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Are Northeastern U.S. forests vulnerable to extreme drought?

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ecological Processes 2017年第1期6卷 351-363页

作者： Adam P.Coble Matthew A.Vadeboncoeur Z.Carter Berry Katie A.Jennings Cameron D.McIntire John l.Campbell lindsey e.Rustad Pamela H.Templer Heidi Asbjornsen Department of Natural Resources and the environment University of New Hampshire56 College Rd.114 James HallDurhamNH 03824USA. earth Systems Research Center University of New Hampshire8 College RoadDurhamNH 03824USA. Northern Research Station USDA Forest Service271 Mast RoadDurhamNH 03824USA. Department of Biology Boston University5 Cummington MallBostonMA 02215USA.

In the Northeastern U.S.,drought is expected to increase in frequency over the next century,and therefore,the responses of trees to drought are important to *** is recent debate about whether land-use change or moisture availability is the primary driver of changes in forest species composition in this *** argue that fire suppression from the early twentieth century to present has resulted in an increase in shade-tolerant and pyrophobic tree species that are drought intolerant,while others suggest precipitation variability as a major driver of species *** this debate,an emerging hypothesis is that mesophication and increases in the abundance of mesophytic genera(e.g.,Acer,Betula,and Fagus)resulted in forests that are more vulnerable to *** review examines the published literature and factors that contribute to drought vulnerability of Northeastern *** assessed two key concepts related to drought vulnerability,including drought tolerance(ability to survive drought)and sensitivity(short-term responses to drought),with a focus on Northeastern *** assessed drought-tolerance classifications for species,which revealed both consistencies and inconsistencies,as well as contradictions when compared to actual observations,such as higher mortality for drought-tolerant *** to drought sensitivity,recent work has focused on isohydric/anisohydric regulation of leaf water ***,based on the review of the literature,we conclude that drought sensitivity should be viewed in terms of multiple variables,including leaf abscission,stomatal sensitivity,turgor pressure,and dynamics of non-structural *** considered drought sensitive(e.g.,Acer,Betula,and liriodendron)may actually be less prone to drought-induced mortality and dieback than previously considered because stomatal regulation and leaf abscission in these species are effective at preventing water potential from reaching critica

关键词： Acer Betula Drought sensitivity Drought tolerance Quercus Northeastern U.S. Temperate deciduous

An XA21-Associated Kinase （OsSeRK2） Regulates Immunity Mediated by the XA21 and XA3 Immune Receptors

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Molecular Plant 2014年第5期7卷 874-892页

作者： Xuewei Chena Shimin Zuo Benjamin Schwessinger Mawsheng Chern Patrick e. Canlas Deling Ruan Xiaogang Zhou Jing Wang Arsalan Daudi Christopher J. Petzold Joshua l. Heazlewood Pamela C. Ronald Department of Plant Pathology and the Genome Center University of California Davis CA 95616 USA Rice Research Institute Sichuan Agricultural University Chengdu Sichuan 611130 China Joint Bioenergy Institute Emeryville CA 94710 USA Key laboratory of Crop Genetics and Physiology of Jiangsu Province Key Laboratory of Plant Functional Genomics of the Ministry of Education College of Agriculture Yangzhou University Yangzhou 225009 China

The rice XA21 immune receptor kinase and the structurally related XA3 receptor confer immunity to Xanthomonas oryzae pv. oryzae （Xoo）, the causal agent of bacterial leaf blight. Here we report the isolation of OsSeRK2 （rice somatic embryogenesis receptor kinase 2） and demonstrate that OsSeRK2 positively regulates immunity mediated by XA21 and XA3 as well as the rice immune receptor FlS2 （OsFlS2）. Rice plants silenced for OsSerk2 display altered morphology and reduced sensitivity to the hormone brassinolide. OsSeRK2 interacts with the intracellular domains of each immune receptor in the yeast two-hybrid system in a kinase activity-dependent manner. OsSeRK2 undergoes bidi- rectional transphosphorylation with XA21 in vitro and forms a constitutive complex with XA21 in vivo. These results demonstrate an essential role for OsSeRK2 in the function of three rice immune receptors and suggest that direct interaction with the rice immune receptors is critical for their function. Taken together, our findings suggest that the mechanism of OsSeRK2-meditated regulation of rice XA21, XA3, and FlS2 differs from that of AtSeRK3/BAK1-mediated regulation of Arabidopsis FlS2 and eFR.

关键词： immune receptor kinases somatic embryogenesis receptor kinase (SeRK) immunity Xanthomonas oryzae pv. oryzae rice.

Making Sense of Hospital Project MisPerformance: Over Budget, late, Time and Time Again—Why? And What Can Be Done About It?

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engineering 2022年第5期8卷 183-201页

作者： Peter e.D.love lavagnon A.Ika School of Civil and Mechanical engineering Curtin UniversityPerthWA 6845Australia Telfer School of Management University of OttawaOttawaON KIN 6N5Canada

Hospital projects worldwide often experience misperformance,showing a tendency to exceed their estimated cost,miss their deadline,suffer quality problems,and yield benefit *** this ubiquitous problem,this paper aims to make sense of this phenomenon by addressing the following research question:How can we make sense of hospital project misperformance,and what can be done to mitigate its occurrence?We use an illustrative case study approach and the analytical lens of sense-making to examine the misperformance of three mega-hospital *** research reveals issues such as scope changes,an inability to adapt and respond to risk and uncertainty,ineffectual project management and governance,and optimism bias,which combine to impact project performance *** suggest that the two prominent theoretical perspectives dominating the literature in this field fall short of adequately explaining hospital project *** provide suggestions for improving the procurement process of hospitals and submit there is a need to develop a robust and balanced theory of project misperformance.

关键词： Cost Hospital Optimism bias Procurement Project management Performance Sense-making

Diagenetic and Reservoir Quality Variation of Miocene Sandstone Reservoir Analogues from Three Basins of Southern California,USA

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Journal of earth Science 2020年第5期31卷 930-949页

作者： Sunday e.Okunuwadje David MacDonald Stephen Bowden School of Geosciences University of AberdeenAberdeen AB243UEUK Department of Geology University of BeninBenin City PMB 1154Nigeria

The Miocene sandstone deposits in the Southern California region are important hydrocarbon reservoirs. However, their development has been very challenging due to the wide variability in their reservoir quality. These sandstones have been studied from three sedimentary basins by petrographic thin section, scanning electron microscope, and X-ray diffraction to evaluate and compare the influence of diagenesis on their reservoir quality in these basins. Four petrofacies, namely P1(sand injectite or dyke), P2(sub-marine fan), P3(turbidite and marine-influenced alluvial fans) and P4(continental sandstones) have been identified. P1 and P2 characterise the sandstones in the San Joaquin forearc basin and are affected by kaolinite and extensive early calcite diagenesis. P3 and P4 delineate the sandstones in the Cajon Valley and Salton Trough strike-slip basins and are dominated by smectite, mixed illite-smectite, early calcite and late calcite diagenesis. early calcite cement in P3 and P4 is in lower proportion than in P1 and P2. Although the dissolution of these sandstones by acidic fluids did not have a pattern, it, however, has the most considerable influence on P2 creating moldic pores which are expected to increase pore connectivity. The relatively abundant dissolution pores in P2, together with the absence of late authigenic calcite and illite clay in comparison to the other petrofacies studied are likely to make this sandstone facies the best reservoir targets in the Southern California region. These rocks are analogous to producing reservoirs in the region. However, because, petroleum accumulation in these reservoirs are compartmentalized by early calcite cement, maximum recovery using acidified fluids is recommended to dissolve the calcite-filled pores in order to increase connectivity of their pore network and enhance flow potential.

关键词： diagenesis petrofacies reservoir quality Miocene California

Ground motion spatial variability effects on seismic response control of cable-stayed bridges

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earthquake engineering and engineering Vibration 2011年第1期10卷 37-49页

作者： Shehata e. Abdel Raheem Toshiro Hayashikawa Uwe Dorka Civil engineering Department Faculty of Engineering Assiut University Bridge and Structural Design engineering Hokkaido University Steel & Composite Structures Kassel Universitt

The spatial variability of input ground motion at supporting foundations plays a key role in the structural response of cable-stayed bridges （CSBs）; therefore, spatial variation effects should be included in the analysis and design of effective vibration control systems. The control of CSBs represents a challenging and unique problem, with many complexities in modeling, control design and implementation, since the control system should be designed not only to mitigate the dynamic component of the structural response but also to counteract the effects of the pseudo-static component of the response. The spatial variability effects on the feasibility and efficiency of seismic control systems for the vibration control of CSBs are investigated in this paper. The assumption of uniform earthquake motion along the entire bridge may result in quantitative and qualitative differences in seismic response as compared with those produced by uniform motion at all supports. A systematic comparison of passive and active system performance in reducing the structural responses is performed, focusing on the effect of the spatially varying earthquake ground motion on the seismic response of a benchmark CSB model with different control strategies, and demonstrates the importance of accounting for the spatial variability of excitations.

关键词： cable-stayed bridge vibration control earthquake spatial variation seismic design semi-active control

Determination of nitrogen reduction levels necessary to reach groundwater quality targets in Slovenia

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Journal of environmental Sciences 2014年第9期26卷 1806-1817页

作者： Miso Andelov Ralf Kunkel Jo?e Uhan Frank Wendland Slovenian environment Agency Hydrogeological Analysis DivisionVojkova 1bSI-1000 LjubljanaSlovenia Forschungszentrum Jülich (FZJ) Institute of Bio- and Geosciences (IBG)Institute 3: Agrosphere52425 JuelichGermany

Within a collaborative project between Slovenian environment Agency （ARSO） and Research Center Jfilich （FZJ）, nitrogen reduction levels necessary to reach groundwater quality targets in Slovenia were assessed. For this purpose the hydrological model GROWA- DeNUZ was coupled with agricultural N balances and applied consistently to the whole territory of Slovenia in a spatial resolution of 100 x 100 m. GROWA was used to determine the water balance in Slovenia for the hydrologic period 1971-2000. Simultaneously, the displaceable N load in soft was assessed from agricultural Slovenian N surpluses for 2011 and the atmospheric N deposition. Subsequently, the DeNUZ model was used to assess the nitrate degradation in soil and, in combination with the percolation water rates from the GROWA model, to determine nitrate concentration in the leachate. The areas showing predicted nitrate concentrations in the leachate above the eU groundwater quality standard of 50 mg NO3/l have been identified as priority areas for implementing nitrogen reduction measures. For these ＂hot spot＂ areas DeNUZ was used in a backward mode to quantify the maximal permissible nitrogen surplus levels in agriculture to guarantee a nitrate concentration in percolation water below 50 mg NO3/l. Model results indicate that additional N reduction measures should be implemented in priority areas rather than area-covering. Research work will directly support the implementation of the european Union Water Framework Directive in Slovenia, e.g., by using the maximal permissible nitrogen surplus levels as a framework for the derivation of regionally adapted and hence effective nitrogen reduction measures.

关键词： eU Water Framework DirectiveGroundwater quality targetsNitrate pollutionReactive nitrate transport modeling

exact solution and dynamic buckling analysis of a beam-column system having the elliptic type loading

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Applied Mathematics and Mechanics(english edition) 2010年第10期31卷 1317-1324页

作者： H.S.ARTeM l.AYDIN Department of Mechanical engineering Izmir Institute of Technology

This paper presents a closed form solution to the dynamic stability problem of a beam-column system with hinged ends loaded by an axial periodically time-varying compressive force of an elliptic type,i.e.,a1cn 2（τ,k 2）＋a2sn 2（τ,k 2）＋a3dn 2（τ,k 2）.The solution to the governing equation is obtained in the form of Fourier sine *** resulting ordinary differential equation is solved *** the exact analytical solutions to the dynamic buckling problems is ***,the availability of exact solutions can provide adequate understanding for the physical characteristics of the *** this study,the frequency-response characteristics of the system,the effects of the static load,the driving forces,and the frequency ratio on the critical buckling load are also investigated.

关键词： dynamic buckling exact solution stability-instability Jacobi elliptic functions

Plasticity of Xyloglucan Composition in Bean （Phaseolus vulgaris）-Cultured Cells during Habituation and Dehabituation to lethal Concentrations of Dichlobenil

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Molecular Plant 2010年第3期3卷 603-609页

作者： A. Alonso-Simon l. Neumetzler R Garcia-Angulo A.e. encina J.l. Acebes J.M. Alvarez T. Hayashi Area de Fisiologia Vegetal Universidad de Leon E-24071 Leon Spain Max Planck Institute of Molecular Plant Physiology 14476 Golm Germany Kyoto University RISH Gokasho Uji Kyoto 611-0011 Japan

Bean cells that have been habituated to grow in a lethal concentration （12 μM） of 2,6-dichlorobenzonitrile （dichlobenil or DCB, a cellulose biosynthesis inhibitor） are known to have decreased cellulose content in their cell walls. Xyloglucan, which is bound to cellulose and together with it forms the main loading network of plant cell walls, has also been described to decrease in habituated cells, but whether the change on cellulose affects the xyloglucan structure besides its abundance has not been analyzed. Fragmentation analysis with xyloglucan-specific endoglucanase （XeG） and endocellulase revealed that habituation to DCB caused a change in the fine structure of xyloglucan, namely a decrease in fucosyl residues attached to the galactosyl-xylosyl residues along the glucan backbone. After the removal of herbicide from the medium （dehabituated cells）, xyloglucan recovered its fucosyl residues. In addition, some cello-oligosaccharides could be detected only in habituated cells＇ xyloglucan digested by XeG and endocellulase, corresponding to a glucan co- valently bound or co-precipitated with the hemicelluloses. These results show that structural flexibility of cell walls relies in part on the plasticity of xyloglucan composition and opens up new perspectives to further research in this field.

关键词： Bean 2,6-dichlorobenzonitrile habituation and dehabituation OlIMP (Oligosaccharides Mass Profiling) xyloglucan.

维生素D与儿童青少年心理健康相关性的研究进展

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中国学校卫生 2024年第7期45卷 1055-1058,1064页

作者：王吕珧徐保玉汤婷王君苏普玉汪耿夫安徽医科大学公共卫生学院妇幼保健医学系合肥230032 安徽医科大学预防医学专业安徽医科大公共卫生学院儿少卫生与妇幼保健学系/出生人口健康教育部重点实验室/人口健康与优生安徽省重点实验室

维生素D(Vit D)作为一种重要的营养素,在儿童青少年生长发育过程中的重要作用已被广泛认可,但其与心理健康之间的关联仍处于探索阶段。通过回顾与总结国内外Vit D对儿童青少年常见心理健康问题影响的相关研究,包括抑郁症状、焦虑症状、... 详细信息

维生素D(Vit D)作为一种重要的营养素,在儿童青少年生长发育过程中的重要作用已被广泛认可,但其与心理健康之间的关联仍处于探索阶段。通过回顾与总结国内外Vit D对儿童青少年常见心理健康问题影响的相关研究,包括抑郁症状、焦虑症状、自杀相关心理行为,以及Vit D影响心理健康的生物学机制等,旨在为改善中国儿童青少年心理健康和开展未来研究提供科学依据与思路。

关键词：维生素D 精神卫生儿童青少年

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