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Sperm limitation affects sex allocation in a parasitoid wasp Nasonia vitripennis

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Insect Science 2019年第5期26卷 853-862页

作者： marlene Chirault Christophe Bressac marlene Goubault Charlotte Lecureuil Institut de Recherche sur la Biologie de I'lnsecte UMR 7261 CNRS - Universite de ToursFaculte des Sciences et TechniquesParc GrandmontToursFrance

Insect reproduction is influenced by various external factors including temperature, a well-studied constraint. We investigated to what extent different levels of sperm limitation of males exposed to different heat stresses (34 and 36℃) afFect fem ales' offspring production and sex allocation in Nasonia vitripennis. In this haplodiploid parasitoid wasp attacking different species of pest flies, we investigated the effect of the quantity of sperm females received and stored in their spermatheca on their sperm use decisions, hence sex allocation, over successive ovipositions. In particular, we compared the sex allocation of females presenting three levels of sperm limitation (i.e.,mated with control, 34 ℃ heat-stressed or 36℃heat-stressed males) on each host they parasitized. To disentangle the potential reduction of sperm quality after a heat stress exposure from that of sperm quantity, we also explored the clutch size and sex ratio produced by fem ales that were partially sperm limited after copulating with multiply mated males. Independently of their sperm numbers, all types of fem ales produced a similar total number of offspring, but the more limited ones had fewer daughters. Sperm limitation further affected the distribution of daughters' production across *** addition to constraints acting on female physiology, male fertility should therefore be considered in studies measuring reproductive outputs of insects submitted to heat stresses.

关键词： heat stress multiple mating offspring production dynamic sex ratio sperm stock sperm use

Do males choose their mates in the lekking moth Achroia grisella？ Influence of female body mass and male reproductive status on male mate choice

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Insect Science 2018年第5期25卷 861-868页

作者： marlene Goubault Rebecca Burlaud Institut de Recherche sur la Biologie de I'Insecte UMR 7261 CNRS-Universite Francois-Rabelais Tours France

Lekking males aggregate to attract females and contribute solely to egg fer- tilization, without any further parental care. Evolutionary theory therefore predicts them to be nonchoosy toward their mates, because any lost mating opportunities would out- weigh the benefits associated with such preferences. Nevertheless, due to time costs, the production of energetically costly sexual displays, and potential sperm limitation, the mat- ing effort of lekking males is often considerable. These factors, combined with the fact that many females of varying quality are likely to visit leks, could favor the evolution of male mate preferences. Here, we show that males of the lekking lesser wax moth, Achroia grisella, were indeed more likely to mate with heavier females in choice experiments, even at their virgin mating （i.e., when their reproductive resources have not yet been depleted by previous matings）. This differential female mating success could not be attributed to female behavior as heavy and light females showed similar motivation to mate （i.e., la- tency to approach the males） and time to copulate. Males seem to benefit from mating with heavier females, as fecundity positively correlated with female mass. This new em- pirical evidence shows that male mate choice may have been tmderestimated in lekking species

关键词： fecundity lek lesser wax moth mate choice mating status sexual behavior

NH_3 Plasma Surface Treatments of Engineering Fluoropolymers: A Way to Enhance Adhesion of Ni or Cu Thin Films Deposited by Electroless Plating

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材料热处理学报 2004年第05B期25卷 1092-1097页

作者： Maurice Romand marlene Charbonnier Yves Goepfert Laboratoire de Sciences et Ingenierie des Surfaces and Laboratoire de Sciences et Ingenierie des Surfaces andUMR 5180 des Sciences Analytiques Universite Claude Bernard - Lyon 1 69622 Villeurbanne Cedex France

This paper describes the electroless Ni or Cu plating of some fiuoropolymer substrates through a tin-free activation process. Materials subjected to surface metallization are commercial Teflon() FEP, Nafion(), ACLAR() and LaRCTM-CP1 thin films which have recently gained a large scientific and technological interest due to their excellent thermal, chemical, mechanical and dielectric properties. The original approach implemented in the present work involves: (i)the grafting of nitrogen-containing functionalities on the polymer surfaces through plasma treatments in ammonia, (ii) the direct catalysis of the so-modified surfaces via their immersion in a simple acidic PdCl2 solution (i.e. without using a prior surface sensitization in an acidic SnCl2 solution), and finally (iii) the electroless metallization itself. However, prior to the immersion in the industrial plating baths, the chemical reduction of the Pd+2 species (species covalently tethered on the nitrogen-containing groups) to metallic palladium (PdO) is shown to be a key factor in catalyzing the electroless deposition initiation. This is made by immersion in an hypophosphite (H2PO2-) solution. Wettability measurements and X-ray photoelectron spectroscopy (XPS) experiments are used to characterize every surface modification step of the developed process. A cross-hatch tape test was used to asses the adhesion strength of the electroless films that is shown qualitatively good. In addition, a fragmentation test was developed in combination with electrical measurements. Its use allows to distinguish different adhesion levels at the metal/polymer interface and to evidence the influence of some processing parameters.

关键词：镍化学镀层铜化学镀层等离子表面处理表面催化 XPS 剥离试验

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Marking RNA:m^6A writers,readers,and functions in Arabidopsis

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Journal of Molecular Cell Biology 2019年第10期11卷 899-910页

作者： marlene Reichel Tino Koster Dorothee Staiger RNA Biology and Molecular Physiology Faculty of BiologyBielefeld University33615 BielefeldGermany

N^6-methyladenosine(m^6A)emerges as an important modification in eukaryotic mRNAs.m^6A has first been reported in 1974,and its functional significance in mammalian gene regulation and importance for proper development have been well *** arsenal of writer,eraser,and reader proteins accomplish deposition,removal,and interpretation of the m^6A mark,resulting in dynamic *** led to the concept of an epitranscriptome,the compendium of RNA species with chemical modification ofthe nucleobases in the cell,in analogy to the *** m^6A has long been known to also exist in plant mRNAs,proteins involved in m^6A metabolism have only recently been detected by mutant analysis,homology search,and mRNA interactome capture in the reference plant Arabidopsis *** ofthe m^6A modification causes severe developmental abnormalities of leaves and roots and altered timing of reproductive ***,m^6A modification affects viral ***,we discuss recent progress in identifying m^6A sites transcriptome-wide,in identifying the molecular players involved in writing,removing,and reading the mark,and in assigning functions to this RNA modification in *** highlight similarities and differences to m^6A modification in mammals and provide an outlook on important questions that remain to be addressed.

关键词： Arabidopsis m^6A mRNA interactome posttranscriptional RNA-binding protein

Effects of a municipal effluent on the freshwater mussel Elliptio complanata following challenge with Vibrio anguillarum

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Journal of Environmental Sciences 2015年第11期27卷 91-99页

作者： Gagne Francois Douville Melanie Fortier marlene Fournier Michel Aquatic Contaminants Research Division Water Science and Technology INRS-Institut Armand-Frappier

The purpose of this study was to examine the cumulative effects of exposure to a pathogenic bacteria and municipal effluent in the freshwater mussel Elliptio complanata. Mussels were exposed to increasing concentrations of an ozone-treated effluent at 15°C for 7 days. A sub-group of mussels was inoculated with Vibrio anguillarum and exposed to the same conditions as *** the exposure period, mussels were collected to assess hemocyte count and viability,immunocompetence（phagocytosis and nitrite production）, oxidative stress/inflammation（cyclooxygenase and lipid peroxidation） and oxygen radical/xenobiotic scavenging activity（metallothioniens, glutathione S-transferase）. The results showed that mussels exposed to municipal effluent had increased hemocyte counts, phagocytosis, nitrites, lipid peroxidation and metallothioneins. In the inoculated mussels, the same responses were observed, in addition to cyclooxygenase and glutathione S-transferase activities. Multivariate analyses revealed that（1）the response pattern changed with effluent concentration, where increased responses observed at low effluent concentrations（〉10%, V/V） were attenuated at higher effluent concentrations,（2）the effluent produced more pronounced changes in lipid peroxidation, metallothionein and hemocyte viability, and（3） the simultaneous presence of V. anguillarum led to more important changes in hemocyte count and viability and nitrite levels. In conclusion, the presence of *** could alter the response of mussels to municipal effluent, which could lead to increased inflammation in mussels.

关键词： Elliptio complanata Immunocompetence Oxidative stress Inflammation Vibrio anguillarum

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Electroactivity of the magnetotactic bacteria Magnetospirillum magneticum AMB-1 and Magnetospirillum gryphiswaldense MSR-1

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 103-110页

作者： Mathias Fessler Qingxian Su marlene Mark Jensen Yifeng Zhang Department of Environmental and Resource Engineering Technical University of DenmarkCopenhagenDK-2800Denmark

Magnetotactic bacteria reside in sediments and stratified water *** are named after their ability to synthesize internal magnetic particles that allow them to align and swim along the Earth’s magnetic field ***,we show that two magnetotactic species,Magnetospirillum magneticum strain AMB-1 and Magnetospirillum gryphiswaldense strain MSR-1,are *** *** and *** were able to generate current in microbial fuel cells with maximum power densities of 27 and 11μW/m^(2),*** the presence of the electron shuttle resazurin both species were able to reduce the crystalline iron oxide hematite(Fe_(2)O_(3)).In addition,*** could reduce poorly crystalline iron oxide(FeOOH).Our study adds *** and *** to the growing list of known electroactive bacteria,and implies that electroactivity might be common for bacteria within the Magnetospirillum genus.

关键词： Magnetotactic bacteria Magnetospirillum magneticum Magnetospirillum gryphiswaldense Extracellular electron transfer Microbial fuel cells

The role of viruses in the pathogenesis of Parkinson’s disease

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Neural Regeneration Research 2021年第6期16卷 1200-1201页

作者： JoséFidel Baizabal-Carvallo marlene Alonso-Juarez Department of Science and Engineering University of GuanajuatoMéxico National Polytechnic Institute México

Parkinson’s disease(PD)is a neurological degenerative disorder characterized by loss of dopaminergic neurons in the substantia nigra(SN)and intracellular inclusions called Lewy bodies and Lewy tangles,composed mainly by aggregates of α-*** et al.(2003)proposed that the olfactory epithelium and intestines are the anatomical sites where PD initiates;as pathological aggregates ofα-synuclein are detected in these tissues in very early or prodromal *** this scenario,α-synuclein seems to reach the central nervous system(CNS)by axonal transport through the sympathetic nervous system,the glossopharyngeal and vagus nerves as well as the olfactory pathways(Braak et al.,2003).

关键词： al. epithelium pathogenesis

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Characterization of Structural Variability of the Allergenic 2S Albumin Ses i 1 Using Combinatorial Proteomics

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Journal of Analysis and Testing 2018年第2期2卷 158-167页

作者： marlene Hummel Tina Wigger Jens Brockmeyer Institute of Food Chemistry University of MuensterCorrensstr.4548149 MünsterGermany Department of Food Chemistry Institute of Biochemistry and Technical BiochemistryUniversity StuttgartAllmandring 5B70569 StuttgartGermany

Allergy to sesame seeds is a food allergy of high relevance due to its high abundance and the potential to elicit allergenic reactions,possibly resulting in *** major sesame allergen Ses i 1 is a 2S albumin belonging to the family of seed storage proteins and despite its high allergenicity,comprehensive knowledge about Ses i 1 variants is still ***,therefore,performed a detailed sequence analysis and characterized the C-and N-terminal ragged clipping of the small and large subunit of Ses i 1 using high-resolution mass spectrometry and the combination of bottom–up,middle–down,and top–down proteomic *** detected extensive clipping at the C-terminus of the large(3–9 aa)and the small subunit(0–7 aa).In addition,the N-terminal conversion from glutamine to pyroglutamate and limited N-terminal clipping was confirmed for both ***,we observed a sequence conflict at position 147 of Ses i 1 as well as a sequence shift of the large subunit compared to the reference sequence of the precursor.

关键词： Allergens High-resolution mass spectrometry Sesame LC–MS Ragged clipping Ses i 1

An integrated suspended sediment transport monitoring and analysis concept

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International Journal of Sediment Research 2014年第2期29卷 135-148页

作者： marlene HAIMANN Marcel LIEDERMANN Petra LALK Helmut HABERSACK Christian Doppler Laboratory for Advanced Methods in River Monitoring Modelling and EngineeringInstitute of Water ManagementHydrology and Hydraulic Engineering Department of WaterAtmosphere and EnvironmentBOKU-University of Natural Resources and Life SciencesVienna

A new integrated suspended sediment monitoring strategy applying direct and indirect technologies is *** sensors continuously record the turbidity at one point in the channel cross section close to the river bank and are calibrated by water samples taken close to the *** measurements are performed to establish the distribution of suspended sediment in a cross section(bottle samples combined with acoustic devices).Using correction factors(probe and cross-sectional factor) these monitoring methods are combined and it is,thus,possible to fully document the temporal and spatial variability of the suspended sediment transport and to estimate the suspended sediment load for certain time *** monitoring strategy was implemented at various measurement sites in Austria as well as at the Hainburg Road Bridge site on the Danube *** has already been successfully applied for three years at this measurement site and suspended sediment loads during high discharges up to a 15 year flood event have been *** evaluate the new monitoring methods the results were compared with load estimation methods found in the literature including averaging and ratio estimators as well as rating *** results prove that with the new methodology,the temporal variability of the suspended sediment transport can be detected more accurately compared with the other *** also demonstrate that the additional consideration of the spatial distribution of the suspended sediment concentration in the cross section is crucial as the mean concentration in the cross section can significantly exceed the concentration near the banks,especially at large rivers like the Danube River.

关键词： Suspended sediment Integrated suspended sediment monitoring programme Turbidity sensor Acoustic devices Load estimates