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Income Shocks, Bride Price, and Child Marriage in Turkey
No full textInternational audienceAbstract Early marriage persists in many countries in spite of legal prohibition. The role of income shocks and bride price norms is investigated in the context of Turkey. Using data from the Turkey Demographic and Health Surveys 1998 to 2018, rainfall shocks are exploited as an exogenous source of variation of household income. To study the role of marital payments, measures of shocks are interacted with a province-level indicator based on past prevalence of bride price. Estimation results show that girls exposed to a large negative shock during adolescence have a higher probability of being married before 15, if living in provinces with a high prevalence of bride price. More arranged and forced marriages are found after severe shocks in those provinces. Results suggest that daughter marriage, as a response to mitigate negative income shocks, is not limited to the poorest countries, and still contributes to household strategies in Turkey
Thermal preference plasticity in ectotherms: Integrating temperature affinity and thermoregulation precision
No full textInternational audienceThermal preference (Tp) prevents ectotherms from encountering sublethal temperatures. Its plasticity likely modulates the importance of behavioral thermoregulation under changing conditions. While it has been widely recognized that Tp varies across ontogeny, the plasticity level of this trait across life stages is poorly understood. We propose a novel conceptual framework relating two plastic components of Tp: its mean, which indicates temperature affinity, and its variance, which informs on the precision of behavioral thermoregulation. We tested this framework at the population scale by measuring Tp variations across life stages of an insect model after several generations under contrasting developmental temperatures. Tp plastic responses differed among life stages. Generally, we obtained a bell-shaped relationship between temperature affinity and precision of thermoregulation, indicating a strategy to avoid suboptimal and supraoptimal temperatures in Drosophila melanogaster, but not in all life stages. We highlight the need to change the paradigm underlying the study of Tp plasticity beyond the use of a single metric (median or range) to better comprehend thermoregulatory strategies
Bovine ampullary and isthmic epithelial spheroids: proteomic profile and physiological features for in vitro studies of gamete-oviduct interactions.
No full textInternational audienceAfter mating or insemination, spermatozoa reach the first part of the oviduct, known as the isthmus, where a subpopulation binds to the epithelial cilia, forming a reservoir. Then, spermatozoa migrate toward the ampulla, where additional interactions with cilia occur and fertilization takes place. Exploring sperm-oviduct interactions requires physiologically relevant in vitro models. Our goal was to characterize isthmic and ampullary epithelial spheroids in terms of cellular, proteomic and sperm binding properties. Spheroids measuring 100-150 µm in diameter, formed after a 3-day culture of pre-ovulatory oviduct mucosa fragments, were selected and analyzed for (i) epithelial, fibroblast and cilia markers by immunostaining, (ii) proteomic content by dia-PASEF nanoLC-MS/MS, and (iii) ability to interact with bull spermatozoa during a 6-h co-culture, assessed by confocal and scanning electron microscopy. Cells within both isthmic and ampullary spheroids showed positive immunostaining for cytokeratin and no staining for vimentin. Ampullary spheroids consistently exhibited a higher proportion of ciliated cells compared to isthmic spheroids (24.5 % vs 20 %; p < 0.05; variation coefficients among replicates of 15 and 11 %, respectively). A total of 6914 proteins were quantified, of which 1010 (14 %) were differentially abundant between isthmic and ampullary spheroids. Following co-culture, 95-97 % of bound spermatozoa were attached by their head to cilia of both spheroid groups. The density of bound spermatozoa was on average 33-45 % higher on ampullary compared to isthmic spheroids (p < 0.001). This study provides a well-differentiated oviduct epithelium model for in vitro investigations of gamete and embryo interactions with the oviduct
Multi-Step Sintering Process on Sol-gel Synthetized Lead-free BNT for Enhanced Temperature Stability of Relaxor Ferroelectric State and Energy Storage Properties
No full textInternational audienceBismuth sodium titanate (Bi₀.₅Na₀.₅TiO₃) is one of the most promising candidates for new dielectrics in energy storage applications. Our research is aimed at a better understanding of the properties of this material depending on the synthesis conditions, using different types of sintering process and using a modified citrate method to reach smaller grain size than with solid-state reaction. Using this synthesis method, we demonstrate that a high density of approximately 92% can be achieved at a low sintering temperature of 1050 °C by employing a multi-step sintering process to control the various stages of sintering and grain growth. This process also enabled us to synthesize samples with grain sizes three times smaller (approximately 0.606 µm) than those obtained through conventional sintering (approximately 1.829 µm). Our research also characterizes differences in electric properties by comparing permittivity. The results are more promising for multi-step sintering, independent of density. Finally, we observe a shift in the depolarization temperature, indicating a more stable relaxor phase of our Bi₀.₅Na₀.₅TiO₃ at 160 °C, compared to the typical 200 °C reported in the literature
Essais sur le rôle de la politique monétaire de la BEAC dans le développement économique de l’UMAC
No full textThe aim of this dissertation is to examine the effectiveness of the BEAC’s monetary policy and to discuss there forms that need to be implemented to strengthen its effectiveness. The first chapter analyzes the impact of monetary policy on inflation in the member states, and the foreign exchange reserves of the Central African Monetary Union (UMAC) using structural vector auto-regressive models. Our results show that during theperiod 2000-2022, BEAC’s monetary policy has no significant impact on the price dynamics of its member states. However, it has a significant impact on the dynamics of foreign exchange reserves of the Monetary Union .The second chapter focuses on determining the optimal level of precautionary reserves for CEMAC. Two models are used : (i) reserves holding costs precautionary model of Keungne and al (2024) and (ii) the social welfare optimization model of Drummond and Dhasmana (2008). Both models lead to the conclusion that during the period 2000-2022, BEAC does not have enough foreign exchange reserves to finance productive investments without compromising external stability. The third chapter examines the possibility of implementing a foreign exchange reserve accumulation strategy aimed at improving the productivity of UMAC economies in order to strengthen the effectiveness of its monetary policy using the model developed by Matsumoto (2022). Empirical results of the model calibrated using UMAC data and solved using the perfect foresight algorithm indicate that the implementation of this strategy depends on the magnitude of adverse shocks on the international liquidity of residents of the monetary union.L’objectif de ce travail est d’examiner l’efficacité de la politique monétaire de la BEAC, et de discuter des réformes à mettre en place pour renforcer son efficacité. Le premier chapitre analyse l’impact de la politique monétaire sur l’inflation des Etats membres, et les réserves de change de l’Union Monétaire de l’Afrique Centrale (UMAC) à l’aide de modèles vectoriels autorégressifs structurels. Les résultats obtenus montrent que sur la période 2000-2022, la politique monétaire de la BEAC n’a pas d’incidence significative sur la dynamique des prix de ses Etats membres. En revanche, elle a une incidence significative sur la dynamique des réserves de change sur la période 2008-2023.Le deuxième chapitre s’intéresse à la détermination du niveau optimal des réserves de précaution de l’UMAC. Deux modèles sont utilisés : (i) le modèle d’optimisation des coûts de détention des réserves de Keungne et al (2024), et le modèle d’optimisation du bien-être social de Drummond et Dhasmana (2008). Ces deux modèles indiquent que sur la période 2000-2022, la BEAC ne disposerait pas de suffisamment de réserves de change pour financer les investissements productifs sans compromettre la stabilité externe de sa monnaie. Le troisième chapitre examine la possibilité de mettre en place à la BEAC une stratégie d’accumulation des réserves de change visant à améliore la productivité des économies de l’UMAC afin de renforcer l’efficacité de sa politique monétaire à l’aide du modèle de Matsumoto (2022). Les résultats obtenus à partir du modèle calibré sur des données de l’UMAC et résolu à partir de l’algorithme de prévoyance parfaite "Perfect Foresight" insuggèrent que la mise en place de cette stratégie dépend de l’amplitude des chocs adverses sur la trésorerie internationale des agents économiques résidents
Toward a new ecosystem of musicological studies
No full textInternational audienceMusic is an essential part of European cultural and economic objectives. While this might seem to provide an opportunity for musicology, both music and the science that best represents it remain underrepresented in policy and scientific infrastructures. Part of the problem is the nature of musical artefacts themselves. Unlike tangible heritage fields such as archaeology and visual arts, musical heritage spans both tangible and intangible elements—scores, instruments, oral traditions, data, (recorded) sound—that can be utilized for both research and commercial purposes. The diverging viewpoints on music as an industry and music as a domain of research have resulted in the limited integration within European heritage and digital infrastructures of both music and musicology.In order to chart new and sustainable paths for the field, EarlyMuse has been launched as the first Cooperation in European Science and Technology (COST) Action devoted to historical musicology (https://earlymuse.eu). A principal aim of EarlyMuse’s four-year programme (2024-2026) is to define new paths for musicological research in Europe in the domains of education, publications, sources, performances, and policies. Nearly 300 researchers from 40 countries across Europe and beyond are sharing data, analyses, and ambitions to provide inspiration for shifting the scientific and cultural policies of the European Union and its partners. By analysing the institutional challenges and opportunities our field faces, we are identifying new ways in which the discipline can position itself to meet the demands of the future.In this presentation, we will illuminate the organisation of our Action and the results of our work so far. Our intention is to demonstrate that, despite the challenges of integrating musical heritage and data into European infrastructures, there are unprecedented opportunities for musicology—but we must be ready to seize them