Etude de faisabilité d'une startup active dans la distribution de produits alimentaires locaux en entreprise

Se sentir chez un maraîcher dans sa propre entreprise, voilà le défi qui nous a poussé à réaliser ce travail de bachelor consistant en une étude de faisabilité. Cette idée nous est venue lors d’un cours dispensé à la Haute Ecole de Gestion de Genève (Entrepreneuriat social et développement durable). Nous avions alors esquisser un projet de livraison de produits locaux en entreprise. Nous étions très motivés et désireux de pouvoir approfondir cette idée et d’estimer sa viabilité. Nous nous sommes donc intéressés aux différents aspects de ce projet et avons réussi à formuler une offre : une entreprise active à Genève proposant des distributeurs automatiques de fruits et légumes directement installés en entreprise livrés deux fois par semaine. Cette idée n’a encore jamais été vue en Suisse et pourrait bien révolutionner le système de distribution pour les producteurs locaux. Ce concept s’inscrit dans une démarche sociale et durable, dans le sens où elle fourni une externalité sociétale positive et minimise son impact environnemental (circuit-court). Pour ce faire, nous nous sommes basés sur huit points qu’un entrepreneur « social » devait aborder pour regarder la cohérence et la viabilité de son entreprise : le problème sociétal auquel nous répondons et la solution que nous apportons, la valeur ajoutée de notre démarche, notre stratégie de croissance, le développement avec d’autre parties-prenantes de la société, les risques liés à notre activité et notre impact sociétal, notre modèle organisationnel, la cohérence avec les critères d’adhésion au réseau APRES-GE et enfin notre modèle économique. Ces différents points nous ont amené à avoir une vision à 360° sur un projet comme celui-ci. A travers les pages de ce travail de bachelor, le lecteur pourra ainsi voir quels facteurs d’influences peuvent jouer en faveur de notre idée et quels points la mettent plus en difficulté

Mechanical Behavior of Three-Dimensional Braided Nickel-Based Superalloys Synthesized via Pack Cementation

Braided tubes of Ni-based superalloys are fabricated via three-dimensional (3-D) braiding of ductile Ni-20Cr (wt pct) wires followed by post-textile gas-phase alloying with Al and Ti to create, after homogenization and aging, γ/γ′ strengthened lightweight, porous structures. Tensile tests reveal an increase in strength by 100 MPa compared to as-braided Ni-20Cr (wt pct). An interrupted tensile test, combined with X-ray tomographic scans between each step, sheds light on the failure behavior of the braided superalloy tubes

PeroxiBase: a database with new tools for peroxidase family classification

Peroxidases (EC 1.11.1.x), which are encoded by small or large multigenic families, are involved in several important physiological and developmental processes. They use various peroxides as electron acceptors to catalyse a number of oxidative reactions and are present in almost all living organisms. We have created a peroxidase database (http://peroxibase.isb-sib.ch) that contains all identified peroxidase-encoding sequences (about 6000 sequences in 940 organisms). They are distributed between 11 superfamilies and about 60 subfamilies. All the sequences have been individually annotated and checked. PeroxiBase can be consulted using six major interlink sections ‘Classes', ‘Organisms', ‘Cellular localisations', ‘Inducers', ‘Repressors' and ‘Tissue types'. General documentation on peroxidases and PeroxiBase is accessible in the ‘Documents' section containing ‘Introduction', ‘Class description', ‘Publications' and ‘Links'. In addition to the database, we have developed a tool to classify peroxidases based on the PROSITE profile methodology. To improve their specificity and to prevent overlaps between closely related subfamilies the profiles were built using a new strategy based on the silencing of residues. This new profile construction method and its discriminatory capacity have been tested and validated using the different peroxidase families and subfamilies present in the database. The peroxidase classification tool called PeroxiScan is accessible at the following address: http://peroxibase.isb-sib.ch/peroxiscan.ph

Micro-Channel Plate Detectors Based on Hydrogenated Amorphous Silicon

A new type of micro-channel plate detector based on hydrogenated amorphous silicon is proposed which overcomes the fabrication and performance issues of glass or bulk silicon ones. This new type of detectors consists in 80-100 μm thick layers of amorphous silicon which are micro-machined by deep reactive ion etching to form the channels. This paper focuses on the structure and fabrication process and presents first results obtained with test devices on electron detection which demonstrate amplification effects. Fabrication and performance issues are also discussed

Thin-film silicon detectors for particle detection

Integrated particle sensors have been developed using thin-film on ASIC technology. For this purpose, hydrogenated amorphous silicon diodes, in various configurations, have been optimized for particle detection. These devices were first deposited on glass substrates to optimize the material properties and the dark current of very thick diodes (with thickness up to 50 μm). Corresponding diodes were later directly deposited on CMOS readout chips. These integrated particle sensors have been characterized using light pulse illumination and beta particle irradiation from 63Ni and 90Sr sources. Direct detection of single low- and high-energy beta particles have been demonstrated. The application of this new integrated particle sensor concept for medical imaging is also discussed

A Hydrogenated amorphous silicon detector for Space Weather Applications

The characteristics of a hydrogenated amorphous silicon (a-Si:H) detector are presented here for monitoring in space solar flares and the evolution of large energetic proton events up to hundreds of MeV. The a-Si:H presents an excellent radiation hardness and finds application in harsh radiation environments for medical purposes, for particle beam characterization and in space weather science and applications. The critical flux detection threshold for solar X rays, soft gamma rays, electrons and protons is discussed in detail.Comment: 32 pages, 13 figures, submitted to Experimental Astronom

Large-scale genome sequencing of mycorrhizal fungi provides insights into the early evolution of symbiotic traits

Mycorrhizal fungi are mutualists that play crucial roles in nutrient acquisition in terrestrial ecosystems. Mycorrhizal symbioses arose repeatedly across multiple lineages of Mucoromycotina, Ascomycota, and Basidiomycota. Considerable variation exists in the capacity of mycorrhizal fungi to acquire carbon from soil organic matter. Here, we present a combined analysis of 135 fungal genomes from 73 saprotrophic, endophytic and pathogenic species, and 62 mycorrhizal species, including 29 new mycorrhizal genomes. This study samples ecologically dominant fungal guilds for which there were previously no symbiotic genomes available, including ectomycorrhizal Russulales, Thelephorales and Cantharellales. Our analyses show that transitions from saprotrophy to symbiosis involve (1) widespread losses of degrading enzymes acting on lignin and cellulose, (2) co-option of genes present in saprotrophic ancestors to fulfill new symbiotic functions, (3) diversification of novel, lineage-specific symbiosis-induced genes, (4) proliferation of transposable elements and (5) divergent genetic innovations underlying the convergent origins of the ectomycorrhizal guild. Mycorrhizal symbioses have evolved repeatedly in diverse fungal lineages. A large phylogenomic analysis sheds light on genomic changes associated with transitions from saprotrophy to symbiosis, including divergent genetic innovations underlying the convergent origins of the ectomycorrhizal guild.Peer reviewe