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Reliability of Docking-Based Virtual Screening for GPCR Ligands with Homology Modeled Structures: A Case Study of the Angiotensin II Type I Receptor

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ACS CHEMICAL NEUROSCIENCE 2019年第1期10卷 677-689页

作者： Chen, Haiyi Fu, Weitao Wang, Zhe Wang, xuwen Lei, Tailong Zhu, feng Li, Dan Chang, Shan Xu, Lei Hou, Tingjun Zhejiang Univ Coll Pharmaceut Sci Hangzhou 310058 Zhejiang Peoples R China Zhejiang Univ State Key Lab CAD&CG Hangzhou 310058 Zhejiang Peoples R China Jiangsu Univ Technol Sch Elect & Informat Engn Inst Bioinformat & Med Engn Changzhou 213001 Peoples R China

The number of solved G-protein-coupled receptor (GPCR) crystal structures has expanded rapidly, but most GPCR structures remain unsolved. Therefore, computational techniques, such as homology modeling, have been widely used to produce the theoretical structures of various GPCRs for structure-based drug design (SBDD). Due to the low sequence similarity shared by the transmembrane domains of GPCRs, accurate prediction of GPCR structures by homology modeling is quite challenging. In this study, angiotensin II type I receptor (AT1R) was taken as a typical case to assess the reliability of class A GPCR homology models for SBDD. Four homology models of angiotensin II type I receptor (AT1R) at the inactive state were built based on the crystal structures of CXCR4 chemokine receptor, CCRS chemo-kine receptor, and delta-opioid receptor, and refined through molecular dynamics (MD) simulations and induced-fit docking, to allow for backbone and side-chain flexibility. Then, the quality of the homology models was assessed relative to the crystal structures in terms of two criteria commonly used in SBDD: prediction accuracy of ligand-binding poses and screening power of docking-based virtual screening. It was found that the crystal structures outperformed the homology models prior to any refinement in both assessments. MD simulations could generally improve the docking results for both the crystal structures and homology models. Moreover, the optimized homology model refined by MD simulations and induced-fit docking even shows a similar performance of the docking assessment to the crystal structures. Our results indicate that it is possible to establish a reliable class A GPCR homology model for SBDD through the refinement by integrating multiple molecular modeling techniques.

关键词： Docking-based virtual screening homology model class A GPCRs antagonist MD simulation induced-fit docking

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A Two-level Learning Approach for Achieving the Sustainable Development of Service Ecosystem

A Two-level Learning Approach for Achieving the Sustainable ...

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IEEE International Conference on Web Services (IEEE ICWS)

作者： Peng, Chao Xue, Xiao Zhang, xuwen Ji, Peilin Shen, Yifan Fang, Li feng, Zhiyong Tianjin Univ Coll Intelligence & Comp Tianjin Peoples R China Tianjin Key Lab Healthy Habitat & Mart Technol Tianjin Peoples R China Xian Univ Finance & Econ Sch Informat Xian Peoples R China

ISBN: (纸本)9798350368567;9798350368550

The governance of service ecosystem needs to balance efficiency and fairness to promote the sustainable development of the system, making it an important topic. However, service entities in the service ecosystem have autonomy and engage in dynamic game with governance strategies, leading to governance challenges. To address this issue, we model the governance process as a repeated sequential game between the governance algorithm and service entities, and propose a novel two-level learning algorithm. This algorithm considers the learning evolution of service entities and the co-evolutionary of the governance algorithm, using reinforcement learning to learn effective governance strategies while also considering the response function of service entities to balance efficiency and fairness. Combining the ideas of bilevel optimization and online learning, this algorithm effectively balances exploration (understanding the service entities' responses function) and exploitation (choosing efficient actions). We apply the algorithm to a classic service ecosystem, the ride-hailing service system, and empirically demonstrate its effectiveness in the governance task of order dispatching.

关键词： Service Ecosystem Governance Reinforcement Learning Balancing Efficiency and Fairness

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Altered levels of circulating CD8⁺CXCR5⁺PD-1⁺T follicular cytotoxic cells in primary Sjogren's syndrome

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CLINICAL RHEUMATOLOGY 2022年第6期41卷 1697-1708页

作者： Zhai, xuwen Wang, Yanlin Guo, Hui Liang, Zhaojun feng, Min Wu, Yanyao Qin, Yan Zhao, Xiangcong Gao, Chong Luo, Jing Shanxi Med Univ Simulat Hosp Clin Skills Teaching Jinzhong 030600 Shanxi Peoples R China Shanxi Med Univ Dept Med Div Rheumatol Hosp 2 Taiyuan 030001 Shanxi Peoples R China Shanxi Med Univ Dept Med Div Nephrol Hosp 2 Taiyuan 030001 Shanxi Peoples R China Shenzhen Baoan Shiyan Peoples Hosp Dept Med Div Nephrol Shenzhen 518005 Guangdong Peoples R China Harvard Med Sch Brigham & Womens Hosp Dept Pathol Boston MA 02115 USA

Background Circulating CD8(+)T-cells expressing the C-X-C chemokine receptor type 5 (CXCR5) (CD8(+)CXCR5(+)T), a recently identified follicular cytotoxic T cell subset, are involved in antiviral immunity and autoimmunity, but their abundance and role in the pathogenesis of primary Sjogren syndrome (pSS) are unknown. Methods Circulating CD8(+)CXCR5(+)T cell and CD8(+) regulatory T cells (CD8(+)Treg) were evaluated in 49 pSS patients (19 patients with pulmonary involvement) and 24 age- and sex-matched healthy controls (HCs) by flow cytometry. Orthogonal partial least squares discriminant analysis (OPLS-DA) was performed, and receiver operating characteristic curves (ROC) were generated to identify characteristic cell subsets. Spearman's correlation analysis was conducted to examine the relationships between CD8(+)T cell subsets and clinical features. Results The proportions and numbers of CD8(+)CXCR5(+) , CD8(+)CXCR5(+) programmed death 1-positive (PD-1(+)), and CD8(+)CXCR5 PD-1(+)T cells were significantly higher, whereas those of CD8 +/- Treg were markedly lower, in pSS patients than HCs. The CD8(+)CXCR5(+)PD-1(+)T cell to CD8(+)Treg ratio had the greatest discriminatory power for pSS and HCs according to OPLS-DA and ROC analyses. The increased numbers of CD8(+)CXCR5(+)T cells and CD8(+)CXCR5(+)PD-1(+)T cells were strongly associated with those of CD4(+)CXCR5(+)T and B cells. The proportions and numbers of CD8(+)CXCR5(+)PD-1(+)T cells were increased in pSS patients with lung involvement. Conclusions We identified a new CD8(+)CXCR5(+)PD-1(+)T subset, which was increased in abundance in pSS patients, particularly those with lung involvement, compared with HCs. Also, the CD8(+)CXCR5(+)PD-1(+)T to CD8(+)Treg ratio may be useful for identifying pSS. Our findings suggest that targeting follicular CD8(+)T cell subsets has therapeutic potential for pSS.

关键词： CD8(+)CXCR5(+) follicular cytotoxic T subsets CD8(+) regulatory T cells Lung involvement OPLS-DA Primary Sjogren's syndrome

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Deep Reinforcement Learning Home Energy Management Based Local Energy Trading in a Blockchain Platform 9

Deep Reinforcement Learning Home Energy Management Based Loc...

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9th Asia Conference on Power and Electrical Engineering, ACPEE 2024

作者： Jiang, Yu feng, Yingchun Fan, Jie Gao, Bo Wang, Yang Liu, xuwen Jiangsu Electric Power Trading Center State Grid Jiangsu Electric Power Co. LTD Nanjing China

ISBN: (纸本)9798350309638

Decentralized peer-to-peer Local Energy Markets (LEMs) are gaining popularity as local power production from Renewable Energy Sources (RESs) increases. The study investigates a blockchain-driven LEM in which prosumers and consumers buy and sell energy independently of the involvement of a third party. The suggested scheme involves Home Energy Management (HEM) and demurrage mechanisms that enable both consumers and prosumers to reduce their power prices and improve their power usage. The end-user can likewise move the load to off-peak periods and benefit from lower energy costs from the LEM through the approach. In this solution, HEM and demurrage mechanisms are used to optimize power usage as well as energy costs. As well as providing adequate power for the LEM, it is economically beneficial for end users and the community. The proposed system in the study utilizes the Deep Deterministic Policy Gradient (DDPG) algorithm and demurrage mechanisms to optimize electricity usage and energy costs. Meanwhile, smart contract on the Ethereum blockchain regulate and safeguard the electricity trading process. © 2024 IEEE.

关键词： Blockchain

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The mobility of thallium in sediments and source apportionment by lead isotopes

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CHEMOSPHERE 2019年 219卷 864-874页

作者： Liu, Juan Yin, Meiling Luo, xuwen Xiao, Tangfu Wu, Zhifeng Li, Nuo Wang, Jin Zhang, Weilong Lippold, Holger Belshaw, Nick Stanley feng, Yuexing Chen, Yongheng Guangzhou Univ Sch Environm Sci & Engn Inst Environm Res Greater Bay Minist EducKey Lab Water Qual & Conservat Pearl Guangzhou 510006 Guangdong Peoples R China Univ Oxford Dept Earth Sci Oxford OX1 3AN England Helmholtz Zentrum Dresden Rossendorf Inst Ressourcenokol D-04318 Leipzig Germany Univ Queensland Sch Earth & Environm Sci Brisbane Qld 4072 Australia

Thallium (TI) is a very toxic heavy metal. As a part of ongoing investigations, the mobility, sources and fate of TI were investigated for sediments from a watershed in the northern part of the Pearl River, South China, whose catchment has been seriously impacted by large-scale Pb Zn smelting activities onshore. A wide dispersion of severe TI contamination was observed throughout the depth profiles. A modified IRMM (Institute for Reference Materials and Measurements, Europe) sequential extraction procedure of a selected depth profile uncovered an exceptionally high enrichment of TI in geochemically-mobile fractions (i.e., weak-acid-exchangeable, reducible and oxidizable fractions), on average 5.94 +/- 2.19 mg/kg (74.6% +/- 5.1% of the total TI content) not only in the surface sediments but also in deep sediments. The proximal quantitative source apportionment using Pb isotopic fingerprinting technique indicated that a majority (80%-90%) of TI contamination along the depth profiles is anthropogenically derived from the Pb Zn smelting wastes. The results highlight the pivotal role of smelting activities in discharging huge amounts of geochemically-mobile TI to the sediments down to approximately 1 m in length, which is quantitatively evidenced by Pb isotopic tracing technique. Lead isotopes combined with distribution of TI and Pb contents identified a potential marker for a point source from the Pb Zn smelter in the river catchment, which also provides a theoretical framework for source apportionment of metal contamination in a larger river/marine system and in other sulfide mining/smelting areas likewise. (C) 2018 Elsevier Ltd. All rights reserved.

关键词： Thallium mobility Lead isotopes Source apportionnient Pb Zn smelting

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Improved Eagle Perching Optimizer Based P2P Energy Trading for Smart Homes 9

Improved Eagle Perching Optimizer Based P2P Energy Trading f...

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9th Asia Conference on Power and Electrical Engineering, ACPEE 2024

作者： Jiang, Yu feng, Yingchun Fan, Jie Gao, Bo Wang, Yang Liu, xuwen State Grid Jiangsu Electric Power Co. LTD Jiangsu Electric Power Trading Center Nanjing China

ISBN: (纸本)9798350309638

The purpose of the study is to optimize power price in smart homes that connect to share energy. A Demand Side Management (DSM) system is used to coordinate P2P energy trading between smart homes using the improved eagle perching optimizer (IEPO). The IEPO algorithm produces optimum solutions for 99% of actual datasets, according to the outcomes. It is possible that consumer price distribution in the microgrid (MG) could be unequal as a result of P2P energy trading. The Pareto optimality principle addresses the issue of unequal price distribution, preventing households from being harmed by improving the costs of others. A final evaluation is performed on the effect of renewable energy and the penetration of storage within the MG. As the renewable energy and the penetration of storage increases, savings cannot necessarily be linear. As the saturation point approaches, they slowly begin to decline. © 2024 IEEE.

关键词： Demand side management

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混合工质电动汽车空调全生命周期气候性能分析

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汽车工程 2024年第9期46卷 1707-1714页

作者：周峰田旭文李红旗北京工业大学制冷与低温工程系北京100124 传热强化与过程节能教育部重点实验室北京100124

空调作为整车系统中环境调控的关键子系统,其全生命周期的碳排放对于电动汽车的环保和排放要求至关重要。本文结合汽车空调系统全生命周期气候性能LCCP模型及相关数据,对全国各省份电动汽车空调系统的LCCP情况进行分析,同时对两种不同... 详细信息

空调作为整车系统中环境调控的关键子系统,其全生命周期的碳排放对于电动汽车的环保和排放要求至关重要。本文结合汽车空调系统全生命周期气候性能LCCP模型及相关数据,对全国各省份电动汽车空调系统的LCCP情况进行分析,同时对两种不同制热方案以及不同电力碳强度下的LCCP进行了比较分析。结果表明,RE170/R134a低GWP混合工质(二甲醚与R134a质量分数比90∶10)替换后电动汽车空调LCCP值降低了11.2%~28.1%,而采用热泵替换PTC电加热器后电动汽车空调LCCP值降低了0~33.1%,此外,随着未来我国电力碳强度与电动汽车保有量的变化,至2035年单辆车的LCCP值将会下降31.7%~39.3%,而全国整体电动汽车LCCP值将大幅上升。

关键词：低GWP混合工质全生命周期气候性能空调系统电动汽车

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Structure-Based Drug Design and Identification of H₂O-Soluble and Low Toxic Hexacyclic Camptothecin Derivatives with Improved Efficacy in Cancer and Lethal Inflammation Models in Vivo

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JOURNAL OF MEDICINAL CHEMISTRY 2018年第19期61卷 8613-8624页

作者： Pang, Peichen Chen, Jiean Li, Xijian Li, Miyang Yu, Huidong Zhao, Jean J. Ni, Jing Wang, xuwen Sun, Huiyong Tian, Sheng Zhu, feng Liu, feng Huang, Yong Hou, Tingjun Zhejiang Univ Coll Pharmaceut Sci Hangzhou 310058 Zhejiang Peoples R China Zhejiang Univ State Key Lab CAD&CG Hangzhou 310058 Zhejiang Peoples R China Peking Univ State Key Lab Chem Oncogen Key Lab Chem Genom Shenzhen Grad Sch Shenzhen 518055 Guangdong Peoples R China Rongene Pharma Co Ltd Guangzhou 510663 Guandong Peoples R China Dana Farber Canc Inst Dept Canc Biol Boston MA 02215 USA Harvard Med Sch Dept Biol Chem & Mol Pharmacol Boston MA 02215 USA Soochow Univ Coll Pharmaceut Sci Suzhou 215123 Jiangsu Peoples R China

Camptothecin (CPT) has been shown to block disassembly of the topoisomerase I (Topo I)/DNA cleavable complex. However, the poor aqueous solubility, intrinsic instability, and severe toxicity of CPTs have limited their clinical applications. Herein, we report the design and synthesis of H2O-soluble and orally bioavailable hexacyclic CPT derivatives. By analysis of a virtual chemical library and cytotoxicity screening in vitro, 9 and 11 were identified as potential prodrugs and chosen for further characterization in vivo. Both compounds exhibited remarkable anticancer and anti-inflammation efficacies in animals and improved drug-like profiles.

关键词： Mixtures Rodent models Solubility Genetics Toxicity

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Oral immunization of mice with a probiotic Lactobacillus casei constitutively expressing the α-toxoid induces protective immunity against Clostridium perfringens α-toxin

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VIRULENCE 2019年第1期10卷 166-179页

作者： Gao, xuwen Ma, Yingying Wang, Zhuo Bai, Jing Jia, Shuo feng, Baohua Jiang, Yanping Cui, Wen Tang, Lijie Li, Yijing Wang, Li Xu, Yigang Northeast Agr Univ Coll Vet Med Harbin Heilongjiang Peoples R China China Minist Agr Key Lab Anim Pathogen Biol Northeastern Sci Inspect Stn Harbin Heilongjiang Peoples R China Northeast Agr Univ Heilongjiang Key Lab Anim Dis Control & Pharmaceu Harbin Heilongjiang Peoples R China

Clostridium perfringens alpha-toxin is one of the major virulence factors during C. perfringens infection, causing hemolysis of erythrocytes in various species. Here, genetically engineered Lactobacillus casei (pPG-alpha/L. casei 393) constitutively expressing the toxoid of C. perfringens alpha-toxin was generated and its immunogenicity in mice for induction of protective immunity against the alpha-toxin was evaluated via oral immunization. The alpha-toxoid was constitutively expressed by pPG-alpha/L. casei 393 without a specific inducer, as confirmed by western blotting, laser confocal microscopy, and flow cytometry. In an experiment on BALB/c mice to evaluate the oral immunogenicity of pPG-alpha/L. casei 393, significant levels of a specific secretory IgA (sIgA) antibody in the intestinal mucus and feces and an IgG antibody in the serum of the probiotic vaccine group were detected after booster immunization (p < 0.05) as compared with the pPG/L. casei 393 and PBS control groups. These antibodies effectively neutralized C. perfringens natural alpha-toxin. Moreover, significantly higher levels of cytokines IL-2, IL-4, IL-10, IL-12, IL-17, and interferon (IFN) gamma in the serum and increased proliferation of spleen lymphocytes obtained from mice orally immunized with pPG-alpha/L. casei 393 were detected. With a commercial C. perfringens type A inactivated vaccine as a control, immune protection provided by the probiotic vaccine against C. perfringens alpha-toxin was evaluated, and 90% and 80% protection rates were observed, respectively. Therefore, strain pPG-alpha/L. casei 393 effectively elicited mucosal, humoral, and cellular immunity, suggesting that pPG-alpha/L. casei 393 is a promising candidate for development of a vaccine against C. perfringens alpha-toxin.

关键词： Clostridium perfringens alpha-toxoid genetically engineered Lactobacillus casei oral immunization

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Electromagnetic wave absorption properties of red mud-blast furnace slag based geopolymers filled with various wave-absorption materials

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CONSTRUCTION AND BUILDING MATERIALS 2023年 404卷

作者： Wang, Tianyu Ning, xuwen Yang, Lang Rao, feng Jiang, Kaixi Fuzhou Univ Sch Mat Sci & Engn Fuzhou 350108 Fujian Peoples R China Fuzhou Univ Zijin Sch Geol & Min Fuzhou 350108 Fujian Peoples R China Fuzhou Univ Fujian Key Lab Green Extract & High value Utilizat Fuzhou 350108 Fujian Peoples R China

In this work, red mud-blast furnace slag (RM-BFS) based geopolymers with excellent electromagnetic wave absorption property is synthesized through the incorporation of wave-absorption materials. The electromagnetic absorption property of geopolymer is characterized through the arched test, in which the reflection loss of specimens is tested by vector network analyzer (VNA). The microstructure and conductivity of geopolymers are characterized through scanning electron microscopy (SEM), concrete porous structure analyzer and conductivity tester. The crystalline phase and functional groups of geopolymers are characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Compared to Portland cement concrete (PCC), wave absorption band of the geopolymer is wider and the absorption peak in high frequency band is more intense. With the optimal addition of hollow glass microsphere (HGM), Fe2O3 and graphite particles, the absorption bandwidth with reflection loss less than -5 dB are 12.4, 7.7 and 8.1 GHz, and the maximum reflection loss are -9.4, -8.4 and -8.7 dB, respectively. This study might give a clue for preparation of geopolymers with high electromagnetic wave absorption properties.

关键词： Electromagnetic wave Compressive strength Microstructure Geopolymers Conductivity

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