Le fer joue un rôle crucial dans de nombreuses fonctions biologiques et est indispensable ‎au fonctionnement optimal du corps, tant au niveau systémique que cellulaire. Des ‎études ont rapporté des associations entre des taux de fer anormaux et certaines ‎maladies cardiovasculaires (MCV) et neurodégénératives (MND). Toutefois, la direction de ‎l’influence de ces associations n’est pas clairement identifiée. Dans ce projet, nous ‎utilisons des données génétiques sommaires et des méthodes statistiques et ‎computationnelles pour élucider le lien entre le taux de fer et certaines MCV et MND. ‎Nous avons effectué une méta-analyse des résultats de plusieurs études de cohortes sur ‎les taux de fer dans le sang, évaluant les corrélations génétiques et l’effet causal du taux ‎de fer sur 11 traits MCV et MND en utilisant la randomisation mendéliennes (RM). Nous ‎avons identifié des corrélations génétiques globales significatives entre le fer sérique et 4 ‎traits : les lipoprotéines à haute densité (HDL), les triglycérides, la maladie coronarienne ‎et l'insuffisance cardiaque, ainsi que 194 régions génomiques présentant des ‎corrélations locales significatives. Les analyses de RM suggèrent un rôle protecteur du fer ‎sérique sur le métabolisme lipidique, en particulier sur le cholestérol total et le ‎cholestérol non HDL. De plus, les analyses stratifiées par sexe indiquent un potentiel rôle ‎protecteur du fer contre la maladie de Parkinson chez les femmes. Les résultats de ce ‎projet permettront de développer nos connaissances sur les bases génétiques qui sous-‎tend le taux de fer et les MCV et MND, ouvrant ainsi la voie à de nouvelles interventions ‎préventives et thérapeutiques pour ces maladies.‎ / Iron plays a crucial role in numerous biological functions, and it is essential for optimal ‎body functioning, both at the systemic and cellular levels. Studies have reported ‎associations between abnormal iron levels and certain cardiovascular (CVD) and ‎neurodegenerative diseases (NDD). However, the direction of influence of these ‎associations is not clearly identified. In this project, we utilize genetic summary statistics ‎data and advanced statistical and computational methods to elucidate the link between ‎iron levels and specific CVD and NDD. We conducted a meta-analysis of results from ‎multiple cohort studies on serum iron levels to then assess genetic correlations and ‎causal effects of iron levels on 11 CVD and NDD using Mendelian randomization (MR). ‎We identified significant global genetic correlations between serum iron and 4 traits: ‎high-density lipoprotein (HDL) cholesterol, triglycerides, coronary artery disease, and ‎heart failure, among which 194 genomic regions showing significant local correlations. ‎MR analyses suggest a protective role of serum iron on lipid metabolism, particularly on ‎total cholesterol and non-HDL cholesterol. Furthermore, sex-stratified analyses suggest ‎a potential protective role of iron against Parkinson’s disease in females. The findings of ‎this project will advance our understanding of the genetic basis underlying iron levels and ‎CVD and NDD risk, paving the way for new preventive and therapeutic interventions for ‎these diseases.‎

This dissertation aims to develop statistical methodologies for estimating the effects of time-fixed and time-varying factors in recurrent events modeling context. The research is motivated by the traffic safety research question of evaluating the influence of crash on driving risk and driver behavior. The methodologies developed, however, are general and can be applied to other fields. Four alternative approaches based on various data settings are elaborated and applied to 100-Car Naturalistic Driving Study in the following Chapters. Chapter 1 provides a general introduction and background of each method, with a sketch of 100-Car Naturalistic Driving Study. In Chapter 2, I assessed the impact of crash on driving behavior by comparing the frequency of distraction events in per-defined windows. A count-based approach based on mixed-effect binomial regression models was used. In Chapter 3, I introduced intensity-based recurrent event models by treating number of Safety Critical Incidents and Near Crash over time as a counting process. Recurrent event models fit the natural generation scheme of the data in this study. Four semi-parametric models are explored: Andersen-Gill model, Andersen-Gill model with stratified baseline functions, frailty model, and frailty model with stratified baseline functions. I derived model estimation procedure and and conducted model comparison via simulation and application. The recurrent event models in Chapter 3 are all based on proportional assumption, where effects are constant. However, the change of effects over time is often of primary interest. In Chapter 4, I developed time-varying coefficient model using penalized B-spline function to approximate varying coefficients. Shared frailty terms was used to incorporate correlation within subjects. Inference and statistical test are also provided. Frailty representation was proposed to link time-varying coefficient model with regular frailty model. In Chapter 5, I further extended framework to accommodate multi-type recurrent events with time-varying coefficient. Two types of recurrent-event models were developed. These models incorporate correlation among intensity functions from different type of events by correlated frailty terms. Chapter 6 gives a general review on the contributions of this dissertation and discussion of future research directions. / Ph. D.

Video games' capacity for player choice makes them an excellent medium for expressing ethical dilemmas and developing the ethical thinking of players. However, translating complex ethical dilemmas to procedural games is challenging, particularly when the game creator intends to convey specific arguments in their work. This paper contains a close reading of ethical dilemmas in Fallout: New Vegas, Disco Elysium, and Frostpunk and applies Deleuze and Guattari’s (1987) concept of stratification as a means of understanding the process of collapsing the semantics of an ethical dilemma into the procedures of a digital game. It introduces the concept of consonance to refer to the consistency between procedural and semantic logic, and argues that the development of mechanics which maintain or enhance consonance is an important factor in creating persuasive procedural rhetoric about ethical topics.

This phenomenological case study explores the college and career readiness (CCR) and postsecondary trajectories of six African American youth, 18 to 20 years of age, who attended or graduated from a northeastern urban school district during 2021 to 2022. Drawing on social reproduction theory and critical race theory, interviews, school, district and demographic data were examined to understand how participants made meaning of their CCR experiences and the family, school, work, and community influences on their postsecondary trajectories. Findings demonstrated that the youth used community cultural wealth to support their education and career goals and to navigate structures and systems. However, as participants pursued their aspirations, dominant White capital (social, financial, and temporal) in education and employment structures increasingly created barriers to their goals. Participants continued to aspire toward their dreams; however, the obstacles they confronted and their ability to navigate those obstacles varied by parental educational and occupational background. In order to ready African American youth for postsecondary success, participants recommended that CCR school implementation (a) engage with students one on one and not rely on computers; (b) ready students for good-paying jobs as well as college; (c) employ caring, culturally responsive educators and staff with high expectations; (d) offer more creative and critical thinking learning experiences and a less regimented curriculum; and (e) provide support for postgraduation transition. This research has implications for social reproduction, Black habitus, caste, and intergenerational mobility. / Urban Education

In response to climate change, economic instability, and rapid urbanization, the notion of urban resilience has gained prominence in city planning and governance. Urban resilience is the ability of a system to adapt to new baseline conditions developing as a result of disturbances. This study is focused on one of urban resilience’s sub-tenets, ecological resilience. Ecological resilience is the ability of a system to sustain ecosystem services following a disturbance (i.e. droughts, flooding, heat waves). The health of the environment prior to a disturbance informs post-disturbance ecological resilience. An already stressed and unbalanced system, or an ecosystem with degraded health, is predisposed to vulnerabilities and exposure to disturbances. Environmental injustice is a significant gauge of latent environmental harm, and subsequently degraded ecosystem functionality. This study explores the spatial distribution and correlation between socioeconomic and environmental burdens in the largest majority Black neighborhood in the City of Orlando, Parramore. Through a lens of environmental justice, identifying where environmental, social, and economic harm is amplified and who is affected provides greater contextual information for the focus of future resilience strategies, the process through which they are devised and implemented, and their connection to land use planning and policy.

It has long been established that women play unique roles within schools, volunteerism, and school-based community work (Griffith and Smith 2005; Calarco 2020; Lewis and Diamond 2015; Posey-Maddox 2014). Additionally, research suggests that the work done surrounding the institution of education primarily falls on mothers (Griffith and Smith 2005; Haley-Lock and Posey-Maddox 2016; Lareau 2000; Lareau 2011). However, little research has been done that explores how gender dynamics play out in education activism that lies outside of schools. This study seeks to understand how women view gendered expectations of mothering work in regard to education and if/how they perceive that work in relation to their political activism. This study aids in better understanding how activists perceive the roots of their activist work and provide insights about political activism surrounding education. As activism surrounding education can greatly contribute to achieving a more just and equitable society, this work is crucial for scholarship seeking to understand the activists attempting to change our education system.

Vor dem Hintergrund der Auflösung der DDR als besonderes historisches Ereignis, welches alle Generationen in gewisser Weise tangiert, setzt sich die Studie mit der Frage auseinander, welchen Einfluß objektive Bedingungen und die damit verbundene Funktionsweise der Individuen in der Gesellschaftsstruktur auf die Vorstellungen über die Erziehung von Kindern und auf die Vorstellung über Individualität und Unterordnung haben. Drei Generationen stehen im Mittelpunkt der Untersuchung, deren Lebensverläufe eng mit den beiden Weltkriegen, dem Wirtschaftswunder, der Teilung Deutschlands und den wirtschaftlichen und sozialstrukturellen Veränderungen in Deutschland verbunden sind bzw. waren. Dabei wird auch nach Ost- und Westdeutschland unterschieden. Diese drei Generationen werden zum einen in ihrem zeitgeschichtlichen Kontext beschrieben und zum anderen in Beziehung gesetzt mit bedeutenden sozialisationstheoretischen Ansätzen der jeweiligen Zeit. Dazu gehört die Autoritarismustheorie der Frankfurter Schule, die Theorie zur schichtspezifischen Sozialisation von Melvin Kohn und die Theorie des Wertewandels von Ronald Inglehart. Die jeweiligen Theorien werden dabei als Hypothesen behandelt, deren Gültigkeit beim Vergleich der Werte zwischen den Generationen überprüft wird. Dafür werden die Familiensurvey-Erhebungen des Deutschen Jungendinstitutes in München als empirische Basis genutzt. / Against the background of a disappearing East German state - a historic event which affected all generations to varying degrees – this study examines the effect that prevailing conditions and the resultant functioning of individuals within the social structure had on people’s approaches to childrearing and to individuality and subordination. The study focuses on three generations whose life courses were or still are closely linked with two world wars, the post-war economic miracle, the division of Germany and major economic and socio-structural changes within Germany. Distinctions are also made between East and West Germany. The three generations are on the one hand described within their respective historical contexts, and on the other examined in the light of the prominent socialisation theories of their time. These include the authoritarianism theory of the Frankfurt School, the theory of class-specific socialisation by Melvin Kohn, and Ronald Inglehart’s theory of value change. These theories are treated as hypotheses, the validity of which is tested by comparing the values identified for the different generations. The family surveys carried out by the Munich-based Deutsches Jugendinstitut form the empricial basis for this work.

L'objectif principal de cette thèse est la caractérisation des dynamiques hautes fréquance en milieu côtier et en particulier leurs extrêmes, par l'intermédiaire de l'étude de série temporelle biogéochimiques à long terme enregistrées par des systèmes automatisés. Les bases de données hautes fréquences utilisées dans cette étude proviennent majoritairement du programme MAREL, qui a été mise en oeuvre par l'IFREMER. Des séries temporelles basses fréquences provenant des programmes de surveillance du littoral SOMLIT (CNRS, INSU) et SRN (Ifremer) sont mises à contribution pour appuyer l'importance des systèmes automatisés. La méthode EMD (Empirical Mode Decomposition) nous a servi de base dans de nombreuses analyses pour étudier ces séries temporelles. Nous avons aussi utilisé des méthodes plus classiques empruntées aux domaines de l'analyse numérique et de la turbulence. Cette études se décompose en 3 parties, et plusieurs annexes. Les matériels et méthodes sont présentés dans la première partie. Dans la seconde partie, la méthode EMD nous a permis de mettre en avant les fortes fluctuations contenues dans les blooms, ainsi que de mener des analyses spectrales grâce à un couplage avec la transformée de Hilbert. L'analyse en composante principale (ACP) a mis en avant les principaux forçages exercés sur la production primaire et les profils de température SOMLIT laissent supposer un impact de la stratification sur l'intensité des blooms. Dans la troisième partie, nous avons mené une étude comparative entre les données basses fréquences et hautes fréquences. Et deux méthodes de cross-corrélation (TDIC et co-spectre) nous ont permis de définir une échelle caractéristique de transition entre les températures de la Manche occidentale et orientale. En annexe, nous avons testé la robustesse de différentes méthodes d'analyses spectrales quant au manque de données dans les séries temporelles, qui est un problème inhérent aux bases de données enregistrées par des systèmes automatisés, et nous avons reproduit un article qui est en cours de soumission. / The main objective of this thesis is the characterization of high frequency dynamics in coastal areas and in particular their extremes, through the study of long-term biodeochemical time series registered by automated systems. The majority of high-frequency data sets used in this study came from MAREL program. The low-frequency time series from coastal monitoring programs SOMLIT (CNRS, INSU) and SRN (Ifremer) are employed to support the importance of automated systems. The EMD (Empirical Mode decomposition) method has provided a basis for us to study several of these time series. We also have used some methods more classical borrowed from numerical analysis field and turbulence. This study is organized in three chapters, and several appendices. The first chapter is devoted to the material and method. In the second chapter, using the EMD method we have highlighted the strong fluctuations contained in the blooms, and we have performed spectral analyzes. The principal component analysis (PCA) highlighted the main forcing exerted on primary production and SOMLIT temperature profiles suggest an impact of stratification on the intensity of blooms. In the third chapter, we conducted a comparative study between low-frequency and high-frequency data. Two cross-correlation methods (TDIC and co-spectra) allowed us to define a characteristic transition scale between the temperatures of the western and eastern English Cahnnel. In appendices we tested the robustness of different spectral analysis methods about the missing data in the time series, which is an underlying problem in the database registered by automated systems, and we reproduce a paper, which is under submission.

L’approximation dite « anélastique » permet de filtrer les ondes acoustiques grâce à un développement asymptotique deséquations de Navier-Stokes, réduisant ainsi le pas en temps moyen, lors de la simulation numérique du développement d’instabilités hydrodynamiques. Ainsi, les équations anélastiques sont établies pour un mélange de deux fluides pour l’instabilité de Rayleigh-Taylor. La stabilité linéaire de l’écoulement est étudiée pour la première fois pour des fluides parfaits, par la méthode des modes normaux, dans le cadre de l’approximation anélastique. Le problème de Stokes issu des équations de Navier-Stokes sans les termes non linéaires (une partie de la poussée d’Archiméde est prise en compte) est défini ; l’éllipticité est démontrée, l’étude des modes propres et l’invariance liée à la pression sont détaillés. La méthode d’Uzawa est étendue à l’anélastique en mettant en évidence le découplage des vitesses en 3D, le cas particulier k = 0 et les modes parasites de pression. Le passage au multidomaine a permis d’établir les conditions de raccord (raccord Co de la pression sans condition aux limites physiques). Les algorithmes et l’implantation dans le code AMENOPHIS sont validés par les comparaisons de l’opérateur d’Uzawa développé en Fortran et à l’aide de Mathematica. De plus des résultats numériques ont été comparés à une expérience avec des fluides incompressibles. Finalement, une étude des solutions numériques obtenues avec les options anélastique et compressible a été menée. L’étude de l’influence de la stratification initiale des deux fluides sur le développement de l’instabilité de Rayleigh-Taylor est amorcée. / The « anelastic » approximation allows us to filter the acoustic waves thanks to an asymptotic development of the Navier-Stokes equations, so increasing the averaged time step, during the numerical simulation of hydrodynamic instabilitiesdevelopment. So, the anelastic equations for a two fluid mixture in case of Rayleigh-Taylor instability are established.The linear stability of Rayleigh-Taylor flow is studied, for the first time, for perfect fluids in the anelastic approximation.We define the Stokes problem resulting from Navier-Stokes equations without the non linear terms (a part of the buoyancyis considered) ; the ellipticity is demonstrated, the eigenmodes and the invariance related to the pressure are detailed.The Uzawa’s method is extended to the anelastic approximation and shows the decoupling speeds in 3D, the particular casek = 0 and the spurius modes of pressure. Passing to multidomain allowed to establish the transmission conditions.The algorithms and the implementation in the existing program are validated by comparing the Uzawa’s operator inFortran and Mathematica langages, to an experiment with incompressible fluids and results from anelastic and compressiblenumerical simulations. The study of the influence of the initial stratification of both fluids on the development of the Rayleigh-Taylor instability is initiated.

Water from Mantua reservoir has, during some years, exhibited reddish-brown staining when used by Brigham City for irrigation. I propose that seasonal fluctuations in the reservoir chemistry create an environment conducive to dissolving iron from the iron-rich sediments, which subsequently precipitate during irrigation, resulting in a staining event. These conditions are produced by chemical and biological decomposition of organic matter, coupled with isolation of the hypolimnetic waters, which results in seasonal low concentrations of dissolved oxygen in these waters. Under these specific circumstances, anaerobic conditions develop creating a geochemical environment that causes iron and manganese reduction from Fe(III) to Fe(II) and Mn(IV) to Mn(II), respectively. These reducing conditions facilitate reduction-oxidation (redox) chemical reactions that convert insoluble forms of iron and manganese found in the reservoir sediments into more soluble forms. Consequently, relatively high amounts of dissolved iron and manganese are generated in the bottom waters immediately adjacent to the benthic sediments of the reservoir. Water withdrawn from a bottom intake pipe during these periods introduces iron-rich water into the distribution system. When this water is exposed to oxygen, reoxidation shifts redox equilibrium causing precipitation of soluble Fe(II) and Mn(III) back to highly insoluble Fe(III) and Mn(IV). The precipitant appears on contact surfaces as the aforementioned ferric stain. This research focuses specifically on the iron chemistry involved and evaluates this hypothesis using various measurements and models including field data collection, computer simulations, and bench-scale testing to validate the processes proposed.