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Influence of manufacturing process-induced geometrical defects on the energy absorption capacity of polymer lattice structures

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Defence Technology（防务技术） 2024年第5期35卷 47-59页

作者： Alexandre Riot Enrico Panettieri Antonio Cosculluela Marco Montemurro Universite de Bordeaux Arts et Metiers Institute of TechnologyCNRSINRABordeaux INPHESAM UniversiteI2M UMR 5295F-33405 TalenceFrance French Atomic Energy Commission Route des GargailsCedexF-33114Le BarpFrance

Modern additive manufacturing processes enable fabricating architected cellular materials of complex shape,which can be used for different purposes.Among them,lattice structures are increasingly used in applications requiring a compromise among lightness and suited mechanical properties,like improved energy absorption capacity and specific stiffness-to-weight and strength-to-weight ratios.A dedicated modeling strategy to assess the energy absorption capacity of lattice structures under uni-axial compression loading is presented in this work.The numerical model is developed in a non-linear framework accounting for the strain rate effect on the mechanical responses of the lattice structure.Four geometries,i.e.,cubic body centered cell,octet cell,rhombic-dodecahedron and truncated cuboctahedron 2+,are investigated.Specifically,the influence of the relative density of the representative volume element of each geometry,the strain-rate dependency of the bulk material and of the presence of the manufacturing process-induced geometrical imperfections on the energy absorption capacity of the lattice structure is investigated.The main outcome of this study points out the importance of correctly integrating geometrical imperfections into the modeling strategy when shock absorption applications are aimed for.

关键词： Lattice structures Architected cellular materials Dynamic simulation Energy absorption Geometrical imperfection Additive manufacturing

Sexual audience affects male's reproduction investment without consequences on reproductive outputs

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Insect Science 2022年第4期29卷 1170-1180页

作者： Philippe Louâpre Karen Muller Soline Bettencourt-Amarante Denis Thiery Jérôme Moreau umr CNRS 6282 Biogeosciences UniversitéBourgogne Franche-ComtéDijonFrance inra umr 1065 Santéet Agroecologie du Vignoble Institut des Science de la Vigne et du VinVillenave d'OrnonCedexFrance inra umr 1065 SaveUniversitéde BordeauxBordeaux Sciences AgroVillenave d'OrnonCedexFrance

Males evolved plastic strategies to respond to male-male competition and exhibit adaptive traits and behaviors maximizing their access to the females and limiting sperm competition.Mating behaviors allow males to express quick responses to current sexual audience,that is,the number of nearby conspecifics prone to mate.In contrast,physiological responses are frequently delayed because they are constrained by the time and resources having to be mobilized to produce and export sperm and associated products.This is especially critical in species for which males produce spermatophores.Here we investigated in what extend moth males(the tortricid moth Lobesia botrana)producing spermatophores exhibit plastic behavioral and physiological responses to different sexual audiences before and during mating and the consequences for their reproductive output.We found that males adjusted their mating behaviors and spermatophore size to a potentially elevated risk of sperm competition perceived before mating.In addition,males responded to the closed presence of females during mating by reducing their mating duration.Surprisingly,the various behavioral and physiological responses we highlighted here were not fully reflected in their reproductive performance as we did not reveal any effect on fecundity and fertility of their mate.The selective pressure exerted on males experiencing male-male competition could thus be sufficient to trigger adjustment in male mating behaviors but constrains physiological responses according to the perception of competition.

关键词： Lobesia borrund male-male compeition mating behavior sexual conflict sexual scletion sperm competition

Littoral landforms of Lake Hulun and Lake Buir(China and Mongolia):Wind-driven hydro-sedimentary dynamics and resulting clastics distribution

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Journal of Palaeogeography 2024年第2期13卷 309-326页

作者： Li Wang Mathieu Schuster Shi-Wei Xin Florin Zainescu Xin-Yu Xue Joep Storms Jan-Hendrik May Alexis Nutz Helena van der Vegt Guilherme Bozetti Zai-Xing Jiang School of Energy Resources China University of Geosciences(Beijing)Beijing100083China Universite de Strasbourg CNRSENGEESInstitut Terre et Environnement de StrasbourgUMR 70635 Rue DescartesStrasbourgFrance Tamsag Mongolia(XIX)Ltd. PetroChinaDaqing 163000China CEREGE Aix-Marseille UniversitéCNESIRDCollege de FranceINRAAix en ProvenceFrance School of Marine Science Sun Yat-sen UniversityZhuhai 519083China Delft University of Technology Department of Geoscience and EngineeringDelfthe Netherlands School of Geography Earth and Atmospheric SciencesUniversity of Melbourne253 Elgin St.CarltonVIC 3053Australia Deltares Delfthe Netherlands SCMF Faculty of GeographyUniversity of Bucharest1 N.Balcescu Blv.BucharestRomania

Two rectangular-shaped lakes,Lake Hulun and Lake Buir,located at the boundary between China and Mongolia,only c.75 km apart and therefore experiencing similar wind fields,have been studied based on satellite images and field surveys in order to compare their geomorphological and sedimentological characteristics.The wind-driven hydrodynamics,which have a significant effect on the development of littoral landforms and on sediment distribution,have been discussed for the two similar lakes that experienced a prevailing wind perpendicular to their long axis.A conceptual model related to wind-driven water bodies and sediment distribution is proposed.Wave-influenced to wave-dominated deltas,beaches,spits,and eolian dune deposits develop around these two lakes,with a strikingly similar distribution pattern.These features locally inform the longshore drift and help reconstruct the water circulation induced by wind forcing.Under the NW prevailing wind regime,the spits developed on the SW coast with a NW—SE extension,which was influenced by the NW—SE longshore currents.The same influence was observed in the delta extension in the NE area.The differences lie in the presence of fan deltas in the NW region of Lake Hulun,but not in Lake Buir.Additionally,the width of the beach and eolian deposits on the downwind coast of Lake Hulun is three times greater than that of Lake Buir which were caused by the differences in sediment supply and wind fetch between the two lakes.Lake Hulun and Lake Buir provide two reliable examples to understand the relationship among the wind field,provenance,hydrodynamics,landforms,and asymmetrical distribution of clastics in elongated lakes.They also represent relevant modern analogs,which may also be of guiding significance to wind-driven sand body prediction in lacustrine basins.

关键词： Wind-driven lakes Fetch Sedimentary facies Hydrodynamics Geomorphology Spits Shoreline Lake Hulun Lake Buir

Vespa velutina nest distribution at a local scale： An 8-year survey of the invasive honeybee predator

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Insect Science 2017年第4期24卷 663-674页

作者： Karine Monceau Denis Thiery inra UMR 1065 Sante et Agroecologie du Vignoble Bordeaux Sciences Agro ISVV F-33883 Villenave d'Omon Cedex France

Vespa velutina is an invasive species that was observed for the first time in France and Europe in 2004, which rapidly threatened domestic honeybees with active predation. For the first time in this study, we analyzed the distribution of V. velutina nests at a local scale to understand the pattern of nesting, and in 8 years of monitoring, a total of 528 nests were surveyed. With the exception of 2 years, the nests of V. velutina were randomly distributed within the monitored area, which suggested that intraspecific competition for nesting sites and/or food was unlikely. When the data for all years were combined, an aggregated distribution of nests at the seafront in the vicinity of the oyster farm and sportfishing activities was observed. This distribution suggested that seafood, attractive to vespids, might provide a valuable alternative food source that favored colony development. We also tested the effect of spring queen trapping of V. velutina on the distribution of nests in 2014, which was the year with the greatest number of colonies within the area; the position of the traps did not influence the distribution of the nests. For the first time, this study showed that （i） intraspecific competition was unlikely to be a mechanism for population regulation, （ii） some areas were more likely favored for hornet nests, and （iii） spring queen wasp trapping was inefficient as a method to limit the distribution of the V. velutina population.

关键词： intraspecific competition nesting habits spring queen trapping yellow-legged hornet

Delayed sexual maturity in males of Vespa velutina

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Insect Science 2018年第4期25卷 679-689页

作者： Juliette Poidatz Christophe Bressac Olivier Bonnard Denis Thiery inra UMR1065 Santé et Agroecologie du Vignoble ISVV Bordeaux Sciences Agro Villenave d'Omon France IRBI Universite Francois Rabelais UMR CNRS 7261 Tours France

Vespa velutina var nigrithorax （Lepelletier, 1835） is an invasive predator of bees accidentally introduced in France in 2004, and it is having a serious impact on apiculture and ecosystems. Studying the reproduction of an invasive species is key to assess its population dynamic. This study explores the sexual maturation of IT. velutina males and the evolution of their fertility. The main studied parameters were physiologic （spermiogenesis, spermatogenesis） and anatomic （testes size and structure, head width）. Two populations of males were described based on their emergence period： early males in early summer or classic males in autumn. Each testis has an average of 108 testicular follicles. Spermatogenesis is synchronous, with only 1 sperm production wave, and completed, on average, at 10.3 d after emergence with the degeneration of the testes. The sperm counts in seminal vesicles of mature males are 3 x 106 in October/November and 0.8 ~ 106 in June. In com- parison, females store 0.1 x 106 sperm in their spermathecae. The early males emerged from colonies made by fertilized queens. The reproductive potential of these early males seemed limited, and their fimction in the colony is discussed. The sperm stock evolution in autumn males suggests the occurrence of a reproductive pattern of male competition for the access to females and a single copulation per male. The synchronicity of male and foundress emergences and sexual maturation is of primary importance for the mating success and the future colony development.

关键词： male fertility seminal vesicles spermiogenesis sperm stock testis Vespidae yellow-legged hornet

Behavioral syndrome in a native and an invasive hymenoptera species

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Insect Science 2015年第4期22卷 541-548页

作者： Karine Monceau Jerome Moreau Juliette Poidatz Olivier Bonnard Denis Thiery inra UMR 1065 Sante et Agroecologie du Vignoble F-33883 Villenave d'Omon France ISVV umr 1065 Sante et Agroecologie du Vignoble Bordeaux Sciences Agro Universite de Bordeaux F-33883 Villenave d'Omon France Universite de Bourgogne umr CNRS 6282 Biogeosciences 6 bd Gabriel 21000 Dijon France

Recent studies have focused on the role of behavior in biological invasions. Individuals may differ consistently in time for several behavioral traits （personality） which covary （behavioral syndrome） resulting in different behavioral types, some of them favoring invasion. Social hymenopterans have a strong potential to be invaders and their success depends primarily on the foundresses＇ ability to found viable colonies. They are expected to be active, explorative and bold for optimally establishing their nest. In Europe, 2 homet species coexist： the native Vespa crabro and the invasive Vespa velutina. These 2 species may compete for nesting sites and we suggest that the initial success of V. velutina has been favored by its behavior in outperforming V. crabro for the traits involved in nest initiation. Here, we （i） defined the personality of V. crabro and V：. velutina, （ii） tested for the existence of behavioral syndrome in these species, and （iii） compared their performances using an open-field test. Our results show that V. crabro foundresses behave consistently but not V. velutina; this lack of consistency being mainly due to reduced variance among individuals. This result questions the possibility of detecting consistent behavioral differences in species having recently undergone a strong bottleneck. Both species exhibit the same correlations between activity, boldness and exploration and V. velutina clearly outperforms 14. crabro for all traits. Our results suggest that activity, boldness, and exploration are implicated in both hornet nest initiation and invasion process which contributed to explain why social hymenopterans are so successful at colonization.

关键词： animal personality biological invasion invasion syndrome Vespa crabro Vespa velutina Vespidae

Spatial distribution of Vespa velutina individuals hunting at domestic honeybee hives： heterogeneity at a local scale

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Insect Science 2014年第6期21卷 765-774页

作者： Karine Monceau Olivier Bonnard Jerome Moreau Denis Thiery inra UMR1065 Sante et Agroecologie du Vignoble F-33883 Villenave d'Omon ISVV UMR1065 Sante et Agroecologie du Vignoble Bordeaux Sciences Agro Universite de Bordeaux F-33883 Villenave d'Omon Equipe Ecologie Evolutive UMR 6282 Biogeosciences 6 Bd Gabriel Universite de Bourgogne F-21000 Dijon France

Since its recent introduction into Europe, the yellow-legged hornet, Vespa velutina, has become a major predator of the domestic honeybee, Apis mellifera, but little is known about its hunting behavior. We studied V. velutina hunting behavior by a capture- mark-recapture procedure in an experimental apiary. A total of 360 hornets were captured and tagged, and we determined：（i） the number of hornets visiting the apiary and the changes in time, （ii） the average number of individual visits per half-day and the time elapsed between consecutive recaptures, and （iii） the individual and global distribution of the hornets in the apiary. More than 50% of the marked hornets were recaptured at least once, this increased to 74% in considering the first marked individuals. We estimated 350 hornets visiting the patch daily with at least 1 visit per half-day. The number of marked hornets decreased over time while the number of unmarked ones increased, suggesting a turnover of individuals. The reduction of the delay between consecutive visits indicates that hornets became more efficient over time. Most of the hornets （88%） were recaptured in front of different hives but, overall, the global distribution was aggregative. Hornets were mainly recaptured in front of 1 hive which was neither the smallest nor the biggest colony, suggesting that the major cue used by hornets is not the amount of food. We hypothesize that the defensive behavior of the honeybee colony could explain our results which may be promising to further studies.

关键词： Apis mellifera capture-mark-recapture learning predation Vespidae yellow-legged hornet

Proteomic composition of the acrostyle＂ Novel approaches to identify cuticular proteins involved in virus-insect interactions

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Insect Science 2017年第6期24卷 990-1002页

作者： Craig Graham Webster Maelle Thillier Elodie Pirolles Bastien Cayrol Stephane Blanc Marilyne Uzest inra UMR 0385 BGPI CIRAD-INRA-Montpellier SupAgro Campus International de Baillarguet Montpellier Cedex France

The acrostyle is a distinct anatomical region present on the cuticle at the inner face of the common food/salivary canal at the tip of aphid maxillary stylets. This conserved structure is of particular interest as it harbors the protein receptors of at least l plant virus, Cauliflower mosaic virus＇, and presumably has other roles in plant-insect interactions. Previously we reported immunolabeling of a highly conserved motif of cuticular proteins from the CPR family （named for the presence of a Rebers and Riddiford consensus） within the acrostyle. Here we report the development of novel tools to further study the proteomic composition of this region and to identify proteins involved in insect- virus interactions. Using a series of antibodies against cuticular proteins from the RR-2 subfamily, we identified additional peptides present within the acrostyle. Our results demonstrated that the acrostyle is a complex structure containing multiple domains of cuticular proteins accessible for interaction. In addition, an array of overlapping peptides,which covers the diversity of the majority of the RR-2 subfamily, was ~tevelopect as a generic tool to characterize cuticular protein/pathogen interactions. Upon probing this array with Cucumber mosaic virus particles, consensus peptide sequences from hybridizing peptides were identified. Use of these novel tools has extended our knowledge of the proteomic composition of insect maxillary stylets and identified sequences that could be involved in virus binding, thus contributing to further elucidation of the various properties and functions of the acrostyle.

关键词： acrostyle aphid cuticular protein immunolabeling peptide array stylet

Mucosal healing progression after acute colitis in mice

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World Journal of Gastroenterology 2019年第27期25卷 3572-3589页

作者： Sandra Vidal-Lletjós Mireille Andriamihaja Anne Blais Marta Grauso Patricia Lepage Anne-Marie Davila Claire Gaudichon Marion Leclerc Francois Blachier Annaig Lan umr PNCA AgroParisTechINRAUniversite Paris-SaclayParis 75005France umr MICALIS INRAUniversite Paris-SaclayJouy-en-Josas 78350France

BACKGROUND Mucosal healing has become a therapeutic goal to achieve stable remission in patients with inflammatory bowel diseases. To achieve this objective, overlapping actions of complex cellular processes, such as migration, proliferation, and differentiation, are required. These events are longitudinally and tightly controlled by numerous factors including a wide range of distinct regulatory proteins. However, the sequence of events associated with colon mucosal repair after colitis and the evolution of the luminal content characteristics during this process have been little studied.AIM To document the evolution of colon mucosal characteristics during mucosal healing using a mouse model with chemically-induced colitis.METHODS C57 BL/6 male mice were given 3.5% dextran sodium sulfate(DSS) in drinking water for 5 d. They were euthanized 2(day 7), 5(day 10), 8(day 13), and 23(day28) d after DSS removal. The colonic luminal environment and epithelial repair processes during the inflammatory flare and colitis resolution were analyzed with reference to a non-DSS treated control group, euthanized at day 0. Epithelial repair events were assessed histo-morphologically in combination with functional permeability tests, expression of key inflammatory and repairing factors, and evaluation of colon mucosa-adherent microbiota composition by 16 S rRNA sequencing.RESULTS The maximal intensity of colitis was concomitant with maximal alterations of intestinal barrier function and histological damage associated with goblet cell depletion in colon mucosa. It was recorded 2 d after termination of the DSStreatment, followed by a progressive return to values similar to those of control mice. Although signs of colitis were severe(inflammatory cell infiltrate, crypt disarray, increased permeability) and associated with colonic luminal alterations(hyperosmolarity, dysbiosis, decrease in short-chain fatty acid content), epithelial healing processes were launched early during the inflammatory flare with increased gene expression of cert

关键词： Colon luminal environment Dextran sodium sulfate-induced colitis Dysbiosis Epithelial repair Acute colitis