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Climate change impacts on crop yield,crop water productivity and food security-A review

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Progress in Natural Science:Materials International 2009年第12期19卷 1665-1674页

作者： Shahbaz Khan Division of Water Sciences UNESCOI Rue Miollis 75 732 Paris Cedex 15.SPFrance

This paper provides a comprehensive review of literature related to the assessment of climate change impacts on crop productivity using climate,water and crop yield *** existing studies present that climate change models with higher spatial resolution can be a way forward for future climate ***,stochastic projections of more than one climate model are necessary for providing insights into model uncertainties as well as to develop risk management *** is projected that water availability will increase in some parts of the world,which will have its own effect on water use efficiency and water *** production can increase if irrigated areas are expanded or irrigation is intensified,but these may increase the rate of environmental degradation. Since climate change impacts on soil water balance will lead to changes of soil evaporation and plant transpiration,consequently,the crop growth period may shorten in the future impacting on water *** yields affected by climate change are projected to be different in various areas,in some areas crop yields will increase,and for other areas it will decrease depending on the latitude of the area and irrigation *** modelling results show that an increase in precipitation will increase crop yield,and what is more,crop yield is more sensitive to the precipitation than *** water availability is reduced in the future,soils of high water holding capacity will be better to reduce the impact of drought while maintaining crop *** the temperature increasing and precipitation fluctuations,water availability and crop production are likely to decrease in the *** the irrigated areas are expanded,the total crop production will increase;however,food and environmental quality may degrade.

关键词： Climate change impacts Crop yield Food security Water productivity Water use efficiency

SECOND-ORDER CONVERGENCE PROPERTIES OF TRUST-REGION METHODS USING INCOMPLETE CURVATURE INFORMATION, WITH AN APPLICATION TO MULTIGRID OPTIMIZATION

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Journal of Computational Mathematics 2006年第6期24卷 676-692页

作者： Serge Gratton Annick Sartenaer Philippe L. Toint CERFACS av. G. Coriolis Toulouse France Department of Mathematics University of Namur 61 rue de Bruxelles B-5000 Namur Belgium

Convergence properties of trust-region methods for unconstrained nonconvex optimization is considered in the case where information on the objective function＇s local curvature is incomplete, in the sense that it may be restricted to a fixed set of ＂test directions＂ and may not be available at every iteration. It is shown that convergence to local ＂weak＂ minimizers can still be obtained under some additional but algorithmically realistic conditions. These theoretical results are then applied to recursive multigrid trust-region methods, which suggests a new class of algorithms with guaranteed second-order convergence properties.

关键词： Nonlinear optimization Convergence to local minimizers Multilevel problems.

Polyurethanes from Kraft Lignin without Using Isocyanates

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Journal of Renewable Materials 2018年第4期6卷 413-425页

作者： F.J.Santiago-Medina M.C.Basso A.Pizzi L.Delmotte LERMAB University of Lorraine27 rue Philippe Seguin88000 EpinalFrance Department of Physics King Abdulaziz UniversityJeddahSaudi Arabia Material Science Institute of Mulhouse UMR CNRS 7361University of Upper Alsace15 rue Jean StarckyBP 248868057 Mulhouse CedexFrance

The reaction of a desulphurized kraft lignin with hexamethylene diamine and dimethyl carbonate has allowed the development of isocyanate-free polyurethane *** present research work is based on previous studies made with hydrolyzable and condensed tannins,but takes advantage of the higher number of hydroxyl groups present in lignin and their different aliphatic and aromatic *** obtained materials were analyzed by Fourier transform infrared(FTIR)spectroscopy,matrix-assisted laser desorption ionization time-of-flight(MALDI-TOF)mass spectrometry and solid-state cross-polarization/magic angle spinning(CP MAS)13C nuclear magnetic resonance(NMR),which have revealed the presence of urethane *** interpretation of the results has shown a larger number of species than when tannins were used and has indicated the presence of two types of bonds in the new molecules formed:ionic and covalent bonds.

关键词： Lignin urethanes non-isocyanate polyurethanes MALDI-TOF FTIR

Time and Dose-related Effects of the Pyrethroid Fluvalinate on Haemolymph Carbohydrates and Gut Lipids of Honeybees,Following in vivo Injection of very Low Doses

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Biomedical and Environmental Sciences 1993年第2期6卷 145-153页

作者： K.M'DIAYE M.BOUNIAS University University of AvignonBiomathematics & Toxicology23 rue du 58eR.I.F 84000 AvignonFranceof AvignonBiomathematics & Toxicology23 rue du 58eR.I.F 84000 AvignonFrance

The injection to emerging adult workerbees with fluvalinate doses ranging from 1 femtomol to 1 nanomol per individual resulted in a reduction of haemolymph carbohydrate concentrations, particularly at the lowest dose 1 hour after injections. At the same time, a large increase was observed for triacylglycerols and to a much lesser extent for steroids and phospholipids with 0.1 picomol per bee. By contrast, fatty acids, steroids and triacylglycerols exhibited a depress at the higher dose. Most responses were thus biphasic, showing that much attention should be paid to the effects of very low doses of pesticide.

关键词： Time and Dose-related Effects of the Pyrethroid Fluvalinate on Haemolymph Carbohydrates and Gut Lipids of Honeybees,Following in vivo Injection of very Low Doses very

The Multilayer’s Control of ARGONAUTE 1 Contents

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Molecular Plant 2020年第1期13卷 1-3页

作者： Jean Molinier Institut de Biologie Moleculaire des Plantes 12 Rue du General Zimmer67000 StrasbourgFrance

ARGONAUTE proteins(AGO)are key effectors of the RNA silencing pathways involved in the regulation of gene expression and in antiviral defense(Vaucheret,2008).Among the 10 AGO proteins present in Arabidopsis,AG01 is essential for plant development and defense response,participating in both microRNA(miRNA)-and small interfering RNA(siRNA)-mediated gene silencing(Vaucheret,2008).Given that AG01 depletion is lethal,only hypomorphic mutant plants are viable and display a large variety of developmental phenotypes(Vaucheret,2008).Importantly,the fine tuning of AG01 content is an important process orchestrated by several different pathways(Cho et al.,2016).It was recently described that the mode of action of AG01 is not only restricted to the posttranscriptional gene silencing pathway taking place in the ***,several nuclear AG01 functions have been identified(Bajczyk et al.,2019).Thus,the characterization of the different AG01 pools implies that specific subcellular pathways might trigger AGOI turnover and that complex regulatory processes might interplay to specifically fine tune AG01 content.

关键词： viable depletion restricted

De novo *** copy number variations in multiple sclerosis susceptibility

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Cellular & Molecular Immunology 2018年第9期15卷 812-814页

作者： Kalthoum Tizaoui Department of Basic Sciences Medicine Faculty of TunisTunis El Manar University15 Rue Djebel LakdarTunis 1007Tunisia

The Human Genome Project has identi-fied,along with single nucleotide polymorphisms(SNPs),a range of other DNA sequence variations,including insertions and deletions of nucleotides and translocations of various segments of a chromosome.1 These variations have,collectively,been named copy number variants(CNVs).1 They represent a major source of genomic variation,with nearly 1500 variable regions covering approximately 12%of the human genome.2 A CNV could act directly by affecting gene dosage and gene expression through complex *** is thought,therefore,that CNVs in genedosage sensitive genes may have considerable influence on disease susceptibility.2 Among genes overlapped by CNVs,significant enrichments in certain gene ontology categories have been identified,including those related to immune responses and interaction with the environment.3 CNVs have already been associated with several monogenic,syndromic and complex diseases.

关键词： dosage collective number

A new Upper Carboniferous stem-orthopteran （Insecta） from Ningxia （China）

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Insect Science 2012年第2期19卷 153-158页

作者： Olivier Béthoux Jun-Jie Gu Dong Ren College of Life Sciences Capital Normal UniversityBeijingChina 40 rue d'Aveillans 38770 La Motte d'AveillansFrance

During the Upper Carboniferous, orthopteran insects （grasshoppers, katydids, and crickets） were represented by numerous species distantly related to crown-orthopterans, such as lobeattid and cnemidolestodean insects. The panorthopterans, including total- orthopterans and their closest relatives, are represented by comparatively rarer species in localities of this period. Here we describe Heterologus duyiwuer sp. nov., an infrequent panorthopteran from the Late Carboniferous locality of Xiaheyan Village （Zhongwei City, Ningxia Hui Autonomous Region, China）. The only available specimen is composed of an isolated forewing exhibiting a combination of character states previously unknown, in particular the lack of posterior radius （RP） / anterior Media （MA） connection, late branchings of the media （M） and anterior cubitus （CuA）, and a branched posterior branch of the posterior cubitus （CuPb）. Based on its unusual branching pattern, the composite stem resulting from the fusion of CuA and CuPaa （second anterior branch of CuP） is assumed to be composed of a branched CuA and a simple CuPaa.

关键词： Archaeorthoptera homology Namurian stem-orthopterans Tupo Formation

Wavelet filter analysis of splitting and coupling of seismic normal modes below 1.5 mHz with superconducting gravimeter records after the December 26, 2004 Sumatra earthquake

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Science China Earth Sciences 2006年第12期49卷 1259-1269页

作者： Jacques Hinderer Institut de Physique du Globe de Strasbourg (UMR 7516 CNRS-ULP) 5 rue Descartes 67084 Strasbourg Cedex France

New generation superconducting gravimeters (SGs), which have been demonstrated to be better than the best seismometers STS-1 at frequencies below 1 mHz, can be accepted as the quietest vertical seismometers for observation of long-period earth free oscillations. Wavelet filtering with narrow band-pass frequency response as shown in this paper is very helpful in removing at- mospheric pressure effects from on gravity records in long-period seismic mode frequency bands. The processing of high quality SG records after the great Sumatra earthquake (Dec. 26, 2004) with wavelet filtering leads to clear observations of all coupled toroidal modes below 1.5 mHz except these for 0T5, 0T7 and 1T1; moreover 1T2 and 1T3 are, for the first time, unambiguously revealed in the vertical components of the free oscillations. The three well-resolved splitting singlets of overtones 2S1 are observed from a single SG record for the first time.

关键词： superconducting gravimeter,Sumatra earthquake,wavelet filter,Earth free oscillations,pressure correction.

EXISTENCE AND UNIQUENESS OF A SOLUTION TO AN AEROACOUSTIC MODEL

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Chinese Annals of Mathematics,Series B 2002年第1期23卷 11-24页

作者： PH. DESTUYNDER,E. GOUT D’HENIN Cnam-Dpartment de Mathmatiques/IAT Chaire de Calcul Scientifique, 292, rue Saint-Martin 75003, Paris, France. Cnam-Dṕartment de Mathḿatiques/IAT Chaire de Calcul Scientifique 292 rue Saint-Martin 75003 Paris France

A linear modelling of aeroacoustic waves propagation is discussed. The first point is an existence and uniqueness, theorem. But restrictive assumptions are required on the velocity of the flow. Then a counter example ... 详细信息

关键词： Fluid-structure Stability Wave propagation Localization of energy Numerical scheme.