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Tibet,the Himalaya,Asian monsoons and biodiversity-In what ways are they related？

Plant Diversity 2017年第5期39卷 233-244页

作者： robert A. Spicer Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Menglun Yunnan 666303 PR China School of Environment Earth and Ecosystem Sciences The Open University MK7 6AA UK

prevailing dogma asserts that the uplift of Tibet, the onset of the Asian monsoon system and high biodiversity in southern Asia are linked, and that all occurred after 23 million years ago in the ***, spanning the last 60 million years of Earth history, the geological, climatological and palaeontological evidence for this linkage is reviewed. The principal conclusions are that: 1) A proto-Tibetan highland existed well before the Neogene and that an Andean type topography with surface elevations of at least 4.5 km existed at the start of the Eocene, before final closure of the Tethys Ocean that separated India from Eurasia. 2) The Himalaya were formed not at the start of the India-Eurasia collision, but after much of Tibet had achieved its present elevation. The Himalaya built against a pre-existing proto-Tibetan highland and only projected above the average height of the plateau after approximately 15 Ma. 3)Monsoon climates have existed across southern Asia for the whole of the Cenozoic, and probably for a lot longer, but that they were of the kind generated by seasonal migrations of the Inter-tropical Convergence Zone. 4) The projection of the High Himalaya above the Tibetan Plateau at about 15 Ma coincides with the development of the modern South Asia Monsoon. 5) The East Asia monsoon became established in its present form about the same time as a consequence of topographic changes in northern Tibet and elsewhere in Asia, the loss of moisture sources in the Asian interior and the development of a strong winter Siberian high as global temperatures declined. 6) New radiometric dates of palaeontological finds point to southern Asia's high biodiversity originating in the Paleogene, not the Neogene.

关键词： Tibetan Plateau Himalaya Uplift history Monsoons Biodiversity Molecular phylogeny

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Energy consumption for creep fracture of metallic materials

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Acta Mechanica Sinica 2008年第4期24卷 469-472页

作者： robert A.Arutyunyan Universitetskii pr.28 Faculty of Mathematics and Mechanics Sankt-Petersburg State University Petrodvoretz Sankt-Petersburg 198504 Russia

The energy conservation law is applied to formulate the ductile and brittle creep fracture criterion for metallic materials. The criterion contains a summary of heat and latent energies. Assuming that the heat energy is given out so it has no effect on the fracture process, the ductile creep fracture criterion is simplified. To take into account the evaluation of the damage state of materials the compressibility condition is introduced and the brittle creep fracture law is formulated.

关键词： Ductile and brittle fracture criterion Energy conservation law Heat and latent energies

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A Study of Air/Space-borne Dual-Wavelength Radar for Estimation of Rain profiles

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Advances in Atmospheric Sciences 2005年第6期22卷 841-851页

作者： Liang LIAO robert MENEGHINI Goddard Earth Sciences ＆ Technology Center/Caelum Greenbelt MD 20771 Code 614.6 NASA/GSFC Greenbelt MD 20771

In this study, a framework is given by which air/space-borne dual-wavelength radar data can be used to estimate the characteristic parameters of hydrometeors. The focus of the study is on the Global precipitation Measurement （GPM） precipitation radar, a dual-wavelength radar that will operate in the Ku （13.6 GHz） and Ka （35 GHz） bands. A key aspect of the retrievals is the relationship between the differential frequency ratio （DFR） and the median volume diameter, Do, and its dependence on the phase state of the hydrometeors. It is shown that parametric plots of Do and particle concentration in the plane of the DFR and the radar reflectivity factor in the Ku band can be used to reduce the ambiguities in deriving Do from DFR. A self-consistent iterative algorithm, which does not require the use of an independent pathattenuation constraint, is examined by applying it to the apparent radar reflectivity profiles simulated from a drop size distribution （DSD） model. For light to moderate rain, the self-consistent rain profiling approach converges to the correct solution only if the same shape factor of the Gamma distributions is used both to generate and retrieve the rain profiles. On the other hand, if the shape factors differ, the iteration generally converges but not to the correct solution. To further examine the dual-wavelength techniques, the selfconsistent iterative algorithm, along with forward and backward rain profiling algorithms, are applied to measurements taken from the 2nd generation precipitation Radar （pr-2） built by the Jet propulsion Laboratory. Consistent with the model results, it is found that the estimated rain profiles are sensitive to the shape factor of the size distribution when the iterative, self-consistent approach is used but relatively insensitive to this parameter when the forward- and backward-constrained approaches are used.

关键词： rain rate dual-wavelength radar raindrop size distribution and GPM

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Hydroxychloroquine-azithromycin,doubase C,and QTc prolongation in congolese patients with COVID-19:Myth or reality?

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World Journal of Virology 2024年第2期13卷 107-114页

作者： Brady Madioko Makanzu Jean-robert Makulo Madone Ndona Mandina Dimosi Roger Wumba Murielle Mashi Longokolo Hippolyte Situakibanza Ossam Odio Donat Sonzi Mangala Constantin Mihigo Bashengezi Benjamin Kabwe Mwilambwe Gilbert Kabanda Kurhenga Benjamin Longo-Mbenza Roger Mwimba Mbungu Department of Cardiology Kinshasa University HospitalKinshasaDR CongoKinshasa University HospitalKinshasa 11Congo Nephrology Unit Kinshasa University HospitalKinshasaDemocratic Republic of the CongoKinshasa 11KinshasaCongo Department of Infectious Diseases Kinshasa University HospitalKinshasaDR CongoKinshasa 11Congo Department of Tropical Medicine University of KinshasaKinshasa 11Congo Department of Infectious Diseases University of Kinshasa HospitalKinshasa 11Congo Department of Tropical Medicine and Infectious Disease School of MedicineUniversity of KinshasaKinshasa 11Congo COVID-19 Treatment Center Kinshasa University HospitalKinshasaKinshasa 11Congo Centre de Recherche en Phytothérapie Pharmacopée Africaine et Technologie pharmaceutiqueKinshasa 11Congo Intensive Care Unit Kinshasa University HospitalKinshasa 11Congo Department of Gynecology and Obstetrics Kinshasa University HospitalKinshasa 11Congo

BACKGROUND QTc interval prolongation with an increased risk of torsade de pointes(Tsd)has been described in coronavirus disease 2019(COVID-19)patients treated with hydroxychloroquine(HCQ)and azithromycin(AZI)in Western *** the DR Congo,few studies have evaluated the safety of this association or proposed new *** To determine the incidence of QTc prolongation and Tsd in COVID-19 patients treated with HCQ-AZIs vs doubase C(new molecule).METHODS In present randomized clinical trial,we have included patients with mild or moderate COVID-19 treated with either HCQ-AZI or doubase ***(ECG)changes on day 14 of randomization were determined based on pretreatment *** QTc was defined as≥500 ms on day 14 or an increase of≥80 ms compared to pretreatment *** with cardiac disease,those undergoing other treatments likely to prolong QTc,and those with disturbed ECG tracings were excluded from the *** The study included 258 patients(mean age 41±15 years;52%men;3.4%diabetics,11.1%hypertensive).Mild and moderate COVID-19 were found in 93.5%and 6.5%of patients,*** baseline,all patients had normal sinus rhythm,a mean heart rate 78±13/min,mean pr space 170±28 ms,mean QRS 76±13 ms,and mean QTc 405±30 *** complaints suggesting cardiac involvement were reported during or after *** four patients(1.5%)experienced QTc interval prolongation beyond 500 ***,only five patients(1.9%)had an increase in the QTc interval of more than 80 *** prolongation was more significant in younger patients,those with high viral load at baseline,and those receiving HCQ-AZI(Pprolongation without Tsd was observed at a lower frequency in patients treated with HCQ-AZI vs doubase *** absence of comorbidities and concurrent use of other products that are likely to cause arrhythmia may explain our results.

关键词： QTc prolongation COVID-19 Doubase C HCQ-AZT Sub-Saharan Africa

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Modules and Structure presheaves for Arbitary Rings

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数学进展 1991年第1期 15-23页

作者： robert Wisbauer University of Dusseldorf West Germany

Basic techniques in the classical theory of commutative associative rings A with unity are:(i) The homological characterization of A in the category of A-modules. (ii) The rings of quotients of prime or semjprime rings A,(iii) The localization Ap at a prime ideal P and the structure sheaf on the prime spectrum of A. All these parts of structure theory are closely related to each other in this *** technique (i) was successfully applied to non-commutative rings, the parts (ii) and (iii) do not allow a satisfying extension to this more general situation. Moreover, in the special cases which admit corresponding constructions, the interplay between the different points usually gets *** the cateaory of left A-modules by a suitable subcategory σ[A] of bimodules over an arbitary (non-associative) ring A a natural extension of all three techniques under consideration which preserves relationships known from the classical situation is obtainedPart (i) and (ii) of the resulting theory can be fou

关键词： pr Modules and Structure presheaves for Arbitary Rings

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Landform type mediates compositional change in a hurricane-disturbed subtropical forest

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Ecological processes 2020年第1期9卷 292-304页

作者： robert L.Spicer Ariel ELugo Nathan Ruhl Department of Biological Science Rowan UniversityGlassboroNJ 08028USA International Institute of Tropical Forestry United States Department of Agriculture Forest ServiceJardín Botánico SurRío PiedrasPRUSA

Background:Categorization of topographical features into landform type is a long-standing method for understanding physiographic patterns in the *** in forest composition between landform types are driven primarily by concurrent differences in soil composition and moisture,but also disturbance *** studies have focused on the interaction between fire disturbance,succession,and landforms,but the effects of hurricane disturbance on compositional differences between landforms are poorly *** the study presented here,we assess compositional and structural differences between landform types in the tree community of a young sub-tropical forest that is frequently subjected to ***,we ask whether the tree community(1)changed structurally over the study period,(2)experienced compositional change over the study period,(3)is compositionally different between landform types,and(4)exhibits compositional change mediated by landform ***:The tree community experienced significant structural change over the course of our study,but compositional change was only significant for some ***:Despite large-scale,intense,and frequent hurricane disturbance to our study system,compositional change in the tree community was localized and only significant for some landform types.

关键词： Hurricane Forest Community Composition Change Succession Landform

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Nuclear DNA damages generated by reactive oxygen molecules (ROS) under oxidative stress and their relevance to human cancers, including ionizing radiation-induced neoplasia part I: Physical, chemical and molecular biology aspects

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Radiation Medicine and protection 2020年第4期1卷 140-152页

作者： robert Nilsson Ning-Ang Liu Vinca Institute of Nuclear Sciences Laboratory for Physical ChemistryUniversity of BelgradeSerbia State Key Laboratory of Radiation Medicine and protection School of Radiation Medicine and ProtectionCollaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou215123PR China

Oxidative stress(OS)occurs when the production of reactive oxygen species(ROS)overpowers the body’s natural defence,causing macromolecular *** role of OS in cancer initiation will depend on the likelihood of interaction between short lived ROS and nuclear *** this reason,a description of the physico-chemical properties of the various ROS that have been suggested to be involved is *** damages that are not repaired or mis-repaired during cell proliferation are necessary but not sufficient for cancer *** characteristics of DNA pro-mutagenic lesions and their potential role in cancer induction will be assessed,while stressing quantitative aspects as well as the importance of DNA repair.A low level of a specific DNA adduct can be compensated for by its persistence and high pro-mutagenic *** ionizing radiations generate some of the same oxidative ROS as those involved in OS,the cancer spectrum from whole body radiation exposure should be compared with that associated with OS.A causal link between electromagnetic radiations and human cancer lacks adequate scientific *** knowledge dictates that emphasis should be shifted from oxidative damages of low genotoxicity towards pro-mutagenic lesions induced by reaction products of nitrogen monoxide and complex highly reactive carbonyls,*** the peroxidation of lipids.A common shortcoming when assessing the role of OS in disease is the failure to distinguish between cause and *** the indicators of harmful OS be the result of the pathological condition in question,rather than its cause?Further,little attention has been paid to exposure in food to some of the same ROS(*** carbonyl compounds),as are generated endogenously by *** have the simultaneous presence of an ubiquitous high background of potent pro-carcinogenic DNA adducts which are not generated by ROS been taken into account.

关键词： Oxidative stress Cancer DNA adducts Ionizing radiation

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Investigating cooked rice textural properties by instrumental measurements

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Food Science and Human Wellness 2020年第2期9卷 130-135页

作者： Keyu Tao Wenwen Yu Sangeeta prakash robert G.Gilbert Joint International Research Laboratory of Agriculture and Agri-product Safety College of AgricultureYangzhou UniversityYangzhouJiangsu225009PR China The University of Queensland Centre for Nutrition and Food SciencesQueensland Alliance for Agriculture and Food InnovationBrisbaneQLD4072Australia Department of Food Science&Engineering Jinan UniversityHuangpu West Avenue 601Guangzhou CityGuangdong Province510632PR China The University of Queensland School of Agriculture and Food ScienceQLD4072Australia Jiangsu Key Laboratory of Crop Genetics and Physiology Key Laboratory of Plant Functional Genomics of the Ministry of EducationJiangsu Key Laboratory of Crop Genetics and PhysiologyCollege of AgricultureYangzhou UniversityYangzhou225009PR China

Foods wherein the starch is slowly digested contribute to good health by reducing the tendency to,and for the maintenance of,diabetes,obesity and colo-rectal *** foods with high amylose content have this desirable property,they usually do not have high sensory appeal and consumers are reluctant to eat *** sensory evaluation by trained human panelists is the best way to obtain consumer preferences,these tests are expensive,time-consuming and require considerable effort and *** measurements are easier,cheaper and invaluable for screening,but only useful if they correlate with human data for the type of food being ***,we test this using cooked rice with a wide range of amylose *** properties were correlated against quantitative descriptive panelist *** power and breakdown viscosity correlated with all panelist sensory attributes,but no other correlations with gelatinization properties were *** was a strong correlation between hardness and stickiness measured by texture profile analysis(TPA)and by panelists,suggesting that TPA can be used to measure hardness and stickiness of cooked *** also showed that breakdown viscosity is a reliable instrumental means to provide indicative measurements of hardness and rice preference,and swelling power is a predictor of rice stickiness.

关键词： Rice Texture Instrumental Viscosity Swellingpower

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Vegetation change detection using artificial neural networks with ancillary data in Xishuangbanna,Yunnan province,China

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Chinese Science Bulletin 2007年第A2期52卷 232-243页

作者： ZHANG ZhiMing Lieven VERBEKE Eva De CLERCQ OU XiaoKun robert De WULF Institute of Ecology and Geobotany Yunnan University Kunming 650091 China Laboratory of Forest Management and Spatial Information Ghent University Ghent 9000 Belgium

地球的及时、精确的变化察觉“ s 表面特征为更好计划，管理和环境研究提供基础。在这个学习 ANN 变化，察觉被用来执行植被变化察觉，并且与分类以后的方法相比。以前分类以后被执行 ANN 分类被用来产出多时间的植被地图。ANN 也被用来... 详细信息

地球的及时、精确的变化察觉“ s 表面特征为更好计划，管理和环境研究提供基础。在这个学习 ANN 变化，察觉被用来执行植被变化察觉，并且与分类以后的方法相比。以前分类以后被执行 ANN 分类被用来产出多时间的植被地图。ANN 也被用来在 2003 和 2004 为图象执行一个一个通行证分类。DEM 和斜坡被用作二条额外的隧道。在训练阶段期间，训练数据包括 36 个变化子类和 46 个没有变化子类被分开成 82 个子类。而且 NDVI differencing 方法被用来开发变化面具。当鉴别参考区域能为 ANN 那个生产更精确的变化察觉结果时，结果显示出那把 NDVI differencing 方法与视觉解释相结合通行证变化分类。而且，和 PCA 部件把举起和斜坡用作额外的隧道是有效的，在多山的学习区域执行基于 ANN 的变化察觉。把植被转变类分开成子类基于也是重要的光谱反应模式，特别为多山的地面。这个处理能减少地志的效果并且改进变化察觉精确性。

关键词：云南省西双版纳生态系统人工神经网络

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Soil resource availability and its effect on the ecophysiology and establishment of Stipa pulchra

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Journal of Plant Ecology 2019年第4期12卷 603-614页

作者： robert L.Fitch Erin J.Questad Edward G.Bobich Department of Biological Sciences California State Polytechnic UniversityPomona3801 West Temple Avenue PomonaCA 91768USA

Aims The objectives of this study were to(i)determine the importance of soil moisture and soil nitrogen availability as resource requirements for the establishment of Stipa pulchra,(ii)to examine how changes in slope within a local habitat can affect the accumulation of soil moisture and soil nitrogen and(iii)to measure the physiological re-sponses of *** among such slope *** The field experiment occurred in the San JoséHills of Southern California on the California State Polytechnic University,Pomona *** were established within three different slope loca-tions(shallow,moderate and steep)within four separate *** nitrogen treatments(ambient,addition and removal)were replicated within each slope location for all four canyons,and five *** plants were planted in each *** nitrogen accumula-tion and soil moisture,as well as other abiotic variables,were meas-ured across the varied slope locations and nitrogen *** measured the cover,stress,and reproduction of *** plants for 2 years and used a mesocosm experiment to determine how ***-chra responds to varying water and nitrogen *** Findings Stipa pulchra had a strong positive response to the wettest watering treatment and a weak response to nitrogen addition in the meso-cosm *** the field experiment,*** responded positively in moderate slope locations and did not respond to ni-trogen treatments,possibly due to *** patterns of soil moisture were driven by slope,soil compaction and solar *** nitrogen accumulation did not vary among slope *** restoration of ***,priority should be placed on managing soil moisture availability and determining suitable edaphic factors.

关键词： establishment ecophysiology slope soil moisture soil properties nitrogen deposition

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