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Background Following the SARS-CoV-2 Omicron variant spread, the use of unsupervised antigenic rapid diagnostic tests (self-tests) increased. Aim This study aimed to measure self-test uptake and factors associated with self-testing. Methods In this cross-sectional study from 20 January to 2 May 2022, the case series from a case–control study on factors associated with SARS-CoV-2 infection were used to analyse self-testing habits in France. A multivariable quasi-Poisson regression was used to explore the variables associated with self-testing among symptomatic cases who were not contacts of another infected individual. The control series from the same study was used as a proxy for the self-test background rate in the non-infected population of France. Results During the study period, 179,165 cases who tested positive through supervised tests were recruited. Of these, 64.7% had performed a self-test in the 3 days preceding this supervised test, of which 79,038 (68.2%) were positive. The most frequently reported reason for self-testing was the presence of symptoms (64.6%). Among symptomatic cases who were not aware of being contacts of another case, self-testing was positively associated with being female, higher education, household size, being a teacher and negatively associated with older age, not French by birth, healthcare-related work and immunosuppression. Among the control series, 12% self-tested during the 8 days preceding questionnaire filling, with temporal heterogeneity. Conclusion The analysis showed high self-test uptake in France with some inequalities which must be addressed through education and facilitated access (cost and availability) for making it a more efficient epidemic control tool.

In this study, proton-irradiated tungsten targets, up to 2.6 GeV, were investigated for the purpose of the experimental cross-section measurements. Radiochemical separation methods were applied to isolate the residual long-lived alpha-emitters 148Gd, 154Dy, and 146Sm and the beta-emitters 129I and 36Cl from proton-irradiated tungsten targets. The molecular plating technique has been applied to prepare 148Gd, 154Dy, and 146Sm samples for alpha-spectrometry. Production cross-sections of 129I and 36Cl were determined by means of accelerator mass spectrometry. The results are compared with theoretical predictions, obtained with the INCL++–ABLA07 codes, showing good agreement for 36Cl and 148Gd, while a factor of 4 difference was observed for 154Dy, similar to the results obtained for tantalum targets., Analytical Chemistry, 93 (31), ISSN:1520-6882, ISSN:0003-2700

Multidisciplinary design optimization methods aim at adapting numerical optimization techniques to the design of engineering systems involving multiple disciplines. In this context, a large number of mixed continuous, integer and categorical variables might arise during the optimization process and practical applications involve a large number of design variables. Recently, there has been a growing interest in mixed variables constrained Bayesian optimization but most existing approaches severely increase the number of the hyperparameters related to the surrogate model. In this paper, we address this issue by constructing surrogate models using less hyperparameters. The reduction process is based on the partial least squares method. An adaptive procedure for choosing the number of hyperparameters is proposed. The performance of the proposed approach is confirmed on analytical tests as well as two real applications related to aircraft design. A significant improvement is obtained compared to genetic algorithms. https://arc.aiaa.org/doi/pdf/10.2514/6.2022-0082

The demand for cocoa has increased over the past years following the growth of cocoa-based products linked to the rise in living standard in highly populated countries. Cacao industry is therefore currently facing the dilemma of producing more cacao while ensuring its sustainability. Cacao monocrops and agroforestry systems (AFS) are two contrasting ways to produce cocoa, yet their impact on yields, contribution to farmer livelihood, cocoa quality remains understudied. Therefore, we reviewed existing literature comparing (1) monocrop cacao farming systems with (2) simple or (3) complex AFS. We found 19 comparisons of the cocoa yields in monocrops and simple AFS and 20 comparisons of monocrop and complex AFS. Three main research findings derive from this work. First, in about one third of cases, cacao trees yield more (or equally) in AFS than in monocrops. However, when considering only simple AFS, cacao trees yield more or equal to cacao monocrop in 52% of the cases. Second, cocoa AFS yields an average of 14% less than cacao monocrop. Yet, on average simple AFS yielded 2% less than cacao monocrops. Finally, there are too little elements to draw conclusions about the nexus between cocoa quality and cacao tree cultivation system.

Increasing the wing aspect ratio appears as a straightforward way to improve aerodynamic performance of transport aircraft by reducing the lift-induced drag component. However, it comes at the price of a direct negative impact on the wing structural weight which is necessary to sustain aerodynamic loads in the case of a conventional cantilever wing. The strut-braced wing concept allows to reduce the flexural moment to be carried out by the inner-wing structure and therefore limits the weight penalty as aspect ratio is increased. A multidisciplinary evaluation of the potential benefits at aircraft level of High Aspect Ratio, Strut Braced Wing concept is presented. It relies on a multi-fidelity design approach in which an Overall Aircraft Conceptual Design framework is combined with high-fidelity aerodynamic and structural analyses to provide accurate physical information to the conceptual design process. This paper describes the tools, framework and approach used to combine OACD with high-fidelity CFD and CSM analyses and illustrates the first results of its application to design a HAR-SBW aircraft concept which are compared to a conventional tube-and-wing aircraft designed for the same mission., Réduire l'empreinte environnementale de l'aviation et surtout son impact sur le changement climatique est aujourd'hui devenu l'enjeu majeur de l'industrie aéronautique. Dans ce contexte, la Commission européenne s'est fixé des objectifs ambitieux pour l'aviation définis dans le « Fligthpath 2050 », notamment une réduction de 75 % des émissions de CO2 et de 90 % des émissions de NOx, ainsi qu'une réduction de 65 % du bruit. Atteindre de tels objectifs ne sera probablement possible que grâce à des évolutions radicales de l'architecture de l'avion, du système de propulsion et de l'introduction de technologies de rupture. Pour ce qui concerne l'architecture de l'avion, le Blended Wing Body (BWB) et le Strut-Braced Wing (SBW) semblent aujourd'hui être les deux alternatives les plus prometteuses à la configuration classique "Twin Underwing Turbofan Tube-and-Wing" qui est devenue prédominante. solution au cours des dernières décennies. Le BWB et le Hybrid Wing Body sont actuellement étudiés dans le cadre de plusieurs efforts de recherche importants en Europe, aux États-Unis et en Chine. Le présent article présente des enquêtes sur la configuration SBW. La principale justification de la configuration SBW est de permettre une augmentation significative du rapport d'aspect de l'aile (AR) pour améliorer les performances globales de l'avion grâce à des gains d'efficacité aérodynamique sans l'énorme augmentation du poids de l'aile dont souffrirait une aile en porte-à-faux d'un AR similaire. Ceci est obtenu grâce à une réduction du moment de flexion dans le caisson de voilure interne permise par une traction de la jambe de force à sa jonction avec l'aile. Cela permet de réduire la taille des composants structurels du caisson de voilure dans l'aile intérieure qui sont principalement dimensionnés par le moment de flexion dans le cas d'une aile en porte-à-faux.Ce concept peut être utilisé pour augmenter l'allongement de l'aile et profiter d'une réduction de la traînée aérodynamique (en réduisant réellement la traînée induite par la portance) tout en contenant l'augmentation du poids structurel de l'aile associée à une envergure plus élevée (impliquant un moment de flexion plus élevé dans l'aile centrale -boîte). Par conséquent, l'ajout d'une jambe de force, ou plus généralement d'une structure en treillis, ouvre un degré de liberté supplémentaire pour le concepteur afin de mieux exploiter les ailes à rapport d'aspect élevé au niveau global de l'avion en réalisant un nouveau compromis optimal (par rapport au cantilever, sans jambe de force, aile) entre l'efficacité aérodynamique et le poids de l'aile.De tels compromis pour le concept d’aile haubanée ont déjà été étudiés à l'ONERA dans le projet ALBATROS. Plus récemment, dans le projet de thèmes thématiques Clean-Sky 2 U-HARWARD (www.u-harward-project.eu/), différentes solutions au niveau de l'avion permettant d'augmenter l'allongement des ailes sont étudiées pour réduire l'impact environnemental et améliorer les performances. Dans ce projet, l'ONERA et l'ISAE explorent les avantages potentiels et les éventuels pièges du concept SBW à travers une approche de conception multi-niveaux multidisciplinaire comprenant la conception globale de l'avion (OAD) et des études de conception disciplinaires affinées de l'aérodynamique et des aspects structurels clés du concept d’aile haubanée.L'article final présentera les modèles et outils mis en place pour effectuer l'exploration de conception multidisciplinaire à plusieurs niveaux du concept SBW au sein du projet U-HARWARD, ainsi que la conception intermédiaire obtenue.

Graphene, a single layer of carbon atoms tightly bound in a hexagonal honeycomb lattice to form a two-dimensional lattice, is a very interesting material with promising electronic, optical, chemical, and mechanical applicative potential [Geim and Novoselov, Nat. Mater. 6, 183 (2007)]. The properties of graphene make it suitable for a wide range of applications; however, its applicative future still depends on large scale technologies capable to robustly and reproducibly transfer its outstanding intrinsic properties into devices or complex structures. It must be recognized that a crucial technological problem, that still inhibits the applicability of high quality graphene material properties, is related to the patterning of this material using traditional top down instruments and lithographical methods. In this work, we will detail our investigations on applying a precise 30 keV Ga+ ion irradiation to selectively shape and modify a copper precursor surface for promoting the local growth of graphene surface domains. The morphology of these domains is investigated using scanning tunneling microscopy and spectroscopy to probe simultaneously the structural and the electronic properties at the atomic scale of the graphene films.

International audience; Multidisciplinary Design Optimization (MDO) methods aim at adapting numerical optimization techniques to the design of engineering systems involving multiple disciplines or components. Among MDO architectures, various ones are considering the resolution of the Multidisciplinary Design Analysis (MDA). In our study, the system of interest being an aircraft, the resolution of the MDA will be provided by the Future Aircraft Sizing Tool with Overall Aircraft Design (FAST-OAD), a point mass approach that estimates the required fuel and energy consumption for a given set of top-level aircraft requirements. In this context, a large number of mixed continuous, integer and categorical variables that arise from aircraft design has to be tackled by the optimization process. Recently, there has been a growing interest in mixed variables constrained Bayesian optimization based on Gaussian process surrogate models. In this setting, most existing approaches severely increase the dimension of the covariance matrix related to the surrogate. In fact, the construction of the Gaussian process model may not be scalable to practical applications involving a large number of mixed variables. In this paper, we address this issue by constructing a covariance kernel for the surrogate model that depends on only a few hyperparameters. The new kernel is constructed based on the information obtained from the partial least squares method. The obtained numerical results lead to interesting results for the optimization of a baseline aircraft and to reduce the fuel consumption of "DRAGON", a new hybrid electric propulsion aircraft, with a high number of mixed variables and for a small budget of time-consuming evaluations.

Background: We aimed to assess the effectiveness of two doses of mRNA COVID-19 vaccines against COVID-19 with the original virus and other lineages circulating in France. Methods: In this nationwide case-control study, cases were SARS-CoV-2 infected adults with onset of symptoms between 14 February and 3 May 2021. Controls were non-infected adults from a national representative panel matched to cases by age, sex, region, population density and calendar week. Participants completed an online questionnaire on recent activity-related exposures and vaccination history. Information about the infecting virus was based on a screening RT-PCR for either B.1.1.7 or B.1.351/P.1 variants. Findings: Included in our analysis were 7 288 adults infected with the original SARS-CoV-2 virus, 31 313 with the B.1.1.7 lineage, 2 550 with B.1.351/P1 lineages, and 3 644 controls. In multivariable analysis, the vaccine effectiveness (95% confidence interval) seven days after the second dose of mRNA vaccine was estimated at 88% (81-92), 86% (81-90) and 77% (63-86) against COVID-19 with the original virus, the B.1.1.7 lineage, and the B.1.351/P.1 lineages, respectively. Recent (2 to 6 months) history of virologically confirmed SARS-CoV-2 infection was found to be 83% (76-88), 88% (85-91) and 83% (71-90) protective against COVID-19 with the original virus, the B.1.1.7 lineage, and the B.1.351/P.1 lineages, respectively; and more distant (> 6 months) infections were 76% (54-87), 84% (75-90), and 74% (41-89) protective against COVID-19 with the original virus, the B.1.1.7 lineage, and the B.1.351/P.1 lineages, respectively. Interpretation: In real-life settings, two doses of mRNA vaccines proved to be effective against COVID-19 with the original virus, B.1.1.7 lineage and B.1.351/P.1 lineages. Funding: Institut Pasteur, Research & Action Emerging Infectious Diseases (REACTing), Fondation de France (Alliance “Tous unis contre le virus”).

Summary: Background: We aimed to assess the role of different setting and activities in acquiring SARS-CoV-2 infection. Methods: In this nationwide case-control study, cases were SARS-CoV-2 infected adults recruited between 27 October and 30 November 2020. Controls were individuals from the Ipsos market research database matched to cases by age, sex, region, population density and time period. Participants completed an online questionnaire on recent activity-related exposures. Findings: Among 3426 cases and 1713 controls, in multivariable analysis, we found an increased risk of infection associated with any additional person living in the household (adjusted-OR: 1•16; 95%CI: 1•11-1•21); having children attending day-care (aOR: 1•31; 95%CI: 1•02-1•62), kindergarten (aOR: 1•27; 95%CI: 1•09-1•45), middle school (aOR: 1•30; 95%CI: 1•15-1•47), or high school (aOR: 1•18; 95%CI: 1•05-1•34); with attending professional (aOR: 1•15; 95%CI: 1•04-1•26) or private gatherings (aOR: 1•57; 95%CI: 1•45-1•71); and with having frequented bars and restaurants (aOR: 1•95; 95%CI: 1•76-2•15), or having practiced indoor sports activities (aOR: 1•36; 95%CI: 1•15-1•62). We found no increase in risk associated with frequenting shops, cultural or religious gatherings, or with transportation, except for carpooling (aOR: 1•47; 95%CI: 1•28-1•69). Teleworking was associated with decreased risk of infection (aOR: 0•65; 95%CI: 0•56-0•75). Interpretation: Places and activities during which infection prevention and control measures may be difficult to fully enforce were those with increased risk of infection. Children attending day-care, kindergarten, middle and high schools, but not primary schools, were potential sources of infection for the household. Funding: Institut Pasteur, Research & Action Emerging Infectious Diseases (REACTing), Fondation de France (Alliance” Tous unis contre le virus”).

International audience; Manufacturing of microsystems based on complex three-dimensional microstructures requires critical steps such as mass calibrations and integration process. However, such steps involve several manipulation steps which are not well controlled thus the fragile 3D microstructures could be damaged or destroyed. In this work, we have demonstrated an AFM based direct mass measurement and manufacturing of 3D helical microswimmer. The proposed method shows to be rapid, repeatable and minimally-destructive thanks to the precise force control and manipulation by AFM. The proposed micromanipulation steps consist of the pick-measure-integrate manipulation steps using van der Waals force-based attachment and the mass measurement by resonant frequency shift. For the testing structures, we fabricated the 6 different types of 3D helical microswimmers vertically fabricated on the conical shape microneedle supports for uniform surface metallization and facile detachment. With the mass measurement sensitivity of 25 Hz/pg and the direct integration to microfluidics, we successfully demonstrated the 3D propulsion and non-contact micromanipulation by 3D helical microswimmer in microfluidics.

Funding Acknowledgements Type of funding sources: None. Introduction Aortic Stenosis (AS) is a common condition in patients over 75 years. Latest ESC recommendations differentiate 4 types of AS according to: Indexed Stroke Volume (SVi), mean gradient and left ventricular ejection fraction (LVEF). The aim of our study is to evaluate prognosis of patients who have had a transcatheter aortic valve replacement (TAVR), in terms of mortality, according to the 4 types of AS. Methods This study compares prognosis of 620 patients who had TAVR between January 1, 2015 and December 31, 2018. Patients were classified into 4 groups according to AS type: high gradient; low gradient, low flow, low LVEF; low gradient, low flow, normal LVEF; low gradient, normal flow. Results 69 patients (11.1%) died within 12 months of the procedure: 49 in the high gradient group (9.4%); 13 in the low gradient, low flow, low LVEF group (47.1%); 1 in the low gradient, low flow, normal LVEF group (5%); 6 in the low gradient, normal flow, normal LVEF group (18.2%). All-cause mortality at one year follow-up is higher in low-gradient, low-flow, altered LVEF group (p = 0.0004) than in other groups. Patients in this group were significantly more often admitted for heart failure than patients in high-gradient group (p = 0.009). Conclusion A complete echocardiography evaluation is needed to evaluate AS, its severity and type. Patients in the low gradient, low flow, low LVEF group have an independent risk of mortality at 12 months higher than other groups and are more hospitalized than patients in the high gradient group.

International audience; Mass measurements of complex three-dimensional microstructures are essential to the design and development of microsystems. However, the mass measurements of such microstructures require several manipulation steps which are not well controlled. We have demonstrated a rapid, reliable and lessdestructive on-chip mass measurement method by incorporating with AFM micromanipulation. It is based on AFM pick-measureplace micromanipulation using Van der Waals attraction and the mass measurement by resonant frequency shift. The measurement sensitivity revealed to be 25 Hz/pg and it could be promising to characterize MEMS with complex geometries and composite materials.

Based on discussions in a workshop associated with the conference The Agroecological Imagination: A Franco-American Exchange, we synthesize the state of agroecological education. We focus on three ...

Cacao agroforestry systems (CAFS) can provide supporting services such as optimum light conditions for cacao growth, water and nutrient cycling and regulating services such as pest and disease control and climate regulation. This review considers recent literature on the manifestation of these services in CAFS around the world to provide an overview of scientific knowledge. Crown structures of associated trees can facilitate optimum light conditions for cacao growth, and provide water through vertical root segregation. Leaf litter fall and roots from associated species contribute to nutrient cycling. Both nitrogen-fixing and non-nitrogen-fixing species can provide nutrients to the cacao plant, though competition from certain species may limit phosphorus and potassium uptake. Pest and disease regulating services can arise through careful shade management to create a microclimate which reduces susceptibility of cacao to fungal diseases and sun-loving pests. All CAFS store carbon to varying degrees; those resembling original forest much more than simple two-species systems from which shade trees are removed after maturity of the cacao stand. CAFS also promotes biodiversity conservation depending on structure, management, and landscape arrangement, though not to the extent of natural forests. Research opportunities to increase provision of these services include optimal spatial arrangement for nutrient cycling and functional diversity as well as landscape connectivity for biodiversity conservation. Trade-offs between carbon storage, biodiversity, cacao yield and socio-economic resilience are presented, indicating that optimization of ecosystem services in CAFS requires consideration of interactions between all services, including socio-cultural and economic ones.

Perennial grain crops are currently being developed, yet little is known about farmer interest in these new crops. We conducted an online survey in France and the United States to evaluate interest in perennial grains. Results show that 57% of the farmers who responded reported they were &ldquo, interested&rdquo, or &ldquo, very interested&rdquo, in growing perennial grains, whereas 41% reported they needed more information. Respondents consistently ranked &ldquo, to increase or maintain farm profitability&rdquo, and &ldquo, to improve soil health&rdquo, among the top reasons why they were interested in growing perennial grains. Reasons why farmers were interested, as well as their concerns about growing perennial grains, differed by country and farm type (i.e., conventional vs. organic). More farmers in France than in the United States ranked &ldquo, to reduce labor requirements&rdquo, and more conventional farmers than organic farmers ranked &ldquo, to reduce inputs&rdquo, among their top reasons for their interest. Farmers were also asked about integration strategies and management. More farmers in the United States than in France and more conventional farmers than organic farmers reported that they were interested in dual-purpose perennial crops that can be harvested for both grain and forage. Results from this survey can guide future perennial grain research and development.

Ce livre posthume du philosophe Etienne Tassin s’inscrit dans le sillage du Tresor perdu et du Monde commun. Apres la parution de ce dernier en 2003, l’auteur avait le projet d’ecrire un livre sur l’action ou il prolongerait et approfondirait le questionnement engage. Ensuite, d’autres projets l’ont requis, mais sans que celui-la ne cesse de le hanter. Aussi traverse-t-il les treize chapitres de cet ouvrage constitue de reecritures (inedites ou non) de conferences issues du travail theorique ...

International audience; Intermediate wheatgrass (Thinopyrum intermedium (Host) Barkworth & D.R. Dewey) is being developed for use as a new perennial grain crop through breeding and agronomic research. However, progress has been hampered by lack of understanding of environmental requirements for flowering and grain production. Therefore, we developed a phenology model for IWG adapted from the STICS soil-crop model. The model was compliant with experimental results (relative root mean square error = 0.03). The optimal vernalizing temperature was between 4 and 5 • C, optimal daylength between 13 and 14h, while daylength below 11h slowed reproductive development. Vernalization requirement was found to be a constraining inductive process. Including a photoperiod limitation to the model with temperature improved its ability to predict induction at various latitudes. Therefore, timing and duration of vegetative vs. reproductive growth may differ between environments and change reproductive tiller elongation earliness, weed competitiveness, management timing, and stress conditions during phases critical to grain yield. Accurate phenology models will enable optimal field management and inform future breeding strategies. However, plasticity may lead to divergent ideotypes under various agroecosystems.

Resume Objectifs Diminuer l’irradiation des patients lors des gestes de rhumatologie interventionnelle, sans diminuer la qualite du geste. Methodes La dose d’irradiation recue (produit dose surface [PDS]) a d’abord ete quantifiee lors de 283 infiltrations realisees sous scopie, avant optimisation, entre mai et juillet 2013. Elle a ete a nouveau mesuree en 2014, lors de 158 nouvelles infiltrations realisees cette fois apres optimisation des procedures : (1) interposition d’un filtre cuivre ; (2) retrait de la grille antidiffusante ; (3) reglage de la sensibilite de la cellule d’exposition en mode eleve. Resultats Avant optimisation, l’irradiation moyenne etait de 175 μgray/m 2 pour les infiltrations de quatre articulations zygapophysaires et de 43 μgray/m 2 pour celles des hanches, mais elle restait inferieure a 20 μgray/m 2 pour celles des epaules (15,7), chevilles (7,7), poignets (3,7) et doigts (3,3). Une tres nette diminution des PDS a ete observee pour chaque site d’infiltration apres optimisation des procedures, la baisse de la PDS allant de 52 % (pour l’epaule) a 87 % (pour les articulations zygapophysaires, desormais a 22,7 μgray/m 2 seulement). Ceci etant vrai pour les 3 etapes : installation du patient, geste medical et cliche final. Les PDS des infiltrations des articulations zygapophysaires etaient de 84 (54,5–108,5) μgray/m 2 pour les indices de masse corporelle (IMC) 2 pour les IMC > 30. Conclusion Des procedures techniques simples permettent une diminution majeure de l’irradiation des patients lors des infiltrations realisees sous scopie, en particulier pour les articulations zygapophysaires et chez des personnes a IMC eleve.

The paper presents the measured cumulative yields of 44 Ti for nat Cr, 56 Fe, nat Ni and 93 Nb samples irradiated by protons at the energy range 0.04–2.6 GeV. The obtained excitation functions are compared with calculations of the well-known codes: ISABEL, Bertini, INCL4.2+ABLA, INCL4.5+ABLA07, PHITS, CASCADE07 and CEM03.02. The predictive power of these codes regarding the studied nuclides is analyzed.

Nitrogen (N) deficiency and weed infestation are main factors limiting yield and yield stability in organic wheat. Organic fertilizers may be used to improve crop performance but off-farm input costs tend to limit profitability. Instead, forage legumes may be inserted into the crop rotation to improve the N balance and to control weed infestation. In opposition to simultaneous cropping, relay intercropping of legumes in organic winter wheat limits resource competition for the legume cover crop, without decreasing the performance of the associated wheat. The aim of this study is to evaluate the effect of spring organic fertilization on the performance of intercropped legumes and wheat, and on services provided by the legume cover. Two species of forage legumes ( Trifolium pratense L . and Trifolium repens L . ) were undersown in winter wheat ( Triticum aestivum L. cv Lona) in five organic fields during two consecutive crop seasons. Organic fertilizer was composed of feather meal and applied on wheat at legume sowing. The cover crop was maintained after the wheat harvest and destroyed just before sowing maize. Spring organic nitrogen fertilization increased wheat biomass (+35%), nitrogen (+49%), grain yield (+40%) and protein content (+7%) whatever the intercropping treatment. At wheat harvest, red clover biomass was significantly higher than white clover one (1.4 vs. 0.7 t ha −1 ). Nitrogen fertilization decreased forage legume above-ground biomass at wheat harvest, at approximately 0.5 t ha −1 whatever the specie. No significant difference in forage legume biomass production was observed at cover killing. Nitrogen accumulation in legume above-ground tissues was significantly higher for white clover than for red clover. Both red and white clover species significantly decreased weed infestation at this date. Nitrogen fertilization significantly increased weed biomass whatever the intercropping treatment and decreased nitrogen accumulation in both clover species (−12%). We demonstrated that nitrogen fertilization increased yield of wheat intercropped with forage legume while the performance of legumes was decreased. Legume growth was modified by spring fertilization whatever the species.

To face the increasing environmental footprint of commercial aviation, industrial and research efforts have been focusing on exploring unconventional configurations and new propulsion paradigms, mostly based on electric technology. Such explorations require Overall Aircraft Design that has to be performed in an integrated multidisciplinary design environment. Such design environments are often limited to multidisciplinary analysis, adapted for a single aircraft configuration or require an important effort to be mastered. FAST-OAD is a software program developed by ONERA and ISAE-SUPAERO for aircraft sizing analysis and optimization that aims at user friendliness and modularity. It is an aircraft sizing code based on multidisciplinary design optimization techniques and the point mass approach to estimate the required fuel and energy consumption for a given set of TLARs. This paper presents the motivations for moving from the original software program, called FAST, to the open source code FAST-OAD based on OpenMDAO.

International audience; Sustainable cropping systems that balance agricultural productivity and ecological integrity are urgently needed. Overreliance on soil tillage and herbicides to manage weeds has resulted in a number of major environmental problems including soil erosion and degradation, biodiversity loss, and water quality impairment. Combining organic farming and conservation agriculture is a viable alternative to address these challenges. In particular, mulch-based no tillage systems can be used to reduce tillage in organic production, improving soil quality while decreasing labor and fuel requirements. This technique involves planting cash crops directly into terminated cover crops that remain on soil surface and serve as mulch to prevent weeds establishment and protect soil from erosion. Despite potential benefits, adoption of organic mulch-based no tillage is limited due to challenges with cover crop termination, weed suppression, and yields. Here, we (i) review international research on organic mulch-based no tillage systems (soybean and maize), (ii) identify production issues that limit the success of this technique, and (iii) outline research priorities. As result, organic mulch-based no tillage is knowledge intensive and requires advanced planning and careful management of the cover crop. Primary challenges include timely cover crop establishment and termination, nutrient management, reduced soil temperature and moisture at planting, and achieving adequate seed-to-soil contact when planting into thick mulch on soil surface. Long-term research is needed to better understand the effects of this technique production on soil health and on the broader environmental and economic impacts. To increase adoption of organic mulch-based no tillage, future research should focus on (i) screening species and cultivars to identify cover crop and crop combinations that optimize cropping system performance and (ii) developing equipment for improving cover crop termination and seed placement. Research conducted in partnership with farmers will be valuable for developing guidelines and increasing adoption of this technique.