Dissertations / Theses: 'Population active à la fin'

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Chen, Sina. "Probing the population of narrow-line Seyfert 1 galaxies with a southern hemisphere extended sampling." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3422848.

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During my Ph.D., I carried out a multi-wavelength study of narrow-line Seyfert 1 galaxies (NLS1s), with the aim of better understanding this peculiar class of AGN. I present a new accurately selected catalog of NLS1s in the southern hemisphere from the Six-degree Field Galaxy Survey (6dFGS) final data release. The classification was based on their optical spectral properties. I further derived for the first time their flux-calibrated spectra that are not provided by the 6dFGS. By analyzing these spectra, I obtained strong luminosity correlations between continuum and optical emission lines. The central black hole masses were estimated with methods based on the reverberation mapping, confirming that NLS1s indeed host a relatively low-mass black hole compared to broad-line Seyfert 1 galaxies (BLS1s). In addition, I present a detailed study of a limited number of NLS1s from the 6dFGS sample that both have optical and X-ray spectroscopic observations. There are five complex NLS1s (C-NLS1s) and six simple NLS1s (S-NLS1s). I propose a possible correlation between [O III] line asymmetry and X-ray complexity. The outflow or wind from the inner accretion disk is commonly present in NLS1s and mostly directed along the system axis. S-NLS1s are sources viewed at a small inclination, where the speed of the wind is high thus the blueshift of the blue wing is large. Such a strong wind could blow away the ionized material, therefore result in a simple X-ray spectrum. At a large inclination, instead, the speed of the wind is low, thus the blueshift is less prominent in C-NLS1s. The presence of ionized material in the weak wind could lead to the X-ray spectral complexity. A fraction of NLS1s are detected at radio frequency. I studied their radio properties at 1.4 GHz and 5 GHz using the NRAO VLA Sky Survey (NVSS) and the Karl G. Jansky Very Large Array (JVLA) respectively. Radio-loud (RL) sources tend to reside in the more distant universe, host a large massive black hole, and have a higher radio and optical luminosity compared to radio-quiet (RQ) sources. To extend the spectral coverage, I generated the test statistic (TS) maps for each radio-emitting source using the Fermi-LAT ten years data set, finding no gamma-ray NLS1 in the sample.

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Karadal, Fatih Mutlu. "Active Flutter Suppression Of A Smart Fin." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609830/index.pdf.

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This study presents the theoretical analysis of an active flutter suppression methodology applied to a smart fin. The smart fin consists of a cantilever aluminum plate-like structure with surface bonded piezoelectric (PZT, Lead- Zirconate-Titanate) patches. A thermal analogy method for the purpose of modeling of piezoelectric actuators in MSC&reg /NASTRAN based on the analogy between thermal strains and piezoelectric strains was presented. The results obtained by the thermal analogy were compared with the reference results and very good agreement was observed. The unsteady aerodynamic loads acting on the structure were calculated by using a linear two-dimensional Doublet-Lattice Method available in MSC&reg /NASTRAN. These aerodynamic loads were approximated as rational functions of the Laplace variable by using one of the aerodynamic approximation schemes, Roger&amp #8217 s approximation, with least-squares method. These approximated aerodynamic loads together with the structural matrices obtained by the finite element method were used to develop the aeroelastic equations of motion of the smart fin in state-space form. The Hinf robust controllers were then designed for the state-space aeroelastic model of the smart fin by considering both SISO (Single-Input Single-Output) and MIMO (Multi-Input Multi-Output) system models. The verification studies of the controllers showed satisfactory flutter suppression performance around the flutter point and a significant improvement in the flutter speed of the smart fin was also observed.

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Morin, Germain. "L'émigration au Saguenay : (fin XIXe - début XXe siecle) /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1991. http://theses.uqac.ca.

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Peroutka, Christopher Ryan. "Patient Reported Outcomes in a Physically Active Population." Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/28741.

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OBJECTIVE: To examine the efficacy of patient-reported outcome measures in the physically active and to determine whether a relationship exists between general health-related quality of life and specific outcome measures. Instruments used were the DPA, the SF-36, the QuickDASH, and the ASES. METHODS: 42 NCAA Division I athletes completed outcome measures three separate times. Repeated-measures ANOVA was performed and bivariate Pearson correlations were calculated. Additionally, test-retest reliability and minimal detectable change were assessed. Significance was set at ? ? 0.05. RESULTS: Significant relationships were found between the DPA and several subscales of the SF-36. Participation in physical activity did not have an effect on scores as measured at different time points. CONCLUSIONS: The DPA and SF-36 are effective measures of health in physically active populations. The QuickDASH and ASES may not be reliable measures in these populations. North Dakota State University. Advanced Athletic Training program

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Tan, Bee San Fleckenstein Lawrence L. "Population pharmacokinetics of artesunate and its active metabolite dihydroartemisinin." [Iowa City, Iowa] : University of Iowa, 2009. http://ir.uiowa.edu/etd/442.

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Inan, Ceren. "Dynamique démographique de la population active occupée en France." Phd thesis, Université Montesquieu - Bordeaux IV, 2009. http://tel.archives-ouvertes.fr/tel-00814734.

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Cette thèse se propose d'analyser les phénomènes concourrant à la dynamique de la population active occupée. Après avoir dressé un large tableau rétrospectif de l'évolution des taux d'emploi au fil des périodes et des générations, elle se fonde sur les enquêtes Emploi plus récentes (1968 - 2007) et sur l'enquête " Etude de l'histoire familiale " de 1999 pour approfondir la décomposition des facteurs démographiques déterminant les tendances de l'emploi. L'évolution du temps de travail hebdomadaire, celle des calendriers d'entrées et de sorties de la vie professionnelle et le mouvement des interruptions temporaires de l'occupation professionnelle sont ainsi introduits dans l'analyse. La prise en compte de ces éléments de désagrégation conduit à remarquer une plus grande concentration de l'occupation professionnelle dans la vie des individus, de 1968 jusqu'au milieu des année 1990, sous l'influence d'un retard de l'entrée dans le premier emploi et de sorties définitives de la vie active occupée plus précoces, double tendance qui s'estompe depuis le milieu des année 1990. A cela s'ajoute, depuis le début des années 1970, la hausse des taux d'emploi des femmes d'âges intermédiaires, sous la conjonction de trois facteurs : la baisse de la proportion des femmes n'ayant jamais travaillé, la baisse des sorties définitives de l'occupation professionnelle avant 50 ans, et la réduction du poids des interruptions passagères de la vie professionnelle. L'ensemble de ces évolutions correspond à un très fort renouvellement démographique de l'emploi, avec des taux bruts d'entrée et de sortie qui dépassent largement les 10% mais qui, vu les tendances précédemment évoquées, n'engendrent qu'une croissance modérée de la population active occupée, inférieure à celle de la population en âge de travailler.

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Tan, Bee San. "Population pharmacokinetics of artesunate and its active metabolite dihydroartemisinin." Diss., University of Iowa, 2009. https://ir.uiowa.edu/etd/442.

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Artemisinin compounds are the most potent anti-malarial drugs available in the market. Today, malaria treatment is largely relies on the artemisinin-based combination therapies. Artesunate (AS) is the most widely used artemisinin derivative. In this thesis, we characterized the population pharmacokinetics of AS and its active metabolite dihydroartemisinin (DHA) following oral administration of AS in different populations. In Chapter II, we developed a population pharmacokinetic model of AS and DHA in healthy subjects. These subjects received either single- or multiple-dosing of oral AS, as a monotherapy regimen or in combination with pyronaridine, with or without food. In Chapter III, we developed a population pharmacokinetic model of AS and DHA in adult and pediatric patients with uncomplicated falciparum and vivax malaria who were administered oral pyronaridine/artesunate combination once daily for 3 days. We modeled the AS and DHA data simultaneously using a parent-metabolite model that assumed complete conversion of AS to DHA. Following oral administration, AS is rapidly absorbed with maximum concentrations reached at about 0.5 hours post-dose. AS is rapidly converted to DHA. DHA then undergoes rapid metabolism, with an elimination half-life of about 0.8 hours in malarial patients. Inter-individual variability for almost all pharmacokinetic parameters and residual variability for both compounds were estimated by the models. Substantial variability was seen in the pharmacokinetic parameters between the subjects. In healthy subjects, intake of food with the dose was found to delay the absorption of AS significantly, but not the extent of absorption. Weight was also included in this model as a determinant of DHA clearance. When modeling the data from patients, we included weight as part of the model a prioria priori using an established allometric function. No other covariates examined in the analysis were statistically significant. The performance of final models was evaluated using non-parametric bootstrap technique and visual predictive check. The models were found to adequately described the data at hand, and robust with sufficient predictive power. The results can be used as the base to develop a population pharmacokinetic-pharmacodynamic model and as prior information in guiding the selection of optimal sampling schedule for future pharmacokinetic studies of AS.

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Jourdan, Virginie. "Pauvreté de la population active en France : Définitions, caractéristiques, dynamique." Phd thesis, Université Montesquieu - Bordeaux IV, 2009. http://tel.archives-ouvertes.fr/tel-00458350.

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En France, en 2005, le taux de pauvreté s'élevait à 9,6 % de la population active selon la définition de la pauvreté relative de l'Insee, soit 2,6 millions d'actifs pauvres. Le taux de pauvreté renseigne bien sur une proportion d'actifs pauvres à un moment donné, mais n'informe pas sur les mouvements d'entrées dans la pauvreté et de sorties de la pauvreté de la population active. Les outils de l'analyse démographique permettent une analyse longitudinale de ces phénomènes. Dans le cadre de ce travail, nous répondrons aux deux questions suivantes : - parmi les actifs ayant vécu, au cours d'une même période, l'entrée dans la pauvreté, quelle est la proportion de ceux qui sortent de la pauvreté ? - parmi les actifs ayant vécu, au cours d'une même période, la sortie de la pauvreté, quelle est la proportion de ceux qui retournent dans la pauvreté ? La définition de la pauvreté relative mesure en réalité un changement de position du ménage sur l'échelle des revenus et non une modification effective du niveau de vie. Dans ce cas, la définition de la pauvreté absolue que nous proposons paraît donc plus adaptée pour une étude longitudinale de la pauvreté. Parmi les actifs pauvres, 7 sur 10 travaillent. Bien que l'emploi protège de la pauvreté, il n'est pas une protection suffisante. La situation familiale est aussi un facteur à prendre en compte. Finalement, les risques de sortie de la pauvreté et les risques d'entrée dans la pauvreté dépendent des caractéristiques individuelles de la personne active mais se modifient également lorsque la personne active connaît un changement favorable ou défavorable de sa situation sur le marché du travail ou de sa situation familiale.

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9

Abu-Amer, Nabil Mohamed. "Biomarkers of active and latent TB in a Brazilian population." Thesis, University of Liverpool, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.507581.

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10

Jourdan, Viriginie. "Pauvreté de la population active en France : définitions, caractéristiques, dynamique." Bordeaux 4, 2009. http://www.theses.fr/2009BOR40061.

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En France, en 2005, le taux de pauvreté s'élevait à 9,6 % de la population active selon la définition de la pauvreté de l'Insee, soit 2,6 millions d'actifs pauvres. Le taux de pauvreté renseigne bien sur une proportion d'actifs pauvres à un moment donné, mais n'informe pas sur les mouvements d'entrée dans la pauvreté et de sortie de la pauvreté de la population acrive. Les outils de l'analyse démographique permettent une analyse longitudinale de ces phénomènes. Dans le cadre de ce travail, nous répondrons aux deux questions suivantes : - parmi les actifs ayant vécu au cours d'une même période, l'entrée dans la pauvreté, quelle est la proportion de ceux qui sortent de la pauvreté ? - parmi les actifs ayant vécu, au cours d'une même période, la sortie de la pauvreté, quelle est la proportion de ceux qui retournent dans la pauvreté ? La définition de la pauvreté relative mesure en réalité un changement de position du ménage sur l'échelle des revenus et non une modification effective du niveau de vie. Dans ce cas, la définition de la pauvreté absplue que nous proposons paraît plus adaptée pour une étude longitudinale de la pauvreté. Parmi les actifs pauvres, 7 sur 10 travaillent. Bien que l'emploi protège de la pauvreté, il n'est pas une protection suffisante. La situation familiale est aussi un facteur à prendre en compte. Finalement, les risques de sortie de la pauvreté et les risques d'entrée dans la pauvreté dépendent des caractéristiques individuelles de la personne active mais se modifie également lorsque la personne active connaît un changement favorable ou défavorable de sa situation sur le marché du travail ou de sa situation familiale In France, in 2005, the poverty rate rose at 9. 6 % of the active population according to the Insee's definition of the relative poverty, i. E. 2. 6 millions of poor active persons. The poverty rate informs rightly the proportion of poor active persons at a given date, but doesn't inform about the active population inflows into the poverty and outflows outside the poverty. Demographic analysis tools allow bringing a longitudinal analysis of these phenomena. Throughout this work, we will answer to the following two questions : - among the active persons having lived, during the same period, the inflow into the poverty, what is the proportion of those which have left the poverty ? - among the active persons having lived, during the same period, the outflow outside the poverty, what is the proportion of those which have entered again into the poverty ? In fact, the relative poverty definition measure a change into the household's position on the incomes scale, and not a real change regarding the standard of living. In that case, the absolute poverty definition which we suggest seems more appropriate for a longitudinal study about the poverty. 7 persons per 10 actually work among the poor active persons. Even if employment protects against poverty, it's not a sufficient protection. The family situation is also a factor to take in account. Eventually, risks of outflows outside the poverty and risks of inflows into the poverty depend of the active person's individual characteristics but also modify outflow when the active person knows a favourable of unfavourable change regarding his/her situation in the labour market or family situation

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Campbell, Jon Bradley. "Improving muscular strength and balance in an older active population /." View online, 1994. http://repository.eiu.edu/theses/docs/32211998858820.pdf.

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12

Morris, Denise Nichole. "Population pharmacokinetics of telapristone and its active metabolite CDB-4453." Diss., University of Iowa, 2011. https://ir.uiowa.edu/etd/1034.

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In this thesis, the population pharmacokinetics of telapristone and its active metabolite, CDB-4453 was evaluated using nonlinear mixed effects modeling (NONMEM®). A two-compartment (parent) one compartment (metabolite) mixture model with first order absorption and elimination adequately described the pharmacokinetics of telapristone and CDB-4453. For the Phase I/II pharmacokinetic analysis (effect of renal and hepatic impairment), telapristone was rapidly absorbed with an absorption rate constant (Ka) of 1.26 h-1. Moderate renal impairment resulted in a 74% decrease in Ka. Population estimates for oral clearance (CL/F) for the high and low clearance groups were 11.6 L/h and 3.34 L/h, respectively. Twenty-five percent of the subjects were allocated to the high clearance group. Apparent volume of distribution for the central compartment (V2/F) was 37.4 L, apparent inter-compartmental clearance (Q/F) was 21.9 L/h, and apparent peripheral volume of distribution for the parent (V4/F) was 120 L. The ratio of the fraction of telapristone converted to CDB-4453 to the distribution volume of CDB-4453 (Fmetest) was 0.20/L and apparent clearance of the metabolite (CLM/F) was 2.43 L/h. For the pharmacokinetic analysis evaluating the effect of food; food decreased the Ka of telapristone (Ka for the fed and fasted state was 0.467 and 5.06 h-1, respectively). Population estimates of the high and low CL/F groups were 12.0 L/h and 3.15 L/h, respectively. Thirty-one percent of the subjects were allocated to the high clearance group. V2/F, Q/F and V/4 and Fmetest were 52.8 L, 7.53 L/h, 84.8 L and 0.193/L, respectively. CLM/F was 2.10 L/h. An external validation was performed using the final parameter estimates from the pooled pharmacokinetic analysis (effect of renal and hepatic impairment and the effect of food). From this pharmacokinetic analysis, Ka for the fed and fasted state was 0.299 and 2.35 h-1, respectively. Population estimates for the high and low CL/F groups were 11.6 L/h and 3.22 L/h, respectively. The percentage of subjects allocated to the high clearance group was 29%. V2/F, Q/F, V/4 and Fmetest were 52.8 L, 11.6 L/h and 93.8 L and 0.186/L, respectively. CLM/F was 2.23 L/h. The final model did not meet the requirement for adequate predictability using the external validation dataset. However, the external validation dataset only included samples with limited early time points. Because of the limited sampling times, it is difficult to make a conclusion about the overall adequacy of the model. An external validation dataset with more extensive sampling will be needed in order to better assess the predictability final model. This is the first comprehensive review of the pharmacokinetics of telapristone and CDB-4453.

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Shuval, Tal. "La ville d'Alger vers la fin du XVIIIe siècle : population et cadre urbain." Aix-Marseille 1, 1994. http://www.theses.fr/1994AIX10063.

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A partir principalement de documents des archives d'alger (inventaires apres deces du bayt al-mal, actes de habus) dont les microfilms se trouvent aux archives d'outre-mer a aix-en-provence, se dessine une image de la societe d'alger et de ses composantes au cours du xviiie siecle. Apres une etude demographique de la population, la hierarchie de la milice turque (ugak) et ses activites sont analyses. La marine corsaire et la course maritime sont egalement etudiees. On procede ensuite a une analyse des residences des janissaires (dans les casernes et en ville) et de leurs etat-civil ainsi qu'a l'etude du groupe des fils de militaires et de femmes indigenes (kulugli). Les differentes composantes de la population civile, leur residence et leurs diverses activites economiques (commerce, artisanat etc) et la participation des femmes dans cette activite sont egalement etudiees. L'etude des actes de habus (dotations pieuses) permet de dessiner la situation de la ville qui sert le cadre a la population, avec ses fortifications et son port. On y voit apparaitre deux parties distinctes: la ville basse, zone publique qui abrite les centres administratifs, economiques et religieux, et la ville haute, zone a destination residentielle, ou se trouvaient principalement les quartiers avec leurs equipements. La repartition de la population suivant sa richesse dans les differentes parties de la ville est egalement decrite The study of archive documents (principaly) probate inventories of the bayt al-mal and waaf titles), being kepts as microfilms in the archives d'outre mer in aix-en-provence, helps drowing an image of the city of algiers and the various components of its society during the 18th century. A demographic study of the population is followed by an analysis of the hierarchical order of the tukish milicia (ugak) and of its activities, such as tax collection (mahalla). Navy and privateering are being studied too. Residences of the janissaires (in the barracks and in town) and their civil status analysis is being followed by a study of the group of the sons of turkish soldiers and local women (kulugli). Different components of civil population including black slaves, are studied as well as their economic activities (trade, crafts. . . ), and women's participation in those activities lodging of the civil population is being studied too. The study of waaf (religious foundations) deeds reveals the situation of the city with its fortifications and its harbour, which serves as a framework for all that population. Two separate sections appear : "downtown", public area where the administrative, economic and religious centers are situated, and "uptown", where residential quarters with their daily life equipments are to be found. The distribution of the population, in the different areas of the city, according to its richness is also being described

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Kokubu, Hisao. "L'impact du réseau de tramways sur la population marseillaise (fin XIXème-début XXème)." Thesis, Aix-Marseille 1, 2011. http://www.theses.fr/2011AIX10068.

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La période entre 1872 et 1931 correspondait à la phase maximale de l’urbanisation en France avant la Seconde Guerre mondiale. Les tramways jouaient un rôle décisif pour développer les banlieues. À Marseille, le premier maire socialiste Siméon Flaissières débuta dès le 1er janvier 1900 une politique du transport public urbain, introduisant l’électrification du réseau de tramways et surtout « les Tramways à dix centimes ». Le maire républicain et anti-collectiviste Amable Chanot prolongea ensuite des lignes du réseau, notamment vers les banlieues agricoles, sous la pression de l’opinion publique. L’installation du réseau de tramways dans les banlieues a influé sur le choix du domicile et le travail des individus et des familles. Jusqu’aux années 1920, les tramways étaient indispensables à la vie d’une grande ville The period between 1872 and 1931 was the time of greatest urbanization in France before the Second World War. The tramways played a determining role in the development of suburban residential areas. In Marseilles, from the 1st of January 1900, the first socialist Mayor, Siméon Flaissières instigated a policy of urban public transport, introducing the electrification of the tramway network, and most importantly, « The 10 Centimes Tramway » system. Giving in to the pressure of public opinion, the republican and anti-collectivist Mayor, Amable Chanot, later extended the network, especially towards the rural suburbs. The implementation of the suburban tramway network influenced the choices of places of residence and work of individuals and families alike. Up until the 1920’s, the tramways were an indispensable part of life in a big city

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Palsson, Halldor Petur Carleton University Dissertation Economics. "Population dynamics and extinction: an application to the Fin Whale stock off Iceland." Ottawa, 1991.

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Shuval, Tal. "La ville d'Alger vers la fin du XVIIIe siècle : population et cadre urbain /." Paris : CNRS éd, 1998. http://catalogue.bnf.fr/ark:/12148/cb37031858q.

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Monette, Josée. "La transformation de la population active des différents secteurs d'activités économiques au Canada : 1961 a 1981 /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1993. http://theses.uqac.ca.

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THIEU, THI KIM THOA. "Models for coupled active--passive population dynamics: mathematical analysis and simulation." Doctoral thesis, Gran Sasso Science Institute, 2020. http://hdl.handle.net/20.500.12571/15016.

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In this dissertation, we study models for coupled active--passive pedestrian dynamics from mathematical analysis and simulation perspectives. The general aim is to contribute to a better understanding of complex pedestrian flows. This work comes in three main parts, in which we adopt distinct perspectives and conceptually different tools from lattice gas models, partial differential equations, and stochastic differential equations, respectively. In part one, we introduce two lattice models for active--passive pedestrian dynamics. In a first model, using descriptions based on the simple exclusion process, we study the dynamics of pedestrian escape from an obscure room in a lattice domain with two species of particles (pedestrians). The main observable is the evacuation time as a function of the parameters caracterizing the motion of the active pedestrians. Our Monte Carlo simulation results show that the presence of the active pedestrians can favor the evacuation of the passive ones. We interpret this phenomenon as a discrete space counterpart of the so-called drafting effect. In a second model, we consider again a microscopic approach based on a modification of the simple exclusion process formulated for active--passive populations of interacting pedestrians. The model describes a scenario where pedestrians are walking in a built environment and enter a room from two opposite sides. For such counterflow situation, we have found out that the motion of active particles improves the outgoing current of the passive particles. In part two, we study a fluid-like driven system modeling active--passive pedestrian dynamics in a heterogenous domain. We prove the well-posedness of a nonlinear coupled parabolic system that models the evolution of the complex pedestrian flow by using special energy estimates, a Schauder's fixed point argument and the properties of the nonlinearity's structure. In the third part, we describe via a coupled nonlinear system of Skorohod-like stochastic differential equations the dynamics of active--passive pedestrians dynamics through a heterogenous domain in the presence of fire and smoke. We prove the existence and uniqueness of strong solutions to our model when reflecting boundary conditions are imposed on the boundaries. To achieve this we used compactness methods and the Skorohod's representation of solutions to SDEs posed in bounded domains. Furthermore, we study an homogenization setting for a toy model (a semi-linear elliptic equation) where later on our pedestrian models can be studied.

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Ballero, Silvia Kuna. "Evolution of chemical abundances in active and quiescent spiral bulges." Doctoral thesis, Università degli studi di Trieste, 2008. http://hdl.handle.net/10077/2560.

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2006/2007 In this thesis I develop a chemical evolution model which takes advantage of the most recent high-quality abundance observations in the Galactic bulge to put constraints on its formation and evolution and to obtain a baseline model for bulges in general. I adopt updated massive star nucleosynthesis and follow the evolution of several alpha-elements and Fe by varying the evolutionary parameters. The [alpha/Fe] ratios in the bulge are correctly predicted to be supersolar for a wide range in [Fe/H], and the stellar metallicity distribution is reproduced assuming a short formation timescale, a high star formation efficiency and an initial mass function flatter than the disk. Metallicity-dependent oxygen yields with stellar mass loss are included in the chemical evolution models for the bulge and the solar neighbourhood. The agreement between predicted and observed [O/Mg] trends above solar metallicity is significantly improved; a normalisation problem probably indicates that the adopted semi-empirical yields need adjustment. The difference between [O/Fe] and the other [alpha/Fe] ratios in the bulge and solar neighbourhood is explained. I test the so-called universal initial mass function, suitable for ellipticals and disks, to see if the bulge stellar metallicity distribution can be reproduced by varying the yields for very massive stars, and included M31 in my analysis. I show that assuming a flatter initial mass function than the universal one is necessary, and that a variation exists in the initial mass function among different environments. Finally, I investigate the evolution of spiral bulges hosting Seyfert nuclei, with detailed calculations of the galactic potential and of the feedback from the central supermassive black hole in an Eddington-limited accretion regime. New spectro-photometrical evolution codes covering a wide range of stellar ages and metallicities allowed to model the photometric features of local bulges. I successfully predict the observed black hole-host bulge mass relation. The observed present-day nuclear bolometric luminosity is achieved only for the most massive bulges, otherwise a rejuvenation is necessary. The observed high star formation rates and metallicities, constancy of chemical abundances with the redshift and bulge present-day colours are reproduced, but a steeper initial mass function is required to match the colour-magnitude relation and the present K-band bulge luminosity. In questa tesi, ho sviluppato un modello di evoluzione chimica che si avvale di recenti osservazioni ad alta qualità di abbondanze chimiche nel bulbo della Via Lattea, per porre dei vincoli sui suoi meccanismi di formazione ed evoluzione e ottenere un modello generale per i bulbi di spirale. Ho adottato una nucleosintesi aggiornata per le stelle massicce e seguito l'evoluzione di diversi elementi-alpha e del ferro, variando i parametri evolutivi. Si prevede correttamente che i rapporti [alpha/Fe] nel bulbo siano soprasolari per un ampio intervallo in [Fe/H]. La distribuzione in metallicità è riprodotta con un tempo di formazione breve, un'alta efficienza di formazione stellare e una funzione iniziale di massa più piatta che nel disco. Yields di ossigeno con perdita di massa stellare in funzione della metallicità sono stati inclusi nei modelli di evoluzione chimica del bulbo e dei dintorni solari. L'accordo tra gli andamenti di [O/Mg] previsti e osservati per metallicità soprasolari risulta sensibilmente migliorato; si spiega inoltre la differenza tra il rapporto [O/Fe] e gli altri [alpha/Fe] nel bulbo e nei dintorni solari. Un problema di normalizzazione indica che probabilmente gli yields semi-empirici adottati necessitano una revisione. Ho verificato se con la cosiddetta funzione iniziale di massa universale, adeguata per galassie ellittiche e dischi, la distribuzione in metallicità stellare del bulge può essere riprodotta calibrando gli yields delle stelle supermassicce, includendo M31 nell'analisi. Si dimostra che una funzione iniziale di massa più piatta di quella universale è necessaria, e che esiste una variazione nella funzione iniziale di massa tra i diversi ambienti. Infine, ho studiato l'evoluzione di bulbi di spirali che ospitano galassie di Seyfert, mediante calcoli dettagliati del potenziale galattico e del feedback dal buco nero supermassiccio centrale in un regime di accrescimento limitato dal tasso di Eddington. Nuovi codici spettro-fotometrici che coprono un ampio intervallo di età stellari e di metallicità hanno permesso di modellizzare le caratteristiche fotometriche dei bulbi locali. La relazione osservata tra massa del buco nero e del bulbo ospite è prevista con successo. La luminosità bolometrica nucleare misurata al tempo presente si consegue solo per i bulbi più massicci, negli altri casi è necessario un "ringiovanimento". Le osservazioni di alto tasso di formazione stellare, alte metallicità, invarianza di abbondanze chimiche col redshift e colori dei bulbi locali sono riprodotte; una funzione iniziale di massa più ripida è invece richiesta per la relazione colore-magnitudo e la luminosità dei bulbi in banda K al tempo presente. XX Ciclo 1979

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Balta, Evangelia. "L'Eubée à la fin du XVe siècle : économie et population : les registres de l'année 1474 /." Athènes : 'Etaireia euboïkōn spoudōn, 1989. http://catalogue.bnf.fr/ark:/12148/cb36666666h.

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Texte remanié de: Th. 3e cycle--Paris 1, 1983. Titre de soutenance : L'île d'Eubée à la fin du XVe siècle d'après les registres n ° 0.73 de la bibliothèque Cevdet à Istanbul. Nom d'éditeur et titre de collection translittérés du grec selon ISO R/843 (1968). Contient le fac-sim. des registres en turc ottoman avec leur transcription en caractères latins et leur trad. française. Résumé en grec. Bibliogr. p. 173-188. Index.

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Hazotte, Claire. "Traitement de la matière active d’accumulateurs Ni-Cd en fin de vie par couplage électrolixiviation/électrodéposition." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0238/document.

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Ce mémoire porte sur le développement d'un protocole d'extraction sélective de métaux présents dans les accumulateurs Ni-Cd en fin de vie. Classiquement, les procédés hydrométallurgiques appliqués à ce type de solides comportent de nombreuses étapes dont les principales sont la lixiviation et la récupération du métal par électrolyse. Le procédé utilisé permet le couplage des opérations d'Electrolixiviation et d'Electrodéposition (noté E/E) au sein d'une même cellule. La technique est basée sur la lixiviation de la matière active des accumulateurs Ni-Cd par les protons générés à l'anode, les cations lixiviés (Co2+, Ni2+ et Cd2+) migrent vers la cathode où le cadmium est sélectivement réduit. Nous avons étudié les possibilités de récupération des métaux, mais également tenté d'appréhender les phénomènes prenant place dans la cellule lors du couplage E/E. Dans un premier temps, nous avons choisi de démanteler manuellement des accumulateurs en raison de la complexité des broyats industriels. La matière active des accumulateurs Ni-Cd a été caractérisée. Sa composition moyenne est la suivante :Cd(OH)2 : 45,3 %, Cd0 : 0,02 %, Ni(OH)2 : 30,0 %, Ni0 :12,9 %, NiOOH : 0,9%, Co(OH)2 : 2,4 %. Au vu des différentes formes minéralogiques présentes, ce solide peut être considéré comme un déchet modèle pour ce traitement. Avant d'envisager le couplage E/E, la lixiviation chimique de la matière active par H2SO4 a d'abord été étudiée. La modélisation de cette opération a mis en évidence que la cinétique de dissolution de Cd(OH)2 est gouvernée par le transfert de masse des protons, la dissolution de Ni(OH)2 et Co(OH)2 étant quant à elle régie par la réaction chimique de surface. Dans ces conditions de lixiviation douce, le nickel métallique n'est pas oxydé et se retrouve dans le résidu solide avec le carbone. Nous avons pu démontrer ensuite la sélectivité de l'électrodéposition vis-à-vis du Co2+ et du Ni2+ avec un rendement faradique d'environ 99 % à une densité de courant de 350 A.m-2. L'étude cinétique de l'E/E a montré que l'électrolixiviation est l'étape limitante du procédé, phénomène qui a également été modélisé. L'E/E appliquée aux matériaux d'électrodes permet en 5 h 30 de lixivier 97 % du cadmium initialement présent. Le solide résiduel est composé à 82 % de nickel, principalement sous la forme métallique, 4 % de cadmium, 0,5 % de cobalt et 3 % de carbone. Le dépôt de cadmium est obtenu avec une pureté supérieure à 97 % et un rendement faradique de déposition supérieur à 74 % à une densité de courant de 350 A.m-2. La faisabilité du couplage E/E appliqué au traitement d'accumulateurs Ni-Cd en fin de vie a été démontrée malgré la complexité de la matrice. Les premiers essais d'application de ce traitement à des échantillons industriels (Cd(OH)2 : 36,1 %, Ni(OH)2 : 24,1 %, Ni0 : 16,6 %, NiOOH : 5,5 %, Co(OH)2 : 2,4 % et Fe :1% en masse) confirment les résultats obtenus avec les matériaux d'électrodes provenant du démantèlement manuel This thesis focuses on the development of a protocol for selective extraction of metals from spent Ni-Cd batteries. Conventionally, hydrometallurgical processes applied to this type of solids involve several steps, the main ones being the leaching and the metal recovery by electrolysis. The method used consists in coupling Electroleaching to Electrodeposition operation (denoted E/E) within the same cell. The technique is based on the leaching of the active material of Ni-Cd batteries by protons generated at the anode: the cations (Co2+, Ni2+ and Cd2+) released by leaching migrate to the cathode where the cadmium is selectively reduced. We studied the possibility of metals recovery, but also tried to understand the phenomena occurring in the cell during the E/E experiments. Initially, it was preferred to manually dismantle batteries due to the complexity of industrial waste crushed. The active matter of Ni-Cd has been characterized. Its average composition is as follows: Cd(OH)2: 45.3%, Cd0: 0.02%, Ni(OH)2: 30.0%, Ni0: 12.9%, NiOOH: 0.9%, Co(OH)2: 2.4%. In view of these different mineralogical forms, this solid can be considered a model for the waste treatment. Before considering the E/E treatment, chemical leaching of the active matter by H2SO4 was first studied. Modelling of the tests carried out showed that the kinetics of Cd(OH)2 dissolution is governed by mass transfer of protons and the dissolution of Ni(OH)2 and Co(OH)2 by the surface chemical reaction. Under these conditions of soft leaching, metal nickel is not oxidized and is found in the solid residue, with carbon. We had to demonstrate the cadmium electrowinning selectivity, for separation from Co2+ and Ni2+ species, with a current efficiency up to 99% at a current density of 350 A.m-2. The kinetic study of the E/E showed that electroleaching is mainly governed by H+ generation at the anode. Besides, the overall process is largerly controlled by cations transport from the anode to the cathode side: this transport phenomenon had also been modeled. The E/E applied to the electrode materials for 5 h 30 allows the leaching of 97% of the cadmium initially present. The residual solid is composed by 82% of nickel, mainly in the metallic form, 4% of cadmium, 0.5% of cobalt and 3% carbon. The deposition of cadmium is obtained with a purity greater than 97% and a current efficiency greater than 74% at a current density of 350 A.m-2. The feasibility of the E/E coupling applied to the spent Ni-Cd batteries treatment has been demonstrated despite the complexity of the matrix. The first tests to apply this treatment to industrial samples (Cd(OH)2: 36.1% Ni(OH)2: 24.1% Ni0: 16.6% NiOOH: 5.5% Co(OH)2: 2.4% and Fe: 1% by weight) confirm the results obtained with the electrode material from the manual dismantling

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Laplante, Marie-Christine. "La dignité en fin de vie : application du construit chez une population en perte d'autonomie fonctionnelle." Doctoral thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/26366.

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Au Québec, le changement démographique en cours mène à l’augmentation du nombre de personnes âgées en perte d’autonomie fonctionnelle (PPAF). La relation du niveau de bien-être psychologique et de l’état de santé physique étant bien documentée, une considération pour la détresse d’ordres psychologique et spirituelle se manifeste dans la littérature et dans les milieux cliniques. Dans le modèle de la dignité, Chochinov et coll. (2006) ont proposé une série de variables qui affectent le sentiment de dignité des personnes en fin de vie. La présente étude vise à évaluer si les PPAF qui résident toujours à domicile souffrent également d’une diminution du sentiment de dignité et si les facteurs qui l’influencent s’apparentent ou se distinguent de ceux impliqués dans le sentiment de dignité des personnes en fin de vie. Les résultats obtenus n’indiquent aucune corrélation de forte intensité entre les variables indépendantes et le sentiment de dignité chez les 60 participants recrutés. Enfin, les résultats de la régression linéaire multiple révèlent que seule la variable de l'âge est statistiquement significative à un seuil de p≤=0.05 (p=0.029), à un Beta=0

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Blankenship, Neeta Serena, and Kristin M. Shepherd. "Analysis of suicide behaviors in the Navy active duty and reserve component population." Thesis, Monterey, California: Naval Postgraduate School, 2015. http://hdl.handle.net/10945/45162.

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Approved for public release; distribution is unlimited We analyze the role of service-specific and mental health risk factors in active duty and reserve component Navy enlisted and officer suicide attempts and deaths from 2002 to 2011. We estimate the effect of non-demographic, service-specific, pre-screening, and mental health factors through logit regression to determine their association with the occurrence of suicide attempts and death by suicide. We further evaluate how these risk factors differ between the active duty and reserve components. Results consistently found that diagnosed mental health conditions, specifically, depression and substance use, increased the odds of Sailors in all populations attempting and/or dying by suicide. Service-specific factors showed varying levels of significance across the different populations; however, those who were demoted and entry-level paygrades (E1-E4) in the enlisted population were at higher risk for suicide attempt and death. Deployment to a combat zone was associated with lower odds of attempting and dying by suicide for all populations except enlisted reservists. There were few significant covariates of suicide attempts or death among the officer population. The identification of common risk factors will aid in identifying service-wide efforts to determine the highest risk populations and develop tailored prevention programs.

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Vlasyk, L. Yu. "The behavioral risk factors of major non-communicable diseases among economically active population." Thesis, БДМУ, 2020. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/18309.

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Demers, Daniel. "L'intégration des opposés en fin de carrière: évolution en lien avec le profil de Holland et l'androgynie." Sherbrooke : Université de Sherbrooke, 2001.

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Tamaro-Hans, Annick. "Incidence des événemements de vie sur les activités et la consommation : application au départ à la retraite." Paris 9, 2005. https://portail.bu.dauphine.fr/fileviewer/index.php?doc=2005PA090038.

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Les événements de vie impliquent une adaptation individuelle forte. La retraite est choisie dans cette recherche pour examiner les modifications en termes de pratiques d'activités et de consommation. Une revue de la littérature pluridisciplinaire (sociologie, psychologie, marketing), ainsi que des études exploratoires complémentaires, mettent en évidence la notion centrale de " vécu de la retraite " et ses principaux déterminants (investissement professionnel, rapport au temps, valeurs, satisfaction globale, ressources). Une étude quantitative permet ensuite d'en identifier les différentes formes (" nouvelle vie ", " retrait ", " repos ", " continuité "), cohérentes avec les théories psychosociales du vieillissement. Elle conduit également à décrire les activités et consommations afférentes à chacune de ces formes qui apparaissent alors comme autant de critères de segmentation Life events require adjustments. In this research, retirement is viewed as a critical life event which may involve a change in activities and in consumption patterns. Based on research from different scientific disciplines (sociology, psychology, marketing) and former studies, this research stresses the subjective experience of retirement which has four modes (“new beginning”, “withdrawal”, “rest”, “continuity”) and develops a conceptual model involving determinants (job involvement, perception of time, values, global satisfaction, resources), activities and consumption. The results indicate that subjective experience of retirement is a significant predictor of activity level and consumer behaviour. The life stage of “retirement” is suggested as a segmentation variable

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Ipari, Marcel. "Les populations de la région de Sibiti (Congo) : du XVème à la fin du XIXème siècle." Paris 1, 1988. http://www.theses.fr/1988PA010525.

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La region de sibiti est designee comme etant le pays des bayaka qui se disent eux-memes bayaa (des yaa). L'historiographie classique a rendu tristement celebre cette population en lui trouvant une filiation tout a fait imaginaire avec les "jagas", ce peuple mythique qui aurait envahi l'ancien royaume de kongo vers la fin du 16e siecle. Nous tentons de montrer ici qu'a cette epoque les yaa de sibiti semblent deja etablis dans leur habitat actuel puisqu'ils sont les acteurs principaux du commerce de traite qui se developpe a partir de cette meme fin du 16e siecle. Cette activite les met en contact avec les riverains de la lilaali (haute-bouenza, a l'origine) : les balaali qui descendent alors progressivement vers le centre du pays yaa. A la fin du 19e siecle une autre population, venue du nord, les bambamba ou ambama, prennent egalement place dans la region de sibiti.

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Abell, Nicholas. "Population Demographics, Connectivity, and Recruitment Sources of Spotted Bass in Smithland Pool of the Ohio River." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/theses/2224.

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Understanding spatial patterns in population demographics and the principal natal environments supporting riverine fish populations are important for fisheries management. Although the black basses are among the most popular groups of game fishes in North America, relatively little information exists regarding demographics and environmental history of spotted bass Micropterus punctulatus in riverine environments. Fin ray microchemistry was used to identify natal environment and age estimates from sectioned fin rays used to estimate growth and mortality rates for spotted bass in Smithland pool of the Ohio River and three tributaries. Spotted bass were collected from 2014-2016 in headwater reaches of tributaries using electrofishing, angling, and a seine net, while electrofishing was used exclusively in the Ohio River and lower tributary reaches. Spotted bass in the Ohio River generally lived longer and grew larger than conspecifics in tributaries, although mortality rates were not definitively different. Differences in water Sr:Ca and Ba:Ca among the Ohio River and tributaries were reflected in fin rays from age-0 and age-1 fish. Eighteen percent of spotted bass ≥ age-2 captured in the Ohio River originated in tributaries, whereas 15% captured in tributaries originated in the Ohio River. Although most fish remained in their natal environment, small tributaries can be a supplemental recruitment source for spotted bass populations and fisheries in large rivers. This study highlights the utility of fin rays for microchemical analysis and age estimation of spotted bass.

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Lansbury, George Benjamin. "A hard X-ray view of the distant active galactic nucleus population with NuSTAR." Thesis, Durham University, 2016. http://etheses.dur.ac.uk/11901/.

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Active galactic nuclei (AGNs), the sites of mass accretion onto supermassive black holes, have been hosted by most galaxies at some point in their lifetime. X-rays are a direct and efficient means of identifying AGNs and measuring their intrinsic properties reliably. A recent breakthrough in this regard is the Nuclear Spectroscopic Telescope Array (NuSTAR), the first space satellite observatory with the ability to focus high-energy (i.e., ``hard''; >10 keV) X-ray photons. In this thesis I use NuSTAR to study the distant hard X-ray emitting AGN population, with a view to improving the cosmic census of AGNs as well as understanding their demography and evolution. In addition to these broad goals, a more specific focus is to identify elusive Compton-thick (CT) AGNs, which may represent an important phase of hidden black hole growth. Two overall approaches are taken: (1) optically selected Type 2 quasars suspected to be CT (i.e., candidate CTQSO2s) are deliberately targetted with NuSTAR; and (2) a large and unbiased serendipitous survey of ~500 X-ray sources is performed using almost all of the science data taken with the NuSTAR observatory over a 40-month period. For both of these complementary samples, the broad-band X-ray and multiwavelength properties are studied. For the candidate CTQSO2s, the addition of > 10 keV NuSTAR data provides an improvement compared to constraints with Chandra and XMM alone (i.e., with the most sensitive observatories at < 10 keV), generally allowing significantly higher column densities (Nh) and intrinsic AGN luminosities (Lx) to be constrained, and providing strong evidence for CT absorption in some cases. Implications for the Nh distribution of Type 2 quasars are discussed. For the NuSTAR serendipitous survey, an extensive ground-based followup program has been undertaken, which was crucial to obtain spectroscopic redshifts and classifications for the bulk of the sample. The serendipitous survey AGNs cover a redshift range of z=0.002 to 3.4 (median of < z > = 0.56) and a hard X-ray luminosity range of log(L_10-40keV [erg/s]) ~ 39 to 46. Singling out the most extreme likely-CT sources in the serendipitous survey gives an insight into the prevalence of such extreme systems within the general AGN population.

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Loubamono-Bessacque, Guy Claver. "Les populations du bassin de la Lesibi (Gabon) du début : du XVIIIème à la fin du XIXème siècle." Paris 1, 1992. http://www.theses.fr/1992PA010639.

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Le bassin de la Lesibi est situé au sud-est de l'actuelle république du Gabon. Différents groupes de populations se le partagent, notamment les Ikota, Ondasa, Ambama et Basamaye. Antérieurement à leur implantation dans le bassin de la Lesibi, ces populations vivaient dans le nord-ouest de l'actuelle république du Congo (Ambama) et au nord-est du Gabon d'aujourd'hui (Ikota, Ondasa et Basamaye). En l'état actuel des recherches, on ne peut déterminer la date d'implantation de ces populations dans la région. On sait seulement que, au XVIIIe siècle, elles étaient déjà en place. Ces populations entretenaient des relations de nature diverse entre elles et avec les habitants des régions voisines. Elles avaient aussi en commun nombre de traits de civilisation. Jusqu'à la fin du XIXe siècle, les étrangers, en l'occurrence les européens, n'avaient pas foulé le sol du bassin de la Lesibi, si l'on excepte le passage des italiens Attilio Pecile et Giacomo Savorgnan Di Brazza. En revanche, cette région, depuis le XVIIe siècle vraisemblablement, recevaient les produits manufactures. Ceux-ci étaient prises par les populations locales, qui vendaient même leurs semblables pour en acquérir The Lesibi bassin is situated to the south east of the present Gabon republica. Differents groups of populations that place, especially the Ikota, Ondasa, Ambama and Basamaye. Before their seattlement in the Lesibi bassin, those populations lived in the north west of the present Congo republica (Ambama) and to the north east of the Gabon of nowaday. It's not possible now in the present state of the research, to determine the seattlement date of those populations in that area. We just knew, in the XVIIIe century, the were established there. Those populations maintained different relations among themselves and with the others neighbor inhabitants. They share many common civilization characteristics. Untill the end of the XIXe century, the foreigners, the Europeans, hadn't trampled down the Lesibi Bassin if we except the Italian crossing Attilio Pecile and Giacomo Savorgnan Di Brazza. In return this territory since the XVIIe century probably, received manufactured products. Those ones were valued on the local populations, who even sold their yellow-men to have some

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Francis, Ocran Emmanuel. "The nature of the microjy source population." University of the Western Cape, 2015. http://hdl.handle.net/11394/5064.

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Masters of Science The study of the faint radio universe and of its properties has recently become a very active field of research not only because of the much improved capabilities of the SKA pathfinders but also because of the need to better plan for SKA surveys. These new facilities will map large areas of the sky to unprecedented depths and transform radio astronomy into the leading technique for investigating the complex processes which govern the formation and evolution of galaxies. This thesis combines multi-wavelength techniques, highly relevant to future deep radio surveys, to study the properties of faint radio sources. The nature of the faint radio sources is presented, over a large GMRT survey area of an area of 1.2 deg2 comprising 2800 sources. Utilising multi-wavelength data we have matched 85% of the radio population to Spitzer/IRAC and obtained a redshift estimate for 63%. The redshift associations are a combination of photometric and spectroscopic redshift estimates. This study investigates several multi-wavelength diagnostics used to identify AGN, using radio, infrared, optical and x-ray data . This analysis shows that various diagnostics (from the radio through the X-ray ones) select fairly different types of AGNs, with an evidence of a disagreement in the number of AGNs selected by each individual diagnostics. For the sources with redshift we use a classification scheme based on radio luminosity, x-ray emission, BOSS/SDSS spectroscopy, IRAC colors satisfying the Donley criterion, and MIPS 24ɥm radio-loud AGN criteria to separate them into AGNs and SFGs. On the basis of this classification, we find that at least 12.5% of the sources with redshifts are AGNs while the remaining 87.5% are adopted as SFGs. We explore the nature of the classified sources through the far-infrared radio correlation. We measure a median qIR value of 2:45± 0:01 for the SFGs and qIR value of 2:27 ± 0:05 for the AGNs. The decrease in the median value of qIR for the AGNs is a result of the additional AGN component to radio emission for the AGN-powered sources and find tentative evidence of an evolution of the qIR with redshift.

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Koot, Barbara. "Winter behaviour and population structure of fin whales (Balaenoptera physalus) in British Columbia inferred from passive acoustic data." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54230.

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Fin whales are acoustically active year-round, particularly during the winter breeding season when males produce song as a reproductive display. Little is known about movement patterns and population structure of the fin whale (Balaenoptera physalus) in the North Pacific. I used passive acoustic data recorded using bottom-mounted autonomous recording instruments to answer questions about the winter distribution, behaviour and population structure of fin whales in a high-latitude area of the eastern North Pacific Ocean. I found that fin whales are present in British Columbia (BC) waters throughout the winter, and their acoustic behaviour suggests that they are engaging in reproductive and possibly feeding behaviour. The presence of these individuals indicates that not all fin whales migrate south in the winter to low-latitude breeding grounds. I found that the majority of fin whales recorded in BC sang a doublet song with alternating ~13 s and ~17 s intervals between alternating classic and backbeat notes (song Type 2). At the most northerly recording site, and the two offshore sites, I found a few instances of a previously described doublet song type that has longer internote intervals (song Type 1). This suggests that two spatially segregated populations of fin whales are using BC waters, with the population producing song Type 2 being more coastal. Through a literature search, I found evidence of song Type 2 occurring from northern BC to Oregon. Song Type 1 has been documented off Southern California, the Bering Sea and the central North Pacific. My results are consistent with evidence showing that two genetically distinct fin whale populations occur in the eastern North Pacific, and that the population that produces song Type 2 is more closely related to the Southern Hemisphere subspecies of fin whale, than to the other population of fin whales in the North Pacific. My results show that BC waters are important for fin whales year-round, rather than just during the summer feeding season―and that the fin whales in BC likely belong to two distinct populations (one of which may belong to the Southern Hemisphere subspecies) and may require separate plans for their conservation and management. Science, Faculty of Zoology, Department of Graduate

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Combal, Cécile. "Mobilité, adaptation, reconversion : trajectoires croisées de territoires désindustrialisés, basse Romanche, moyenne Maurienne, haute Durance (Fin XIXe siècle - XXIe siècle)." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALH001.

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La désindustrialisation des territoires alpins de l’aluminium, sujet de la thèse, est envisagée sur la longue durée, à l’aune des transformations foncières et démographiques locales. Il s’agit de comprendre en quoi des mutations successives vécues par les territoires, l’industrialisation, la désindustrialisation, puis la reconversion touristique, sont des constructions ; comment elles sont mises en œuvre ; et quels sont leurs impacts au sein des communautés locales étudiées. Dans un premier temps, est privilégiée la présentation de clefs de lecture de l’industrialisation des territoires de moyenne Maurienne, de basse Romanche, et de haute Durance, de l’arrivée d’acteurs économiques extérieurs aux massifs, au développement d’une véritable politique sociale d’entreprise. Il s’agit ensuite de poser le cadre de la désindustrialisation et d’en affirmer le caractère construit. Pour ce faire, un jeu d’échelles est opéré entre, d’une part, les territoires mauriennais accueillant les usines de Saint-Jean, de la Saussaz et de La Praz, et d’autre part, les instances de décisions et de négociations nationales, politiques et économiques. Dès lors, il devient possible de développer deux cas d’études territorialisés, la fermeture de l’usine de l’Argentière en échange de contre-parties territoriales, et la fermeture de l’usine de Rioupéroux sans contre-parties de ce type. La désindustrialisation achevée, la mise en œuvre de reconversions touristiques s’amorce selon des temporalités, des modalités, et des ampleurs variées. La thèse conclut sur une mise en regard des trois mutations vécues par les communautés aluminières alpines au fil d’un XXe siècle étiré. Elle questionne le rapport à la modernité qu’entretiennent les territoires, une modernité ici entendue comme la métaphore d’une injonction sans cesse renouvelée. Chaque fois, il s’agit pour les communautés de fond de vallée de répondre à des modèles de développement qui s’avèrent rapidement obsolescents, imposés à la fois par le marché, par les milieux scientifiques et par la puissance publique This PhD dissertation seeks to understand the impact of de-industrialisation in alpine aluminium territories through changes in demographic and land-use on the long-term. More specifically we seek to understand how successive processes of industrialisation/de-industrialisation followed by tourism reconversion, were experienced ; constructed ; implemented ; and what their impacts on local communities were. First we review the key features of industrial development in the Moyenne Maurienne, the Basse romanche and the Haute Durance. We explore the arrival of external actors and the implementation of corporate social policies. Next we lay the framework to understand how the process of de-industrialisation is constructed. To that end we go back and forth between the Maurienne factories (Saint-Jean, la Saussaz, la Praz), the decision-making authorities and the relevant negotiating bodies. This allows us to focus on two case-studies : the closing of l’Argentière in exchange for social and economic benefits, and the closing of Rioupéroux without compensation. Finally, following the end of industrial activity, we seek to analyse the implementation of tourism reconversion policies. In each territory, they appear to be of varying intensity, to operate within different time frames and to differ in content. The dissertation concludes by comparing the lived experiences of the above communities in relation to these processes extending throughout the 20th century and beyond. It seeks to question the relation between these territoires and the trope of modernity. We find that in each case, the communities are compelled to abide by recurrent schemes of outdated development models imposed by the maket, scientific communities and public authorities

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34

Dudik, Rachel. "Low ionization nuclear emission line regions : the 'missing link' in the active galactic nucleus population." Fairfax, VA : George Mason University, 2007. http://hdl.handle.net/1920/2882.

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Thesis (Ph. D.)--George Mason University, 2007. Title from PDF t.p. (viewed Jan. 17, 2008). Thesis director: Shobita Satyapal. Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Physical Sciences. Vita: p. 217. Includes bibliographical references (p. 202-216). Also available in print.

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Schroeder, Matthew Jason. "Factors Related to the Timing of Anterior Cruciate Ligament Reconstruction Failure Among an Active Population." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1343664476.

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Nguyen, Hoang Minh Dung. "Information Extraction from Radiology Reports for a Population Based Cancer Registry." Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/9466.

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In a noisy corpus such as in clinical data, the text usually contains a large number of misspell words, abbreviations and acronyms that can be an obstacle to high quality information extraction and classification. Furthermore, the gold-standard training data needed for supervised learning usually contains many errors and inconsistencies due to differences in human annotators. In this research, a specialised proof-reading process for the clinical domain to resolve unknown tokens and convert scores and measures into a standard layout is introduced. The automatic coding of the texts increased the coded content significantly after the automatic correction process. Accuracy of the automatic coding and annotation of the notes which have not been coded by the clinical staff is suggested by the system output. To deal with the problem of noisy training data, this thesis proposes an algorithm for a method named “reverse active learning” which means applying active learning in reverse order to improve performance of supervised machine learning on clinical corpora. The effects of automatic proof-reading and reverse active learning are shown to produce results on the i2b2 2010 clinical corpus that are a state-of-the-art of supervised learning method and offer a means of improving all processing strategies in clinical language processing. Finally, a Cancer Staging Information Extraction System based on the combination of proposed methods of proof-reading, supervised learning, active learning and reverse active learning is presented. In this research, free-text reports are annotated for examples of the information to be extracted and then algorithms are developed that use the examples to compute a more general model of the desired content. Besides traditional supervised learning methods such as Conditional Random Fields and Support Vector Machines, active learning approaches are investigated to bring further improvement to information extraction system performance.

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Khaskhoussi, Tarek Langot François. "Réforme du système français de retraite et offre de travail en fin de cycle de vie." [S.l.] : [s.n.], 2008. http://cyberdoc.univ-lemans.fr/theses/2008/2008LEMA2002.pdf.

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38

Rengang, Yu. "L'évolution de la répartition sectorielle de la population active : l'expérience mondiale et les perspectives en Chine." Paris 1, 1990. http://www.theses.fr/1990PA010027.

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Selon la "loi de Petty-Clark", l'évolution des structures de la population active se caractérise par son passage du secteur primaire vers le secteur secondaire d'abord, et du secteur secondaire vers le secteur tertiaire ensuite. Dans les années 1960, Y. Sabolo a indiqué un nouveau phénomène, celui de l'hypertrophie du secteur tertiaire dans les pays en voie de développement. Dans la présente thèse, l'auteur indique un autre phénomène, le gonflement du secteur secondaire dans les pays socialistes et propose une nouvelle classification des structures de la population active en 5 types: la pyramide, la trompette, le tambourin, la bobine et la pyramide renversée. A partir de là, les deux modèles de l'évolution des structures sectorielle de la population active sont proposés: trompette--bobine--pyramide renversée et pyramide-tambourin-pyramide renversée. De plus, les tendances communes et les causes de l'évolution y sont considérées. Enfin, l'auteur a fait une prévision de l'évolution future en chine According to the Petty-Clark' law, the sectional evolution of the active population is first characterized by the passage from the primary sector to the secondary sector, and then from the secondary sector to the tertiary sector. In the 1960s, Y. Sabolo indicated a new phenomenon: hypertrophy of the tertiary sector in the developing countrys. In this thesis, the author point out a new phenomenon : the swell of the secondary sector in the socialist countrys and proposes a new classification of 5 types: the pyramid, the trumpet, the tambourin, the bobbin and the reversal pyramid. From this point, the author proposes two models of the structural evolution of the active population: trumpet--bobbin--reversal pyramid and pyramid-tambourin--reversal pyramid. In addition, the common tendencys and the causes of the evolution is also analysed. Lastly, the author suggests a prevision of the future evolution in china

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Smolčić, Vernesa. "The faint radio population in the VLA-COSMOS survey star forming galaxies and active galactic nuclei /." [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:16-opus-79548.

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Witte, Becky A. "Impacts of Climate Change and Population Growth on Water Stress in the Tucson Active Management Area." Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/293624.

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This study assesses the effects of a changing climate and population growth on water resources by modeling groundwater supplies in the Tucson Active Management Area. The finite-difference flow model, Modflow, is used to incorporate agricultural, municipal, and industrial well pumping along with natural and artificial recharge. This study expands on a Modflow model created by the Arizona Department of Water Resources to determine the impacts from limited water supplies and increased demand (Mason and Bota, 2006). Groundwater conditions and pumping in the Upper Santa Cruz and Avra Valley sub-basins are modeled starting in the year 1940 and continue to 2009. The model predicts pumping and recharge for the period of 2010 to 2050. During this projection period, nine scenarios based on various climate and population conditions are evaluated. Climate impacts are reflected in the amount of recharge entering the groundwater system. Local and regional climate conditions are incorporated since a large portion of the Tucson water supply is provided by the Colorado River water delivered along the Central Arizona Project (CAP). A decrease of 10% to the mean natural flow in the Colorado River over the next 50 years is used to predict Colorado River flows and shortages. Additionally, a 20% streamflow reduction case and two scenarios that evaluate the local and regional shortages individually are presented. Operational rules for the deliveries of the CAP water during shortage conditions are utilized to represent the system. The percentage of population growth is varied around the current case, which is extrapolated from data provided by the Arizona Department of Water Resources. Water demand is based upon the initial population, annual population growth, and gallons per capita day, which is a measurement of water use per person. The three population scenarios are limited growth, current case, and high growth. Results indicate groundwater depletion conditions are the worst during the high growth/shortage scenarios and best for the limited growth scenario. The change in storage of the aquifer is greatly driven by the pumping, which is dependent on population. For the shortage condition, the decline in natural recharge has a much larger effect on the change in water storage compared to the artificial recharge reductions due to shortages of CAP water.

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Foucault, Valérie. "Evaluation de l'aptitude physique d'une population active : le MST (mesure du seuil de tolérance à l'effort)." Caen, 1991. http://www.theses.fr/1991CAEN3056.

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42

Hilaire, Guy. "Peuplement et occupation des sols dans la région de Neufchâteau des origines à la fin du XIIIème siècle." Nancy 2, 2005. http://www.theses.fr/2005NAN21001.

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La région néocastrienne, zone frontière et stratégique, est formée des plateaux meusien et mosellan, du Saintois et de deux cuestas. Du Néolithique à la Tène, des clairières agricoles apparaissent dans les vallées et sur le plateau meusien. Au IIème siècle avant J. C. , les Leuques se replient sur les hauteurs. A l'époque romaine, de nombreuses villae naissent au pied des cuestas. Du VIIème au IXème siècle, la toponymie témoigne d'une importante vague de peuplement dans le Saintois et dans la plupart des vallées du plateau mosellan. Grâce aux actions conjuguées des seigneuries châtelaines et monastiques, une profonde mutation du paysage se produit durant la forte croissance des années 1150-1260 : recul de la forêt dans tous les finages, construction de moulins, érection de granges sur la partie supérieure des plateaux, extension des labours, des vignes et des pacages. La hausse de la production contribue à l'essor des villes de Châtenois et de Neufchâteau qui dominent successivement la région The Neufchâteau region, a strategic frontier zone, is made up of the Meuse and the Moselle plateaus, the Santois and two cuestas. From the Neolithic to the Tène period, agricultural clearings appeared in the valleys and on the Meuse plateau. In the second century B. C. , the Leuques withdrew to the heights. During the Roman period, many villae were founded at the foot of the cuestas. From the seventh to the ninth century, the toponymy reflects a major peopling in the Santois and in most of the valleys of the Moselle plateau. Thanks to the combined actions of the seigniorial and monastic domains, a significant transformation of the landscape took place during the strong growth between 1150 and 1260 : forest limits were pushed back on all community grounds, windmills were built, barns were erected on the upper part of the plateau, ploughlands, vineyards and pastures were expanded. The increase in production contributed to the rapid development of the cities of Châtenois and Neufchâteau, which alternately dominated the region

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Santos, Egídio Sousa. "La ville de Malanje dans l'histoire de l'Angola : de la fin du XIXe à 1975." Paris, EHESS, 2004. http://www.theses.fr/2004EHES0054.

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Cette thèse est consacrée à l’étude de la ville de Malanje dans l’histoire de l’Angola, de la fin du XIXe siècle à 1975. Il s’agit d’une ville d’Afrique située au centre-nord de l’Angola. L’Angola compte plusieurs régions et villes importantes, mais l’une de ces villes attire souvent l’attention, vu le niveau du développement d’activités économiques et commerciales du pays : c’est Malanje et sa région. Le choix de faire une étude sur l’histoire du mode d’organisation politique, commerciale et sociale de la ville de Malanje nous semble d’une importance capitale, contrairement à la plupart des cités angolaises connues aujourd’hui par leurs diverses activités Malanje représente une cité ou encore une agglomération dont la création est le fait des commerçants portugais, des métis luso-angolais, des Afro-brésiliens et enfin des Brésiliens. Le développement de Malanje s’inscrit dans la dynamique d’une part, des réseaux commerciaux anciens organisés par les marchands luso-africains, d’autre part, du développement de la colonisation agricole. Les alliances entre producteurs agricoles angolais locaux et commerçants ambulants de la région ont contribué à la mise en place des stratégies et des relations suffisamment puissantes afin contrôler les échanges. L’organisation de la ville de Malanje résulte non seulement des bouleversements enregistrés dans l’organisation politique, économique, commerciale et sociale précoloniale, mais aussi de la dépendance des conditions politiques spécifiques au Portugal. Au carrefour de grandes routes commerciales du nord du pays, Malanje a connu une évolution continue, résistant aux interventions européennes et portugaises, à l’époque où les autochtones de la région (les Ngola, les Njinga, les Imbangala et autres) cherchaient à se donner des moyens politiques, et surtout économiques, pour faire face aux nouvelles exigences du commerce international, après l’abolition de la traite négrière. Malanje a relevé ce défi avant tout grâce aux produits qui ont alimenté le commerce “ légitime ”, production de ses terres très fertiles, mais aussi de celles de toute la région. Nous savons en effet que les premières intentions portugaises n’étaient pas celles d’une conquête en vue d’une occupation territoriale ; il leur manquait des moyens et même de la volonté face à l’opposition des populations rencontrées dans la zone et à leur niveau d’organisation sociale. Comment en est-on arrivé à une situation où la ville de Malanje traduit le pouvoir portugais dans toute sa rigueur en même temps que dans sa politique de discrimination spatiale et de paupérisation des populations africaines dans cette ville ? Comment, peu à peu, se réduit le champ d’exercice du pouvoir africain à Malanje ? En cultivant les attitudes discriminatoires et racistes, les autorités portugaises ont soigneusement entretenu l’antagonisme entre la ville “ blanche ” et la ville “ noire ” à Malanje. Comment se manifeste cet antagonisme et, malgré quelques rares aménagements, quelles en sont les étapes jusqu’à l’indépendance de l’Angola en 1975 ?. Ces préoccupations principales sont traduites par deux hypothèses essentielles :- La première hypothèse cherche à examiner l’origine et le développement de la ville de Malanje au regard de la dynamique luso - africaine transformant cette ville, à la suite de l’abandon de la foire de Kasanje en 1861, en centre de contrôle d’activités économiques de la région. - La deuxième hypoyhèse considère Malanje comme la symbiose de deux villes, africaine et blanche, dont l’articulation dynamique et la croissance répondaient à la rationalité politique, économique et sociale portugaise This thesis is dedicated to the study of the city of Malanje in the history of Angola, the end of XIX-th century in 1975. It is about a city of Africa situated in the centre - North of Angola. Angola counts several regions and important cities, but one of these cities often draws attention, seen the level of the development of economic and commercial activities of the country : it is Malanje and the region. The choice to make a study on the history of the mode of political, commercial and social organisation of the city of Malanje seems to us of a major importance, contrary to most of the known Angolan cities today by their different activities Malanje represents a town or another a conglomeration of which creation is the fact of the Portuguese storekeepers, the luso-Angolan half-bloods, Afro-brésiliens and finally Brazilians. The development of Malanje joins in the dynamics on one hand, former (ancient) commercial networks organized by the luso-African traders, on the other hand, of the development of the agricultural colonization. Alliances among agricultural Angolan producer’s local and itinerant (mobile) storekeepers of the region contributed to the implementation of strategies and powerful enough relation’s afin to control exchanges. The organization of the city of Malanje results not only from turnovers registered (recorded) in the political, economic, commercial and social organization précoloniale, but also of the dependence of specific political conditions in Portugal. In the crossroads of commercial main roads of the North of the country, Malanje knew a continuous evolution, resisting to European and Portuguese interventions, when the autochthons of the region (Ngola, Njinga, Imbangala and the others) tried to give themselves political means, and especially economic, to face the new requirements of international trade, after the abolition of the draft négrier. Malanje took up this challenge above all due to the products which fed the "justifiable" business, production of his(its,her) very fertile lands, but also those of all the region. We know indeed that first Portuguese intentions were not those of the conquest with the aim of a territorial activity (occupation); they were short of means and even of the will in front of the opposition of the populations met in the zone and at their level of social organization. How did one arrive it at a situation where the city of Malanje translates Portuguese power in its entire rigor at the same time as in its politics (policy) of spatial discrimination and impoverishment of the African populations in this city? How, bit by bit, is reduced the field of African exercise of power to Malanje ? By cultivating the discriminatory attitudes and racists, Portuguese authorities carefully maintained antagonism between the "white" city and the "black" city to Malanje. How shows itself this antagonism and, in spite of some rare organizations, which are the stages of it until the independence of Angola in 1975 ?. These main preoccupations are translated by two essential hypotheses:-First hypothesis tries to examine origin and development of the city of Malanje towards the dynamics luso - African transforming this city, following the desolation of Kasanje's fair in 1861, in mission control of economic activities of the region. -The second hypoyhèse considers Malanje as the symbiosis of two cities, African and white, of which dynamic joint (articulation) and growth answered the Portuguese political, economic and social rationality

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Mytton, Oliver. "A population perspective on physical activity and health." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/264414.

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Regular physical activity reduces the risk of many chronic diseases. Consequently, the promotion of it and particular types (e.g. walking and cycling for travel), have become a priority for governments seeking to improve health and constrain rising demand on health services. Despite this many uncertainties persist. The aim of this thesis is to address two particular areas of uncertainty: a) the association of walking and cycling for travel with indices of health and well-being; b) and the extent to which increases in physical activity will reduce need for health and social care. The first part of my thesis consists of three studies that describe the health benefits associated with walking and cycling to work among working age adults. The first is a longitudinal study of the associations between maintenance of active commuting with sickness absence and well-being using the Commuting and Health in Cambridge dataset. The second, using the same dataset, describes the longitudinal associations between maintenance of active commuting and self-reported body mass index. Building on this, the third study using a large cohort study (the Fenland Study) with detailed characterisation of diet and physical activity (including objective measurement) describes the baseline associations between active commuting and objective measures of adiposity. The second part of my thesis describes the development of a combined microsimulation multi-state life table model that is used to characterise the effects of a population ‘shift’ in physical activity on the burden of six major diseases at the population-level. Specifically, it seeks to better describe the effect of increases in physical activity on healthcare need considering not just the effect of physical activity on disease incidence but also the effect on healthcare need arising from consequent survival to an older age (at which disease incidence is higher), and contrasts this with a method that does not make allowance for increased survival. The findings of this thesis provide evidence of the importance of walking or cycling to work in maintaining or improving the health and well-being of working age adults. It suggests that increases in physical activity, even after allowance for increased survival, are likely to reduce need for healthcare, although the reductions in need are less than might be assumed when allowance is not made for increased survival. Taken together this work provides a stronger empirical basis to inform public health practice. A stronger ‘health case’ for active travel can be made. The benefits of which should be communicated to individuals choosing how to travel as well as policy makers and others who can influence the determinants of active travel. It also provides a more realistic and nuanced understanding of how increases in physical activity may affect future healthcare need.

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45

Khaskhoussi, Tarek. "Réforme du système français de retraite et offre de travail en fin de cycle de vie." Le Mans, 2008. http://cyberdoc.univ-lemans.fr/theses/2008/2008LEMA2002.pdf.

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Le vieillissement de la population est l’un des grands enjeux auxquels sont confrontés les pays européens, et en particulier la France. Au cours des prochaines années, la France connaîtra une forte augmentation de la part des personnes âgées dans la population et une diminution marquée de la population des classes d’âge en âge de travailler. Sans réforme des retraites et plus généralement du marché du travail des seniors, la proportion des inactifs âgés par travailleur doublera d’ici à 2050. Conjuguée à l’augmentation de la longévité (les hommes qui ont pris leur retraite en 2004 ont une espérance de vie de 21 ans, alors qu’elle n'était que de 10. 8 ans en 1970), un vieillissement de cette ampleur exercerait de vives pressons sur les budgets publics : les dépenses de retraites passeront de11. 6 % du PIB en 2000 à 13. 8 % en 2020. Etant donné la multiplicité des facteurs qui empêchent les seniors de continuer de travailler, la seule réforme des retraites ne suffira pas pour développer les possibilités d’emploi pour les travailleurs en fin de carrières. Néanmoins, les mécanismes financiers inscrits dans le systèmes de retraite et autres dispositifs sociaux jouent un grand rôle dans l’arbitrage entre travail et retraite, et il est important que les seniors n’aient pas à supporter un lourd prélèvement fiscal s’ils choisissent de continuer de travailler. C’est ainsi que les incitations financières en faveur de la poursuite de l’activité doivent être renforcées. Si l’on parvenait à encourager les plus âgés à rester plus longtemps en activité, cela pourrait être bénéfique sur au moins deux plans : cela améliorait la situation des finances publiques et cela stimulerait la croissance de la population active. Les travaux empiriques de Hairault, Langot et Sopraseuth [2007] montrent que l'âge anticipé de retraite explique significativement la diminution des taux d'emploi en fin de cycle de vie. En effet, l'anticipation d'une retraite très proche peut rendre tout investissement sur le marché du travail non rentable. Comme le montrent, Hairault, Langot et Sopraseuth [2006], la théorie de la recherche d'emploi permet d'expliquer pourquoi un horizon court diminue l'intensité de la recherche d'emploi et donc le taux d'emploi à l'approche de l'âge de la retraite, en expliquant les faibles taux d'activité aux âges élevés par la faiblesse des incitations financières à rester en activité au delà d'un certain âge, qu'elles soient dues au système de retraite proprement dit ou à différents dispositifs de retraite anticipée. Toutefois, l'investissement sur le marché du travail ne se limite pas aux efforts de recherche d'emploi des chômeurs. Ainsi, la distance relativement à l'âge du taux plein, qui détermine de façon certaine un horizon court, est un facteur explicatif du faible investissement des offreurs de travail, qu'ils soient chômeurs (effort de recherche d'emploi) ou qu'ils soient employés (effort de formation). Au delà des faibles incitations à la reprise d'emploi, expliquant le faible taux d'emploi des seniors, un horizon court peut donc également rendre compte du plus faible niveau de productivité. Cette dernière se serait réduite, ou plus exactement ne serait plus suffisante pour compenser leurs salaires, rigides à la baisse. Dans cette thèse, nous proposons d’exposer dans un premier chapitre, les faits empiriques et les principales contributions théoriques expliquant la décision de départ à la retraite. Dans un second chapitre, nous proposons d’évaluer l’incidence des institutions françaises (pré-retraite et retraite) sur le taux d’emploi des seniors. Le chapitre 3 fournit une évaluation comparée des différentes politiques incitatives de prolongement d’activité. Pour tenir compte de l’impact sur le productivité, le chapitre 4 généralise l’approche des chapitres précédents en intégrant la formation de capital humain. Enfin, dans un dernier chapitre, nous proposons critique des politiques ayant pour objectif d’inciter à offrir plus longtemps son travail en tenant compte d’une rigidité salariale.

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46

Draper, Aden R. "Understanding the connection between active galactic nuclei and host star formation through multi-wavelength population synthesis modeling." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45748.

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Supermassive black holes, black holes with masses <106 Msun, are found at the centers of all massive galaxies. These massive black holes grew from smaller seed black holes through accretion events. Accreting black holes are very bright in the radio through very hard X-ray spectral regimes. Due to the location of these accreting black holes at the centers of galaxies, they are referred to as active galactic nuclei (AGN). It is understood that AGN are an important phase of galaxy evolution; however, the role of AGN in massive galaxy formation is very poorly constrained. Here, the unique tool of multi-wavelength population synthesis modeling is used to study the average properties of AGN and their host galaxies with a focus on host galaxy star formation and the role of black hole growth in galaxy evolution. Knowledge of the AGN population from deep X-ray surveys is combined with theoretical AGN spectral energy distributions to predict various observables of the AGN population in wavelength regions from the far infrared to very hard X-rays. Comparison of the model predictions to observations constrains the model input parameters and allows for the determination of average properties of the AGN population. Particular attention is paid to a special class of AGN known as Compton thick AGN. These AGN are deeply embedded in gas and dust such that the column density obscuring the line of sight to the central engine of the AGN exceeds 1/σT ~ 10²⁴ cm⁻², where σT is the Thomson cross-section of the electron---a column density comparable to that of the human chest. Theoretical and simulational evidence suggest that these Compton thick AGN may be recently triggered, rapidly accreting AGN, making them of special interest to researchers. I found that Compton thick AGN are likely to contribute ~20% of the peak of the cosmic X-ray background (XRB) at ~30 keV and demonstrated that a significant portion of Compton thick AGN may be accreting very rapidly. Moreover, Compton thick AGN do not appear to follow the orientation based unified model of AGN. According to the unified model, AGN exhibit a range of obscuration levels due to a dusty 'torus' which, depending on the orientation of the torus to the observer's line of sight, may obscure the central engine of the AGN. Upon further investigation into the stellar populations of AGN host galaxies, it appears that the unified model holds in general at z < 1, but not at z > 1. I found that this is likely due to the dominant triggering mechanism of AGN switching from major mergers at z > 1.5 to secular processes by z ~ 1.

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Archambault, Richard. "Le marché du travail canadien : une analyse des chocs cycliques, de redistribution et sur la population active." Mémoire, Université de Sherbrooke, 1995. http://hdl.handle.net/11143/8255.

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Ce mémoire représente un travail d'économétrie appliquée dans le cadre de l'économie du travail au Canada. À partir d'une approche de flux entre les emplois occupés, le chômage et les nonactifs, nous caractérisons trois types de chocs présents sur le marché du travail canadien soit, les chocs cycliques, de redistribution et sur la population active. Par la suite, nous estimons ces chocs en appliquant la procédure de Johansen et Juselius (1990), un modèle VAR avec vecteurs de cointégration. Ainsi, nous pouvons décomposer le taux de chômage agrégé en trois séries qui correspondent à chaque type de choc. Cette décomposition permet de dégager les conclusions suivantes. Le chômage cyclique démontre peu d'effet de persistance et a dominé la récession de 1981-82. La persistance du taux de chômage au Canada depuis le début des années 1980 est attribuable en majeure partie au chômage de redistribution. Finalement, le chômage provenant des chocs sur la population active est affecté d'une tendance positive.

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Volonteri, Marta, Amy E. Reines, Hakim Atek, Daniel P. Stark, and Maxime Trebitsch. "High-redshift Galaxies and Black Holes Detectable with the JWST: A Population Synthesis Model from Infrared to X-Rays." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/626181.

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The first billion years of the Universe has been a pivotal time: stars, black holes (BHs), and galaxies formed and assembled, sowing the seeds of galaxies as we know them today. Detecting, identifying, and understanding the first galaxies and BHs is one of the current observational and theoretical challenges in galaxy formation. In this paper we present a population synthesis model aimed at galaxies, BHs, and active galactic nuclei (AGNs) at high redshift. The model builds a population based on empirical relations. The spectral energy distribution of galaxies is determined by age and metallicity, and that of AGNs by BH mass and accretion rate. We validate the model against observations, and predict properties of galaxies and AGN in other wavelength and/or luminosity ranges, estimating the contamination of stellar populations (normal stars and high-mass X-ray binaries) for AGN searches from the infrared to X-rays, and vice versa for galaxy searches. For high-redshift galaxies with stellar ages <1 Gyr, we find that disentangling stellar and AGN emission is challenging at restframe UV/optical wavelengths, while high-mass X-ray binaries become more important sources of confusion in X-rays. We propose a color-color selection in the James Webb Space Telescope bands to separate AGN versus star-dominated galaxies in photometric observations. We also estimate the AGN contribution, with respect to massive, hot, and metal-poor stars, at driving high-ionization lines, such as C IV and He II. Finally, we test the influence of the minimum BH mass and occupation fraction of BHs in low-mass galaxies on the restframe UV/near-IR and X-ray AGN luminosity function.

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Hviding, Raphael E., Ryan C. Hickox, Kevin N. Hainline, et al. "Characterizing the WISE-selected heavily obscured quasar population with optical spectroscopy from the Southern African Large Telescope." OXFORD UNIV PRESS, 2018. http://hdl.handle.net/10150/627140.

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We present the results of an optical spectroscopic survey of 46 heavily obscured quasar candidates. Objects are selected using their mid-infrared (mid-IR) colours and magnitudes from the Wide-Field Infrared Survey Explorer (WISE) anzd their optical magnitudes from the Sloan Digital Sky Survey. Candidate Active Galactic Nuclei (AGNs) are selected to have mid-IR colours indicative of quasar activity and lie in a region of mid-IR colour space outside previously published X-ray based selection regions. We obtain optical spectra for our sample using the Robert Stobie Spectrograph on the Southern African Large Telescope. 30 objects (65 per cent) have identifiable emission lines, allowing for the determination of spectroscopic redshifts. Other than one object at z similar to 2.6, candidates have moderate redshifts ranging from z = 0.1 to 0.8 with a median of 0.3. 21 (70 per cent) of our objects with identified redshift (46 per cent of the whole sample) are identified as AGNs through common optical diagnostics. We model the spectral energy distributions of our sample and found that all require a strong AGN component, with an average intrinsic AGN fraction at 8 mu m of 0.91. Additionally, the fits require large extinction coefficients with an average E(B - V)(AGN) = 17.8 (average A(V)(AGN) = 53.4). By focusing on the area outside traditional mid-IR photometric cuts, we are able to capture and characterize a population of deeply buried quasars that were previously unattainable through X-ray surveys alone.

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Kou, Tzuyung Doug. "Watchful Waiting Active Surveillance in Prostate Cancer Patients a Population-Based Study Using the SEER-Medicare Linked Database." Cleveland, Ohio : Case Western Reserve University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1207309899.

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Thesis (Ph.D.)--Case Western Reserve University, 2008 Title from PDF (viewed on 26 May 2009) Includes abstract Department of Epidemiology and Biostatistics Includes bibliographical references [and appendices] Available online via the OhioLINK ETD Center

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Dissertations / Theses on the topic 'Population active à la fin'

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