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β-Adrenoceptors potentiate α1-adrenoceptor-mediated inotropic response in rat left atria

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Acta Pharmacologica Sinica 2004年第1期 31-36页

作者： Yong-zhen zhang, You-yi zhang, ming-zhe CHEN, Qi-de HANInstitute of Vascular Medicine, Peking University Third Hospital Key Laboratory of Ministry of Education for Molecular Cardiovasology, Beijing 100083, China

AIM: To investigate whether stimulation of β-adrenoceptor (AR) and its subtypes augment α1-AR-evoked positive inotropic response and inositol phosphate (InsP) accumulation in isolated rat left atria. METHODS: Inotropic response was determined by contractile function experiment in isolated electrically driven rat left atria. 3H-InsP accumulations were measured by 3H-inositol incorporation and column chromatography. RESULTS: (1)

关键词： alpha-1 adrenergic receptors beta adrenergic receptors heart atrium cardiac inotropism inositol phosphates adrenergic receptor antagonists adrenergic agonists

Cemented vertebra and adjacent vertebra refractured in a chronic kidney disease-mineral and bone disorder patient: A case report

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World Journal of Clinical Cases 2024年第10期12卷 1804-1809页

作者： Ti-Dong zhang Shuai Cao Hui-Yong Ren Yu-Min Li yi-ming Yuan Department of Orthopedics Civil Aviation General HospitalBeijing 100123China

BACKGROUND Although percutaneous vertebral augmentation(PVA)is a commonly used procedure for treating vertebral compression fracture(VCF),the risk of vertebral refracture should be *** kidney disease-mineral and bone disorder(CKD-MBD)is a systemic disease of mineral and bone *** is associated with an increased risk of *** studies have reported the use of PVA in patients with *** herein report a rare case wherein the cemented vertebra and the adjacent vertebra refractured simultaneously in a CKD-MBD patient after *** SUMMARY A 74-year-old man suffered from low back pain after taking a fall about 3 wk *** to physical examination,imaging and laboratory findings,diagnoses of T12 VCF,CKD-MBD,and chronic kidney disease stage 5 were *** then received percutaneous vertebroplasty at T12 *** weeks later,he presented with T12 and L1 vertebral refractures caused by lumbar *** again,he was given PVA which was optimized for the refractured *** the short-term postoperative effect was satisfactory,he reported chronic low back pain again at the 3-month *** It is necessary that patients with CKD-MBD who have received PVA are aware of the adverse effects of *** may increase the risk of vertebral ***,the PVA surgical technique needs to be optimized according to the condition of the *** medium-and long-term effects of PVA remain uncertain in patients with CKD-MBD.

关键词： Chronic kidney disease-mineral and bone disorder Percutaneous vertebral augmentation Vertebral compression fracture Vertebral refracture Cemented vertebra Adjacent vertebra Case report

Genomic divergence and mutation load in the Begonia masoniana complex from limestone karsts

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Plant Diversity 2024年第5期46卷 575-584页

作者： yiqing Chen Lina Dong Huiqin yi Catherine Kidner ming Kang Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China Guangzhou 510650China University of Chinese Academy of Sciences Beijing 100049China Guangxi Key Laboratory of Conservation and Restoration Ecology in Karst Terrain Guangxi Institute of BotanyGuangxi Zhang Autonomous Region and the Chinese Academy of SciencesGuilin 541006China Institute of Molecular Plant Sciences University of EdinburghDaniel Rutherford Building Max Born CrescentThe King's BuildingsEdinburgh EH93BFUK Royal Botanic Garden Edinburgh 20a Inverleith RowEdinburgh EH35LRUK State Key Laboratory of Plant Diversity and Specialty Crops South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China

Understanding genome-wide diversity,inbreeding,and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and ***,these effects are rarely studied in limestone karst ***,we re-sequenced the nuclear genomes of 62 individuals of the Begonia masoniana complex(***,***,*** and ***)and investigated genomic divergence and genetic load for these four *** analyses revealed four distinct clusters corresponding to each species within the ***,there was only limited admixture between *** and *** occurring in overlapping geographic *** species experienced historical bottlenecks during the Pleistocene,which were likely caused by glacial climate *** detected an asymmetric historical gene flow between group pairs within this timeframe,highlighting a distinctive pattern of interspecific divergence attributable to karst geographic *** found that isolated populations of *** have limited gene flow,the smallest recent population size,the highest inbreeding coefficients,and the greatest accumulation of recessive deleterious *** findings underscore the urgency to prioritize conservation efforts for these isolated *** study is among the first to disentangle the genetic differentiation and specific demographic history of karst Begonia plants at the whole-genome level,shedding light on the potential risks associated with the accumulation of deleterious mutations over generations of ***,our findings may facilitate conservation planning by providing critical baseline genetic data and a better understanding of the historical events that have shaped current population structure of rare and endangered karst plants.

关键词： Conservation genomics Karst landscape Demographic history Inbreeding Isolated populations Mutation load

Energy-Saving Distributed Flexible Job Shop Scheduling Optimization with Dual Resource Constraints Based on Integrated Q-Learning Multi-Objective Grey Wolf Optimizer

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1459-1483页

作者： Hongliang zhang yi Chen Yuteng zhang Gongjie Xu School of Management Science and Engineering Anhui University of TechnologyMa’anshan243032China Laboratory of Multidisciplinary Management and Control of Complex Systems of Anhui Higher Education Institutes Anhui University of TechnologyMa’anshan243032China Department of Industrial Engineering School of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an710072China

The distributed flexible job shop scheduling problem(DFJSP)has attracted great attention with the growth of the global manufacturing *** DFJSP research only considers machine constraints and ignores worker *** one critical factor of production,effective utilization of worker resources can increase ***,energy consumption is a growing concern due to the increasingly serious environmental ***,the distributed flexible job shop scheduling problem with dual resource constraints(DFJSP-DRC)for minimizing makespan and total energy consumption is studied in this *** solve the problem,we present a multi-objective mathematical model for DFJSP-DRC and propose a Q-learning-based multi-objective grey wolf optimizer(Q-MOGWO).In Q-MOGWO,high-quality initial solutions are generated by a hybrid initialization strategy,and an improved active decoding strategy is designed to obtain the scheduling *** further enhance the local search capability and expand the solution space,two wolf predation strategies and three critical factory neighborhood structures based on Q-learning are *** strategies and structures enable Q-MOGWO to explore the solution space more efficiently and thus find better Pareto *** effectiveness of Q-MOGWO in addressing DFJSP-DRC is verified through comparison with four algorithms using 45 *** results reveal that Q-MOGWO outperforms comparison algorithms in terms of solution quality.

关键词： Distributed flexible job shop scheduling problem dual resource constraints energy-saving scheduling multi-objective grey wolf optimizer Q-learning

N-Heterocyclic carbene-catalyzed enantioselective(dynamic) kinetic resolutions and desymmetrizations

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Science China Chemistry 2024年第2期67卷 482-511页

作者： yi zhang Hui Cai Xiuhai Gan Zhichao Jin National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityHuaxi DistrictGuiyang550025China

N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically *** content is organized according to the activation modes involved i... 详细信息

关键词： N-heterocyclic carbene kinetic resolution dynamic kinetic resolution desymmetrization organocatalysis

Supramolecular polymer-based gel fracturing fluid with a double network applied in ultra-deep hydraulic fracturing

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Petroleum Science 2024年第3期21卷 1875-1888页

作者： Yong-Ping Huang Yong Hu Chang-Long Liu yi-Ning Wu Chen-Wei Zou Li-Yuan zhang ming-Wei Zhao Cai-Li Dai School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Shandong Key Laboratory of Oilfield Chemistry China University of Petroleum(East China)Qingdao 266580ShandongPR China SINOPEC Petroleum Exploration and Production Research Institute Beijing102206PR China CNOOC China Co Ltd Tianjin BranchTianjin300459PR China

A gel based on polyacrylamide,exhibiting delayed crosslinking characteristics,emerges as the preferred solution for mitigating degradation under conditions of high temperature and extended shear in ultralong *** viscosity/viscoelasticity of the fracturing fluid was required to maintain excellent proppant suspension properties before *** into account both the cost and the potential damage to reservoirs,polymers with lower concentrations and molecular weights are generally *** this work,the supramolecular action was integrated into the polymer,resulting in significant increases in the viscosity and viscoelasticity of the synthesized supramolecular polymer *** double network gel,which is formed by the combination of the supramolecular polymer system and a small quantity of Zr-crosslinker,effectively resists temperature while minimizing permeability damage to the *** results indicate that the supramolecular polymer system with a molecular weight of(268—380)×10^(4)g/mol can achieve the same viscosity and viscoelasticity at 0.4 wt%due to the supramolecular interaction between polymers,compared to the 0.6 wt%traditional polymer(hydrolyzed polyacrylamide,molecular weight of 1078×10^(4)g/mol).The supramolecular polymer system possessed excellent proppant suspension properties with a 0.55 cm/min sedimentation rate at 0.4 wt%,whereas the0.6 wt%traditional polymer had a rate of 0.57 cm/*** comparison to the traditional gel with a Zrcrosslinker concentration of 0.6 wt%and an elastic modulus of 7.77 Pa,the double network gel with a higher elastic modulus(9.00 Pa)could be formed only at 0.1 wt%Zr-crosslinker,which greatly reduced the amount of residue of the fluid after *** viscosity of the double network gel was66 m Pa s after 2 h shearing,whereas the traditional gel only reached 27 m Pa s.

关键词： Ultra-deep reservoir Gel fracturing fluid Double network Supramolecular polymer system Proppant suspension property

Mechanical Performance of Bio-inspired Bidirectional Corrugated Sandwich Pressure Shell Under External Hydrostatic Pressure

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China Ocean Engineering 2024年第2期38卷 297-312页

作者： zhang yi CHEN Yue YUN Lai LIANG Xu Ocean College Zhejiang UniversityZhoushan 316000China Hainan Institute Zhejiang UniversitySanya 572000China

This paper aims to enhance the compression capacity of underwater cylindrical shells by adopting the corrugated sandwich structure of *** cuttlebone suffers uniaxial external compression,while underwater cylindrical shells are in a biaxial compressive stress *** suit the biaxial compressive stress state,a novel bidirectional corrugated sandwich structure is proposed to improve the bearing capacity of cylindrical *** static and buckling analysis for the sandwich shell and the unstiffened cylindrical shell with the same volume-weight ratio are studied by numerical *** is indicated that the proposed sandwich shell can effectively reduce the ratio between circumferential and axial stress from 2 to 1.25 and improve the critical buckling load by about 1.63 *** simulation shows that optimizing and adjusting the structural parameters could significantly improve the advantage of the sandwich ***,the hydrostatic pressure tests for shell models fabricated by 3D printing are carried *** to the experimental results,the overall failure position of the sandwich shell is at the center part of the sandwich *** has been found the average critical load of the proposed sandwich shell models exceeds two times that of the unstiffened shell ***,the proposed bio-inspired bidirectional corrugated sandwich structure can significantly enhance the pressure resistance capability of cylindrical shells.

关键词： bio-inspiration bidirectional corrugation sandwich shell external pressure buckling

Machine Learning Security Defense Algorithms Based on Metadata Correlation Features

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Computers, Materials & Continua 2024年第2期78卷 2391-2418页

作者： Ruchun Jia Jianwei zhang yi Lin College of Computer Science Sichuan UniversityChengdu610065China

With the popularization of the Internet and the development of technology,cyber threats are increasing day by *** such as malware,hacking,and data breaches have had a serious impact on *** network security environment in the era of big data presents the characteristics of large amounts of data,high diversity,and high real-time *** security defense methods and tools have been unable to cope with the complex and changing network security *** paper proposes a machine-learning security defense algorithm based on metadata association *** control over unauthorized users through privacy,integrity,and *** user model is established and the mapping between the user model and the metadata of the data source is *** analyzing the user model and its corresponding mapping relationship,the query of the user model can be decomposed into the query of various heterogeneous data sources,and the integration of heterogeneous data sources based on the metadata association characteristics can be *** and classify customer information,automatically identify and perceive sensitive data,build a behavior audit and analysis platform,analyze user behavior trajectories,and complete the construction of a machine learning customer information security defense *** experimental results show that when the data volume is 5×103 bit,the data storage integrity of the proposed method is 92%.The data accuracy is 98%,and the success rate of data intrusion is only 2.6%.It can be concluded that the data storage method in this paper is safe,the data accuracy is always at a high level,and the data disaster recovery performance is *** method can effectively resist data intrusion and has high air traffic control *** can not only detect all viruses in user data storage,but also realize integrated virus processing,and further optimize the security defense effect of user big data.

关键词： Data-oriented architecture metadata correlation features machine learning security defense data source integration

Synthesis of Diverse Oxetane Amino Acids via Visible-Light-Induced Photocatalytic Decarboxylative Giese-Type Reaction

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Chinese Journal of Chemistry 2024年第12期42卷 1341-1346页

作者： Haoliang Shi yi Wan Yongqiang zhang Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism Shanghai Key Laboratory of New Drug Designand School of PharmacyEast China University of Science and TechnologyShanghai200237 China

The divergent synthesis of versatile 3,3′-disubstituted oxetane amino acids by utilizing visible-light-induced photocatalytic decarboxylative Giese-type reaction has been demonstrated.3-Methyleneoxetane-derived substrates are readily available in a single-step and highly reactive as radical acceptors,allowing the production of versatile oxetaneγ-andα-amino acids in high yields.A distinct ring strain release-driven radical addition mechanism was preliminarily *** preparative power was further highlighted by the application in the synthesis of oxetane-containing dipeptides and azetidine amino acids,as well as the transformation of the product into novel oxetane-containing spiro-heterocycle pharmacophore.

关键词： Photoredox catalysis Decarboxylative Giese-type reaction Oxetane amino acids Amino acids Synthesis Radical reactions