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Senescence-specific Alteration of Hydrogen Peroxide Levels in Arabidopsis thaliana and Oilseed Rape Spring Variety Brassica napus ***

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Journal of Integrative Plant Biology 2012年第8期54卷 540-554页

作者： Stefan Bieker lena riester Mark Stahl Jürgen Franzaring Ulrike Zentgraf ZMBP (Center for Plant Molecular Biology) University of TübingenAuf der Morgenstelle 2872076 Tübingen Germany Institute for Landscape and Plant Ecology kologiezentrum 2August-von-Hartmann-Str.370599 StuttgartGermany

In order to analyze the signaling function of hydrogen peroxide （H202） production in senescence in more detail, we manipulated intracellular H202 levels in Arabidopsis thaliala （L.） Heynh by using the hydrogen- peroxide-sensitive part of the Escherichia coil transcription regulator OxyR, which was directed to the cytoplasm as well as into the peroxisomes. H202 levels were lowered and senescence was delayed in both transgenic lines, but OxyR was found to be more effective in the cytoplasm. To transfer this knowledge to crop plants, we analyzed oilseed rape plants Brassica napus L. cv. Mozart for H20~ and its scavenging enzymes catalase （CAT） and ascorbate peroxidase （APX） during leaf and plant development. H202 levels were found to increase during bolting and flowering time, but no increase could be observed in the very late stages of senescence. With increasing H202 levels, CAT and APX activities declined, so it is likely that similar mechanisms are used in oilseed rape and Arabidopsis to control H202 levels. Under elevated CO2 conditions, oilseed rape senescence was accelerated and coincided with an earlier increase in H202 levels, indicating that H202 may be one of the signals to inducing senescence in a broader range of Brassicaceae.

关键词： Arabidopsis thaliana Brassica napus E. coil Oxy-RD intracellular hydrogen peroxide senescence phenotype catalase ascorbatePeroxidase elevated CO2.

Gottfried Konecny:the influence in the global development of the three geosciences

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Geo-Spatial Information Science 2021年第1期24卷 22-26,I0005页

作者： lena Halounová Department of Geomatics Faculty of Civil EngineeringCzech Technical University(CTU)PragueGzech Republic

The paper contains a brief overview of the professional activities of Professor Gottfried Konecny,Professor Emeritus at the Institute of Photogrammetry and GeoInformation,Leibniz University Hannover,Germany,and his influence on photogrammetry,remote sensing and geospatial information science during his time at the University of New Brunswick,Canada,and at the Leibniz *** work can be divided into educational,scientific,application,organizational,and work in international *** activities comprised of giving courses in various languages,consultancy activities,and various other cooperations which took place in many South American countries,in Africa and Asia,for organizations such as the World Bank,United Nations,German Space Agency DLR,to name only a *** in connection with international societies mainly took place during ***’s engagement in the Council of the International Society for Photogrammetry(ISP),renamed the International Society for Photogrammetry and Remote Sensing(ISPRS),and the European Association of Remote Sensing Laboratories(EARSeL)*** was a key figure in bringing many countries and organizations to ISPRS as Ordinary and Sustaining *** Konecny has always been aware of the importance of international cooperation at various levels,also with sister societies such as the International Cartographic Association and the United Nations-Global Geospatial Information Management(UN-GGIM).His application activities span from the photogrammetry-oriented projects he was awarded in Canada,to remote sensing topics and geospatial sciences,combined with cartography during his Hannover *** vision and endless effort are exemplary for a person who has always been devoted to the three geosciences mentioned *** Konecny is the author of a number of books,journal papers and papers presented at international and national *** has been a recognized keynote speaker at many conferences t

关键词： Photogrammetry remote sensing spatial information sciences International Society for Photogrammetry and Remote Sensing research publication project cooperation

Paleoproterozoic,High-Metamorphic,Metasedimentary Units of Siberian Craton

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Acta Geologica Sinica(English Edition) 2009年第5期83卷 875-883页

作者： lena URMANTSEVA Olga TURKINA Institute of Geology and Mineralogy Siberian BranchRussian Academy of SciencesNovosibirskRussia

Sensitive, high-resolution ion microprobe zircon U-Pb ages of Paleoproterozoic, high-grade, metasedimentary rocks from the south-western part of the Siberian Craton are reported. Early Precambrian, high-grade complexes, including garnet-biotite, hypersthene-biotite, and cordierite- bearing gneisses compose the Irkut terrane of the Sharyzhalgay Uplift. Protoliths of studied gneisses correspond to terrigenous sediments, ranging from greywacke to shale. The paragneiss model Nd ages of 2.4-3.1 Ga indicate Archean-to-Paleoproterozoic source provinces. Zircons from gneisses show corerim textures in cathodoluminescence （CL） image. Round or irregular shaped cores indicate detrital origin. Structureless rims with low Th/U are metamorphic in origin. The three age groups of detrital cores are：〉2.7, -2.3, and 1.95-2 Ga. The ages of metamorphic rims range from 1.86 to 1.85 Ga; therefore, the sediments were deposited between 1.95 and 1.86 Ga and derived from Archean and Paleoproterozoic source rocks. It should be noted that Paleoproterozoic metasedimentary rocks of the Irkut Block are not unique. High-grade metaterrigenous sediments, with model Nd ages ranging from 2.3 to 2.5 Ga, are widely distributed within the Aldan and Anabar Shields of the Siberian Craton. The same situation is observed in the North China Craton, where metasedimentary rocks contain detrital igneous zircon grains with ages ranging from 3 to 2.1 Ga （Wan et al., 2006）. All of these sedimentary units were subjected to Late Paleoproterozoic metamorphism. In the Siberian Craton, the Paleoproterozoic sedimentary deposits are possibly marked passive margins of the Early Precambrian crustal blocks, and their high-grade metamorphism was related to the consolidation of the Siberian Craton.

关键词： zircon sensitive high-resolution ion microprobe U-Pb dating metasedimentary rocks,Paleoproterozoic Siberian Craton

Self-assembly of peptide-based nanostructures： Synthesis and biological activity

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Nano Research 2018年第5期11卷 2315-2335页

作者： lena Guyon Elise Lepeltier Catherine Passirani Micro & Nanomedecines Translationnelles-MINT UNIV Angers INSERM U 1066 CNRS UMR 6021 UBL Universite Bretagne Loire Angers F-49933 France

Peptide-based nanostructures have received much attention in the field of drug targeting. In fact, peptides have many advantages such as simplicity of the structure, biocompatibility, and chemical diversity. Moreover, some peptides, which are called cell-penetrating peptides, can cross cellular membranes and carry small molecules, small interfering RNA, or viruses inside live cells. These molecules are often covalently or noncovalently linked to cargoes, thus forming amphiphilic conjugates that can self-assemble. Supramolecular nanostructures formed from peptides are used in nanomedicine as a carrier to protect a drug and to target cancer cells. This review explores aliphatic-chain-conjugated peptides and drug-conjugated peptides that can self-assemble. Special emphasis is placed on the synthesis procedure, nanostructure formation, and biological activity.

关键词： self-assembly cell penetrating peptide nanoparticle peptide

Joint effects of acetochlor and urea on germinating characteristics of crop seeds

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Science China(Life Sciences) 2005年第z1期48卷 1-6页

作者： lena Q. Ma Soil and Water Science Department University of Florida Gainesville FL USA

In order to evaluate ecological risk of agrochemicals in common use, joint toxic effects of acetochlor and urea on germinating characteristics of Chinese cabbage (Brassica Pe-kinensis Rupr) seeds were investigated using the water-culture method and the soil-culture method. The results indicated(that excessive application of acetochlor and urea, when the concentrations were higher than 31.3 mg · kg-1 for acetochlor and 500 mg · kg-1 for urea, had strong inhibitory effects on the rate of seed germination, root elongation and hypocotyl length of Chinese cabbage. The inhibitory rate of the germinating characteristics of Chinese cabbage seeds was significantly increased with an increase in the concentration of acetochlor or urea. The two agrochemicals in water had a stronger toxicity than these in the soil at the same concentration. Among the three indexes, hypocotyl length was the most sensitive to the toxicity of acetochlor and urea.

关键词： ecotoxicology, joint effect, acetochlor, urea, agricultural ecosystem.

Novel intelligent devices: Two-dimensional materials based memristors

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Frontiers of physics 2022年第2期17卷 83-85页

作者： lena Du Zhongchang Wang Guozhong Zhao Department of Physics Capital Normal UniversityBeijing 100048China International Iberian Nanotechnology Laboratory(INL)Avenida Mestre JoséVeiga s/n Braga 4715-330Portugal

Two-dimensional(2D)materials with atomic thickness,non-volatile resistive switching feature and compatibility with the semiconducting technology are naturally a good media of memristors.2D materials-based memristors with excellent performance,low-power consumption and high integration density can be integrated with other circuit components to implement the complicate logic computing,which will become a key driving force for the development of artificial intelligence.

关键词： artificial memristor driving

Phenotype manipulation influences microhabitat choice in pygmy grasshoppers

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Current Zoology 2012年第3期58卷 392-400页

作者： lena WENNERSTEN Einat KARPESTAM Anders FORSMAN School of Natural Sciences Linnaeus University SE-391 82 Kalmar Sweden

The matching habitat choice hypothesis posits that individuals actively choose those microhabitats that best match their specific phenotype to maximize fitness. Despite the profound implications, matching habitat choice has not been unequivo- cally demonstrated. We conducted two experiments to examine the impact of pigmentation pattern in the color polymorphic pygmy grasshopper Tetrix subulata on habitat choice in a laboratory thermal mosaic arena. We found no behavioral differences in the thermal mosaic among pygmy grasshoppers belonging to either pale, intermediate or dark natural color morphs. However, af- ter manipulating the grasshoppers＇ phenotype, the utilization through time of warmer and colder parts of the arena was different for black-painted and white-painted individuals. White-painted individuals used warmer parts of the arena, at least during the ini- tial stage of the experiment. We conclude that microhabitat choice represents a form of behavioural plasticity. Thus, even if the choice itself is flexible and not genetically determined, it can still lead to spatial genetic structure in the population because the phenotypes themselves may be genetically mediated [Current Zoology 58 （3）： 392--400, 2012].

关键词： Behavioral plasticity Color polymorphism Integrated phenotypes Microhabitat use Tetrix Thermoregulation

Tastes of Revolution, Change and Love： Codes of Consumption in Fiction from New China

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2014年第4期8卷 575-597页

作者： lena HENNINGSEN Institute of Chinese Studies University of Freiburg WerthmannstraBe 12 79098 Freiburg Germany

This paper analyses Socialist Realist novels from the early years of the People＇s Republic of China （PRC）, focusing on scenes of food and drink consumption. While these scenes may appear marginal at first glance, the analysis demonstrates how food and its consumption function as codes to normative values. I am therefore proposing a reading of these texts based on the model of intertextuality （Julia Kristeva） and on an anthropological model on （food） consumption （Mary Douglas）, advocating that acts of consumption reveal social hierarchies and the position of the individual therein. These fictional scenes of everyday activities construct fictional characters as heroes or villains. Given the normative value of this officially endorsed literature, these scenes at the same time prescribe （and, likewise, proscribe） certain behavior to their readers. On another level, however, these codes also convey information that could not be openly spelled out at the time, as when the sharing of food is the only way in which two fictional characters can express their love. Simple food can thus be the source of entertainment, enjoyment, suspense, and even nostalgia for contemporary readers, which, in turn, may be one of the reasons for the lasting popularity of the codes described and of a number of the texts presented in the analysis.

关键词： Socialist Realism red classics The Song of Youth food in literature,anthropology of consumption intertextuality

Improving risk reduction potential of weather index insurance by spatially downscaling gridded climate data-a machine learning approach

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Big Earth Data 2023年第4期7卷 937-960页

作者： Sarvarbek Eltazarov Ihtiyor Bobojonov lena Kuhn Thomas Glauben Department of Agricultural Markets Marketing and World Agricultural TradeLeibniz Institute of Agricultural Development in Transition Economies(IAMO)HalleGermany

Open-access gridded climate products have been suggested as a potential source of data for index insurance design and operation in data-limited ***,index insurance requires climate data with long historical records,global geographical coverage and fine spatial resolution at the same time,which is nearly impossible to satisfy,especially with open-access *** this paper,we spatially downscaled gridded climate data(precipitation,temperature,and soil moisture)in coarse spatial resolution with globally available longterm historical records to finer spatial resolution,using satellite-based data and machine learning *** then investigated the effect of index insurance contracts based on downscaled climate data for hedging spring wheat *** study employed countylevel spring wheat yield data between 1982 and 2018 from 56 counties overall in Kazakhstan and *** results showed that in the majority of cases(70%),hedging effectiveness of index insurances increases when climate data is spatially downscaled with a machine learning *** improvements are statistically significant(p≤0.05).Among other climate data,more improvements in hedging effectiveness were observed when the insurance design was based on downscaled temperature and precipitation ***,this study highlights the reasonability and benefits of downscaling climate data for insurance design and operation.

关键词： Climate risk management risk reduction extreme weather random forest ESA parametric insurance