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The association between the two more common genetic causes of spermatogenic failure:a 7-year retrospective study

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Asian Journal of Andrology 2020年第6期22卷 642-648页

作者： hong-ge li li-hong Fan Bei liu Ye-Qing Qian Min Chen Yi-Xi Sun Min-Yue Dong Women's Hospital School of MedicineZhejiang UniversityHangzhou 310006China

Chromosomal abnormalities and Y chromosome microdeletions are considered to be the two more common genetic causes of spermatogenic ***,the relati on ship between chromosomal aberrations and Y chromosome microdeletio ns is still un *** study was to investigate the incidenee and characteristics of chromosomal aberrations and Y chromosome microdeletions in infertile men,and to explore whether there was a correlation between the two genetic defects of spermatogenic failure.A 7-year retrospective study was conducted on 5465 infertile men with nonobstructive azoospermia or *** analysis of peripheral blood lymphocytes was performed by standard G-banding techniques.Y chromosome microdeletions were screened by multiplex PCR amplification with six specific sequence-tagged site(STS)*** the 5465 infertile men analyzed,371(6.8%)had Y chromosome microdeletions and the prevalence of microdeletions in azoospermia was 10.5%(259/2474)and in severe oligozoospermia was 6.3%(107/1705).A total of 4003(73.2%)infertile men underwent karyotyping;370(9.2%)had chromosomal abnormalities and 222(5.5%)had chromosomal *** analysis was performed on 272(73.3%)patients with Y chromosome microdeletions and 77(28.3%)had chromosomal aberrations,all of which involved sex chromosomes but not *** was a sign ifica nt d iff ere nee in the frequency of chromosomal abno rmalities betwee n men with and without Y chromosome microdeletions(P<0.05).

关键词： azoospermia factor chromosomal aberrations infertile men nonobstructive azoospermia and oligozoospermia spermatogenic failure Y chromosome microdeletions

Enhanced tensile properties and wear resistance of additively manufactured CoCrFeMnNi high-entropy alloy at cryogenic temperature

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Rare Metals 2022年第4期41卷 1210-1216页

作者： hong-ge li Peng-Cheng Che Xiao-Kun Yang Yong-Jiang Huang Zhi-liang Ning Jian-Fei Sun hong-Bo Fan School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Harbin-Electric Power generation Equipment National Engineering Research Center Co. LtdHarbin 150028China

Here,bulk CoCrFeMnNi high-entropy alloy was prepared via laser melting deposition,and its microstructure and mechanical properties at room and cryogenic temperature were investigated by a series of microstructural character-izations and mechanical *** results showed that the as-built samples possessed a single fcc phase and highly dense *** to the mechanical prop-erties at room temperature,tensile properties,microhard-ness and wear resistance of the as-built samples showed a signiflcant enhancement at cryogenic temperature,which was attributed to the deformation mechanism converting from dislocation slipping to deformation twinning at cryogenic *** formation of deformation nanotwins signiflcantly improved the deformation resis-tance in cryogenic conditions,and the sliding wear in the liquid nitrogen could decrease the oxygen concentration,suppress the generation of oxide particles and thus enhance the wear resistance.

关键词： wear cryogenic alloy

Effect of gravel content on the detachment of colluvial deposits in Benggang

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Journal of Mountain Science 2022年第11期19卷 3088-3104页

作者： ZHANG li-ting SHUAI Fang CHEN li-bo HUANG Yan-he liN Jin-shi ZHANG Yue ge hong-li JIANG Fang-shi Jinshan Soil and Water Conservation Research Center Fujian Agriculture and Forestry UniversityFuzhou 350002China

Accurately calculating detachment capacity is the most fundamental issue when establishing a soil erosion process *** deposits of Benggang are typical soil-gravel mixtures,whereas the understanding of the soil detachment of colluvial deposits is *** work investigated the effects of the gravel contents on the soil detachment capacity of colluvial deposits and its hydrodynamic *** colluvial sample was collected in Anxi County,Fujian Province,Southeast China,and a small-sample scouring test was *** slope steepness ranged from 18%to 84%,unit discharge ranged from 0.56×10^(-3)to 2.22×10^(-3)m^(2)s^(-1),and gravel content ranged from 0%to 70%.The results indicated that the gravel content is the primary factor that influences the detachment capacity,followed by the discharge and then the *** detachment capacity trend with the gravel content varied over different slopes and *** power represents the best hydrodynamic parameter for modelling the detachment capacity of colluvial deposits and can be used to establish a fitting equation for the colluvium together with the mean weight diameter(MWD)(Nash-Sutcliffe efficiency(NSE)=0.96).As the gravel content increased,the soil erodibility parameters increased several folds,in some cases more than 10 folds,mainly because the soil shear strength decreased ***,as the gravel content increased,the gravel specific surface area increased,the obstruction of gravel to runoff increased,and the energy needed for runoff to overcome gravel obstruction increased,leading to 2-3 folds higher critical shear stress of runoff for soilgravel mixtures compared with pure *** summary,gravel can influence the detachment capacity by changing the soil properties,and the gravel content also affects the relationship between soil detachment capacity and the hydrodynamic *** findings deepen the understanding of the influence of gravel on soil erosion and provide a basis for

关键词： Hydraulic erosion Hydrodynamics Gravel content Soil detachment Erosion resistance Benggang

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伊通地堑二号断层几何学特征及其与油气关系

石油地球物理勘探 2004年第5期39卷 614-617页

作者：李洪革李本才韩龙丁冶中国地质大学能源系东方地球物理公司研究院地质中心吉林油田分公司研究院

伊通地堑二号断层是依通地堑一条重要的断层 ,分隔鹿乡断陷及岔路河断陷 ,断层两侧发育有梁家和五星两个重要的含油气构造带。本文通过高质量的三维地震资料的精细解释 ,研究了二号断层的几何学特征 ,分析了其空间变化特征、动态演化特... 详细信息

伊通地堑二号断层是依通地堑一条重要的断层 ,分隔鹿乡断陷及岔路河断陷 ,断层两侧发育有梁家和五星两个重要的含油气构造带。本文通过高质量的三维地震资料的精细解释 ,研究了二号断层的几何学特征 ,分析了其空间变化特征、动态演化特征及其与油气运聚关系 ,认为二号断层不仅横切伊通地堑 ,而且具有控盆作用 ,向东与岔路河断陷的东部边界断层连为一体 ,其演化经历了早期张扭作用及晚期压扭作用 ,对两侧构造带发育具有明显控制作用 ,同时认为该断层是一条重要的油源断层 ,对油气成藏有重要控制作用。

关键词：伊通地堑断层几何学特征油气构造三维地震资料构造带油气运聚断陷油气成藏油源

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烷烃混合气体的太赫兹光谱分析

光谱学与光谱分析 2017年第7期37卷 2010-2013页

作者：冷文秀詹洪磊戈立娜中国石油大学(北京)油气光学探测技术北京市重点实验室北京102249

太赫兹时域光谱技术(THz-TDS)是近十多年发展起来的一种新的远红外光谱技术,在气体研究方面有了一定进展,尤其是对极性气体,而对非极性气体研究较少。本文以干馏气、天然气以及各种沼气的主要成分CH_4,C_2H_6和C_3H_8气体(非极性气体)... 详细信息

太赫兹时域光谱技术(THz-TDS)是近十多年发展起来的一种新的远红外光谱技术,在气体研究方面有了一定进展,尤其是对极性气体,而对非极性气体研究较少。本文以干馏气、天然气以及各种沼气的主要成分CH_4,C_2H_6和C_3H_8气体(非极性气体)为研究对象,首先对CH_4,C_2H_6和C_3H_8三种纯气进行测量,利用THz-TDS技术得到其太赫兹频域谱和相位谱,然后将其以不同比例、不同种类混合成二元气体,进一步研究混合气体的频域谱和相位谱。实验结果表明CH_4,C_2H_6对太赫兹波的吸收很小而C_3H_8对太赫兹波有一定的吸收,这与C_3H_8极性增强的物理特性相符合。为了实现对烷烃混合气体的压强和各成分浓度的定量分析,本文利用BP人工神经网络法对上述二元混合体系的太赫兹频域谱进行分析,对训练集和预测集分别计算了混合气体的压强和各成分浓度的预测值与实际值的相关系数,训练集和预测集的相关系数取值分别为0.994~0.999和0.981~0.993。研究表明,利用太赫兹时域光谱技术结合BP人工神经网络数学方法可以实现对烷烃混合气体的压强和各成分浓度的定量分析,使THz-TDS技术在气体领域研究范围更加广阔。

关键词：太赫兹时域光谱技术混合气体定量分析 BP人工神经网络

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铁皮石斛多糖含量的高光谱反演研究

光谱学与光谱分析 2014年第6期34卷 1645-1648页

作者：张银涛葛宏立孙贞邹红玉浙江农林大学浙江省森林生态系统碳循环与固碳减排重点实验室浙江临安311300 浙江农林大学天目学院浙江临安311300

铁皮石斛是我国传统的中草药,多糖含量是衡量其品质优劣的一个重要指标。主要研究铁皮石斛多糖含量与光谱间的关系,旨在寻找铁皮石斛多糖含量的无损检测方法。研究方法:实验材料选自不同处理铁皮石斛组培苗和不同生长阶段的驯化苗。其... 详细信息

铁皮石斛是我国传统的中草药,多糖含量是衡量其品质优劣的一个重要指标。主要研究铁皮石斛多糖含量与光谱间的关系,旨在寻找铁皮石斛多糖含量的无损检测方法。研究方法:实验材料选自不同处理铁皮石斛组培苗和不同生长阶段的驯化苗。其中36个样本作为建模样本建立模型,11个样本作为检验样本对模型进行检验。分别采用偏最小二乘回归法和因子分析法建立样本光谱与多糖含量间的关系。结果表明:(1)光谱一阶微分与多糖含量的相关性优于光谱反射率,其中对多糖含量较敏感的波段主要集中在可见光区域。(2)偏最小二乘回归法的模型决定系数最高,但其预测能力较差。因子分析法模型具有较好预测能力,基于光谱反射率因子分析模型和基于光谱一阶微分因子分析模型的相对分析误差分别为2.269和2.305。

关键词：铁皮石斛多糖高光谱偏最小二乘回归

Comprehensive genetic diagnosis of patients with Duchenne/Becker muscular dystrophy(DMD/BMD) and pathogenicity analysis of splice site variants in the DMD gene

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2019年第9期20卷 753-771页

作者： Yan-mei YANG Kai YAN Bei liU Min CHEN li-ya WANG Ying-zhi HUANG Ye-qing QIAN Yi-xi SUN hong-ge li Min-yue DONG Department of Reproductive genetics Women's HospitalSchool of MedicineZhejiang UniversityHangzhou 310006China Key Laboratory of Reproductive genetics(Zhejiang University) Ministry of EducationHangzhou 310006China Key Laboratory of Women's Reproductive Health of Zhejiang Province Hangzhou 310006China

Duchenne muscular dystrophy(DMD)and Becker muscular dystrophy(BMD)are caused by mutations in the DMD *** aim of this study is to identify pathogenic DMD variants in probands and reduce the risk of recurrence of the disease in affected *** in 100 unrelated DMD/BMD patients were detected by multiplex ligation-dependent probe amplification(MLPA)and next-generation sequencing(NGS).Pathogenic variants in DMD were successfully identified in all cases,and 11 of them were *** most common mutations were intragenic deletions(69%),with two hotspots located in the 5'end(exons 2–19)and the central of the DMD gene(exons 45–55),while point mutations were observed in 22%***,c.1149+1G>A and c.1150?2A>G were confirmed by hybrid minigene splicing assay(HMSA).This two splice site mutations would lead to two aberrant DMD isoforms which give rise to severely truncated ***,the clinical use of MLPA,NGS,and HMSA is an effective strategy to identify ***,eight embryos were terminated pregnancies according to prenatal diagnosis and a healthy boy was successfully delivered by preimplantation genetic diagnosis(PGD).Early and accurate genetic diagnosis is essential for prenatal diagnosis/PGD to reduce the risk of recurrence of DMD in affected families.

关键词： Dystrophin gene Variation genetic diagnosis Splice site mutation Hybrid minigene splicing assay

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我国能源经济复杂系统仿真研究

系统仿真学报 2002年第11期14卷 1443-1446页

作者：张宏民葛家理石油大学复杂性科学中心北京102249

针对传统“数量能源经济理论”的局限性,以“结构牵动论”代替传统数量能源观的“速度牵动论”,提出以产业结构和能源结构的双重优化来推动国民经济发展;同时又用“效益配置理论”代替传统能源经济的“热量平衡论”,将决策的能源总量,... 详细信息

针对传统“数量能源经济理论”的局限性,以“结构牵动论”代替传统数量能源观的“速度牵动论”,提出以产业结构和能源结构的双重优化来推动国民经济发展;同时又用“效益配置理论”代替传统能源经济的“热量平衡论”,将决策的能源总量,用泛函极值协调配置理论,以系统经济效益最优为目标进行了优化配置;人机结合的专家决策研讨厅利用可操作的杠杆调节以及调节后的信息反馈,可以实现能源经济复杂系统发展的社会目标。

关键词：能源经济学复杂系统专家研讨厅

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内在动机轮式倒立摆反应式认知系统

浙江大学学报（工学版） 2018年第6期52卷 1073-1080页

作者：赵传松任红格史涛李福进华北理工大学电气工程学院河北唐山063000

针对直线运动的轮式倒立摆常规自平衡控制方法存在自适应性差和鲁棒性差的问题,建立轮式倒立摆反应式认知系统,在与环境交互过程中涌现出自平衡控制规则.该系统由感知模块、执行模块和认知模块组成,前两者分别负责系统的输入与输出.认... 详细信息

针对直线运动的轮式倒立摆常规自平衡控制方法存在自适应性差和鲁棒性差的问题,建立轮式倒立摆反应式认知系统,在与环境交互过程中涌现出自平衡控制规则.该系统由感知模块、执行模块和认知模块组成,前两者分别负责系统的输入与输出.认知模块涉及到知识模型与学习策略:前者由连续动作学习自动机组构成,用于描述控制规则;后者负责优化知识模型,采用不确定性动机驱动的学习算法.详细描述该系统的结构、原理和算法,理论证明学习算法的收敛性,并通过仿真实验验证系统的自学习能力.结合常规PID和LQR算法通过仿真实验验证自适应性和鲁棒性.实验结果表明,该系统能够自主涌现出自平衡控制规则,表现出良好的自主学习认知技能,具有较好的自适应性与鲁棒性.

关键词：轮式倒立摆(WIP) 学习自动机不确定性动机反应式控制认知机器人