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Intravenous injection of nicardipine changed the distribution of coronary artery endothelial shear stress and fluid dynamics in patients with unstable angina

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Chinese Medical Journal 2012年第18期125卷 3240-3245页

作者： CHEN Shao-liang HU Zuo-ying ZHANG Jun-jie KAN Jing xu Tian LIU Zhi-zhong xu hai-mei Department of Cardiology Nanjing First Hospital NanjingMedical University Nanjing China Jiangsu 210006

Background Coronary endothelial shear stress （ESS） triggered the development of atherosclerosis. However, the effect of calcium channel antagonist on the distribution of ESS remained unclear. Methods Twenty consecutive patients with acute coronary syndrome （ACS） 48 hours after maximal medication with single left anterior descending artery stenosis 〈50% were studied. Nicardipine was intravenously injected at 1 μg/kg after a bolus of 10 mg in order to achieve mean blood pressure （MBP） reduced by 10% or more, or the heart rate increased by 10-15 beats/min. Hemodynamic variables and angiogram at baseline and during injection of nicardipine were recorded, respectively. Coronary artery 3-D reconstruction was used for the analysis of ESS. Results Distal reference-vessel-diameter and minimal lumen diameter decreased significantly from （2.42±0.41） mm and （1.47±0.49） mm at baseline to （2.22±0.35） mm and （1.35±0.49） mm at maximal drug-dosage （P=0.018 and 0.020, respectively）. Nicardipine did not change blood velocity. Lowest mean shear stress at segments 2-mm distal to plaque increased significantly from （0.034±0.519） Pa at baseline to （0.603±0.728） Pa （P=0.013） at peak effect of drug. Conclusions Nicardipine was associated with the constriction of diseased vessel segment that adapted to the reduction of blood pressure, without dynamic change of blood velocity at each stage of whole cardiac cycle. Increased ESS value at segments distal to plaque reflected the cardioprotection by nicardipine （ChiCTR-TRC-10000964）.

关键词： nicardipine endothelial shear stress, blood hemodynamics

Recent Advances in Artificial Sensory Neurons:Biological Fundamentals,Devices,Applications,and Challenges

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Nano-Micro Letters 2025年第3期17卷 168-216页

作者： Shuai zhong Lirou Su Mingkun xu Desmond Loke Bin Yu Yishu Zhang Rong Zhao Guangdong Institute of Intelligence Science and Technology HengqinZhuhai 519031People’s Republic of China College of Integrated Circuits Zhejiang UniversityHangzhou 3112000People’s Republic of China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 310027People’s Republic of China Department of Science Mathematics and TechnologySingapore University of Technology and DesignSingapore 487372Singapore Department of Precision Instruments Tsinghua UniversityBeijing 100084People’s Republic of China Center for Brain‑Inspired Computing Research Tsinghua UniversityBeijing 100084People’s Republic of China IDG/McGovern Institute for Brain Research Tsinghua UniversityBeijing 100084People’s Republic of China

Spike-based neural networks,which use spikes or action potentialsto represent information,have gained a lot of attention because of their high energyefficiency and low power *** fully leverage its advantages,convertingthe external analog signals to spikes is an essential *** including analog-to-digital converters or ring oscillators,and sensorssuffer from high power and area *** efforts are devoted to constructingartificial sensory neurons based on emerging devices inspired by the biologicalsensory *** can simultaneously perform sensing and spike conversion,overcoming the deficiencies of traditional sensory *** review summarizesand benchmarks the recent progress of artificial sensory *** starts with thepresentation of various mechanisms of biological signal transduction,followed bythe systematic introduction of the emerging devices employed for artificial ***,the implementations with different perceptual capabilitiesare briefly outlined and the key metrics and potential applications are also ***,we highlight the challenges and perspectives for the future development of artificial sensory neurons.

关键词： Artificial intelligence Emerging devices Artificial sensory neurons Spiking neural networks Neuromorphic sensing

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期68卷 46-95页

作者： zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin xu Yu-Wu zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

Cobalamin-dependent radical S-adenosyl-L-methionine protein functions with a partner to successively methylate tricyclic indole alkaloid for chuangxinmycin maturation and derivatization

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Science China Chemistry 2025年第1期68卷 308-316页

作者： Sili Wang Jiancheng Huang Yanan Du Wei Huang Yufeng xue Xiaokun xu Guannan zhong Yuanyuan Shi Bin Hong Xiaoying Bian Wen Liu State Key Laboratory of Chemical Biology Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences State Key Laboratory of Microbial Technology Shandong University National Health Commission (NHC) Key Laboratory of Biotechnology for Microbial Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobalamin(Cbl)-dependent radical S-adenosyl-L-methionine(SAM) proteins constitute the largest collection of the radical SAM superfamily that has hundreds of thousands of individual members. Many of these proteins are involved in the biosynthesis of pharmaceutically important natural products to catalyze chemically demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indole alkaloid antibiotic with potent anti-infective activity, functionalization of the characteristic thiopyrano[4,3,2-cd]indole scaffold by regio-and stereoselective C3-methylation is believed to rely on a Cbl-dependent radical process, which, however, remained to be reconstituted biochemically. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl-dependent radical SAM protein, with Cxm9, a DUF5825family protein that shares no homology to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric complex that selectively catalyzes C3-methylation of the tricyclic indole-S-hetero ring system in a successive manner, achieving CXM and a recently identified, C3-dimethylated congener. Detailed biochemical characterization,isotope labeling, structural simulation and bioinformatics analysis rationalized the catalysis of the Cxm8/Cxm9 complex and particularly the necessity of the DUF5825 protein for C3-methylase activity. This is the first example that a Cbl-dependent protein acts with a partner to exhibit radical SAM activity.

关键词： cbl-dependent radical SAM protein biosynthesis chuangxinmycin stereoselective methylation

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太阳能冷管的机理与结构改进实验

上海交通大学学报 2004年第10期38卷 1635-1638页

作者：刘震炎赵惠忠徐海峰卢允庄上海交通大学机械与动力工程学院上海200030

阐述了对太阳能冷管及其结构和性能的研制及改进,采用真空集热方式和选择性涂层加强冷管对太阳能的吸收,以固化复合吸附剂提高吸附床的吸附和脱附性能.对冷管中的脱附动力学机理进行了实验研究,指出真空度是影响脱附速率的主要因素之一... 详细信息

阐述了对太阳能冷管及其结构和性能的研制及改进,采用真空集热方式和选择性涂层加强冷管对太阳能的吸收,以固化复合吸附剂提高吸附床的吸附和脱附性能.对冷管中的脱附动力学机理进行了实验研究,指出真空度是影响脱附速率的主要因素之一.该太阳能冷管型可以制冷又可以供热水,其制冷系数达0.193,制冷与供热的总性能系数为0.692.

关键词：太阳能冷管太阳能制冷与制热吸附制冷脱附动力学

Inhibitory gamma-aminobutyric acidergic neurons in the anterior cingulate cortex participate in the comorbidity of pain and emotion

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Neural Regeneration Research 2025年第10期20卷 2838-2854页

作者： Lu Guan Mengting Qiu Na Li Zhengxiang Zhou Ru Ye Liyan zhong Yashuang xu Junhui Ren Yi Liang Xiaomei Shao Jianqiao Fang Junfan Fang Junying Du Department of Neurobiology and Acupuncture Research Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Key Laboratory for Research of Acupuncture Treatment and Transformation of Emotional Diseases Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Fuchun Community Health Service Center of Fuyang District HangzhouZhejiang ProvinceChina

Pain is often comorbid with emotional disorders such as anxiety and *** of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairments in inhibitory gamma-aminobutyric acid *** review primarily aims to outline the main circuitry(including the input and output connectivity)of the anterior cingulate cortex and classification and functions of different gamma-aminobutyric acidergic neurons;it also describes the neurotransmitters/neuromodulators affecting these neurons,their intercommunication with other neurons,and their importance in mental comorbidities associated with chronic pain *** understanding on their role in pain-related mental comorbidities may facilitate the development of more effective treatments for these ***,the mechanisms that regulate gamma-aminobutyric acidergic systems remain *** is also unclear as to whether the mechanisms are presynaptic or *** exploration of the complexities of this system may reveal new pathways for research and drug development.

关键词： anterior cingulate cortex anxiety chronic pain circuit communication comorbidity depression gamma-aminobutyric acidergic neurons parvalbumin neurons synaptic transmission

Impregnating photo-stable gold precursor onto uncalcined TS-1 to boost catalytic hydro-oxidation of propane

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Science China Chemistry 2025年

作者： Zhihua Zhang Erchuan Yang Fan Liu Kesheng xu Yuxia zhong Jinwei Sun Shudong Shi xuezhi Duan Xinggui Zhou State Key Laboratory of Chemical Engineering East China University of Science and Technology

Immobilizing highly dispersed Au nanoparticles onto titanium silicalite-1 (TS-1) by a simple impregnation method under light is still a challenging *** this work,a high photostable Au precursor protected by thiol ligands was firstly synthesized,and the as-prepared Au precursor displayed excellent stability under light for over 30 days,while the Au precursor without thiol ligands formed precipitates after just 2 h under ***,the Au precursor protected by thiol ligands was immobilized on the external surface of uncalcined TS-1 (i.e.,TS-1-B) by the incipient wetness impregnation method (IWI method) to prepare Au/TS-1-B *** activity of as-prepared Au/TS-1-B catalyst in the hydro-oxidation of propane to acetone was 1.4 times higher than that of the catalyst prepared by the deposition-precipitation urea method (DPU method).The structures of the Au/TS-1-B catalysts prepared by different methods were analyzed by multiple *** to the Au/TS-1-B catalyst prepared by the DPU method,the Au/TS-1-B catalyst synthesized by the IWI method exhibited a narrower size distribution of Au nanoparticles and had more small Au particles (<2 nm),which is the main reason for its superior ***,the effects of gold loadings,reaction temperature and Si/Ti molar ratio on the catalytic performance of the Au/TS-1-B catalyst prepared by the IWI method were also *** addition,the Au/TS-1-B catalyst prepared by the IWI method also exhibited excellent stability for over 140 h.

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Palladium installed copper-organic framework for C–C coupling reactions

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Science China Chemistry 2025年

作者： Yu-Mei Wang Mei-Xia Tao Kai-Ming Mo xu Chen Shu-Hua zhong Elena S Shubina Guo-Hong Ning Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Supramolecular Coordination ChemistryJinan University A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences

The formation of C–C bonds is a crucial aspect of organic synthesis. Synthesists' long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis. This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic frameworks(CMOFs) based on copper cyclic trinuclear units(Cu-CTUs). By incorporating palladium ions into the imine-based framework JNM-7 through a straightforward immersion method, we achieved a notable enhancement in catalytic activity for critical C–C coupling reactions, including C–H arylation and Sonogashira cross-coupling. The resulting JNM-7-Pd demonstrated remarkable stability and recyclability, maintaining its efficiency over at least three cycles without any decline in efficiency.

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Estimation of velocity potential of water waves using a Luenberger-like observer

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Science China(Information Sciences) 2020年第12期63卷 139-152页

作者： Yang YU hai-Long PEI Cheng-zhong xu Key Laboratory of Autonomous Systems and Networked Control Ministry of EducationSouth China University of Technology Unmanned Aerial Vehicle Systems Engineering Technology Research Center of Guangzhou South China University of Technology LAGEPP University Claude Bernard-Lyon 1

We propose a Luenberger-like observer for a water wave system. The water wave dynamics are assumed to be governed by the linearized water wave equation(LWWE). Our proposed observer estimates the velocity potential of water waves by measuring only the surface wave elevation. The information of the water-wave velocity field is then extracted from the gradient of the velocity potential. It is shown that the estimation error of the observer converges exponentially to zero as time tends to infinity. Furthermore,we numerically solve the LWWE and observer equation by the finite difference method. The efficiency of our proposed numerical scheme and the performance of the observer are validated by numerical simulation results.

关键词： linearized water wave equation LWWE Luenberger-like observer numerical simulations