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An Integrated Approach to Crop Genetic Improvement

journal of Integrative Plant Biology 2012年第4期54卷 250-259页

作者： Martin A.j.Parry Malcolm j.Hawkesford Rothamsted Research Plant Science Department

The balance between the supply and demand of the major food crops is fragile, fueling concerns for long-term global food security. The rising population, increasing wealth and a proliferation of non- food uses （e.g. bioenergy） has led to growing demands on agricul- ture, while increased production is limited by greater urbanization, and the degradation of land. Furthermore, global climate change with increasing temperatures and lower, more erratic rainfall is projected to decrease agricultural yields. There is a predicted need to increase food production by at least 70% by 2050 and there- fore an urgent need to develop novel and integrated approaches, incorporating high-throughput phenotyping that will both increaseproduction per unit area and simultaneously improve the resource use efficiency of crops. Yield potential, yield stability, nutrient and water use are all complex multigenic traits and while there is genetic variability, their complexity makes such traits difficult to breed for directly. Nevertheless molecular plant breeding has the potential to deliver substantial improvements, once the component traits and the genes underlying these traits have been identified. In addition, interactions between the individual traits must also be taken into account, a demand that is difficult to fulfill with traditional screening approaches. Identified traits will be incorporated into new cultivars using conventional or biotechnological tools. In order to better understand the relationship between genotype, component traits, and environment over time, a multidisciplinary approach must be adopted to both understand the underlying processes and identify candidate genes, QTls and traits that can be used to develop improved crops.

关键词： Germpiasm variation nitrogen TIllING transformation trait water wheat yield.

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Fitting Full X-Ray Diffraction Patterns for Quantitative Analysis: A Method for Readily Quantifying Crystalline and Disordered Phases

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Advances in Materials Physics and Chemistry 2013年第1期3卷 47-53页

作者： Steve j. Chipera David l. Bish Chesapeake Energy Corporation Oklahoma City Oklahoma USA Indiana University Bloomington Indiana USA

Fitting of full X-ray diffraction patterns is an effective method for quantifying abundances during X-ray diffraction (XRD) analyses. The method is based on the principal that the observed diffraction pattern is the sum of the individual phases that compose the sample. By adding an internal standard (usually corundum) to both the observed patterns and to those for individual pure phases (standards), all patterns can all be normalized to an equivalent intensity based on the internal standard intensity. Using least-squares refinement, the individual phase proportions are varied until an optimal match is reached. As the fitting of full patterns uses the entire pattern, including background, disordered and amorphous phases are explicitly considered as individual phases, with their individual intensity profiles or “amorphous humps” included in the refinement. The method can be applied not only to samples that contain well-ordered materials, but it is particularly well suited for samples containing amorphous and/or disordered materials. In cases with extremely disordered materials where no crystal structure is available for Rietveld refinement or there is no unique intensity area that can be measured for a traditional RIR analysis, full-pattern fitting may be the best or only way to readily obtain quantitative results. This approach is also applicable in cases where there are several coexisting highly disordered phases. As all phases are considered as discrete individual components, abundances are not constrained to sum to 100%.

关键词： Full-Pattern Quantitative X-Ray Diffraction XRD

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基于APCS-MlR模型的西藏茶巴朗湿地表层沉积物重金属分布特征及来源解析

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冰川冻土 2024年第4期46卷 1356-1368页

作者：李伟杨博熊健谢鹏程张娜吕学斌西藏大学生态环境学院青藏高原生物多样性与生态环境保护教育部重点实验室西藏拉萨850000 天津大学环境科学与工程学院天津300350 甘肃省天水市生态环境局张家川分局甘肃张家川741500

湿地作为介于水体和陆地之间的第三生态系统,有着重要的生态功能。由于特殊的地理位置和自然环境条件,西藏地区形成了众多独具特色的天然高原湿地,在拉萨河流域湿地聚集现象尤为显著,茶巴朗湿地就是该流域的重要成员之一。近年来,随着... 详细信息

湿地作为介于水体和陆地之间的第三生态系统,有着重要的生态功能。由于特殊的地理位置和自然环境条件,西藏地区形成了众多独具特色的天然高原湿地,在拉萨河流域湿地聚集现象尤为显著,茶巴朗湿地就是该流域的重要成员之一。近年来,随着城市旅游业、农牧业大力发展,湿地面积、动植物资源丰富度和湿地功能等方面出现了不同程度的退化。为了解西藏茶巴朗湿地表层沉积物的重金属分布特征与污染状况,于2021年8月共采集湿地表层沉积物样品19个,分别测定了沉积物样品中重金属含量,同时利用内梅罗污染指数和潜在生态风险指数对研究区重金属污染现状进行评价,并通过绝对主成分得分-多元线性回归模型(APCS-MlR)进行重金属来源解析。结果发现,茶巴朗湿地表层沉积物中Cu、Cr、Ni、Zn、Pb、Cd、As和Hg元素含量分别是西藏背景值的1.71、0.56、0.65、1.02、1.31、1.52、0.92、1.48倍,但远低于《土壤环境质量农用地土壤污染风险管控标准(试行)》(GB 15618—2018)中筛选值,与西藏其他高原湿地相比,沉积物重金属富集水平较低;研究区内梅罗污染指数均值为1.68,属轻度污染水平;潜在生态风险指数RI均值为134.45,属于轻微生态风险。绝对主成分得分-多元线性回归模型结果表明,茶巴朗湿地沉积物中Cu、Zn、Pb、Hg来源于交通运输和农业活动混合源,Cr、Ni来源于土壤母质源,As来源于地热源,Cd来源于地热源、交通运输和农业活动混合源,研究区湿地的沉积物重金属主要影响途径为交通运输和农业活动混合输入。本研究揭示了茶巴朗湿地沉积物中重金属元素的赋存现状、空间分布特征和生态风险等级,以及重金属的可能来源,客观了解湿地环境质量现状,为茶巴朗湿地和其他区域高原湿地后续的污染防治工作和可持续发展提供科学依据和理论支撑。

关键词：茶巴朗湿地沉积物重金属分布特征风险评价 APCS-MlR

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“暴风雪”出没注意! 俄罗斯与核武器下

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海陆空天惯性世界 2024年第3期 2-17页

作者：斯蒂芬·布兰克长弓(编译) 不详

译自美国陆军作战学院《俄罗斯核武器:过去、现在和未来》系列研究报告(斯蒂芬·布兰克/Stephen ***主编)第七章。

关键词：布兰克核武器俄罗斯暴风雪

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肾炎康复片联合恩格列净治疗糖尿病肾病的临床研究

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现代药物与临床 2024年第8期39卷 2072-2076页

作者：王瑶吕元军凌龙吴玉程姗姗赵欣桐天津市天津医院内分泌科天津300211 天津市天津医院检验科天津300211

目的探讨肾炎康复片联合恩格列净片治疗糖尿病肾病的临床效果。方法选取2022年7月—2023年11月天津市天津医院门诊收治的70例糖尿病肾病患者,用随机表法将患者分为对照组和治疗组,各35例。对照组空腹口服恩格列净片,10 mg/次,1次/d。治... 详细信息

目的探讨肾炎康复片联合恩格列净片治疗糖尿病肾病的临床效果。方法选取2022年7月—2023年11月天津市天津医院门诊收治的70例糖尿病肾病患者,用随机表法将患者分为对照组和治疗组,各35例。对照组空腹口服恩格列净片,10 mg/次,1次/d。治疗组在对照组的基础上口服肾炎康复片,5片/次,3次/d。两组连续治疗12周。比较两组的临床疗效、糖代谢指标、肾功能指标和血清炎症指标。结果治疗后,对照组总有效率为71.42%,治疗组的总有效率为88.57%,组间比较差异有统计学意义(P<0.05)。治疗后,两组的空腹血糖(FPG)、糖化血红蛋白(HbA1c)均显著降低(P<0.05),治疗后,两组FPG、HbA1c组间比较差异无统计学意义。治疗后,两组尿素氮(BUN)、血肌酐(Scr)、尿微量白蛋白/肌酐比值(UACR)均较前下降(P<0.05),治疗组BUN、Scr、UACR比对照组更低(P<0.05)。治疗后,两组血清转化生长因子(TGF)-β1、肿瘤坏死因子(TNF)-α水平均较前下降(P<0.05),治疗组患者血清TGF-β1、TNF-α水平比对照组更低(P<0.05)。结论肾炎康复片联合恩格列净片治疗糖尿病肾病提高了临床疗效,可改善其血糖水平,发挥肾脏保护作用,减轻患者的炎症反应。

关键词：肾炎康复片恩格列净片糖尿病肾病空腹血糖糖化血红蛋白尿素氮血肌酐尿微量白蛋白/肌酐比值血清转化生长因子-β1 肿瘤坏死因子-α

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Simulation of rainfall-runoff and watershed convergence process in the upper reaches of Heihe River Basin,july 2002

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Science China Earth Sciences 2004年第Z1期47卷 1-8页

作者： GAO Yanhong l(U) Shihua CHENG Guodong Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The watershed flow concentration scheme in the distributed hydrology-soil- vegetation model (DHSVM) is coupled with the mesoscale atmospheric model MM5 version 3.5, in which the Oregen States University land surface model (OSUlSM) was involved. The flood event which happened in july 2002 in the upper reaches of Heihe river basin is simulated and the surface flow convergence process is shown with this coupled model. It has been concluded that times water head reaches each place of the basin are different. Water amount at each point is split-flow proportionally as the drops in elevation between it and neighbor points. large part of the water amount pass away in greater slope direction and small part pass away in smaller slope *** of the slope convergence makes the atmospheric model redistributes the surface water laterally.

关键词： distributed hydrology-soil-vegetation model, mesoscale atmospheric model, watershed flow concentration process.

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Reduced striatal volumes in Parkinson’s disease:a magnetic resonance imaging study

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Translational Neurodegeneration 2012年第1期1卷 132-139页

作者： Toni l Pitcher Tracy R Melzer Michael R MacAskill Charlotte F Graham leslie livingston Ross j Keenan Richard Watts john C Dalrymple-Alford Tim j Anderson Department of Medicine University of OtagoChristchurchNew Zealand New Zealand Brain Research Institute 66 Stewart StChristchurch 8011New Zealand Department of Psychology University of CanterburyChristchurchNew Zealand College of Medicine University of VermontBurlingtonVTUSA Christchurch Radiology Group ChristchurchNew Zealand Department of Neurology Canterbury District Health BoardChristchurchNew Zealand

Background:The presence and extent of structural changes in the brain as a consequence of Parkinson’s disease(PD)is still poorly ***:High-resolution 3-tesla T1-weighted structural magnetic resonance images in sixty-five PD and 27 age-matched healthy control participants were ***,caudate,and intracranial volumes were manually traced in the axial plane of 3D reconstructed *** nuclei volumes were normalized to intracranial volume for statistical *** status was assessed using the Unified Parkinson’s Disease Rating Scale and Hoehn and Yahr *** status was assessed using global status tests and detailed neuropsychological ***:Both caudate and putamen volumes were smaller in PD brains compared to controls after adjusting for age and *** volumes were reduced by 11%(p=0.001)and putamen volumes by 8.1%(p=0.025).PD striatal volumes were not found to be significantly correlated with cognitive or motor ***:Small,but significant reductions in the volume of both the caudate and putamen occur in PD *** reductions are independent of the effects of age and gender,however the relation of these reductions to the functional loss of dopamine,which is characteristic of PD,remains unclear.

关键词： Magnetic resonance imaging Volumetry Caudate Putamen Parkinson’s disease

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The Influence of Systematic Errors on the Asian Summer Monsoon Circulation

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Advances in Atmospheric Sciences 2000年第4期17卷 576-586页

作者： P. l. S. Rao IBM India Research laboratory Indian Institute of Technology

The systematic errors of wind field associated with the prediction of Asian summer monsoon and their impact on the monsoon circulation have been studied in this paper. The daily operational analyses and fore-casts (up to day-5) of the National Centre for Medium Range Weather Forecasting (NCMRWF), India, over the Asian summer monsoon domain for the period june, july and August of 1995 are made use for the purpose. The systematic errors associated with the low level flow delineate, reduction in the strength of trade winds leading to weakening of cross equatorial flow as well as westerly flow over Indian Ocean. The upper level errors connote weakening of Tibetan anticyclone and reduction in the strength of return flow into the Southern Hemisphere. Further, these errors evince growing tendency with increase in the forecast period. Apart from the general underestimation of kinetic energy budget terms, the model forecasts fail to represent the transient eddies. The forecasts show increasing trend in the conversion of eddy to mean kinetic energy. These errors enfeeble Asian summer monsoon circulation with increase in the forecast period. Key words Monsoon - Systematic errors - Kinetic energy budget The author is grateful to the NCMRWF for providing data and computing facilities to carry out the present study.

关键词： Monsoon Systematic errors Kinetic energy budget

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UNRAVElING ECOTOURISM PRACTICE:PROBlEM ANAlYSIS BASED ON STAKEHOlDERS

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Chinese Geographical Science 2004年第1期14卷 82-89页

作者： l1UXue-mei BAOji-gang CenterforTourismPlanningandResearch ZhongshanUniversityGuangzhou510275P.R.China

Despite the considerable literatures defined what Ecotourism is or should be, it is experiencing vario- us practices with different features. Now the term "Ecotourism" is almost applied to all tourism activities which are based on nature. Faced to the flooding of those unqualified Ecotourism, it is of great necessity to put forward professional claim. The present writer holds that the key to the realization of rigorous Ecotourism chiefly lies in the relationships among the different interest groups involved in it. So the focus of this paper is just on giving a special analysis to the interest relations between those stakeholders which include local government, tour-operators, local residents and eco-tourists, and thus helping to find out what wrong is in those unqualified Ecotourism and the roots of those problems.

关键词： Ecotourism stakeholder interest relations

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NUMERICAl SIMUlATION OF CEllUlAR/DENDRITIC PRIMARY SPACING

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Acta Metallurgica Sinica(English letters) 2004年第5期17卷 761-766页

作者： W.Q,Zhang l.Xiao DepartmentofMaterialsScienceandEngineering LiaoningTechnicalUniversityFuxin123000China

A numerical model has been established to calculate the primary spacing of cellular or dendritic structure with fluid flow considered. The computing results show that the primary spacing depends on the growing velocity, the temperature gradient on the interface and fluid flow. There is a critical growing velocity for the cell-dendrite transition, which has a relationship with the temperature gradient: Rcr = (3-4)×10-9GT. Fluid flow leads to an increase of the primary spacing for dendritic growth but a decrease for cellular growth, resulting in an instability on the interface.

关键词： primary spacing model fluid flow l/S interface

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