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predictors of microsurgical varicocelectomy efficacy in male infertility treatment:critical assessment and systematization

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Asian Journal of Andrology 2023年第1期25卷 21-28页

作者： Azizbek B Shomarufov Vladimir A Bozhedomov Nikolay I Sorokin Igor p Matyukhov Abdukodir A Fozilov Shukhrat A Abbosov Armais A Kamalov Department of Urology and Andrology Faculty of Fundamental MedicineLomonosov Moscow State UniversityMoscow 119991Russia Department of Urology Tashkent Medical AcademyTashkent 100109Uzbekistan Republican Specialized Scientific-practical Medical Center of Urology Tashkent 100109Uzbekistan

In this review,we tried to systematize all the evidence(from pubMed[MEDLINE],Scopus,Cochrane Library,EBSCO,Embase,and Google Scholar)from 1993 to 2021 on the predictors of microsurgical varicocelectomy efficacy in male infertility *** the outcomes of varicocele repair,we considered semen improvement and pregnancy and analyzed them *** on the 2011 Oxford CEBM Levels of Evidence,we assigned a score to each trial that studied the role of the *** systematized the studied predictors based on the total points,which were,in turn,calculated based on the number and quality of studies that confirmed or rejected the studied predictor as significant,into three levels of significance:predictors of high,moderate,and low clinical *** total motile sperm count(TMSC)coupled with sperm concentration can be a significant predictor of semen improvement and pregnancy after *** addition,for semen improvement alone,scrotal Doppler ultrasound(DUS)parameters,sperm DNA fragmentation index(DFI),and bilateral varicocelectomy are reliable predictors of microsurgical varicocelectomy efficacy.

关键词： male infertility microsurgical varicocelectomy predictor pregnancy semen varicocele

Liquid Metal Stirring in a Rectangular Cavity Generated by the Traveling Magnetic Field

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Journal of Iron and Steel Research International 2012年第S1期19卷 540-543页

作者： S.Yu.Khripchenko p.A.Oborin Institute of Continuous Media Mechanics UB RAS PermRussia perm State National Research polytechnical University PermRussia

This study examines the flow generated in a rectangular cavity by the traveling magnetic field and the transport of passive admixtures in the molten metal,as well as the effects of various parameters and parameter combinations on the flow intensity and admixture *** focus of the paper is on mathematical modeling and experimental investigation of the processes of admixture homogenization in the bulk of liquid metal subjected to electromagnetic *** obtained results can further be used to determine the optimal conditions for manufacture of high-quality alloys and to select the appropriate stirring process parameters.

关键词： MHD-stirring traveling magnetic field

Inflation, Dark Energy, Acceleration, Missing Mass?

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Journal of Modern physics 2021年第6期12卷 806-828页

作者： p. Christillin Dipartimento di Fisica Università di Pisa Pisa Italy

The black hole (b.h.) model based on the strong field treatment of the Newton potential is presented. The essential role of self energy both at the planck level and for matter and radiation at later stages supports the picture of an expanding Universe necessarily accompanied by particle creation if energy conservation applies at every scale. This process is shown to provide a gravitational repulsive force which can counterbalance gravitational attraction thus allowing the possibility of a steady expansion. This black hole treatment of our Universe evolution, questions the necessity of inflation. The role of the critical density to dictate the fate of the Universe is replaced by the black hole condition which entails a different relation between Hubble parameter and density thus disposing of dark energy. Since its predictions provide a different time development of the Universe also the evidence for its acceleration is disputed. That seems to provide a coherent scheme for our picture of the Universe evolution, based on Hubble’s law and backed up by the consideration of inertial forces. Newtonian angular momentum is also not conserved at cosmological scales. Finally we consider two coordinates systems. The conformally flat coordinates are shown to disprove inflation and the relevance of the painleve-Gullstrand metric in providing global coordinates is underlined. The combined effect of Hubble expansion and of proper time also questions the existence of missing mass.

关键词： Cosmogony Black Hole particle Creation Inflation Dark Energy Missing Mass

The Synthetic Evaluation of Warhead Overall Efficiency

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Journal of Systems Engineering and Electronics 2003年第1期14卷 12-17页

作者： Gu Xiaohui & Cao Bing College of Mechanics, Nanjing University of Science & Technology, Nanjing 210094, p. R. China College of Mechanics Nanjing University of Science & Technology Nanjmg 210094 P. R. China

The evaluation system of smart ammunition warhead overall efficiency has been established in this paper. Allkinds of evaluation methods have been analyzed. Having led the concept of hierarchical structure into technique for orderpreference by similarity to ideal solution (TOpSIS) method, we put forward the step TOpSIS method which is suitable forevaluating the overall efficiency of smart ammunition warheads. In the calculation of index weight, the graded weight cal-culus is put forward which hardly relies on the subjectivity of decision-makers and can reflect the sensitivity and compatibili-ty of the index. In the graded weight calculation, the proportional-arithmetic weight value calculus and sensitivity-compati-bility weight value calculus are given respectively.

关键词： Step analysis TOpSIS method Warhead Efficiency evaluation.

On the optimization problem of model-based monitoring

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Science China(Technological Sciences) 2011年第5期54卷 1095-1106页

作者： L. GINZINGER M. N. SAHINKAYA B. HECKMANN p. KEOGH H. ULBRICH Department of Mechanical Engineering Faculty of Engineering and Design University of Bath Institute of Applied Mechanics Technische Universitt München

Today there is a big interest in reducing the maintenance costs and in increasing the reliability of machines in continuous operation. Therefore, maintenance on condition is used. State-of-the-art is a trend analysis and a fault prediction made only based on sensor signals and stochastic methods. The identification possibilities of this technique are limited. A new concept for model-based monitoring has been developed for more detailed fault identification. The developed concept determines the condition of a machine after the occurrence of a fault. The concept is based on a simulation including various faults and an optimization tool. The development of a cost function and the optimization is one of the challenges of such a concept. Using an AMB rotor system with an auxiliary bearing, the new concept of model-based monitoring is investigated using experiments and the optimization is discussed in this paper.

关键词： model-based monitoring rotordynamics optimization

ZnSe Nanoparticles Reinforced Biopolymeric Soy protein Isolate Film

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Journal of Renewable Materials 2019年第8期7卷 749-761页

作者： Rakesh Kumar Reshma praveen Shikha Rani K.Sharma K.p.Tiwary K.Dinesh Kumar Department of Biotechnology Central University of South BiharGayaIndia Department of Applied Chemistry Birla Institute of Technology MesraPatna CampusPatnaIndia Department of Applied physics Birla Institute of Technology MesraPatna CampusPatnaIndia Department of Materials Science&Engineering Indian Institute of TechnologyPatnaIndia

ZnSe nanoparticles have been synthesized by microwave assisted method by using zinc chloride,selenium powder and ethylene *** synthesized nanoparticles have been characterized structurally by FT-IR and XRD as well as morphological characterization was done by scanning electron microscope(SEM).The crystallite size after synthesis was obtained around 30 nm for pure ZnSe ***,from SEM micrograph,agglomerated ZnSe nanoparticles of irregular shapes were *** as-synthesized ZnSe nanoparticles at different contents(1 to 5%w/w w.r.t SpI)were incorporated into soy protein isolate(SpI)to produce reinforced SpI films by solution casting *** ZnSe nanoparticles incorporated SpI suspensions were subjected to molecular mass and specific conductivity *** and ZnSe nanoparticles incorporated SpI films were structurally and mechanically characterized by FT-IR and tensile properties,*** and water uptake studies were also carried out for ZnSe nanoparticles incorporated SpI *** tensile strength and modulus increased from 5.80 Mpa to 10.06 Mpa and 18.84 Mpa to 94.70 Mpa with the increase in the contents of ZnSe nanoparticles from 0 to 5%.Moreover,the results also revealed a good antibacterial effect in ZnSe nanoparticles incorporated SpI *** main application of nanoparticles incorporated SpI film will be in the area of biodegradable packaging.

关键词： Soy protein isolate ZnSe nanoparticles reinforced film tensile properties antimicrobial properties

UNSTEADY pROpELLER SURFACE pRESSURE pREDICTION WITH A pOTENTIAL BASED pANEL METHOD

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Journal of Hydrodynamics 1995年第4期7卷 35-41页

作者： Chen Jia-dong(China Ship Scientific Research Center, Box 116, Wuxi 214082, p. R. China) China Ship Scientific Research Cent Wuxi China

A potential based panel method for unsteady propeller hydrodynamic analysis is presented,as to predict the unsteady hydrodynamic performance of a propeller subjected to a spatially non-uniform inflow. To satisfy the Kutta condition at the blade tailing rfgr well, a nonlinear pressure pressure condition, besides the linear Knits condition,is implemented at each time step by an iterative scheme, which enhances the precision of the preessure distribution over the blade surface. Some computation results are presented.

关键词： panel method propeller unsteady

Evolving properties of friction stir spot welds between AA1060 and commercially pure copper C11000

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Transactions of Nonferrous Metals Society of China 2016年第7期26卷 1852-1862页

作者： Mukuna p.MUBIAYI Esther T.AKINLABI Department of Mechanical Engineering Science Auckland Park Kingsway CampusUniversity of Johannesburg

Friction stir spot welding technique was employed to join pure copper （C11000） and pure aluminium （AA1060） sheets. The evolving properties of the welds produced were characterized. The spot welds were produced by varying the rotational speed, shoulder plunge depth using different tool geometries. The presence of a copper ring of different lengths was observed on both sides of the welds indicating that Cu extruded upward into the Al sheet which contributed to obtaining strong welds. The microstructure showed the presence of copper particles in the aluminium matrix which led to the presence of various intermetallics observed by the energy dispersive spectroscopy and X-ray diffraction. The maximum tensile failure load increases with an increase in the shoulder plunge depth, except for the weld produced at 800 r/min using a conical pin and a concave shoulder. A nugget pull-out failure mode occurred in all the friction stir spot welds under the lap-shear loading conditions. High peaks of Vickers microhardness values were obtained in the vicinity of the keyhole of most of the samples which correlated to the presence of intermetallics in the stir zone of the welds.

关键词： aluminium copper friction stir spot welding microhardness microstructure

Environmental engineering of transition metal dichalcogenide optoelectronics

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Frontiers of physics 2018年第4期13卷 21-52页

作者： Trevor LaMountain Erik J. Lenferink Yen-Jung Chen Teodor K. Stanev Nathaniel p. Stern Department of physics and Astronomy Northwestern University Evanston Illinois 60208 USA

The explosion of interest in two-dimensional van der Waals materials has been in many ways driven by their layered geometry. This feature makes possible numerous avenues for assembling and ma- nipulating the optical and electronic properties of these materials. In the specific case of monolayer transition metal dichalcogenide semiconductors, the direct band gap combined with the flexibility for manipulation of layers has made this class of materials promising for optoelectronics. Here, we review the properties of these layered materials and the various means of engineering these properties for optoeleetronics. We summarize approaches for control that modify their structural and chemical en- vironment, and we give particular detail on the integration of these materials into engineered optical fields to control their optical characteristics. This combination of controllability from their layered surface structure and photonic environment provide an expansive landscape for novel optoelectronic phenomena.

关键词： transition metal dichalcogenides optoelectronics van der Waals materials heterostructures excitons