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Low dose gossypol for male contraception

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Asian journal of Andrology 2000年第4期2卷 283-287页

作者： Zhi-PingGU Bai-YongMAO yi-XinWANG Ren-AnZHANG Yong-ZhiTAN Zheng-XingCHEN LinCAO Gen-DiYOU s.j.segal shanghaiInstituteofMateriaMedica ChineseAcademyofSciencesShanghai200031China RenjiHospital ShanghaiSecondMedicalUniversityShanghai200001China ZhongshahHospital MedicalCentreofFudanUniversityShanghai200032China jingAnDistrictCentralHospital Shanghai200040China PopulationDivision RockefellerFoundationNewYorkUSA

Aim: To ascertain whether the side effects of gossypol, hypokalemia and irreversibility, could be avoided on dose re-duction. Methods: seventy-seven male volunteers were divided into 3 groups: control (22 cases), 10 mg gossypol(29 cases) and 12.5 mg (26 cases). serum levels of testosterone, FsH and LH were measured by RIA and potassiumby flame photometry. spema counts and motility were examined before and regularly after treatment for the evaluationof contraceptive efficacy. Results: The average sperm density and motility started to decrease significantly by theend of month 2 of medication and gradually reached the infertility levels ( s. Af-ter that the 10 mg group was asked to take the same dose every other day for up to a total observation period of 16-18months for the maintenance of infertility. subjects in the 12.5 mg group did not take gossypol any more so as to ob-serve the length of the loading dose required, but in a few, a maintenance dose of 12.5 mg every other day was insti-tuted for a few more months. In both treated groups, none of the spouses was pregnant during the maintenance dose pe-riod. serum levels of potassium, FsH, LH and testosterone were not significantly changed and not a single volunteercomplained of myoasthenia. After cessation of drug administratioin, the semen data returned to pretreatment ***: A regimen with 10 or 12.5 mg of gossypol as the daily loading dose and 35 or 43.75 mg as the week-ly maintenance dose could induce infertility in male volunteers without developing hypokalemia or irreversibility.(Asian j Androl 2000 Dec; 2: 283-287)

关键词： gossypol male contraceptive agents LH FsH testosterone serum potassium

石家庄s波段和X波段双偏振雷达定量降水估测应用研究

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高原气象 2025年第1期44卷 253-264页

作者：黄兆楚印佳楠杨洋张晓瑞黄毅王梧熠崔毅李禧亮河北省人工影响天气中心河北石家庄050021 河北省气象装备中心河北石家庄050021 河北省气象与生态环境重点实验室河北石家庄050021 石家庄市气象局河北石家庄050081

基于石家庄s波段雷达和X波段雷达、雨滴谱仪观测资料以及地面雨量计数据,分析两种雷达的R(ZH)、R(ZH,ZDR)、R(KDP)和R(KDP,ZDR)四种定量降水估测方法。结果表明,利用雨滴谱仪数据计算出的雷达反射率因子与雷达实测具有较好的一致性,但... 详细信息

基于石家庄s波段雷达和X波段雷达、雨滴谱仪观测资料以及地面雨量计数据,分析两种雷达的R(ZH)、R(ZH,ZDR)、R(KDP)和R(KDP,ZDR)四种定量降水估测方法。结果表明,利用雨滴谱仪数据计算出的雷达反射率因子与雷达实测具有较好的一致性,但整体偏大5 dB;两种雷达使用R(KDP,ZDR)方法估测降水结果优于其他方法,使用偏振参量KDP能明显提高降雨估测结果,使用ZDR后,测雨公式较单参量提高不明显;使用R(KDP)和R(KDP,ZDR)方法,利用X波段雷达估测降水的准确度略高于s波段雷达,可提升约10%,利用高空间分辨率的X波段雷达可以提升城市降水估测的精确度。

关键词：双偏振雷达雨滴谱定量估测降水(QPE)

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Influence of Liquid Isoprene Rubber on strain softening of Carbon Black Filled Isoprene Rubber Nanocomposites

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Chinese journal of Polymer science 2021年第7期39卷 887-895页

作者： Feng-yi Hou yi-Hu song Qiang Zheng MOE Key Laboratory of Macromolecular synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

The reinforcement of rubbers by nanoparticles is always accompanied with enhanced dissipation of mechanical energy upon large *** for solving the contradiction between improving reinforcement and reducing energy dissipation for rubber nanocomposites have not been well *** carbon black(CB)filled isoprene rubber(IR)/liquid isoprene rubber(LR)blend nanocomposites with similar crosslink density(ve)are prepared and influence of LR on the strain softening behaviors including Payne effect under large amplitude shear deformation and Mullins effect under cyclic uniaxial deformation is *** introduction of LR could improve the frequency sensitivity of loss modulus and reduce critical strain amplitude for Payne effect and loss modulus at the low ***,tuning ve and LR content allows reducing mechanical hysteresis in Mullins effect without significant impact on the mechanical *** investigation is illuminating for manufacturing nanocomposite vulcanizates with balanced mechanical hysteresis and reinforcement effect.

关键词： Rubber nanocomposites stress softening Mechanical hysteresis Liquid rubber

Gear Pitting Measurement by Multi-scale splicing Attention U-Net

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Chinese journal of Mechanical Engineering 2023年第2期36卷 140-154页

作者： yi Qin Dejun Xi Weiwei Chen yi Wang state Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing 400044China College of Mechanical Engineering Chongqing UniversityChongqing 400044China

The judgment of gear failure is based on the pitting area ratio of *** gear pitting calculation method mainly rely on manual visual *** method is greatly affected by human factors,and is greatly affected by the working experience,training degree and fatigue degree of the detection personnel,so the detection results may be *** non-contact computer vision measurement can carry out non-destructive testing and monitoring under the working condition of the machine,and has high detection *** improve the measurement accuracy of gear pitting,a novel multi-scale splicing attention U-Net(MssA U-Net)is explored in this *** image splicing module is first proposed for concatenating the output feature maps of multiple convolutional layers into a splicing feature map with more semantic ***,an attention module is applied to select the key features of the splicing feature *** that MssA U-Net adequately uses multi-scale semantic features,it has better segmentation performance on irregular small objects than U-Net and attention *** the basis of the designed visual detection platform and MssA U-Net,a methodology for measuring the area ratio of gear pitting is *** three datasets,experimental results show that MssA U-Net is superior to existing typical image segmentation methods and can accurately segment different levels of pitting due to its strong segmentation ***,the proposed methodology can be effectively applied in measuring the pitting area ratio and determining the level of gear pitting.

关键词： Gear pitting Image segmentation Attention module Computer vision Quantitative detection

(1+2)-Dimensional Radially symmetric Wave Maps Revisit

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Chinese Annals of Mathematics,series B 2022年第5期43卷 785-796页

作者： yi ZHOU school of Mathematical sciences Fudan UniversityShanghai 200433China

The author gives an alternative and simple proof of the global existence of smooth solutions to the Cauchy problem for wave maps from the(1+2)-dimensional Minkowski space to an arbitrary compact smooth Riemannian manifold without boundary, for arbitrary smooth, radially symmetric data. The author can also treat non-compact manifold under some additional assumptions which generalize the existing ones.

关键词： Cauchy problem Wave maps Global smooth solution

A Characterization of T_(2g+1,2) among Alternating Knots

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Acta Mathematica sinica,English series 2021年第12期37卷 1841-1846页

作者： yi NI Department of Mathematics CaltechMC 253-371200 E California BlvdPasadenaCA 91125USA

Let K be a genus g alternating knot with Alexander polynomial Δ_(K)(T)=Σ_(i=-g)^(g)a_(i)T^(i).We show that if |a_(g)|=|a_(g-1)|,then K is the torus knot T_(2g+1,±2).This is a special case of the Fox Trapezoidal ***... 详细信息

关键词： Alternating knots Alexander polynomial strongly quasipositive fibered knots

Feature screening for Ultrahigh-dimensional Censored Data with Varying Coefficient single-index Model

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Acta Mathematicae Applicatae sinica 2019年第4期35卷 845-861页

作者： yi LIU school of Mathematical sciences Ocean University of China

In this paper, we study the sure independence screening of ultrahigh-dimensional censored data with varying coefficient single-index model. This general model framework covers a large number of commonly used survival models. The property that the proposed method is not derived for a specific model is appealing in ultrahigh dimensional regressions, as it is difficult to specify a correct model for ultrahigh dimensional *** the assuming data generating process does not meet the actual one, the screening method based on the model will be problematic. We establish the sure screening property and consistency in ranking property of the proposed method. simulations are conducted to study the finite sample performances, and the results demonstrate that the proposed method is competitive compared with the existing methods. We also illustrate the results via the analysis of data from The National Alzheimers Coordinating Center(NACC).

关键词： censored data consistency in ranking property feature selection high-dimensional data sure screening property varying coefficient single-index model

Generalized Persistence of Entropy Weak solutions for system of Hyperbolic Conservation Laws

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Chinese Annals of Mathematics,series B 2022年第4期43卷 499-508页

作者： yi ZHOU school of Mathematical sciences Fudan UniversityShanghai 200433China

Let u(t,x)be the solution to the Cauchy problem of a scalar conservation law in one space *** is well known that even for smooth initial data the solution can become discontinuous in finite time and global entropy weak solution can best lie in the space of bounded total *** is impossible that the solutions belong to,for example,H^(1) because by sobolev embedding theorem H^(1) functions are Holder ***,the author notes that from any point(t,x),he can draw a generalized characteristic downward which meets the initial axis at y=α(t,x).If he regards u as a function of(t,y),it indeed belongs to H^(1) as a function of y if the initial data belongs to H^(1).He may call this generalized persistence(of high regularity)of the entropy weak *** main purpose of this paper is to prove some kinds of generalized persistence(of high regularity)for the scalar and 2×2 Temple system of hyperbolic conservation laws in one space dimension.

关键词： Quasilinear hyperbolic system Cauchy problem Entropy weak solution Vanishing viscosity method

Differential regulation of cPLA2 and iPLA2 expression in the brain

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Frontiers in Biology 2012年第6期7卷 514-521页

作者： Kazuhiro TANAKA Nikhat j. sIDDIQI Abdullah s. ALHOMIDA Akhlaq A. FAROOQUI Wei-yi ONG Neurobiology and Ageing Research Programme National University of Singapore Singapore 117456 Singapore Department of Biochemistry College of Science King Saud University Riyadh 11451 Saudi Arabia Department of Molecular and Cellular Biochemistry The Ohio State University Columbus OH 43210 USA Department of Anatomy National University of Singapore Singapore 119260 Singapore

The phospholipase A2 （PLA2） family members arc critical regulators of membrane structure and lipid composition and have been implicated in neuroinflammation, oxidative stress and neurodegeneration. Here, we review the published data describing regulation of cPLA2 and iPLA2 gene expression. Based on promoter sequence, cPLA2 expression can be regulated by glucocorticoid and pro-inflammatory cytokines, whereas transcription of iPLA2 can be controlled in response to sterol level. RNA degradation in 3＇ UTR and epigenetic mechanisms may be involved in the regulation of cPLA2 and iPLA2 expression, respectively. MicroRNA target sequences lie within cPLA2 and iPLA2 mRNAs. Together, these findings indicate differential regulation of cPLA2 and iPLA2 expression. It is hoped that determination of diverse regulatory mechanisms of the PLA2 family may open new doors for development of novel therapeutic compounds that modulate PLA2 expression and function in the treatment of brain diseases.

关键词： phospholipase A2 transcriptional regulation single nucleotide polymorphism miRNA