Subjects: Geosciences >> Hydrology submitted time 2018-10-23 Cooperative journals: 《干旱区地理》
Abstract： 祁连山自然保护区是河西地区重要的水源涵养区，而灌丛作为祁连山主要植被类型之一，对该区水源涵养功能具有举足轻重的作用。本文以黑河上游天涝池流域两种典型亚高山灌木为研究对象，基于2014 、2015 年野外观测和ArcGIS10.1分析功能，获得灌木生长季期间生态参数(叶面积、叶面积指数和比叶面积)的变化；同时，结合分辨率为0.5m×0.5m的LiDAR数据和Geoeye-1影像数据，估算研究区灌木叶面积指数的空间分布。研究结果表明：灌木在生长季期间比叶面积值在一定范围内波动；叶面积、叶面积指数变化较大。其中，在6月、7月份增加最明显，8月份趋于稳定，9月份叶片开始凋落。其次，随海拔梯度水热条件的不同，流域灌木叶面积指数空间异质性较大，以海拔3 400m为节点，在3 200~3 400 m 海拔带叶面积指数呈递增趋势，在3 400~3 750 叶面积指数呈递减趋势。
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2022-12-20 Cooperative journals: 《中国全科医学》
Abstract：
Background Coronary heart disease belongs to the category of "chest numbness and heartache" in traditional Chinese medicine. Blood stasis syndrome is the most common syndrome distribution. Expand on basis of this study in the early stage of the team, for the first use of arterial elasticity and the vascular endothelial function testing combined apolipoprotein ratios combined diagnosis of young and middle-aged CHD, blood stasis, early detection of young and middle-aged coronary heart disease, blood stasis is dedicated to providing you with new ideas, also can be used to supplement optimization the diagnostic criteria of CHD with blood stasis syndrome. Objective To investigate the correlation between ABI, baPWV, FMD, apoB/apoA-1 and blood stasis syndrome in young and middle-aged patients with CHD, and its diagnostic and predictive value. Method A comprehensive search for eligible cases was conducted from December 1, 2016 to December 1, 2021 in China-Japan Friendship Hospital. Totally 127 young and middle-age CHD patients with blood stasis syndrome and 79 cases without blood stasis syndrome were included. Data of ABI, baPWV, FMD and apoB/apoA-1 ratio before PCI was extracted and compared in multivariate logistic regression analysis. The accuracy of our prediction model was evaluated by ROC curve. Results Multivariate Logistic regression analysis showed that ABI, baPWV, FMD, apoB/apoA-1 radio were independently correlated with young and middle-age CHD patients with blood stasis syndrome and the differences were statistically significant (P=0.001, P<0.001, P<0.001, P=0.035, respectively). The regression equation for predicting probability P was P=1/[1+e-(5.519-0.599×ABI+0.297×BAPWV-0.515×FMD+0.172×apoB/apoA-1)]. ROC curve analysis showed that the diagnosis of young and middle-age CHD patients with blood stasis syndrome was significant if ABI≤1.19 (1/ABI=0.84), baPWV≥14.93m·s-1, FMD≤8.33% (1/FMD=0.12) or apoB/ APOA-1 radio ≥0.72. The AUC of ABI, baPWV, FMD, apoB/APOA-1 radio and P value were 0.647, 0.680, 0.676, 0.606 and 0.807, respectively. The AUC of prediction probability P was higher than that of each index alone (P<0.001) , whose sensitivity and specificity were 0.740 and 0.734 respectively. Conclusion ABI, baPWV, FMD and apoB/APOA-1 were independently correlated with young and middle-age CHD patients with blood stasis syndrome and combined evaluation of them possesses the best diagnostic predictive efficiency for early identification and intervention.
Subjects: Biology >> Botany >> Applied botany submitted time 2021-07-20 Cooperative journals: 《广西植物》
Abstract： To explore the impact of Chimonobambusa utilis management on species diversity and dominant populations structure of Castanopsis platyacantha community in Jinfo Mountain, the natural and the managed community of Castanopsis platyacantha in Jinfo Mountain were used as the research object to analyze species composition characteristics, species diversity and dominant populations structure in two communities. The results were as follows: (1) A total of 84 vascular plants in the plots were found, belonging to 40 families and 63 genera, dominated by Lauraceae, Rosaceae, Fagaceae and Theaceae; Castanopsis platyacantha was the dominant species in the community, Schima sinensis and Lithocarpus henryi were the subordinates and Chimonobambusa utilis was the dominant species in the shrub layer, which the species composition of Castanopsis platyacantha community in Jinfo Mountain was similar to other subtropical regions. (2) The species richness of the shrub layer of the managed community was significantly lower than that of the natural community, the Shannon-wiener index and Pielou index of the herb layer was significantly lower than that of the natural community. (3) Dominant tree species Castanopsis platyacantha and Lithocarpus henryi in the natural community were of stable populations, but those were of declining populations in the managed community, and Schima sinensis in two communities appeared to be in decline. (4) The ratio of total sprouts to total individuals, number of multi-stemmed individuals/number of all individuals and seedling relative dominance value of Castanopsis platyacantha, Schima sinensis and Lithocarpus henryi in the natural community were higher than in the management community. In conclusion, the Chimonobambusa utilis management have a negative impact on the species diversity with the strongest on the shrub and herb layers of Castanopsis platyacantha community in Jinfo Mountain, indicating managed activities significantly affect the renewal and maintenance of the dominant species in Castanopsis platyacantha community.
Subjects: Geosciences >> Marine Sciences submitted time 2017-03-22 Cooperative journals: 《中国科学院院刊》
Abstract：水圈包括海洋、湖沼、河流、冰川、地下水等，水圈中居住着地球上一半以上的微生物，包括细菌、古菌、真菌、藻类、病毒等，蕴含着地球上最大的微生物组。已有的研究表明，水圈微生物在重要元素生物地球化学循环中发挥关键驱动作用。但是，人们对水圈微生物组的核心科学问题，即微生物如何发挥驱动作用至今了解不多。最近，国家自然科学基金委员会“水圈微生物驱动地球元素循环的机制”重大研究计划（简称“水圈微生物计划”）正式立项。该计划拟选择典型水圈环境，解析微生物群落构建及与环境之间的相互作用、微生物物质与能量代谢机制以及微生物代谢活动的生态学意义与贡献，从而揭示水圈微生物驱动碳、氮、硫等元素生物地球化学循环的机制。文章简述了该计划提出的背景与依据，以及涉及的主要科学问题和研究设想。
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