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Dynamic b_p in the L Band and Its Role in Improving the Accuracy of Soil Moisture Retrieval

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Chinese Geographical Science 2019年第2期29卷 283-292页

作者： JIANG Tao ZHAO Kai ZHENG Xingming CHEN Si WAN Xiangkun northeast institute of Geography and Agroecology Chinese Academy of Sciences University of Chinese Academy of Sciences Changchun Jingyuetan Remote Sensing Test Site Chinese Academy of Sciences

The parameter b_p in the tuo-omega(τ–ω)model is important for retrieving soil moisture data from passive microwave brightness ***,b_p depends on the observation mode(polarization,frequency,and incidence angle)and vegetation properties and varies with vegetation *** simplicity,previous studies have taken b_p to be a ***,to reduce the uncertainty of soil moisture retrieval further,the present study is of the dynamics of b_p based on the SMAPVEX12 experimental dataset by combining a genetic algorithm and the L-MEB microwave radiative transfer model of vegetated *** results show the ***,b_p decreases nonlinearly with vegetation water content(VWC),decreasing critically when VWC becomes less than 2 kg/m^***,there is a power law between b_p and VWC for both horizontal and vertical polarizations(R^2=0.919 and 0.872,respectively).Third,the effectiveness of this relationship is verified by comparing its soil-moisture inversion accuracy with the previous constant-b_p method based on the HiWATER *** so reveals that the dynamic b_p method reduces the root-mean-square error of the retrieved soil moisture by approximately 0.06 cm^3/cm^3,and similar improvement is obtained for the calibrated SMAPVEX12 *** results indicate that the dynamic b_p method is reasonable for different vegetation growth stages and could improve the accuracy of soil moisture retrieval.

关键词： soil vegetation microwave radiometry transmissivity

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CHAMPIONING GLOBALIZATION

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Beijing Review 2019年第28期62卷 16-17页

作者： Jiang Yuechun the institute of World Economics with the China institute of International studies

In the two decades of its existence, the Group of 20 (G20) has become a premier platform to come up with consensus for global economic governance. With the world today witnessing a growing backlash against globalization and surging populism and protectionism, global governance faces greater difficulties. The spreading unilateralism has increased downwa「d pressure on global economic growth, while trade protectionism is damaging the multilateral free trade system. With these developments, the G20 Summit in Osaka, Japan was an important gathering to provide a positive direction.

关键词： CHAMPIONING GLOBALIZATION existence two decades

Portal hypertension in patients with nonalcoholic fatty liver disease:Current knowledge and challenges

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World Journal of Gastroenterology 2024年第4期30卷 290-307页

作者： Anita Madir Ivica Grgurevic Emmanuel A Tsochatzis Massimo Pinzani Department of Gastroenterology Hepatology and Clinical NutritionUniversity Hospital DubravaZagreb 10000Croatia School of Medicine University of ZagrebZagreb 10000Croatia Faculty of Pharmacy and Biochemistry University of ZagrebZagreb 10000Croatia UCL institute for Liver and Digestive Health Royal Free Hospital and University College LondonLondon NW32PFUnited Kingdom

Portal hypertension(PH)has traditionally been observed as a consequence of significant fibrosis and cirrhosis in advanced non-alcoholic fatty liver disease(NAFLD).However,recent studies have provided evidence that PH may develop in earlier stages of NAFLD,suggesting that there are additional pathogenetic mechanisms at work in addition to liver *** early development of PH in NAFLD is associated with hepatocellular lipid accumulation and ballooning,leading to the compression of liver *** compression and intraluminal obstacles cause mechanical forces such as strain,shear stress and elevated hydrostatic pressure that in turn activate mechanotransduction pathways,resulting in endothelial dysfunction and the development of *** spatial distribution of histological and functional changes in the periportal and perisinusoidal areas of the liver lobule are considered responsible for the pre-sinusoidal component of PH in patients with ***,current diagnostic methods such as hepatic venous pressure gradient(HVPG)measurement tend to underestimate portal pressure(PP)in NAFLD patients,who might decompensate below the HVPG threshold of 10 mmHg,which is traditionally considered the most relevant indicator of clinically significant portal hypertension(CSPH).This creates further challenges in finding a reliable diagnostic method to stratify the prognostic risk in this population of *** theory,the measurement of the portal pressure gradient guided by endoscopic ultrasound might overcome the limitations of HVPG measurement by avoiding the influence of the pre-sinusoidal component,but more investigations are needed to test its clinical utility for this *** and spleen stiffness measurement in combination with platelet count is currently the best-validated non-invasive approach for diagnosing CSPH and varices needing *** change remains the cornerstone of the treatment of PH in NAFLD,together with correcting the comp

关键词： Non-alcoholic fatty liver disease Portal hypertension Mechanotransduction Endothelial dysfunction Hepatic venous pressure gradient

A case study of the role of climate, humans, and ecological setting in Holocene fire history of northwestern Europe

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Science China Earth Sciences 2015年第2期58卷 195-210页

作者： CUI QiaoYu Marie-José GAILLARD Fredrik OLSSON Annica GREISMAN Geoffrey LEMDAHL Ganna ZERNOVA Department of Biology and Environmental Science Linnaeus University Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of Sciences Department of Historical Philosophical and Religious Studies Ume University

We present the major results from studies of fire history over the last 11000 years(Holocene) in southern Sweden, on the basis of palaeoecological analyses of peat sequences from three small peat bogs. The main objective is to emphasize the value of multiple, continuous sedimentary records of macroscopic charcoal(macro-C) for the reconstruction of local to regional past changes in fire regimes, the importance of multi-proxy studies, and the advantage of model-based estimates of plant cover from pollen data to assess the role of tree composition and human impact in fire history. The chronologies at the three study sites are based on a large number of 14 C dates from terrestrial plant remains and age-depth models are achieved using Bayesian statistics. Fire history is inferred from continuous records of macro-C and microscopic charcoal counts on pollen slides. The Landscape Reconstruction Algorithm(LRA) for pollen-based quantitative reconstruction of local vegetation cover is applied on the three pollen records for plant cover reconstruction over the entire Holocene. The results are as follows:(1) the long-term trends in fire regimes are similar between sites, i.e., frequent fires during the early Holocene until ca. 9 ka BP, low fire frequency during the mid-Holocene, and higher fire frequency from ca. 2.5 ka BP;(2) this broad trend agrees with the overall fire history of northwestern and western Europe north of the Mediterranean area, and is due to climate forcing in the early and mid-Holocene, and to anthropogenic land-use in the late Holocene;(3) the LRA estimates of plant cover at the three sites demonstrate that the relative abundance of pine played a primordial role in the early and mid-Holocene fire history; and(4) the between-site differences in the charcoal records and inferred fire history are due to local factors(i.e., relative abundance of pine, geomorphological setting, and anthropogenic land-use) and taphonomy of charcoal deposition in the small peat bog

关键词： Holocene humans northwestern records pollen anthropogenic estimates vegetation proxy dates

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构建新型国际关系:超越历史赢得未来（英文）

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国际问题研究 2015年第2期 16-30,142页

作者：阮宗泽 China institute of International studies

The concept of new-type international relations is an enrichment and development of China's diplomatic theory, embodying China's vision of the evolution of the world order.

关键词：新型国际关系合作共赢中国特色大国外交世界秩序

Effectiveness and mechanisms of sodium-dependent glucose transporter 2 inhibitors in type 2 diabetes and heart failure patients

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World Journal of Cardiology 2024年第10期16卷 611-615页

作者： Yan-Xi Zhang Hai-Sheng Hu Bao-Qing Sun Department of Clinical Laboratory The First Affiliated Hospital of Guangzhou Medical UniversityState Key Laboratory of Respiratory DiseaseNational Center for Respiratory MedicineNational Clinical Research Center for Respiratory DiseaseGuangzhou Institute of Respiratory HealthGuangzhou 510120Guangdong ProvinceChina

We comment on an article by GrubićRotkvićet al published in the recent issue of the World Journal of *** specifically focused on possible factors affecting the therapeutic effectiveness of sodium-dependent glucose transporter inhibitors(SGLT2i)in patients with type 2 diabetes mellitus(T2DM)and their impact on ***2i inhibits SGLT2 in the proximal tubules of the kidneys,lowering blood glucose levels by inhibiting glucose reabsorption by the kidneys and causing excess glucose to be excreted in the *** studies have demonstrated a role of SGLT2i in cardiovascular function in patients with diabetes who take metformin but still have poor glycemic *** addition,SGLT2i has been shown to be effective in anti-apoptosis,weight loss,and cardiovascular ***,it is feasible to treat patients with T2DM with cardiovascular or renal diseases using SGLT2i.

关键词： Sodium-dependent glucose transporter inhibitors Type 2 diabetes mellitus Heart failure Treatment Cardiovascular disease

Effects of Row-Spacing on Canopy Structure and Yield in Different Plant Type Rice Cultivars

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Journal of northeast Agricultural University(English Edition) 2012年第4期19卷 11-19页

作者： Zhao Hai-xin Wang Xiao-xue Guo Zhen-hua Huang Xiao-qun Liu Hua-long Rice Research institute Shenyang Agricultural University Rice Research institute Heilongjiang Academy of Agricultural Sciences College of Agriculture Northeast Agricultural University

Two japonica rice varieties, Longjing 20 （more tillers and curved panicle type, MCP） and Longjing 21 （few tillers and half erect panicle type, FEP）, were used to study the effects of row-spacing on canopy structure, morphological characteristics and yield. The results showed that the percentage of productive tiller reduced first, and increased afterwards as row-spacing increasing. The relationship between row spacing and the percentage of productive tiller fitted a quadratic regression. The effects of row spacing on leaf area index （LAI） at later tillering stage and the highest stem number per square meter also followed a quadratic regression relationship with increasing first and then reducing. The effects of row-spacing on primary branch were larger than the secondary branch in Longjing 20. However, the trend in Longjing 21 was opposite. The relationship between row spacing and seed setting rate of the secondary branch or panicle was negatively correlated. An extreme significant negative correlation was obtained between seed setting rate of secondary branch in Longjing 20. There was no significant positive correlation between row-spacing and yield in Longjing 20 （R2=0.68）. However, the negative correlation between row-spacing and yield of Longjing 21 was extremely significant （R2=–0.96＊＊）. The canopy structure of MCP was more sensitive to row-spacing. The positive correlation between row spacing and the length of the flag leaf （R2=0.89＊＊）, the width of the flag leaf （R2=0.85＊）, the length of the last internode （R2=0.85＊）, the length of the last 2nd internode （R2=0.96＊＊） or the length of the panicle （R2=0.91＊＊） was significant or extremely significant in Longjing 20, but not in Longjing 21. The wider row-spacing promoted the accumulation of the dry matter of panicle, stem and leaf and the yield formation in MCP. The best row-spacing in Longjing 20 was 30 cm. For Longjing 21, the narrower row-spacing was better. The best row-spacing of it was 21 cm. These results su

关键词： row-spacing more tillers and curved panicle type (MCP) few tillers and half erect panicle type (FEP) canopy structure morphological characteristic yield

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美国经济新增长点及其影响（英文）

国际问题研究 2014年第4期 113-130,132页

作者：甄炳禧 China institute of International studies

The United States' economy is recovering from recession and is expected to be in high gear in the coming years, and the world economic power structure will also likely experience some new changes. All of these structure these developments can, to a large extent, be attributed to the United States' four new areas for economic growth. For China, the new growth areas for American economy have created both advantages and disadvantages, with opportunities generally outweighing challenges.

关键词：美国经济非常规能源先进制造业大数据

Dynamic quantum decoherence in Stern-Gerlach experiment

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Progress in Natural Science:Materials International 1999年第8期 3-5页

作者：孙昌璞战鹤 Beijing 100080 Changchun 130024 China China institute of Theoretical Physics Chinese Academy of Sciences institute of Theoretical Physica northeast Normal University

The Stern-Gerlach (SG) experiment is considered as a quantum measurement process measuring the spin states of particles from their spatial distribution. The wave packet collapse or quantum decoherence can be described as a dynamical evolution governed by the interaction between the space degrees of freedom and the spin degrees of freedom. The analytic solution of this exactly solvable model shows that the decaying process of coherence with time in the SG experiment obeys no longer the linear exponential law.

关键词： quantum decoherence wave packet collapse exponential law quartum irreversible process.