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The role of soluble sugars during drought in tropical tree seedlings with contrasting tolerances

Journal of Plant Ecology 2020年第4期13卷 389-397页

作者： michael J.O’Brien Annabelle Valtat Samuel Abiven Mirjam S.Studer robert Ong Bernhard Schmid Área de Biodiversidad y Conservación Universidad Rey Juan Carlosc/Tulipán s/n.E-28933 MóstolesMadridSpain Southeast Asia rainforest research Partnership The Peak VistaLorang Punjak 1Tanjung LipatKota KinabaluSabah 88400Malaysia Department of Evolutionary Biology and Environmental Studies University of ZurichWinterthurerstrasse 1908057 ZurichSwitzerland Department of Geography University of ZurichWinterthurerstrasse 1908057 ZurichSwitzerland Laboratoire de Géologie UMR 8538Ecole Normale SupérieurePSL Research UniversityCNRSParisFrance Centre de recherche enécologie expérimentale et prédictive(CErEEP-Ecotron IleDeFrance) Département de biologieEcole normale supérieureCNRSPSL University77140St-Pierre-les-NemoursFrance Forest research Centre Sepilok90715 SandakanSabahMalaysia

Aims Non-structural carbohydrates(NSCs)are plant storage compounds used for metabolism,transport,osmoregulation and regrowth following the loss of plant *** in conditions suitable for optimal growth,plants continue to store *** storage may be due to passive accumulation from sink-inhibited growth or active reserves that come at the expense of *** former pathway implies that NSCs may be a by-product of sink limitation,while the latter suggests a functional role of NSCs for use during poor *** Using 13C pulse labelling,we traced the source of soluble sugars in stem and root organs during drought and everwet conditions for seedlings of two tropical tree species that differ in drought tolerance to estimate the relative allocation of NSCs stored prior to drought versus NSCs assimilated during *** monitored growth,stomatal conductance,stem water potential and NSC storage to assess a broad carbon response to *** Findings We found that the drought-sensitive species had reduced growth,conserved NSC concentrations in leaf,stem and root organs and had a larger proportion of soluble sugars in stem and root organs that originated from pre-drought storage relative to seedlings in control *** contrast,the drought-tolerant species maintained growth and stem and root NSC concentrations but had reduced leaf NSCs concentrations with a larger proportion of stem and root soluble sugars originated from freshly assimilated photosynthates relative to control *** results suggest the drought-sensitive species passively accumulated NSCs during water deficit due to growth inhibition,while the drought-tolerant species actively responded to water deficit by allocating NSCs to stem and root *** strategies seem correlated with baseline maximum growth rates,which supports previous research suggesting a trade-off between growth and drought tolerance while providing new evidence for the importance of plasticity in

关键词： ^(13)C labelling carbohydrate storage drought tolerance hydraulic function Shorea parvifolia Shorea beccariana source–sink allocation

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Monsoon Subdiyisional rainfall Dimensionality and Predictability

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Advances in Atmospheric Sciences 1991年第3期8卷 351-356页

作者： J.r.Kulkarni Indian Institute of Tropical meteorology Pune-411008 India

For summer monsoon rainfall purpose India is divided into 35 *** daily rainfall series of one such subdivision(Konkan)has been analysed using the phase space *** years(1959-1973)of daily rainfall data have been utilised in this *** shows that the variability is due to the existing of strange attractor of dimension about *** predictability is estimated by computing the Lyapunov characteristic *** computations show that the predictability is about 8 days.

关键词： Daily rainfall Indian Summer Monsoon East Asian Summer Monsoon Strange Attractor Indian Summer Monsoon rainfall

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Mind the Gap

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China International Business 2006年第4期 16-21页

作者： michael O＇NEILL

Over the last 12 months, influential voices both inside and outside of central government have been expressing concern over increasing wealth inequality. After more than two decades of fast economic growth, characterized by a get-rich-quick philosophy, politicians and policy makers have begun the important move towards guaranteeing that the benefits of development are shared by all sectors of society. Central to this objective will be finding adequate solutions to one of the biggest problems to emerge from the country＇s economic miracle： the widening income gap. This month, CIB looks into the growing concern of wealth inequality and asks four experts how they think the problem can best be solved.

关键词：中国贫富差距和谐社会城乡差距居民收入

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Development of a rarefaction wave at discharge initiation in a storage silo--DEM simulations

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Particuology 2018年第1期16卷 37-49页

作者： r. Kobylka J. Horabik M. Molenda Institute of Agrophysics Polish Academy of Sciences ul. Doswiadczalna 4 20-290 Lublin Poland

The generation of a rarefaction wave at the initiation of discharge from a storage silo is a phenomenon of scientific and practical interest. The effect, sometimes termed the dynamic pressure switch, may create dangerous pulsations of the storage structure. Owing to the nonlinearity, discontinuity, and heterogeneity of granular systems, the mechanism of generation and propagation of stress waves is complex and not yet completely understood. The present study conducted discrete element simulations to model the formation and propagation of a rarefaction wave in a granular material contained in a silo. Modeling was performed for a flat-bottom cylindrical container with diameter of 0.1 or 0.12 m and height of 0.5 m. The effects of the orifice size and the shape of the initial discharging impulse on the shape and extent of the rarefaction wave were examined. Positions, velocities, and forces of particles were recorded every 10-5 s and used to infer the location of the front of the rarefaction wave and loads on construction members. Discharge through the entire bottom of the bin generates a plane rarefaction wave that may be followed by a compaction wave, depending on the discharge rate. Discharge through the orifice generates a spherical rarefaction wave that, after reflection from the silo wall, travels up the silo as a sequence of rarefaction-compaction cycles with constant wavelength equal to the silo diameter, During the travel of the wave along the bin height, the wave amplitude increases with the distance traveled. Simulations confirmed earlier findings of laboratory and numerical （finite element method） experiments and a theoretical approach, estimating the speed of the front of the rarefaction wave to range from 70 to 80 m/s and the speed of the tail to range from 20 to 60 m/s.

关键词： Granular flow Dynamic pressure switch Discrete element method Silo discharge Stress wave rarefaction wave

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On the Forcing of the radial-vertical Circulation within Cyclones-Part 1: Concepts and Equations

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Advances in Atmospheric Sciences 1998年第3期15卷 64-85页

作者： D.r.Johnson Space Science and Engineering Center University of Wisconsin-Madison Madison USA

お? Following the theoretical result of Eliassen, the Sawyer-Eliassen equation for frontal circulations and the equation for forcing the meridional circulation within a circumpolar vortex are extended in isentropic coordinates to describe the forcing of the azimuthally averaged mass-weighted radial-vertical circulation within translating extratropical and tropical cyclones. Several physical processes which are not evident in studies employing isobaric coordinates are isolated in this isentropic study. These processes include the effects of pressure torque, inertial torque and storm translation that are associated with the asymmetric structure in isentropic coordinates. This isentropic study also includes the effects of eddy angular momentum transport, diabatic heating and frictional torque that are common in both isentropic and isobaric studies. All of the processes are modulated by static, inertial and baroclinic stabilities.  Consistent with the theoretical result of Eliassen, the numerical solution from this isentropic study shows that the roles of torque, diabatic heating and hydrodynamic stability in forcing the radial-vertical circulation within stable vortices are that 1) positive (negative) torque which results in the counterclockwise (clockwise) rotation of vortices also forces the outflow (inflow) branch of the radial-vertical circulation, 2) diabatic heating (cooling) forces the ascent (descent) branch of the radial-vertical circulation and 3) for given forcing, the weaker hydrodynamic stability results in a stronger radial-vertical circulation. It is the net inflow or convergence (net outflow or divergence), vertical motions and the associated redistribution of properties that favor the evolution of vortices with colorful weather events.  Numerical solutions of this isentropic study are given in companion articles. The relatively important contribution of various physical processes to the forcing of the azimuthally-averaged mass-weighted radial-

关键词： The forcing of the radial-vertical circulation Quasi-Lagrangian diagnostics of cyclones,Balanced equation

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An Overview on Biological Markers in reproductive and Developmental Toxicology: Concepts, Definitions and Use in risk Assessment

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Biomedical and Environmental Sciences 1991年第1期4卷 8-34页

作者： DONALD r.MATTISON Graduate School of Public Health University of Pittsburgh Pittsburgh

reproduction and development are complex couple-dependent processes. risk assessment for these health outcomes requires the use of biomarkers to link exposures to disease. Biological markers of susceptability, external dose, internal dose, biologically effective dose, early or late biological responses, altered reproductive or developmental function, and reproductive or developmental disease are introduced. Using these biomarkers it is possible to define a biologically based risk assessment methodology for reproductive and developmental toxicity. risk assessment for reproductive toxicity requires definition of male and female fecundity, couple-specific factors, spontaneous abortion, rate, and other factors. Using using sperm count as a biomarker for male fecundity, an example of a reproductive risk assessment using biomarkers is performed.

关键词： An Overview on Biological Markers in reproductive and Developmental Toxicology Concepts Definitions and Use in risk Assessment

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Broaching Political and Theoretical Divides through Deliberation

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Journal of Philosophy Study 2011年第5期1卷 334-343页

作者： michael Da Silva University of Toronto

Commitment to deliberative democracy as a tool for social and political ordering is shared by political philosophers from many traditions. This paper examines John rawls and Iris Marion Young＇s respective commitments to deliberative democracy in hopes of finding a methodological proposal for peace between followers of rawls, the greatest liberal political philosopher of the 20th century, and Young, the late anti-liberal and anti-oppression theorist. While there are important differences between their respective positions, this paper posits that deliberative democracy can appease adherents of both thinkers, providing a shared method for determining conflicts between them. Liberal democracy is preferable, partly since it creates a place for anti-liberal positions （viz., Young＇s position can exist within the larger rawlsian framework）, but deliberative democracy can succeed even if one is not a liberal democrat.

关键词： social and political philosophy deliberative democracy John rawls Iris Marion Young

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基于re3data的科研数据仓储全景分析

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图书情报工作 2017年第22期61卷 69-76页

作者：王辉 michael Witt 中国科学院文献情报中心北京100190 中国科学院大学北京100049 美国普渡大学图书馆西拉法叶47907

[目的/意义]基于re3data元数据对科研数据仓储进行背景、政策、学科、内容、服务、访问、技术支持等分析,揭示科研数据仓储在学科间的差异,从多角度呈现科研数据仓储的全景。[方法/过程]从re3data元数据中遴选14个指标,对1 848个科研数... 详细信息

[目的/意义]基于re3data元数据对科研数据仓储进行背景、政策、学科、内容、服务、访问、技术支持等分析,揭示科研数据仓储在学科间的差异,从多角度呈现科研数据仓储的全景。[方法/过程]从re3data元数据中遴选14个指标,对1 848个科研数据仓储的责任机构进行定量分析,并采用独立样本t检验分析数据内容、服务类型、数据访问与上传等在学科间的差异情况。[结果/结论]大部分科研数据仓储是非营利组织负责的,机构主要提供基金资助、技术支持和一般维护。目前登记的科研数据仓储主要来自欧美国家及国际组织。科研数据仓储的类型主要以学科为主,生命科学和自然科学的仓储数量最多。科研数据仓储的数据内容类型、服务类型、数据开放程度、应用编程接口在学科间存在显著差异。

关键词：科研数据仓储统计分析元数据开放获取

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Influence of Potassium Fertilization on Yield and Quality of Foliar Vegetable Crops

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Pedosphere 2001年第1期11卷 77-82页

作者： NIWUZHONG r.HArDTEr CollegeofEnvironmentandresourceSciences ZhejiangUniversityHangzhou310029（China） InternationalPotashInstitute c／oKaliundSalzGmbH.P.O.Box102029D－34111Kassel（Germany）

Over a period of two years , field experiments were conducted on four silty loam soils grown with foliar vegetable crops including Chinese cabbage (Brassica pekinensis rupr., cv. Lu-Bai 3), autumn greens (B. chinensis L., cv. Piao-Geng-Bai), winter greens (B. var. rosularis Tsen et Lee, cv. You-Dong-Er), and summer greens (B. chinensis L., cv. Zao-Shu 5), respectively. Each experiment included one CK treatment without K, N and P fertilizers applied, and four treatments with from low to high doses, 0-300 kg hm-2 for Chinese cabbage, 0-150 kg hm-2 for autumn and winter greens and 0-180 kg hm-2 for summer greens, of K fertilizers in the form of sulfate of potash (SOP) applied together with N and P fertilizers. One treatment of K fertilizer in the form of muriate of potash (MOP) applied at high levels (150 or 180 kg hm-2) together with N and P fertilizers was included in the experiments of autumn, winter and summer greens , respectively, in order to compare the effects of SOP and MOP. The market yields of the tested crops increased significantly with the increasing rate of K application. The crops supplied with K fertilizers yielded more stably as the CV% of their yields decreased with the rate of K application. K fertilization increased not only K contents but also the amounts of N, P and K absorbed in shoots of autumn, winter and summer greens, which were statistically significantly correlated to their yields. It can also be found that potassium improved the quality of the foliar vegetable crops as their dry mater contents were generally increased and Vc contents obviously increased and nitrate contents markedly decreased. As compared to MOP, SOP was more effective on the yields and quality of autumn, winter and summer greens at the high levels of fertilization.

关键词： foliar vegetable crops nitrate potassium fertilization quality yield

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Simulation of an Inductive Weld Pool Support for Deep Penetration Laser Beam Welding of Metal Parts

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Journal of Iron and Steel research International 2012年第S1期19卷 114-117页

作者： BACHMANN Marcel AVILOV Vjaceslav GUMENYUK Andrey rETHMEIEr michael BAM Federal Institute for Materials research and Testing Unter den Eichen 87Berlin 12205Germany

A three-dimensional laminar steady state numerical model was used to investigate the influence of an alternating current(ac)magnetic field during single pass high power laser beam keyhole welding of 20 mm thick *** three-dimensional heat transfer,fluid dynamics and electromagnetic field equations were solved with the commercial finite element package COMSOL *** physical effects of the process were taken into account:Thermo-capillary(Marangoni)convection at the upper and lower weld pool surfaces,natural convection due to the gravity influence and the latent heat of solid-liquid phase *** were conducted for several magnetic field strengths and it was found that the gravity drop-out associated with welding of thick plates due to the hydrostatic pressure can be prevented by the application of an ac magnetic field below the weld specimen of around 70 mT(rms)at an oscillation frequency of 450 *** inductive support system allows for single-pass laser beam welding of thick aluminum *** flow pattern in the molten zone and the temperature distributions are significantly changed by the application of the electromagnetic forces in the weld pool.

关键词： electromagnetic weld pool support laser beam welding Lorentz force Marangoni stresses natural convection

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