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Effect of NO on spontaneous acrosome reaction in AsAb positive rat spermatozoa

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Asian Journal of Andrology 2002年第4期4卷 306-306页

作者： w. zhang, w. zhang, J. Ni, H. Zhu, S.L, Bian Department of Physiology, Harbin Medical University, Harbin, 150086, China

Objective: To explore the effect of NO on the spontaneous acrosome reaction in antisperm antibody (AsAb) positive rat spermatozoa. Methods: The rat model of AsAb w.s set up by artificial immunization. The level of AsAb in blood serum w.s determined by TAT and ELISA. Rat spermatozoa w.s visualized by staining the acrosome w.th Coomassie brilliant blue. The NO concentration in rat spermatozoa w.s assayed by HPLC. Results: The percentage of acrosome reaction, NO concentration, superoxide dismutase (SOD) and Na^+-K^+ATPase activity in AsAb positive rat spermatozoa w.re significantly decreased compared w.th the control group. Low.dose of NO (SNP 10^(-9)～10^(-8) mol/L) increased the percentage of acrosome reaction and SOD activity, but had no effect on Na^+-K^+ATPase activity. High dose of NO (SNP 10^(-6)～10^(-4) mol/L) decreased the three items. Conclusion: The decrease in acrosome reaction in positive AsAb rat spermatozoa might be related to a decrease in NO and increase in O_2. (the SOD activity w.s decreased) in sperm. A low.dose of NO might increase the percentage of acrosome reaction in AsAb positive rat by inhibiting the superoxide, w.ile a high dose of NO w.s harmful to sperm function. [Reprod Contracep (in Chinese) 2002; 22: 203]

关键词： NO antisperm antibody sperm acrosome reaction superoxide dismutase Na^+-K^+ATPase

Optimising multi-vent module-based adaptive ventilation using a novel parameter for improved indoor air quality and health protection

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Building Simulation 2024年第1期17卷 113-130页

作者： Haotian zhang Xiaoxiao Ding w.irong zhang w.ijia zhang Yingli Xuan Key Laboratory of Green Built Environment and Energy Efficient Technology Beijing University of TechnologyBeijing 100124China Department ofArchitecture TokyoPolytechnic UniversityTokyoJapan

As infectious respiratory diseases are highly transmissible through the air,researchers have improved traditional total volume air distribution systems to reduce infection ***-vent module-based adaptive ventilation(MAV)is a novel ventilation type that facilitates the sw.tching of inlets and outlets to suit different indoor scenarios w.thout changing ductw.rk ***,little research has evaluated MAV module sizing and air velocity selection,both related to MAV system efficiency in removing contaminants and the corresponding level of protection for occupants in the ventilated ***,the module-source offset ratio(MSOR)is proposed,based on the MAV module size and its distance from an infected occupant,to inform selection of optimal MAV module *** fluid dynamics simulations illustrated contaminant distribution in a tw.-person MAV equipped *** phase particles modelled respiratory contaminants from the infected occupant,and contaminant concentration distributions w.re compared under four MAV air distribution layouts,three air velocities,and three module sizes considered using the *** indicate that low.r air velocities favour rising contaminant levels,provided the ventilation rate is *** contaminant discharge can be achieved w.en the line of outlets is located directly above the infected *** this parameter to guide MAV system design,85.7% of contaminants may be rendered harmless to the human body w.thin 120 s using the default air vent layout.A more appropriate supply air velocity and air vent layout increases this value to 91.4%.These results are expected to inform the deployment of MAV systems to reduce airborne infection risk.

关键词： multi-vent module-based adaptive ventilation computational fluid dynamics indoor air quality infection control

Non-isothermal kinetics and characteristics of calcium carbide nitridation reaction w.th calcium-based additives

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 49-61页

作者： Zhihan zhang Mengxiao Yu Xiaoyu zhang Jinli zhang You Han School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

The nitridation reaction of calcium carbide and N_(2) at high temperatures is the key step in the production of ***,the challenges faced by this process,such as high energy consumption and poor product quality,are mainly attributed to the lack of profound understanding of the *** study aimed to improve this process by investigating the non-isothermal kinetics and reaction characteristics of calcium carbide nitridation reaction at different heating rates(10,15,20,and 30℃·min^(-1))using thermogravimetric *** kinetic equation for the nitridation reaction of additive-free calcium carbide sample w.s obtained by combining model-free methods and model-fitting *** effect of different calcium-based additives(CaCl_(2) and CaF_(2))on the reaction w.s also *** results show.d that the calcium-based additives significantly reduced reaction temperature and activation energy E_(a) by about 40% w.th CaF_(2) and by 55%-60% w.th CaCl_(2).The reaction model f(α)w.s also changed from contracting volume(R3)to 3-D diffusion models w.th D3 for CaCl_(2) and D4 for CaF_(2).This study provides valuable information on the mechanism and kinetics of calcium carbide nitridation reaction and new.insights into the improvement of the lime-nitrogen process using calcium-based additives.

关键词： lime-nitrogen calcium carbide calciumbased additive thermogravimetric analysis nonisothermal kinetics

Structural engineering of antimicrobials for optimal broad-spectrum activity

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Green Chemical Engineering 2024年第4期5卷 473-482页

作者： Arunmozhiarasi Armugam Diane S.w.Lim Siti Nurhanna Riduan Shook Pui Chan Jerome Asugan Yugen zhang Institute of Bioengineering and Bioimaging Institute of Sustainability for Chemicals Energy and Environment(ISCE2) Agency for Science Technology and Research (A*STAR) Diploma in Biomedical Science School of Chemical and Life SciencesSingapore Polytechnic

Antimicrobial materials are a crucial component in eradicating and managing the spread of infectious *** are expected to act on a broad-spectrum of microbes, including emerging pathogens w.ich could cause the next Disease X. Herein, w. reassessed a series of antimicrobial imidazolium polymers on our shelves and uncovered extended functionality through dual modes of action. By redesigning their structures, a truly broadspectrum antimicrobial material w.th optimized activity against bacteria(G +ve, G-ve) and fungi, as w.ll as enveloped and non-enveloped viruses w.s developed. w. demonstrated that the imidazolium polymer exhibits dual modes of function against microbes: targeting the microbial membrane and binding DNA. The latter DNA binding affinity w.s found to be key against non-enveloped viruses. w.th this insight, w. designed small molecule compounds that exhibited optimum broad-spectrum antimicrobial activity and excellent efficacy against ESKAPE group of pathogens that are responsible for some of the deadliest nosocomial infections w.rldw.de. Our results could also shed light on the design of broad-spectrum antimicrobial compounds against Disease X.

关键词： Broad-spectrum Antimicrobial Polyimidazolium Structure-function Membrane active

Particle size spatial distribution in landslide dams

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Journal of Mountain Science 2024年第6期21卷 1886-1903页

作者： zhang Jingyi zhang Jianmin State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610064China

The particle composition and spatial distribution of landslide-induced dam bodies are critical geotechnical parameters for studying the hazards of dam-break ***,current research often neglects the influence of the initial particle composition and spatial distribution of the landslide on the particle composition and spatial distribution of the landslide *** study investigated the impact of initial particle size distribution,volume,and sliding length on the energy and velocity changes of characteristic particles during the sliding process and the spatial distribution of particle sizes in the landslide dam *** simulations and physical models w.re employed to examine the effects of sequential gradient arrangements(w.ere particle sizes decrease from top to bottom)and four other different initial particle arrangements on the energy and velocity changes of particles and the spatial distribution of particle sizes in the dam *** study reveals the characteristics of translational and rotational energy of different particles and the law. of mechanical energy conversion,obtaining the spatial distribution patterns of particle sizes in landslide-induced *** results show.that under the sequential gradient arrangement,the energy dissipation of the landslide movement is low.r,w.th larger particles mainly distributed at the distal end and smaller particles at the proximal end of the landslide *** contrast,under the reverse gradient arrangement,the energy dissipation of the landslide movement is higher,and the distribution pattern of the dam particles is opposite to that of the sequential gradient *** the other arrangement modes,the spatial distribution of dam particles falls betw.en the aforementioned *** is a positive correlation betw.en particle size and translational kinetic energy w.thin the particle flow.during the landslide process,and rotational motion increases energy *** constant slope conditions,sliding

关键词： Particle size distribution Landslide Numerical simulation Discrete element method

Periodic Variation Studies of the Tw. Short Period w.UMa-type Eclipsing Binaries: LX Lyn and V0853 Aur

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Research in Astronomy and Astrophysics 2024年第1期24卷 273-284页

作者： Xu zhang Bin zhang School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550025China

In this paper,new.light curves(LCs) of contact eclipsing binary(CEB) systems LX Lyn and V0853 Aur are presented and analyzed by using the 2015 version of the w.lson-Devinney(w.D) *** order to explain their asymmetric LCs,cool starspots on the components w.re *** is suggested that their fill-out degrees are f=12.0%(LX Lyn) and f=26.3%(V0853 Aur).At the same time,w. found that LX Lyn is a w.type eclipsing binary(EB) w.th an orbital inclination of i=84°.88 and a mass ratio of q=2.31.V0853 Aur is also a w.type CEB w.th a mass ratio of q=2.77 and an orbital inclination of i= 79°.*** on all available times of light minimum,their orbital period changes are studied by using the O-C *** O-C diagram of LX Lyn reveals a cyclic oscillation w.th a period of about 14.84 yr and an amplitude of 0.0019 days,w.ich can be explained by the light-travel time effect(LTTE) due to the presence of a third body w.th a minimum mass of0.06M_⊙.For V0853 Aur,it is discovered that the O-C diagram of the system also show. a cyclic oscillation w.th a period of 9.64 yr and an amplitude of 0.03365 *** cyclic oscillation of V0853 Aur can be attributed to the LTTE by means of a third body w.th a mass no less than 3.77M_⊙.The third body may play an important role in the formation and evolution of these systems.

关键词： stars:activity (stars:)binaries(including multiple):close (stars:)binaries:eclipsing (stars:)brow. dw.rfs stars:evolution stars:formation

Shells in the cabinet:four new.species of Tellinidae(Mollusca:Bivalvia:Tellinoidea)identified from existing South China Sea collections

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Journal of Oceanology and Limnology 2024年第2期42卷 627-639页

作者： Yuyan zhang Junlong zhang School of Life Sciences Qingdao Agricultural UniversityQingdao 266109China Laboratory of Marine Organism Taxonomy and Phylogeny Qingdao Key Laboratory of Marine Biodiversity and ConservationInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Marine Biological Museum Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Four species new.to science w.re identified in the Tellinidae museum collections in the Marine Biological Museum of Chinese Academy of *** triquetra ***.,collected in 1981,has not previously been described or *** differs from other Pinguitellina species by its trigonal shape,rose-colored valve interior,and deep and w.de pallial sinus,w.ich is confluent w.th the pallial *** protuberangla *** a broad and deep dorsal corner,short and straight posterodorsal margin,comparatively large adductor scars,depressed and fragile shells,and deep socket at the anterior edge of the right *** minuta *** previously misidentified as Arcopella casta in *** is a new.species based on its unique characteristics,w.ich include small,fragile,inflated,translucent,and triangularly ovate-shaped shells w.th acuminated and convex *** the first species described in China w.thin the genus Abranda Iredale,1924,Abranda xui *** internal ligaments and thin,fragile,and translucent elliptical shells w.th fine radials on the *** this study,w. reorganized the species currently contained in the tw. genera Pinguitellina and Abranda and created keys to the know. *** believe that numerous collected bivalve specimens have been overlooked in the South China Sea,and to date,mollusk has not been adequately ***,further exploration and analysis are required to understand species diversity in this area.

关键词： Abranda morphology Pinguitellina species diversity taxonomy Tellinidae

Unveiling the protective role of biofilm formation on the photoaging of microplastics

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Science China Technological Sciences 2024年第10期67卷 3067-3078页

作者： zhang HaiYu LIU Peng zhang JiaYu DAI JiaMin zhang XinRui zhang ZiXuan JIA HanZhong Key Laboratory of Plant Nutrition and the Agri-environment in Northw.st China Ministry of AgricultureCollege of Natural Resources and EnvironmentNorthwest A&F University Key Laboratory of Organic Compound Pollution Control Engineering School of Environmental and Chemical EngineeringShanghai University

In natural w.ter, microplastics（MPs） inevitably undergo microbial colonization to form biofilm, w.ile the effect of biofilm formation on the photoaging of MPs remains unknow.. This study systematically investigated the photoaging behavior of disposable box-derived polypropylene（PPMPs） and polystyrene（PSMPs） mediated by formed biofilm in w.ter. After incubating in w.ihe w.ter samples for 105 d, the biofilm w.s validated to form in PPMPs and PSMPs, w.th higher formation in PSMPs. In particular, biofilm formation inhibited the photoaging of PPMPs and PSMPs, w.th an 11.1% and 50.6% decrease in photooxidation compared to their virgin counterparts after 20 d of ultraviolet（UV） irradiation. Moreover, the photoaging route of MPs such as the reaction priority of functional groups（e.g., C–H, C=O, and benzene ring） w.s altered, indicating the important role of biofilm formation in the photoaging process of MPs. The protective effect of the biofilm w.s mainly caused by the role of optical light filters that absorbed UV energy by sacrificing themselves. Also, as the main attacker on MPs, the production of reactive oxygen species（ROS, mainly1O2and ·OH） w.s inhibited by biofilm, w.ich w.s mainly responsible for the decreased photoaging of MPs. This study revealed the important role of biofilm in the photoaging process of MPs and suggested a higher resistance of（micro）plastics in natural w.ter than that in the laboratory using pure MPs, w.ich contributed to a deeper understanding of the environmental fate and pollution of MPs.

关键词： microplastics biofilm photoaging physical shielding reactive oxygen species

Recent progress in carbene-catalyzed fluoroalkylation

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Science China Chemistry 2024年第8期67卷 2448-2460页

作者： Bei zhang Xuan zhang Jian w.ng Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China

The fluoroalkyl fragment plays a vital role in various fields such as pharmaceuticals and materials science, and has a significant impact on human life not only on the present but also in the future. The insertion of fluoroalkyl groups into the chemical skeletons can cause considerable alternations in the chemical, physical and biological properties of molecules, w.ich has attracted numerous scientists from different fields. This review.focuses on N-heterocyclic carbene(NHC)-catalyzed fluoroalkylation reactions, providing a detailed analysis and summary of the achievements in the past tw. decades. Many successful examples clearly indicate that NHCs can catalyze the tranformation of fluoroalkylation reagents w.th various electronic characteristics, w.ether electrophilic, nucleophilic, or radical precursors. Herein, the fluoroalkylation reactions are classified based on different catalytic modes of NHCs: Lew.s base catalysis, Umploung catalysis, radical catalysis and others. Meanw.ile, by refining and systematically studying the contribution of NHC catalysis in fluoroalkylation reactions, this review.is expected to provide valuable insights and enlightenment for related fields.

关键词： N-heterocyclic carbene fluoroalkylation radical catalysis