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淫羊藿提取物对老龄种公鸡精液品质、生殖内分泌激素及繁殖性能的影响

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动物营养学报 2024年第1期36卷 312-322页

作者：韩书宇孙海霞刘静郭梦宇代占辉安胜英刘观忠河北农业大学动物科技学院保定071000 保定兴芮农牧发展有限公司保定071000

本试验旨在探究不同水平淫羊藿提取物对老龄种公鸡精液品质、生殖内分泌激素及繁殖性能的影响。选取72只体重[(2.94±0.01)kg]相近、健康的65周龄大午金凤父母代种公鸡,随机分成4组,每组6个重复,每个重复3只,单笼饲养。对照组饲喂基础饲... 详细信息

本试验旨在探究不同水平淫羊藿提取物对老龄种公鸡精液品质、生殖内分泌激素及繁殖性能的影响。选取72只体重[(2.94±0.01)kg]相近、健康的65周龄大午金凤父母代种公鸡,随机分成4组,每组6个重复,每个重复3只,单笼饲养。对照组饲喂基础饲粮,试验Ⅰ、Ⅱ、Ⅲ组分别在基础饲粮中添加0.05%、0.10%和0.15%的淫羊藿提取物。饲养试验持续7周。试验第4周(69周龄)和第7周(72周龄)收集精液,测定精液品质;试验第4周和第7周采集血液,测定血清生殖内分泌激素水平;试验最后2周收集合格种蛋以重复为单位入孵,用于测定繁殖性能指标。结果显示:与对照组相比,1)试验第4周时,各试验组种公鸡精子活力显著提高(P<0.05),精子畸形率显著降低(P<0.05);试验Ⅱ、Ⅲ组有效精子数显著增加(P<0.05);试验Ⅱ组精子密度显著提高(P<0.05)。试验第7周时,试验Ⅱ、Ⅲ组种公鸡精液量显著增加(P<0.05);试验Ⅲ组精子活力显著提高(P<0.05)。2)试验第4周时,试验Ⅱ、Ⅲ组精浆谷草转氨酶(GOT)、谷丙转氨酶(GPT)活性显著降低(P<0.05);试验第7周时,试验Ⅲ组精浆GOT、GPT活性显著降低(P<0.05)。3)试验第4周时,各试验组精浆谷胱甘肽过氧化物酶(GSH-Px)活性极显著提高(P<0.01);试验Ⅱ、Ⅲ组精浆总抗氧化能力(T-AOC)显著提高(P<0.05)。试验第7周时,各试验组精浆总超氧化物歧化酶(T-SOD)活性显著提高(P<0.05);试验Ⅱ、Ⅲ组精浆丙二醛(MDA)含量显著降低(P<0.05);试验Ⅱ组精浆T-AOC显著提高(P<0.05)。4)试验第4周时,各试验组血清促性腺激素释放激素(GnRH)水平显著降低(P<0.05),血清促黄体素(LH)和睾酮(T)水平显著提高(P<0.05);试验Ⅱ、Ⅲ组血清促卵泡素(FSH)水平显著提高(P<0.05)。试验第7周时,各试验组血清GnRH水平极显著降低(P<0.01);试验Ⅱ、Ⅲ组血清FSH、LH水平显著提高(P<0.05);试验Ⅲ组血清T水平显著提高(P<0.05)。5)试验Ⅱ、Ⅲ组受精率和入孵蛋孵化率显著提高(P<0.05);试验Ⅲ组受精蛋孵化率和入孵蛋健雏率显著提高(P<0.05),死胚率显著降低(P<0.05)。综上所述,淫羊藿提取物可以通过调控生殖内分泌激素,提高精浆抗氧化能力,减少精子损伤,从而改善精液品质,提高老龄种公鸡的繁殖性能,且其在饲粮中的适宜添加量为0.15%。

关键词：淫羊藿提取物老龄种公鸡精液品质生殖内分泌激素繁殖性能

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聚合物微针阵列热压印成型仿真与试验研究

长沙理工大学学报（自然科学版） 2024年第2期21卷 68-76页

作者：成钢唐昆刘冠中刘子聪袁剑平胡永乐毛聪江麓机电集团有限公司工艺研究院湖南湘潭411100 长沙理工大学机械装备高性能智能制造关键技术湖南省重点实验室湖南长沙410114

【目的】针对聚合物微针阵列热压印成型过程中充型不完整、脱模后继续变形和应力集中等问题,将成型仿真与试验相结合,探究热压印成型参数对残余应力与平均填充深度的影响,以满足高精度批量制造聚合物微针阵列的需求。【方法】在聚合物... 详细信息

【目的】针对聚合物微针阵列热压印成型过程中充型不完整、脱模后继续变形和应力集中等问题,将成型仿真与试验相结合,探究热压印成型参数对残余应力与平均填充深度的影响,以满足高精度批量制造聚合物微针阵列的需求。【方法】在聚合物材料热-机械性能研究的基础上,建立微针阵列的有限元模型,分析热压印温度、热压印速率和下压量等成型参数对残余应力及其分布的影响,进行热压印成型试验,探讨相关成型参数对微针成型的影响,对比分析了平均填充深度仿真与试验值。【结果】随热压印温度的升高,最大成型应力呈先降后升的趋势;随热压印速率与下压量的增加,最大成型应力均呈增大的趋势;除热压印温度高于125℃之外,平均填充深度的仿真值与试验值变化趋势一致,且仿真值均高于试验值。此外,还获得了适用于聚苯乙烯微针阵列的最佳热压印参数,即热压印温度125℃、热压印速率10μm/s、下压量2.6 mm。【结论】在一定温度范围内,该数值仿真结果具有较高的指导意义,聚苯乙烯微针阵列结构的残余应力与平均填充深度具有较为敏感的温度与时间相关性。

关键词：聚合物微针阵列热压印有限元仿真填充深度

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Dynamic analysis of wind turbine tower structures in complex ocean environment

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Applied Mathematics and Mechanics(English Edition) 2020年第7期41卷 999-1010页

作者： guanzhong liu Xingming GUO Li ZHU Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Mathematics and Computational Sciences Xiangtan UniversityXiangtan 411105Hunan ProvinceChina

Studying and analyzing the dynamic behavior of offshore wind turbines are of great importance to ensure the safety and improve the efficiency of such expensive *** this work,a tapered beam model is proposed to investigate the dynamic response of an offshore wind turbine tower on the monopile foundation assembled with rotating blades in the complex ocean *** environment factors like wind,wave,current,and soil resistance are taken into *** proposed model is ana-lytically solved with the Galerkin *** on the numerical results,the effects of various structure parameters including the taper angle,the height and thickness of the tower,the depth,and the diameter and the cement filler of the monopile on the funda-mental natural frequency of the wind turbine tower system are investigated in *** is found that the fundamental natural frequency decreases with the increase in the taper angle and the height and thickness of the tower,and increases with the increase in the diameter of the ***,filling cement into the monopile can effectively im-prove the fundamental natural frequency of the wind turbine tower system,but there is a critical value of the amount of cement maximizing the property of the *** research may be helpful in the design and safety evaluation of offshore wind turbines.

关键词： wind turbine tower structure dynamic analysis tapered beam fundamen-tal natural frequency complex ocean environment

饲粮粗蛋白质水平对太行鸡种鸡生产性能、蛋品质和营养物质表观利用率的影响

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中国家禽 2024年第6期46卷 20-25页

作者：焦奕豪孙海霞唐如雪牛星月高启楠臧素敏周帆安胜英刘观忠河北农业大学动物科技学院河北保定071000 赞皇县天然农产品开发有限公司河北石家庄051230

试验旨在探究饲粮不同粗蛋白质(Crude protein,CP)水平对产蛋期太行鸡种鸡生产性能、蛋品质和营养物质表观利用率的影响。试验选取健康且产蛋率相近的37周龄太行鸡种鸡288只,随机分为4组,每组6个重复,每个重复12只鸡。各组饲粮CP水平分... 详细信息

试验旨在探究饲粮不同粗蛋白质(Crude protein,CP)水平对产蛋期太行鸡种鸡生产性能、蛋品质和营养物质表观利用率的影响。试验选取健康且产蛋率相近的37周龄太行鸡种鸡288只,随机分为4组,每组6个重复,每个重复12只鸡。各组饲粮CP水平分别为15.50%、16.00%、16.50%和17.00%。正式试验期为42 d。结果显示:①16.50%CP组产蛋率显著高于16.00%、17.00%CP组(P<0.05);16.50%CP组料蛋比极显著低于15.50%、16.00%和17.00%CP组(P<0.01),且饲粮粗蛋白质水平与料蛋比呈二次曲线关系(P=0.015)。②随着饲粮粗蛋白质水平的提高,蛋壳厚度线性升高(P<0.05),其中17.00%CP组蛋壳厚度显著高于15.50%CP组(P<0.05)。③不同粗蛋白质水平显著影响粗蛋白质和有机物表观利用率(P<0.05),16.50%CP组太行鸡粗蛋白质表观利用率显著高于其他组(P<0.05);16.50%CP组有机物表观利用率最高(P<0.01),其次依次为16.00%CP组、15.50%CP组和17.00%CP组(P<0.01),且随着饲粮粗蛋白质水平的提高,粗蛋白质和有机物表观利用率呈二次曲线关系(P<0.05)。综合料蛋比、粗蛋白质和有机物表观利用率指标,产蛋期太行鸡饲粮适宜粗蛋白质水平为16.20%~16.40%。

关键词：太行鸡粗蛋白质水平生产性能蛋品质表观利用率

藿香提取物对夏季蛋种鸡产蛋性能、内分泌激素、抗应激能力、抗氧化能力及繁殖性能的影响

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动物营养学报 2024年第2期36卷 956-967页

作者：孙海霞韩书宇刘静郭梦宇赵晓钰安胜英刘观忠河北农业大学动物科技学院保定071000 保定兴芮农牧发展有限公司保定071000

本试验旨在探究藿香提取物(ARE)对夏季蛋种鸡产蛋性能、蛋品质、内分泌激素水平、抗应激能力、抗氧化能力和繁殖性能的影响。选取288只65周龄、健康且产蛋率相近的大午金凤蛋种鸡,随机分成4组,每组6个重复,每个重复12只鸡。对照组饲喂... 详细信息

本试验旨在探究藿香提取物(ARE)对夏季蛋种鸡产蛋性能、蛋品质、内分泌激素水平、抗应激能力、抗氧化能力和繁殖性能的影响。选取288只65周龄、健康且产蛋率相近的大午金凤蛋种鸡,随机分成4组,每组6个重复,每个重复12只鸡。对照组饲喂基础饲粮,试验组分别饲喂在基础饲粮中添加0.05%(0.05%ARE组)、0.10%(0.10%ARE组)和0.15%(0.15%ARE组)藿香提取物的试验饲粮。预试期7 d,正试期49 d。结果显示:1)与对照组相比,0.15%ARE组蛋种鸡第1~49天产蛋率极显著提高(P0.05)。3)0.15%ARE组第49天血清中促性腺激素释放激素(GnRH)、雌二醇(E_(2))含量和促卵泡素(FSH)活性极显著高于其他组(P<0.01);0.10%ARE组第28天血清中FSH、促黄体生成素(LH)活性极显著高于对照组和0.05%ARE组(P<0.01)。4)与对照组相比,0.15%ARE组第49天血清中三碘甲状腺原氨酸(T_(3))、四碘甲状腺原氨酸(T_(4))含量显著提高(P<0.05),第28天血清中瘦素(LEP)含量极显著降低(P<0.01)。5)0.15%ARE组第28天血清中皮质酮(CorT)含量极显著低于对照组和0.10%ARE组(P<0.01),各试验组第49天血清中CorT含量极显著低于对照组(P<0.01);0.15%ARE组第28天和第49天血清中热休克蛋白70(HSP70)含量显著降低(P<0.05)。6)0.10%ARE组第28天血浆中总超氧化物歧化酶(T-SOD)活性和总抗氧化能力(T-AOC)极显著高于其他组(P<0.01);与对照组相比,各试验组第49天血浆中T-SOD活性极显著提高(P<0.01),丙二醛(MDA)含量显著降低(P<0.05)。7)0.05%ARE组种蛋受精率显著高于对照组和0.10%ARE组(P<0.05);与对照组和0.05%ARE组相比,0.15%ARE组种蛋死胚率显著降低(P<0.05),母鸡提供的健雏率显著提高(P<0.05)。综上所述,在饲粮中添加藿香提取物可以通过提高夏季蛋种鸡的抗应激能力和抗氧化能力来提高机体健康水平,同时可以调整机体内分泌,进而提高夏季蛋种鸡的产蛋性能和繁殖性能,并且本试验中以0.15%藿香提取物的应用效果最佳。

关键词：藿香提取物蛋种鸡产蛋性能内分泌激素抗应激能力抗氧化能力孵化性能

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A nonlocal strain gradient shell model incorporating surface effects for vibration analysis of functionally graded cylindrical nanoshells

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Applied Mathematics and Mechanics(English Edition) 2019年第12期40卷 1695-1722页

作者： Lu LU Li ZHU Xingming GUO Jianzhong ZHAO guanzhong liu Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy Engineering School of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072 China Department of Mechanical Engineering University of Alberta School of Mathematics and Computational Sciences Xiangtan UniversityXiangtan 411105 Hunan Province China

In this pap er, a novel size-dep endent functionally graded (FG) cylindrical shell model is develop ed based on the nonlocal strain gradient theory in conjunction with the Gurtin-Murdoch surface elasticity theory . The new model containing a nonlocal parameter, a material length scale parameter, and several surface elastic constants can capture three typical typ es of size e ects simultaneously , which are the nonlocal stress ef- fect, the strain gradient e ect, and the surface energy e ects. With the help of Hamilton’s principle and rst-order shear deformation theory , the non-classical governing equations and related b oundary conditions are derived. By using the prop osed model, the free vibra- tion problem of FG cylindrical nanoshells with material prop erties varying continuously through the thickness according to a p ower-law distribution is analytically solved, and the closed-form solutions for natural frequencies under various b oundary conditions are obtained. After verifying the reliability of the prop osed model and analytical method by comparing the degenerated results with those available in the literature, the in uences of nonlocal parameter, material length scale parameter, p ower-law index, radius-to-thickness ratio, length-to-radius ratio, and surface e ects on the vibration characteristic of func- tionally graded cylindrical nanoshells are examined in detail.

关键词： nonlocal strain gradient theory surface elasticity theory rst-order shear deformation theory vibration functionally graded (FG) cylindrical nanoshell

Ginger extract enhances antioxidant ability and immunity of layers

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Animal Nutrition 2019年第4期5卷 407-409页

作者： Shengying An guanzhong liu Xin Guo Yahui An Renyu Wang College of Animal Science and Technology Hebei Agricultural UniversityBaoding071000China

This experiment was to investigate ginger extract on production performance,antioxidant ability and immunity of laying hens.A total of 600 Hy-Line brown laying hens aged at 25 wk old were randomly divided into 2 treatments,4 replicates per treatment,75 layers each *** control group hens were fed a basal diet;the experimental group hens were fed basal diets with 0.1%ginger *** results were shown as follows:1)ginger extract significantly enhanced laying rates(P<0.05)and daily egg weight(P<0.05),substantially reduced the ratio of feed to egg(P<0.05)of the hens;2)ginger extract did not change the activities of glutathione peroxidase(GSH-PX)and total antioxidant capacity(TAOC)but significantly improved plasma superoxide dismutase(SOD)activity(P<0.05),reduced malondialdehyde(MDA)content(P<0.05)of the birds;3)ginger extract did not affect the contents of serum total protein(TP),albumin(ALB),globulin(GLB),but significantly increased lysozyme(LZM)activity(P<0.05);4)ginger extract also significantly reduced plasma prostaglandin E2(PGE2)content(P<0.05).This study shows that ginger extract not only can improve the birds’antioxidant capacity,enhance immune function,but also has a potential of reducing inflammatory response.

关键词： Antioxidant ability Immunity Ginger extract Layers Prostaglandin E2

Increased long-distance and homo-trans interactions related to H3K27me3 in Arabidopsis hybrids

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Journal of Integrative Plant Biology 2024年第2期66卷 208-227页

作者： Zhaoxu Gao Yanning Su Le Chang guanzhong Jiao Yang Ou Mei Yang Chao Xu Pengtao liu Zejia Wang Zewen Qi Wenwen liu Linhua Sun Guangming He Xing Wang Deng Hang He School of Advanced Agriculture Sciences and School of Life Sciences State Key Laboratory of Protein and Plant Gene ResearchPeking UniversityBeijing 100871China College of Grassland Science Beijing Forestry UniversityBeijing 100083China Peking University Institute of Advanced Agricultural Sciences Shandong Laboratory of Advanced Agricultural Sciences in WeifangWeifang 261325China

In plants,the genome structure of hybrids changes compared with their parents,but the effects of these changes in hybrids remain *** reciprocal crosses between Col×C24 and C24×Col in Arabidopsis using high-throughput chromosome conformation capture assay(Hi-C)analysis,we found that hybrid three-dimensional(3D)chromatin organization had more long-distance interactions relative to parents,and this was mainly located in promoter regions and enriched in genes with heterosis-related *** interactions between euchromatin and heterochromatin were increased,and the compartment strength decreased in *** compartment domain(CD)boundaries,the distal interactions were more in hybrids than their *** the hybrids of CURLY LEAF(clf)mutants clfCol×clfC24and clfC24×clfCol,the heterosis phenotype was damaged,and the long-distance interactions in hybrids were fewer than in their parents with lower ***-seq data revealed higher levels of H3K27me3 in the region adjacent to the CD boundary and the same interactional homo-trans sites in the wild-type(WT)hybrids,which may have led to more long-distance *** addition,the differentially expressed genes(DEGs)located in the boundaries of CDs and loop regions changed obviously in WT,and the functional enrichment for DEGs was different between WT and clf in the longdistance interactions and loop *** findings may therefore propose a new epigenetic explanation of heterosis in the Arabidopsis hybrids and provide new insights into crop breeding and yield increase.

关键词： 3D chromatin organization H3K27me3 homo-trans hybrids long-distanceinteractions

成果导向教育(OBE)理念和混合式教学模式在《牛生产学》课程中的应用探究

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中国畜禽种业 2024年第2期20卷 142-148页

作者：沈宜钊王莉秦仕达徐宏建李秋凤刘观忠高艳霞李建国河北农业大学河北保定071000

该文探讨了成果导向教育(OBE)理念和混合式教学模式在《牛生产学》课程中的应用。教学内容设计包括牛的生理、遗传、饲养等,采用多样化的教学方法,如围产期奶牛和不同泌乳期奶牛饲料配方配制案例研究和实验室配方软件应用实践等。评估... 详细信息

该文探讨了成果导向教育(OBE)理念和混合式教学模式在《牛生产学》课程中的应用。教学内容设计包括牛的生理、遗传、饲养等,采用多样化的教学方法,如围产期奶牛和不同泌乳期奶牛饲料配方配制案例研究和实验室配方软件应用实践等。评估方法综合考虑学生的理论学习和实践操作表现等。实施结果表明,这种教学模式显著提高了学生的学习兴趣、理解能力和批判性思维,体现了混合式教学在农业高等教育中的有效性和重要性。在《牛生产学》课程中,这种混合式教学模式可以帮助学生更深入地理解专业知识增强实践应用能力。

关键词：成果导向教育混合式教学牛生产学课程设计教学评估