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Chinese Journal of Chemistry 2018年第8期36卷 708-711页

作者： youwen Sun Guozhu zhang State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Center for Excellence in Molecular Synthesis University of Chinese Academy of Sciences Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China

We report a palladium-catalyzed formal intermolecular [4＋2] cycloaddition of benzoic and acrylic acids with 1,3-dienes including the stock chemicals 1,3-butadiene and isoprene leading to synthetically useful 3,4-dihydroisocoumarins and 5,6-dihydrocoumalins. Stepwise C-H bond cleavage and annulation are likely involved in the reaction pathway. The synthetic potential of the methodology was demonstrated by two short derivatizations and total synthesis of natural product Clausamine B.

关键词： palladium（ll） C-H bond activation 1,3-diene cycloaddition natural product

A Block Parallel l_0-Norm Penalized Shrinkage and Widely Linear Affine Projection Algorithm for Adaptive Filter

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China Communications 2017年第1期14卷 86-97页

作者： Youwen Zhang Shuang Xiao Lu Liu Dajun Sun Acoustic Science and Technology Laboratory Harbin Engineering University Harbin 150001 China College of Underwater Acoustic Engineering Harbin Engineering University Harbin 150001 China

To improve the identification capability of AP algorithm in time-varying sparse system, we propose a block parallel l_0-SWL-DCD-AP algorithm in this paper. In the proposed algorithm, we first introduce the l_0-norm constraint to promote its application for sparse system. Second, we use the shrinkage denoising method to improve its track ability. Third, we adopt the widely linear processing to take advantage of the non-circular properties of communication signals. Last, to reduce the high computational complexity and make it easy to implemented, we utilize the dichotomous coordinate descent(DCD) iterations and the parallel processing to deal with the tapweight update in the proposed algorithm. To verify the convergence condition of the proposed algorithm, we also analyze its steadystate behavior. Several simulation are done and results show that the proposed algorithm can achieve a faster convergence speed and a lower steady-state misalignment than similar APA-type algorithm. When apply the proposed algorithm in the decision feedback equalizer(DFE), the bite error rate(BER) decreases obviously.

关键词： signal processing adaptive algorithm LMS l0-norm shrinkage linear DCD

MOF-5@Ni衍生的ZnO@Ni_(3)ZnC_(0.7)/PMS体系用于有机物去除——对吸附降解过程的深入理解

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Engineering 2023年第5期24卷 253-263,I0007页

作者： youwen Shuai Xue Huang Benyin zhang Lu Xiang Hao Xu Qian Ye Jinfeng Lu Jing zhang College of Architecture and Environment Sichuan UniversityChengdu 610065China College of Environmental Science and Engineering Nankai UniversityTianjin 300071China

基于过一硫酸盐的非均相催化活化技术在废水处理中越来越受到关注。因此,找到一种可持续、经济、有效的活性材料用于废水处理非常重要。本研究以金属有机框架材料(MOF)-5为前驱体,通过添加镍离子并随后煅烧制备了一种稳定、可循环利用... 详细信息

基于过一硫酸盐的非均相催化活化技术在废水处理中越来越受到关注。因此,找到一种可持续、经济、有效的活性材料用于废水处理非常重要。本研究以金属有机框架材料(MOF)-5为前驱体,通过添加镍离子并随后煅烧制备了一种稳定、可循环利用的材料ZnO@Ni_(3)ZnC_(0.7),该材料表现出良好的吸附和催化性能。为了研究和优化实际应用条件,选择了罗丹明B(RhB)在水中的降解作为模型过程。研究表明,体系中有机物的去除涉及吸附和降解过程的耦合。基于此,提出了整个去除过程的机理。扫描电子显微镜、红外光谱分析和理论分析的结果证实,范德华力、静电吸引力和氢键影响吸附过程。电子顺磁共振分析、遮蔽实验和电化学测试证实,RhB的降解路径包括自由基和非自由基途径,表面羟基是关键的活性位点。对吸附底物的降解使活性位点得到再生。用简单方法再生的材料在四个循环测试中对有机化合物的去除效率保持很高。此外,这种材料还可以有效地去除各种有机污染物,并且由于具有磁性,材料易于回收。结果表明,使用具有良好吸附能力的非均相催化材料可能是一种经济有效的策略。

关键词：废水处理降解路径去除过程非均相催化活性材料金属有机框架材料可循环利用范德华力

Structural Relief System Construction in China Based on the Experience of the USA

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学术界 2014年第5期 254-258页

作者： Liu Fuhua zhang youwen School of Public Finance and Economics Yunnan University of Finance and Economics

The USA has already established the perfect structural relief system framework with perfect related research and legislative and judicial practice. Compared with the USA,the structural relief system is far from perfection on the legislative level and the judicial level.With the implementing of Centralized Examination Methods for Operators and Temporary Provisions of Concentrated Assets and Business Stripping of Operators,the structural relief system in China has been preliminarily established. However,from the technical level,microcosmic element pillar system related to stripping system has not been established yet. According to the experience in law enforcement in the USA,China shall also formulate Handbook on Implementing Relief System in the Antitrust Scrutiny of Operators to provide helpful guide for the structural relief system in China.

关键词：结构美国中国救济制度建设剥离系统运营商层面

Multipath matching pursuit using a cross-validation technique for sparse direction-of-arrival estimation with an acoustic vector array

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Chinese Journal of Acoustics 2023年第2期42卷 153-170页

作者： TAN Peng HU Bo zhang youwen WU Yuquan YANG Desen Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001 Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001 School of Electronics and Information Jiangsu University of Science and TechnologyZhenjiang 212100 Science and Technology on Integrated Information System Laboratory Institute of SoftwareChinese Academy of SciencesBeijing 100190

High-resolution direction-of-arrival(DOA)estimations and the starboard ambiguity of moving underwater targets have always been key issues in underwater acoustic array signal processing.Compared with sound pressure arrays,vector arrays have natural advantages with respect to solving the starboard ambiguity problem and obtaining higher processing gains.Traditional high-resolution DOA estimation methods such as Capon have disadvantages such as being unable to resolve coherent sources,requiring multiple snapshot processing,and being sensitive to array manifold errors.High-resolution DOA estimation and the starboard ambiguity of moving underwater targets have always been challenging research topics.On one hand,maneuvering underwater targets reduce the coherence time of the received signals,which ultimately leads to poor performance when using high-resolution DOA estimation technologies based on the covariance matrix of the received signal.On the other hand,traditional DOA estimation technologies based on sound pressure arrays have the problem of port and starboard ambiguity,which can be solved by maneuvering the sonar platform.However,maneuvering the sonar platform can impair the coherence of the received signal,on which some algorithms rely.This approach greatly limits the combat effectiveness and performance of the platform.Given the aforementioned problems and taking advantage of the target sparsity,a cross-validation multipath matching pursuit technique based on the sparse DOA estimation of an acoustic vector array is proposed in this article for sonar observations.The proposed algorithm uses cross-validation technology to achieve a sparse DOA estimation with an unknown number of targets in a sonar observation scene.Compared with the conventional acoustic vector array-based Capon algorithm,the proposed algorithm can achieve a sparse DOA estimation and high-resolution capability with small numbers of snapshots or even single snapshots.The effectiveness of the proposed algorithm is verified via simulations and sea t

关键词： multipath estimation underwater

Locally differentially private distributed algorithms for set intersection and union

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Science China(Information Sciences) 2021年第11期64卷 234-236页

作者： Qiao XUE youwen ZHU Jian WANG Xingxin LI Ji zhang College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Collaborative Innovation Center of Novel Software Technology and Industrialization Faculty of Health Engineering and Science University of Southern Queensland

Dear editor,Privacy-preserving distributed set intersection and union(PPSI, PPSU) have received much attention in recent years because of their wide applications. Most of existing solutions [1, 2] utilize secure multiparty computation protocols(SMCP) [3, 4] to settle the problem, but the SMCP methods are expensive in computation and communication. Even worse, most SMCP methods hardly continue to work if some participants disconnect.

关键词： local differential privacy set intersection union randomized response multiset

Cytokine receptor-like factor 1(CRLF1)promotes cardiac fibrosis via ERK1/2 signaling pathway

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2023年第8期24卷 682-697页

作者： Shenjian LUO Zhi YANG Ruxin CHEN Danming YOU Fei TENG youwen YUAN Wenhui LIU Jin LI Huijie zhang Department of Endocrinology and Metabolism Nanfang HospitalSouthern Medical UniversityGuangzhou 510515China Guangdong Provincial Key Laboratory of Shock and Microcirculation Southern Medical UniversityGuangzhou 510515China State Key Laboratory of Organ Failure Research Nanfang HospitalSouthern Medical UniversityGuangzhou 510515China Department of Endocrinology Shanxi Medical University Affiliated Second HospitalTaiyuan 030001China

Cardiac fibrosis is a cause of morbidity and mortality in people with heart disease.Anti-fibrosis treatment is a significant therapy for heart disease,but there is still no thorough understanding of fibrotic mechanisms.This study was carried out to ascertain the functions of cytokine receptor-like factor 1(CRLF1)in cardiac fibrosis and clarify its regulatory mechanisms.We found that CRLF1 was expressed predominantly in cardiac fibroblasts.Its expression was up-regulated not only in a mouse heart fibrotic model induced by myocardial infarction,but also in mouse and human cardiac fibroblasts provoked by transforming growth factor-β1(TGF-β1).Gain-and loss-of-function experiments of CRLF1 were carried out in neonatal mice cardiac fibroblasts(NMCFs)with or without TGF-β1 stimulation.CRLF1 overexpression increased cell viability,collagen production,cell proliferation capacity,and myofibroblast transformation of NMCFs with or without TGF-β1 stimulation,while silencing of CRLF1 had the opposite effects.An inhibitor of the extracellular signal-regulated kinase 1/2(ERK1/2)signaling pathway and different inhibitors of TGF-β1 signaling cascades,comprising mothers against decapentaplegic homolog(SMAD)-dependent and SMAD-independent pathways,were applied to investigate the mechanisms involved.CRLF1 exerted its functions by activating the ERK1/2 signaling pathway.Furthermore,the SMAD-dependent pathway,not the SMAD-independent pathway,was responsible for CRLF1 up-regulation in NMCFs treated with TGF-β1.In summary,activation of the TGF-β1/SMAD signaling pathway in cardiac fibrosis increased CRLF1 expression.CRLF1 then aggravated cardiac fibrosis by activating the ERK1/2 signaling pathway.CRLF1 could become a novel potential target for intervention and remedy of cardiac fibrosis.

关键词： Cytokine receptor-like factor 1(CRLF1) TGF-β1/SMAD signaling pathway ERK1/2 signaling pathway Cardiac fibrosis Myofibroblast transformation Extracellular matrix(ECM)

激光雷达电子行业助力自动驾驶汽车产业升级的路径研究

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激光杂志 2023年第5期44卷 215-218页

作者：张又文香港城市大学中国香港999077

激光雷达主流技术路线包括机械式、固态式和MEMS混合固态式三种类型,MEMS混合固态式较另外两种相比体积更小、探测距离更远、价格更低,但MEMS混合固态式激光雷达同样需要提升远距离、高分辨率快速扫描的能力,这是实现高级别自动驾驶技... 详细信息

激光雷达主流技术路线包括机械式、固态式和MEMS混合固态式三种类型,MEMS混合固态式较另外两种相比体积更小、探测距离更远、价格更低,但MEMS混合固态式激光雷达同样需要提升远距离、高分辨率快速扫描的能力,这是实现高级别自动驾驶技术的关键。激光雷达技术的进步将为自动驾驶汽车提供更加精准、可靠的环境感知,从而提高汽车的安全性和驾驶效率,推动自动驾驶汽车技术的革新。自动驾驶汽车技术变得更加成熟,市场认可度变得更高,更多人选择自动驾驶汽车,自动驾驶汽车将在汽车消费领域占据更大市场份额,进一步助力经济发展。

关键词：激光雷达自动驾驶多传感器产业升级

Influence of heat treatment on microstructure,mechanical and corrosion behavior of WE43 alloy fabricated by laser-beam powder bed fusion

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International Journal of Extreme Manufacturing 2024年第1期6卷 258-275页

作者： Chenrong Ling Qiang Li Zhe zhang youwen Yang Wenhao Zhou Wenlong Chen Zhi Dong Chunrong Pan Cijun Shuai College of Mechanical and Electrical Engineering Jiangxi University of Science and TechnologyGanzhou 341000People’s Republic of China School of Mechanical and Electronic Engineering Suzhou UniversitySuzhou 234000People’s Republic of China Shaanxi Key Laboratory of Biomedical Metal Materials Northwest Institute for Non-ferrous Metal ResearchXi’an 710016People’s Republic of China Department of Orthopedics First Afffliated Hospital of Gannan Medical CollegeGanzhou 341000People’s Republic of China School of Mechanical and Automotive Engineering South China university of technologyGuangzhou 510641People’s Republic of China State Key Laboratory of High-Performance Complex Manufacturing Central South UniversityChangsha 410083People’s Republic of China Double Medical Technology Inc. Xiamen 361026People’s Republic of China

Magnesium(Mg)alloys are considered to be a new generation of revolutionary medical metals.Laser-beam powder bed fusion(PBF-LB)is suitable for fabricating metal implants withpersonalized and complicated structures.However,the as-built part usually exhibits undesirable microstructure and unsatisfactory performance.In this work,WE43 parts were firstly fabricated by PBF-LB and then subjected to heat treatment.Although a high densification rate of 99.91%was achieved using suitable processes,the as-built parts exhibited anisotropic and layeredmicrostructure with heterogeneously precipitated Nd-rich intermetallic.After heat treatment,fine and nano-scaled Mg24Y5particles were precipitated.Meanwhile,theα-Mg grainsunderwent recrystallization and turned coarsened slightly,which effectively weakened thetexture intensity and reduced the anisotropy.As a consequence,the yield strength and ultimate tensile strength were significantly improved to(250.2±3.5)MPa and(312±3.7)MPa,respectively,while the elongation was still maintained at a high level of 15.2%.Furthermore,the homogenized microstructure reduced the tendency of localized corrosion and favoredthe development of uniform passivation film.Thus,the degradation rate of WE43 parts was decreased by an order of magnitude.Besides,in-vitro cell experiments proved their favorable biocompatibility.

关键词： laser-beam powder bed fusion WE43 alloys heat treatment mechanical performance biodegradation behavior

Hypericin enhances β-lactam antibiotics activity by inhibiting sarA expression in methicillinresistant Staphylococcus aureus

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Acta Pharmaceutica Sinica B 2019年第6期9卷 1174-1182页

作者： Genzhu Wang Liang Li Xiukun Wang Xue Li Youwen Zhang Jie Yu Jiandong Jiang Xuefu You Yan Q.Xiong Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center TorranceCA 90502USA Beijing Key Laboratory of Antimicrobial Agents Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Geffen School of Medicine at UCLA Los AngelesCA 90095USA State Key Laboratory of Bioactive Substances and Function of Natural Medicine Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Bacteremia is a life-threating syndrome often caused by methicillin-resistant Staphylococcus aureus(MRSA).Thus,there is an urgent need to develop novel approaches to successfully treat this infection.Staphylococcal accessory regulator A(SarA),a global virulence regulator,plays a critical role in pathogenesis andβ-lactam antibiotic resistance in Staphylococcus aureus.Hypericin is believed to act as an antibiotic,antidepressant,antiviral and non-specific kinase inhibitor.In the current study,we investigated the impact of hypericin onβ-lactam antibiotics susceptibility and mechanism(s)of its activity.We demonstrated that hypericin significantly decreased the minimum inhibitory concentrations ofβ-lactam antibiotics(e.g.,oxacillin,cefazolin and nafcillin),biofilm formation and fibronectin binding in MRSA strain JE2.In addition,hypericin significantly reduced sarA expression,and subsequently decreased mecAy and virulence-related regulators(e.g.,agr RNAIII)and genes(e.g.,fnbA and hla)expression in the studied MRSA strain.Importantly,the in vitro synergistic effect of hypericin withβ-lactam antibiotic(e.g.,oxacillin)translated into in vivo therapeutic outcome in a murine MRSA bacteremia model.These findings suggest that hypericin plays an important role in abrogation ofβ-lactam resistance againstMRSA through sarA inhibition,and may allow us to repurpose the use ofβ-lactam antibiotics,which are normally ineffective in the treatment of MRSA infections(e.g.,oxacillin).

关键词： Hyperiein β-Lactams MRSA Synergistic effect SarA