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Oxygation Enhances Growth,Gas Exchange and Salt Tolerance of Vegetable Soybean and Cotton in a Saline Vertisol

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journal of Integrative Plant Biology 2009年第7期51卷 675-688页

作者： Surya P. Bhattarai David j. midmore Centre for Plant and Water Science Department of Molecular and Life SciencesCentral Queensland University

Impacts of salinity become severe when the soil is deficient in oxygen. OxygaUon （using aerated water for subsurface drip irrigation of crop） could minimize the impact of salinity on plants under oxygen-limiting soil environments. Pot experiments were conducted to evaluate the effects of oxygation （12% air volume/volume of water） on vegetable soybean （moderately salt tolerant） and cotton （salt tolerant） in a salinized vertisol at 2, 8, 14, 20 dS/m ECe. In vegetable soybean, oxygation increased above ground biomass yield and water use efficiency （WUE） by 13% and 22%, respectively, compared with the control. Higher yield with oxygation was accompanied by greater plant height and stem diameter and reduced specific leaf area and leaf Na^＋ and CI^- concentrations. In cotton, oxygation increased lint yield and WUE by 18% and 16%, respectively, compared with the control, and was accompanied by greater canopy light interception, plant height and stem diameter. Oxygation also led to a greater rate of photosynthesis, higher relative water content in the leaf, reduced crop water stress index and lower leaf water potential. It did not, however, affect leaf Na^＋ or CI^- concentration. Oxygation invariably increased, whereas salinity reduced the K^＋： Na^＋ ratio in the leaves of both species. Oxygation improved yield and WUE performance of salt tolerant and moderately tolerant crops under saline soil environments, and this may have a significant impact for irrigated agriculture where saline soils pose constraints to crop production.

关键词： cotton irrigation light interception oxygation saline soil salt exclusion stem diameter vegetable soybean

SEmI-SOLID mICROSTRUCTURE AND ITS EVOLUTION OF WROUGHT ALUmINUm ALLOY BY DIRECTLYHEATING-ISOTHERmAL TREATmENT

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Acta metallurgica Sinica(English Letters) 2004年第6期17卷 856-861页

作者： X.T.Liu j.Z.Cui TheKeyLaboratoryofElectromagneticProcessingofmaterials MinistryofEducationNortheasternUniversityShenyang110004China

microstructure evolution of wrought aluminum alloy extruded rods and the mechanism of liquid phase formation during reheating were investigated. And the relation between the volume fraction of liquid phase and the recrystallization microstructure was proposed. The results show that increase in reheating temperature and time can augment the volume fraction of liquid phase and accelerate the grain spheroidization, as a result of which the requirement of semi-solid forming can be satisfied. Due to the higher aberration energy of grain boundary, the melting point is lowered as a result of the easy diffusion of atoms. At higher reheating temperature the grain boundary melts, the growth of the recrystallized grain is inhibited and the grain is refined. The composition of the low melt-point phase along the recrystallized grains was determined using EDS. It can be seen from the experimental results that when the extrusion rod of the wrought aluminum alloy is reheated at 610℃ for 20min, perfect fine equiaxial grains can be obtained, the average grain size is about 66.34μm and the volume fraction of solid phase is about 68%.

关键词： wrought aluminum alloy hot extrusion reheating mechanism of micro- structual evolution spheroidization volume fraction of solid phase

metabolic reprogramming in tumors:Contributions of the tumor microenvironment

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Genes & Diseases 2020年第2期7卷 185-198页

作者： Andrew N.Lane Richard m.Higashi Teresa W-m.Fan Center for Environmental and Systems Biochemistry Markey Cancer CenterDepartment of Toxicology and Cancer BiologyUniversity of KentuckyUSA

The genetic alterations associated with cell transformation are in large measure expressed in the metabolic phenotype as cancer cells proliferate and change their local environment,and prepare for ***,the fundamental biochemistry of cancer cells is generally the same as in the untransformed cells,but the cancer cells produce a local environment,the TmE,that is hostile to the stromal cells,and compete for *** order to proliferate,cells need sufficient nutrients,either those that cannot be made by the cells themselves,or must be made from simpler ***,in solid tumors,the nutrient supply is often limiting given the potential for rapid proliferation,and the poor quality of the ***,cancer cells may employ a variety of strategies to obtain nutrients for survival,growth and *** much has been learned using established cell lines in standard culture conditions,it is becoming clear from in vivo metabolic studies that this can also be misleading,and which nutrients are used for energy production versus building blocks for synthesis of macromolecules can vary greatly from tumor to tumor,and even within the same *** we review the operation of metabolic networks,and how recent understanding of nutrient supply in the TmE and utilization are being revealed using stable isotope tracers in vivo as well as in vitro.

关键词： Cancer metabolism Nutrient supply Stable isotope resolved metabolomics Tumor microenvironment metabolic flux

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糖耐量受损:心血管疾病的重要危险因子

中国组织工程研究与临床康复 2007年第51期11卷 10344-10348页

作者：夏娟喻明上海交通大学附属第六人民医院内分泌科上海市200233

学术背景:糖耐量受损阶段的异常血糖水平已导致机体组织器官损害,尤其是心血管病变。此阶段心血管疾病的患病率和死亡率均显著高于正常糖代谢人群,其心血管病变的危险性已接近糖尿病。目的:探讨糖耐量受损发生心血管疾病的危险性及其伴... 详细信息

学术背景:糖耐量受损阶段的异常血糖水平已导致机体组织器官损害,尤其是心血管病变。此阶段心血管疾病的患病率和死亡率均显著高于正常糖代谢人群,其心血管病变的危险性已接近糖尿病。目的:探讨糖耐量受损发生心血管疾病的危险性及其伴随的相关危险因素。检索策略:由该论文的研究人员应用计算机检索Pubmed、Blackwell Synergy数据库1997-01/2007-06的相关文献,检索词"impaired glucose tolerance,diabetes mellitus,cardiovascular disease",并限定文章语言种类为English。同时计算机检索中国期刊全文数据库1998-01/2007-06的相关文献,检索词为"糖耐量受损,糖尿病,心血管疾病,血糖漂移",并限定语种为中文。共检索到109篇文献,对资料进行初审,纳入标准:评估糖代谢状况的检测方法,糖耐量受损与2型糖尿病,糖耐量受损与心血管疾病。排除标准:重复性研究。文献评价:文献的来源主要是通过对糖耐量受损的定义、流行病学特点、评估方式及其危害性进行汇总分析。所选用的36篇文献中,6篇为综述,其余为临床或基础实验研究。资料综合:糖耐量受损与正常血糖者相比,已呈现明显的糖代谢紊乱。糖耐量受损进展为糖尿病的风险增大,且常合并一系列的心血管危险因子,致发生心血管疾病的危险性亦显著增加,糖耐量受损阶段心血管疾病的危险性已接近糖尿病。结论:糖耐量受损是心血管疾病的重要危险因子。有必要进一步研究及评估糖耐量受损阶段高血糖对机体的损害,早期采取干预措施,能降低及延缓心血管疾病的发生、进展。

关键词：糖耐量受损心血管疾病糖尿病综述文献

Heat addition to fluidized bed membrane reactors for hydrogen production

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Heat addition to fluidized bed membrane reactors for hydroge...

第九届全国氢能学术会议

作者： A.m.Adris j.R.Grace C.j.Lim membrane Reactor Technologies Ltd The University of British Columbia Canada

＜正＞Comparing to conventional fixed bed tubular reactors,fluidized bed membrane reactors show great potential for small to medium scale distributed hydrogen production,with the heat addition to sustain the endotherm...

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顶空色谱法测定土壤中氰和氰化氢残留量

土壤学报 2012年第6期49卷 1114-1119页

作者：李保同曾鑫年任永林 Desmarchelier j m 江西农业大学农学院南昌330045 华南农业大学农药与化学生物学教育部重点实验室广州510642 CSIRO Entomology GPO Box 1700Canberra ACT 2601Australia

氰(C2N2)是一种具有替代溴甲烷潜力的新熏蒸剂,建立土壤中C2N2及其降解产物氰化氢(HCN)的标准检测方法具有较重要的意义。本文采用溶剂顶空毛细管气相色谱-氮磷检测器(NPD)建立了熏蒸剂C2N2和HCN在土壤中的分析方法,优化了土壤中C2N2和... 详细信息

氰(C2N2)是一种具有替代溴甲烷潜力的新熏蒸剂,建立土壤中C2N2及其降解产物氰化氢(HCN)的标准检测方法具有较重要的意义。本文采用溶剂顶空毛细管气相色谱-氮磷检测器(NPD)建立了熏蒸剂C2N2和HCN在土壤中的分析方法,优化了土壤中C2N2和HCN预处理的顶空参数,并通过了方法的精密度、检出限和定量限等质量控制参数的验证实验。结果表明,用30%H2SO4溶液作提取溶剂、顶空平衡温度50℃和顶空平衡时间0.5 h为最佳的顶空方法参数;在0.1～10 mg kg-1的质量浓度范围内,C2N2和HCN的浓度与色谱峰面积线性相关系数均大于0.99。采用该方法测定土壤中C2N2和HCN的相对标准偏差(RSD)分别为4.58%和6.32%(n=5),检出限(LOD)分别为0.016 mg kg-1和0.028 mg kg-1(S/N=3),定量限(LOQ)分别为0.053 mg kg-1和0.093 mg kg-1(S/N=10)。该方法操作简单、灵敏度高、干扰少,适用于土壤中C2N2和HCN残留量的检测。

关键词：土壤氰(C2N2) 氰化氢(HCN) 熏蒸剂顶空气相色谱

Soil microbial community diversity and driving mechanisms

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Progress in Natural Science:materials International 2001年第11期11卷 20-26页

作者：夏北成 D.S.TREVES 周集中 j.m.TIEDjE Center for microbial Ecology China East Lansing Environmental Science Division Guangzhou 510275 Institute of Environmental Science mI 48824 michigan State University Oak Ridge National Laboratory TN 38831 USA Zhongshan University

To study the structure of soil microbial communities, DNA was extracted from different environmental soil samples, and 16S rDNA clone libraries were constructed. The diversity of these 16S libraries were analyzed with restriction fragment length polymorphism based on amplification ribosomal DNA restriction analysis ( RFLP-ARDRA) method. The results reveal a high diversity of the soil microbial communities, and striking differences in community structure at different depths. In the surface soil environment, there is no dominant gene pattern, but in the subsurface samples some dominant gene patterns are much more common. With the increasing depth the preference dominance becomes more significant. A spatial isolation hypothesis is proposed to explain the different community structures at different soil depths. microcosms are set to simulate competition between populations at different degrees of spatial isolation. These studies reveal that spatial isolation caused by low moisture affects the competitive in

关键词： soil microbe cloning community spatial isolation 16S rDNA.

Utilisation of Geothermal Heat Pumps within Permeable Pavements for Sustainable Energy and Water Practices

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journal of Energy and Power Engineering 2011年第2期5卷 122-128页

作者： K. Tota-maharaj.m. Scholz S.j. Coupe Institute for Infrastructure and Environment School of Engineering University of Edinburgh William Rankine Building TheKing＇s Buildings Edinburgh UK Hanson Formpave Tufihorn Avenue Coleford Gloucestershire UK

Geothermal heat pumps （GHPs） are an attractive proposition for renewable energy worldwide as it uses energy naturally stored in the earth. The Earth is a very resourceful form of energy, using the natural solar energy collection and heat storage capabilities as an infinite heat source/heat sink at the base of permeable pavements, which can provide excellent temperature gradients for GHP＇s. Experimental rigs were setup up at The University of Edinbttrgh for a combined permeable pavement and GHP system. At the base of a pavement structure （approximately 1 meter） below the ground＇s surface, temperatures are constant of 10℃ in the U.K all year round. The GHP performance efficiency was analysed by the coefficient of performance （COP） in a heating cycle and the energy efficiency ratio （EER） in a cooling cycle. The mean COP and EER for both systems averaged between 2-4.5 and 3-5 respectively. The combined GHP and pavement structure operated at an optimum efficiency for both heating and cooling cycles and has shown to be unaffected by higher summer or lower winter temperatures. This hybrid system is an attractive renewable energy technology and has additional environmental benefits such as urban runoff reuse and recycling.

关键词： Earth energy systems permeable pavements pervious pavements sustainable urban drainage (SUDS) thermo-geologic efficiency.

Template-based smoothing functions for data smoothing in Geodesy

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Geodesy and Geodynamics 2020年第4期11卷 300-306页

作者： m.Kiani Department of Geodesy University of TehranTehranIran

This paper is aimed at the derivation of a discrete data smoothing function for the discrete Dirichlet condition in a regular grid on the surface of a *** method employed here is the local L^2-seminorm minimization,through Euler-Lagrange method,for the Beltrami *** method results in a weighted average of the surrounding points in a te mplate based on the first order Taylor expansion of the unknown function under *** coefficients of the weighted average are calculated and used to smooth the Geoid height data in Iran,derived from the EGm2008 geopotential model.

关键词： minimization problem Regular grid Linear composition Beltrami operator Smoothing function