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Characterizing drought in California:new drought indices and scenario-testing in support of resource management

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ecological Processes 2018年第1期7卷 1-13页

作者： Lorraine e.Flint Alan L.Flint John Mendoza Julie Kalansky F.M.Ralph U.S.Geological Survey 6000 J.StSacramentoCA 95819USA Sonoma County Water Agency 404 Aviation Dr.Santa RosaCA 95403USA Scripps Institution of Oceanography 9500 Gilman Dr.La JollaCA 92093USA

Introduction:California’s recent drought(2012–2016)has implications throughout the state for natural resource management and adaptation planning and has generated many discussions about drought characterization and *** study characterizes drought conditions with two indices describing deficits in natural water supply and increases in landscape stress developed on the basis of water balance modeling,at a fine spatial scale to assess the variation in conditions across the entire state,and provides an in-depth evaluation for the Russian River basin in northern California to address local resource management by developing extreme drought scenarios for consideration in planning and ***:We employed the USGS Basin Characterization Model to characterize drought on the basis of water supply(a measure of recharge plus runoff)and landscape stress(climatic water deficit).These were applied to the state and to the Russian River basin where antecedent soil moisture conditions were evaluated and extreme drought scenarios were developed and run through a water management and reservoir operations model to further explore impacts on water ***:Drought indices indicated that as of the end of water year 2016 when reservoirs were full,additional water supply and landscape replenishment of up to three average years of precipitation in some locations was needed to return to normal *** soil conditions in the Russian River were determined to contribute to very different water supply results for different years and were necessary to understand to anticipate proper watershed response to *** drought scenarios manifested very different kinds of drought and recovery and characterization helps to guide the management response to ***:These scenarios and indices illustrate how droughts differ with regard to water supply and landscape stress and how long warm droughts recover much more slowly than short very dry dro

关键词： California drought Russian River Water supply Basin Characterization Model

Fatigue crack initiation of magnesium alloys under elastic stress amplitudes:A review

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Frontiers of Mechanical engineering 2019年第1期14卷 113-127页

作者： B.J.WANG D.K.XU S.D.WANG e.H.HAN School of environmental and Chemical engineering Shenyang Ligong UniversityShenyang 110159China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The most advantageous property of magnesium(Mg)alloys is their density,which is lower compared with traditional metallic *** alloys,considered the lightest metallic structural material among others,have great potential for applications as secondary load components in the transportation and aerospace *** fatigue evaluation of Mg alloys under elastic stress amplitudes is very important in ensuring their service safety and *** their hexagonal close packed structure,the fatigue crack initiation of Mg and its alloys is closely related to the deformation mechanisms of twiuning and basal ***,for Mg alloys with shrinkage porosities and inclusions,fatigue cracks will preferentially initiate at these defects,remarkably reducing the fatigue *** this paper,some fundamental aspects about the fatigue crack initiation mechanisms of Mg alloys are reviewed,in cluding the 3 followings:1)Fatigue crack initiation of as-cast Mg alloys,2)influence of microstructure on fatigue crack initiation of wrought Mg alloys,and 3)the effect of heat treatment on fatigue initiation ***,some unresolved issues and future target on the fatigue crack initiation mechanism of Mg alloys are also described.

关键词： Mg alloys fatigue behavior microstructure crack initiation deformation mechanism

ZmGns,a maize class I β-1,3-glucanase,is induced by biotic stresses and possesses strong antimicrobial activity

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Journal of Integrative Plant Biology 2015年第3期57卷 271-283页

作者： Yu-Rong Xie Yenjit Raruang Zhi-Yuan Chen Robert L.Brown Thomas e.Cleveland Department of Plant Pathology and Crop Physiology Louisiana State University Agricultural Center Biotechnology Research Institute the Chinese Academy of Agricultural Sciences Southern Regional Research Center USDA-ARS

Plant b-1,3-glucanases are members of the pathogenesis-related protein 2（PR-2） family,which is one of the 17 PR protein families and plays important roles in biotic and abiotic stress *** of the differentially expressed proteins（spot 842） identified in a recent proteomic comparison between five pairs of closely related maize（Zea mays L.） lines differing in aflatoxin resistance was further investigated in the present ***,the corresponding cDNA was cloned from maize and designated as *** encodes a protein of338 amino acids containing a potential signal *** expression of Zm Gns was detectible in all tissues studied with the highest level in *** was significantly induced by biotic stresses including three bacteria and the fungus Aspergillus *** was also induced by most abiotic stresses tested and growth hormones including salicylic *** vivo,ZmGns showed a significant inhibitory activity against thebacterial pathogen Pseudomonas syringae *** DC3000 and fungal pathogen Botrytis cinerea when it overexpressed in *** high level of expression in the silk tissue and its induced expression by phytohormone treatment,as well as by bacterial and fungal infections,suggest it plays a complex role in maize growth,development,and defense.

关键词： β-1 3-Glucanase biological activity expression profiles Zea mays ZmGns

On Solving the （2＋1）-Dimensional Nonlinear Cubic-Quintic Ginzburg-Landau equation Using Five Different Techniques

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Journal of Partial Differential equations 2018年第2期31卷 97-118页

作者： ZAYeD elsayed M. e. Al-NOWeHY A.-G. eLSHATeR Mona e. M. Mathematics Department Faculty of Sciences Zagazig University P. O. Box 44519Zagazig Egypt. Mathematics Department Faculty of Education and Science Taiz University TaizYemen.

In this article, we apply five different techniques, namely the （G//G）-expansion method, an auxiliary equation method, the modified simple equation method, the first integral method and the Riccati equation method for constructing many new exact solutions with parameters as well as the bright-dark, singular and other soliton solutions of the （2＋1）-dimensional nonlinear cubic-quintic Ginzburg-Landau equation. Comparing the solutions of this nonlinear equation together with each other are presented. Comparing our new results obtained in this article with the well-known results are given too.

关键词： (G'/G)-expansion method auxiliary equation method modified simple equation method first integral method Riccati equation method exact traveling wave solutions solitary wave solutions Cubic-quintic Ginzburg-Landau equation.

早期干预对NICU早产儿体格及神经心理发育的效果研究

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中国妇幼健康研究 2024年第4期35卷 25-31页

作者：孔锐陆晓婷宋媛叶侃戴月娥南京医科大学附属苏州医院儿童保健科江苏苏州215008

目的探讨早期干预对于新生儿重症监护病房(NICU)早产儿两年内的体格和神经心理发育的影响。方法选取2018年1月至2020年12月于苏州市立医院就诊的102例NICU早产儿为干预组,随机抽取105例同期健康足月儿为对照组。结果矫正24月龄时,经... 详细信息

目的探讨早期干预对于新生儿重症监护病房(NICU)早产儿两年内的体格和神经心理发育的影响。方法选取2018年1月至2020年12月于苏州市立医院就诊的102例NICU早产儿为干预组,随机抽取105例同期健康足月儿为对照组。结果矫正24月龄时,经早期干预的低危早产儿体重、身长以及头围的Z评分均可达到正常足月儿水平(分别为0.34±0.98、0.40±1.30和0.54±1.04,P>0.05),但是高危早产儿组的3项Z评分不及足月儿组(分别为-0.17±1.15、0.00±1.29和-0.33±1.24,P0.05)。语言与社交行为方面,矫正18~24月龄,早产儿的发育水平可达足月儿水平。适应能力发育方面,矫正18月龄前,高危、低危早产儿适应能力水平可达足月儿,但24月龄时,早产儿适应能力水平均不及足月儿,高危儿组、低危儿组、足月儿组分别为102.77±12.04、101.73±10.34、106.78±9.31(P<0.05)。与之类似的精细运动发育,矫正12月龄时,高危、低危早产儿精细运动水平可达足月儿,18~24月龄时,高危、低危早产儿精细运动水平均不及足月儿。结论出生后2年内高危和低危早产儿体格及神经心理发育存在差异,且高危早产儿落后尤其明显。正确认识早产儿体格及神经心理发育规律,制定个体化的早期干预模式,对早产儿的体格及神经心理发育具有重要作用。

关键词：早产儿体格发育神经心理发育早期干预

Vacuum promotes metabolic shifts and increases biogenic hydrogen production in dark fermentation systems

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Frontiers of environmental Science & engineering 2016年第3期10卷 513-521页

作者： Haifa RAJHI Daniel PUYOL Mirna C. MARTiNeZ emiliano e. DLAZ Jose L. SANZ Department of Molecular Biology University Autonoma of Madrid Madrid 28049 Spain Section of Chemical engineering University Autonoma of Madrid Madrid 28049 Spain MYGeN Laboratory Cantoblanco Madrid 28049 Spain

The successful operation of any type of hydrogen-producing bioreactor depends on the performance of the microorganisms present in the system. Both substrate and partial gas pressures are crucial factors affecting dark fermentation metabolic pathways. The main objective of this study was to evaluate the impact of both factors on hydrogen production using anaerobic granular sludge as inoculum and, secondly, to study the metabolic shifts of an anaerobic community subjected to low partial gas pressures. With this goal in mind, seven different wastewater （four synthetic media, two industrial waste- water, and one domestic effluent） and the effect of applying vacuum on the systems were analyzed. The application of vacuum promoted an increase in the diversity of hydrogen-producing bacteria, such as Clostridium, and promoted the dominance of acetoclasticover hydrogenotrophic methanogens. The application of different media promoted a wide variety of metabolic pathways. Nevertheless, reduction of the hydrogen partial pressure by application of vacuum lead to further oxidation of reaction intermediates irrespective of the medium used, which resulted in higher hydrogen and methane production, and improved the COD removal. Interestingly, vacuum greatly promoted biogenic hydrogen production from a real wastewater, which opens possibilities for future application of dark fermentation systems to enhance biohydrogen yields.

关键词： dark fermentation biohydrogen wastewaters vacuum

A Double Crown Hexakis[(Di-µ-benzylthio)Nickel]Cluster:Synthesis,Structure and Properties

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Chinese Journal of Structural Chemistry 2022年第3期41卷 40-46,I0008页

作者： LIU e JIA Ai-Quan ZHANG Qian-Feng JIAN Fang-Fang Institute of Molecular engineering and Applied Chemistry Anhui University of TechnologyMa’anshanAnhui 243002China School of Chemical engineering and Pharmaceutics Henan University of Science and TechnologyLuoyang 471000China

The double crown hexakis[(di-μ-benzylthio)nickel]cluster,[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]·C_(2)H_(5)OH,was obtained by reacting C_(6)H_(5)CH_(2)SNa with[(CH_(3))_(2)CHOCS_(2)]_(2)Ni in *** results of electrochemical studies show that[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]is a quasi-reversible *** crystal structure of[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]·C_(2)H_(5)OH is composed of discrete[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]and C_(2)H_(5)OH solvent *** Ni atom is surrounded by four S atoms of theµ2-SCH_(2)C_(6)H_(5)ligands in a distorted square-planar *** C_(6)H_(5)CH_(2)S-side chains are arranged in the axial and equatorial positions,alternately,concerning the pseudo-hexagonal axis of the ***π-πand C-H···πeffects form the supramolecular nano-channel along the a-axis in the crystal,which wraps the solvent ethanol molecules in *** addition,a wall is formed along the b-and c-axes,so that the ethanol molecules can freely enter and leave along the *** effects result in the ability of the title compound to adsorb and desorb ethanol *** analysis and powder X-ray diffraction at different temperature are provided to demonstrate this point.

关键词： benzylthiol nickel cluster porous materials cyclic voltammetry thermogravimetry

Natural history of Barrett's esophagus

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World Journal of Gastroenterology 2012年第27期18卷 3483-3491页

作者： Rao Milind Stephen e Attwood Department of Surgery North Tyneside General HospitalNorth ShieldsTyne and Wear NE29 8NHUnited Kingdom

The natural history of Barrett's esophagus (Be) is difficult to quantify because,by definition,it should describe the course of the condition if left ***,we assume that patients with Be will receive symptomatic treatment with acid suppression,usually a proton pump inhibitor,to treat their *** paper describes the development of complications of stricture,ulcer,dysplasia and adenocarcinoma from this *** over the definition of Be and its implications in clinical practice are *** presence of intestinal metaplasia and its relevance to cancer risk is discussed,and the need to measure the extent of the Barrett's epithelium (long and short segments) using the Prague guidelines is *** and international consensus over the diagnosis and management of Be are being regularly *** need for expert consensus is important due to the lack of randomized trials in this *** searching the literature,we have tried to collate the important studies regarding progression of Barrett's to dysplasia and *** therapeutic studies yet reported show a clear reduction in the development of cancer in *** effect of pharmacological and surgical intervention on the natural history of Barrett's is a subject of ongoing research,including the Barrett's Oesophagus Surveillance Study and the aspirin and esomeprazole cancer chemoprevention trial with interesting *** geographical variation and the wide range of outcomes highlight the difficulty of providing an individualized risk profile to patients with *** studies on the interaction of genome wide abnormalities in Barrett's and their interaction with environmental factors may allow individualization of the risk of cancer developing in Be.

关键词： Barrett's esophagus Columnar lined esoph-agus Dysplasia Adenocarcinoma Gastroesophagealreflux Surgery

Fragmentation patterns and systematic transitions of the forested landscape in the upper Amazon region, ecuador 1990-2008

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Journal of Forestry Research 2014年第2期25卷 301-309页

作者： Santiago Bonilla-Bedoya Juan R.Molina José e.Macedo-Pezzopane Miguel A.Herrera-Machuca DepartaTento de Ingeniería Forestal E.T.S.I.A.M.Universidad de CórdobaCaTpus de Excelencia Internacional Agroali Tentario (ceiA3) Secretaria Nacional de educación Superior CienciaTecnología e Innovación del EcuadorWhy Tper E7-37 y Alpallana Quito. Ecuador Departa Tento de engenharia Florestal Universidade Federal do espírito Santo

The analysis of the systematic transitions in the forested landscape and the study of the forest fragmentation patterns allow us to deepen our understanding of the changes in the vegetation ground cover. The importance of knowing the intricate patterns of the land usage of the upper basin of the Amazon region is widely recognized. This zone is one of the most diverse biological areas in the world, is home to large areas of mature tropical cloud forest and demonstrates high probabilities of stable climatic conditions in light of global warming. The research quan- tiffed systematic transitions through the ＂loss＂ and ＂gain＂ of the different categories of landscape during the eighteen-year study period of the ecuadorian Amazon Region （eAR）, the forest fragmentation patterns were also analyzed based on a set of indicators. Therefore, with respect to the entirety of the landscape, the results registered for the ground coverage in forested areas during the first period （1990-2000）, show a decrease of 6.99% and an increase of 0.68%; and during the second period （2000-2008）, show a decrease of 3.99% and an increase of 2.14%. It demonstrated that forest and agricultural areas tended to replace or be replaced by herbaceous vegetation faster than expected fortuitously. Finally, the indices of fragmentation signaled intense changes during the 1990-2000 period with a reduction during the period 2000-2008. Per- centages registered in the Largest Patch Index （LPI） were between 79.58%; 52.39% and 49.99% respectively; while the Patch Density （PD） varied between 0.04; 0.06 and 0.07. This suggests the propensity of for- est cover to remain intact. The results of this investigation suggest a tendency towards stability in ecuador＇s Amazon landscape. Within the framework for development and management of this area, the tendency is natural regeneration. This permits a consolidation of the conservation, reforestation, forestation and agricultural forestry plans, programs and systems for the

关键词： ecuadorian Amazon systematic transitions fragmentation natural regeneration