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An effective hybrid meta-heuristic method for the simultaneous batch production and transportation problem in additive manufacturing
No full textInternational audienceOne notable advancement in additive manufacturing (AM) is the mobile mini-factory, which uses a truck equipped with an AM machine to produce orders while en-route to customers' locations. This offers potential benefits such as reduced delivery times and storage expenses for companies. This study investigates a simultaneous batch production and transportation problem (denoted by SBPTP) in additive manufacturing. To solve this problem, a mixed integer linear programming (MILP) model is first formulated. Then, to solve large-scale problems, a meta-heuristic method (denoted by SA-CP) combining a simulated annealing (SA) algorithm, an ant colony optimisation algorithm (ACO) and a cutting-plane algorithm is developed, in which the assignment subproblem is dealt with the SA, the simultaneous production and transportation subproblem is dealt with the ACO, and finally the current solution is further improved by the cutting-plane algorithm. Computational experiments are conducted on both randomly generated instances and modified benchmark instances. The results demonstrate that the SA-CP is very effective since it can obtain the solutions with an average relative percentage gap 0.16% on randomly generated instances and −0.09% on modified benchmark instances within less than 180 CPU seconds, compared to those obtained by solving the MILP model directly with CPLEX within 1 h
Call for preserving specialized knowledge and contributions of the CAT to advancing ATMPs in Europe
No full textInternational audienc
Subunit 3 of the SUPERKILLER complex mediates microRNA172-directed cleavage of Nodule Number Control 1 in Medicago truncatula
No full textInternational audienceAbstract Legumes and rhizobia establish a nitrogen-fixing symbiosis that involves the formation of a lateral root organ, the nodule, and the infection process that allows intracellular accommodation of rhizobia within nodule cells. This process involves substantial gene expression changes regulated at the transcriptional and post-transcriptional levels. We have previously shown that a transcript encoding subunit 3 of the SUPERKILLER Complex (SKI), which guides mRNAs to the exosome for 3´-to-5´ degradation, is required for nodule formation and bacterial persistence within the nodule, as well as the induction of early nodulation genes, including early nodulin40 (MtENOD40), during the Medicago truncatula–Sinorhizobium meliloti symbiosis. Here, we reveal through transcript degradome and small RNA sequencing analysis that knockdown of MtSKI3 impairs the miR172-directed endonucleolytic cleavage of the mRNA encoding Nodule Number Control 1 (MtNNC1), an APETALA2 transcription factor that negatively modulates nodulation. Knockdown of MtNNC1 enhances nodule number, bacterial infection, and the induction of MtENOD40 upon inoculation with S. meliloti, whereas overexpression of an miR172-resistant form of MtNNC1 significantly reduces nodule formation. This work identifies miR172 cleavage of MtNNC1 and its control by MtSKI3, a component of the 3´-to-5´mRNA degradation pathway, as a regulatory hub controlling indeterminate nodulation
“Write your model almost as you would on paper and Michel will take care of the rest!” Michel Juillard’s contribution to macroeconomics in historical perspective
No full textInternational audienceIn this article, we document Michel Juillard’s contribution to macroeconomics. Best known as the creator of the computer package Dynare, Juillard’s impact extends far beyond software development. We trace his training and career from his first encounter with computers in high school through his ongoing work on Dynare. His contribution to macroeconomics, we argue, is threefold: intellectual (devising algorithms and addressing specific computational problems for a class of models), technical (writing code and developing a computer package), and institutional (establishing and maintaining the governance structures that ensure Dynare’s sustainability as a digital commons). Juillard’s career highlights broader questions about adapting Ostrom’s framework to digital commons development, the principles that govern software development, and the place computational economics should occupy in the history of macroeconomics
Psychological foundations of fast fashion: managing tensions and paradoxes, and navigating ethical dualities
No full textInternational audienceThe fashion industry has come under intense scrutiny for its environmental and ethical challenges. While some argue that fast fashion democratizes style by making it accessible to a broader set of consumers, others question its legitimacy. This study adopts a centrist perspective, acknowledging both the difficulty and the necessity of balancing business imperatives with ethical exigencies. Drawing on the dual organizational ontologies lens, the study positions fast fashion businesses as both internal markets and communities, identifying the resultant tensions, paradoxes, and ethical dualities. To examine these dynamics, the study applied Media Discourse Analysis (MDA) in combination with Gioia's approach to analyse popular media articles, online videos, and company annual reports/webpages of fast fashion businesses. The analysis delineated four ethical dualities: financial sustainability and environmental sustainability, internal and external stakeholder well-being, business priorities and corporate responsibilities, and feel good and greater good. These dualities are underpinned by five underlying tensions and paradoxes: business viability versus environmental degradation, customer value versus business model, industry dynamics versus working conditions, business practices versus legal and ethical responsibilities, and sustainability mandates versus ground realities. Building on these findings, the study proposes twelve strategic pathways for managing the tensions and paradoxes and navigating the dualities. In sum, the study findings advance theoretical understanding of the ethical dualities and contribute practical insights for reconciling the ethical contradictions inherent in the market-based and the community-based views of fast fashion businesses
Technologies, cultures et sociétés. Une approche socio-philosophique
No full textInternational audienc
Réglementer l'exploitation animale, surveiller les travailleurs, nourrir la Nation : une histoire de l'idéologie capitaliste française depuis les abattoirs (La Villette, XIXe - XXe siècles)
No full textInternational audienc
Will You Follow Your Job to the Suburbs? Commuting, Locational Amenities and Wages in a Large Metro Area
No full textWe examine how relocations from the center to the suburbs of establishments employing mainly skilled workers affect the composition and wages of their employees. Using data from the Paris metro area, we find that these relocations increase average commuting time by 19%. In response, firms compensate highly paid workers with 10 to 20% of their hourly wage per additional hour of commuting. Lower-paid workers receive no compensation and are more likely to leave. Consistent with workers valuing locational amenities, we find little increase in separation and no wage adjustment for increased commuting time when establishments relocate to more attractive neighborhoods
Unexpected diversity and ecological significance of uncultivable large virus-like particles in aquatic environments
No full textInternational audienceThe discovery of jumbo phages and giant viruses of microeukaryotes has transformed our perception of the virosphere. Metagenomic and metatranscriptomic data further highlight their diversity and ecological impact. Nevertheless, sequence-based approaches fail to take into account the morphological diversity of non-cultivated viruses, resulting in our fragmented understanding of their nature and role in the environment. Here, we combined flow cytometry and electron microscopy to uncover both previously unsuspected morphological diversity and significant abundances of large virus-like particles in aquatic environments. We discovered new viral morphotypes, all likely to be associated with microeukaryotes. We also obtained insights into the multi-year dynamics of the abundances of both giant microeukaryotic virus-like particles and jumbo phage-like particles. This work deepens our understanding of large virus and reveals their key role as regulators of microbial communities
Caractérisation de l'effet bénéfique d'Enterobacter sp. SA187 sur Arabidopsis thaliana en condition de CO₂ élevé ou de faible azote
No full textModern agriculture must address the dual challenge of reducing reliance on synthetic nitrogen (N) fertilizers and adapting to rising atmospheric CO₂ levels. Although elevated CO₂ (eCO₂) can initially stimulate plant growth, its long-term benefits are often limited by nutrient imbalances, particularly reduced tissue N. Simultaneously, soil N limitation remains a major constraint on agricultural productivity, and the use of synthetic N-fertilizers is both costly and environmentally detrimental. My thesis investigates the interaction between the endophytic bacterium Enterobacter sp. SA187 and the model plant Arabidopsis thaliana under two interrelated and globally relevant scenarios: low nitrate and eCO₂. Using a combination of physiological, molecular, genetic and omics approaches, it was demonstrated that SA187 promoted plant growth under both scenarios. Under eCO₂, SA187 alleviated typical eCO₂-induced N dilution by restoring the C:N balance and promoting both root and shoot growth. Transcriptomic and metabolomic analyses revealed that SA187 activated pathways related to primary metabolism, N assimilation, and hormones including ethylene, jasmonic acid, and salicylic acid. The growth-promoting effects of SA187 were abolished in the ethylene-insensitive mutant ein2-1, confirming the critical role of ethylene signaling in mediating this beneficial interaction. Under low nitrate conditions, SA187 significantly enhanced growth, root architecture, and shoot N content. These benefits were tightly associated with improved nitrate uptake and N allocation to shoots, mediated by a coordinated regulation of high-affinity nitrate transporters (HATS), particularly NRT2.5, NRT2.6, and ethylene signaling. Notably, SA187-induced expression of NRT2.5 was dependent on ethylene signaling, whereas NRT2.6 regulation appeared partially independent. Together, SA187 was identified as a multifunctional microbial partner capable of enhancing plant performance under both nutrient-limited and climate-altered conditions. These findings offer new mechanistic insights into plant–microbe interactions and highlight the potential of microbial-based approaches to sustain plant productivity in a low-input, climate-resilient agriculture.L’agriculture moderne doit relever le double défi de réduire sa dépendance aux engrais azotés de synthèse et de s’adapter à l’augmentation de la concentration atmosphérique en CO₂. Bien que l’élévation du CO₂ (eCO₂) puisse stimuler la croissance des plantes dans un premier temps, ses effets bénéfiques à long terme sont souvent limités par des déséquilibres nutritionnels, notamment une diminution de la teneur en azote (N) dans les tissus. Par ailleurs, la limitation en N dans les sols reste un obstacle majeur à la productivité agricole, tandis que l’usage d’engrais azotés de synthèse demeure couteux et préjudiciable à l’environnement. Cette thèse explore l’interaction entre la bactérie endophyte Enterobacter sp. SA187 et la plante modèle Arabidopsis thaliana dans deux contextes interconnectés et d’importance mondiale : la faible disponibilité en nitrate et une concentration élevée en CO₂. À l’aide d’approches physiologiques, moléculaires, génétiques et omiques, il a été démontré que SA187 stimule la croissance des plantes dans ces deux conditions. En condition de CO₂ élevé, SA187 compense la dilution azotée typiquement observée, en restaurant l’équilibre C:N et en favorisant la croissance des racines et des parties aériennes. Les analyses transcriptomiques et métabolomiques montrent que SA187 active des voies liées au métabolisme primaire, à l’assimilation de l’azote et aux hormones telles que l’éthylène, l’acide jasmonique et l’acide salicylique. Les effets bénéfiques de SA187 sur la croissance disparaissent chez le mutant ein2-1 insensible à l’éthylène, confirmant le rôle central de cette voie dans l’interaction positive. En situation de faible disponibilité en nitrate, SA187 améliore significativement la croissance, l’architecture racinaire et la teneur en N des parties aériennes. Ces bénéfices sont étroitement liés à une meilleure absorption du nitrate et à son allocation vers les tissus aériens, via une régulation coordonnée des transporteurs à haute affinité (HATS), notamment NRT2.5, NRT2.6, ainsi que la signalisation de l’éthylène. Il est à noter que l’expression induite de NRT2.5 par SA187 dépend de la signalisation éthylène, tandis que celle de NRT2.6 semble partiellement indépendante. Ainsi, SA187 est identifié comme un partenaire microbien multifonctionnel, capable d’améliorer les performances des plantes en conditions de stress nutritionnel et climatique. Ces résultats apportent de nouvelles connaissances mécanistiques sur les interactions plante–microbe et soulignent le potentiel des approches microbiennes pour maintenir la productivité des cultures dans une agriculture durable, à faibles intrants et résiliente face au changement climatique