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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Multitemporal mapping of burned areas  in mixed landscapes in eastern Zambia

Malambo, Lonesome 08 December 2014 (has links)
Fires occur extensively across Zambia every year, a problem recognized as a major threat to biodiversity. Yet, basic tools for mapping at a spatial and temporal scale that provide useful information for understanding and managing this problem are not available. The objectives of this research were: to develop a method to map the spatio-temporal seasonal fire occurrence using satellite imagery, to develop a technique for estimating missing data in the satellite imagery considering the possibility of change in land cover over time, and to demonstrate applicability of these new tools by analyzing the fine-scale seasonal patterns of landscape fires in eastern Zambia. A new approach for mapping burned areas uses multitemporal image analysis with a fuzzy clustering algorithm to automatically select spectral-temporal signatures that are then used to classify the images to produce the desired spatio-temporal burned area information. Testing with Landsat data (30m resolution) in eastern Zambia showed accuracies in predicting burned areas above 92%. The approach is simple to implement, data driven, and can be automated, which can facilitate quicker production of burned area information. A profile-based approach for filling missing data uses multitemporal imagery and exploits the similarity in land cover temporal profiles and spatial relationships to reliably estimate missing data even in areas with significant changes. Testing with simulated missing data from an 8-image spectral index sequence showed highly correlated (R2 of 0.78-0.92) and precise estimates (deviations 4-7%) compared to actual values. The profile-based approach overcomes the common requirement of gap-filling methods that there is gradual or no change in land cover, and provides accurate gap-filling under conditions of both gradual and abrupt changes. The spatio-temporal progression of landscape burning was evaluated for the 2009 and 2012 fire seasons (June-November) using Landsat data. Results show widespread burning (~ 60%) with most fires occurring late (August-October) in the season. Fire occurrence and burn patch sizes decreased with increasing settlement density and landscape fragmentation reflecting human influences and fuel availability. Small fires (< 5ha) are predominant and were significantly under-detected (>50%) by a global dataset (MODIS Burned Area Product (500m resolution)), underscoring the critical need of higher geometric resolution imagery such as Landsat imagery for mapping such fine-scale fire activity. / Ph. D.
32

Matilda, who told lies and was burned to death : ʼn vergelykende analise van die illustrasie van ʼn vermaan-verhaal

Visser, Carla 12 1900 (has links)
Thesis (MPhil)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: This study comprises a comparative visual analysis of three picture books, illustrated by Steven Kellogg, Posy Simmonds and Edward Gorey. The illustrators reinterpret the cautionary tale, Matilda, who told lies and was burned to death by Hilaire Belloc (1908). Not only does this study present a brief historical overview of the genre but it also interrogates the manner in which different styles of illustration underscore the pedagogical didactic narrative. The visual interpretations of these three illustrators are compared in order to establish whether or not they have succeeded in sustaining the subversive or grotesque elements of this cautionary tale. Belloc’s narrative as well as the illustrations are analysed in terms of gender. I discuss my own version of Belloc’s cautionary tale as a parody of this tale that serves to exaggerate the sometimes overt gendering of girl characters in cautionary tales. / AFRIKAANSE OPSOMMING: Hierdie skripsie behels die visuele analise van drie verskillende prenteboeke, onderskeidelik geillustreer deur Steven Kellogg, Posy Simmonds en Edward Gorey. Al drie illustreerders bied ʼn visuele herinterpretasie aan van die vermaan-vers Matilda, who told lies and burned to death deur Hilaire Belloc. Die skripsie bied nie net ʼn geskiedkundige oorsig oor die genre nie, maar ondersoek die manier waarop verskillende illustrasie-style die opvoedkundige, didaktiese narratief onderstreep. Die illustreerders se prenteboeke word vergelyk en daar word vasgestel of hulle daarin geslaag het om die subversiewe en selfs groteske elemente in hierdie vermaan-verhaal te behou. Belloc se narratief en die illustrasie daarvan is ook in terme van gender geanaliseer. Ek bespreek my eie weergawe van Belloc se vermaan-verhaal, wat ek aanbied as ʼn parodie om die soms duidelike “gendering” van meisie-karakters in vermaan-verhale te oordryf.
33

Da (i)licitude das queimadas da palha da cana-de-açúcar / About the (un)lawful of the burned sugar cane husk

Avolio, Ettore Geraldo 17 January 2003 (has links)
A queimada da palha da cana-de-açúcar como método preparatório à colheita é prática bastante polêmica e combatida, que está amparada por vários atos legislativos e conta com o apoio de setores dos três poderes constituídos. Contudo, esta proteção legislativa específica não outorga a ela a licitude, que é a harmonia com os princípios legais e sociais e com a aprovação da sociedade, que devem nortear qualquer lei e é necessária à sua subsistência. Neste trabalho é examinada a licitude das queimadas da palha da cana-de-açúcar, considerando diversos impactos que elas provocam no meio ambiente (flora, fauna, saúde humana, ar, água, solo, clima e meio de trabalho) e na economia. São analisados os argumentos favoráveis e contrários às queimadas, expostos por juízes, promotores de justiça, doutrinadores, entidades ambientais, pesquisadores, usineiros, cortadores de cana e profissionais de diversas áreas de interesse à matéria. Com a análise é possível concluir que a queimada da palha da cana-de-açúcar, apesar de sua econômica e social, é prática nociva ao meio ambiente e contrária a princípios sociais e legais relevantes e, por isso, deve ser reputada ilícita e não pode continuar a ser praticada. / Burned sugar cane husk as a harvest preparatory method is a very polemic and combated practice, although it is being sustained by many law acts and is supported by departments of the three Powers. However, this specific legislative protection doesn\'t award to this action the necessary lawful, which means having the harmony of the legal and social principals and the society approval, guiders of any law and its necessary support. At the present work the lawful for burned sugar cane husk is discussed considering its impacts over the environment (animals, plants, human health, air, water, soil, climate and working space) and on the economy. The arguments forward and against the burned sugar cane husk are examined through judicial decisions, public prosecutors actions, environmental entities, doctrines, scientists, the sugar cane workers and others involved with the subject. The conclusion is that burned sugar cane husk as a harvest preparatory method, even considering its economic and social importance, is a harmful practice to the environment and opposing to relevant social and legal principals and, therefore, has to be considered unlawful and also to be extinguished as a practice.
34

Efeitos da radiação laser em baixa intensidade na cicatrização de queimaduras de pele. Estudo Laser Doppler fluxométrico e histológico em ratos / Effects of low intensity laser radiation on burned skin healing. a laser doppler flowmetry and histological study in rats

Sugayama, Stella Thyemi 28 November 2006 (has links)
Queimaduras severas causam trauma às vítimas, pela perda de líquido corpóreo, injúria no sistema vascular cutâneo e demora na cicatrização das lesões. A irradiação com laser em baixa intensidade vem sendo estudada como tratamento alternativo, por ser uma terapia não-invasiva e capaz de acelerar o processo de cicatrização. O objetivo deste estudo foi avaliar os efeitos do laser de baixa potência (&lambda; = 660 nm) em queimaduras de pele por histomorfometria e fluxometria laser Doppler utilizando duas condições de irradiação. Trinta e seis animais com duas queimaduras criadas por vapor foram divididos em três grupos: no grupo dose fracionada (GF), as lesões foram irradiadas com dose de 1 J/cm2 nos dias 1, 3, 8 e 10; no grupo dose única (GU), as lesões foram irradiadas com dose de 4 J/cm2 no dia 1. O grupo controle (GC) não foi irradiado. O fluxo sanguíneo foi monitorado nos dias 3, 8, 10, 15 e 21 e três animais por grupo foram sacrificados nestes momentos. Os grupos irradiados mostraram um pico de vasos neoformados no dia 15, enquanto que o pico do GC foi no dia 21. O número de vasos no GC foi significantemente maior que GF e GU no dia 21. Com relação ao fluxo sangüíneo, os grupos irradiados mostraram um valor mais alto que o controle no dia 8, porém, sem diferenças significantes entre os grupos. Estes achados sugerem que o laser acelera a cicatrização de queimaduras, porém, sem diferenças significativas entre as doses estudadas. / Severe burn injuries cause extensive damage and are notoriously complicated by loss of body fluids, injury in the cutaneous vasculature and delayed wound healing. Low intensity laser therapy (LILT) has been studied as an alternative method since it is a non invasive treatment and is able to accelerate wound healing. The purpose of the present study was to evaluate the effects of LILT (&lambda; = 660 nm) in burned skin with two different doses by histomorphometry and laser Doppler flowmetry. Thirdy six male adult Wistar rats with two burns created on the back using water vapor were divided into 3 groups. In the fractioned dose laser group (GF), the lesions were irradiated with 1 J/cm2 on days 1, 3, 8 and 10; in the single dose laser group (GU), the lesions were irradiated with 4 J/cm2 on day 1. On control group (GC) lesions were not irradiated. The blood flow was measured on days 1, 3, 8, 10, 15 and 21 and three animals per group were sacrificed in these moments. Irradiated groups showed a peak of new blood vessels formation on day 15 while for GC the peak was on day 21. At this moment, the number of vessels in GC was significantly higher than GF and GS. Regarding to blood flux, irradiated groups displayed a higher value than GC on day 8, though no significant differences were observed. These findings suggest that LILT may accelerate skin repair, however, no significant differences were observed between the studied doses.
35

O impacto do monitoramento terapêutico de antimicrobianos sobre o tratamento e mortalidade intra-hospitalar de pacientes em uma UTI de queimados / Therapeutic drug monitoring of antimicrobial treatment and mortality in-hospital mortality in Burn Intensive Care Unit (ICU)

Machado, Anna Silva 31 August 2016 (has links)
Introdução: Em pacientes críticos, como os grandes queimados, todos os parâmetros farmacocinéticos (absorção, distribuição, metabolismo e excreção) de muitas classes de drogas, incluindo antimicrobianos, estão alterados. Devido à forte associação entre a terapia antimicrobiana adequada em pacientes com queimaduras e mortalidade, intervenções como o monitoramento terapêutico de drogas podem ser uteis para otimizar a concentração sérica desses agentes em diferentes estágios do estado hiperdinâmico. Portanto, é possível melhorar desfecho clínico e sobrevivência além de reduzir o desenvolvimento de resistência. O objetivo deste estudo foi analisar o impacto em mortalidade de uma estratégia de ajuste de dose de acordo com o monitoramento terapêutico e modelagem farmacocinética/farmacodinâmica em pacientes de uma Unidade de Terapia Intensiva (UTI) para Queimados. Métodos: Um estudo comparativo, retrospectivo, foi conduzido entre pacientes admitidos com pneumonia, infecção em queimadura, infecção de corrente sanguínea e/ou infecção do trato urinário associados à assistência à saúde em uma UTI para Queimados do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). Estes pacientes foram divididos em dois grupos: aqueles admitidos de maio de 2005 a outubro de 2008 que receberam antibioticoterapia em regime de dose convencional proposto pelo Grupo de Controle de Infecção Hospitalar do HC-FMUSP e aqueles admitidos de novembro de 2008 a junho de 2011 que receberam terapia antimicrobiana com dose ajustada de acordo com o monitoramento plasmático e modelagem farmacocinética. Características gerais dos dois grupos foram analisadas e desfechos clínicos (melhora dos sinais e sintomas da infecção), mortalidade em 14 dias e mortalidade hospitalar foram comparados. Resultados: 63 pacientes admitidos na UTI de Queimados apresentaram os critérios de inclusão para o grupo de tratamento convencional e 77 para o grupo de tratamento monitorado. Comparando dois grupos homogêneos em suas características gerais, houve diferenças quanto ao número de desbridamentos realizados e história de alcoolismo e uso de drogas ilícitas, mais frequentes no grupo de tratamento monitorado. Melhora clínica ocorreu em 56% dos pacientes sob regime monitorado e a mortalidade hospitalar foi similar entre os grupos. Pertencer a um dos grupos de tratamento não afetou o prognóstico. Na análise multivariada final, variáveis significativamente associadas com mortalidade hospitalar foram superfície corporal queimada maior que 30%, idade mais avançada e sexo masculino. Conclusão: Nosso estudo demonstrou que a estratégia de monitoramento terapêutico de antimicrobianos não alterou prognóstico de pacientes queimados. Acreditamos que são necessários mais estudos para embasar esta estratégia / Introduction: In critical patients, such as burn patients, pharmacokinetic parameters (absorption, distribution, metabolism and excretion) of many classes of drugs, including antibiotics, are altered. The aim of this study was to compare two groups of burned patients under treatment for healthcare associated infections with and without therapeutic drug monitoring (TDM) based on PK/PD modeling. Methods: A comparative study was conducted with patients with healthcare-associated pneumonia, burn infection, bloodstream infection and urinary tract infection in the Burn Intensive Care Unit (ICU) of a tertiary-care hospital. These patients were divided into two groups: 1) those admitted from May 2005 to October 2008 who received conventional antimicrobial dose regimen; and 2) those admitted from November 2008 to June, 2011 who received antibiotics with doses adjusted according to plasma monitoring and pharmacokinetics modeling. General characteristics of the groups were analyzed and clinical outcomes, 14-day and in-hospital mortality. Results: 63 patients formed the conventional treatment group and 77 the monitored treatment group. The groups were very homogeneous. Improvement occurred in 56% of the patients under monitored treatment and the in-hospital mortality was similar between groups. In the final multivariate models, variables significantly associated with in-hospital mortality were total burn surface area (TBSA) > 30%, older age and male sex. Treatment group did not affect the prognosis. Conclusions: TDM for antimicrobial treatment did not alter the prognosis of burn patients. More trials are needed to support the use of TDM to optimize treatment in burn patients
36

Dynamique de la végétation des savanes en lien avec l’usage des feux à Madagascar : analyse par série temporelle d’images de télédétection / Multiscale analysis of spatio-temporal vegetation dynamics using remote sensing data : application to the malagasy landscapes

Jacquin, Anne 07 July 2010 (has links)
Bien que le feu soit reconnu comme un facteur d’influence dans la dynamique de végétation des savanes, son rôle n’est pas clairement défini. Cette thèse aborde le problème de l’étude de la relation entre l’usage des feux et la dynamique de végétation. L’approche choisie repose sur l’analyse de séries temporelles d’images de télédétection à moyenne résolution spatiale. Les savanes étudiées sont situées sur le bassin versant de Marovoay au nord-ouest de Madagascar. Dans la mesure où il n’existe pas de consensus quant aux méthodes à utiliser, les savanes de Madagascar offrent un contexte particulier, en raison de la dégradation très prononcée du couvert végétal et des changements recherchés, pour tester les méthodes existantes et en proposer des nouvelles. Le premier objectif de ce travail est d’identifier le régime des feux à travers le suivi des variations spatio-temporelles des surfaces brûlées en milieu de savane. Pour cela, une méthode de cartographie des surfaces brûlées a été développée : elle est basée sur le calcul d’un indicateur annuel indiquant le passage d’un feu pendant la saison sèche et d’un indicateur saisonnier traduisant la période de passage du feu. Cette méthode, appliquée au site d’étude, a permis de produire une série temporelle de données utilisées pour caractériser le régime des feux à partir de deux paramètres, la période d’occurrence et la fréquence de passage du feu. En parallèle, le deuxième objectif consiste à caractériser la dynamique de végétation par l’analyse des variations spatio-temporelles de l’activité végétale. Deux approches de détection des changements, basées sur le traitement de série temporelle de NDVI, ont été testées. La première repose sur l’analyse des variations inter annuelles d’un indicateur phénologique traduisant l’activité végétale pendant la phase de croissance des savanes. La deuxième utilise une technique de décomposition temporelle pour extraire la tendance d’une série de NDVI. Dans les deux cas, les résultats ont permis de caractériser la dynamique de végétation à travers trois classes d’évolution de l’activité végétale (séries progressive, régressive ou stable). Ces résultats ont été évalués par comparaison avec ceux issus de techniques de détection des changements basées sur l’analyse diachronique d’images à haute résolution spatiale. Enfin, dans la dernière étape du travail, nous avons étudié les relations entre les informations relatives aux régimes des feux et à la dynamique de végétation en utilisant des modèles de régression multivariée. L’objectif est d’estimer l’importance et le rôle du feu dans la dynamique de végétation. Les résultats ont amené à trois conclusions : a) Le feu est un facteur de maintien des savanes ; b) Dans les situations où la pression liée aux activités anthropiques est faible, le feu, en particulier par la fréquence de son usage, est un facteur déterminant de la dynamique de végétation ; c) Dans les autres situations, l’interprétation des résultats est complexe et difficile, très certainement en raison de l’interaction de multiples facteurs anthropiques. / Fire is recognized to be an essential factor that explains savanna vegetation dynamics. But its role is not clearly defined. This work investigates the problem of studying the relation between fire usage and vegetation dynamic. This is addressed through the analysis of time series of medium spatial resolution remotely sensed images. We studied the savanna localized on the Marovoay watershed, on the northwest part of Madagascar. As no consensus exists on the adapted methods, the savanna of Madagascar offers a particular context to test existing methods or develop new ones, because of the advanced vegetation cover degradation and the nature of change to be detected. The first objective of this work is to identify fire regime by analyzing the spatio-temporal variations of burned areas in savanna areas. To this end, a burned area mapping method was developed. It is based on the definition of an annual indicator, which indicates the occurrence of a fire during the dry season, and a seasonal indicator, which gives the information on the date of the fire event. Applied to the study site, this method has lead to the production of a time series of data used for the characterization of the fire regime through two parameters, the period of occurrence and the frequency of fire. In parallel, the second objective consists on characterizing vegetation dynamic by monitoring spatiotemporal variations of vegetation activity. Two change detection approaches based on NDVI time series, were tested. The first consists on analyzing the inter annual variations of a phenological indicator related to vegetation activity during the active growth season. The second uses a temporal decomposition technique to extract the trend from an NDVI time series. In both cases, the vegetation dynamic is characterized through three classes linked to the evolution of the vegetation activity (progressive, regressive or stable series). Results were evaluated by a comparison with the results obtained from a diachronic change detection technique based of high spatial resolution images. Finally, in the last part of this work, we investigated the relation between fire regimes and vegetation activity change classes using multivariate regression models. The objective is to analyze to determine the importance and the role of fire into the vegetation dynamic. Results leaded to three conclusions: a) Fire is a factor that maintains savanna; b) In areas where pressure due to anthropogenic activities is low, fire frequency represents a determinant factor to explain vegetation dynamic; c) In others areas, the interpretation of results appears to be complex and difficult, probably because of the high level of interactions between multiple environmental factors.
37

Da (i)licitude das queimadas da palha da cana-de-açúcar / About the (un)lawful of the burned sugar cane husk

Ettore Geraldo Avolio 17 January 2003 (has links)
A queimada da palha da cana-de-açúcar como método preparatório à colheita é prática bastante polêmica e combatida, que está amparada por vários atos legislativos e conta com o apoio de setores dos três poderes constituídos. Contudo, esta proteção legislativa específica não outorga a ela a licitude, que é a harmonia com os princípios legais e sociais e com a aprovação da sociedade, que devem nortear qualquer lei e é necessária à sua subsistência. Neste trabalho é examinada a licitude das queimadas da palha da cana-de-açúcar, considerando diversos impactos que elas provocam no meio ambiente (flora, fauna, saúde humana, ar, água, solo, clima e meio de trabalho) e na economia. São analisados os argumentos favoráveis e contrários às queimadas, expostos por juízes, promotores de justiça, doutrinadores, entidades ambientais, pesquisadores, usineiros, cortadores de cana e profissionais de diversas áreas de interesse à matéria. Com a análise é possível concluir que a queimada da palha da cana-de-açúcar, apesar de sua econômica e social, é prática nociva ao meio ambiente e contrária a princípios sociais e legais relevantes e, por isso, deve ser reputada ilícita e não pode continuar a ser praticada. / Burned sugar cane husk as a harvest preparatory method is a very polemic and combated practice, although it is being sustained by many law acts and is supported by departments of the three Powers. However, this specific legislative protection doesn\'t award to this action the necessary lawful, which means having the harmony of the legal and social principals and the society approval, guiders of any law and its necessary support. At the present work the lawful for burned sugar cane husk is discussed considering its impacts over the environment (animals, plants, human health, air, water, soil, climate and working space) and on the economy. The arguments forward and against the burned sugar cane husk are examined through judicial decisions, public prosecutors actions, environmental entities, doctrines, scientists, the sugar cane workers and others involved with the subject. The conclusion is that burned sugar cane husk as a harvest preparatory method, even considering its economic and social importance, is a harmful practice to the environment and opposing to relevant social and legal principals and, therefore, has to be considered unlawful and also to be extinguished as a practice.
38

Efeitos da radiação laser em baixa intensidade na cicatrização de queimaduras de pele. Estudo Laser Doppler fluxométrico e histológico em ratos / Effects of low intensity laser radiation on burned skin healing. a laser doppler flowmetry and histological study in rats

Stella Thyemi Sugayama 28 November 2006 (has links)
Queimaduras severas causam trauma às vítimas, pela perda de líquido corpóreo, injúria no sistema vascular cutâneo e demora na cicatrização das lesões. A irradiação com laser em baixa intensidade vem sendo estudada como tratamento alternativo, por ser uma terapia não-invasiva e capaz de acelerar o processo de cicatrização. O objetivo deste estudo foi avaliar os efeitos do laser de baixa potência (&lambda; = 660 nm) em queimaduras de pele por histomorfometria e fluxometria laser Doppler utilizando duas condições de irradiação. Trinta e seis animais com duas queimaduras criadas por vapor foram divididos em três grupos: no grupo dose fracionada (GF), as lesões foram irradiadas com dose de 1 J/cm2 nos dias 1, 3, 8 e 10; no grupo dose única (GU), as lesões foram irradiadas com dose de 4 J/cm2 no dia 1. O grupo controle (GC) não foi irradiado. O fluxo sanguíneo foi monitorado nos dias 3, 8, 10, 15 e 21 e três animais por grupo foram sacrificados nestes momentos. Os grupos irradiados mostraram um pico de vasos neoformados no dia 15, enquanto que o pico do GC foi no dia 21. O número de vasos no GC foi significantemente maior que GF e GU no dia 21. Com relação ao fluxo sangüíneo, os grupos irradiados mostraram um valor mais alto que o controle no dia 8, porém, sem diferenças significantes entre os grupos. Estes achados sugerem que o laser acelera a cicatrização de queimaduras, porém, sem diferenças significativas entre as doses estudadas. / Severe burn injuries cause extensive damage and are notoriously complicated by loss of body fluids, injury in the cutaneous vasculature and delayed wound healing. Low intensity laser therapy (LILT) has been studied as an alternative method since it is a non invasive treatment and is able to accelerate wound healing. The purpose of the present study was to evaluate the effects of LILT (&lambda; = 660 nm) in burned skin with two different doses by histomorphometry and laser Doppler flowmetry. Thirdy six male adult Wistar rats with two burns created on the back using water vapor were divided into 3 groups. In the fractioned dose laser group (GF), the lesions were irradiated with 1 J/cm2 on days 1, 3, 8 and 10; in the single dose laser group (GU), the lesions were irradiated with 4 J/cm2 on day 1. On control group (GC) lesions were not irradiated. The blood flow was measured on days 1, 3, 8, 10, 15 and 21 and three animals per group were sacrificed in these moments. Irradiated groups showed a peak of new blood vessels formation on day 15 while for GC the peak was on day 21. At this moment, the number of vessels in GC was significantly higher than GF and GS. Regarding to blood flux, irradiated groups displayed a higher value than GC on day 8, though no significant differences were observed. These findings suggest that LILT may accelerate skin repair, however, no significant differences were observed between the studied doses.
39

O impacto do monitoramento terapêutico de antimicrobianos sobre o tratamento e mortalidade intra-hospitalar de pacientes em uma UTI de queimados / Therapeutic drug monitoring of antimicrobial treatment and mortality in-hospital mortality in Burn Intensive Care Unit (ICU)

Anna Silva Machado 31 August 2016 (has links)
Introdução: Em pacientes críticos, como os grandes queimados, todos os parâmetros farmacocinéticos (absorção, distribuição, metabolismo e excreção) de muitas classes de drogas, incluindo antimicrobianos, estão alterados. Devido à forte associação entre a terapia antimicrobiana adequada em pacientes com queimaduras e mortalidade, intervenções como o monitoramento terapêutico de drogas podem ser uteis para otimizar a concentração sérica desses agentes em diferentes estágios do estado hiperdinâmico. Portanto, é possível melhorar desfecho clínico e sobrevivência além de reduzir o desenvolvimento de resistência. O objetivo deste estudo foi analisar o impacto em mortalidade de uma estratégia de ajuste de dose de acordo com o monitoramento terapêutico e modelagem farmacocinética/farmacodinâmica em pacientes de uma Unidade de Terapia Intensiva (UTI) para Queimados. Métodos: Um estudo comparativo, retrospectivo, foi conduzido entre pacientes admitidos com pneumonia, infecção em queimadura, infecção de corrente sanguínea e/ou infecção do trato urinário associados à assistência à saúde em uma UTI para Queimados do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). Estes pacientes foram divididos em dois grupos: aqueles admitidos de maio de 2005 a outubro de 2008 que receberam antibioticoterapia em regime de dose convencional proposto pelo Grupo de Controle de Infecção Hospitalar do HC-FMUSP e aqueles admitidos de novembro de 2008 a junho de 2011 que receberam terapia antimicrobiana com dose ajustada de acordo com o monitoramento plasmático e modelagem farmacocinética. Características gerais dos dois grupos foram analisadas e desfechos clínicos (melhora dos sinais e sintomas da infecção), mortalidade em 14 dias e mortalidade hospitalar foram comparados. Resultados: 63 pacientes admitidos na UTI de Queimados apresentaram os critérios de inclusão para o grupo de tratamento convencional e 77 para o grupo de tratamento monitorado. Comparando dois grupos homogêneos em suas características gerais, houve diferenças quanto ao número de desbridamentos realizados e história de alcoolismo e uso de drogas ilícitas, mais frequentes no grupo de tratamento monitorado. Melhora clínica ocorreu em 56% dos pacientes sob regime monitorado e a mortalidade hospitalar foi similar entre os grupos. Pertencer a um dos grupos de tratamento não afetou o prognóstico. Na análise multivariada final, variáveis significativamente associadas com mortalidade hospitalar foram superfície corporal queimada maior que 30%, idade mais avançada e sexo masculino. Conclusão: Nosso estudo demonstrou que a estratégia de monitoramento terapêutico de antimicrobianos não alterou prognóstico de pacientes queimados. Acreditamos que são necessários mais estudos para embasar esta estratégia / Introduction: In critical patients, such as burn patients, pharmacokinetic parameters (absorption, distribution, metabolism and excretion) of many classes of drugs, including antibiotics, are altered. The aim of this study was to compare two groups of burned patients under treatment for healthcare associated infections with and without therapeutic drug monitoring (TDM) based on PK/PD modeling. Methods: A comparative study was conducted with patients with healthcare-associated pneumonia, burn infection, bloodstream infection and urinary tract infection in the Burn Intensive Care Unit (ICU) of a tertiary-care hospital. These patients were divided into two groups: 1) those admitted from May 2005 to October 2008 who received conventional antimicrobial dose regimen; and 2) those admitted from November 2008 to June, 2011 who received antibiotics with doses adjusted according to plasma monitoring and pharmacokinetics modeling. General characteristics of the groups were analyzed and clinical outcomes, 14-day and in-hospital mortality. Results: 63 patients formed the conventional treatment group and 77 the monitored treatment group. The groups were very homogeneous. Improvement occurred in 56% of the patients under monitored treatment and the in-hospital mortality was similar between groups. In the final multivariate models, variables significantly associated with in-hospital mortality were total burn surface area (TBSA) > 30%, older age and male sex. Treatment group did not affect the prognosis. Conclusions: TDM for antimicrobial treatment did not alter the prognosis of burn patients. More trials are needed to support the use of TDM to optimize treatment in burn patients
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Apports de la télédétection globale pour la caractérisation et modélisation du régime des incendies au Brésil : vers une approche des patchs de feux / Benefits of global remote sensing burned area for characterizing and modelling fire regimes in Brazil : towards a fire-patch level approach

Messias Pereira Nogueira, Joana 13 December 2016 (has links)
Les incendies sont des perturbations intrinsèques au fonctionnement des écosystèmes agissant sur la distribution des espèces, les cycles biogéochimiques et les interactions biosphère/atmosphère. La distribution spatiale et temporelle des surfaces brûlées résulte principalement d'un compromis entre la disponibilité en biomasse combustible et son état hydrique. Ainsi, caractériser et modéliser un régime d'incendie repose donc sur une évaluation principalement de la saisonnalité et l'intensité de la sécheresse. Dans les écosystèmes fortement soumis aux incendies comme les savanes, biome le plus affecté au niveau global, les informations disponibles ne sont issues que des observations issues de la télédétection globale. Malgré que ces types de données ont été largement utilisés depuis les années 2000 pour la quantification des émissions de carbone par les modèles globaux, les incertitudes restent grandes entre les différents produits mis à la disposition des scientifiques. De même les processus utilisés dans la modélisation dynamique des surfaces incendiées, couplés aux modèles de végétation repose sur des équations empiriques de quantification de la sécheresse. Pour des écosystèmes comme les savanes du Brésil, où les informations incendies sont uniquement obtenues par les informations issues de la télédétection globale, et où la variabilité des types fonctionnels de la végétation affecte le bilan hydrique des sols, évaluer les incertitudes sur ces variables est un pré requis important pour une modélisation appropriée des processus. Cette thèse aborde donc la caractérisation de la variabilité saisonnière des incendies et ses incertitudes dans les différents biomes du Brésil à partir des principales sources d'information sur les surfaces brulées issues de la télédétection globale (GFED4, GFED4s, MODIS MCD45A1, ESAFIRECCI) et des principaux indicateurs de sécheresse développés par les différents services forestiers. La même analyse est aussi appliquée aux surfaces incendiées issues des principaux modèles globaux de dynamique de végétation (DGVM) couplés avec un modèle incendie, afin d'identifier si les relations feux/sécheresse observées sur les produits satellitaires étaient conservées dans le modèles globaux. Après une analyse des processus utilisés dans les DGVMs, et notamment les nouveaux développements sur la caractérisation des patches de feux, la deuxième partie de mon travail a cherché à évaluer la capacité des produits globaux issus de la télédétection à méso-échelle (500m) à conserver la morphologie des patchs de feux observés à résolution plus fine pour une utilisation dans la caractérisation du régime des incendies et l'évaluation des DGVMs. La dernière partie de ce travail utilise une approche de biogéographie fonctionnelle basé sur les traits morphologiques des feux pour décrire un assemblage d'événements incendies et les comparer entre différents produits de télédétection pour en évaluer leurs similitudes ou leurs différences, ou entre différents biomes pour une nouvelle approche de pyrogéographie comparative / Fires are intrinsic disturbances in ecosystems functioning, and affecting species distribution, biogeochemical cycles and biosphere/atmosphere interactions. The spatial and temporal pattern of burnt areas is mainly the consequence of a compromise between fuel biomass availability and its water status. Characterizing and modelling a fire regime then relies on a reliable spatial and temporal evaluation of mainly seasonality and intensity of drought. In fire-prone ecosystems as savannas, the most fire affected biome globally, the only available information on burnt areas are derived from global remote sensing. Despite this information has been widely used for a global assessment of carbon emissions from fires since 2000, uncertainties remain important among data sources available for the scientific community. As well, processes used in the dynamic modelling of burned areas, embedded in vegetation models, are based on empirical equations quantifying the seasonal pattern of drought. For ecosystems like Brazilian savannas where fire information only rely on global remote sensing products, and where the variability in vegetation functional types affects the soil water budget, evaluating uncertainties on these variables is a prerequisite for an adequate modelling of processes. This thesis then aimed at characterizing the fire seasonality and the associated uncertainties in the different Brazilian biomes based on the main sources of global burned area (GFED4, GFED4s, MODIS MCD45A1, ESA FIRECCI) and a panel of drought indices developed by forest services worldwide. This thesis also investigated the same relationships analysis but with burned areas derived from the major dynamic global vegetation models (DGVM) coupled with fire modules, in order to test whether the burned area/drought relationships based on remote sensing are conserved in global models. After a review of the main processes computed in DGVMs, and particularly the new developments on the characterization of fire patches, the second part of this research aimed at evaluating the ability of global remote sensing products at 500m resolution to conserve patch morphologies captured at finer resolutions, for better characterizing fire regimes and evaluate DGVMs performances. The last part of this work used a functional biogeography approach based on fire morphological traits to describe an assemblage of fire events and to compare them between different remote sensing products, in order to evaluate their similarities and discrepancies, or between biomes for a new approach of comparative pyrogeography.

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