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Mechanical Behaviour and Structure Instability of Al_3Ti Alloy

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Journal of Materials Science & Technology 1994年第1期10卷 1-14页

作者： D.G.Morris(Institute of Structural Metallurgy, university of neuchatel, Avenue de Bellevaux 51, neuchatel, Switzerland) univ of neuchatel Neuchatel Switzerland

Trialuminide alloys of elements such as Ti. Nb or Zr are of particular interest as materials for high temperature usage because their density is very low and specific strength and elastic rnoduli are then very high. This report concentrates on recent work on Al3Ti alloys which have been alloyed with ternary elements such that the higher symmetry ordered cubic structure is obtained, leading to somewhat easier operation of deformation mechan isms and hence improved ductility and *** details of the crystal structure of cubic trialuminides are considered here and it is shown that the materials generally possess some remnant tetragonal chemical ordering which can affect their me chanical behaviour. In addition the compositional range over which a stable single phase is retained is shown to be extremely small, such that in most cases the materials examined show some form of microstructural instability. These instabilities affect the mechanical behaviour of the materials, for exarnple producing general strengthening. leading to precipitation hardening du ring hig h temperature testing, and causing age hardening instabilities during high temperature static or dynamic *** structural instabifity feads to significant modifications at superdislocations, affecting both the dislocation cores and their associated APB's. Failure for these cubic materials still occurs at very small plastic strains and seems to be determined by difficulties of superdislocation creation near a propagating crack rather than by problems of suitable dislocation configuration and mobility. Possible ways to enhance ductility and toughness by alloying and microstructural modification will be discussed.

关键词： Ti Figure Mechanical Behaviour and Structure Instability of Al3Ti Alloy Al

MICROSTRUCTURE AND MECHANICAL PROPERTIES OF Fe_3Al BASED ALLOYS

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Acta Metallurgica Sinica(English Letters) 1995年第Z1期8卷 393-404页

作者： D.G. MORRIS(Institute of Structural Metallurgy, Avenue de Bellevaux 51, university of neuchatel, 2000 neuchatel, SWITZERLAND) univ of neuchatel Switzerland

The promise for industrial applications offered by iron aluminides is today restricted by insufficient ductility at room temperature and mediocre strength and creep resistance at high temperatures. The tendency to embrittlement in the presence of hydrogen or water vapour limits the ductility even more. The atomic arrangements in binary and alloyed variants are examined here and related to the difficulties of dislocation propagation at room and at high temperatures. In this way the influence of intrinsic structure and alloying modifications on mechanical behaviour can be understood. Possibilities for further improving properties through structure control are considered.

关键词： Intermetallics Aluminides Order Anti-phase boundaries Dislocation structures,Anomalous strengthening Solute hardening.

CHLORAD: Eradicating Translocon Components from the Outer Membrane of the Chloroplast

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Molecular Plant 2019年第4期12卷 467-469页

作者： Venkatasalam Shanmugabalaji Felix Kessler Laboratory of Plant Physiology University of Neuchatel 2000 Neuchatel Switzerland

Around 100 proteins are produced inside the chloroplast but the vast majority must be imported. These proteins are synthesized in the cytosol as preproteins with cleavable targeting sequences. Several plastid types other than chloroplasts exist. During plant development, one plastid type may be converted to another, a process referred to as plastid transition (Jarvis and Lopez-Juez, 2013). During plastid transitions, proteome remodeling occurs, and one set of imported proteins is replaced by another that is functionally adapted (Kleffmann et al., 2007). Moreover, plastid proteomes are known to be regulated in an environmentdependent fashion, and chloroplasts may respond to changing light conditions by regulating the composition and abundance of photosynthetic complexes.

关键词： CHLORAD Eradicating Translocon Components Outer Membrane Chloroplast

Experimental manipulation of reproductive tactics in Seba’s short-tailed bats:consequences on sperm quality and oxidative status

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Current Zoology 2019年第6期65卷 609-616页

作者： Magali MENIRI Florence GOHON Ophelie GNING Gaetan GLAUSER Armelle VALLAT Nicolas JFASEL Fabrice HELFENSTEIN Laboratory of Evolutionary Ecophysiology Institute of BiologyUniversity of NeuchatelSwitzerland neuchatel Platform of Analytical Chemistry University of NeuchatelSwitzerland Leibniz Institute for Zoo and Wildlife Research Germany

To reproduce,males have to fertilize the female’s eggs,sometimes in competition with ejaculates of other *** species where males display alternative reproductive tactics,whereby territorial males secure mating and non-territorial males have to sneak copulations,the latter might be expected to invest relatively more resources towards sperm quality compared with the territorial *** cells are especially vulnerable to oxidative stress,which reduces male ***,antioxidant resources are expected to modulate sperm quality,and might be allocated differently between reproductive *** test the link between reproductive tactics,redox profile and sperm quality,we experimentally induced changes in the reproductive tactics of 39 captive males Seba's short-tailed bats Carollia *** monitored the blood and ejaculate oxidative balance,and the sperm quality before,7 days and 21 days after the manipulation of reproductive *** ejaculates'oxidative damage was negatively related to sperm velocity,males exhibited similar blood and ejaculates redox profiles and similar sperm quality,regardless of their reproductive ***,these results arise as a consequence of some constraints having been lifted during the *** results also suggest that,in Seba's short-tailed bats,the expression of alternative reproductive tactics is not subjected to strong oxidative ***,our results could reflect an absence of trade-off between pre-and post-copulatory traits in harem males,as they could be selected to invest both in female attraction and sperm quality,as a consequence of their inability to fully monopolize females.

关键词： oxidative stress sperm competition alternative reproductive tactics Carollia perspicillata

Single-photon avalanche diode imagers in biophotonics:review and outlook

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Light(Science & Applications) 2019年第1期8卷 409-436页

作者： Claudio Bruschini Harald Homulle Ivan Michel Antolovic Samuel Burri Edoardo Charbon AQUA EPFLNeuchatelSwitzerland AQUA TU DelftDelftThe Netherlands

Single-photon avalanche diode(SPAD)arrays are solid-state detectors that offer imaging capabilities at the level of individual photons,with unparalleled photon counting and time-resolved *** fascinating technology has progressed at a very fast pace in the past 15 years,since its inception in standard CMOS technology in 2003.A host of architectures have been investigated,ranging from simpler implementations,based solely on off-chip data processing,to progressively“smarter”sensors including on-chip,or even pixel level,time-stamping and processing *** the technology has matured,a range of biophotonics applications have been explored,including(endoscopic)FLIM,(multibeam multiphoton)FLIM-FRET,SPIM-FCS,super-resolution microscopy,time-resolved Raman spectroscopy,NIROT and *** will review some representative sensors and their corresponding applications,including the most relevant challenges faced by chip designers and ***,we will provide an outlook on the future of this fascinating technology.

关键词： image photon simpler

Revisiting the trail pheromone components of the red imported fire ant, Solenopsis invicta Buren

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Insect Science 2023年第1期30卷 161-172页

作者： Tian Xu Nuo Zhang Meng Xu Gaetan Glauser Ted C.J.Turlings Li Chen State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina School of Life Sciences Institute of Life Science and Green DevelopmentHebei UniversityBaodingHebei ProvinceChina College of Forestry Nanjing Forestry UniversityNanjingChina School of Agriculture Yangtze UniversityJingzhouChina neuchatel Platform of Analytical Chemistry University of NeuchatelNeuchatelSwitzerland Laboratory of Fundamental and Applied Research in Chemical Ecology University of NeuchatelSwitzerland

Ants use species-specific trail pheromones to coordinate their sophisticated foraging *** the past decades,many trail pheromone components with various structures have been identified in ants,including the red imported fire ant,Solenopsis invicta,a notorious invasive species *** compounds,Z,E-(ZEF)and E,E-α-farnesene(EEF),Z,E-(ZEHF)and E,E-α-homofarnesene(EEHF),have been reported as components of *** trail ***,another study reported an analog ofα-farnesene,Z,Z,Z-allofarnesene,as a key trail pheromone *** contrasting results caused some uncertainty about the trail pheromone composition in *** this study,we synthesized ZEF and EEF,ZEHF and EEHF,and reanalyzed the chemicals in the Dufour gland extract and in the trail pheromone fraction of *** worker body *** reported isomers of farnesene and homofarnesene were detected and showed trail-following activity,with ZEF as the major compound,while no allofarnesene was found,neither in the Dufour gland extract nor in the whole-body *** results confirm ZEF and EEF,ZEHF and EEHF as trail pheromone components of ***.

关键词： allofarnesene Dufour gland α-farnesene α-homofarnesene synthesis trail-following

The Rice RMR1 Associates with a Distinct Prevacuolar Compartment for the Protein Storage Vacuole Pathway

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Molecular Plant 2011年第5期4卷 854-868页

作者： Yun Shen Junqi Wang Yu Ding Sze Wan Lo Guillaume Gouzerh Jean-Marc Neuhau Liwen Jiang School of Life Sciences Centre for Cell and Developmental Biology The Chinese University of Hong Kong Shatin New Territories Hong Kong China Laboratory of Cell and Molecular Biology University of Neuchatel CH-2000 Neuchatel Switzerland

Transport of vacuolar proteins from Golgi apparatus or trans-Golgi network （TGN） to vacuoles is a receptor-mediated process via an intermediate membrane-bound prevacuolar compartment （PVC） in plant cells. Both vacuolar sorting receptor （VSR） and receptor homology region-transmembrane domain-RING-H2 （RMR） proteins have been shown to function in transporting storage proteins to protein storage vacuole （PSV）, but little is known about the nature of the PVC for the PSV pathway. Here, we use the rice RMR1 （OsRMR1） as a probe to study the PSV pathway in plants. Immunogold electron microscopy （EM） with specific OsRMR1 antibodies showed that OsRMR1 proteins were found in the Golgi apparatus, TGN, and a distinct organelle with characteristics of PVC in both rice culture cells and developing rice seeds, as well as the protein body type II （PBII） or PSV in developing rice seeds. This organelle, also found in both tobacco BY-2 and Arabidopsis suspension cultured cells, is morphologically distinct from the VSR-positive multivesicular lytic PVC or multivesicular body （MVB） and thus represent a PVC for the PSV pathway that we name storage PVC （sPVC）. Further in vivo and in vitro interaction studies using truncated OsRMR1 proteins secreted into the culture media of transgenic BY-2 suspension cells demonstrated that OsRMR1 functions as a sorting receptor in transporting vicilin-like storage proteins.

关键词： PSV RMR storage PVC sorting receptor transport pathway.

Effects of seed type and bruchid genotype on the performance and oviposition behavior of Zabrotes subfasciatus （Coleoptera： Bruchidae）

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Insect Science 2006年第4期13卷 309-318页

作者： ERICK D. M. CAMPAN BETTY BENREY Labomtory of Evolutionary Entomology Institute of Zoology University of Neuchatel Neuchatel Switzerland Laboratoire Dynamique de la Biodiversité Université Paul Sabatier Toulouse France

The effect of different bean varieties on the performance of the bruchid beetle Zabrotes subfasciatus Boheman （Coleoptera： Bruchidae）, was determined by using wild and cultivated seeds of the genus Phaseolus. Results showed that the quality of the host plant affected the performance and the oviposition behavior of female beetles. Overall, bruchid performance was higher on cultivated seeds than on wild seeds. It was also found that the oviposition behavior and the performance of their offspring differed between females that originated from wild versus cultivated seeds. We also demonstrated the importance of a genetic component in bruchid performance： longevity, fecundity, larval development, adult size, and the sex ratio of the progeny varied according to their matemal lineage （‘family＇）. For example, on the same host type, some females laid twice as many eggs as females from other‘families＇, and the sex ratio among the offspring correlated with that of their mother. Thus, the performance and behavior of Z. subfasciatus are not only affected by environmental factors such as the quality of the seeds on which they develop, but also have a genetic basis which can counterbalance a less suitable quality of the host plant. For a crop pest such as Z. subfasciatus, its ability to survive and adapt on host plants of differing quality may be an important attribute to consider for pest management.

关键词： bean beetles domestication host plant quality larval performance oviposition behavior

Root symbionts： Powerful drivers of plant above- and belowground indirect defenses

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Insect Science 2017年第6期24卷 947-960页

作者： Sergio Rasmann Alison Bennett Arjen Biere Alison Karley Emilio Guerrieri Institute of Biology University of Neuchatel Neuchatel Switzerland Department of Ecological Sciences James Hutton Institute Dundee UK Netherlands Institute of Ecology Wageningen the Netherlands Institute for Sustainable Plant Protection National Research Council of Italy Portici Italy

Soil microbial mutualists of plants, including mycorrhizal ftmgi, non- mycorrhizal fungi and plant growth promoting rhizobacteria, have been typically characterized for increasing nutrient acquisition and plant growth. More recently, soil microbes have also been shown to increase direct plant defense against above- and below- ground herbivores. Plants, however, do not only rely on direct defenses when attacked, but they can also recruit pest antagonists such as predators and parasitoids, both above and belowground, mainly via the release of volatile organic compounds （i.e., indirect defenses）. In this review, we illustrate the main features and effects of soil microbial mutualists of plants on plant indirect defenses and discuss possible applications within the framework of sustainable crop protection against root- and shoot-feeding arthropod pests. We indicate the main knowledge gaps and the future challenges to be addressed in the study and application of these rnultifaceted interactions.

关键词： arbuscular mycorrhizal fungi crop protection entomopathogenic nematodes plant growth promoting rhizobacteria Trichoderma