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Influence of topographic aspect on floristic diversity, structure and treeline of afromontane cloud forests in the Bale Mountains,Ethiopia

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Journal of Forestry Research 2015年第4期26卷 919-931页

作者： Eshetu Yirdaw Mike Starr Mesele Negash Fantaw Yimer Department of Forest Sciences University of Helsinki Wondo Genet College of Forestry and natural resources Hawassa University

We studied the influence of east and west aspects on floristic composition, diversity, structure and treeline of afromontane cloud forests at Rira in the Bale Mountains, southeast Ethiopia. In addition, we studied how aspect relates to and/or interacts with other topographic and edaphic factors in influencing vegetation diversity. Strati- fied systematic plot sampling was used to survey the floristic composition, diversity and structure of forests on east- and west-facing slopes. The sample plot size was 20 x 20 m and a total of 36 plots were inventoried. A total of 72 composite soil samples were collected and analysed. Woody species richness of the forest on the east-facing slope was 1.7 times higher than on the west-facing slope. Shannon, Simpson and Log-series alpha diversity indices and evenness of forests on the east-facing slope were sig- nificantly higher than on the west-facing slope. NMDS ordination indicated that the east- and west-facing slopes formed two clusters of species and aspect explained 55.2 % and 10.4 % of the variation in species richness and abun- dance, respectively. There was no significant difference between aspects in stand structure except in dominantheight, which was higher on the east-facing slopes. There was significant interaction between aspect and elevation in influencing woody species diversity. The four plant com- munity groups, which were identified using cluster and indicator species analysis were represented differently on the east and west aspects. The treeline on the east-facing slope （3352 m） was located about 110 m higher than on the west-facing slope （3240 m）. Soil moisture deficiency was unlikely to be a limiting factor on either site. Near the equator, east-west aspect was shown to have considerable impact on floristic composition, diversity, structure, and treeline position of montane forests. Diurnal cloud move- ment patterns and its impact on microclimate of slope aspect should be taken into account in future studies

关键词： Afromontane Aspect Cloud forests Ethiopia Floristic diversity

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Disciplinary structure of geographic science in China

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Journal of Geographical Sciences 2022年第9期32卷 1637-1641页

作者： CHEN Fahu LI Xin WU Shaohong FAN Jie XIONG Juhua ZHANG Guoyou State Key Laboratory of Tibetan Plateau Earth System Resource and EnvironmentInstitute of Tibetan Plateau ResearchCASBeijing100101China Alpine Paleoecology and Human Adaptation Group(alpha) Institute of Tibetan Plateau ResearchCASBeijing100101China College of resources and Environment University of Chinese Academy of SciencesBeijing100049China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China Department of Earth Science National Natural Science Foundation of ChinaBeijing100085China The Geographical Society of China Beijing100101China

International and domestic circumstances have led to new opportunities and higher requirements for the development of geographic science in *** this paper,we propose a modified disciplinary structure for geographic science in China in the new *** science in China can be categorized into four secondary disciplines,i.e.,integrated geography,physical geography,human geography,and information geography,according to the current situation and expected *** tertiary disciplines under each secondary discipline are nearly fully developed,and a few quaternary disciplines under the tertiary disciplines are widely accepted and used in *** hope this new disciplinary structure can play a breakthrough role in improving the branches of geographic science,promoting the development of emerging disciplines under the framework of geographic science,and supporting national and international development strategies in the new era.

关键词： geographic science integrated geography physical geography human geography information geography disciplinary structure

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Biome reconstruction on the Tibetan Plateau since the Last Glacial Maximum using a machine learning method

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Science China Earth Sciences 2022年第3期65卷 518-535页

作者： Feng QIN Yan ZHAO Xianyong CAO Key Laboratory ofLand Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Alpine Paleoecology and Human Adaptation(alpha)Group State Key Laboratory of Tibetan Plateau Earth System Science(LATPES)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Historical biome changes on the Tibetan Plateau provide important information that improves our understanding of the alpine vegetation responses to climate ***,a comprehensively quantitative reconstruction of the historical Tibetan Plateau biomes is not possible due to the lack of quantitative methods that enable appropriate classification of alpine biomes based on proxy data such as fossil pollen *** this study,a pollen-based biome classification model was developed by applying a random forest algorithm(a supervised machine learning method)based on modern pollen assemblages on and around the Tibetan Plateau,and its robustness was assessed by comparing its results with the predictions of the biomisation *** results indicated that modern biome distributions reconstructed using the random forest model based on modern pollen data generally concurred with the observed zonal *** random forest model had a significantly higher accuracy than the biomisation method,indicating the former is a more suitable tool for reconstructing alpine biome changes on the Tibetan *** random forest model was then applied to reconstruct the Tibetan Plateau biome changes from 22 ka BP to the present based on 51 fossil pollen *** reconstructed biome distribution changes on the Tibetan Plateau generally corresponded to global climate changes and Asian monsoon *** the Last Glacial Maximum,the Tibetan Plateau was mainly desert with subtropical forests distributed in the *** the last deglaciation,the alpine steppe began expanding and gradually became zonal vegetation in the central and eastern *** meadow occupied the eastern and southeastern areas of the Tibetan Plateau since the early Holocene,and the forest-meadow-steppe-desert pattern running southeast to northwest on the Tibetan Plateau was established *** the mid-Holocene,subtropical forests extended north,which reflected the“optimum”***

关键词： Biome reconstruction Random forest algorithm Biomisation method Pollen data Last Glacial Maximum Tibetan Plateau

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Lactobacillus plantarum CCFM1180 attenuates obesity induced by estrogen deficiency by activating estrogen receptor alpha in abdominal adipose tissue and regulating gut microbiota-derived metabolites

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Food Science and Human Wellness 2024年第2期13卷 765-777页

作者： Qian Chen Chunxia Mei Min Guo Botao Wang Haiqin Chen Jianxin Zhao Gang Wang Wei Chen State Key Laboratory of Food Science and resources Jiangnan UniversityWuxi 214122China School of Food Science and Technology Jiangnan UniversityWuxi 214122China National Engineering Research Center for Functional Food Jiangnan UniversityWuxi 214122China (Yangzhou)Institute of Food Biotechnology Jiangnan UniversityYangzhou 225004China Bloomage Biotechnology Co. Ltd.Jinan 250000China

Lipid metabolism disorders commonly occur during *** deficiency has been shown to lead to excessive energy intake and abnormal lipid metabolism in ovariectomized rats,resulting in *** exhibit anti-obesity properties,and their underlying mechanism has been widely *** this study,we demonstrated the metabolic benefits of Lactobacillus plantarum CCFM1180 in suppressing appetite,controlling body weight,correcting obesity-induced abnormalities,enhancing liver lipid metabolism,and protecting liver function in estrogen-deficient *** mechanisms associated with the anti-obesity and anti-dyslipidemia effects of CCFM1180 on estrogen-deficient rats were *** results showed that CCFM1180 dramatically reduced food intake by activating the expression of estrogen receptor alpha(ERα)and increasing the level of leptin in abdominal adipose *** changes,combined with the increased butyrate concentration and recovered bile acid structure,helped enhance lipid ***,CCFM1180 treatment was found to be safer than exogenous estrogen ***,*** CCFM1180 could be considered a new therapeutic strategy for preventing and alleviating menopausal lipid abnormalities.

关键词： Bile acid Gut microbiota Menopause Ovariectomy Short chain fatty acid

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Relative abundance of American badger (Taxidea taxus) and red fox (Vulpes vulpes) in landscapes with high and low rodenticide poisoning levels

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Integrative Zoology 2012年第1期7卷 41-47页

作者： Gilbert PROULX Neil MacKENZIE alpha Wildlife Research&Management Sherwood ParkAlbertaCanada

Over the past decade,extensive poisoning campaigns have been conducted in southern Saskatchewan to control Richardson’s ground squirrel Spermophilus richardsonii(Sabine,1822)*** campaigns might impact on predator abundance by decreasing prey levels,and also through secondary *** spotlighting,we investigated the relative abundance of American badgers Taxidea taxus(Schreber,1777)and red fox Vulpes vulpes(Linnaeus,1758)in 2 study areas with road access and crops,but with different levels of *** the study area with relatively low poisoning(19.6%of the area traversed by roads),there were 2.2 times more American badgers per km of road and 6.4 times more red foxes per km than in the study area with high poisoning(89.7%of the area).It is recommended that an Integrated Pest Management program be developed to conserve natural predators across landscapes.

关键词： ground squirrels poisoning populations predators

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Disciplinary structure and development strategy of physical geography in China

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Journal of Geographical Sciences 2022年第9期32卷 1642-1653页

作者： CHEN Fahu WU Shaohong LIU Hongyan YANG Xiaoyan LIU Jianbao State Key Laboratory of Tibetan Plateau Earth System Resources and EnvironmentInstitute of Tibetan Plateau ResearchCASBeijing100101China Alpine Paleoecology and Human Adaptation Group(alpha) Institute of Tibetan Plateau ResearchCASBeijing100101China College of resources and Environment University of Chinese Academy of SciencesBeijing100049China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China College of Urban and Environmental Sciences Peking UniversityBeijing100871China College of Earth and Environmental Sciences Lanzhou UniversityLanzhou730000China

Physical geography,one of the branches of geography,is the basic discipline of geographic *** it is the scientific foundation of ecology,environmental science and other related *** geography focuses on spatial characteristics,evolution and regional differentiation of the earth’s *** the new period of rapid development of social economy,and science and technology,physical geography is more closely and widely connected with human geography and,information *** paper analyzed the forming process of the physical geography,expressed sub-discipline structure of integrated physical geography,sectoral physical geography,human living-environment geography,and proposed the development strategy of physical geography and its sub-branch disciplines,key priority of development goals and directions in China.

关键词： physical geography disciplinary structure development strategy

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Diffusion of helium in FCT zircon

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Science China Earth Sciences 2019年第4期62卷 719-732页

作者： Shun YU Wen CHEN Jingbo SUN Ze SHEN Laboratory of Isotope Thermochronology Institute of Geology Chinese Academy of Geological Sciences Key Laboratory of Deep-Earth Dynamics of Ministry of natural resources Institute of GeologyChinese Academy of Geological Sciences

To gain a better quantitative understanding of zircon(U-Th)/He ages and evaluate the applicability of zircon(U-Th)/He dating, the diffusion characteristics, He diffusion kinetics, helium partial retention zone(HePRZ), closure temperature, and(U-Th)/He ages were investigated using high-precision laboratory step heating experiments based on the thermally activated diffusion process. The ln(D/a^2) in Fish Canyon Tuff(FCT) zircons determined from laboratory step heating experiments was negatively correlated with reciprocal temperature, as expected for thermally activated volume diffusion. The zircon activation energies ranged from 144 to 184 kJ mol^(-1) with a mean of 169±12 kJ mol^(-1). The closure temperatures ranged from 144 to 216°C(a cooling rate of 10°C Ma^(-1) and an effective grain radius of 38–60 μm) with an average of 176±18°C. The calculated closure temperature increased with increasing cooling rate, yielding an average zircon He closure temperature of ～136°C at a slow cooling rate of 0.1°C Ma^(-1), whereas the closure value was ～199°C at a cooling rate of 100°C Ma^(-1). The closure temperature increased with the equivalent spherical radius assuming a constant cooling rate. The He ages from FCT zircons were negligibly affected by grain size because of the rapid cooling. He preserved in the zircon was sensitive to temperature and holding time, and the temperature range for zircon HePRZ gradually decreased with increasing holding time. The(U-Th)/He ages from 26 FCT zircons yielded an algorithmic mean of 28.3±0.3 Ma(S.E.) and a geometric mean of 28.4±0.3 Ma(S.E.), consistent with the ages of 28.4±1.9 Ma reported by other laboratories. The FCT zircons were characterized by rapid cooling, young(U-Th)/He ages with good reproducibility, and low alpha doses. Weak correlations between the He ages and effective uranium(eU) concentrations from the FCT zircons indicated radiation damage did not significantly affect He diffusivity.

关键词： Zircon Helium diffusion (U-Th)/He Closure temperature Thermochronometry

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Study of Scrape-Off-Layer Width in Ohmic and Lower Hybrid Wave Heated Double-Null Divertor Plasma in EAST

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Plasma Science and Technology 2011年第4期13卷 435-439页

作者：王亮徐国盛常加峰张炜颜宁丁斯晔刘少承明廷凤汪惠乾刘鹏蒋敏熊豪万宝年高翔郭后扬胡立群吴振伟朱思铮罗广南 Institute of Plasma Physics Chinese Academy of Sciences Tri alpha Energy Rancho Santa Margarita

Edge profiles in Ohmic and lower hybrid （LH） wave heated discharges in EAST are presented. A comparison of the measured profiles is made with those from the theoretical prediction for the scrape-off-layer （SOL） width. The edge plasma parameters are diagnosed by a triple probe divertor diagnostic system and fast reciprocating probes at the outer mid-plane. The experimental results show that the SOL width of double-null （DN） divertor plasmas in EAST appears to exhibit a negative dependence on the power crossing the separatrix, which is consistent with the collisional SOL scalings of JET and Alcator C-Mod. This will provide useful information for extrapolation to the ITER SOL width scaling for power deposition.

关键词： SOL width DN divertor plasma EAST tokamak

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Proteomics analysis of coronary atherosclerotic heart disease with different Traditional Chinese Medicine syndrome types before and after percutaneous coronary intervention

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Journal of Traditional Chinese Medicine 2024年第3期44卷 554-563页

作者： WANG Zhibo LI Ying WANG Daoping MA Bo MIAO Lan REN Junguo LIU Jinghua LIU Jianxun Beijing Key Laboratory of Pharmacology of Chinese Materia Region Institute of Basic Medical SciencesXiyuan HospitalChina Academy of Chinese Medical SciencesNational Clinical Research Center of Cardiovascular Disease of Traditional Chinese MedicineBeijing 100000China the National Key Facility for Crop Gene resources and Genetic Improvement Institute of Crop ScienceChinese Academy of Agricultural ScienceBeijing 100098China Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China

OBJECTIVE: To investigate the underlying protein molecular mechanisms of "Qi stagnation and blood stasis syndrome"(QS) and "Qi deficiency and blood stasis syndrome"(QD), as two subtypes of coronary artery disease(CAD) in Traditional Chinese Medicine(TCM),following percutaneous coronary intervention(PCI).METHODS: In this study, a total of 227 CAD patients with QS and 211 CAD patients with QD were enrolled;all participants underwent PCI. Label-free quantification proteomics were employed to analyze the changes in serum in two subtypes of CAD patients before and 6 months after PCI, aiming to elucidate the intervention mechanism of PCI in treating CAD characterized by two different TCM ***: Biochemical analysis revealed significant changes in tumor necrosis factor-α, high density lipoprotein cholesterol, blood stasis clinical symptoms observation, and Gensini levels in both patient groups post-PCI;Proteomic analysis identified 79 and 95 differentially expressed proteins in the QS and QD patient groups, respectively, compared to their control *** C8 alpha chain, complement factor H,apolipoprotein H, apolipoprotein B, plasminogen,carbonic anhydrase 2, and complement factor Ⅰ were altered in both comparison groups. Furthermore,enrichment analysis demonstrated that cell adhesion and connectivity-related processes underwent changes in QS patients post-PCI, whereas lipid metabolism-related pathways, including the peroxisome proliferator-activated receptor signaling pathway and extracellular matrix receptor interaction, underwent changes in the QD *** protein-protein interaction network analysis further enriched 52 node proteins, including apolipoprotein B,lipoprotein(a), complement C5, apolipoprotein A4,complement C8 alpha chain, complement C8 beta chain,complement C8 gamma chain, apolipoprotein H,apolipoprotein A-Ⅱ, albumin, complement C4-B,apolipoprotein C3, among others. The functional network of these proteins is posited to contribute to

关键词： percutaneous coronary intervention proteomics peptide mapping coronary atherosclerotic heart disease Traditional Chinese Medicine syndrome

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Effects of Topography and Land use on Woody Plant Species Composition and Beta Diversity in an Arid Trans-Himalayan Landscape, Nepal

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Journal of Mountain Science 2014年第5期11卷 1112-1122页

作者： Shishir PAUDEL Ole R VETAAS natural resources Ecology and Management Oklahoma State UniversityStillwater OK 74078 USA Department of Geography University of BergenPost Box 7800 N-5020 Bergen Norway

Distribution patterns of plant species are believed to be impacted by small-scale habitat heterogeneity. However, there have been few comparative studies examining how woody vegetation composition and diversity varies with aspects of different orientations in the Trans-Himalayan region at a local scale. Here, we examined the effects of incoming solar radiation on variation in woody species composition and compared the diversity between the northeast- and southwest-facing slopes in a Trans-Himalayan valley of Nepal. We also examined the implicit interactions between slope orientation and land use in determining the compositional variations between the slopes. We selected two pairs of northeast- and southwest-facing slopes where the first pair has a similar land use and differs in exposure only(Pisang site) while the other pair has clear differences in land use in addition to slope exposure(Braka site). In each site, we sampled 72 plots(36 on each slope) in which the presence and absence of woody species, environmental variables, and disturbance were recorded. Correspondence Analysis(CA) results suggested that the woody species composition significantly varied between northeast- and southwest-facing slopes at both sites, and was significantly correlated with measured environmental variables such as radiation index, altitude, and canopy openness. In the Braka site,mean alpha diversity was significantly higher on southwest-facing slopes. In contrast, beta diversity and gamma diversity were greater on northeast-facing slopes at both sites. Our results suggest that topographic variables(e.g., radiation index) affect species composition between the slopes, likely due to their influence on small scale abiotic environmental variables. However, the effects of land use, such as livestock browsing/grazing may interact with the effects of slope exposure, effectively reducing differences in species composition within slopes but enhancing the differences in beta diversity between

关键词： Correspondence analysis Diversity Environmental gradients Himalaya Land use Topographic aspect Woody vegetation

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