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Effects of Melatonin on Spermatozoa Activity and Associated Mechanisms in Heat-Stressed Rats

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Journal of Clinical and Nursing Research 2024年第7期8卷 97-111页

作者： kai Tan Wenduo Chen Jing Huang Jianzhi Pan School of Life Sciences China Jiliang UniversityHangzhou 310018Zhejiang ProvinceChina College of Animal Science and Technology Zhejiang Agriculture and Forestry UniversityHangzhou 311300Zhejiang ProvinceChina Zhejiang Academy of Agriculture Science Virology and Biotechnology InstituteHangzhou 310021Zhejiang ProvinceChina

In animals,heat stress(HS)disrupts spermatogenesis,reducing sperm quality and,in severe cases,potentially inducing the loss of male reproductive *** confers significant resistance to oxidative stress and apoptosis;however,its specific effects on rat spermatocytes and the mechanism underlying its anti-HS effects remain inadequately ***,this study aimed to analyze the effects of melatonin at different concentrations on sperm cell activity in heat-stressed *** heat stress injury,sperm viability and density assay,sperm plasma membrane integrity analysis,and oxidative stress assay of testicular tissue were *** results revealed that HS caused sperm cell ***,the intraperitoneal injection of melatonin effectively improved spermatozoa quality,and a dose of 1 mM significantly alleviated the HS-induced ***,HS increased the levels of oxidative and endoplasmic reticulum(ES)stress in rat testicular tissues,inducing germ cell apoptosis and pathological ***,melatonin treatment improved sperm cell viability and density,inhibited germ cell apoptosis,and reduced oxidative and ES stress ***,melatonin effectively reduced the adverse effects of HS on rat sperm cells,and an intraperitoneal injection of 1 mM(0.6966 mg)melatonin facilitated the normal production of ***,its mechanism may involve reduced ES and oxidative stress levels in testicular tissues,increased expression of the anti-apoptotic protein Bcl-2,and inhibition of germ cell apoptosis.

关键词： Melatonin Rat Spermatocyte Spermatogenesis Antioxidant

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西藏退化草地植被和土壤特征及其关系

环境科学 2024年第9期45卷 5341-5350页

作者：李晴婉古晋锴李庆琳李婉池向生建唐国勇中国林业科学研究院高原林业研究所昆明650233 南京林业大学风景园林学院南京210037 云南大学国际河流与生态安全研究院昆明650504

为探究区域尺度上西藏草地退化特征,收集西藏第二次草原普查成果中草地退化数据及国家青藏高原科学数据中心12个植被和土壤参数数据,利用ArcMap在栅格数据上随机选取10000个样点(剔除非草地、沙化和盐碱化草地数据,剩余7949个有效样点)... 详细信息

为探究区域尺度上西藏草地退化特征,收集西藏第二次草原普查成果中草地退化数据及国家青藏高原科学数据中心12个植被和土壤参数数据,利用ArcMap在栅格数据上随机选取10000个样点(剔除非草地、沙化和盐碱化草地数据,剩余7949个有效样点),采取多值提取到点的方法提取每个样点退化和参数数据,分析西藏退化草地植被和土壤特征及其关系,并基于以上指标进行随机森林建模来预测草地生态系统变化趋势.结果表明:①西藏草地主要以高寒草原类和高寒草甸类为主,分别占有效样点45.83%和41.15%;②随草地退化程度加剧,在17个草地类型中,草地型种类的数量逐渐下降,以紫花针茅(Stipa purpurea)和青藏苔草(Carex moorcroftii)等为优势物种的草地型占比下降,杂类草和金露梅(Dasiphora fruticosa)等占比增加;③随退化程度加剧,植被指标普遍呈下降趋势,土壤全氮、全磷、全钾和有机碳降低,土壤pH和容重升高,土壤水分变化不明显;④土壤水分、全氮、全磷、全钾、有机碳、植被覆盖度、植被净初级生产力、归一化植被指数、地上生物量和生物多样性生境指数之间均呈正相关关系,但与土壤pH和容重呈负相关关系,且随退化程度加剧,各指标之间的相关系数降低;⑤随机森林模拟结果表明,在退化过程中土壤容重和生物多样性生境指数的贡献率均超过12%,模型预测准确率达到78%.研究揭示西藏草地退化主要与土壤容重和生物多样性生境指数密切相关,即土壤容重越大或生物多样性生境指数越小,草地退化程度可能越重,可为以后草地保护与管理提供科学依据.

关键词：西藏草地退化植被指标土壤理化性质相关性随机森林

Annual and Monthly Variations in Litter Macronutrients of Three Subalpine Forests in Western China

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Pedosphere 2006年第6期16卷 788-798页

作者： YANG Wan-Qin WANG kai-Yun S. KELLOMAKI ZHANG Jian Faculty of forestry Sichuan Agricultural University Ya＇an 625014 （China） Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041 （China） university of Joensuu Faculty of Forestry P.O. Box 111 FIN-80101 （Finland）

Macronutrients （N, P, K, Ca, Mg, and S） in litter of three primarily spruce （Picea purpurea Masters）（SF）, fir （Abies faxoniana Rehder ＆ E. H. Wilson）（FF）, and birch （Betula platyphylla Sukaczev）（BF） subalpine forests in western China were measured to understand the monthly variations in litter nutrient concentrations and annual and monthly nutrient returns via litteffall. Nutrient concentration in litter showed the rank order of Ca 〉 N 〉 Mg 〉 K 〉 S 〉 P. Monthly variations in nutrient concentrations were greater in leaf litter （LL） than other litter components. The highest and lowest concentrations of N, P, K, and S in LL were found in the growing season and the nongrowing season, respectively, but Ca and Mg were the opposite. Nutrient returns via litterfall showed a marked monthly pattern with a major peak in October and one or two small peaks in February and/or May, varying with the element and stand type, but no marked monthly variations in nutrient returns via woody litter, reproductive litter, except in May for the BF, and moss litter. Not only litter production but also nutrient concentration controlled the annual nutrient return and the monthly nutrient return pattern. The monthly patterns of the nutrient concentration and return were of ecological importance for nutrient cycling and plant growth in the subalpine forest ecosystems.

关键词： litterfall macronutrient return monthly variation nutrient concentration subalpine forest

Effects of Fungi Fusarium sp. to Rhizosphere Soil and Physiological Characteristics of Camellia oleifera Abel.

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Asian Agricultural Research 2024年第2期16卷 22-30页

作者： Xuejin WANG kai YAN Tianhua YU Zhannan YANG Shiqiong LUO Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment of Guizhou Province Guizhou Normal UniversityGuiyang 550025China School of Life Science Guizhou Normal UniversityGuiyang 550025China Liupanshui Normal university Liupanshui 553004China

[Objectives]To study the effects of fungi Fusarium *** rhizosphere soil and physiological characteristics of Camellia oleifera Abel.[Methods]We investigated the effects of Fusarium *** rhizosphere soil nutrient element content and metabolites of *** was inoculated with the suspension of Fusarium *** pot experiments and ammonium-N,available phosphorus,available potassi-um,organic matter,enzymes and pH of rhizosphere soil,MDA content,activity of SOD,POD of *** leaves were analyzed.[Results]Fusarium *** significantly inhibited soil enzyme activities and significantly reduced available phosphorus content,especially for phospha-tase and *** enzyme activities in *** tissues showed that Fusarium *** significantly increased MDA and SOD enzyme activities and decreased POD enzyme ***,SOD enzyme activity was elevated by 53.86%compared with the CK *** addition,analysis of the content of major metabolites in *** leaves showed that Fusarium *** significantly reduced the content of total flavonoids,quercetin,isoquercitrin and isoquercitrin in *** leaves by 7.80%,50.00%and 75.90%,respectively.[Conclusions]Our results are an important step which showed strong resistance of *** and can give a novel insight for researches on the effects in the rhizosphere soil enzyme,soil nutrient elements and metabolites of *** under the Fusarium ***.

关键词： Camellia oleifera Abel. Fusarium sp. Antioxidant enzymes Soil enzymes Soil quality

不同原料对水下激光直接金属沉积修复HSLA钢微观组织和力学性能的影响

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表面工程与再制造 2024年第3期24卷 63-64页

作者： Zhandong Wang Mingzhi Chen kai Zhao Rui Li Le Zong Shengbiao Zhang Guifang Sun College of Mechanical and Electronic Engineering Nanjing Forestry University Nanjing Jiangsu 210037 PR China School of Mechanical Engineering Southeast University Nanjing Jiangsu 211189 PR China National Deep Sea Center Ministry of Natural Resources Qingdao Shandong 266237 PR China Department of Mechanical and Industrial Engineering University of Massachusetts Amherst MA 01003 USA

水下激光直接金属沉积(UDMD)技术在海洋受损结构的现场修复方面显示出巨大的潜力。本研究针对柔性原料替代的可能性,采用两种不同性能的粉末对提前准备好的HSLA钢板进行UDMD修复。系统研究了合金成分和UDMD工艺对修复性能的综合影响,包... 详细信息

水下激光直接金属沉积(UDMD)技术在海洋受损结构的现场修复方面显示出巨大的潜力。本研究针对柔性原料替代的可能性,采用两种不同性能的粉末对提前准备好的HSLA钢板进行UDMD修复。系统研究了合金成分和UDMD工艺对修复性能的综合影响,包括微观组织、力学性能和腐蚀行为。

关键词： HSLA钢直接金属沉积合金成分微观组织组织和力学性能水下激光现场修复原料替代

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多元化食物供给体系的概念界定与构建对策

中国农业大学学报 2024年第10期29卷 72-84页

作者：杨鑫刘凯中国社会科学院农村发展研究所北京100732 商务部国际贸易经济合作研究院北京100710

多元化食物供给体系的概念复杂且尚没有达成一致,容易引发中国食物政策实践偏差。为提升大食物观下的粮食安全治理水平,基于归纳总结多元化食物供给体系政策缘起、不同食物类型的政策优先序、“多元化”的四重内涵,本研究对多元化食物... 详细信息

多元化食物供给体系的概念复杂且尚没有达成一致,容易引发中国食物政策实践偏差。为提升大食物观下的粮食安全治理水平,基于归纳总结多元化食物供给体系政策缘起、不同食物类型的政策优先序、“多元化”的四重内涵,本研究对多元化食物供给体系概念进行了界定,即在确保食物供给保障优先序的治理体系下,为满足日益多元化的食物消费需求,通过有序利用耕地资源、开发利用各类国土资源、促进各类食物生产技术共同进步、丰富食物进口渠道等方式,拓展食物来源的复杂系统。本研究通过分析多元化食物供给体系构建的挑战,提出其构建对策,包括同步提升粮食综合生产能力和耕地管理精细化程度、降低林牧渔业在非耕地生产的边际成本、探索差异化农业产业发展模式、调整大豆玉米国际供应链格局。

关键词：多元化食物供给体系大食物观粮食安全治理食物系统

Identification and distribution of 13003 landslides in the northwest margin of Qinghai-Tibet Plateau based on human-computer interaction remote sensing interpretation

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China Geology 2024年第2期7卷 171-187页

作者： Wei Wang Yuan-dong Huang Chong Xu Xiao-yi Shao Lei Li Li-ye Feng Hui-ran Gao Yu-long Cui Shuai Wu Zhi-qiang Yang kai Ma National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Key Laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of Chin12eijing 100085China School of Emergency Management Science and Engineering University of Chinese Academy of SciencesBeijing 100049China School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China School of Civil Engineering and Architecture Anhui University of Science and TechnologyHuainan 232001China No.3 Bureau of China Metallurgical Geology Bureau Taiyuan 030031China

The periphery of the Qinghai-Tibet Plateau is renowned for its susceptibility to ***,the northwestern margin of this region,characterised by limited human activities and challenging transportation,remains insufficiently explored concerning landslide occurrence and *** the planning and construction of the Xinjiang-Tibet Railway,a comprehensive investigation into disastrous landslides in this area is essential for effective disaster preparedness and mitigation *** using the human-computer interaction interpretation approach,the authors established a landslide database encompassing 13003 landslides,collectively spanning an area of 3351.24 km^(2)(36°N-40°N,73°E-78°E).The database incorporates diverse topographical and environmental parameters,including regional elevation,slope angle,slope aspect,distance to faults,distance to roads,distance to rivers,annual precipitation,and *** statistical characteristics of number and area of landslides,landslide number density(LND),and landslide area percentage(LAP)are *** authors found that a predominant concentration of landslide origins within high slope angle regions,with the highest incidence observed in intervals characterised by average slopes of 20°to 30°,maximum slope angle above 80°,along with orientations towards the north(N),northeast(NE),and southwest(SW).Additionally,elevations above 4.5 km,distance to rivers below 1 km,rainfall between 20-30 mm and 30-40 mm emerge as particularly susceptible to landslide *** study area’s geological composition primarily comprises Mesozoic and Upper Paleozoic *** fault and human engineering activities have different degrees of influence on landslide ***,the significance of the landslide database,the relationship between landslide distribution and environmental factors,and the geometric and morphological characteristics of landslides are *** landslide H/L ratios in the study area are

关键词： Landslides Human-computer interaction interpretation Landslide database Spatial distribution Earthquake Rainfall Human engineering activity Qinghai-Tibet Plateau Geological hazards survey engineering

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新西兰国家公园社区共管模式发展经验及启示

世界林业研究 2024年第4期37卷 105-110页

作者：周雯佳陈凯北京林业大学经济管理学院北京100083

在我国国家公园体制建设的背景下,国家公园管理面临着如何平衡自然保护与当地社区权益的复杂挑战。尤其是在少数民族众多的区域,原住民和当地社区的参与不仅关乎到生态保护的成效,也涉及到当地民族和传统文化的保护和传承。新西兰国家... 详细信息

在我国国家公园体制建设的背景下,国家公园管理面临着如何平衡自然保护与当地社区权益的复杂挑战。尤其是在少数民族众多的区域,原住民和当地社区的参与不仅关乎到生态保护的成效,也涉及到当地民族和传统文化的保护和传承。新西兰国家公园的原住民共管机制为探索我国国家公园的社区管理制度提供了一个独特的参考。文中将新西兰国家公园社区共管模式的发展过程分为3个阶段,从法律框架保障、多方协同组织和社区参与机制3个方面总结其社区共管的发展经验,并结合中国国情和地方特色提出了对我国国家公园社区共管实践的建议。

关键词：国家公园社区共管社区参与可持续管理新西兰

Overlooked uneven progress across sustainable development goals at the global scale: Challenges and opportunities

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The Innovation 2024年第2期5卷 42-50页

作者： Yali Liu Jianqing Du Yanfen Wang Xiaoyong Cui Jichang Dong Pan Gu Yanbin Hao kai Xue Hongbo Duan Anquan Xia Yi Hu Zhi Dong Bingfang Wu Jüurgen P.Kropp Bojie Fu School of Grassland Science Beijing Forestry UniversityBeijing 100083China Beijing Yanshan Earth Critical Zone National Research Station University of Chinese Academy of SciencesBeijing 101408China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Tibetan Plateau Earth System Environment and ResourcesChinese Academy of SciencesBeijing 100101China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China School of Humanities University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810001China School of Innovation and Entrepreneurship University of Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100101China Potsdam Institute for Climate Impact Research 14412 PotsdamGermany Institute for Environmental Science and Geography University of Potsdam14412 PotsdamGermany State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Differences in progress across sustainable development goals(SDGs)are widespread globally;meanwhile,the rising call for prioritizing specific SDGs may exacerbate such ***,how these progress differences would influence global sustainable development has been long ***,we present the first quantitative assessment of SDGs’progress differences globally by adopting the SDGs progress evenness *** results highlight that the uneven progress across SDGs has been a hindrance to sustainable development because(1)it is strongly associated with many public health risks(e.g.,air pollution),social inequalities(e.g.,gender inequality,modern slavery,wealth gap),and a reduction in life expectancy;(2)it is also associated with deforestation and habitat loss in terrestrial and marine ecosystems,increasing the challenges related to biodiversity conservation;(3)most countries with low average SDGs performance show lower progress evenness,which further hinders their fulfillment of SDGs;and(4)many countries with high average SDGs performance also showcase stagnation or even retrogression in progress evenness,which is partly ascribed to the antagonism between climate actions and other *** findings highlight that while setting SDGs priorities may be more realistic under the constraints of multiple global stressors,caution must be exercised to avoid new problems from intensifying uneven progress across ***,our study reveals that the urgent needs regarding SDGs of different regions seem complementary,emphasizing that regional collaborations(e.g.,demand-oriented carbon trading between SDGs poorly performed and well-performed countries)may promote sustainable development achievements at the global scale.

关键词： globally priori inequality