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Xenoesterogens and male infertility:myth or reality?

Asian Journal of Andrology 2000年第4期2卷 263-269页

作者： Roya Rozati p.p.Reddy p.Reddanna Rubina Mujtaba Assisted Conception Services Unit Mahavir Hospital and Research Centre Hyderabad(A. P.) 500 028 IndiaInstitute of Genetics and Hospital for Genetic Diseases Hyderabad IndiaDepartment of Animal Sciences School of Life Sciences University of Hyderabad IndiaAssisted Conception Services Unit Mahavir Hospital and Research Centre Hyderabad(A. P.) 500 028 India

Aim: To evaluate the role of polychlorinated biphenyls (pCBs) as a potential environmental hazard in the deteriora-tion of male fertility. Methods: Fifty-three males were studied. After a thorough case history evaluation and rele-vant clinical and laboratory investigations, pCBs were estimated in the seminal plasma of 21 infertile men with 'Unex-plained Male Factor' and 32 fertile controls. peak retention times of the eluants were compared with those of the com-mercially available standard pCB Mix, and the results confirmed spectrophotometrically. Seminal pCB concentrafonswere compared between i) fertile and infertile men and ii) men from different areas and diets. The relationship betweenpCB concentrations and measures of sperm quality such as the total motile sperm count, was assessed. Results:pCBs were detected in seminal plasma of infertile men but absent from controls. Sperm quantity and quality were sig-nificantly lower in infertile men compared to controls. The highest average pCB concentrations were found in fish-eat-ing urban dwellers, and followed in succession by fish-eating rural dwellers, non fish-eating urban dwellers and nonfish-eating mral dwellers. The total motile sperm counts were inversely proportional to the pCB concentrations and weresignificantly lower than those of the respective controls. Conclusion: pCBs may be instrumental in the deteriorationof sperm quantity and quality, a contaminated fish diet being the main source of exposure.(Asian J Androl 2000 Dec; 2: 263-269 )

关键词： polychlorinated biphenyls xenoestrogens male infertility sperm

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Kinetic energy distribution for neutron-induced fission of neptunium isotopes

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Chinese physics C 2021年第2期45卷 502-508页

作者： p Mehdipour Kaldiani Department of physics Naragh BranchIslamic Azad UniversityNaraghIran

The mean total kinetic energy as a function of fission fragments,thedistribution,is presented for neutron-induced fission of ^(235-239)Np using the scission point *** calculated results offor neutron-induced fission of ^(237,238) Np are compared with the available experimental data to obtain the deformation parameters in the scission point *** deformation parameters of fission fragments are discussed at the scission *** calculated results are also compared with the results from other methods and with experimental *** behavior of thedistribution is then studied for the neutron-induced fission of *** indicates that thevalues for neutron-induced fission of actinides with odd mass numbers are greater than for those with even mass numbers.

关键词： scission point model total kinetic energy neutron-induced fission fission fragments deformation parameters

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Elastic modulus and hardness of cortical and trabecular bovine bone measured by nanoindentation

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中国有色金属学会会刊：英文版 2006年第B02期16卷 744-748页

作者： HODGSON p D Centre for Material and Fibre InnovationDeakin University Geelong VIC 3217Australia

The elastic modulus and hardness of several microstructure components of dry bovine vertebrae and tibia have been investigated in the longitude and transverse directions using nanoindentation. The elastic modulus for the osteons and the interstitial lamellae in the longitude direction were found to be (24.7±2.5) Gpa and (30.1±2.4) Gpa. As it's difficult to distinguish osteons from interstitial lamellae in the transverse direction, the average elastic modulus for cortical bovine bone in the transverse direction was (19.8±1.6) Gpa. The elastic modulus for trabecular bone in the longitude and transverse direction were (20±2) Gpa and (14.7±1.9) Gpa respectively. The hardness also varied among the microstructure components in the range of 0.41-0.89 Gpa. Analyses of variance show that the values are significantly different.

关键词：牛骨弹性模量硬度骨皮质骨小梁纳米压痕法测量生物力学

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production of charmonium(like) states in e^+ e^- interactions

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Chinese physics C 2008年第6期32卷 488-491页

作者： p.pakhlov Institute for Theoretical and Experimental physics B.Cheremushkinskaya25117218MoscowRussia

We present a search for new charmonium like states in e^＋e^- annihilation using the initial-state radiation and the process e^＋e^- →J/ψ D（^＊）D（^＊）. The analyses are based on a huge data sample recorded near ... 详细信息

关键词： charmonium new states e^+e^- annihilation initial state radiation

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Recent progress of CERN RD50 Collaboration

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中国有色金属学会会刊：英文版 2006年第B01期16卷 133-136页

作者： p.LUUKKA Helsinki Institute of physics CERN /EPCH-1211 GenevaSwitzerland

The objective of the CERN RD50 Collaboration is to develop radiation hard semiconductor detectors for very high luminosity colliders, in particular, for the upgrade of the large hadron collider (LHC) which itself is scheduled to be operational in 2007. The approach of the RD50 has two major research lines, material engineering and device engineering. These are further subdivided into projects covering defect characterization and engineering, new detector materials, detector characterization, new detector structures and full detector systems. presently, 264 members from 53 institutes are actively participating in the RD50 Collaboration. Detectors made of defect engineered substrates, e.g. high resistivity magnetic Czochralski (MCz-Si), epitaxial silicon (Epi-Si) on Czochralski silicon (Cz-Si) substrate, intentionally thermal donor (TD) compensated p-type MCz-Si and oxygen enriched (DOFZ) silicon, have been demonstrated by the RD50 Collaboration. An overview and highlights of the results of these defect engineering techniques were given in this report.

关键词：欧洲原子能研究机构 RD50协作组辐射硬度半导体探测器成员单位研究进展直拉硅衬底

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Metaheuristics-based Clustering with Routing Technique for Lifetime Maximization in Vehicular Networks

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Computers, Materials & Continua 2023年第1期74卷 1107-1122页

作者： p.Muthukrishnan p.Muthu Kannan Saveetha School of Engineering Saveetha Institute of Medical and Technical SciencesSaveetha UniversitySaveetha NagarThandalamChennai602105TamilnaduIndia

Recently,vehicular ad hoc networks(VANETs)finds applicability in different domains such as security,rescue operations,intelligent transportation systems(ITS),*** has unique features like high mobility,limited mobility patterns,adequate topologymodifications,and wireless *** the benefits of VANET,scalability is a challenging issue which could be addressed by the use of cluster-based routing *** enables the vehicles to perform intercluster communication via chosen CHs and optimal *** main drawback of VANET network is the network unsteadiness that results in minimum *** order to avoid reduced network lifetime in VANET,this paper presents an enhanced metaheuristics based clustering with multihop routing technique for lifetime maximization(EMCMHR-LM)in *** presented EMCMHR-LM model involves the procedure of arranging clusters,cluster head(CH)selection,and route selection appropriate for *** presentedEMCMHR-LMmodel uses slime mold optimization based clustering(SMO-C)technique to group the vehicles into ***,an enhanced wild horse optimization based multihop routing(EWHO-MHR)protocol by the optimization of network *** presented EMCMHR-LMmodel is simulated usingNetwork Simulator(NS3)tool and the simulation outcomes reported the enhanced performance of the proposed EMCMHR-LM technique over the other models.

关键词： Scalability VANET clustering multihop routing metaheuristics route selection fitness function

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俄罗斯档案文件保管中的安全问题

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陕西档案 2011年第3期 43-45页

作者： Michael larin Sergey EGOROV 秦亚珊全俄档案与文件管理科学研究院(VNIIDAD)

俄罗斯联邦档案全宗是属于俄罗斯人民的国家财产。它包含了具有千年历史的俄罗斯的国家、经济、社会和文化生活的全球性信息。

关键词：俄罗斯联邦档案全宗安全问题文件保管国家财产文化生活全球性信息

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Experimental studies and phase field modeling of microstructure evolution during solidification with electromagnetic stirring

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中国有色金属学会会刊：英文版 2010年第S3期20卷 774-780页

作者： p.GERALD TENNYSON p.KUMAR H.LAKSHMI G.pHANIKUMAR p.DUTTA Department of Metallurgical and Materials Engineering Indian Institute of Technology National Facility for Semisolid Forming Department of Mechanical EngineeringIndian Institute of Science

Thixocasting requires manufacturing of billets with non-dendritic *** alloy A356 billets were produced by rheocasting in a mould placed inside a linear electromagnetic *** heat treatment was used to produce a transition from rosette to globular *** current and the duration of stirring were explored as control *** induction heating of the billet during stirring was quantified using experimentally determined thermal *** effect of processing parameters on the dendrite fragmentation was *** computational modeling of the process was performed using phase-field modeling of alloy solidification in order to gain insight into the process of morphological changes of a solid during this process.A non-isothermal alloy solidification model was used for *** morphological evolution under such imposed thermal cycles was simulated and compared with experimentally determined *** scaling using the thermosolutal diffusion distances was used to overcome computational difficulties in quantitative comparison at system *** results were interpreted in the light of existing theories of microstructure refinement and globularisation.

关键词： electromagnetic stirring non-dendritic phase field modeling microstructure

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Cryogenic and conventional milling of AZ91 magnesium alloy

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Journal of Magnesium and Alloys 2024年第6期12卷 2503-2519页

作者： Vikas Marakini Srinivasa pai p Gururaj Bolar Bhaskara p Achar Department of Mechanical Engineering Nitte(Deemed to be University)NMAM Institute of Technology(NMAMIT)Nitte 574110India Department of Mechanical and Industrial Engineering Manipal Institute of TechnologyManipal Academy of Higher EducationManipal 576104India

Use of magnesium is the need of the hour due to its low density as well as its high strength-to-weight and stiffness-to-weight ratio *** study focuses on the effectiveness of liquid nitrogen(LN_(2))assisted cryogenic machining on the surface integrity(SI)characteristics of AZ91 magnesium *** milling using uncoated carbide inserts have been performed under liquid nitrogen(LN_(2))assisted cryogenic condition and compared with conventional(dry)*** are performed using machining parameters in terms of cutting speeds of 325,475,625 m/min,feed rates of 0.05,0.1,0.15 mm/teeth and depth of cuts of 0.5,1,1.5 mm *** significant surface integrity characteristics such as surface roughness,microhardness,microstructure,and residual stresses have been *** of SI characteristics with respect to milling parameters have been identified using statistical technique such as ANOVA and signal-to-noise(S/N)ratio ***,the multi criteria decision making(MCDM)techniques such as additive ratio assessment method(ARAS)and complex proportional assessment(COpRAS)have been utilized to identify the optimal conditions for milling AZ91 magnesium alloy under both dry and cryogenic *** of LN_(2)during machining,resulted in reduction in machining temperature by upto 29%with a temperature drop from 251.2℃under dry condition to 178.5℃in cryogenic *** showed the advantage of performing cryogenic milling in improving the surface integrity to a significant *** machining considerably minimized the roughness by upto 28%and maximised the microhardness by upto 23%,when compared to dry *** speed has caused significant impact on surface roughness(95.33%-dry,92.92%-cryogenic)and surface microhardness(80.33%-dry,82.15%-cryogenic).Due to the reduction in machining temperature,cryogenic condition resulted in compressive residual stresses(maximumσ║=-113 Mpa)on the alloy *** indicate no

关键词： Magnesium alloy Cryogenic machining Roughness Microhardness Microstructure Residual stress Multi criteria decision making

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Restructuring of plasmonic nanoparticle aggregates with arbitrary particle size distribution in pulsed laser fields

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Chinese physics B 2016年第11期25卷 563-570页

作者： A E Ershov A p Gavrilyuk S V Karpov S p polyutov Institute of Computational Modeling Russian Academy of SciencesKrasnoyarsk 660036Russia L.V.Kirensky Institute of physics of the Russian Academy of Sciences Krasnoyarsk 660036Russia Siberian Federal University Krasnoyarsk 660028Russia Siberian State Aerospace University Krasnoyarsk 660037Russia

We have studied processes of interaction of pulsed laser radiation with resonant groups of plasmonic nanoparticles（resonant domains） in large colloidal nanoparticle aggregates having different interparticle gaps and particle size *** processes are responsible for the origin of nonlinear optical effects and photochromic reactions in multiparticle *** describe photo-induced transformations in resonant domains and alterations in their absorption spectra remaining after the pulse action,we introduce the factor of spectral *** on calculation of changes in thermodynamic,mechanical,and optical characteristics of the domains,the histograms of the spectrum photomodification factor have been obtained for various interparticle gaps,an average particle size,and the degree of *** in spectra have been analyzed depending on the intensity of laser radiation and various combinations of size characteristics of *** obtained results can be used to predict manifestation of photochromic effects in composite materials containing different plasmonic nanoparticle aggregates in pulsed laser fields.

关键词： resonant arbitrary pulsed dipole manifestation alterations extinction remaining aggregate colloidal

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