检索结果-南通市图书馆

Reaction Mechanism of Actin ATP Hydrolysis Studied by QM/MM Calculations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2024年第5期40卷 849-855页

作者： wang Yiwen liN lirui XU li-yan li En-Min DONG geng Department of Biochemistry and Molecular Biology Shantou University Medical CollegeShantou515041P.R.China Department of Bioinformatics Shantou University Medical CollegeShantou515041P.R.China Medical Informatics Research Center Shantou University Medical CollegeShantou515041P.R.China Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Area of Guangdong Higher Education Institutes Shantou University Medical CollegeShantou515041P.R.China Cancer Research Center Shantou University Medical CollegeShantou515041P.R.China Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology Shantou University Medical CollegeShantou515041P.R.China

Actin fibers are an important part of the cytoskeleton,providing vital support for the plasma *** function is driven by its ATPase(ATP:adenosine triphosphate)activity,i.e.,ATP+H_(2)O→ADP+*** seemingly simple reaction has attracted much attention because the hydrolysis of ATP provides energy to support life ***,the reaction mechanism of ATP hydrolysis in actin is not *** order to gain deep insights into the functions of actin,it is essential to elucidate the reaction mechanism of the actin ATP *** this paper,we have studied the reaction mechanism of the ATP hydrolysis in actin by the combined quantum mechanical and molecular mechanics(QM/MM)*** results show that 1)bond cleavage of the Pγ—OS of ATP and bond formation between oxygen of the lytic water and Pγatoms take place simultaneously,and this is the rate-limiting step of the hydrolysis;2)the proton on the lytic water transfers to the phosphate to form H_(2)P_(γ)O_(4)−via one bridge *** energy barrier of the complete reaction is 17.6 kcal/mol(1 kcal=4.184 kJ),which is in high agreement with the experimental value.

关键词： Actin Adenosine triphosphate(ATP)hydrolysis Quantum mechanical and molecular mechanics(QM/MM) Reaction mechanism

Standardized Volume Power Density Boost in Frequency-Up Converted Contact-Separation Mode Triboelectric Nanogenerators

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research 2024年第2期2023卷 691-702页

作者： Zhongjie li Chao yang Qin Zhang geng Chen Jingyuan Xu yan Peng Hengyu Guo School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444P.R.China Institute of Artificial Intelligence Shanghai UniversityShanghai 200444P.R.China National Engineering Research Center of Turbo-Generator Vibration School of Energy and EnvironmentSoutheast UniversityNanjing 210096P.R.China institute of Microstructure Technology Karlsruhe Institute of TechnologyKarlsruhe 76344Germany Shanghai Artificial Intelligence Laboratory Shanghai 200444P.R.China Department of Applied Physics Chongqing UniversityChongqing 400044P.R.China

The influence of a mechanical structure's volume increment on the volume power density (VPD) of triboelectric nanogenerators (TENGs) is often neglected when considering surface charge density and surface power density. This paper aims to address this gap by introducing a standardized VPD metric for a more comprehensive evaluation of TENG performance. The study specifically focuses on 2 frequency-up mechanisms, namely, the integration of planetary gears (PG-TENG) and the implementation of a double-cantilever structure (DC-TENG), to investigate their impact on VPD. The study reveals that the PG-TENG achieves the highest volume average power density, measuring at 0.92 W/m^(3). This value surpasses the DC-TENG by 1.26 times and the counterpart TENG by a magnitude of 69.9 times. Additionally, the PG-TENG demonstrates superior average power output. These findings introduce a new approach for enhancing TENGs by incorporating frequency-up mechanisms, and highlight the importance of VPD as a key performance metric for evaluating TENGs.

关键词： increment neglected considering

Intelligent overheating fault diagnosis for overhead transmission line using semantic segmentation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Voltage 2024年第2期9卷 309-318页

作者： Xiangyu yang Youping Tu zhikang Yuan Zhong Zheng geng Chen Cong wang yan Xu Beijing Key Laboratory of High Voltage and EMC North China Electric Power UniversityBeijingChina College of Electronic and Information Engineering Tongji UniversityShanghaiChina

The strain clamps and leading wires are important components that connect conductors on overhead transmission lines and conduct *** operation,poor contact between these components can cause abnormal overheating,leading to electric failures and threatening power system ***,the use of unmanned aerial vehicles equipped with infrared thermal imagers for strain clamp and leading wire maintenance has become increasingly *** learning-based image recognition shows promising prospects for intelligent fault diagnosis of overheating faults.A pre-treatment method is proposed based on dynamic histogram equalisation to enhance the contrast of infrared *** DeepLab v3+network,loss function,and existing networks with different backbones are *** DeepLab v3+network with ResNet101 and convolutional block attention module added,and the Focal Loss function achieved the highest performance with an average pixel accuracy of 0.614,an average intersection over union(AIoU)of 0.567,an F1 score of 0.644,and a frequency weighted intersection over union of 0.594 on the test *** optimised Atrous rates has increased the AIoU by 12.91%.Moreover,an intelligent diagnosis scheme for evaluating the defect state of the strain clamps and leading wires is proposed and which achieves a diagnostic accuracy of 91.0%.

关键词： union fault diagnosis

Artemsieverolactones A—H,Eight Guaiane-Type Sesquiterpenoid Trimers from Artemisia sieversiana

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第10期42卷 1084-1092页

作者： Wei Dong Xiao-yan Huang Tian-Ze li yan-Mei Weng Chang-An geng Ji-Jun Chen State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academyof Sciences Beijing 100049China

Eight new guaiane-type sesquiterpenoid trimers,artemsieverolactones A—H,possessing unprecedented scaffolds via biocatalyzed[4+2]Diels−Alder cycloaddition reactions were identified from Artemisia *** structures were determined by comprehensive spectroscopic data,single-crystal X-ray diffraction analyses,and ECD *** terms of structure,artemsieverolactones A—H are first examples of sesquiterpenoid trimers from guaiane-type sesquiterpenoid through four different[4+2]Diels−Alder cycloaddition *** fibrosis assay suggested that five compounds exhibited activity against HSC-LX2 with IC_(50)values ranging from 37.8 to 117.1μmol/*** most active artemsieverolactone B(2)displayed significant inhibitory activity against HSC-LX2 with IC_(50)value of 37.8μmol/L,which was 3 times more active than the positive drug silybin(IC_(50),139.7μmol/L).Preliminary mechanism study revealed that artemsieverolactone B could inhibit the deposition of human collagen typeⅠ(ColⅠ),human hyaluronic acid(HA),and human laminin(HL)with IC_(50)values of 40.4μmol/L(Col I),55.1μmol/L(HL),47.3μmol/L(HA),which was 2 to 3-fold more potent than silybin.

关键词： Artemisia sieversiana Artemsieverolactones A-H Guaiane-type sesquiterpenoid trimers Antihepatic fibrosis Extracellular matrix Cancer NMR spectroscopy X-ray diffraction

Relationship between the unique microstructures and behaviors of high-entropy alloys

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1350-1363页

作者： Yaqi Wu Peter Kliaw Ruixuan li Weiran Zhang Guihong geng Xuehui yan Guiqun liu Yong Zhang State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN 37996USA Xi’an Rare Metal Materials Institute Co.Ltd. Xi’an 710016China School of Materials Science and Engineering North Minzu UniversityYinchuan 750030China GRIMAT Engineering Institute Co. Ltd.Beijing 101407China

High-entropy alloys(HEAs),which were introduced as a pioneering concept in 2004,have captured the keen interest of nu-merous ***,in this context,can be perceived as representing disorder and *** contrast,elemental composi-tions within alloy systems occupy specific structural sites in space,a concept referred to as *** accordance with Shannon entropy,structure is analogous to ***,the arrangement of atoms within a material,termed its structure,plays a pivotal role in dictating its *** addition to expanding the array of options for alloy composites,HEAs afford ample opportunities for diverse structural *** profound influence of distinct structural features on the exceptional behaviors of alloys is underscored by numer-ous *** features include remarkably high fracture strength with excellent ductility,antiballistic capability,exceptional radi-ation resistance,and corrosion *** this paper,we delve into various unique material structures and properties while elucidating the intricate relationship between structure and performance.

关键词： high-entropy alloys unique microstructure special properties alloy design

PIM1-HDAC2 axis modulates intestinal homeostasis through epigenetic modification

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2024年第7期14卷 3049-3067页

作者： Jianming yang Yawen Xiao Ningning Zhao geng Pei yan Sun Xinyu Sun Kaiyuan Yu Chunhui Miao Ran liu Junqiang Lv Hongyu Chu Lu Zhou Bangmao wang zhi Yao Quan wang Key Laboratory of Immune Microenvironment and Disease(Ministry of Education) Tianjin Institute of ImmunologyState Key Laboratory of Experimental Hematologythe Province and Ministry Co-sponsored Collaborative Innovation Center for Medical EpigeneticsDepartment of ImmunologySchool of Basic Medical SciencesTianjin Institute of Urologythe Second Hospital of Tianjin Medical UniversityTianjin Key Laboratory of Cellular and Molecular ImmunologyTianjin Medical UniversityTianjin 300070China Department of Pathology Tianjin Medical University Cancer Institute and Hospital/National Clinical Research Center of Cancer/Key Laboratory of Cancer Prevention and TherapyTianjin/Tianjin’s Clinical Research Center of CancerTianjin 30060China Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalTianjin Medical UniversityTianjin 300070China

The mucosal barrier is crucial for intestinal homeostasis,and goblet cells are essential for maintaining the mucosal barrier *** proviral integration site for Moloney murine leukemia virus-1(PIM1)kinase regulates multiple cellular functions,but its role in intestinal homeostasis during colitis is ***,we demonstrate that PIM1 is prominently elevated in the colonic epithelia of both ulcerative colitis patients and murine models,in the presence of intestinal *** PIM1 leads to decreased goblet cells,thus impairing resistance to colitis and colitis-associated colorectal cancer(CAC)in ***,PIM1 modulates goblet cell differentiation through the Wnt and Notch signaling ***,PIM1 interacts with histone deacetylase 2(HDAC2)and downregulates its level via phosphorylation,thereby altering the epigenetic profiles of Wnt signaling pathway ***,these findings investigate the unknown function of the PIM1-HDAC2 axis in goblet cell differentiation and ulcerative colitis/CAC pathogenesis,which points to the potential for PIM1-targeted therapies of ulcerative colitis and CAC.

关键词： PIM1 HDAC2 Goblet cell Gut microbiota Intestinal homeostasis Epigenetic modification Ulcerative colitis CAC

CPT: a pre-trained unbalanced transformer for both Chinese language understanding and generation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第5期67卷 43-55页

作者： Yunfan SHAO zhichao geng Yitao liU Junqi DAI Hang yan Fei yanG Zhe li Hujun BAO Xipeng QIU School of Computer Science Fudan University Shanghai Key Laboratory of Intelligent Information Processing Fudan University Zhejiang Lab

In this paper, we take the advantage of previous pre-trained models(PTMs) and propose a novel Chinese pre-trained unbalanced transformer(CPT). Different from previous Chinese PTMs, CPT is designed to utilize the shared knowledge between natural language understanding(NLU) and natural language generation(NLG) to boost the performance. CPT consists of three parts: a shared encoder, an understanding decoder, and a generation decoder. Two specific decoders with a shared encoder are pretrained with masked language modeling(MLM) and denoising auto-encoding(DAE) tasks, *** the partially shared architecture and multi-task pre-training, CPT can(1) learn specific knowledge of both NLU or NLG tasks with two decoders and(2) be fine-tuned flexibly that fully exploits the potential of the model. Moreover, the unbalanced transformer saves the computational and storage cost, which makes CPT competitive and greatly accelerates the inference of text generation. Experimental results on a wide range of Chinese NLU and NLG tasks show the effectiveness of CPT.

关键词： pre-trained model transformer language model generation unified model

Structural insights into AtABCG25,an angiosperm-specific abscisic acid exporter

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Plant Communications 2024年第1期5卷 284-295页

作者： Jian Xin Yeling Zhou Yichun Qiu He geng Yuzhu wang Yi Song Jiansheng liang Kaige yan Department of Chemical Biology School of Life SciencesSouthern University of Science and TechnologyShenzhen 518055China Institute of Plant and Food Science Department of BiologySchool of Life SciencesSouthern University of Science and TechnologyShenzhen 518055China Max Planck Institute of Molecular Plant Physiology Potsdam-GolmGermany Institute for Biological Electron Microscopy Southern University of Science and TechnologyShenzhenGuangdongChina

Cellular hormone homeostasis is essential for precise spatial and temporal signaling responses and *** acid(ABA)plays pivotal roles in orchestrating various developmental and stress re-sponses and confersfitness benefits over ecological and evolutionary timescales in terrestrial *** ABA level is regulated by complex processes,including biosynthesis,catabolism,and ***25 is thefirst ABA exporter identified through genetic screening and affects diverse ABA *** the structural basis of ABA export by ABCG25 is critical for further manipulations of ABA homeostasis and *** used cryo-electron microscopy to elucidate the structural dynamics of AtABCG25 and successfully characterized different states,including apo AtABCG25,ABA-bound AtABCG25,and ATP-bound AtABCG25(E232Q).Notably,AtABCG25 forms a homodimer that fea-tures a deep,slit-like cavity in the transmembrane domain,and we precisely characterized the critical residues in the cavity where ABA *** binding triggers closure of the nucleotide-binding domains and conformational transitions in the transmembrane *** show that AtABCG25 belongs to a conserved ABCG subfamily that originated during the evolution of *** subfamily neofunctionalized to regulate seed germination via the endosperm,in concert with the evolution of this angio-sperm-specific,embryo-nourishing ***,thesefindings provide valuable insights into the intricate substrate recognition and transport mechanisms of the ABA exporter AtABCG25,paving the way for genetic manipulation of ABA homeostasis and plantfitness.

关键词： AtABCG25 abscisic acid ABC transporters cryo-EM structure

Direct detection of C9orf72 hexanucleotide repeat expansions by nanopore biosensor

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第5期35卷 351-354页

作者： Xinqiong li Guocheng Rao Xi Peng Chan yang yanjing Zhang yan Tian Xianghui Fu Jia geng State Key Laboratory of Biotherapy and Cancer Center West China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengdu 610041China Division of Endocrinology and Metabolism West China School of Medicine/West China HospitalSichuan UniversityChengdu 610041China Department of Endocrinology and Metabolism Affiliated Hospital of North Sichuan Medical CollegeNorth Sichuan Medical CollegeNanchong 637000China Division of Endocrinology and Metabolism National Clinical Research Center for GeriatricsState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengdu 610041China Department of Laboratory Medicine State Key Laboratory of BiotherapyMed-X Center for ManufacturingWest China HospitalSichuan University and Collaborative Innovation CenterChengdu 610041China Tianfu Jincheng Laboratory City of Future MedicineChengdu 641400China

Diagnostic C9orf72 hexanucleotide repeat expansions(C9-HRE)is essential for the early and accurate diagnosis of amyotrophic lateral sclerosis(ALS)and will provide support for the prognosis and gene therapy of *** the present study,by combining catalytic hairpin assembly(CHA)with Mycobacterium smegmatis porin A(MspA)nanopore,a new nanopore-based strategy for the detection of C9-HRE was *** than 30 repeats of C9-HRE could be detected via this method,and the results have the potential to help distinguish between patients and healthy ***,the method demonstrated its great specificity for C9-HRE by identifying other repeat *** the high selectivity,this approach had been successfully used to detect C9-HRE in cell and blood samples with high *** detection strategy is user-friendly and has a strong anti-interference ability,thus providing a powerful tool for clinical diagnosis.

关键词： MspA nanopore C9orf72 HRE Detection Biosensor Catalytic hairpin assembly