Hypolimnetic anoxia can result in higher internal phosphorus (P) loads from the sediments to the water column, thereby increasing nutrient availability, making preventing anoxia a major goal for lake managers to improve water quality. Side-stream saturation (SSS), a type of hypolimnetic oxygenation system, has been developed to maintain oxygenated conditions at the sediments by withdrawing oxygen-depleted water from the hypolimnion to an on-site facility and injecting it with oxygen under high pressure before returning it to the hypolimnion. While this technique has been studied in select water bodies, to date it has not been successfully deployed in a shallow lake. This study investigated the effects of an SSS system deployed at Falling Creek Reservoir, a shallow drinking water reservoir located in Vinton, Virginia, USA. Specifically, we examined the effects of the SSS system on several chemical, physical, and biological response variables to ascertain the short-term impacts of hypolimnetic oxygenation on reservoir water quality. We found that the SSS system was successful in increasing dissolved oxygen concentrations in the reservoir hypolimnion without weakening stratification, warming the sediments, or increasing turbidity; however, we were unable to detect any short-term effects of SSS operation on P concentrations, P loading, pH, chlorophyll a, or algal density. Interestingly, we also observed an increase in oxygen demand in response to SSS operation, which must be taken into account when deploying oxygenation systems in the future. Continued monitoring is necessary to more completely assess the long-term impacts of SSS operation on water quality at Falling Creek Reservoir. / Master of Science

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Made available in DSpace on 2016-08-17T13:54:03Z (GMT). No. of bitstreams: 1 DissertacaoPAULOCESARGARRESILVA2015.pdf: 892844 bytes, checksum: 5a390d547ede9bb52b7a324549e007ae (MD5) Previous issue date: 2015-03-31 / Ce travail analyse le rapport entre stratification sociale, scolaire et lingüistique dans le processus de reproduction ou transformation sociale. Pour ce faire il trouve ses fondements épistémologiques dans la sociolingüistique de Labov, et les travaux de Foucault, Benerstein et Bourdieu, entre autres. Il se place dans une perspective d analyse qualitative, en sachant que l importance de données colligées ne se justifie pas par la quantité des individus interrogés mais par la richesse et pour ce que les informations founies représentent, permettant établir des rapports et élargir les inférences sur un plan plus général. Les données ont été construits par le moyen des questionnaires dirigés aux étudiants de la troisième année du lycée dans des écoles publiques et privés dans la ville de São Luis du Maranhão (Brésil). Il soutient que le rapport entre langue et société est intrinsèque étant donné qu on ne peut pas dissocier la langue de son contexte social de production dont la force symbolique dépend de la position sociale que celui qui parle occupe dans la structure sociale. Le cadre lingüistique change dans la mesure que change la position sociale. L appropriation des codes lingüistiques est une condition nécessaire pour participer des rapports sociaux de pouvoir. Cependant, il y a un contrôle des codes lingüistiques qui rend inaccessible aux groupes sociaux défavorisés. L éducation serait est une forme politique de surmonter ce contrôle, mais elle deviant un mécanisme de contrôle qui favorise, en quelque sorte, une ritualisation des discours. Les variables telles que : lieux de naissance, residence, profession et scolarité des parents, l habitus culturel des étudiants, sont autant des índices qui rendent possibles d établir les rapports entre stratification sociale, stratification scolaire et lingüistique en montrant que les facteurs socioculturels et économiques ont des rapports étroits avec le développement scolaire et lingüistique des étudiants. Dans une societé où il y a une varieté de stratification, notamment une stratification scolaire, qui deviant une cause eficiente de reproduction sociale et de conservation du pouvoir des groupes dominants, on ne peut pas la considérer comme une société démocratique. Ce travail veut contribuer avec la réflexion et l entendement des processus des rapports de pouvoir dans les conflits sociaux. En plus, il montre que l éducation n est pas à l écart des conflits sociaux, et que l enseignant en tant qu un élément du processus éducatif est un agent de reproduction ou transformation sociale. De ce fait, la pratique pédagogique, ne peut pas être dépourvue d une critique sociale. / O presente trabalho analisa a correlação entre a estratificação social, escolar e linguística no processo de reprodução ou transformação social. Para tanto, ele encontra seus fundamentos epistemológicos na sociolinguística de Labov e nas contribuições de Foucault, Bernstein, Bourdieu, entre outros. Ele adota uma metodologia de análise qualitativa, sendo que a importância dos dados coletados não se justifica pela quantidade dos indivíduos entrevistados, mas pela riqueza e capacidade representativa dos dados fornecidos, os quais permitem tecer relações e ampliar as inferências para um contexto mais generalizado. Os dados foram construídos por meio de entrevistas gravadas e questionários direcionados aos estudantes da 3ª série do ensino médio de escolas públicas e privadas de São Luís. Defende-se que a relação entre língua e sociedade é intrínseca, uma vez que não se pode dissociar a língua de seu contexto de produção, uma vez que sua força simbólica depende da posição social que o falante ocupa na estrutura social. À medida que o falante muda de posição social, seu padrão linguístico, também, muda. A aquisição do código linguístico é condição fundamental para que o falante participe das relações sociais de poder, porém há formas de controle do código linguístico que o torna inacessível aos falantes dos grupos sociais desprestigiados. A educação seria uma forma política para superar esse controle, porém ela se torna um mecanismo de controle que favorece, em certo sentido, um processo de ritualização da palavra. As variáveis, tais como: local de nascimento, de residência, profissão e escolaridade dos pais e mães, habitus cultural dos estudantes, etc. são indicadores que possibilitam relacionar a estratificação social, estratificação escolar e a linguística mostrando que os fatores socioculturais e econômicos têm relação com o desenvolvimento escolar e linguístico dos estudantes. Numa sociedade em que há várias formas de estratificação, em especial a estratificação escolar, a qual é uma forma eficiente de reprodução social e manutenção do poder pelos grupos dominantes, não pode ser considerada, de fato, uma sociedade democrática. Assim, espera-se contribuir com a reflexão e o entendimento sobre os processos sociais e as relações de poder inerentes aos conflitos sociais. Além disso, mostra-se que a educação não está fora desses conflitos e que o professor, como elemento fundamental do processo educativo, é um agente de reprodução ou transformação social, por isso a sua prática pedagógica não pode ser desprovida de uma crítica social.

Twentieth-century scholarship on the social composition of the Pauline communities has focused on a binary model of the social structure of Roman society that posits a very small group of the élites and an enormous group of the non-élites. More recently, studies have tried to differentiate between strata within the non-élite groups by qualitatively identifying their economic conditions and quantitatively estimating the percentage distribution of each stratum. However, the major problem has been the lack of an economic reference line or a “poverty line” that would enable the meaningful comparison of different standards of living among the urban non-élites. This thesis aims to examine the economic strata of the non-élites in Roman society in the first century CE and estimates their standards of living by clarifying and establishing the concept of subsistence as an economic point of reference. This study first surveys the history of research on the social position of the earliest Christians in order to understand the debates of the twentieth century and the last decade. Then, the two levels of basic needs that are embedded in the concept of subsistence are explored and estimated: the “survival standard” and the “subsistence standard”. The former is more scientifically defined, while the latter focuses on aspects of social provision. The survival standard in the urban settings of the first century CE is used as a baseline to measure and compare the standards of living of various strata of non-élite groups such as unskilled workers, slaves, ordinary artisans, traders and professional artisans. Finally, once the economic stratification of the urban non-élites and their respective standards of living have been established, this framework is applied to the Pauline communities in Thessalonica, Philippi and Corinth in order to explain the issues of poverty, charity and wealth in the letters.

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In this thesis a case of advection fog over the Baltic Sea is studied. The period examined is from June 5th to 7th 1995. Data is taken from the instrumented mast, situated on the island Östergarnsholm, a small and flat island without trees outside of Gotland. From the measurements among others the heat flux, relative humidity and temperature are analyzed. In the evening June 5th 1995 the fog is advected in over Östergarnsholm. This can both be seen from the increasing relative humidity and the decreasing temperature. Before the fog arrived the boundary layer was stably stratified. This stratification quickly changed to neutral as the fog reaches Östergarnsholm. After careful evaluation the neutral stratification is shown not to be neutral at all. The stratification closest to the ground up to 15 meters is unstable and above the stratification is stable. From this the conclusion is made that the fog is low only 15 meters high during this period. At noon June 6th the air temperature decreases dramatically below the sea surface temperature at the same time as the relative humidity increases up to 100%. The fog is now thick enough to have most of the outgoing radiation coming from the top, which decreases the temperature a few degrees. As the stability is investigated it shows unstable stratification up to the highest level (28 meters). The assumption is made that the fog is at least 30 meters deep. Also the normalized standard deviations for temperature and vertical velocity are examined to find out if they behave as the variation in the undisturbed boundary layer.2 / Sammanfattning av ”Påverkan av dimma på skiktningen och turbulenta flöden över hav” I detta arbete studeras ett fall av advektions dimma över Östersjön. Perioden undersökt är från den 5 till den 7 juni 1995. Mätmasten står på ön Östergarnsholm, en liten och låg ö utan träd utanför Gotland. Ur mätningarna fås bl.a. värmeflödet, relativa fuktigheten och temperaturen. På kvällen den 5 juni 1995 advekteras dimman in över Östergarnsholm. Detta ses både från att relativa fuktigheten stiger och att temperaturen sjunker. Innan dimman anlände var gränsskiktet stabilt skiktat. Denna skiktning ändrades snabbt till neutral då dimman når fram. Denna till synes neutrala skiktning visade sig efter noggrannare undersökning att inte alls vara neutral. Skiktet närmast marken upp till 15 meters höjd visade sig vara instabilt och däröver var det stabilt. Utifrån detta dras slutsatsen att dimman är låg endast 15 meter hög under denna period. Vid 12 tiden på dagen den 6 juni sjunker lufttemperaturen dramatiskt under ytvatten temperaturen samtidigt som relativa fuktigheten stiger upp till 100 %. Dimman är nu så pass tjock att den största delen av utstrålningen sker ifrån toppen vilket sänker luft temperaturen flera grader. Då stabiliteten undersöks visar den sig vara instabil skiktad ända upp till högsta mät nivån (28 meter). Antagandet görs att dimman är minst 30 meter djup. Även normaliserad standard avvikelse för temperaturen och den vertikala hastigheten undersöks för att ta reda på om de uppvisar samma variation som i det ostörda gränsskiktet.