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Spatiotemporal Evolution of Ecological Quality in Alpine Freshwater Lake Nature Reserves in the Past 20 Years
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作者 Denghong HUANG Chenli LIAO +1 位作者 Zhenzhen ZHANG Jintong REN 《Meteorological and Environmental Research》 2024年第2期29-36,共8页
The Caohai Nature Reserve is one of the three major plateau freshwater lakes in China.Since the 1950s,human activities such as land reclamation and population relocation have greatly damaged Caohai.A rapid evaluation ... The Caohai Nature Reserve is one of the three major plateau freshwater lakes in China.Since the 1950s,human activities such as land reclamation and population relocation have greatly damaged Caohai.A rapid evaluation of the spatiotemporal evolution trend of the ecological quality of the Caohai Nature Reserve is significant for the maintenance and construction of the ecosystem in this area.The research is based on the Google Earth Engine(GEE)remote sensing cloud computing platform.Landsat TM/OLI images from May to October in five time periods:2000-2002,2004-2006,2009-2011,2014-2016,and 2019-2021 were obtained to reconstruct the optimal cloud image set by averaging the images in each time period.By constructing four ecological indicators:Greenness(NDVI),Wetness(Wet),Hotness(LST),and Dryness(NDBSI),and using Principal Component Analysis(PCA)method to obtain the Remote Sensing Ecological Index(RSEI)for the corresponding years,the spatiotemporal variation of ecological quality in the Caohai Nature Reserve over 20 years was analyzed.The results indicate:①the mean value of RSEI increased from 0.460 in 2000-2002 to 0.772 in 2019-2021,a 67.83%increase,indicating a significant improvement in the ecological quality of the reserve over the 20 years;②from the perspective of functional zoning of the Caohai Nature Reserve,the ecological quality of the core area showed a degrading trend,while the ecological quality of the buffer zone and experimental zone significantly improved;③with the implementation of ecological restoration projects,the ecological quality of the reserve gradually recovered and improved from 2014 to 2021.The trend of RSEI value changes is well correlated with human interventions,indicating that the PCA-based RSEI model can be effectively used for ecological quality assessment in lake areas. 展开更多
关键词 Ecological restoration Ecological quality Remote sensing ecological index Google Earth Engine Caohai Nature reserve
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Protection and Quality Control of Wild Chinese Herbal Medicine Resources in Nature Reserves by Taking Longyuwan Scenic Spot Within Funiu Mountain Nature Reserve as an Example 被引量:1
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作者 Wang Shao-hui Liu Meng-na +4 位作者 Wang Xu Zhang Ya-chen Han Yi-wen Zhang Ce Liu Tong-xiang 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第3期90-96,共7页
This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Thr... This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Through the combination of three methods including literature review, visiting and investigational studies, and field surveys, the data of investigation, collection and collation were analyzed. According to data of surveys, collection and collation, problems related to the protection of wild Chinese herbal medicine resources faced by Longyuwan Scenic Spot within Funiu Mountain Nature Reserve were also analyzed and protection strategies and quality control of wild Chinese herbal medicine resources in this nature reserve were discussed. It was expected that the results would provide important scientific references for the sustainable development, protection and quality control of wild Chinese herbal medicine resources within nature reserves. 展开更多
关键词 nature reserve wild Chinese herbal medicine resource PROTECTION quality control
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Field mold stress induced catabolism of storage reserves in soybean seed and the resulting deterioration of seed quality in the field 被引量:1
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作者 DENG Jun-cai LI Xiao-man +15 位作者 XIAO Xin-li WU Hai-jun YANG Cai-qiong LONG Xi-yang ZHANG Qi-hui Nasir IQBAL WANG Xiao-chun YONG Tai-wen DU Jun-bo YANG Feng LIU Wei-guo ZHANG Jing WU Xiao-ling WU Yu-shan YANG Wen-yu LIU Jiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第2期336-350,共15页
Excessive rainfall provides a favorable condition for field mold infection of plants, which triggers field mold(FM) stress. If FM stress occurs during the late maturation stage of soybean seed, it negatively affects s... Excessive rainfall provides a favorable condition for field mold infection of plants, which triggers field mold(FM) stress. If FM stress occurs during the late maturation stage of soybean seed, it negatively affects seed yield and quality. To investigate the responses of soybean seed against FM stress and identify the underlying biochemical pathways involved, a greenhouse was equipped with an artificial rain producing system to allow the induction of mold growth on soybean seed. The induced quality changes and stress responses were revealed on the levels of both transcriptome and metabolome. The results showed that soybean seeds produced under FM stress conditions had an abnormal and inferior appearance, and also contained less storage reserves, such as protein and polysaccharide. Transcriptional analysis demonstrated that genes involved in amino acid metabolism, glycolysis, tricarboxylic acid, β-oxidation of fatty acids, and isoflavone biosynthesis were induced by FM stress. These results were supported by a multiple metabolic analysis which exhibited increases in the concentrations of a variety of amino acids, sugars, organic acids, and isoflavones, as well as reductions of several fatty acids. Reprogramming of these metabolic pathways mobilized and consumed stored protein, sugar and fatty acid reserves in the soybean seed in order to meet the energy and substrate demand on the defense system, but led to deterioration of seed quality. In general, FM stress induced catabolism of storage reserves and diminished the quality of soybean seed in the field. This study provides a more profound insight into seed deterioration caused by FM stress. 展开更多
关键词 seed deterioration seed quality primary metabolism storage reserves resistance
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Spatiotemporal variations of ecosystem services and driving factors in the Tianchi Bogda Peak Natural Reserve of Xinjiang,China
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作者 ZHU Haiqiang WANG Jinlong +2 位作者 TANG Junhu DING Zhaolong GONG Lu 《Journal of Arid Land》 SCIE CSCD 2024年第6期816-833,共18页
Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,i... Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,is an important ecological barrier area in the temperate arid zone.The evaluation of its important ecosystem services is of great significance to improve the management level and ecological protection efficiency of the reserve.In the present study,we assessed the spatiotemporal variations of four ecosystem services(including net primary productivity(NPP),water yield,soil conservation,and habitat quality)in the TBPNR from 2000 to 2020 based on the environmental and social data using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.In addition,the coldspot and hotspot areas of ecosystem services were identified by hotspot analysis,and the trade-off and synergistic relationships between ecosystem services were analyzed using factor analysis in a geographic detector.During the study period,NPP and soil conservation values in the reserve increased by 48.20%and 25.56%,respectively;conversely,water yield decreased by 16.56%,and there was no significant change in habitat quality.Spatially,both NPP and habitat quality values were higher in the northern part and lower in the southern part,whereas water yield showed an opposite trend.Correlation analysis revealed that NPP showed a synergistic relationship with habitat quality and soil conservation,and exhibited a trade-off relationship with water yield.Water yield and habitat quality also had a trade-off relationship.NPP and habitat quality were affected by annual average temperature and Normalized Difference Vegetation Index(NDVI),respectively,while water yield and soil conservation were more affected by digital elevation model(DEM).Therefore,attention should be paid to the spatial distribution and dynamics of trade-off and synergistic relationships between ecosystem services in future ecological management.The findings of the present study provide a reference that could facilitate the sustainable utilization of ecosystem services in the typical fragile areas of Northwest China. 展开更多
关键词 net primary productivity(NPP) water yield soil conservation habitat quality Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model geographic detector Tianchi Bogda Peak Natural reserve
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Daily Generation Strategies with Consideration of Electricity Contract and Spinning Reserve
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作者 蒋东荣 李群湛 《Journal of Southwest Jiaotong University(English Edition)》 2008年第1期30-36,共7页
When programming the daily generation strategies, power plants consider not only the competitive bids in spot market and the original purchase contracts with distribution companies or users, but also the spinning rese... When programming the daily generation strategies, power plants consider not only the competitive bids in spot market and the original purchase contracts with distribution companies or users, but also the spinning reserve. Aiming at this goal, the paper puts forward a daily generating model, which is a nonlinear programming model containing integral and continous variables, to coordinate the power volumes of competitive bids, contract and the spinning reserve of power plants and thus to maximize their profits. Then, the model is simplified to ease its solving process, and solved by priority ranking method based on efficiency and quadratic programming. The simulation result of a case study shows that the proposed scheme is reasonable and practicable. 展开更多
关键词 Electricity market contract Spinning reserve Priority ranking method Quadratic programming
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Cognitive and Brain Reserve (CBR) Tools to Reduce the Risk of Dementia and Alzheimer
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作者 Mosad Zineldin 《Advances in Alzheimer's Disease》 2018年第4期93-102,共10页
The study was performed to examine and assess the impact of the education, occupation and leisure time on building brain and cognitive reserves (CBR). A cross sectional study of 132 persons at age between 40 to 70 yea... The study was performed to examine and assess the impact of the education, occupation and leisure time on building brain and cognitive reserves (CBR). A cross sectional study of 132 persons at age between 40 to 70 years old has been conducted. A structured questionnaire covering multiple constructs was used to collect the data. Multivariate regression results show that the three independent variables (LE, OC and ED) were statistically significant in the models with CBR as dependent variable. Leisure time and activities (LE) make the strongest unique contribution (0.683) followed by occupation (0.261) and the weak contribution of the education (0.198) to explain the dependent variable cognitive and brain reserve (CBR). The Brain and Cognitive Reserve hypothesesassumes that a rich intellectual measures and abilities a person have during her/his life enable this person to cope with difficult cognitive tasks and social events in life. 展开更多
关键词 COGNITIVE reserve BRAIN reserve DEMENTIA ALZHEIMER quality quality of Life Neurological BRAIN
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Multi-parameter quantitative assessment of 3D geological models for complex fault-block oil reservoirs 被引量:3
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作者 TAN Xuequn LIU Yunyan +3 位作者 ZHOU Xiaozhou LIU JiANDang ZHENG Rongchen JIA Chao 《Petroleum Exploration and Development》 2019年第1期194-204,共11页
In the field of 3 D geologic modeling, researchers often pay more attention to modeling methods and workflows, but neglect the quantitative evaluation of models. If the evaluation is narrowed to the same reservoir typ... In the field of 3 D geologic modeling, researchers often pay more attention to modeling methods and workflows, but neglect the quantitative evaluation of models. If the evaluation is narrowed to the same reservoir type, the comparability and practicality of quantitative assessment will be emerging. The evaluation system should include three parts: data verification, geological understanding and process check. Data verification mainly involves testing the accuracy of local prediction with actual data, and geological understanding is to examine whether the global estimation honors geological principles and prior insights. Process check is also indispensable to avoid occasionality. To this end, we produced a set of assessment criteria, taking complex fault-block sandstone oil reservoir as an example. To be specific, thirteen characteristic parameters were totally selected, setting weights according to their rated importance, formulating three-level evaluation standards in a centesimal system for each characteristic parameter, and obtaining the final assessment based on the cumulative score. The results indicate that such evaluation can not only access the quality of the model objectively and comprehensively, but also identify the aspects in need of improvement through the deduction items. 展开更多
关键词 reservOIR characterization GEOLOGICAL modeling quality evaluation CHARACTERISTIC parameter reserveS estimation faultblock oil reservOIR
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Empirical Study on the Benefit Increase of New Contract Farming 1+3+X Model 被引量:1
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作者 Jiaohu YANG Zhong CHENG +1 位作者 Hao ZHOU Peter ZHANG 《Asian Agricultural Research》 2020年第4期7-13,33,共8页
For a long time,the development model of traditional rice planting industry has been single,linear,and focusing on production first and then market.However,with the low price of rice,such problems as slow technologica... For a long time,the development model of traditional rice planting industry has been single,linear,and focusing on production first and then market.However,with the low price of rice,such problems as slow technological upgrading,meager profits,and unstable rice quality in the primary industry planting units and farmers have become increasingly prominent.The integration and development of the rural primary,secondary,and tertiary industries and industrial integration have the same root.They are integrated industrial development based on technological or model innovation,vertical and horizontal integration.Three agricultural leading companies(Nanjing Tianwei Agricultural Technology Co.,Ltd.,Nanjing CHYKINGYOUNG Biological Technology Co.,Ltd.,and Jiangsu Jingshan Eco-organic Agriculture Co.,Ltd.)established an industrialization complex,and used their respective technical,operational,and market advantages to integrate and form a rice contract farming 1+3+X model.This model effectively integrates scattered rice planting,rice processing,and rice sales in Nanjing City of Jiangsu Province,and Chuzhou City of Anhui Province,and unifies planting regulations and supply of production materials,safeguards the supply of green and high-quality rice and realizes high quality and high price.In addition,it integrates farmers into the entire industrial chain of contract farming,summons up the production enthusiasm of farmers and greatly increases their income from planting production. 展开更多
关键词 Integration of primary secondary and TERTIARY industries contract FARMING Green and high quality Benefit INCREASE from multiple dimensions 1+3+X MODEL Rice PLANTING Menghu Intelligent
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Resource management with borrowing from reservation for cognitive networks
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作者 李丹丹 Zhang Runtong +1 位作者 Shang Xiaopu Chen Ying 《High Technology Letters》 EI CAS 2013年第3期301-308,共8页
Resource reservation is an effective measure to ensure end-to-end quality of service (QoS), however, the burstyness of the traffic makes the reservation idle some time, and forms a waste of re- sources. Based on the... Resource reservation is an effective measure to ensure end-to-end quality of service (QoS), however, the burstyness of the traffic makes the reservation idle some time, and forms a waste of re- sources. Based on the analysis of active queue management (AQM) of DiffServ network, we propose a resource management scheme, which allows borrowing resources from unused reservation, accord- ing to the characteristics and advantages of cognitive networks. First, some nodes reserve certain proportion capacity for some special services (for instance, some services pay additional money) to guarantee the priority of these applications. Then resources are assigned according to the different parameters of services. If the available resource can not meet the requirements of new services, real- time ones are admitted with higher priority and allow borrowing the unused reservation from other nodes appropriately. Simulations show that, the proposed scheme has good performance at network resource utilization, the admission rate of new aDolications and OoS of users. 展开更多
关键词 cognitive networks resource reservation adaptive borrowing quality of service( Qos
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青年强则国强:青年人口学前瞻与优化青年人口发展 被引量:3
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作者 穆光宗 侯梦舜 +3 位作者 尹书山 穆昱含 李旺 张雨琪 《中国农业大学学报(社会科学版)》 CSSCI 北大核心 2024年第2期5-28,共24页
从当年梁启超发出历史呼号“少年强则国强”、李大钊提出“青春中华之创造”到如今党的二十大报告发出时代强音“青年强,则国家强”,显示了一脉相承的青少年与国家发展联系紧密的认识逻辑。本文回顾和界定了青年及青年人口学的内涵,认... 从当年梁启超发出历史呼号“少年强则国强”、李大钊提出“青春中华之创造”到如今党的二十大报告发出时代强音“青年强,则国家强”,显示了一脉相承的青少年与国家发展联系紧密的认识逻辑。本文回顾和界定了青年及青年人口学的内涵,认为青年可定义为“风险型人口”和“资源型人口”两大类,继而讨论了“青年强”的三重含义,即青年人口储备充足、青年人口素质卓越和青年人口红利丰厚,充分诠释了“青年强,则国家强”时代命题的深刻内涵。概言之,人尽其才则“青年强”,才尽其用则“国家强”。本文从国际比较的视角阐述了我国青年人口发展面临的问题和挑战,突出表现为:中国未来青年人口数量将长期处于缩减状态;青年人口的科学文化素质、身体健康素质和思想素质都有待“提质增效”;就业不充分,青年人口红利没有被充分释放。因此,要优化青年人口发展、进一步增强青年力量,采取相应的对策来强化青年人口储备、优化青年人口素质、极化青年人口红利、激发全人口活力。在人口负增长时代,建设适宜青年生存与发展的青年友好型社会极为必要,把解决青年问题作为解决低生育率等社会人口问题的重要突破口迫在眉睫。 展开更多
关键词 青年 青年人口学 少子化 青年人口储备 青年人口红利 健康储蓄 青年高质量发展
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苍山洱海国家级自然保护区森林资源动态
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作者 李亚楠 王生 +2 位作者 王有兵 姜健发 胡昌平 《大理大学学报》 2024年第6期31-37,共7页
目的:了解云南苍山洱海国家级自然保护区(以下简称“保护区”)森林资源近20年的动态变化特征,为保护区编制经营管理方案提供指导。方法:以2005、2015年森林资源调查矢量数据、2021年森林、草原、湿地监测数据、第三次全国土地调查数据... 目的:了解云南苍山洱海国家级自然保护区(以下简称“保护区”)森林资源近20年的动态变化特征,为保护区编制经营管理方案提供指导。方法:以2005、2015年森林资源调查矢量数据、2021年森林、草原、湿地监测数据、第三次全国土地调查数据为基础数据,基于GIS技术,分析保护区森林资源动态。结果:保护区土地利用类型中,有林地面积最大,并逐年增加;林地中,3个调查年度均以有林地和灌木林地为主,面积占保护区总面积的60.82%以上;保护区森林覆盖率2005—2015年间逐年增加,2015—2021年间增加值逐步趋于稳定;蓄积量以有林地蓄积为主,并逐年增加;乔木林地面积和蓄积量以栎类、云南松、华山松和苍山冷杉为主,且逐年增加;乔木林地中幼龄林、中龄林、近熟林和成熟林比重相对均衡,过熟林面积较少;各年度郁闭度等级均以中为主,且郁闭度等级为中和密的乔木林地面积和蓄积量均逐年增加。结论:保护区森林质量和生态防护功能逐年提高,后期森林资源管理以增加栎类等阔叶林为主。 展开更多
关键词 森林资源 动态分析 森林质量 苍山洱海国家级自然保护区
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基于柔性契约的应急物资政企联合储备定价博弈模型
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作者 王喆 单红颜 +1 位作者 陶梦琪 罗梦柯 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第9期20-28,共9页
为提高突发事件应急物资保障能力与韧性、控制政府采购成本,构建基于柔性契约的应急物资政企联合储备定价博弈模型。以政府采购成本最小化、供应商利润最大化为目标,运用逆向归纳法依次求解供应商最优实物、原材料储备量决策和政府最优... 为提高突发事件应急物资保障能力与韧性、控制政府采购成本,构建基于柔性契约的应急物资政企联合储备定价博弈模型。以政府采购成本最小化、供应商利润最大化为目标,运用逆向归纳法依次求解供应商最优实物、原材料储备量决策和政府最优定价决策,并进行数值模拟仿真验证及变量敏感性分析。研究结果表明:与政府单独储备模式相比,该模型能够提升应急物资储备水平,提高政府应对突发事件的能力,同时降低政府采购成本并提高供应商收益,实现政企双方共赢。高灾害概率促使政府增加储备、企业调整生产,政府大规模的常规采购会给企业带来稳定收益,企业在现货市场供给率较大时会提高原材料储备量。灾害发生概率、现货市场采购价格、政府常规采购量、现货市场供给率等因素对政企双方决策及成本收益均有影响。研究结果可为政企双方应急物资储备量、采购价格以及激励双方合作储备提供决策参考。 展开更多
关键词 应急物资储备 STACKELBERG博弈 采购定价 数量柔性契约
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医患共同决策对老年慢性病共病患者家庭医生签约服务质量的影响
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作者 熊巨洋 朱璇 马赫 《中国卫生政策研究》 CSCD 北大核心 2024年第8期1-9,共9页
目的:深入剖析医患共同决策水平对老年慢性病共病患者家庭医生签约服务质量的作用路径,为推动慢性病健康管理、改善患者就医体验感和签约服务质量提供参考。方法:在武汉市和贵阳市采取多阶段随机抽样方法对599名老年慢性病共病患者及其... 目的:深入剖析医患共同决策水平对老年慢性病共病患者家庭医生签约服务质量的作用路径,为推动慢性病健康管理、改善患者就医体验感和签约服务质量提供参考。方法:在武汉市和贵阳市采取多阶段随机抽样方法对599名老年慢性病共病患者及其对应的63名签约医生开展问卷调查,借助分层回归模型分析医患共同决策水平对签约服务质量的作用路径。结果:我国中西部地区老年慢性病共病患者的医患共同决策得分为32.07±6.46,家庭医生签约服务质量得分为95.20±8.73,其中经济性和纵向连续性维度得分较低。分层回归模型分析结果显示医患共同决策水平对签约服务质量产生正向影响(β=0.369,P<0.05),家庭医生对签约患者的信任程度起到正向调节作用(β=0.548,P<0.05)。结论:我国中西部地区老年慢性病共病患者的医患共同决策水平和家庭医生签约服务质量均处于中等水平且有待提升,医患共同决策显著提升签约服务质量,对签约患者的信任程度强化共同决策对服务质量的正向效应。今后应加强医患共同决策、规范慢性病患者转诊服务、强化医患沟通信任,切实提升家庭医生签约服务质量。 展开更多
关键词 医患共同决策 慢性病共病 家庭医生 签约服务 服务质量
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健脾补肾活血汤辅助IVF-ET对不孕患者卵巢储备功能、胚胎质量及妊娠率的影响
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作者 董惠民 李宇燕 +1 位作者 周近宸 宋建玲 《四川中医》 2024年第5期148-151,共4页
目的:探讨健脾补肾活血汤辅助体外受精-胚胎移植(IVF-ET)对不孕患者卵巢储备功能、胚胎质量及妊娠率的影响。方法:选取医院2019年11月~2022年11月68例不孕症患者,随机数字表法分为两组,均34例。对照组采用IVF-ET治疗,观察组采用健脾补... 目的:探讨健脾补肾活血汤辅助体外受精-胚胎移植(IVF-ET)对不孕患者卵巢储备功能、胚胎质量及妊娠率的影响。方法:选取医院2019年11月~2022年11月68例不孕症患者,随机数字表法分为两组,均34例。对照组采用IVF-ET治疗,观察组采用健脾补肾活血汤辅助IVF-ET治疗。观察疗效,对比治疗前后中医证候积分、卵巢储备功能、胚胎质量及妊娠情况。结果:观察组较对照组总有效率升高(P<0.05);治疗后,观察组较对照组中医证候积分降低(P<0.05);治疗后,观察组较对照组卵泡最大直径、子宫内膜厚度均升高,卵巢体积降低(P<0.05);观察组较对照组可用胚胎数、优质胚胎数均升高(P<0.05);观察组较对照组生化妊娠率、临床妊娠率均升高(P<0.05)。结论:健脾补肾活血汤辅助IVF-ET治疗不孕症的疗效显著,能缓解患者症状,改善卵巢储备功能,提高胚胎质量及妊娠率。 展开更多
关键词 不孕症 健脾补肾活血汤 体外受精-胚胎移植 卵巢储备功能 胚胎质量 妊娠
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智能合约漏洞检测技术综述 被引量:1
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作者 董伟良 刘哲 +3 位作者 刘逵 黎立 葛春鹏 黄志球 《软件学报》 EI CSCD 北大核心 2024年第1期38-62,共25页
智能合约作为可信的去中心化应用,获得了广泛的关注,但其安全漏洞问题对其可靠性带来了巨大威胁.为此,研究者们利用各种前沿技术(如模糊测试、机器学习、形式化验证等)研究了多种漏洞检测技术,并取得了可观的效果.为了系统性地梳理与分... 智能合约作为可信的去中心化应用,获得了广泛的关注,但其安全漏洞问题对其可靠性带来了巨大威胁.为此,研究者们利用各种前沿技术(如模糊测试、机器学习、形式化验证等)研究了多种漏洞检测技术,并取得了可观的效果.为了系统性地梳理与分析现有智能合约漏洞检测技术,搜集截至2021年7月关于智能合约漏洞检测的84篇论文,根据它们的核心方法进行分类,从每种技术的实现方法、漏洞类型、实验数据等方面展开分析,同时对比国内外研究现状在这些方面的差异.最后,对现有的智能合约漏洞检测技术进行总结,探讨面临的挑战,并展望了未来的研究方向. 展开更多
关键词 智能合约 合约安全 合约可靠性 合约质量保障 漏洞检测 合约程序分析
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家庭医生签约服务质量评价指标体系的构建研究 被引量:1
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作者 许忠琴 龙江 +1 位作者 程春梅 许红 《卫生软科学》 2024年第4期71-73,92,共4页
参照服务质量(Service Quality,SERVQUAL)量表模型,应用文献分析法和专家咨询法,构建了家庭医生签约服务质量评价指标体系。该指标体系包含有形性、可靠性、响应性、保证性与移情性5个一级指标和24个二级指标,为科学评价家庭医生签约服... 参照服务质量(Service Quality,SERVQUAL)量表模型,应用文献分析法和专家咨询法,构建了家庭医生签约服务质量评价指标体系。该指标体系包含有形性、可靠性、响应性、保证性与移情性5个一级指标和24个二级指标,为科学评价家庭医生签约服务质量提供了有效的测评工具。 展开更多
关键词 家庭医生 签约服务 质量评价 指标体系
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化学新药研发企业对临床试验用药品委托制备的研发质量管理实践 被引量:2
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作者 陈辉 刘俊耀 夏广新 《上海医药》 2024年第1期65-68,79,共5页
临床试验用药品是化学新药研究与试验发展(以下简称研发)过程中里程碑式的产品,其制备的质量直接影响到临床受试者的用药安全性和临床试验结果的有效性。为确保临床试验用药品在委托制备过程中安全、有效且质量可控,本文阐明了化学新药... 临床试验用药品是化学新药研究与试验发展(以下简称研发)过程中里程碑式的产品,其制备的质量直接影响到临床受试者的用药安全性和临床试验结果的有效性。为确保临床试验用药品在委托制备过程中安全、有效且质量可控,本文阐明了化学新药药学研究在不同阶段下的研究重点,深入分析了工作中对临床试验用药品委托制备的质量管理所遇到的问题,探索出以“技术转出资料管理”“委托合同”“质量协议”三位一体,协同对临床试验用药品委托制备研发质量管理的模式,以期为新药研发企业的研发质量管理提供借鉴与思考。 展开更多
关键词 化学新药 临床试验用药品 委托合同 质量协议 技术转出资料管理
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基于遥感生态指数的广东石门台国家级自然保护区生态环境质量评价 被引量:1
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作者 黎毅 戴克元 +5 位作者 唐国平 杜建会 陈桃 江南 牛香豫 余扬波 《热带地理》 CSCD 北大核心 2024年第3期429-441,共13页
基于遥感生态指数(RSEI)定量评估了1997—2021年石门台自然保护区的生态环境质量变化,探究该自然保护区建立与管控级别提升前后的生态环境质量变化情况,并运用随机森林算法和相关性分析方法探讨演变的原因。结果表明:石门台自然保护区R... 基于遥感生态指数(RSEI)定量评估了1997—2021年石门台自然保护区的生态环境质量变化,探究该自然保护区建立与管控级别提升前后的生态环境质量变化情况,并运用随机森林算法和相关性分析方法探讨演变的原因。结果表明:石门台自然保护区RSEI值从1997年的0.637动态上升到2011年的0.714,随着自然保护区从省级升至国家级,生态环境质量稳步提高,2021年RSEI达到0.788;保护区生态环境质量变好的区域占比高达64.5%,其中,缓冲区改善较为明显,变差的区域主要集中在实验区人类活动频繁地区以及核心区高海拔山脊地带;RSEI对高程的响应最为明显,300~600 m生态环境质量最好,300 m以下和超过900 m生态环境质量相对较差;当土壤酸碱度为5.3、有机碳质量分数为4.1%、黏土质量分数为32%时,RSEI最高;居民活动从外向内(即实验区-缓冲区-核心区)对生态环境质量的影响程度逐渐降低且带来负面影响;时间上,RSEI与降水呈现正相关性,有23.6%的区域通过显著性检验(P<0.05),局部年份受降水的影响较大。总体上,石门台自然保护区生态环境质量变好趋势明显,今后应加强对高山顶部裸土区域以及低海拔人类活动频繁地区的保护和治理。 展开更多
关键词 生态环境质量 遥感生态指数 时空变化 随机森林 石门台自然保护区
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《合同编通则司法解释》对合同订立制度的发展 被引量:1
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作者 石宏 《上海政法学院学报(法治论丛)》 2024年第2期56-67,共12页
合同编是《中华人民共和国民法典》的重要组成部分,也是实践性和理论性最强、最易产生适用争议的部分。《最高人民法院关于适用〈中华人民共和国民法典〉合同编通则若干问题的解释》在尊重民法典立法原意的基础上,针对合同订立规则在司... 合同编是《中华人民共和国民法典》的重要组成部分,也是实践性和理论性最强、最易产生适用争议的部分。《最高人民法院关于适用〈中华人民共和国民法典〉合同编通则若干问题的解释》在尊重民法典立法原意的基础上,针对合同订立规则在司法适用中面临的难题和争议点,对合同成立的认定标准、合同订立中的第三人责任、预约合同的认定与违约救济、格式条款的认定和订入合同等重要内容作了细化和发展。这些亮点和发展对更好地贯彻实施民法典合同编,更好地规范和指导司法实践,统一法律适用标准将发挥重要的指导作用。 展开更多
关键词 《民法典》合同编 合同编解释 合同订立 预约合同 格式条款
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祁连山国家自然保护区生境质量时空特征及驱动因素分析 被引量:3
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作者 苏军德 赵晓冏 +1 位作者 李国霞 关海雯 《中国环境科学》 EI CAS CSCD 北大核心 2024年第5期2595-2605,共11页
借助InVEST模型分析了祁连山国家自然保护区生境质量和生境退化度的时空特征,同时利用空间关联的localMoran’sI方法和地理探测器,明确了其热点分布状况,深入探讨了生境质量时空分异的影响因素和驱动机制.结果表明:从东南到西北,生境质... 借助InVEST模型分析了祁连山国家自然保护区生境质量和生境退化度的时空特征,同时利用空间关联的localMoran’sI方法和地理探测器,明确了其热点分布状况,深入探讨了生境质量时空分异的影响因素和驱动机制.结果表明:从东南到西北,生境质量逐渐减低,2000~2020年,高生境质量区域逐年减少,低和较低生境质量区域明显增加,生境退化区域主要集中在威胁源(耕地、建设用地、未利用地、道路)附近的草地和林地;生境质量热点区域集中于研究区中部,且呈连片分布,东部和西部热点区域多被冷点分割,生境退化热点区域面积较少,占研究区总面积的6.72%~8.22%,但多在生态条件较好的区域;影响祁连山国家自然保护区生境质量时空分异的主要驱动因子是海拔、年均NDVI和人口数量,且各因子间呈非线性增强关系;生境质量与年均NDVI和降水呈显著正相关,与人口数量呈显著负相关,在不同海拔梯度上生境质量和生境退化程度具有明显差异,1751~2400m海拔梯度上生境质量和生境退化度均较低,海拔在2400~2950m区间内生境质量较高,但由于强烈的人类活动,其生境退化度也较大.在未来区域环境保护和土地资源利用中,更应防止低海拔区域(1751~2400m)生境质量的进一步恶化,在减少人类活动的同时,更应增强应对气候变化的保护措施,同时特别关注中海拔区域(2400~2950m)生境质量和生境退化度,从整体上提高区域生境质量,研究成果可为祁连山国家自然保护区精准制定环境保护策略和未来土地利用空间规划提供参考和借鉴. 展开更多
关键词 祁连山自然保护区 生境质量 驱动机制 生境退化度 地理探测 热点分析
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