INTRODUÇÃO: O aprimoramento dos métodos de rastreamento e a conscientização da população geral contribuíram para o diagnóstico cada vez mais precoce do câncer de mama e proporcionou, juntamente com o avanço na terapêutica, altas taxas de sobrevida. O estado do acometimento axilar por metástase é um dos principais fatores prognósticos em pacientes com câncer de mama, particularmente naquelas com diagnóstico em estádio inicial. Na última década, esforços científicos foram direcionados para simplificar a amostragem dos linfonodos axilares, diminuindo a morbidade, mas respeitando os princípios oncológicos. Nesse sentindo, a biópsia do linfonodo sentinela foi considerada o avanço mais importante. Ao se obter um método preditor do estado axilar, que apresente os benefícios da abordagem padrão dissecção axilar e biópsia de linfonodo sentinela porém sem seus efeitos colaterais e que seja facilmente reproduzível, realizaremos um grande avanço na avaliação e terapêutica do câncer de mama inicial. MÉTODOS: Foi realizado estudo transversal retrospectivo com base nos prontuários de pacientes com câncer de mama invasivo, não metastático, com qualquer idade, atendidas entre 1999 e 2007 no Setor de Mastologia da Disciplina de Ginecologia do Departamento de Obstetrícia e Ginecologia da Faculdade de Medicina da Universidade de São Paulo e Clínica Professor José Aristodemo Pinotti, cujo estudo histopatológico e imunoistoquímico foi supervisionado por um único médico patologista. Realizamos uma subdivisão imunoistoquímica dos tumores, sendo considerado luminal A os tumores com receptores hormonais positivos e HER 2 negativo; luminal B os com receptores hormonais positivos e HER 2 positivo; HER 2 as pacientes com receptores hormonais negativos e HER 2 positivo e triplo negativo aquelas com receptores hormonais e HER 2 negativos. Correlacionamos esses subtipos com as variáveis clínicas idade e tamanho tumoral para predizer a probabilidade de acometimento linfonodal axilar. RESULTADOS: Duzentos e trinta e nove casos foram analisados. No subtipo luminal A, a possibilidade de metástase foi maior quanto menor a idade da paciente e maior o tamanho do tumor. Essa foi a única associação que apresentou diferença estatisticamente significante. As pacientes que possuíam tumores triplo negativo tiveram, aproximadamente, 90% menos chance de metástase linfonodal que as pacientes com tumor luminal A. CONCLUSÕES: As pacientes com tumor luminal A apresentaram, significativamente, maior probabilidade de metástase linfonodal axilar. As pacientes com de tumores triplo negativo, com idade superior a 55 anos ou tumores menores que 2 cm, revelaram menor probabilidade de metástase axilar / INTRODUTION: The improvement of screening methods and awareness of general population contributed to the increasingly early diagnosis of breast cancer and provided, together with advances in therapy, high survival rates. The status of axillary involvement is a major prognostic factor in patients with breast cancer, particularly those with early stage. In the last decade, research efforts were directed to simplify the sampling of axillary lymph nodes, decreasing the morbidity, but respecting the oncological principles. In this sense, the sentinel lymph node biopsy was considered the most important advance. If we obtain a method to predict the axillary status, with the benefits of the standard approach - axillary dissection and sentinel lymph node biopsy - without its side effects and easily reproducible, we will hold a major advance in the assessment and treatment of early breast cancer. METHODS: We conducted a retrospective cross-sectional study based on records of patients with invasive breast cancer, non metastatic, with any age, treated between 1999 and 2007 in the breast cancer Sector of the Gynecology Discilpine of the Department of Obstetrics and Gynecology, Faculty of Medicine, University of São Paulo and Private Clinic of Professor José Aristodemo Pinotti, whose histopathological studies were supervised by a single pathologist. We performed an immunohistochemical subdivision of the tumors, and considered luminal A tumors with positive hormonal receptors and negative HER 2, luminal B with positive hormonal receptors and positive HER 2, HER 2 patients with negative hormonal receptors and positive HER 2 and the triple-negative those with negative hormonal receptors and HER 2. Those subtypes were correlated with the clinical variables age and tumor size in predicting the likelihood of axillary lymph node involvement. RESULTS: Two hundred and nine cases were analyzed. In the luminal A, the possibility of axillary metastasis was higher in the younger patients and larger tumors. That was the only combination that showed statistically significant difference. The patients who had triplenegative tumors had approximately 90% less chance of lymph node metastasis than patients with tumors luminal A. CONCLUSIONS: The patients with luminal A tumors showed a significantly association with greater likelihood of axillary lymph node metastasis. The patients with triple negative tumors, age over 55 years or tumors smaller than 2 cm showed a lower likelihood of axillary lymph node metastasis

INTRODUÇÃO: O aprimoramento dos métodos de rastreamento e a conscientização da população geral contribuíram para o diagnóstico cada vez mais precoce do câncer de mama e proporcionou, juntamente com o avanço na terapêutica, altas taxas de sobrevida. O estado do acometimento axilar por metástase é um dos principais fatores prognósticos em pacientes com câncer de mama, particularmente naquelas com diagnóstico em estádio inicial. Na última década, esforços científicos foram direcionados para simplificar a amostragem dos linfonodos axilares, diminuindo a morbidade, mas respeitando os princípios oncológicos. Nesse sentindo, a biópsia do linfonodo sentinela foi considerada o avanço mais importante. Ao se obter um método preditor do estado axilar, que apresente os benefícios da abordagem padrão dissecção axilar e biópsia de linfonodo sentinela porém sem seus efeitos colaterais e que seja facilmente reproduzível, realizaremos um grande avanço na avaliação e terapêutica do câncer de mama inicial. MÉTODOS: Foi realizado estudo transversal retrospectivo com base nos prontuários de pacientes com câncer de mama invasivo, não metastático, com qualquer idade, atendidas entre 1999 e 2007 no Setor de Mastologia da Disciplina de Ginecologia do Departamento de Obstetrícia e Ginecologia da Faculdade de Medicina da Universidade de São Paulo e Clínica Professor José Aristodemo Pinotti, cujo estudo histopatológico e imunoistoquímico foi supervisionado por um único médico patologista. Realizamos uma subdivisão imunoistoquímica dos tumores, sendo considerado luminal A os tumores com receptores hormonais positivos e HER 2 negativo; luminal B os com receptores hormonais positivos e HER 2 positivo; HER 2 as pacientes com receptores hormonais negativos e HER 2 positivo e triplo negativo aquelas com receptores hormonais e HER 2 negativos. Correlacionamos esses subtipos com as variáveis clínicas idade e tamanho tumoral para predizer a probabilidade de acometimento linfonodal axilar. RESULTADOS: Duzentos e trinta e nove casos foram analisados. No subtipo luminal A, a possibilidade de metástase foi maior quanto menor a idade da paciente e maior o tamanho do tumor. Essa foi a única associação que apresentou diferença estatisticamente significante. As pacientes que possuíam tumores triplo negativo tiveram, aproximadamente, 90% menos chance de metástase linfonodal que as pacientes com tumor luminal A. CONCLUSÕES: As pacientes com tumor luminal A apresentaram, significativamente, maior probabilidade de metástase linfonodal axilar. As pacientes com de tumores triplo negativo, com idade superior a 55 anos ou tumores menores que 2 cm, revelaram menor probabilidade de metástase axilar / INTRODUTION: The improvement of screening methods and awareness of general population contributed to the increasingly early diagnosis of breast cancer and provided, together with advances in therapy, high survival rates. The status of axillary involvement is a major prognostic factor in patients with breast cancer, particularly those with early stage. In the last decade, research efforts were directed to simplify the sampling of axillary lymph nodes, decreasing the morbidity, but respecting the oncological principles. In this sense, the sentinel lymph node biopsy was considered the most important advance. If we obtain a method to predict the axillary status, with the benefits of the standard approach - axillary dissection and sentinel lymph node biopsy - without its side effects and easily reproducible, we will hold a major advance in the assessment and treatment of early breast cancer. METHODS: We conducted a retrospective cross-sectional study based on records of patients with invasive breast cancer, non metastatic, with any age, treated between 1999 and 2007 in the breast cancer Sector of the Gynecology Discilpine of the Department of Obstetrics and Gynecology, Faculty of Medicine, University of São Paulo and Private Clinic of Professor José Aristodemo Pinotti, whose histopathological studies were supervised by a single pathologist. We performed an immunohistochemical subdivision of the tumors, and considered luminal A tumors with positive hormonal receptors and negative HER 2, luminal B with positive hormonal receptors and positive HER 2, HER 2 patients with negative hormonal receptors and positive HER 2 and the triple-negative those with negative hormonal receptors and HER 2. Those subtypes were correlated with the clinical variables age and tumor size in predicting the likelihood of axillary lymph node involvement. RESULTS: Two hundred and nine cases were analyzed. In the luminal A, the possibility of axillary metastasis was higher in the younger patients and larger tumors. That was the only combination that showed statistically significant difference. The patients who had triplenegative tumors had approximately 90% less chance of lymph node metastasis than patients with tumors luminal A. CONCLUSIONS: The patients with luminal A tumors showed a significantly association with greater likelihood of axillary lymph node metastasis. The patients with triple negative tumors, age over 55 years or tumors smaller than 2 cm showed a lower likelihood of axillary lymph node metastasis

L’objectif de cette thèse est le diagnostic de l’état de santé de la lagune de Bizerte par une approche multi-marqueurs (chimique, biochimique et morphométrique) et multi-compartiments (sédiment et biote). Pour atteindre cet objectif, les modèles biologiques choisis sont la moule Mytilus galloprovincialis et le poisson gobie Zosterisessor ophiocephalus. Ces deux espèces sont largement répandues dans la lagune de Bizerte et la mer Méditerranée. Dans une première partie et afin d’estimer les niveaux de contamination de la lagune de Bizerte par les polluants organiques persistants (POPs), des analyses chimiques, granulométriques et minéralogiques (COT) de sédiments superficiels ont été réalisées. Par la suite la toxicité potentielle des sédiments a été évaluée par une batterie de bioessais. Dans une troisième partie la biodisponibilité et l’impact écotoxicologique des POPs étudiés ont été évalués par l’accumulation de ces contaminants au niveau des deux organismes indicateurs choisis et l’étude des réponses biologiques associées à travers quelques biomarqueurs tels que la catalase (CAT), l’acide thiobarbiturique (TBARS); l’Ethoxyrésorufine O-dééthylase (EROD); la glutathion-S-transférase (GST) et l'acétylcholinestérase (AChE). Les principaux résultats des analyses chimiques révèlent une contamination générale des sédiments et organismes étudiés par les POPs. Les niveaux de contamination sont fonction de l’espèce et de la station étudiée. La comparaison de nos valeurs avec les données de la littérature a montré que les niveaux de contamination de la lagune sont similaires ou légèrement inférieurs à ceux enregistrés dans des écosystèmes équivalents dans d’autres pays du monde. L’estimation de la toxicité des sédiments au moyen des valeurs guides sédimentaires (ERL, ERM, TEL et PEL) et trois tests biologiques (Microtox®, SOS-Chromotest® et test MELA) ont montré que les sédiments des stations du canal de Bizerte S1 et S3 représentent un danger accru pour les organismes aquatiques. Nos résultats ont montré que les biomarqueurs mesurés chez les deux espèces choisies sont des paramètres sensibles et inductibles permettant de qualifier l’état de santé des organismes et la qualité globale du milieu étudié. Les marqueurs morphométriques contrairement aux marqueurs biochimiques n’ont pas permis de discriminer les différents sites étudiés. Contrairement aux poissons, il a été démontré chez les moules que les facteurs abiotiques ont une influence sur les concentrations en POPs et les réponses des biomarqueurs.Au vu de l’ensemble de ces résultats, il apparaît que cette approche intégrative associant des mesures chimiques et écotoxicologiques représente un bon moyen pour évaluer la qualité de l’environnement notamment dans le cadre de programmes de biosurveillance. / The objective of this thesis was the diagnosis of the health status of the Bizerte lagoon using a multi-marker (chemical, biochemical and morphometric) and multi-compartment approach (sediment and biota). To achieve this objective, the selected biological models were the mussel Mytilus galloprovincialis and the goby fish Zosterisessor ophiocephalus. Both species are widespread in the Bizerte lagoon and the Mediterranean Sea. In a first part and in order to estimate the levels of contamination of the Bizerte lagoon, persistent organic pollutant (POPs), granulometric and mineralogical (TOC) analyses of surficial sediments were carried out. Afterwards, the potential toxicity of sediments was assessed by a battery of bioassays. In a the third part, bioavailability and ecotoxicological impact of POPs studied were assessed by bioaccumulation measurement in these two indicators species, and the study of biological responses associated through a battery of biomarkers such as catalase (CAT), thiobarbituric acid (TBARS); Ethoxyresorufin O-deethylase (EROD); glutathione-S-transferase (GST) and acetylcholinesterase (AChE). The main results of the chemical analyses show a general contamination of sediments and organisms studied by POPs. Contamination levels are dependent on the studied species and stations. Comparing our values with literature data, showed that the levels of contamination of the lagoon are similar or slightly lower than equivalent ecosystems in other parts of the world. Besides, the estimation of sediment toxicity, using sediment guideline values (ERL, ERM, TEL et PEL), as well as bioassays (Microtox®, SOS-Chromotest® and MELA test) showed that stations of canal of Bizerte S1 and S3 were associated with an increased hazard to aquatic organisms. Our results showed that biomarkers measured in both selected species are sensitive and inducible parameters, which allowed to characterize the health status of organisms and global quality of the studied environment. Biochemical but not morphometric markers allowed to discriminate the different studied sites according to chemical risk. Unlike fish, it has been demonstrated in mussels that abiotic factors influence the concentrations of POPs and biomarker responses.Obtained data suggest that integrative approach, combining chemical and ecotoxicological measurements, may represent a good way to asses the quality of the environment, particularly, in the context of biomonitoring programs.

L’expansion agricole ne cesse d’agir sur la perte d’habitats essentiels et nécessaires au développement des espèces. Bien que plusieurs espèces réussissent à survivre dans ces habitats peu adéquats, la persistance et la santé de plusieurs populations semblent compromises par l’utilisation souvent intensive de polluants chimiques agricoles et de fertilisants. Cette étude a pour but de déterminer l’impact des contaminants et de l’écologie du paysage sur la diversité génétique des populations de ouaouarons retrouvées en milieu agricole. Notre hypothèse de départ stipule qu’une exposition chronique aux polluants agricoles induira des différences génétiques au niveau des populations exposées. Le bassin versant de la rivière Yamaska a été désigné comme site d’étude puisqu’il fait partie de la région agricole la plus importante du Québec et parce qu’on y retrouve un gradient d’utilisation des terres pour l’agriculture (faible, moyen, élevé). Le ouaouaron a été choisi à titre de modèle biologique puisque ses caractéristiques physiologiques et écologiques en font une espèce sentinelle capable de rendre compte de l’état de santé global des écosystèmes. La caractérisation génétique des populations a été effectuée à partir de marqueurs d’AFLP (Amplified Fragment Length Polymorphism). Les résultats montrent que la diversité génétique est liée à la colonisation à partir de l’embouchure de la rivière Yamaska et que quelques populations sont génétiquement différenciées. De plus, nous avons démontré une relation positive entre le nombre de locus polymorphes et l’atrazine, l’indice de contamination et le métolachlore et la concentration en azote ainsi qu’entre l’hétérozygotie attendue et la concentration en phosphate. / Agricultural expansion continues to act on the loss of critical habitats for the development of species and affects the integrity of remaining habitats. Although several species manage to survive in such inadequate ecosystems, persistence and health of many populations seem compromised by the intensive use of pesticides and fertilizers. This study aims at determining the impact of pollutants and landscape ecology on the genetic diversity of bullfrog populations inhabiting an agricultural area. Our hypothesis states that chronic exposure to agricultural pollutants induces genetic differences in exposed populations. The watershed of the Yamaska River was designated as the study site because it is part of the largest agricultural region in Quebec and because the sampling sites represent a gradient of land use for agriculture (low, moderate, high). The bullfrog was chosen as the biological model, since its physiological and ecological characteristics make it a sentinel species, which can reflect the overall health of an ecosystem. Population genetic characterization has been conducted from AFLP (Amplified Fragment Length Polymorphism) markers. The results show that genetic diversity is correlated to colonization from the mouth of the Yamaska River and that some populations are genetically differentiated. Furthermore, we demonstrated a positive relationship between the number of polymorphic loci and the atrazine, the contamination index and the nitrogen concentration as well as between expected heterozygosity and phosphate concentration.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.

The goal of this research was to improve ocean colour chlorophyll a (Chla) retrievals in the coastal Case 2 waters of the Salish Sea by characterizing the main drivers of optical variability and using this information to parameterize empirical algorithms based on an optical classification. This was addressed with three specific objectives: (1) build a comprehensive spatio-temporal data set of in situ optical and biogeochemical parameters, (2) apply a hierarchical clustering analysis to classify above-water remote sensing reflectance (Rrs) and associated bio-optical regimes, (3) optimize and validate class-specific empirical algorithms for improved Chla retrievals. Biogeochemical and optical measurements, acquired at 145 sites, showed considerable variation; Chla (mean=1.64, range: 0.10 – 7.20 µg l-1), total suspended matter (TSM) (3.09, 0.82 – 20.69 mg l-1), and absorption by chromophoric dissolved organic matter (a_cdom (443)) (0.525, 0.007 – 3.072 m-1), thus representing the spatial and temporal variability of the Salish Sea. A comparable range was found in the measured optical properties; particulate scattering (b_p (650)) (1.316, 0.250 – 7.450 m-1), particulate backscattering (b_bp (650)) (0.022, 0.005 – 0.097 m-1), total beam attenuation coefficient (c_t (650)) (1.675, 0.371 – 9.537 m-1), and particulate absorption coefficient (a_p (650)) (0.345, 0.048 – 2.020 m-1). Empirical orthogonal function (EOF) analysis revealed 95% of the Rrs variance was highly correlated to b_p (r = 0.90), b_bp (r = 0.82), and TSM concentration (r = 0.80), suggesting a strong influence from riverine systems in this region. Hierarchical clustering on the normalized Rrs revealed four spectral classes. Class 1 is defined by high overall Rrs magnitudes in the red, indicating more turbid waters, Class 2 showed high Rrs values in the red and well defined fluorescence and absorption features, indicated by a high Chla and TSM presence, Class 3 showed low TSM influence and more defined Chla signatures, and Class 4 is characterized by overall low Rrs values, suggesting more optically clear oceanic waters. Spectral similarities justified a simplification of this classification into two dominant water classes – (1) estuarine class (Classes 1 and 2) and (2) oceanic class (Classes 3 and 4) – representing the dominant influences seen here. In situ Chla and above-water remote sensing reflectance measurements, used to validate and parameterize the OC3M/OC3S3, two-band ratio, FLH and, modified FLH (ModFLH) empirical algorithms, showed a systematic overestimation of low Chla concentrations and underestimation of higher Chla values for all four algorithms when tuned to regional data. FLH and ModFLH algorithms performed best for these data (R2 ~ 0.40; RMSE ~ 0.32). Algorithm accuracy was significantly improved for the class-specific parametrizations with the two-band ratio showing a strong correlation to the Chla concentrations in the estuarine class (R2 ~ 0.71; RMSE ~ 0.33) and the ModFLH algorithm in the oceanic class (R2 ~ 0.70; RMSE ~ 0.26). These results demonstrated the benefit of applying an optical classification as a necessary first step into improving Chla retrievals from remotely sensed data in the contrasted coastal waters of the Salish Sea. With accurate Chla information, the health of the Salish Sea can be viably monitored at spatial and temporal scales suitable for ecosystem management. / Graduate / 0416 / stephen.uvic@gmail.com

The thesis evaluates the results of experimental protocol involving the fertility sparing treatment procedure in early stage cervical carcinoma (LAP I protocol). Sentinel lymph node detection and experimental extirpation of afferent channels using laparoscopy and its technical aspects were analysed in prospective group of 85 women. The oncologic results and early/late morbidity show that established surgical procedures can be considered safe with minimal morbidity, provided that the indication criteria are met. The second part analyses the results of 148 women with no further pregnancy plans suffering from cervical tumors less than 2 cm in size with invasion less than half of the stroma (LAP II protocol). The oncological results in our defined group are very good and comparable to 'standard' procedure of modified radical hysterectomy type B or C with lower morbidity. In the separate section the thesis analyses the possibilities of laparoscopy in endometrial cancer treatment including the potentials of use of sentinel lymph node detection and technical aspects of laparoscopy in obese women. Currently the biggest controversy is the use of laparoscopy in malignant ovarian tumors. Our oncogynaecological study group at FN Motol prefers the laparotomic approach and we chose to include the set of advanced...

The main objectives of this master thesis are to evaluate and compare chosen classification algorithm for the tree species classification. With usage of satellite imagery Sentinel-2 and Landsat 8 is examined whether the better spatial resolution affects the quality of the resulted classification. According to past case studies and literature was chosen supervised algorithms Support Vector Machine, Neural Network and Maximum Likelihood. To achieve the best possible results of classification is necessary to find a suitable choice of parameters and rules. Based on literate was applied different settings which were subsequently evaluated by cross validation. All results are accompanied by tables, charts and maps which comprehensively and clearly summarize the answers to the main objectives of the thesis.

Meerkat (Suricata suricatta) is a mongoose species from South Africa. Insects are the primary food sources of their diet. Meerkat lives in groups of 2?30 individuals with a developed social structure. The group consists of a dominant pair and a different number of helpers of both sexes, which are involved in various forms of cooperation, for example care for cubs, guard service and maintaince of burrow. Meerkats are at risk of predation by mammalian predators, avian predators and snakes. One meerkat always seems to be a sentry and stands guard to keep the gang safe. When the guard senses danger they give a warning bark and the other members run for cover into their burrow. This study was done from June to September 2011 in zoo in Jihlava on a group of meerkats, which consisted of 13 individuals. There was used the method of direct observation by a scanning behaviour (behaviour sampling). Observation was specialized on sentinel behaviour. The main aim of this work was evaluate the results of observation and then compare this results with behaviour in the wild. By monitoring was demonstrably found, that dominant individuals contributed to guarding more frequently and the longest time and the juveniles contributed at least. There wasn´t set order in guarding. The most often was individually guarding or guarding in a group of 2 or 3 individuals.

Submitted by Caroline Piffer de Andrade (carol_piffer@hotmail.com) on 2018-04-28T18:02:37Z No. of bitstreams: 1 CarolinePifferdeAndrade.pdf: 3287357 bytes, checksum: beca78c3926ad0af4d896e61b2ecaf99 (MD5) / Approved for entry into archive by ALESSANDRA KUBA OSHIRO ASSUNÇÃO (alessandra@fct.unesp.br) on 2018-05-02T13:23:34Z (GMT) No. of bitstreams: 1 andrade_cp_me_prud.pdf: 3003528 bytes, checksum: 19259069721e1c717d15aa96a145d1fb (MD5) / Made available in DSpace on 2018-05-02T13:23:35Z (GMT). No. of bitstreams: 1 andrade_cp_me_prud.pdf: 3003528 bytes, checksum: 19259069721e1c717d15aa96a145d1fb (MD5) Previous issue date: 2018-03-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente estudo objetivou estimar as concentrações de clorofila-a (Chl-a) no reservatório da usina hidroelétrica de Ibitinga (RHI), localizado no Rio Tietê, estado de São Paulo, Brasil, por meio de coeficientes de absorção obtidos via algoritmos quase-analíticos (QAAs). Para isso, realizou-se uma caracterização bio-ótica e biogeoquímica do RHI, por meio de dados espectrais e de qualidade da água coletados em dois trabalhos de campo, conduzidos em Julho de 2016 e Junho de 2017. Os desempenhos das versões originais QAAV5 e QAAV6 em estimar as propriedades óticas inerentes (POIs) no RHI foram avaliados. Versões re-parametrizadas para dois reservatórios localizados no sistema em cascata do Rio Tietê, QAABBHR e QAAOMW, foram também testadas para a área de estudo. Além disso, foram avaliadas as performances de esquemas compostos pelas versões do QAA já mencionadas, seguidas por quatro modelos para estimativa de Chl-a, os quais utilizam coeficientes de absorção como dados de entrada. A distribuição espacial das concentrações de Chl-a foi analisada por meio da aplicação desses esquemas em uma imagem do sensor Ocean and Land Colour Instrument (OLCI) instalado a bordo do satélite Sentinel-3A, com aquisição coincidente com o segundo trabalho de campo realizado na área de estudo. A caracterização bio-ótica demonstrou variabilidade espacial e temporal dos constituintes oticamente significativos (COSs) no RHI, com predominância da absorção pelo material orgânico colorido dissolvido (CDOM). As versões do QAA testadas para o primeiro conjunto de dados não se mostraram completamente adequadas na obtenção de coeficientes de absorção em todos os comprimentos de onda. Com relação aos esquemas para estimativa de concentração de Chl-a, apenas aqueles baseados no QAAV5 foram capazes de obter resultados razoáveis - Raiz do Erro Médio Quadrático Normalizado (REMQN) < 47.50 % - para os dados da imagem OLCI. Todos os quatro modelos para estimativa de Chl-a testados apresentaram resultados similares para os dados de saída do QAAV5. Esses resultados enfatizam o desafio gerado pela grande variabilidade ótica dos sistemas em cascata, com relação à modelagem bio-óptica. Os resultados obtidos dão suporte a futuros trabalhos, os quais podem resultar em aplicações como o monitoramento do estado trófico na área de estudo a partir de dados de satélite, com maior acurácia proveniente do uso de modelos que possam estimar consistentemente suas POIs. / This research was aimed at retrieving chlorophyll-a (Chl-a) concentrations in Ibitinga Hydroelectric Reservoir (IHR), located at Tietê River, São Paulo State, Brazil, using absorption coefficients obtained via Quasi-analytical algorithms (QAAs). For this purpose, a bio-optical and bio-geochemical characterization of IHR was carried out, through spectral and water quality data collected in two field campaigns conducted in July, 2016 and June, 2017. The suitability of two QAA native forms (QAAV5 and QAAV6) in retrieving inherent optical properties (IOPs) in IHR was assessed. Versions re-parameterized for two reservoirs also located in the Tietê River cascading system, QAABBHR and QAAOMW, were also tested for the study area. Besides that, the performances of schemes composed by the QAA versions already mentioned followed by four models that use absorption coefficients as inputs for estimating Chl-a concentration in Ibitinga Reservoir were evaluated. Spatial distribution of Chl-a in the reservoir was analyzed, since these schemes were applied in an image of the Ocean and Land Colour Instrument (OLCI) sensor onboard Sentinel-3A satellite, with acquisition date coincident with the second field campaign. The bio-optical characterization showed spatial and temporal variability of optically significant constituent (OSC) in IHR and colored dissolved organic matter (CDOM) predominance in its absorption budget. None of the QAA versions tested for the first dataset was completely satisfactory in retrieving absorption coefficients for IHR in all wavelengths. Regarding the schemes for Chl-a concentration estimates, only the ones based on QAAV5 were able to obtain reasonable results - Normalized Root Mean Square Error (nRMSE) < 47.50 % - for the OLCI image data. All four models for Chl-a estimation tested presented similar results for QAAV5 outputs. These results highlight the challenge of copying with high optical variability in cascading systems. The results obtained support further works, which can, prospectively, lead to many practical applications, as monitoring of trophic state in the study area from satellite data, with higher accuracy provided by the use of models that can consistently retrieve the IOPs for this specific water system. / FAPESP: 2012/19821-1 e 2015/21586-9