O mercúrio (Hg) é um metal tóxico extensamente estudado em todo mundo, distribuído no ambiente a partir de fontes naturais ou antropogênicas e que oferece risco a população por ser altamente biocumulativo e possuir efeitos nocivos à saúde. Até algum tempo atrás, acreditava-se que a principal fonte de exposição ao Hg na Região Amazônica, decorria do uso deste metal para amalgamação de ouro nos garimpos da região. No entanto, o Hg é encontrado naturalmente nos solos da Região Amazônica e ao atingir os sistemas aquáticos, favorecidos principalmente pela erosão e pelas chuvas, passa por um processo de metilação catalisada por microorganismos, dando origem à forma orgânica do metal, o metilmercúrio (MeHg). Esta forma do metal se acumula no sedimento dos rios e em peixes representando atualmente a principal fonte de exposição ao mercúrio em população ribeirinha. Os biomarcadores de exposição ao Hg são freqüentemente utilizados para identificar e estimar o risco em que um indivíduo ou uma população está exposta. No entanto, pouco se conhece a respeito das variações inter-individuais de cada um deles. Neste sentido, este estudo teve como objetivo avaliar as variações inter-individuais em biomarcadores de exposição ao Hg em uma população ribeirinha do rio Tapajós, Pará. Para tal, 410 ribeirinhos, residentes em 12 comunidades ao longo do rio Tapajós, no estado do Pará participaram do estudo. Foram determinadas as concentrações de mercúrio total (THg) em sangue total, plasma, eritrócito, urina e de IHg e MeHg em cabelo dos voluntários. As concentrações de THg no sangue total variaram de 1,7 a 288,9 µg/L e no plasma de 0,2 a 40,0 µg/L. A concentração de THg no plasma apresentou uma alta correlação com as concentrações de THg em sangue total (r=0,7529, p<0,0001). A fração plasmática de THg variou 0,5% a 61% e não apresentou qualquer correlação com as concentrações de THg em sangue total (r= 0,06284, p=0,2041), indicando que a mobilização de THg para o plasma não ocorre devido à saturação dos eritrócitos. A distribuição de THg entre eritrócitos e plasma observada nesta população, é diferente do que foi observado em outros estudos sobre exposição à MeHg. As concentrações de THg no cabelo variaram de 0,97 a 62,4 µg/g e apresentaram uma correlação muito forte com as concentraçoes no sangue (r=0,8718, p<0,0001) indicando que as concentrações de THg no cabelo refletem as concentrações de THg no sangue. Também foi observada uma forte correlação entre as concentrações de MeHg e de IHg no cabelo (r=0,8979, p<0,0001), confirmando as informações da literatura, que sugerem que a fração de IHg no cabelo se deve a demetilação no sangue, no folículo capilar ou no preparo da amostra e análise. Em relação a razão entre concentração de mercúrio entre cabelo e sangue, observamos uma elevada variação entre os indivíduos, de 1:13 a 1:13274. Entre as mulheres observamos que esta variação ocorre de acordo com a idade. Resultados preliminares apontam para uma considerável variação inter-individual nos biomarcadores de exposição na população em estudo, indicando a necessidade de se identificar os fatores que influenciam este achado. Considerando a cinética do mercúrio, podemos concluir que estas variações inter-individuais na fração plasmática, podem alterar a taxa de eliminação do Hg e também os efeitos tóxicos decorrentes da exposição. Palavras- Chave: biomarcadores de exposição, mercúrio, variações inter-individuais / Mercury (Hg) is a toxic metal widely studied worldwide. In the atmosphere Hg may occur due to natural or anthropogenic sources. It offers risk to the population due to be highly bioaccumulated and to cause harmful effects to humans. Gold Mining activities were considered in the past the main sources of Hg contamination in the Amazon region. However, new findings indicated that Hg is naturally found in the soils of the Amazon area. When reaching the aquatic systems, facilitated mainly by the erosion and for the rains, the inorganic mercury is methylated, by microorganisms, forming the more toxic form methylmercury (MeHg). This form of the metal accumulates in the sediment of the rivers and in fish, meaning the main exposure source of mercury to riverine population. Biomarkers of exposure to Hg (levels of Hg in blood, plasma, urine, hair) are frequently used to identify and to esteem the risk of an individual or a population to harmful effects. However, little it is known regarding the inter-individual variations of these biomarkers. In this sense, this study evaluated inter-individual variations in the biomarkers of exposure to mercury (Hg in plasma, blood, urine and hair) in a riverside population (Tapajós river, Pará). Volunteers (n=410), residents in 12 communities along the Tapajós river, in the state of Pará participated in the study. Total mercury (THg) levels were determinated in whole blood, plasma, red blood cells and urine and of IHg and MeHg in hair. The concentration of mercury ranged from 1.7 to 288.9 µg/L and of plasma from 0.2 to 40.0 µg/L. The concentration of THg in the plasma presented a high correlation with concentrations of Hg in total blood (r=0.7529, p<0.0001). The plasmatic fraction of THg ranged from 0.5% to 61% and did not present any correlation with the concentrations of THg in the whole blood (r= 0.06284 p=0.2041), indicating that the mobilization of Hg to the plasma does not occur to the saturation of the red blood cells. The distribution of THg between red blood cells and plasma observed in this population is in disagreement when compared to other populations. The mercury concentrations in hair ranged from 0.97 to 62.4 µg/g and presented a very strong correlation with the whole blood (r=0.8718, p<0.0001), indicating that the concentrations of Hg in hair reflect the concentrations of THg in blood. Also a strong correlation was observed among the concentrations of MeHg and of IHg in hair (r=0.8979, p<0.0001), confirming the information in the literature, that suggest the fraction of IHg in hair is due to demethylation process or by sample preparation and analysis. Regarding the ratio between concentration of mercury between hair and blood, we observed a high variation between individuals, ranged from 1:13 to 1:13274. Among the women we observed this variation occurring according to age. In conclusion our results together demonstrated a considerable inter-individual variation in the biomarkers of exposure to mercury in the study population, demonstrating probably a different rate of biotransformation and elimination of Hg in this population. Then, future studies are necessary to elucidate factors are influencing this variation.

This dissertation encompasses three articles concerning Sawyer's (2007) theory of group flow in the context of higher education, including a literature review, and two interpretive studies. In the literature review and in the first interpretive research article, the results of the research illuminated the applicability of themes of group flow in collaborative settings in higher education in themes of vision, ownership and contribution, and communication. The final article provides a description of the roles of student lead and professor in this environment and the unique ways that they may have encouraged those themes in the studio. The context for this study was the BYU Animation Studio, using video footage of students working in the computer lab, in their Daily meetings, and video interviews with students and professors in the program. The footage focused on one year of the senior project, with a core group of students coordinating efforts to create an animated short. Students involved in the senior film were mostly juniors and seniors coming from different academic departments, including Fine Arts, Engineering, and Computer Science. In the descriptive article, we gained further insights into the experience of group flow in a higher education setting. Several of the themes from the data resonated with the literature on group flow. Students working on the project had both project and people-oriented goals. They took initiative to solve problems and work through personal conflicts with group decisions, and made efforts to share their knowledge with other students. As group members communicated, they often validated and built off of others' ideas, putting the interests of the group above personal interests. In the same context, using the same methods, we were able to observe ways that student leads and teachers tried to enhance the group experience. Student leads and teachers made different contributions in that respect. Student leads contributed the actual project vision, breaking up the project into tasks for which students could volunteer and take initiative. Student leads also promoted friendship and communication within the group. Professors taught collaboration skills, and supported student initiatives. Professors also provided opportunities for students to collaborate across departments, while practicing collaboration between faculty members.

La problématique principale de cette thèse de doctorat est de comprendre les processus au travers desquels la protection de l’enfance est devenue un problème social en Amérique, ˆ partir d’une description et d’une analyse du parcours de l’Institut Interaméricain de l’Enfant et de l’Adolescent entre 1916 et 1989. Pour cela, nous abordons un corpus documentaire spécifique les Actes et les Bulletins de l’Institut dans une perspective généalogique, en mettant l’accent spécifiquement sur la réalité historique de leurs contextes sociaux de production. Le choix de l’Institut comme cas d’étude permet ainsi de développer les multiples questionnements qui sont ˆ la base de cette recherche: Comment ont été produits les discours qui se réclamaient (au moins de manière temporelle) véridiques par rapport ˆ l’enfance dans les Amériques? De quelle manière ces discours ont-ils participé ˆ la construction d’un domaine de connaissance et d’action spécifique appelé protection de l’enfance? Comment ce domaine a-t-il pris corps dans un organisme international spécifique? Quels processus et mécanismes ont soutenu le processus d’institutionnalisation transnationalisé ? Quels furent les acteurs prépondérants dans ce processus? Quel type de rapports ont-ils établi entre eux? Quels sont les éléments persistants et les éléments de discontinuité historique que l’on peut identifier dans les représentations et les pratiques qu’ils ont arborés? Quels ont été leurs buts et leurs motivations?Autour de ces questionnements, nous cherchons ˆ articuler une problématisation historique du présent. Cet exercice méthodologique se soutient dans un intérêt de repenser les conditions d’émergence du régime de droits de l’enfance, inauguré avec la Convention Internationale des Droits de l’Enfant, en 1989. / The main goal of this doctoral thesis is to understand the processes that have led to child protection becoming a social problem in the Americas. We approach this subject through the description and the analysis of the history of the Inter-American Children's Institute between 1916 and 1989. This study is based on a specific corpus of documents the Institute’s proceedings and newsletters, considered from a genealogical perspective with a special emphasis on the historic reality of the social contexts of production of these documents. The Institute, as a case study, allows us to pose numerous questions, which serve as a basis for this research: how have discourses that have reclaimed (at least temporarily) a value of truth regarding infancy been produced in the Americas? How have these discourses collaborated in the construction of a specific domain of knowledge and action called “child protection”? In which ways has this domain appeared in a specific International organism? What processes and mechanisms support the process of institutionalization at a transnational level? Who were the main actors in this process? What kind of relationships did they establish among themselves? What parts of the representations and the practices that they conducted persisted and what parts were discontinued? What were their goals and motivations? We seek to articulate a historical problematization of the present around these issues. This methodological exercise stems from the interest in a reconsideration of the conditions of emergence of the regime of children’s rights, inaugurated with the ratification of the International Convention on the Rights of the Child, in 1989. / El problema principal de esta tesis doctoral es comprender los procesos a través de los cuales la protección de la infancia deviene un problema social en América. Esto se lleva a cabo a partir de la descripción y el análisis de la trayectoria del Instituto Interamericano del Niño, la Niña y Adolescentes, entre 1916 y 1989. Para ello, abordamos un corpus documental específico –las Actas y los Boletines del Instituto– desde una perspectiva genealógica, poniendo especial atención en la realidad histórica de sus contextos sociales de producción. El Instituto como caso de estudio, nos permite desarrollar las múltiples interrogantes que están en la base de esta investigación: ¿Cómo se han producido los discursos que han reclamado (al menos temporalmente) un valor de verdad respecto de la infancia en las Américas? ¿Cómo esos discursos colaboraron en la construcción de un dominio de conocimiento y acción específico llamado “protección de la infancia”? ¿Cómo ese dominio toma cuerpo en un organismo internacional específico? ¿Qué procesos y mecanismos sostienen el proceso de institucionalización transnacionalizado? ¿Quiénes fueron los actores preponderantes en ese proceso? ¿Qué tipo de relaciones entablaron entre ellos? ¿Cuáles son las persistencias y discontinuidades históricas de las representaciones y prácticas que ellos enarbolaron? ¿Cuáles fueron sus objetivos y motivaciones? En torno a estas interrogantes buscamos articular una problematización histórica del presente. Este ejercicio metodológico se sostiene en un interés por repensar las condiciones de emergencia del régimen de derechos de infancia, inaugurado con la ratificación de la Convención Internacional de los Derechos del Niño, en 1989. Palabras clave: protección de la infancia, organismo internacional, América Latina, interamericanismo, historia del presente

This dissertation analyzes how three female artists of Greater Mexico (the Mexican cabaret artist Astrid Hadad, the Mexican-American singer Lila Downs and the Chicana digital artist Alma López) construct and represent national, ethnic, and gender identity in their performances within a border and/or transnational context. I explore how their choice of art form facilitates the construction of their own identities. My theoretical methodology embraces a cultural-studies approach to dramatic, visual and performative texts. All of these play an important role in redefining female Chicana/Mexican- American/Mexicana identity as a site of cultural and political contestation and struggle. The interdisciplinary character of this project corresponds to the nature of performance itself and to the search for female identity formation within Greater Mexico. I use the term Performing Nation to focus on how these artists embody and enact specific regional and national identities through, among others, costume choice, vocal inflection, song choice and imagery. The Mexican cabaret singer Astrid Hadad ironically performs Mexico through cabaret. Her humorous critiques of Mexican gender norms encourage her audience to envision a more egalitarian future for Mexico. The Mexican- American pop singer Lila Downs performs Greater Mexico through folk culture. I discuss how her oscillation between the new and the "authentic" promotes the idea that folklore is malleable and willing to change. The Chicana visual media artist Alma López performs a queer Greater Mexico in cyberspace through digital art. I show how her play on female dualisms found in Mexican and Chicano culture helps open a space for the contemporary Lesbian Chicana. In their work these artists play with iconography from the Post-Mexican Revolution period. Astrid Hadad highlights female figures such as La Soldadera, La Muerte, Coatlicue, La Virgen de Guadalupe and Frida Kahlo that are important to Mexican culture. Downs incorporates imagery through myth and storytelling, both central to her performances. Alma López plays on indigenous and Chicano art in her digital prints. Through the absorption of symbolic, religious and popular iconography these artists construct mobile identities that extend the Mexican cultural sphere across the northern border into the U.S. The porous nature of the border enables these northern identities to circulate back to Mexico. By participating in this cross-border identity building process, Hadad, Downs and López situate themselves as public figures, as women artists, within the Greater Mexico that they are reshaping.

One of the most rapidly expanding areas of research in psychology has been poison-based aversion learning (PBAL). The PBAL paradigm typically involves: exposing an animal to a novel substance; inducing illness following ingestion of that substance; and then providing access to the substance at a later time. The initial reaction to the novel substance is generally to reduce consumption, a finding labeled neophobia. The reduction of substance intake on test day is called learned aversion. Following demonstrations of cue-to-consequence specificity (i.e., the differential associability of some stimuli with certain consequences) in PBAL research with rats, recent research has focused on PBAL by avians. Such research has been instigated by speculation that avians might be specially adapted to better associate visual rather than flavor stimuli with illness. Studies to determine the relative salience of visual or flavor cues in avian PBAL have reported contradictory findings. A number of methodological differences exist between these studies including differences in stimulus intensity and type, duration between conditioning and assessment, and method of assessment. The current series of experiments made several methodological improvements to clarify the issue of cue to consequence specificity in PBAL with avians. Three experiments with pigeons as subjects are reported. The first experiment equated (scaled) stimulus intensity across different sense modalities by equating neophobic responses to various concentrations of salt, sour, and red water. The second experiment determined the extended effects of the illness-inducing stimulus alone on fluid consumption by pigeons in a restricted access to water environment. The third experiment was based upon results from the first two experiments and assessed aversion, at two different post-injection times, to one of two concentrations of either salt, sour, or red water CSs. In addition, a compound (flavor plus color) conditioning group was employed. Aversion was a function of flavor or color stimulus intensity. No differences were observed in degree of aversion demonstrated by groups receiving stimuli equated for initial suppression. Evidence for overshadowing or potentiation was not found. The results support the position that neither flavor or color stimuli are necessarily the most salient in avian PBAL.

The main aim of the project is to launch multiple processes and have those processes communicate with each other using peer to peer communication to eliminate the problems of multiple processes running on a single server, and multiple processes running on inhomogeneous servers as well as the problems of scalability. This entire process is done using MPICH which is a high performance and portable implementation of Message Passing Interface standard. The project involves setting up the passwordless authentication between two local servers with the help of SSH connection. By establishing a peer to peer communication and by using a unique shell script which is written using MPICH and its derivatives, I am going to demonstrate the process of inter-process communication between the servers.

Actuellement les communications véhiculaires sont devenues une réalité guidée par diverses applications. Notamment, la diffusion de vidéo de qualité élevée avec des contraintes de faible latence requises par les applications temps réel. Grâce au niveau de compression jamais atteint auparavant, l’encodeur H.265/HEVC est très prometteur pour la diffusion de vidéos en temps réel dans les réseaux ad hoc véhiculaire (VANET). Néanmoins, la qualité de la vidéo reçue est pénalisée par les mauvaises caractéristiques du canal de transmission (disponibilité, non stationnarité, rapport signal à bruit, etc.). Afin d’améliorer et d’assurer une qualité vidéo minimale à la réception nous proposons dans ce travail une optimisation conjointe source-canal-protocole de la transmission en tenant compte à la fois des paramètres de transmission et d’encodage vidéo. Dans un premier temps, nous montrons l’intérêt et le gain apporté par les solutions dites inter-couches « cross-layer ». Par la suite, nous développons deux approches l’une exploitant un « cross-layer » entre la couche application et la couche MAC et une seconde exploitant les protocoles de transports dans l’adaptation du flux vidéo. En ce qui concerne la première approche nous proposons une solution utilisant une gestion hiérarchique des trames au niveau des files d’attentes de la couche MAC, basée sur l’importance des images du flux vidéo. Dans une seconde solution, nous retenons le codage par descriptions multiples comme solution de protection à la source. Les résultats de simulations obtenus pour plusieurs types de scénarios véhiculaires réalistes montrent que les différents schémas de transmission véhiculaire proposés offrent des améliorations significatives en termes de qualité vidéo à la réception et de retard de bout en bout par rapport aux schémas classiques. / At present, vehicular communications have become a reality guided by various applications. In particular, high-quality video delivery with low latency constraints is required for real-time applications. The new state-of-the-art high-effciency video coding (HEVC) standard is very promising for real-time video streaming in vehicular ad hoc networks (VANET). Nevertheless, these networks have variable channel quality and a limited bandwidth that penalizes the overall performances of end-to-end video transmission. In order to meet these constraints, we proposed in this work to consider both transmission and video encoding parameters through a joint source-channel-protocol coding approach to provide an improvement in video transmission. First, we have shown the interest and the gain brought by the "cross-layer" solutions. Then, we developed two approaches. The first one exploits a "crosslayer" solution between the application layer and the Medium Access Control (MAC) layer while the second exploits the transport layer protocols in the adaptation of the video stream. Regarding the first approach, we have proposed solutions to allocate the frames to the most appropriate Access Category (AC) queue on the MAC layer based on the image importance in the video stream. In another solution, we chose multiple descriptions source coding as an error resilient solution. Thus, the simluation results obtained for different realistic vehicular scenarios demonstrate that the proposed transmission schemes offer significant video quality improvements and end-to-end delay reduction compared to conventional transmission schemes.

En 1992, à l'occasion de la réforme du code pénal, décision fut prise d'unifier les différentes sanctions pénales sous la seule bannière de la « peine » ; ce faisant, l'existence formelle des mesures de sûreté semblait promise à une complète désuétude. Pourtant, à partir de 2004, par une volte-face remarquée, le législateur institua des mesures de sûreté expressément dénommées comme telles,rompant ainsi l'unité lexicale qu'il avait lui-même établie une décennie auparavant. Il en profitait, desurcroît, pour consacrer la notion contestée de dangerosité comme fondement desdites mesures.La doctrine y vit un « renouveau des mesures de sûretés ». Une telle réapparition formelle a certes des causes conjoncturelles évidentes, tenant à l'opportunité politique de déroger au régime des peines, notamment en matière d'application de la loi dans le temps, mais elle ne saurait s'y réduire ;en effet, elle s'explique encore par des raisons structurelles qui tiennent à la nature de la mesure de sûreté, devant s'analyser comme une fonction – la garantie de la bonne exécution par un individu dangereux de l'obligation de resocialisation mise à sa charge – susceptible d'être exprimée par divers mécanismes : peines complémentaires, mesures de la phase d'instruction, modalités d'application des peines…L'analyse démontre que la mesure de sûreté n'avait pas déserté le droit criminel et qu'en fait de« renouveau », il s'est principalement agi, pour le législateur français, d'en étendre l'empire en multipliant les supports de cette fonction de garantie. / In 1992, in the context of the reform of the Criminal Code, decision was made to unify all criminal sanctions under the sole notion of “penalty” ; therefore, the formal existence of safety measures seemed doomed to complete obsolescence. However, as from 2004, the legislator unexpectedly enacted safety measures expressly labelled as such, and thus, disrupted the semantic unity implemented a decade earlier. In addition, the controversial notion of dangerousness was established as the ground of such measures. According to legal doctrine, this was a very “renewal of safety measures”. This formal reappearance of safety measures undoubtedly stems from circumstantial causes, owing to the political opportunity to depart from the penalty regime, especially in terms of application of law over time. Yet, it cannot be reduced to this single cause and also be explained by structural reasons pertaining to the nature of safety measures, which must be construed as a function i.e. the guarantee of the performance by a dangerous individual of his resocialisation obligation. This function may additionnally be expressed through various mechanisms: complementary penalties, measures of the pre-trial phase, conditions for serving sentences…Analysis shows that safety measures had not been discarded from criminal law and, instead of a“renewal”, the French legislator mostly extended their scope by multiplying the media of their function as guarantee.

It is important for any country to understand why its population makes certain choices on where to locate, since it can help to guide policy aimed at reviving deprived areas. Over the past few decades there has been a general trend for the population to migrate from the North to the South in England and Wales. Similarly, there has been an imbalance in the spread of new opportunities, with advanced services tending to locate in the South, particularly close London. This paper investigates whether changing employment patterns, away from manufacturing and towards services, has helped to facilitate migration within the England and Wales. There has been a distinct lack of empirical analysis in this area due to data limitations. Prior studies have had to utilise broad geographic regions in their analysis, providing limited insight into the reasons for such change. This paper aims to expand on these studies by looking at data on a more local level. This study made use of fixed panel regressions in order to estimate the effects of a region’s employment structure upon migration rates. The results indicate that neither the sector of employment, nor unemployment rates directly influence an individual’s likelihood to migrate. However, there is evidence to support the idea that population density influences migration, potentially as a result of agglomeration economies.

Three experiments were conducted to assess the potential for using Spanish goats to manage Gambel oakbrush winter range, dominated by Gambel oak (Quercus gambelii), for mule deer (Odocoileus hemionus). Summer- time food selection of goats, effects on plant community composition, and consequent effects on mule deer nutrition and foraging behavior were examined. An apparent preference for juvenile oak browse, and low use of oak twigs was observed. Selection for juvenile browse may have been facilitated by the retarded phenology of oak as compared to that of associated flora. This differential was maintained by repeated browsing. Animal performance, reflected in mass-specific gain rates, varied markedly. However, poor performance when observed, was not correlated with high juvenile oak content in diets. Goat browsing did not affect density of any shrub species. Stem size distributions changed in browsed oak populations only; skewness of these increased over time because of sprouting. Sprout weights increased in browsed oak populations, but declined in comparably browsed serviceberry (Amelanchier alnifolia) populations. The only other significant sprout response was a numerical increase in browsed snowberry (Symphoricarpos oreophilus) populations. Relationships between stem size and stem productivity in heavily browsed oak and serviceberry were characterized by lower slopes than those for adjacent control populations. Conversely, relationships in rabbitbrush (Chrvsothamnus viscidiflorus) populations, which were little used, were characterized by higher slopes than those for adjacent control populations. Sagebrush (Artemisia tridentata wvominqensis) production also responded positively, but via increased intercept. Browsing reduced productivity of both serviceberry and oak, but enhanced that of sagebrush. A positive production response was suggested for herbaceous species. Forage-base changes induced by goats caused wintering deer to increase the proportion of sagebrush in their diets under snow-covered conditions but not under snow-free conditions. Under snow-covered conditions, deer using goat-browsed pastures consumed diets higher in dry matter digestibility, but not protein, than those consumed by deer in control pastures. Dietary quality was unaffected by prior goat browsing under snow- free conditions. Furthermore, quality of diets consumed under snow-free conditions was not better than that consumed under snow-covered conditions.