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α-酮戊二酸对湖羊精子质量与血浆生化指标的影响

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饲料工业 2024年第11期45卷 55-61页

作者：王赫川崔卫国张涵李天峰尹国安郭庆李井春黑龙江八一农垦大学动物科技学院黑龙江大庆163319

试验旨在研究东北地区秋季饲喂α-酮戊二酸对湖羊精子质量与血浆生化指标的影响,选择体况良好且体重相近的湖羊32只,随机平均分为4组,分别按只补饲0、5、10、20 g/dα-酮戊二酸。试验于8—10月在黑龙江伊春市开展,平均气温10.3℃。预试... 详细信息

试验旨在研究东北地区秋季饲喂α-酮戊二酸对湖羊精子质量与血浆生化指标的影响,选择体况良好且体重相近的湖羊32只,随机平均分为4组,分别按只补饲0、5、10、20 g/dα-酮戊二酸。试验于8—10月在黑龙江伊春市开展,平均气温10.3℃。预试期7 d,正试期56 d。分别于试验第28、42、56天采集湖羊颈静脉血,评估血浆睾酮、褪黑素、白细胞介素(2、4、6、10)、促肾上腺皮质激素、肿瘤坏死因子-α、丙二醛水平、总抗氧化能力及抗氧化酶活性。采集湖羊精液检测精子活率、精子质膜完整率及精子畸形率。结果表明:α-酮戊二酸对湖羊精子畸形率、血浆睾酮、白细胞介素(2、6、10)水平无显著影响(P>0.05)。每只湖羊补饲20 g/dα-酮戊二酸显著提高了精子活率、精子质膜完整率、血浆褪黑素水平、总抗氧化能力及超氧化物歧化酶、谷胱甘肽过氧化物酶及过氧化氢酶活性(P<0.05),同时显著降低了血浆丙二醛、促肾上腺皮质激素、白细胞介素-4及肿瘤坏死因子-α水平(P<0.05)。说明东北地区秋季每只湖羊补饲20 g/dα-酮戊二酸能够改善精子质量、血浆生殖激素水平、抗氧化能力与免疫指标水平。

关键词： α-酮戊二酸湖羊精子质量抗氧化免疫指标

基于“雨课堂+BOPPPS”科教融合的动物遗传学线上线下混合式课堂实践

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黑龙江动物繁殖 2024年第1期32卷 60-64页

作者：王雪赵帅刘东宇尹国安韩欢胜黑龙江八一农垦大学动物科技学院黑龙江大庆163319

动物遗传学课程一般为涉农高校动物科学专业必修的专业基础课,课程内容多,理论性强,概念抽象。传统的讲授很难提升课堂成效、激发学生的学习兴趣。为进一步提升教学质量,黑龙江八一农垦大学动物遗传育种教学团队进行了教学的改革与创新... 详细信息

动物遗传学课程一般为涉农高校动物科学专业必修的专业基础课,课程内容多,理论性强,概念抽象。传统的讲授很难提升课堂成效、激发学生的学习兴趣。为进一步提升教学质量,黑龙江八一农垦大学动物遗传育种教学团队进行了教学的改革与创新。该教学团队依托华南农业大学线上课程资源,构建了基于“雨课堂+BOPPPS”科教相融合的动物遗传学线上线下混合式教学模式。实践表明,课堂教学改革成效显著,师生互动贯穿“课前—课中—课后”全过程;科教相融重塑课堂教学内容,使理论知识具体生动。综上,基于“雨课堂+BOPPPS”科教融合的动物遗传学线上线下混合式课堂实践有助于提高学生科学素养,激发学生学习兴趣,提升课堂教学质量。

关键词：动物遗传学雨课堂+BOPPPS 科教融合课堂实践线上线下混合教学

High-resolution assessment of retrogressive thaw slump susceptibility in the Qinghai-Tibet Engineering Corridor

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Research in Cold and Arid Regions 2023年第6期15卷 288-294页

作者： guoan yin Jing Luo FuJun Niu MingHao Liu ZeYong Gao TianChun Dong WeiHeng Ni Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China China Railway Qinghai-Tibet Group Co. LtdXiningQinghai 810000China School of Engineering and Science University of Chinese Academy of SciencesBeijing 100049China

Under the rapidly warming climate in the Arctic and high mountain areas,permafrost is thawing,leading to various hazards at a global *** common permafrost hazard termed retrogressive thaw slump(RTS)occurs extensively in ice-rich permafrost *** the spatial and temporal distributive features of RTSs in a changing climate is crucial to assessing the damage to infrastructure and *** this end,we used a machine learning-based model to investigate the environmental factors that could lead to RTS occurrence and create a susceptibility map for RTS along the Qinghai-Tibet Engineering Corridor(QTEC)at a local *** results indicate that extreme summer climate events(e.g.,maximum air temperature and rainfall)contributes the most to the RTS occurrence over the flat areas with fine-grained *** model predicts that 13%(ca.22,948 km^(2))of the QTEC falls into high to very high susceptibility categories under the current climate over the permafrost areas with mean annual ground temperature at 10 m depth ranging from-3 to-1℃.This study provides insights into the impacts of permafrost thaw on the stability of landscape,carbon stock,and infrastructure,and the results are of value for engineering planning and maintenance.

关键词： Retrogressive thaw slumps Thermokarst Permafrost degradation Machine learning

Advances in studies on concrete durability and countermeasures against freezing-thawing effects

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Research in Cold and Arid Regions 2014年第4期6卷 398-408页

作者： WuJian Yan FuJun Niu XianJun Zhang Jing Luo guoan yin State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Key Laboratory of Loess Earthquake Engineering China Earthquake Administration Engineering Management Center of China Railway Corporation

This paper is a meta-analysis of recent domestic and foreign research on freezing-thawing effects on concrete durability. The main theories on the mechanisms of freeze-thaw damage to concrete are introduced： the hydrostatic pressure theory, the osmotic pressure theory, the critical water saturation degree theory, the dual mechanism theory, and the micro-ice-crystal lens model theory. The influence laws of freezing-thawing on the mechanical properties of concrete are summarized, and countermeasures to improve concrete durability in freezing-thawing circumstances are presented. This work provides valuable references for future engineering constructions in cold regions.

关键词： concrete durability freezing-thawing effect mechanical properties countermeasures cold region

Dating of two thermokarst lakes in Beiluhe Basin, Qinghai-Tibetan Plateau

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Research in Cold and Arid Regions 2014年第5期6卷 504-510页

作者： ZhanJu Lin FuJun Niu Jing Luo MingHao Liu guoan yin State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Key Laboratory of Highway Construction & Maintenance Technology in Permafrost Region Ministry of Transport CCCC First Highway Consultants Co.Ltd

Most of the thermokarst lakes are spread appreciably in Beiluhe Basin,Qinghai-Tibet Plateau,China,where ice-rich permafrost *** typical thermokarst lakes with differing area and depth were examined to ascertain their *** obtained lake-bottom samples of 50 cm length from lake BLH-A and 25 cm length from lake *** 137 Cs and 210 Pb and radiocarbon age dating techniques were applied to the 50 cm and 25 cm samples,*** results indicate that the initiation of BLH-A is about 800-900 a B.P.,and approximately 1,450±30 a *** 2,230±30 a *** *** results will provide scientific bases for sedimentological study and thermokarst activity in Beiluhe Basin.

关键词： dating radiocarbon thermokarst lake Beiluhe Basin Qinghai-Tibet Plateau

动物行为与福利学课程思政元素融入的实践与探索

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黑龙江动物繁殖 2024年第2期32卷 63-65页

作者：赵帅王雪张琦刘东宇崔卫国尹国安黑龙江八一农垦大学动物科技学院黑龙江大庆163319

动物行为与福利学是广大农林院校动物医学与动物科学专业的主干课程,但由于其基础教学内容主要来源于欧洲,我国引入之后,无论是结构体系、概念范畴还是理论观点大多是对国外动物行为与福利知识体系的简单套用。将思政元素融入本课程的教... 详细信息

动物行为与福利学是广大农林院校动物医学与动物科学专业的主干课程,但由于其基础教学内容主要来源于欧洲,我国引入之后,无论是结构体系、概念范畴还是理论观点大多是对国外动物行为与福利知识体系的简单套用。将思政元素融入本课程的教学,有利于加快其满足国内教学需要的进程。文章从国家高等教育政策的解读出发,结合思政元素、弘扬我国文化,树立民族自信、讲述我国科学家故事,提高学生科研自豪感、传递知农爱农意识,承担强农兴农使命四个方面探索本课程思政元素的融入,目的在于提高动物行为与福利学课程的教学效果,为引导学生树立正确的价值观提供实践路径。

关键词：畜牧学科课程思政动物行为与福利学实践与探索

In-situ testing study on convection and temperature characteristics of a new crushed-rock slope embankment design in a permafrost region

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Research in Cold and Arid Regions 2014年第4期6卷 378-387页

作者： MingHao Liu FuJun Niu JianHong Fang ZhanJu Lin Jing Luo guoan yin State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Key Laboratory of Highway Construction & Maintenance Technology in Permafrost Region Ministry of TransportCCCC First Highway Consultants Co. Ltd. Qinghai Research and Observation Base Key Laboratory of Highway Construction & Maintenance Technology in Permafrost RegionsMinistry of Transport Qinghai Research Institute of Transportation

For the purpose of enhancing air convection and controlling solar radiation, a new crushed-rock slope embankment design combined with a sun-shade measure is proposed. A newly designed embankment was constructed in the Tuotuohe section of the Qinghai-Tibet Railway and a field-testing experiment was carried out to determine its convection and temperature characteristics. The results show that distinct air convection occurred in the crushed-rock layer of the new embankment, especially in cold seasons, which was enhanced when it flowed upwards along the slope. This preliminarily indicated that the new design of the embankment slope was good for reinforcing air convection in the crushed-rock layer. The frequent fluctuations of the convection speed and the environmental wind speed were in good agreement, suggesting that the convection in the crushed rock primarily came from the ambient wind. It was also preliminarily determined that the new embankment had a better cooling effect and sun-shade effect for decreasing the temperature of the embankment slope compared with a traditional crushed-rock slope embankment, and the mean temperature difference between them was up to 1.7 °C. The mean annual temperature at the bottom boundary of the crushed-rock layer was obviously lower than that at the top boundary, and heat flux calculation showed that the shallow soil beneath the embankment slope was weakly releasing heat, all of which indicated that the new embankment slope design was beneficial to the thermal stability of the embankment. This study is helpful in providing some references for improved engineering design and maintenance of roadbeds in permafrost regions.

关键词： permafrost region railway embankment slope structure air convection characteristics cooling effect

东北地区秋季饲喂赖氨酸锌对湖羊种公羊血浆生化指标与精子质量的影响

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中国畜牧兽医 2024年第2期51卷 558-567页

作者：王赫川李天峰张涵宋宇伦冯赫泽魏姚程烨李用昕董莹莹尹国安郭庆崔卫国李井春黑龙江八一农垦大学动物科技学院大庆163319

[目的]试验旨在研究东北地区秋季饲喂赖氨酸锌对湖羊血浆生化指标与精子质量的影响。[方法]选择体况良好的1~2岁湖羊种公羊32只随机平均分为4组,分别补饲0、25、50、100 mg/d赖氨酸锌。试验于2022年8月至2022年10月在黑龙江伊春开展,平... 详细信息

[目的]试验旨在研究东北地区秋季饲喂赖氨酸锌对湖羊血浆生化指标与精子质量的影响。[方法]选择体况良好的1~2岁湖羊种公羊32只随机平均分为4组,分别补饲0、25、50、100 mg/d赖氨酸锌。试验于2022年8月至2022年10月在黑龙江伊春开展,平均气温10.3℃。试验预试期7 d,正试期56 d。分别于试验第28、42及56天采集湖羊颈静脉血,测定血浆睾酮、褪黑素、白细胞介素-2、白细胞介素-4、白细胞介素-6、白细胞介素-10、促肾上腺皮质激素和肿瘤坏死因子-α水平,以及血浆总抗氧化能力、过氧化氢酶、超氧化物歧化酶、谷胱甘肽过氧化物酶活性及丙二醛水平。采集湖羊精液测定精子活率、质膜完整率及畸形率。[结果]第28天时50 mg/d组湖羊褪黑素水平显著高于0及100 mg/d组(P<0.05),总抗氧化能力显著高于0 mg/d组(P<0.05),白细胞介素-4水平显著低于25 mg/d组(P<0.05),白细胞介素-10水平显著低于0 mg/d组(P<0.05)。第42天时50 mg/d组湖羊超氧化物歧化酶活性显著高于0 mg/d组(P<0.05),白细胞介素-4水平显著低于其他各组(P<0.05),促肾上腺皮质激素水平显著低于0及100 mg/d组(P<0.05)。第56天时50 mg/d组湖羊精子质膜完整率显著高于0 mg/d组(P<0.05),超氧化物歧化酶活性显著高于0 mg/d组(P<0.05),白细胞介素-4水平显著低于0及100 mg/d组(P<0.05)。[结论]补饲赖氨酸锌能够改善东北地区秋季湖羊种公羊血浆生殖激素水平、抗氧化能力、免疫指标水平与精子质量,建议补饲量为50 mg/d。

关键词：赖氨酸锌湖羊精子质量抗氧化免疫

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Geomorphology-oriented theoretical framework and construction method for value-added DEM

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Journal of Geographical Sciences 2024年第1期34卷 165-184页

作者： ZHANG Haiping TANG guoan XIONG Liyang YANG Xin LI Fayuan Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023China School of Geography Nanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Digital elevation model(DEM)plays a fundamental role in the study of the earth system by expressing surface configuration,understanding surface process,and revealing surface *** is widely used in analysis and modeling in the field of ***,traditional DEM has the defect of single attribute,which is difficult to support the research in earth system science oriented to geoscience process and mechanism ***,realizing the value-added data model on the basis of traditional DEM is necessary to serve digital elevation modeling and terrain analysis under the background of a new geomorphology research paradigm and earth observation technology.A theoretical framework for value-added DEM that mainly includes concept,connotation,content,and categories,is constructed in this *** relationship between different types of value-added DEMs as well as the research significance and application category of this theoretical framework are also *** following are different methods of value-added DEMs:(1)value-added methods of DEM space and time dimensions that emphasize the integration of the ground and underground as well as coupling of time and space,(2)attribute-based value-added methods composed of material(including underground,surface,and ground)and morphological properties,and(3)value-added methods of features and physical elements that consider geographical objects and landform features formed by natural processes and artificial *** digital terrace,slope,and watershed models are used as examples to illustrate application scenarios of the three kinds of value-added *** study aims to improve expression methods of DEMs under the background of new surveying and mapping technologies by adding value to the DEM at three levels of dimensions,attributes,and elements as well as support knowledge-driven digital geomorphological analysis in the era of big data.

关键词： spatial data model value-added DEM digital terrain analysis geomorphological ontology geomorphology