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A reelection-seeking politician makes a policy decision that can reveal her private information. This information bears on whether her political orientation and capabilities will be a good fit to future circumstances. We study how she may choose inappropriate policies to hide her information, even in the absence of specific conflicts of interests, and how voters' conformism affects her incentives to do so. Conformism is independent from policies and from voters' perceptions. Yet we identify a 'conformism advantage' for the incumbent that exists only when there is also an incumbency advantage. Conformism changes the incentives of the incumbent and favors the emergence of an efficient, separating equilibrium. It may even eliminate the pooling equilibrium (that can consist in inefficient persistence). Conformism has a mixed impact on social welfare however: it improves policy choices and the information available to independent voters, but fosters inefficient reelection in the face of a stronger opponent. When the incumbent is 'altruistic' and values social welfare even when not in power, she partly internalizes this latter effect. The impact of conformism is then non monotonous.

Partial nephrectomy is the treatment of choice for small localized renal tumors. In case of doubt, a biopsy can confirm the diagnosis. The aim of this study was to evaluate the impact of a delayed time to partial nephrectomy on cancer development.Our single center study enrolled localized renal tumor patients who underwent a partial nephrectomy between 2015 and 2020; the collected data were included in the uroCCR prospective database. The histopathological stage of the tumors and the recurrence rate in patients treated with surgery90 days after diagnosis were investigated. The impact a preoperative biopsy on was also explored. Statistical significance was tested using Student's t-test and Chi-squared test (SPSS software).The cohort consisted of 179 patients, among which 41 (23 %) received a preoperative biopsy. 89 patients (50 %) were treated surgically3 months after diagnosis. The median time to nephrectomy was 86 days (13-1 037). A delayed time to surgery did not lead to significantly higher recurrence rates (P=0.66). Preoperative biopsy led to a doubling time to surgery (P0.001) but was neither correlated to a more severe tumor stage (P=0.944) nor to a higher recurrence rate (P=0.08). Tumor growth was not significantly different with or without the presence of a biopsy (P=0.122).Our data evidence that a substantial delayed time to partial nephrectomy does not result in a negative impact on cancer prognosis in localized renal tumor patients.

National audience; We conducted an artefactual field experiment in Vietnam to investigate whether and how experiencing a natural disaster affects individual attitudes toward risks. Using experimental and real household data, we show that households in villages affected by a flood in recent years exhibit more risk aversion, compared with individuals living in similar but unaffected villages. Interestingly, this result holds for the loss domain, but not the gain domain. In line with Prospect Theory, Vietnamese households distort probabilities. The distortion is related to aid received and social networks participation, but is unrelated to flood experience.

International audience; Vietnam is one of the countries most affected by floods. Despite high exposure to this risk and repeated calls from international organizations, the penetration rate of flood insurance remains surprisingly low in Vietnam. We investigate if there is a demand for flood insurance by Vietnamese households using a choice experiment. We compute households' willingness to pay (WTP) for various flood insurance programs and we identify the relationships between WTP and the different attributes of insurance schemes (type of risk covered, level of coverage, insurance provider, billing frequency, insurance premium). We first show that Vietnamese households exhibit a strong preference for the status quo option (no insurance). We do, however, document significant and positive WTP for some flood insurance policies, especially those covering health expenses. We show that household trust in institutions providing flood insurance policies may help understand the currently low adoption rate. Finally, we stress the high degree of heterogeneity in household preferences for flood insurance policies: past experience with flooding, individual risk preferences and subjective flood risk perception matter to understand WTP for flood insurance. These results call for a very careful design of flood insurance mechanisms in Vietnam, and more generally in developing countries subject to high risks of natural disasters.

International audience; The G-protein-coupled receptor accessory protein MRAP2 is implicated in energy control in rodents, notably via the melanocortin-4 receptor1. Although some MRAP2 mutations have been described in people with obesity1-3, their functional consequences on adiposity remain elusive. Using large-scale sequencing of MRAP2 in 9,418 people, we identified 23 rare heterozygous variants associated with increased obesity risk in both adults and children. Functional assessment of each variant shows that loss-of-function MRAP2 variants are pathogenic for monogenic hyperphagic obesity, hyperglycemia and hypertension. This contrasts with other monogenic forms of obesity characterized by excessive hunger, including melanocortin-4 receptor deficiency, that present with low blood pressure and normal glucose tolerance4. The pleiotropic metabolic effect of loss-of-function mutations in MRAP2 might be due to the failure of different MRAP2-regulated G-protein-coupled receptors in various tissues including pancreatic islets.

Le renouvellement regulier des contrats de concession apparait necessaire pour beneficier de concurrence dans certains secteurs, comme l'eau. Nous decrivons les contrats et la regle de renouvellement optimaux dans ce contexte. Ils arbitrent entre les diminutions de couts, en cas de changement de concessionnaire, et les incitations a investir a long terme du concessionnaire en place. La meilleure information du concessionnaire en place sur des elements constituant une valeur commune de la concession est importante. Nous montrons que ses consequences different fortement du cas des encheres de biens.

The application of defined specific starter strains and their influence on microbiological, biochemical and sensory characteristics were studied during ripening of Venaco cheese, a traditional Corsican raw milk cheese manufactured with goat's or ewe's milk. Three defined starter blends, composed of wild strains of lactic acid bacteria, were tested. The first blend was composed of 2 strains of Lactococcus lactis subsp. lactis (ratio 1:1) and was used as a control. The second was composed of 3 strains, the two Lactococcus strains used in the first starter blend in addition to a strain of Lactobacillus paraplantarum (ratio 2:2:1). The third blend was also composed of 3 strains, the same two lactococci used in the first blend in addition to a strain of Leuconostoc mesenteroides subsp. mesenteroides (ratio 2:2:1). The experiment was carried out, in duplicate, at two cheese dairies. The first dairy transforms raw goat's milk and the second transforms raw ewe's milk. DNA fingerprinting of cheese isolates using the Rep-PCR technique showed that strains inoculated in milk established themselves in cheese. Lactococci and Ln. mesenteroides subsp. mesenteroides strains were present until the end of ripening, while Lb. paraplantarum was detected in cheese only during the first 15 d. Indigenous lactic microflora were found throughout ripening, showing a balance between this microflora and the starter strains. Goat's and ewe's milk cheeses made with Leuconostoc had the highest level of proteolysis, and those made with Lactobacillus, the highest level of lipolysis. These physico-chemical modifications led to significant differences in cheese sensory characteristics assessed by the triangle test., Utilisation de ferments lactiques spécifiques pour la fabrication du fromage Venaco. L'utilisation de levains lactiques sélectionnés spécifiques et leur influence sur les caractéristiques microbiologiques, biochimiques et sensorielles ont été évaluées durant l'affinage du fromage Venaco, un fromage traditionnel corse au lait cru de chèvre ou de brebis. Trois levains définis, composés de souches " sauvages " de bactéries lactiques, ont été testés. Le premier constitué de 2 souches de Lactococcus lactis subsp. lactis (ratio 1:1) était utilisé comme témoin. Le second était composé de 3 souches, la paire de lactocoques utilisée dans le premier ferment associée à une souche de Lactobacillus paraplantarum (ratio 2:2:1). Le troisième ferment comprenait la même paire de lactocoques associée à une souche de Leuconostoc mesenteroides subsp. mesenteroides (ratio 2:2:1). L'expérimentation a été menée dans deux fromageries, la première transformant du lait cru de chèvre, la seconde du lait cru de brebis. Chaque essai a été répété 1 fois. Le typage génétique des isolats collectés des fromages à l'aide de la technique Rep-PCR a montré que les souches inoculées dans le lait s'implantaient dans le fromage. Les souches de lactocoques et de Ln. mesenteroides subsp. mesenteroides étaient présentes jusqu'à la fin de l'affinage, la souche de Lb. paraplantarum jusqu'à 15 j d'affinage. Les bactéries lactiques de la microflore indigène étaient retrouvées durant l'affinage, traduisant un certain équilibre entre cette microflore et les souches du levain. Les fromages de chèvre et de brebis fabriqués avec la souche de lactobacille étaient les plus lipolysés, tandis que l'indice de protéolyse le plus élevé était obtenu avec le ferment contenant la souche de leuconostoc. Ces modifications physico-chimiques conduisaient à des différences significatives des propriétés sensorielles du fromage évaluées par un test triangulaire.

An analytical model of steady gaseous flows through rectangular microducts with second-order boundary conditions is proposed. It completes previous studies on flows in circular microtubes or between parallel plates found in the literature. The influence of the second-order terms and of the geometric parameters is analyzed. It is shown that the mass flow rate is underestimated when second-order terms are not taken into account and that these terms become more significant when the cross section of the microduct tends to a square cross section. Difficulties in obtaining exploitable experimental comparisons, due to problems in the determination of the Maxwell reflection coefficient σ v , are also discussed

The oxidoreduction potential (E h) is of growing interest in dairy research and the dairy industry. Lactic acid bacteria are able to decrease the E h to considerable reducing values, and it is an important feature of the technological characteristics of lactic starters and probiotics. Reducing E h is also necessary for the development of the characteristic flavour of certain fermented dairy products such as cheeses. Moreover, data comparisons and interpretations are often difficult due to an absence of standardised expression of the results. The objective of this work was to propose a complete procedure for the use of combined and half-cell platinum (Pt) sensors to obtain stable, repeatable and reproducible E h measurements and to standardise data. Three measurement systems, each made up of a sensor, cable and interface, were compared in tap water. A control chart was used to calculate a confidence interval (CI = 20 mV) to verify whether the process was under control. This complete procedure was then applied to the measurement of E h in milk samples to characterise both pure strains of lactic acid bacteria and complex mixed starters, to study the impact of a process parameter (oxygen) on starter activity, to follow E h during cheese making and to measure E h gradients in cheeses. This manuscript presents a procedure for the measurement of E h as well as the feasibility and interest of this procedure in the dairy chain.

International audience; We empirically investigate the determinants of household flood protective strategies and risk perception using data from a household-level survey conducted in spring 2012 in Vietnam. Our empirical analysis shows that some flood protective behaviours of Vietnamese households are driven by the perception of flood risks, a result consistent with the Protection Motivation Theory (PMT). Our results also suggest that both perceived probabilities and perceived consequences of floods are related to some cognitive processes included in the PMT. Lastly, we document the important role played by public flood management policies in shaping individual flood risk perception and protective behaviours.

Introduction La deficience visuelle est un facteur predictif important de chute chez les personnes âgees et pourrait alterer le comportement postural lors d’une tâche visuelle en position debout. Quel est donc l’effet d’une acuite visuelle et d’un contraste faibles sur le mouvement de prehension et la cinetique posturale lors de la saisie d’un objet ? Materiel et methodes Trente et un jeunes adultes droitiers debout sur 2 plateformes de force devaient saisir avec leur main droite 2 cubes (un bleu a fort contraste et un jaune a faible contraste) parmi des objets distracteurs sur une table placee devant eux. Les conditions visuelles etaient normales (10/10 e ) ou modifiees grâce a une paire de lunettes simulant une acuite visuelle de 1/10 e . Les mouvements 3D de la main droite etaient analyses ainsi que la composante sagittale des forces de reaction du sol (FRSsag) et la position de leur origine (centre de pression, CP) par rapport aux pieds. Resultats La main droite mettait significativement plus de temps pour demarrer le mouvement, s’approcher du cube et toucher le cube en condition de faible acuite visuelle par rapport a celle d’acuite normale pour les 2 cubes, et, en faible acuite, pour le cube jaune par rapport au cube bleu. Au contact du cube, la position anterieure du CP ne differait pas pour les 4 conditions alors que la FRSsag etait significativement plus vers la gauche par rapport au depart dans les 4 conditions et de facon plus importante, en faible acuite, pour le cube jaune que le cube bleu. Discussion – conclusion Le temps passe pres de l’objet avant de le toucher et l’asymetrie concomitante d’appui des pieds, augmentes par une faible acuite visuelle et un faible contraste de l’objet, pourraient etre des facteurs d’instabilite posturale, potentiellement deleteres s’ils etaient mis en evidence chez la personne âgee deficiente visuelle.

International audience; Credit agents in microfinance institutions (MFIs)must be given incentives to aquire information on potential borrowers and select them in accordance with the MFI's objectives. We show that while giving incentives has no cost in for-profit MFIs, it is costly in pro-poor MFIs: We repayment and wealth are positively correlated, a pro-poor MFI cannot obtain the selection of poor clients in the proportion it wishes with incentives based solely on repayment. It then becomes necessary to audit the share of very poor borrowers selected by an agent in order to provide the latter with adequate incentives. When audit costs are large, pro-poor MFIs may have to forego selection on wealth and use other targeting devices such as working empoverished geographical locations. Driven by donor concerns with 'mission drift' away from the poor, audits on the wealth status of clients have been introduced at the level of MFIs. We show that introducing pro-poor incentives requires extending such audits to the level of credit agents.

Microlens, micromirrors, quantum dots and microfluidics networks are some elements illustrating the need of miniaturisation for optics. This paper presents examples of high aspect ratio microstructures obtained with Dilase technology, a direct laser lithography technique in photosensitive layers. Vectorial writing associated with specific laser beam treatment allows imagine fast prototyping and production of a large range of MOE. Integrated optical circuits, such as optical MUX/DEMUX and splitters are strongly used in telecommunication and sensors industries. Microlens arrays, micromirrors present a large potential for imagery sector. "Lab on a chip" integrating microfluidic and optical waveguides systems are useful for medical diagnosis.

Regulators often do not regulate all firms competing in a given sector. Due to product substitutability, unregulated competitors have incentives to bribe regulated firms to have them overstate their costs and produce less, thereby softening competition. The best collusion-proof contract entails distortions both for inefficient and efficient regulated firms (distortion ‘at the top’). But a contract inducing active collusion may do better by allowing the regulator to ‘team up’ with the regulated firm to indirectly tax its competitor. The best such contract is characterized. It is such that the unregulated firm pays the regulated one to have it truthfully reveals its inefficiency. We finally compare those contracts.

Two agents sequentially contracts with different principals under moral hazard. If agents care for one another, the second principal gains by insuring them over first wages. Even with independent tasks, the first principal must offer riskier payments to induce effort.

International audience; Antitrust authorities have set up leniency programs for cartel members that denounce their collusive agreements. These programs help prosecute participants and can thereby deter collusion. We compare the impact of reduced fines and positive rewards and argue that rewarding individuals, including firm employees, can deter collusion in a more effective way. We discuss possible adverse effects of whistle-blowing programs on firms' behavior, and particularly on turnover, incentives to innovate and cooperation. We also explore explanations for the puzzling fact that managers keep incriminating evidence and argue reward programs actually provide additional incentives for keeping such evidence.

International audience; The impact of regulation of efforts to minimize costs has been widely discussed, but remains difficult to measure. The sophisticated regulation of water utilities in Wisconsin allows us to attempt such on assessment since different firms can be under different regulatory regimes (price cap or rate-of-return) in the same geographical area at the same time. To measure the impact of regulation on efficiency, we use a stochastic cost frontier approach defining the unobservable efficiency of a water utility as a function of exogeneous variables. Using a panel of 211 water utilities observed from 1998 to 2000, we show that their efficiency scores can be partly explained by the regulatory framework.

Le potentiel d'oxydoreduction (Eh) est un parametre intrinseque a tout milieu biologique. Il peut intervenir a differents niveaux sur la cellule microbienne : expression des genes, metabolisme, physiologie et donc modifier potentiellement son aptitude a la croissance et a la production de molecules participant aux caracteristiques finales des produits fermentes. En fonction des types de produits, il existerait un Eh optimal pour le developpement des flores et d'une balance aromatique equilibree. Il apparait donc important de definir des criteres de mesure des aptitudes reductrices des differentes souches de bacteries utilisees en industrie. Ce type de demarche a permis de differencier les potentialites de bacteries lactiques et de ferments commerciaux.

This paper represents an initial analysis of unsteady gaseous flows in a rectangular microchannel under usual pressure and temperature conditions. The effect of depth and aspect ratios of the cross-section is investigated. With most fluid-based mechanical microsystems of small internal dimensions and subject to normal pressure and temperature conditions, flow is rarefied with slip at the walls. This flow is then modeled by the Navier-Stokes equations combined with slip and temperature jump conditions at the walls. These conditions are represented by Maxwell-Smoluchowski first order equations. By concentrating essentially on the pulsed sinusoidal regime, it is shown that the instantaneous flow rate amplitude, as well as the band pass of the microchannel are underestimated when slip at the walls is not taken into account. The frequency response of two microchannels connected in series with different cross-sectional areas is also studied. Finally, the proposed model can serve as a tool giving information about the current feasibilities of pressure sensors for the measurement of the dynamic characteristics of gaseous flows in microchannels.

SummaryWe study the welfare impact of enforcing a competitive behavior from an unregulated fringe competing with a regulated dominant operator, with imperfectly differentiated goods. The fringe is potentially collusive but may be supervised by a competition authority. We show that the complementarity/substitutability between regulation and competition policy strongly depends on the nature of the market interaction.Forcing the fringe to adopt a competitive behavior always benefits consumers. However, it also affects the amount of subsidy that must be provided to the regulated firm for cost-reimbursement purposes, which has a social cost when public funds are costly. With complements, antitrust intervention is always welfare-improving. It is also preferable with weak substitutes, but is detrimental to welfare for strong substitutes.

During the last decade, Latin American countries have brought about important reforms in infrastructure services based both on private sector participation for enhancing internal efficiency and competition for increasing consumer welfare. Infrastructure services have evolved from monopoly and public ownership setting lacking specific regulations, toward scenarios where private participation prevails, with competition and regulation playing complementary roles. However, even though competition is a pivotal feature in all public service reform processes, a high degree of vertical and horizontal concentration pervades the industrial structure of many countries in the region. Furthermore, mergers and acquisitions taking place in the context of an increasingly global economy, without the appropriate legislation geared at promoting competition and restraining market control, have often led to reduced levels of competition. Competition Policy in Regulated Industries identifies competition problems in infrastructure sectors, discusses legal and structural solutions to them, and provides conceptual and practical approaches for emerging economies.

This thesis studies the role of social conformity in voting. In the first chapter, we presentthe definition of social conformity in social psychology. We review key elements of literature in order toshow the influence of conformity. In the second chapter, we conduct a literature review on the economicrole of conformity, which brings together work in experimental economics and social psychology. In thethird chapter, we present theoretical models in behavioral economics studying the role of conformity.On this basis, the fourth chapter is devoted to an economic approach to modeling the preferencesof conformity as voters’ desire to win in a re-election under Majority rule. Concretely, we offer anexplanation about how voters’ desire to win can deter incumbents from inefficient decisions while inoffice. In the fifth chapter, the thesis comes to model conformity preferences as desire to make the samevote as the majority in voting for collective decision-making under the unanimity rule. The findingsof the model highlight that conformity preferences can improve the sum of voters’ social welfare andalleviate the free-rider problem. Though conformity has always had a bad reputation, all our resultsshed light on its usefulness in various contexts to vote.; Cette thèse étudie le rôle du conformisme social dans un contexte de vote. Dans le premierchapitre, nous présentons la définition, en psychologie sociale, du conformisme. Nous passons enrevue les éléments cl´es de la littérature afin de montrer l’influence du conformisme. Dans le deuxièmechapitre, nous procédons `a une revue de la littérature sur le rôle économique du conformisme, quirassemble des travaux en économie expérimentale et en psychologie sociale. Dans le troisième chapitre,nous présentons des modèles théoriques en économie comportementale étudiant le rôle du conformisme.Sur cette base, le quatrième chapitre est consacré `a une approche économique de la modélisation despréférences conformistes lorsque les électeurs souhaitent voter pour le candidat vainqueur, lors d’uneélection sujette `a la règle de la majorité. Concrètement, nous proposons d’expliquer comment le désirdes électeurs de voter pour le gagnant peut dissuader le candidat sortant de prendre des décisionsinefficaces pendant son mandat `a des fins de réélection. Dans le cinquième chapitre, nous présentonsun modèle intégrant des préférences conformistes, comme le désir de faire le même choix que lamajorité, lors d’un vote `a l’unanimité. La résolution du modèle permet de mettre en évidence qu’unepréférence pour se conformer au comportement d’autrui peut améliorer le bien-être social des votantset atténuer le problème du passager clandestin. Bien que le conformisme ait toujours eu une mauvaiseréputation, tous nos résultats mettent en lumière son utilité dans divers contextes de vote.

This thesis studies the role of social conformity in voting. In the first chapter, we presentthe definition of social conformity in social psychology. We review key elements of literature in order toshow the influence of conformity. In the second chapter, we conduct a literature review on the economicrole of conformity, which brings together work in experimental economics and social psychology. In thethird chapter, we present theoretical models in behavioral economics studying the role of conformity.On this basis, the fourth chapter is devoted to an economic approach to modeling the preferencesof conformity as voters’ desire to win in a re-election under Majority rule. Concretely, we offer anexplanation about how voters’ desire to win can deter incumbents from inefficient decisions while inoffice. In the fifth chapter, the thesis comes to model conformity preferences as desire to make the samevote as the majority in voting for collective decision-making under the unanimity rule. The findingsof the model highlight that conformity preferences can improve the sum of voters’ social welfare andalleviate the free-rider problem. Though conformity has always had a bad reputation, all our resultsshed light on its usefulness in various contexts to vote., Cette thèse étudie le rôle du conformisme social dans un contexte de vote. Dans le premierchapitre, nous présentons la définition, en psychologie sociale, du conformisme. Nous passons enrevue les éléments cl´es de la littérature afin de montrer l’influence du conformisme. Dans le deuxièmechapitre, nous procédons `a une revue de la littérature sur le rôle économique du conformisme, quirassemble des travaux en économie expérimentale et en psychologie sociale. Dans le troisième chapitre,nous présentons des modèles théoriques en économie comportementale étudiant le rôle du conformisme.Sur cette base, le quatrième chapitre est consacré `a une approche économique de la modélisation despréférences conformistes lorsque les électeurs souhaitent voter pour le candidat vainqueur, lors d’uneélection sujette `a la règle de la majorité. Concrètement, nous proposons d’expliquer comment le désirdes électeurs de voter pour le gagnant peut dissuader le candidat sortant de prendre des décisionsinefficaces pendant son mandat `a des fins de réélection. Dans le cinquième chapitre, nous présentonsun modèle intégrant des préférences conformistes, comme le désir de faire le même choix que lamajorité, lors d’un vote `a l’unanimité. La résolution du modèle permet de mettre en évidence qu’unepréférence pour se conformer au comportement d’autrui peut améliorer le bien-être social des votantset atténuer le problème du passager clandestin. Bien que le conformisme ait toujours eu une mauvaiseréputation, tous nos résultats mettent en lumière son utilité dans divers contextes de vote.