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An efficient method for the sanitary vitrification of bovine oocytes in straws

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Journal of Animal Science and Biotechnology 2014年第4期5卷 399-405页

作者： Yanhua Zhou xiangwei Fu Guangbin Zhou Baoyu Jia Yi Fang Yunpeng Hou Shien zhu National Engineering Laboratory for Animal Breeding Key Laboratory of Animal geneticsBreeding and ReproductionMinistry of AgricultureCollege of Animal Science and TechnologyChina Agricultural University Institute of Animal Genetics and Breeding College of Animal Science and TechnologySichuan Agricultural University(Chengdu Campus) State Key Laboratory for Agrobiotechnology College of Biological SciencesChina Agricultural University

Background：At present,vitrification has been widely applied to humans,mice and farm *** improve the efficiency of vitrification in straw,bovine oocytes were used to test a new two-step vitrification method in this ***：When in vitro matured oocytes were exposed to 20%ethylene glycol（EG20） for 5 min and 40%ethylene glycol（EG40） for 30 s,followed by treatment with 30%glycerol（Gly30）,Gly40 or Gly50,a volume expansion was observed in Gly30 and Gly40 but not *** indicates that the intracellular osmotic pressure after a 30 s differs between EG40 and ranged between Gly40（approximately 5.6 mol/L） and Gly50（approximately 7.0 mol/L）.Since oocytes are in EG40 just for only a short period of time（30 s） and at a lower temperature（4℃）,we hypothesize that the main function of this step in to induce *** on these results,we omitted the EG40 step,before oocytes were pretreated in EG20 for 5 min,exposed to pre-cooled（4℃） Gly50,for 30 s,and then dipped into liquid *** warming,81.1%of the oocytes survived,and the surviving oocytes developed into cleavage stage embryos（63.5%） or blastocysts（20.0%） after parthenogenetic ***：These results demonstrate that in a two-step vitrification procedure,the permeability effect in the second step is not *** is possible that the second step is only required to provide adequate osmotic pressure to condense the intracellular concentration of CPAs to a level required for successful vitrification.

关键词： Bovine Cryopreservation Oocytes Straw Vitrification

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变电站智能巡检机器人的应用研究

电力设备管理 2024年第8期 289-291页

作者：吴可可黄湘伟朱峰黄明星宋运团华能湖南清洁能源分公司华能新能源湘乡风力发电有限公司深圳昱拓智能有限公司

当前在变电站中,智能巡检机器人发挥着重要的作用,为电力运行提供了全面的保障。现阶段,提升巡检机器人系统的智能性、精确性是目前研究的要点。基于此,本文通过提出整体框架设计,为运动规划设计奠定良好基础,并结合实际情况探讨智能巡... 详细信息

当前在变电站中,智能巡检机器人发挥着重要的作用,为电力运行提供了全面的保障。现阶段,提升巡检机器人系统的智能性、精确性是目前研究的要点。基于此,本文通过提出整体框架设计,为运动规划设计奠定良好基础,并结合实际情况探讨智能巡检机器人在变电站中的应用,以达到较好的效果。

关键词：变电站智能巡检机器人功能模块

基于机器学习和土壤关键要素的烤烟品质数字制图——以云南玉溪烟区为例

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土壤 2024年第4期56卷 879-888页

作者：陶怡王美艳史学正孙维侠王世航李湘伟朱云聪谢新乔中国科学院南京土壤研究所南京211135 安徽理工大学空间信息与测绘工程学院安徽淮南232001 红塔烟草(集团)有限责任公司云南玉溪653100

以中国典型烟区云南玉溪烟区为研究对象,基于156个土壤–烤烟品质等级配对数据集,通过主成分分析法筛选土壤关键要素,应用反向神经网络(BPNN)、随机森林(RF)和支持向量机(SVM)3种机器学习方法,构建了基于土壤关键要素的烤烟品质等级预... 详细信息

以中国典型烟区云南玉溪烟区为研究对象,基于156个土壤–烤烟品质等级配对数据集,通过主成分分析法筛选土壤关键要素,应用反向神经网络(BPNN)、随机森林(RF)和支持向量机(SVM)3种机器学习方法,构建了基于土壤关键要素的烤烟品质等级预测模型,实现了玉溪市烤烟品质等级空间预测与制图。研究结果表明:基于17个土壤指标筛选出11个指标作为土壤关键要素,其中土壤黏粒含量对烤烟品质等级的贡献率最大,为18.5%。独立验证结果显示,RF模型的准确率和Kappa系数最高,分别为0.78和0.76,预测效果最好,其次是SVM模型,BPNN模型最差。从召回率和精确率来看,RF模型对烤烟品质等级正确分级效果的程度为五档>一档>二档。一档、五档烤烟主要集中分布在玉溪市东部,最东部的华宁县是玉溪市最优质的烤烟作物产地。

关键词：烤烟品质机器学习土壤关键要素空间分布制图

Effects of porous clay ceramic rates on aeration porosity characteristics in a structurally degraded soil under greenhouse vegetable production

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Pedosphere 2021年第4期31卷 606-614页

作者： Quanbo YU Meiyan WANG Yutian TIAN Xuezheng SHI xiangwei LI Lingying XU Xinqiao XIE Yijie SHI Yuncong zhu State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) University of Chinese Academy of Sciences Beijing 100049(China) Hongta Tobacco Group Company Limited Yunnan 653100(China)

Soil structure degradation in greenhouse vegetable fields reduces vegetable production. Increasing aeration porosity is the key to ameliorating soil structure degradation. Thus, we tested the effect of a porous material, porous clay ceramic(PLC), on the amelioration of soil structure degradation under greenhouse vegetable production. A 6-month pot experiment was conducted with four PLC application levels based on volume, i.e., 0%(control), 5%(1 P), 10%(2 P), and15%(3 P) using Brassica chinensis as the test plant. At the end of the experiment, soil columns were sampled, and the aeration pore network was reconstructed using X-ray computed tomography(CT). The degree of anisotropy(DA), fractal dimension(FD), connectivity, aeration porosity, pores distribution, and shape of soil aeration pores and plant biomass were determined. The DA, FD, and connectivity did not significantly differ as the PLC application rate ***, aeration porosity significantly linearly increased. The efficiency of PLC at enhancing soil aeration porosity was 0.18% per Mg ha^(-1). The increase in aeration porosity was mainly due to the increase in pores > 2 000 μm, which was characterized by irregular pores. Changes in aeration porosity enhanced the production of B. chinensis. The efficiency of PLC at increasing the plant fresh weight was 0.60%, 3.06%, and 2.12% per 1% application rate of PLC for the 1 P, 2 P, and 3 P treatments, respectively. These results indicated that PLC is a highly efficient soil amendment that improves soil structure degradation by improving soil aeration under greenhouse conditions. Based on vegetable biomass, a 10% application rate of PLC was recommended.

关键词： aeration pore network mineral amendment pore size distribution soil physical property soil structure degradation

Cryopreservation of farm animal gametes and embryos:recent updates and progress

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Frontiers of Agricultural Science and Engineering 2019年第1期6卷 42-53页

作者： Zhengyuan HUANG Lei GAO Yunpeng HOU Shien zhu xiangwei FU National Engineering Laboratory for Animal Breeding/Key Laboratory of Animal Genetics Breeding and Reproduction of Ministry of Agriculture/College of Animal Science and TechnologyChina Agricultural University State Key Laboratory of Agrobiotechnology/College of Biological Sciences China Agricultural University

Cryopreservation has undergone tremendous advances and is widely used in animal production based on decades of study of cellular permeability, freezability and empirical generalization. Several improvement are particularly important: the cryopreservation protocol has been continuously re?ned over the years to achieve greater reproductive performance; cryoprotective agents are more effective and less toxic than previously; there has been signi?cant innovation in advanced cryopreservation systems and carriers. Despite this, there are still problems that urgently require practical solutions, such as remedies for cryodamage and encouraging the use of frozen–thawed porcine sperm in pig production.

关键词： vitrification gametes embryo animal production cryoprotective agent freezability

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球磨工艺对几种硝酸盐形貌与结构的影响

宜宾学院学报 2023年第6期23卷 67-71页

作者：段海军崔超鹏朱向炜张世超李星月叶子胡昱琪淮北师范大学物理与电子信息学院安徽淮北235000

为了研究钼合金制备中球磨工艺对La(NO_(3))_(3)、Y(NO_(3))_(3)、Zr(NO_(3))_(4)的影响,用QM-3SP2行星式球磨机对原料进行干磨、湿磨处理,使用箱式电阻炉对原料以及干磨、湿磨处理后的试样进行焙烧处理,通过X射线衍射仪(XRD)和扫描电... 详细信息

为了研究钼合金制备中球磨工艺对La(NO_(3))_(3)、Y(NO_(3))_(3)、Zr(NO_(3))_(4)的影响,用QM-3SP2行星式球磨机对原料进行干磨、湿磨处理,使用箱式电阻炉对原料以及干磨、湿磨处理后的试样进行焙烧处理,通过X射线衍射仪(XRD)和扫描电子显微镜(SEM)对试样进行形貌和物相分析,观察球磨工艺对钼掺杂的第二相物相和形貌上的影响,结果发现:(1)干磨对试样的分散效果最好;湿磨对试样的混合效果最好.(2)焙烧后的最终产物是硝酸盐对应的氧化物.(3)球磨工艺对粉体的物相影响不大.(4)对干磨、湿磨以及焙烧处理后的硝酸盐进行分析,ZrO2作为第二相进行钼掺杂效果相对La_(2)O_(3)和Y_(2)O_(3)更好.

关键词：钼合金 La(NO3)3 Y(NO3)3 Zr(NO3)4 球磨焙烧

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主客体结构纳米半导体光催化的界面钉住效应

催化学报 1999年第3期20卷 297-300页

作者：吴鸣李文钊顾婉贞孙福侠朱相伟王复东林原肖绪瑞中国科学院大连化学物理研究所大连116023 中国科学院感光化学研究所北京100101

研究了主客体纳米结构ＺｎＳ半导体在光催化甲醇水溶液产氢同时产乙二醇反应中的界面“钉住效应”．认为在主体 β环糊精（ β ＣＤ）分子包覆作用下，客体ＺｎＳ的界面能带被钉住；溶液酸碱... 详细信息

研究了主客体纳米结构ＺｎＳ半导体在光催化甲醇水溶液产氢同时产乙二醇反应中的界面“钉住效应”．认为在主体 β环糊精（ β ＣＤ）分子包覆作用下，客体ＺｎＳ的界面能带被钉住；溶液酸碱性的变化，在很大程度上通过改变溶液相中各种氧化还原电对来间接影响客体的界面电荷输出行为．由此观点出发，并结合已有的光电实验结果，解释了主客体包容物ＺｎＳ／ β ＣＤ的最高光催化产氢活性发生在溶液ｐＨ＝１０～１１的实验现象．

关键词：钉住效应半导体硫化锌甲醇乙二醇氢光催化

Effects of the TLR4 transgene on reproductive traits and DNA methylation pattern of oocytes in ewes

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Frontiers of Agricultural Science and Engineering 2014年第4期1卷 314-320页

作者： Yi FANG xiangwei FU Junjie LI Ming DU Baoyu JIA Jinlong ZHANG Xiaosheng ZHANG Shien zhu National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics Breeding and Reproduction of Ministry of AgricultureCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China College of Animal Science and Technology Agricultural University of HebeiBaoding 071000China Animal Husbandry and Veterinary Research Institute of Tianjin Tianjin 300412China

This study was conducted to systematically assess the reproductive performance of transgenic TLR4 *** the TLR4 transgenic founders(F_(0))and their positive offspring(F_(1)),hematological and reproductive parameters and the global DNA methylation level in oocytes at various stages were *** values of the physiological and biochemical parameters determined from the blood samples did not differ significantly between the transgenic and wild-type ***,the transgenic ewes showed reproductive traits similar to the wildtype *** traits included characteristics of puberty,the estrus cycle,estrus duration,gestation,the pregnancy rate and the superovulation ***,no significant differences were found between transgenic and wild-type ewes in the DNA methylation level of the oocytes at various *** summary,the preliminary evidence presented in this paper demonstrates that the presence of the TLR4 transgene did not affect the reproductive performance in sheep.

关键词： TLR4 transgenic ewe safety assessment reproductive trait oocyte DNA methylation

Spatial changes and driving factors of lake water quality in Inner Mongolia, China

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Journal of Arid Land 2023年第2期15卷 164-179页

作者： REN Xiaohui YU Ruihong LIU Xinyu SUN Heyang GENG Yue QI Zhen ZHANG zhuangzhuang LI xiangwei WANG Jun zhu Penghang GUO Zhiwei WANG Lixin XU Jifei Inner Mongolia Key Laboratory of River and Lake Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China Key Laboratory of Mongolian Plateau Ecology and Resource Utilization Ministry of EducationHohhot 010021China

Lakes play important roles in sustaining the ecosystem and economic development in Inner Mongolia Autonomous Region of China,but the spatial patterns and driving mechanisms of water quality in lakes so far remain *** study aimed to identify the spatial changes in water quality and the driving factors of seven lakes(Juyanhai Lake,Ulansuhai Lake,Hongjiannao Lake,Daihai Lake,Chagannaoer Lake,Hulun Lake,and Wulannuoer Lake)across the longitudinal axis(from the west to the east)of Inner ***-scale research was conducted using the comprehensive trophic level index(TLI(Σ)),multivariate statistics,and spatial analysis *** results showed that most lakes in Inner Mongolia were weakly *** dissolved solids and salinity of lake water showed obvious zonation *** and phosphorus were identified as the main pollutants in lakes,with high average concentrations of total nitrogen and total phosphorus being of 4.05 and 0.21 mg/L,*** values of TLI(Σ)ranged from 49.14 to 71.77,indicating varying degrees of lake eutrophication,and phosphorus was the main driver of lake *** lakes of Inner Mongolia could be categorized into lakes to the west of Daihai Lake and lakes to the east of Daihai Lake in terms of salinity and TLI(Σ).The salinity levels of lakes to the west of Daihai Lake exceeded those of lakes to the east of Daihai Lake,whereas the opposite trend was observed for lake trophic *** intensity and mode of anthropogenic activities were the driving factors of the spatial patterns of lake water *** is recommended to control the impact of anthropogenic activities on the water quality of lakes in Inner Mongolia to improve lake ecological *** findings provide a more thorough understanding of the driving mechanism of the spatial patterns of water quality in lakes of Inner Mongolia,which can be used to develop strategies for lake ecosystem protection and water resources management i

关键词： salinity lake eutrophication lake water quality comprehensive trophic level index anthropogenic activities Daihai Lake Inner Mongolia