La singularité de l'entrepreneuriat des migrants en France

International audienceS'intéressant aux entrepreneurs migrants en France et plus spécifiquement dans ce travail, aux publics originaires d'Afrique, cet article interpelle la singularité de l'entrepreneuriat des migrants. Dans quelle mesure ce dernier se distingue-t-il de l'entrepreneuriat au pays et de l'entrepreneuriat autochtone ? Ces questions posent instantanément la question de l'acculturation de l'entrepreneur migrant. Comment arbitre-t-il entre deux modèles culturels qui supportent des formes d'entrepreneuriat différentes ? La présente contribution, à vocation exploratoire, s'appuyant sur quelques études de cas et sur de l'ethno-observation réalisée au sein d'une structure d'accompagnement dont est membre l'un des auteurs, confronte la littérature et le terrain et énonce une liste de premières propositions répondant à ces questions

Rapic project: toward a new generation of inexpensive heat exchanger-reactors for process intensification

Process intensification (PI) in chemical production is a major concern of chemical manufacturers. This alternative technology involves transposing syntheses into continuous plug flow reactors with process intensification, leading to a multifunctional heat exchanger-reactor. In this context, the RAPIC R&D project aims to develop an innovative low-cost component (in the 10 kg/hour range). This project deals with the design from the local to the global scale and with testing, from elementary mock-ups to pilot scale. The present paper gives a detailed description of this research project and presents the main results on specification and definition of the reaction channel and the first simple mock-ups

L’application de la DCE dans les départements et régions d’outre-mer : la mise en lumière des discordances entre le concevable et le possible à la Martinique

Dans un contexte de changements environnementaux globaux, la question de la gestion de l’eau est d’autant plus exacerbée dans les départements et régions d’outre-mer français (Drom). Les savoirs incertains relatifs au contexte de changement global sont en contradiction avec le concept de « conditions de référence » mis en œuvre par la directive cadre européenne sur l’eau (DCE). Les contextes, où incertitude et risque s’entremêlent, autorisent l’hypothèse d’une probable discordance entre des injonctions prévues par la DCE et les possibilités de gestion autorisées par les situations locales. L’objectif de cette contribution est d’interroger les situations Dromiennes sur leur capacité à répondre aux injonctions de la DCE. Si l’application de la DCE dans les Drom a effectivement été porteuse d’efforts soutenus dans la concertation territoriale et l’acquisition de connaissances scientifiques, l’insuffisance de données scientifiques historiques ne permet pas de définir des « conditions de référence » selon une conception métastable de l’équilibre des écosystèmes. L’exemple de la Martinique illustre les difficultés que rencontrent les Drom à donner sens au concept de « conditions de référence » difficilement définissable à cause d’incertitudes dans les savoirs technico-scientifiques. Au delà de cette question, l’inertie autour de la mise en œuvre d’actions concrètes est d’autant plus exacerbée dans ces territoires. Les situations conjoncturelles où incertitude des savoirs, risque et principe de précaution s’entremêlent, sont favorable à accroître les durées de mise en œuvre de l’action collective. Les organisations compétentes sur la gestion des milieux aquatiques dans les Drom gagneraient à investir les instruments financiers qui dynamiseraient la préservation et l’amélioration de l’état écologique des systèmes aquatiques, à partir de « conditions de référence » notamment instituées selon les valeurs socio-écologiques des systèmes aquatiques.In a context of global environmental change, the issue of water management is aggravated in the French overseas departments. Uncertain knowledge on the context of global change is in contradiction with the concept of “reference conditions” implemented by the European Water Framework Directive (WFD). This context, where uncertainty and risk are intertwined, raises the hypothesis of a possible discrepancy between the obligations set by the WFD and the management options permitted by local conditions. The objective of this paper is to examine the situation in Overseas Departments and their ability to meet the requirements of the WFD. If the implementation of the WFD in the Overseas Departments was followed by major efforts in local consultation and the acquisition of scientific knowledge, the lack of historical scientific data prevents the determination of “reference conditions” as a metastable conception of the ecosystems’ balance. The case of Martinique illustrates the challenges faced by Overseas Departments to ascertain the concept of “reference conditions”, which is difficult to define due to uncertainties of the technical and scientific knowledge. Beyond this issue, the inertia around the implementation of concrete actions is exacerbated in those territories. Cyclical conditions, where uncertainty of knowledge, risk and the precautionary principle interlace, are prone to increase the duration of implementation of collective actions. Relevant institutions in the management of aquatic environments in the Overseas Departments would benefit from using financial instruments that could boost the preservation and improvement of the ecological status of aquatic systems from “reference conditions” defined by the socio-ecological values of the aquatic systems

CHA2DS2-VASc Score for Predicting Stroke and Thromboembolism in Patients With AF and Biological Valve Prosthesis

International audienc

Compliance with Gluten Free Diet Is Associated with Better Quality of Life in Celiac Disease

The quality of life (QOL) of patients with celiac disease (CD) can be altered by both symptoms of the disease and by the restrictions of the gluten-free diet (GFD). The objective was to determine the factors associated with better QOL in a large cohort of CD patients. A link to an online survey was sent to the members of the French Association of Gluten Intolerant People (AFDIAG). The French-Celiac Disease Questionnaire (F-CDQ), scoring from 0 to 100, was used to measure the QOL. Other data collected were sociodemographic characteristics, information on CD, purchasing and consumption habits of gluten-free products, and a self-assessment scale (ranging from 0 to 10) to determine the compliance with the GFD. Among the 907 CD patients who returned the questionnaire, 787 were analyzed (638 women (81%); median age: 49 years; 71% with self-assessed GFD compliance > 8). Their median F-CDQ was 73 (range: 59-82). In multivariate analysis, the main factors associated with a better quality of life were the long duration of the GFD, good compliance with the GFD, and the number of follow-up visits. Compliance with and duration of the GFD are associated with a better quality of life in patients with CD. Taking this into consideration would offset its restrictive aspect and improve its adherence

Cyclic Hypervalent Iodine Reagents for Azidation: Safer Reagents and Photoredox-Catalyzed Ring Expansion

Azides are building blocks of increasing importance in synthetic chemistry, chemical biology, and materials science. Azidobenziodoxolone (ABX, Zhdankin reagent) is a valuable azide source, but its safety profile has not been thoroughly established. Herein, we report a safety study of ABX, which shows its hazardous nature. We introduce two derivatives, tBu-ABX and ABZ (azidobenziodazolone), with a better safety profile, and use them in established photoredox- and metal-mediated azidations, and in a new ring-expansion of silylated cyclobutanols to give azidated cyclopentanones

Pancreatic islet cells isolation and transplantation into the bone marrow

Bone marrow is currently being considered as an alternative site for pancreatic islet transplantation. The goal of the present review is to report preclinical and clinical studies taking advantage of this new implantation site. Preclinical studies in mice demonstrated that syngeneic islets could survive in bone marrow indefinitely with a higher success in providing euglycemia compared to islets transplanted into the traditionally used implantation site, namely, the liver. In concordant and discordant xenogeneic models, the immune response was more stringent when islets were transplanted to the bone marrow as compared to the traditional implantation site in rodents, the kidney capsule. As demonstrated by histology, cellular and humoral rejection was prevented by islets protected by micro-encapsulation in calcium-alginate beads, and a similar degree of fibrotic reaction was induced at both site, although functional studies in diabetic animals are still needed. In clinical settings, a pilot study of four patients who received islet auto-transplantation into the bone marrow after a total pancreatectomy had been showed to be safe and feasible. Three out of four patients had a functioning graft, as measured by serum C-peptide, at an average follow-up of 545 ± 369 days. In conclusion, islet transplantation into the bone marrow may be a viable alternative to the liver as an implantation site, particularly with the perspective of transplanting encapsulated xenogeneic islets. Meanwhile, the efficacy of immunosuppressive drugs would still require to be evaluated in allogeneic and xenogeneic preclinical models of islet transplantation into the bone marrow

Antibody-induced erythrophagocyte reprogramming of Kupffer cells prevents anti-CD40 cancer immunotherapy-associated liver toxicity

BackgroundAgonistic anti-CD40 monoclonal antibodies (mAbs) have emerged as promising immunotherapeutic compounds with impressive antitumor effects in mouse models. However, preclinical and clinical studies faced dose-limiting toxicities mediated by necroinflammatory liver disease. An effective prophylactic treatment for liver immune-related adverse events that does not suppress specific antitumor immunity remains to be found.MethodsWe used different mouse models and time-resolved single-cell RNA-sequencing to characterize the pathogenesis of anti-CD40 mAb induced liver toxicity. Subsequently, we developed an antibody-based treatment protocol to selectively target red blood cells (RBCs) for erythrophagocytosis in the liver, inducing an anti-inflammatory liver macrophage reprogramming.ResultsWe discovered that CD40 signaling in Clec4f$^{+}$Kupffer cells is the non-redundant trigger of anti-CD40 mAb-induced liver toxicity. Taking advantage of the highly specific functionality of liver macrophages to clear antibody-tagged RBCs from the blood, we hypothesized that controlled erythrophagocytosis and the linked anti-inflammatory signaling by the endogenous metabolite heme could be exploited to reprogram liver macrophages selectively. Repeated low-dose administration of a recombinant murine Ter119 antibody directed RBCs for selective phagocytosis in the liver and skewed the phenotype of liver macrophages into a Hmox$^{high}$/Marco$^{high}$/MHCII$^{low}$anti-inflammatory phenotype. This unique mode of action prevented necroinflammatory liver disease following high-dose administration of anti-CD40 mAbs. In contrast, extrahepatic inflammation, antigen-specific immunity, and antitumor activity remained unaffected in Ter119 treated animals.ConclusionsOur study offers a targeted approach to uncouple CD40-augmented antitumor immunity in peripheral tissues from harmful inflammatoxicity in the liver

Discrimination of Musa banana genomic and sub-genomic groups based on multi-elemental fingerprints and chemometrics

The potential of unripe banana flour multi-elemental fingerprints for classifying banana genomic and subgenomic groups was assessed using chemometrics. The elemental concentration of N, P, K, Mg, Ca, Zn, Cu, Mn, Fe, and B in unripe banana flour from 33 banana varieties belonging to four genome groups and 11 subgenome groups were determined using Flame-atomic Absorption spectrometry and colorimetry. Principal component analysis (PCA) combined with linear discriminant analysis (LDA), support vector machine (SVM), and artificial neural network (ANN) was applied for classification with an 80:20 split between the calibration and verification sets (157 and 39 samples, respectively). The elements K, N, and Mg presented the highest mean concentrations of 1273 mg/100 g, 424 mg/100 g, and 132 mg/100 g, respectively. The classification model verification set samples were successfully classified based on their genome groups (100 % accuracy) and subgenome groups (78.95–100% accuracy) for PCA-LDA, PCA-ANN, and PCA-SVM models. The results demonstrate that multi-elemental fingerprinting combined with chemometrics can be employed as an effective and feasible method for classification of Musa genomic and sub-genomic groups