterised by dense glacier distribution.

关键词： Iceesnow avalanche Glacier instability Climate change Central Himalaya Remote sensing

SnS_(2)nanoparticles embedded in sulfurized polyacrylonitrile composite fibers for high-performance potassium-ion batteries

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Interdisciplinary Materials 2024年第1期3卷 150-159页

作者： Ruiling Li Lijuan Tong Yitong Jiang Yaxin Wang Jing Long Xiaochuan Chen Junxiong Wu Xiaoyan Li Yuming Chen Engineering research Center of Polymer Green Recycling of Ministry of Education Fujian Key Laboratory of Pollution Control&Resource ReuseCollege of Environmental and Resource Sciences and College of Carbon Neutral Modern IndustryFujian Normal UniversityFuzhouFujianChina

Potassium-ion batteries(PIBs)have garnered significant attention as a promising alternative to commercial lithium-ion batteries(LIBs)due to abundant and cost-efficient potassium ***,the large size of potassium ions and the resulting sluggish reaction kinetics present major obstacles to the widespread use of ***,we present a simple method to ingeniously encapsulate SnS_(2)nanoparticles within sulfurized polyacrylonitrile(SPAN)fibers(SnS_(2)@SPAN)for serving as a high-performance PIB *** large interlayer spacing of SnS_(2)provides a fast transport channel for potassium ions during charge–discharge cycles,while the one-dimensional SPAN skeleton offers massive binding sites and shortens the diffusion path for potassium ions,facilitating faster reaction ***,the excellent ductility of SPAN can effectively accommodate the large volume changes that occur in SnS_(2)upon potassium-ion insertion,thereby enhancing the cyclic stability of SnS_(2).Benefiting from the above advantages,the SnS_(2)@SPAN composites exhibit impressive cyclability over 500 cycles at 4 A g−1,with a capacity retention rate close to 100%.This study provides an effective approach for stabilizing high-capacity PIB anode materials with large volume variations.

关键词： electrospinning encapsulation potassium‐ion batteries sulfurized polyacrylonitrile tin disulfide

Single-cell omics:experimental workflow,data analyses and applications

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Science China Life Sciences 2024年

作者： Fengying Sun Haoyan Li Dongqing Sun Shaliu Fu Lei Gu Xin Shao Qinqin Wang Xin Dong Bin Duan Feiyang Xing Jun Wu Minmin Xiao Fangqing Zhao Jing-Dong J.Han Qi Liu Xiaohui Fan Chen Li Chenfei Wang Tieliu Shi Center for Bioinformatics and Computational Biology Shanghai Key Laboratory of Regulatory Biology the Institute of Biomedical Sciences and School of Life Sciences East China Normal University beijing Institutes of Life Science Chinese Academy of Sciences Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary Studies Center for Quantitative Biology (CQB) Peking University Zhejiang Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases Women’s Hospital Zhejiang University School of Medicine Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOE School of Statistics East China Normal University Shanghai 200062 China Department of Clinical Laboratory the Affiliated Wuhu Hospital of East China Normal University (The Second People's Hospital of Wuhu City) Pharmaceutical Informatics Institute College of Pharmaceutical Sciences Zhejiang University Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration (Tongji university) Ministry of Education Orthopaedic Department Tongji Hospital Bioinformatics Department School of Life Sciences and Technology Tongji University Frontier Science Center for Stem Cells School of Life Sciences and Technology Tongji University Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine Shanghai East Hospital Bioinformatics Department School of Life Sciences and Technology Tongji University research Institute of Intelligent Computing Zhejiang Lab Shanghai research Institute for Intelligent Autonomous Systems Center for Single-cell Omics School of Public Health Shanghai Jiao Tong University School of Medicine National Key Laboratory of Chinese Medicine Modernization Innovation Center of Yangtze River Delta Zhejiang University

Cells are the fundamental units of biological systems and exhibit unique development trajectories and molecular features. Our exploration of how the genomes orchestrate the formation and maintenance of each cell, and control the cellular phenotypes of various organismsis, is both captivating and intricate. Since the inception of the first single-cell RNA technology, technologies related to single-cell sequencing have experienced rapid advancements in recent years. These technologies have expanded horizontally to include single-cell genome, epigenome,proteome, and metabolome, while vertically, they have progressed to integrate multiple omics data and incorporate additional information such as spatial scRNA-seq and CRISPR screening. Single-cell omics represent a groundbreaking advancement in the biomedical field,offering profound insights into the understanding of complex diseases, including cancers. Here, we comprehensively summarize recent advances in single-cell omics technologies, with a specific focus on the methodology section. This overview aims to guide researchers in selecting appropriate methods for single-cell sequencing and related data analysis.

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Temporal and spatial changes of residential land in the Yuyang desert region of northern Shaanxi Province in recent 20 years

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Frontiers of Earth Science 2012年第3期6卷 250-260页

作者： Xiangsheng YI Yanyu YIN Yaojie YUE Laboratory of Regional Geography School of Geography Beijing Normal University Beijing 100875 China Institute of Geographic-Sciences and-Natural Resources research Chinese Academy of Sciences Beijing 100101 China

It is very important to understand the temporal and spatial changes of residential land for the improvement of human settlement environment. Based on the three TM images of 1986, 1996 and 2005 and other assistant maps, the temporal and spatial characteristics of residential land in the Yuyang desert region of northern Shaanxi Province of China were analyzed by using geographical information System （GIS） and remote sensing （RS） technology. Some important conclusions were obtained, which mainly contained four aspects as follows. 1） The area of residential land in the Yuyang desert region increased 956.07 hm2 in total, and the changes of residential land among the townships were different with four various change trends. The expansion speeds in the Yuyang Township and Qinhe Township were the biggest from 1986 to 1996 and from 1996 to 2005, respectively. The expansion intensities in other townships were below 0.1%, except the Yuyang Township. 2） The number of residential land patches increased 2847, while the average area and perimeter of residential land patches decreased 0.304 hm2 and 60.78 m during 1986-2005, respectively. The residential land patches also displayed four different changes from 1986 to 2005 among the townships. 3） The residential land mainly distributed in the middle of Yuyang Township and Mahe Township, and the interface of Jinjitan Township and Mengjiawan Township. The total spatial pattern of residential land was relative stability, but the significant changes of residential land were found in the Yuyang Township and its vicinities during 1986-2005. 4） Three distribution patterns of residential land at the micro scale were categorized from the 100 typical villages in the study area. The number of villages in the pattern 1 increased, while the pattern 2 and pattern 3 decreased in recent 20 years, which implicated the adaptation of humans to the habitation environment. This research would provide scientific references fbr harmonizing the human-land r

关键词： residential land temporal change spatialpattern Yuyang desert region

Bi-directional Control of Synaptic Input Summation and Spike Generation by GABAergic Inputs at the Axon Initial Segment

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Neuroscience Bulletin 2023年第1期39卷 1-13页

作者： Ziwei Shang Junhao Huang Nan Liu Xiaohui Zhang State Key Laboratory of Cognitive Neuroscience and Learning IDG/McGovern Institute for Brain ResearchBeijing Normal UniversityBeijing 100875China

Differing from other subtypes of inhibitory interneuron,chandelier or axo-axonic cells form depolarizing GABAergic synapses exclusively onto the axon initial segment(AIS)of targeted pyramidal cells(PCs).However,the debate whether these AIS-GABAergic inputs produce excitation or inhibition in neuronal processing is not *** realistic NEURON modeling and electrophysiological recording of cortical layer-5 PCs,we quantitatively demonstrate that the onset-timing of AIS-GABAergic input,relative to dendritic excitatory glutamatergic inputs,determines its bi-directional regulation of the efficacy of synaptic integration and spike generation in a *** specifically,AIS-GABAergic inputs promote the boosting effect of voltage-activated Na+channels on summed synaptic excitation when they precede glutamatergic inputs by>15 ms,while for nearly concurrent excitatory inputs,they primarily produce a shunting inhibition at the ***,our findings offer an integrative mechanism by which AIS-targeting interneurons exert sophisticated regulation of the input-output function in targeted PCs.

关键词： GABAergic inputs Axon initial segment Synaptic integration Axo-axonic cell Chandelier cell NEURON simulation Dynamic clamp

Accuracy assessment of global historical cropland datasets based on regional reconstructed historical data——A case study in Northeast China

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Science China Earth Sciences 2010年第11期53卷 1689-1699页

作者： Li BeiBei Fang XiuQi Ye Yu Zhang XueZhen beijing normal Univ Sch Geog Beijing 100875 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China

Historical cropland datasets are fundamental for quantifying the effects of human land use activities on climatic change and the carbon cycle. Two representative global land-use datasets, the Global Land Use Database (termed SAGE dataset) and the Historical Database of the Global Environment (termed HYDE dataset) have been established and used widely. Despite improvement of data quality and methodologies for extracting historical land use information, certain dataset limitations exist that need to be quantified and communicated to users so that they can make informed decisions on whether and how these land-use products should be used. The Cropland data of Northeast China (CNEC) is based on calibrated historical data and a multi-sourced data conversion model, and reconstructs cropland cover change in Northeast China over the last 300 years. Us- ing the CNEC as a reference, we evaluated the accuracy of cropland cover for SAGE and HYDE in Northeast China at spatial scales ranging from the entire Northeast China to provinces and even individual raster grid cells. Neither SAGE nor HYDE reflects real historical land reclamation. Cropland areas in SAGE are overestimated by 20.98 times in 1700 to 1.6 times in 1990. Although HYDE is better, there are significant disagreements in cropland area and distribution between HYDE and CNEC, especially in the 18th and 19th centuries. The proportion of total grid cells whose relative error was greater than 100% was 63.55% in 1700 and 53.27% in 1780. Global cropland dataset errors over Northeast China originate mainly from both the reverse calculation method for historical cropland data based on modern spatial patterns, and modern land-use outputs from satellite data.

关键词： LUCC dataset accuracy assessment Northeast China

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LiFE:Deep Exploration via Linear-Feature Bonus in Continuous Control

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Tsinghua Science and Technology 2023年第1期28卷 155-166页

作者： Jiantao Qiu Yu Wang Department of Electronic Engineering and beijing National research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084China

Reinforcement Learning(RL)algorithms work well with well-defined rewards,but they fail with sparse/deceptive rewards and require additional exploration *** work introduces a deep exploration method based on the Upper Confidence Bound(UCB)*** proposed method can be plugged into actor-critic algorithms that use deep neural networks as a *** on the conclusion of the regret bound under the linear Markov decision process approximation,we use the feature matrix to calculate the UCB bonus for deep *** proposed method is equivalent to the count-based exploration method in special cases and is suitable for general *** method uses the last d-dimensional feature vector in the critic network and is easy to *** design a simple task,“swim”,to demonstrate the principle of the proposed method to achieve exploration in sparse/deceptive reward ***,we perform an empirical evaluation on sparse/deceptive reward version gym environments and Ackermann robot control *** evaluation results verify that the proposed algorithm can perform effective deep explorations in sparse/deceptive reward tasks.

关键词： Reinforcement Learning(RL) Neural Network(NN) Upper Confidence Bound(UCB)