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Effects of Cadmium on Polar Lipid Composition and Unsaturation in Maize(Zea mays) in Hydroponic Culture

Journal of Integrative Plant Biology 2007年第12期49卷 1693-1702页

作者： Radhouane Chaffai Tinni Nouhou Seybou Brahim Marzouk Ezzedine EI Ferjani Laboratoire de Bio-physiologie Cellulaires Vegetales Faculte des Sciences de Bizerte 7021 Zarzouna-BizerteTunisie Laboratoire ERTAC physiologie et Genetique Vegetales 63177 AubiereClermont FerrandFrance Laboratoire d'Adaptation et d'Amelioration des Plantes Institut National de la Recherche Scientifique et Technique(INRST)BP 95-2050 Hammam-LifTunisie

This study aimed to evaluate the effect of Cd exposure （100 μmol/L） on polar lipid composition, and to examine the level of fatty acid unsaturation in maize （Zea mays L.）. In roots, the level of 16：0 and monounsaturated fatty acids （16：1 ＋ 18：1） decreased in phosphatidylcholine （PC） and phosphatidylethanolamine （PE）. In contrast, the proportion of unsaturated 18-C fatty acid species showed an opposite response to Cd. The content, on the other hand, of PC, PE, digalactosyldiacylglycerol （DGDG）, and steryl lipids increased in roots （2.9-, 1.6-, 5.3-, and 1.7-fold increase, respectively）. These results suggest that a more unsaturated fatty acid composition than found in control plants with a concomitant increase in polar lipids may favor seedling growth during Cd exposure. However, the observed increase in the steryl lipid （SL）： phospholipid （PL） ratio （twofold）, the decrease in monogalactosyldiacylglycerol （MGDG）： DGDG ratio, as well as the induction of lipid peroxidation in roots may represent symptoms of membrane injury. In shoots, the unsaturation level was markedly decreased in PC and phosphatidylglycerol （PG） after Cd exposure, but showed a significant increase in sulfoquinovosyldiacylglycerol （SQDG）, MGDG and DGDG. The content of PG and MGDG was decreased by about 65%, while PC accumulated to higher levels （4.4-fold increase）. Taken together, these changes in the polar lipid unsaturation and composition are likely to be due to alterations in the glycerolipid pathway. These results also support the idea that the increase in overall unsaturation plays some role in enabling the plant to withstand the metal exposure.

关键词： cadmium fatty acids heavy metal stress lipid peroxidation polar lipids unsaturation level Zea mays.

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Production and characterization of bioaerosols for model validation in spacecraft environment

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Journal of Environmental Sciences 2018年第7期30卷 227-238页

作者： Anniina Salmela Eero Kokkonen Ilpo Kulmala Anna-Maria Veijalainen Rob van Houdt Natalie Leys Audrey Berthier Ilyin Viacheslav Sergey Kharin Julia Morozova Alexander Tikhomirov Pertti Pasanen department of Environmental and Biological Sciences University of Eastern Finland PO Box 1627 FI-70211 Kuopio Finland VTT Ltd PO Box 1300 FI-33100 Tampere Finland Microbiology Unit Belgian Nuclear Research Centre B-2400 Mol Belgium institut de medecine et de physiologie spatiales BP 74404 F-31405 Toulouse Cedex France institute of Bio-Medical Problems 76-A Khorosheu Skoye shosse RU-123007 Moscow Russia institute of Biophysics SB RAS Akademgorodok Krasnoyarsk RU-660036 Russia

This study aimed to evaluate the suitability of two bioaerosol generation systems（dry and wet generation） for the aerosolization of microorganisms isolated from the International Space Station, and to calibrate the produced bioaerosols to fulfill the requirements of computational fluid dynamics model（CFD） validation. Concentration, stability, size distribution, agglomeration of generated bioaerosol and deposition of bioaerosols were analyzed. In addition, the dispersion of non-viable particles in the air was *** proved that wet generation from microbial suspensions could be used for the production of well-calibrated and stabile bioaerosols for model validation. For the simulation of the natural release of fungal spores, a dry generation method should be used. This study showed that the used CFD model simulated the spread of non-viable particles fairly well. The mathematical deposition model by Lai and Nazaroff could be used to estimate the deposition velocities of bioaerosols on surfaces, although it somewhat underestimated the measured deposition velocities.

关键词： Bioaerosol Modeling CFD Spacecraft Fungi Bacteria

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Arabidopsis NRTI.1 Is a Bidirectional Transporter Involved in Root-to-Shoot Nitrate Translocation

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Molecular Plant 2013年第6期6卷 1984-1987页

作者： Sophie Léran Stéphane Muños Chantal Brachet Pascal Tillard Alain Gojon Benoît Lacombe Laboratoire de Biochimie et physiologie Moléculaire des Plantes Institut de Biologie Intégrative des Plantes ‘Claude Grignon’ UMR CNRS/INRA/SupAgro/UM2 Place Viala 34060 Montpellier cedex France

dear Editor, In most plants, nitrogen （N） is acquired by roots in the form of nitrate （NO3-）. In many species, NO3- is not assimi- lated in the roots, but is secreted into the xylem sap for translocation to the shoot, where it enters the cells to be metabolized and/or stored in the vacuoles. Several plasma membrane transporters involved in NO3- influx into the cell have been identified in Arabidopsis （Wang et ai., 2012）, especially in the roots where members of the NPF （NRTI/PTR Family, L^ran et al., 2013） and NRT2 transporter families are predominantiy implicated. Concerning efflux to the xylem sap, only one transporter, NPF7.3/NRT1.5, has been shown to be involved. However, physiological characterization of npf7.31nrtl.5 knockout mutant plants demonstrated that other transporter（s） is （are） also contributing to xylem Ioad- inq of NO^- （Lin et al., 2008）.

关键词： NRT1.1 Bidirectional Transporter Nitrate

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Facilitated Fe Nutrition by Phenolic Compounds Excreted by the Arabidopsis ABCG37/PDR9 Transporter Requires the IRT1/FRO2 High-Affinity Root Fe^2＋ Transport System

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Molecular Plant 2016年第3期9卷 485-488页

作者： Pierre Fourcroy Nicolas Tissot Frederic Gaymard Jean-Francois Briat Christian Dubos Biochimie et physiologie Moldculaire des Plantes Centre National de la Recherche Scientifique Institut National de la Recherche Agronomique Universite Montpellier SupAgro Bat 7 2 place Viala 34060 Montpellier Cedex 1 France

Iron （Fe） is an essential metal nutrient for plant productivity and plant product quality （Briat et al., 2015）. Fe exists under two forms, ferrous （Fe^2＋） or ferric （Fe^3＋）, and is very reactive with oxygen, explaining why Fe plant nutrition is dependent upon both Fe chelation and Fe reduction. Fe availability in the soil is pH dependent, this metal being particularly insoluble in its ferric form in calcareous soils, representing one-third of the world＇s cultivated soils. Consequently, plants grown on these soils, in particular non-graminaceous plants, often suffer from Fe deficiency, which alters their growth.

关键词： explaining dependent calcareous

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A SEM-based method to determine the mineralogical composition and the particle size distribution of suspended sediment

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International Journal of Sediment Research 2019年第2期34卷 85-94页

作者： Sylvain Pinet Bruno Lartiges Jean-Michel Martinez Sylvain Ouillonc University of Toulouse (Paul Sabatier) Geosciences Environment ToulouseCNRS(Centre National de la Recherche Scientifique)IRD(Institut de Recherche pour le Développement) instituto de Geosciencias Universidade de BrasiliaCampus Universitario Darcy RibeiroICC Centro University of Toulouse LEGOS(Laboratoire d'Etudes en Géophysique et Océanographie Spatiales)

A robust method for characterizing the mineralogy of suspended sediment in continental rivers is *** encompasses 3 steps:the filtration of a few milliliters of water,measurements of X-ray energy dispersive spectra using Scanning Electron Microscopy(SEM),and robust machine learning tools of *** method is applied to suspended particles collected from various Amazonian rivers.A total of more than 204,000 particles were analyzed by SEM-EDXS(Energy Dispersive X-ray Spectroscopy),*** 15,700 particles per sampling station,which lead to the identification of 15 distinct groups of mineralogical *** size distribution of particles collected on the filters was derived from the SEM micrographs taken in the backscattered electron imaging mode and analyzed with ImageJ *** determination of the main mineralogical groups composing the bulk sediment associated with physical parameters such as particle size distribution or aspect ratio allows a precise characterization of the load of the terrigenous particles in rivers or *** the case of the Amazonian rivers investigated,the results show that the identified mineralogies are consistent with previous studies as well as between the different samples *** method enabled the evolution of grain size distribution from fine to coarse material to be described in the water *** about hydrodynamic sorting of mineral particles in the water column are also briefly *** proposed method appears well suited for intensive routine monitoring of suspended sediment in river systems.

关键词： Mineralogy Scanning Electron Microscopy Suspended sediment Machine learning Particle size distribution

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Perturbed initial orbit determination

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Astrodynamics 2024年第3期8卷 401-416页

作者： Alberto Fossà Matteo Losacco Roberto Armellin institut Supérieur de l’Aéronautique et de l’Espace Toulouse31400France Te PūnahaĀtea-Space institute The University of AucklandAuckland1010New Zealand

An algorithm for robust initial orbit determination (IOD) under perturbed orbital dynamics is presented. By leveraging map inversion techniques defined in the algebra of Taylor polynomials, this tool returns a highly accurate solution to the IOD problem and estimates a range centered on the aforementioned solution in which the true orbit should lie. To meet the specified accuracy requirements, automatic domain splitting is used to wrap the IOD routines and ensure that the local truncation error, introduced by a polynomial representation of the state estimate, remains below a predefined threshold. The algorithm is presented for three types of ground-based sensors, namely range radars, Doppler-only radars, and optical telescopes, by considering their different constraints in terms of available measurements and sensor noise. Finally, the improvement in performance with respect to a Keplerian-based IOD solution is demonstrated using large-scale numerical simulations over a subset of tracked objects in low Earth orbit.

关键词： initial orbit determination(IOD) range radar Doppler radar optical telescope differential algebra(DA)

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NOTES SUR LE PHOTOSTAde de QUELQUES VARIetES de RIZ AU VIet-NAM deMOCRATIQUE

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植物生理学报 1959年第3期 11-22页

作者： BUI HUY DAP NGHIEM PHU CHUAN Directeur de l'institut d'Agriculture et de Sylviculture de Hanoi Chef du Laboratoire de physiologie végétale

En raison du climat tropical du pays,au Viet-Nam on peut faire plusieurs campagnes de riz paran,dont les principales sont les suivantes pour la région du Nord:—Campagne du cinquième mois,avec semis en Novembre,Déc... 详细信息

关键词： der FL 植物生理学 NOTES SUR LE PHOTOSTAde de QUELQUES VARIetES de RIZ AU VIet-NAM deMOCRATIQUE IV de NAM

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Nitrate Transport, Sensing, and Responses in Plants

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Molecular Plant 2016年第6期9卷 837-856页

作者： Jose A. O'Brien Andrea Vega Eleonore Bouguyon Gabriel Krouk Alain Gojon Gloria Coruzzi Rodrigo A. Gutierrez departamento de Genetica Molecular y Microbiologia FONDAP Center for Genome Regulation Millennium Nucleus Center for Plant Systems and Synthetic Biology Pontificia Universidad Cat61ica de Chile 8331150 Chile departamento de Fruticultura y Enologia Pontificia Universidad Catolica de Chile Santiago 7820436 Chile departamento de Ciencias Vegetales Pontificia Universidad Catolica de Chile Santiago 7820436 Chile department of Biology Center for Genomics and Systems Biology New York University New York NY 10003 USA SLaboratoire de Biochimie et physiologie Moleculaire des Plantes Institut de Biologie Integrative des Plantes 'Claude Grignon' UMR CNRS INRA SupAgro UM 2 Place Viala 34060 Montpellier Cedex France

Nitrogen （N） is an essential macronutrient that affects plant growth and development. N is an important component of chlorophyll, amino acids, nucleic acids, and secondary metabolites. Nitrate is one of the most abundant N sources in the soil. Because nitrate and other N nutrients are often limiting, plants have developed sophisticated mechanisms to ensure adequate supply of nutrients in a variable environment. Nitrate is absorbed in the root and mobilized to other organs by nitrate transporters. Nitrate sensing activates signaling pathways that impinge upon molecular, metabolic, physiological, and developmental responses locally and at the whole plant level. With the advent of genomics technologies and genetic tools, important advances in our understanding of nitrate and other N nutrient responses have been achieved in the past decade. Furthermore, techniques that take advantage of natural polymor- phisms present in divergent individuals from a single species have been essential in uncovering new components. However, there are still gaps in our understanding of how nitrate signaling affects biolog- ical processes in plants. Moreover, we still lack an integrated view of how all the regulatory factors iden- tified interact or crosstalk to orchestrate the myriad N responses plants typically exhibit. In this review, we provide an updated overview of mechanisms by which nitrate is sensed and transported throughout the plant. We discuss signaling components and how nitrate sensing crosstalks with hormonal pathways for developmental responses locally and globally in the plant. Understanding how nitrate impacts on plant metabolism, physiology, and growth and development in plants is key to improving crops for sustainable agriculture.

关键词： nitrate nitrate transporters hormones N-foraging

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Gαq,Gγ1 and Plc21C Control Drosophila Body Fat Storage

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Journal of Genetics and Genomics 2014年第5期41卷 283-292页

作者： Jens Baumbach Yanjun Xu Philip Hehlert Ronald P.Khnlein Abteilung Molekulare Entwicklungsbiologie Forschungsgruppe Molekulare Physiologie Max-Planck-Institut fr biophysikalische Chemie Abteilung Molekulare Entwicklungsbiologie Forschungsgruppe Molekulare PhysiologieMax-Planck-Institut fr biophysikalische Chemie

mobilization of body fat is essential for energy homeostasis in animals. In insects, the adipokinetic hormone （Akh） systemically controls body fat mobilization. Biochemical evidence supports that Akh signals via a G protein-coupled receptor （GPCR） called Akh receptor （AkhR） using cyclic-AMP （cAMP） and Ca2＋ second messengers to induce storage lipid release from fat body cells. Recently, we provided genetic evidence that the intracellular calcium （iCa2＋） level in fat storage cells controls adiposity in the fruit fly Drosophila melanogaster. However, little is known about the genes, which mediate Akh signalling downstream of the AkhR to regulate changes in iCa2＋. Here, we used thermogenetics to provide in vivo evidence that the GPCR signal transducers G protein α q subunit （Gαq）, G protein γ1 （Gγ1） and Phospholipase C at 21C （Plc21C） control cellular and organismal fat storage in Drosophila. Transgenic modulation of Gαq, Gγ1 and Plc21C affected the iCa2＋ of fat body cells and the expression profile of the lipid metabolism effector genes midway and brummer, which results in severely obese or lean flies. Moreover, functional impairment of Gαq, Gγ1 and Plc21C antagonised Akh-induced fat depletion. This study characterizes Gαq, Gγ1 and Plc21C as anti-obesity genes and supports the model that Akh employs the Gαq/Gγ1/Plc21C module of iCa2＋ control to regulate lipid mobilization in adult Drosophila.

关键词： Plc21C Gαq Gγ1 Calcium Fat storage Adipokinetic hormone

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ＲＥＧＵＬＡＲＩＴＹＴＨＥＯＲＹＦＯＲＳＹＳＴＥＭＳＯＦＰＡＲＴＩＡＬＤＩＦＦＥＲＥＮＴＩＡＬＥＱＵＡＴＩＯＮＳＷＩＴＨＮＥＵＭＡＮＮＢＯＵＮＤＡＲＹＣＯＮＤＩＴＩＯＮＳ

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Chinese Annals of Mathematics,Series B 2002年第2期23卷 165-180页

作者： A.BENSOUSSAN J.FREHSE UniversityParis Institut fur Angewandte Mathematik Dauphineand CNES(CentreNationald’Etudes Spatiales)2PlaceMauriceQuentin75001Pari

The objective of this paper is to consider the theory of regularity of systems of partial differential equations with Neumann boundary conditions. It complements previous works of the authors for the Dirichlet case. This type of problem is motivated by stochastic differential games. The Neumann case corresponds to stochastic differential equations with reflection on boundary of the domain.

关键词： Regularity theory Neumann boundary conditions Dirichlet problem

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