Coproduire les services publics: Gouvernance palliative des inondations et citoyenneté en milieu périurbain à Pikine (Sénégal)

The recurring floods experienced in recent years by many urban centres in West Africa are not merely the consequence of global climate change. Large parts of the poor urban populations in West Africa often live in hazardous areas where urban planning is inadequate and where the public services, infrastructure and protective regulations that are needed in order to face flood issues are poorly provided. As a result, recurrent flooding reinforces existing social inequalities and the vulnerability of the urban poor. This does, however, not mean that the delivery of collective services related to flood response does not exist or that it is ungoverned. In order to cope with inefficient public service provision, the inhabitants often organize to ensure that flooding is addressed. This study shows that in Pikine, a city located at the outskirts of Dakar (Senegal), the governance of floods entails the daily coproduction of flood prevention and adaptation services, where users play an important and active role. The authors show that this ‘palliative governance’ has a direct impact on vulnerable populations’ capacity to cope with and adapt to recurrent flooding. The authors show that the informality that is essential to the coproduction of services should not be seen as an opposition to the State, but rather as essential to the daily functioning of the state, as well as a manifestation of ordinary citizenship by residents of deprived neighbourhoods.  Les dégâts causés par les fortes inondations qu’ont connues de nombreux centres urbains en Afrique de l’Ouest ces dernières années ne sont pas le seul fait des changements climatiques globaux, mais la résultante de facteurs structurels locaux tels qu’une urbanisation anarchique, le manque d’infrastructure et l’insuffisance des services de base, qui rendent particulièrement vulnérables les populations urbaines pauvres. Ces inondations tendent à renforcer les inégalités sociales et la vulnérabilité des plus pauvres face aux changements climatiques. Pour pallier au désengagement marqué de l’État et des municipalités en matière de services publics, les populations concernées s’organisent pour assurer la provision des services d’atténuation des inondations. Les auteurs de cet article montrent qu’à Pikine (dans la banlieue de Dakar, Sénégal) la gouvernance des inondations au quotidien se traduit par une coproduction des services dans laquelle les usagers jouent un rôle actif important. Cette « gouvernance palliative » a des répercussions directes sur la capacité d’adaptation et de prévention des risques liés aux changements climatiques des populations vulnérables. Les auteurs avancent que les initiatives locales et « l’informalisation » qui caractérisent la coproduction de ces services ne constituent pas une opposition à l’État, mais une mesure indispensable de son fonctionnement au quotidien et une manifestation de la citoyenneté ordinaire des habitants des quartiers urbains défavorisés. &nbsp

The real governance of disaster risk management in peri-urban Senegal: Delivering flood response services through co-production

Disastrous and recurring floods have impacted West African urban centres over the last decade, accentuating already existing vulnerabilities in poor neighbourhoods. Climate change-induced changing weather patterns and more extreme weather events are only part of the explanation for this situation, as large segments of the urban population in West Africa are not offered the public services, infrastructure and protective regulations needed in order to respond to floods. Through an empirically grounded approach, the article shows that the ability to respond to floods is formed largely outside the realm of the state in a poor peri-urban municipality of Pikine, Dakar. The authors show how the organization of collective services pertaining to flood response and climate change adaptation is maintained through co-production among service users and providers entailing a mixture of diverse governance modes. The article concludes that weak state capacity is not equivalent to non-existent or ungoverned collective services linked to floods. While flood response service delivery through co-production may constitute the best available options in a context of poor resources, because of the negotiated character of public service delivery, it also creates an environment favourable for brokers to take ownership of central processes of service delivery and for structural inequalities to be reinforced locally.</jats:p

Coproduire les services publics

The recurring floods experienced in recent years by many urban centres in West Africa are not merely the consequence of global climate change. Large parts of the poor urban populations in West Africa often live in hazardous areas where urban planning is inadequate and where the public services, infrastructure and protective regulations that are needed in order to face flood issues are poorly provided. As a result, recurrent flooding reinforces existing social inequalities and the vulnerability of the urban poor. This does, however, not mean that the delivery of collective services related to flood response does not exist or that it is ungoverned. In order to cope with inefficient public service provision, the inhabitants often organize to ensure that flooding is addressed. This study shows that in Pikine, a city located at the outskirts of Dakar (Senegal), the governance of floods entails the daily coproduction of flood prevention and adaptation services, where users play an important and active role. The authors show that this ‘palliative governance’ has a direct impact on vulnerable populations’ capacity to cope with and adapt to recurrent flooding. The authors show that the informality that is essential to the coproduction of services should not be seen as an opposition to the State, but rather as essential to the daily functioning of the state, as well as a manifestation of ordinary citizenship by residents of deprived neighbourhoods. &nbsp;Les dégâts causés par les fortes inondations qu’ont connues de nombreux centres urbains en Afrique de l’Ouest ces dernières années ne sont pas le seul fait des changements climatiques globaux, mais la résultante de facteurs structurels locaux tels qu’une urbanisation anarchique, le manque d’infrastructure et l’insuffisance des services de base, qui rendent particulièrement vulnérables les populations urbaines pauvres. Ces inondations tendent à renforcer les inégalités sociales et la vulnérabilité des plus pauvres face aux changements climatiques. Pour pallier au désengagement marqué de l’État et des municipalités en matière de services publics, les populations concernées s’organisent pour assurer la provision des services d’atténuation des inondations. Les auteurs de cet article montrent qu’à Pikine (dans la banlieue de Dakar, Sénégal) la gouvernance des inondations au quotidien se traduit par une coproduction des services dans laquelle les usagers jouent un rôle actif important. Cette « gouvernance palliative » a des répercussions directes sur la capacité d’adaptation et de prévention des risques liés aux changements climatiques des populations vulnérables. Les auteurs avancent que les initiatives locales et « l’informalisation » qui caractérisent la coproduction de ces services ne constituent pas une opposition à l’État, mais une mesure indispensable de son fonctionnement au quotidien et une manifestation de la citoyenneté ordinaire des habitants des quartiers urbains défavorisés. &nbsp

Dissolution of uranium dioxide in nitric medium, towards a macroscopic model of reactors

International audienceDissolution is a key step in several industrial processes. It is especially a milestone of the head-end of manyhydrometallurgical processes. For example, in recycling of spent nuclear fuel, the solubilization of the chemical elementsis essential before performing the liquid-liquid extraction steps to separate reusable material and final waste. One of themost complex scenarios is that of heterogeneous autocatalytic reactions. Today, there are few satisfying models forthese cases due to a lack of comprehension of their mechanisms.We focus here on the dissolution of uranium dioxide in nitric medium. In order to propose optimized processes fordissolution, this study aims at better understanding the chemical, physico-chemical and hydrodynamic phenomena ofsuch reactions. This study is also part of a modeling approach aiming, on one hand, at expressing the intrinsic reactionrates and describing the physico-chemical phenomena at interfaces and, on the other hand, at developing a generalmodel for dissolution reactors.Optical microscopy observation confirmed the highly autocatalytic nature of the reaction and led to measurements, forthe very first time, of "true" chemical kinetics of the reaction. The acid attack of sintering-manufactured solids occursthrough preferential attack sites. It develops cracks in the solids that can lead to their cleavage. This inhomogeneousattack is made possible by the establishment of bubbling in the cracks which allows periodic renewal of the reagents andthus maintains the reaction within the cracks. This point is a key component of the mechanism: a strong link among thedevelopment of cracks, bubbling through the cracks, and overall dissolution kinetics is demonstrated in this work.A model coupling material balance to the structural evolution of the solid and liquid phase compositions, and taking intoaccount the interfacial transport is proposed. The simulations based on this model are close to the experimentalobservations, and allow to replicate the effect of various reaction parameters for the very first time, such as the reductionof overall kinetics when turbulence increases

Detection of Epileptogenic Cortical Malformations with Surface-Based MRI Morphometry

Magnetic resonance imaging has revolutionized the detection of structural abnormalities in patients with epilepsy. However, many focal abnormalities remain undetected in routine visual inspection. Here we use an automated, surface-based method for quantifying morphometric features related to epileptogenic cortical malformations to detect abnormal cortical thickness and blurred gray-white matter boundaries. Using MRI morphometry at 3T with surface-based spherical averaging techniques that precisely align anatomical structures between individual brains, we compared single patients with known lesions to a large normal control group to detect clusters of abnormal cortical thickness, gray-white matter contrast, local gyrification, sulcal depth, jacobian distance and curvature. To assess the effects of threshold and smoothing on detection sensitivity and specificity, we systematically varied these parameters with different thresholds and smoothing levels. To test the effectiveness of the technique to detect lesions of epileptogenic character, we compared the detected structural abnormalities to expert-tracings, intracranial EEG, pathology and surgical outcome in a homogeneous patient sample. With optimal parameters and by combining thickness and GWC, the surface-based detection method identified 92% of cortical lesions (sensitivity) with few false positives (96% specificity), successfully discriminating patients from controls 94% of the time. The detected structural abnormalities were related to the seizure onset zones, abnormal histology and positive outcome in all surgical patients. However, the method failed to adequately describe lesion extent in most cases. Automated surface-based MRI morphometry, if used with optimized parameters, may be a valuable additional clinical tool to improve the detection of subtle or previously occult malformations and therefore could improve identification of patients with intractable focal epilepsy who may benefit from surgery

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Conception d'un procédé pour la production de microparticules filtrables et redispersables

Not availableCe travail concerne la précipitation de la silice, et plus précisément, la production d'un précipité de haute surface spécifique, filtrable et redispersable. Plusieurs processus sont alors à maitriser pour aboutir à ces caractéristiques : les vitesses de nucléation et de croissance modifient le nombre et la taille des nanoparticules constituant la silice précipitée. Elles auront donc une influence directe sur la surface spécifique. Les conditions d'agrégation et d'agglomération modifient quant à elles la taille et la cohésion finale du précipité. Elles auront alors une influence sur la filtrabilité et la redispersibilité du produit final. En vue de comprendre le déroulement de ces différentes étapes, nous les avons étudiées séparément. En mode semi-ferme, les mécanismes de nucléation et de croissance ont été analysés. La vitesse de nucléation a pu être estimée ; la vitesse de croissance a été mesurée, et une loi de croissance a été établie. En mode ferme, les phénomènes d'agrégation ont été étudiés, et les mécanismes d'agrégation ont pu être décrits par une cinétique en deux étapes. Les paramètres hydrodynamiques et physico-chimiques modifiant ce processus ont de plus été mis en évidence. Afin de maitriser les conditions de mélange des réactifs, un système original de mise en contact des réactifs par jets d'impact a été développé. Il permet de contrôler le déroulement des vitesses de nucléation et de croissance au cours de la précipitation, et constitue un critère de choix pour l'extrapolation du procédé à plus grande échelle. En mode semi-ferme, les jets d'impact ont permis l'optimisation de la surface spécifique et de la structure des agglomérats de silice, ainsi que l'obtention d'un produit aisément filtrable. La transposition du mode opératoire en continu nous a permis de nous affranchir du renforcement des agrégats observé en mode semi-ferme et nous a conduit à l'obtention d'un précipité de haute surface spécifique, filtrable et redispersable

Peer review experience in the teaching of chemical reaction engineering at ENSIC Nancy: Presentation and interest of such a methodology?

As recommended by various accreditation and evaluation bodies (EFCE, 2020), the contents of process engineering teaching syllabuses aim to build, in the sense of Bloom’s educational taxonomy, high levels of skills in analysis, synthesis, evaluation (Bloom et al., 1956). Considering on the one hand that the evaluation of learning outcomes corresponds to the highest levels of skills and on the other hand the existence of many other experiences in the field (Mac Raighne al., 2015, Yu and Su, 2015, Liauw, 2020, Smith et al., 2020), peer review was offered to students at ENSIC Nancy for teaching for teaching chemical reaction engineering of homogeneous and heterogeneous reacting systems engineering of homogeneous and heterogeneous chemical reactions. This method promotes active learning, in a constructive societal approach, allowing learners to identify and formulate their own problems to develop and increase their skills

Study of silica particle aggregation in a batch agitated vessel

International audienc

Étude et modélisation d'un procédé catalytique hétérogène d'estérification

Cette étude a pour objectif l'étude des processus impliqués dans la production de l'acrylate de 2-éthylhexyle, ester gras dérivé de l'acide acrylique. Cette réaction est accélérée par l'emploi d'un catalyseur solide, une résine acide sulfonée. Les interactions spécifiques des différents composés avec cette résine ont été étudiées à température ambiante. A 90C, le couplage avec la cinétique de réaction a été analysé et modélisé en réacteur fermé. Un montage pilote spécifique conçu au laboratoire a permis la réalisation de réactions dans un réacteur en lit fixe, dont la structure tripartite permet le suivi des concentrations liquides dans le montage. Une modélisation représentant cette installation a été mise au point, associant l'affinité sélective, la cinétique de réaction et l'hydrodynamique de l'écoulement. Ce modèle a ensuite été utilisé pour l'analyse de modèles de tendances, pour déterminer des conditions de fonctionnement améliorés d'un procédé de taille industrielleThis study aims at analyzing and understanding the processes involved in the production of 2-ethylhexyl acrylate. This fatty ester is a derivative of acrylic acid. This reaction is accelerated by the use of a solid catalyst, a sulfonated resin acid. The specific interactions of compounds with this resin were studied at room temperature. At 90C, the coupling of kinetics and selective affinity was analyzed and modeled in a closed reactor. A specific pilot installation was designed in laboratory. Esterification reactions were performed. in this fixed bed reactor. The tripartite structure allows the monitoring of liquid levels in all installation. A model representing this system was developed, involving selective affinity, kinetics and hydrodynamic. This model was then used to analyze trends models to determine improved operating conditions for an industrial size processMETZ-SCD (574632105) / SudocNANCY1-Bib. numérique (543959902) / SudocNANCY2-Bibliotheque electronique (543959901) / SudocNANCY-INPL-Bib. électronique (545479901) / SudocSudocFranceF