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Bacterial diversity in the sediment of Crescent Moon Spring,Kumtag Desert,Northwest China

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Journal of Arid Land 2017年第2期9卷 278-286页

作者： zhang Wei zhang Gaosen WU Xiukun LIU Guangxiu DONG Zhibao QU Jianjun WANG Yun CHEN tuo Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Gansu Key Laboratory of Extreme Environmental Microbial Resources and Engineering Lanzhou 730000China Dunhuang Gobi and Desert Ecology and Environment Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesDunhuang 736200China

Desert lake, a unique oasis in desert ecosystems, harbours different bacterial communities. Thus, it is considered as a hub of bacterial diversity. In this study, bacterial diversity in the sediment of Crescent Moon Spring, Kumtag Desert, Northwest China was analyzed using high-throughput amplicon pyrosequencing analysis. The sequences of the most abundant OUTs （Operational Taxonomic Units） in the sediment of Crescent Moon Spring were compared with the sequences of those most abundant OUTs of various origins from NCBI GenBank database to detect the origins of bacteria in the sediment of Crescent Moon Spring. Also, bacterial compositions between sediment of Crescent Moon Spring and other desert and lake ecosystems （including desert lakes） worldwide were compared using cluster analysis to determine the possible factors affecting bacterial compositions. In total, 11,855 sequences were obtained and 30 phyla were identified. At the phylum level, the dominant phylum was Proteobacteria with α-Proteobacteria being the first dominant class and the second dominant phylum was Planctomycetes. Our finding that α-Proteobacteria being the first dominant class of Proteobacteria and Planctomycetes being the second dominant phyla are somewhat contradictory with reports from other desert lake sediments. This difference could be resulted from water hydration and conductivity, as well as oligotrophic conditions of Crescent Moon Spring. At the genus level, Rhodobacter, Caldilinea, Planctomyces, and Porphyrobacterwere the dominant genera in the sediment of Crescent Moon Spring. Comparisons on sequences of the most abundant OUTs （including OTU3615, OTU6535, and OTU6646） between sediment of Crescent Moon Spring and various origins from NCBI GenBank database indicate that the origins of bacteria in the sediment of Crescent Moon Spring are likely from the underground water. Furthermore, cluster analysis on comparisons of bacteria compositions between sediment of Crescent Moon Spring and other

关键词： bacterial diversity pyrosequencing analysis desert lake desert and lake ecosystems Crescent Moon Spring

Therapeutic strategies for the costimulatory molecule OX40 in T-cell-mediated immunity

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Acta Pharmaceutica Sinica B 2020年第3期10卷 414-433页

作者： Yu Fu qing Lin Zhirong zhang Ling zhang Key Laboratory of Drug Targeting and Drug Delivery System of the Education Ministry Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyCollege of Polymer Science and EngineeringWest China School of PharmacySichuan UniversityChengdu 610064China Department of Pharmacology Yale University School of MedicineNew HavenCT 06510USA

The T cell co-stimulatory molecule OX40 and its cognate ligand OX40 L have attracted broad research interest as a therapeutic target in T cell-mediated *** preclinical evidence highlights the therapeutic efficacy of both agonist and blockade of the OX40-OX40 L *** this progress,many questions about the immuno-modulator roles of OX40 on T cell function remain *** this review we summarize the impact of the OX40-OX40 L interaction on T cell subsets,including Th1,Th2,Th9,Th17,Th22,Treg,Tfh,and CD8+T cells,to gain a comprehensive understanding of anti-OX40 mAb-based *** potential therapeutic application of the OX40-OX40 L interaction in autoimmunity diseases and cancer immunotherapy are further discussed;OX40-OX40 L blockade may ameliorate autoantigen-specific T cell responses and reduce immune activity in autoimmunity *** also explore the rationale of targeting OX40-OX40 L interactions in cancer *** of OX40 with targeted agonist anti-OX40 mAbs conveys activating signals to T *** combined with other therapeutic treatments,such as anti-PD-1 or anti-CTLA-4 blockade,cytokines,chemotherapy,or radiotherapy,the anti-tumor activity of agonist anti-OX40 treatment will be further *** data collectively suggest great potential for OX40-mediated therapies.

关键词： OX40 CD4^+ CD8^+ Treg Autoimmunity diseases Cancer immunotherapy

Misdiagnosis of hemangioma of left triangular ligament of the liver as gastric submucosal stromal tumor:Two case reports

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2351-2357页

作者： Jing-Jie Wang Fen-Ming zhang Wei Chen Hua-tuo Zhu Ning-Long Gui Ai-qing Li Hong-Tan Chen Department of Gastroenterology The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina

BACKGROUND Extragastric lesions are typically not misdiagnosed as gastric submucosal tumor(SMT).However,we encountered two rare cases where extrinsic lesions were misdiagnosed as gastric *** SUMMARY We describe two cases of gastric SMT-like protrusions initially misdiagnosed as gastric SMTs by the abdominal contrast-enhanced computed tomography(CT)and endoscopic ultrasound(EUS).Based on the CT and EUS findings,the patients underwent gastroscopy;however,no tumor was identified after incising the gastric *** surgical exploration revealed no gastric lesions in both patients,but a mass was found in the left triangular ligament of the *** patients underwent laparoscopic tumor resection,and the postoperative diagnosis was hepatic *** During EUS procedures,scanning across different layers and at varying degrees of gastric cavity distension,coupled with meticulous image analysis,has the potential to mitigate the likelihood of such misdiagnoses.

关键词： Submucosal tumor Extragastric compression Endoscopic ultrasonography Computed tomography Hemangioma of the left triangular ligament of the liver Case report

Crystal structures and hydrogenation behavior of (Ca_(0.9)Sr_(0.1))_8(Al_(1-x)Zn_x)_3 alloys

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Rare Metals 2008年第2期27卷 134-137页

作者： SI Tingzhi YANG Weiming zhang qing＇an School of Materials Science and Engineering Anhui University of Technology Maanshan 243002 China

The crystal structures and hydrogenation behavior of the （Ca0.9Sr0.1）8（Al1-xZnx）3 （x = 0, 0.1, 0.2, 0.3 and 0.4） alloys were investigated. The new phase （Ca,Sr）E（Al,Zn） was found whenx 〉 0.1. （Ca, Sr）E（Al,Zn） crystallizes in space group 14/mmm （A-139）. The lattice parameters were calculated to be a = b = 1.1616（2） nm, c = 1.6422（4） nm. Zn atoms occupy the 8h and 16n sites together with Al atoms. The （Ca0.9Sr0.1）8Al3 alloy only contains a single Ca8Al3 phase. The （Ca0.9Sr0.1）8（Al1-xZnx）3 alloys consist of Ca8Al3, CasZn3, Ca and （Ca,Sr）2（Al,Zn） phases when x is from 0.1 to 0.3. As x increasing to 0.4, the alloy consists of （Ca,Sr）E（Al,Zn）, Ca8Zn3 and Ca. The hydrogenated （Ca0.9Sr0.1）8Al3 and （Ca0.9Sr0.1）8（Al0.9Zn0.1）3 samples consist of CartE and Al. The （Ca0.9Sr0.1）8（Al1-xZnx）3 （x = 0.2, 0.3 and 0.4） samples can be hydrogenated into CaH2, Al and CaZnl3 under a hydrogen pressure of 5 MPa at 473 K.

关键词： calcium-based alloys crystal structure X-ray diffraction hydrogenation behavior.

Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

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Petroleum Science 2024年第3期21卷 2048-2065页

作者： qing-Ping Li Jin-Ya zhang Jia-Xiang zhang Yong-Xue zhang CNOOC Research Institute Company Limited Beijing100028China State Key Laboratory of Natural Gas Hydrate Beijing100028China College of Mechanical and Transportation Engineering China University of PetroleumBeijing2249China

Slug flow or high GVF(Gas Volume Fraction)conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps,endangering the safety of multiphase pump *** mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation ***(User Define Function)programs such as structural dynamics equations,alternating load equations,and pressure disturbance equations are embedded in numerical calculations,and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh *** results show that when the pressure disturbance occurs at the inlet,as the amplitude and period of the disturbance increase,the film thickness gradually *** the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely *** maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance *** mutual interference between enhanced waves does not have a significant impact on the film thickness,while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes,and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial *** with pressure disturbance conditions,alternating load conditions have a more significant impact on film thickness and *** actual operation,it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

关键词： Multiphase pump Liquid film seal Pressure disturbance wave Dynamic response characteristics

Cryptanalysis and Improvement of a Quantum Secret Sharing Protocol between Multiparty and Multiparty with Single Photons and Unitary Transformations

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Chinese Physics Letters 2010年第6期27卷 13-15页

作者： ZHU Zhen-Chao zhang Yu-qing Key Lab of Computer Networks and Information Security of Ministry of Education Xidian University Xi'an 710071 National Computer Network Intrusion Protection Center Graduate University Chinese Academy of Sciences Beijing 100049

In a recent paper [Chin. Phys. Lett 25（2008）1187], a quantum secret sharing scheme between multiparty and multiparty was presented. We show that the protocol is not secure because the last member in Alice＇s group can illegally obtain most secret messages without introducing any error. Finally, a possible way to avoid the security flaw is suggested.

关键词： CRYPTOGRAPHY QUANTUM communication UNITARY transformations ERROR analysis (Mathematics) SECURITY systems

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智能网联汽车的车载网络攻防技术研究进展

软件学报 2025年第1期36卷 341-370页

作者：陈博言沈晴霓张晓磊张鑫李聪吴中海北京大学软件与微电子学院软件工程国家工程研究中心(北京大学) 高可信软件技术教育部重点实验室(北京大学) 北京大学计算机学院

随着人工智能和5G技术在汽车行业的应用,智能网联汽车应运而生,它是一种由众多来自不同供应商的电子控制单元(ECU)组成的复杂分布式异构系统,通过以CAN为代表的车载网络协议交互协同控制各ECU.然而,攻击者可能通过各种接口攻击智能网联... 详细信息

随着人工智能和5G技术在汽车行业的应用,智能网联汽车应运而生,它是一种由众多来自不同供应商的电子控制单元(ECU)组成的复杂分布式异构系统,通过以CAN为代表的车载网络协议交互协同控制各ECU.然而,攻击者可能通过各种接口攻击智能网联汽车,渗透到车载网络,再攻击车载网络及其各组成部分如ECU.因此,智能网联汽车的车载网络安全成为近些年车辆安全研究的焦点之一.在介绍智能网联汽车整体结构、ECU、CAN总线和车载诊断协议等基础之上,首先总结了目前车载网络协议的逆向工程技术进展,逆向工程的目标是获取汽车行业通常不公开的车载网络协议实现细节,也是实施攻击和防御的前提条件.然后从车载网络攻、防两个角度展开:一方面概括了车载网络攻击向量及主要攻击技术,包括通过物理访问和远程访问方式实施的攻击技术,以及针对ECU和CAN总线实施的攻击技术;另一方面,讨论了车载网络现有的防御技术,包括基于特征工程和机器学习方法的车载网络入侵检测和基于密码学方法的车载网络协议安全增强技术.最后展望了未来的研究方向.

关键词：智能网联汽车车载网络逆向工程入侵检测协议安全增强

Ultra-small Co/CoO_(x) nanoparticles dispersed on N-doped carbon nanosheets for highly efficient electrocatalytic oxygen evolution reaction

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Journal of Energy Chemistry 2021年第4期30卷 345-354页

作者： Chen Chen Zhuojun Yang Wei Liang Hao Yan Yongxiao tuo Yanpeng Li Yan Zhou Jun zhang College of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina College of Chemical Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina

In this paper,we report a facile strategy to synthesize Co-BDC-NH2 material,which is used as a precursor towards an excellent OER electrocatalyst by thermal annealing in ***-small Co/Co Oxnanoparticles were uniformly dispersed on the rhombus N-doped carbon(NC)*** electron microscopic,X-ray diffraction spectrometric,and X-ray photoelectron spectroscopic analyses revealed the coexistence of metallic Co and Co oxides *** was found that Co/CoO_(x)@NC obtained at 500℃ annealing temperature exhibited the highest electrocatalytic OER activity,with 307 and375 m V overpotential to achieve 10 and 100 m A cm^(-2) current ***,thanks to the in-situ annealing process,Co/CoO_(x)@NC showed excellent catalytic stability with 97.4%current density retention after 24 h electrolysis at 1.66 V *** electrode *** investigations revealed that the ultrasmall Co/Co Oxnanoparticles distributed on N-doped carbon template contribute significantly towards OER electrocatalysis through enlarging the activity surface areas and enhancing the intrinsic electrochemical activity due to the presence of metallic Co.

关键词： Co/CoO_(x)nanoparticle Metal-organic framework In-situ annealing Nitrogen-doped porous carbon Oxygen evolution reaction Electrocatalysis

Fractal Characteristics and Prediction of Ti-15-3 Alloy Recrystallized Microstructure

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Journal of Materials Science & Technology 2008年第6期24卷 835-839页

作者： Ping LI qing zhang Kemin XUE chool of Materials Science and Engineering Hefei University of Technology Hefei 230009 China Anhui Vocational and Technical College Hefei 230051 China

Grain shape of the hot deforming alloy is an important of material. The fractal theory was applied to analyze index to character the microstructure and performance the recrystallized microstructure of Ti-15-3 alloy after hot deformation and solution treatment. The fractal dimensions of recrystallized grains were calculated by slit island method. The influence of processing parameters on fractal dimension and grain size was studied, It has been shown that the shapes of recrystallized grain boundaries are self-similar, and the fractal dimension varies from 1 to 2. With increasing deformation degree and strain rate or decreasing deformation temperature, the fractal dimension of grain boundaries increased and the grain size decreased. So the fractal dimension could characterize the grain shape and size. A neural network model was trained to predict the fractal dimension of recrystallized microstructure and the result is in excellent agreement with the experimental data.

关键词： Ti-15-3 alloy Hot deformation Recrystallized microstructure Fractal Neural network