Submitted by Alberto Vieira (martins_vieira@ibest.com.br) on 2018-02-07T23:47:36Z No. of bitstreams: 1 414898.pdf: 15577866 bytes, checksum: e5045b61e3ca6b66ac2055accdee7df5 (MD5) / Made available in DSpace on 2018-02-07T23:47:36Z (GMT). No. of bitstreams: 1 414898.pdf: 15577866 bytes, checksum: e5045b61e3ca6b66ac2055accdee7df5 (MD5) Previous issue date: 1999-02-23 / A partir da análise de uma população de Scinax ruber (Laurenti, 1768) do Município de Magé (Estado do Rio de Janeiro, Sudeste do Brasil) são descritas detalhadamente a morfologia externa e a osteologia dos adultos, a ultra-estrutura dos espermatozóides, a vocalização e a morfologia externa das larvas. Espécies dos grupos "ruber'' e "x-signatus" são analisadas para fins de comparação. Scinax ruber caracteriza-se por apresentar: (1) porte de pequeno para médio ( comprimento rostro-anal igual a 26,3 mm nos machos e 29 ,6 nas fêmeas); (2) faixa dorso lateral (bege, creme ou amarelada com bordas marrom-escuras) iniciando-se na margem posterior dos olhos e estendendo-se até um pouco antes da região inguinal; (3) áreas ocultas das pernas e região inguinal marrons, sem manchas ("spots") amarelas ou alaranjadas; ( 4) larvas com terceira fileira inferior de dentículos levemente projetada, marcadamente mais curta que a segunda, representando 53,6 % do comprimento dessa; (5) canto de anúncio com estrutura harmônica pouco modulada, sendo emitidas entre 8 e 26 notas curtas por canto, cada nota apresentando pelo menos sete harmônicos nítidos; ( 6) frequência fundamental do canto de anúncio igual a 500 Hz e frequência... / The adult external morphology, osteology, spermatozoa ultrastructure, and calls from a population of Scinax ruber (Laurenti, 1768) from Magé (Rio de Janeiro State, southeastern Brazil) are described. The external morphology of tadpoles is also described. Species from the Scinax ruber and Scinax x-signatus groups are compared with S. ruber. The latter species can be distinguished by the following features: ( 1) small to medium size (snout-ventlength 26.3 mm in males and 29.6 mm in females); (2) dorsolateral stripes (beige, cream or yellowish with dark-brown borders) beginning on posterior border of eyes and extending to shortly before inguinal region; (3) concealed limb surfaces and inguinal region brown, without yellow spots; ( 4) oral disc of tadpoles with third inferior row of teeth remarkably shorter than second row, its length corresponding to 53.6 % of latter; (5) advertisement call presenting harmonic structure weakly modulated, with 8 to 26 short notes per call, each note with at least seven harmonics; ( 6) fundamental frequency of advertisement call at 500 Hz and dominant frequency...

Monascus é um fungo ascomiceto tradicionalmente utilizado na China. Os povos orientais utilizam o produto de sua fermentação em arroz não aglutinado, ao qual dão o nome de \"Ang-kak\", e no inglês, \"Red yeast rice\". Sabe-se que este extrato contém substâncias hipocolesterolêmicas, como a Monacolina K, inibidor competitivo da enzima HMG-CoA. Este trabalho se insere neste contexto uma vez que consiste na otimização da fermentação e secagem do extrato de Monascus ruber. Embora já existam estudos sobre a atividade biológica deste extrato, os quais comprovam seus benefícios, não há muitos estudos que visam otimizar a sua fermentação em meio submerso e a secagem do extrato. Para tanto, foram avaliados diversos parâmetros na fermentação através de dois planejamentos fatoriais. No primeiro planejamento, as variáveis estudadas foram o meio de cultura (meio arrozina-glicose e meio sólido de arroz) e agitação (0 rpm e 10 rpm). A agitação promoveu um leve aumento na produção de monacolina-K, já o meio líquido foi mais eficiente na produção desta substância do que o meio sólido de arroz. Baseado neste experimento escolheu-se o meio fermentativo para os demais estudos. No segundo experimento as variáveis estudadas foram a adição no meio arrozina-glicose de zinco, amônio e glutamato. Neste experimento pôde-se verificar que o a produção de monacolina K e de pigmentos foi maior no meio com concentrações intermediárias de zinco e de glutamato e com concentrações maiores de amônio. No estudo da secagem, realizou-se um planejamento Box Benkhin, a fim de se avaliar a influência da proporção do adjuvante: fármaco, do tempo de incorporação do excipiente e da temperatura sobre características do extrato seco como: densidade aparente, densidade de compactação, fator de Hausner, umidade residual, atividade de água, atividade antioxidante e teor de monacolina K. Em relação à proporção do adjuvante: droga pode-se afirmar que a menor produz pós com menor atividade de água e teor de umidade, porém todos os pós obtidos tiveram seu teor de umidade e atividade de água dentro do ideal e a análise estatística mostrou que a proporção do adjuvante: droga não influenciou de forma significativa a atividade de água e o teor de umidade; a proporção 7,5:1 produz melhor rendimento e pós com melhores propriedades de fluxo, por possuírem menores valores de índice de compressibilidade e fator de hausner, já com a proporção 10:1 fornece pós com maior teor de monacolina e maior atividade antioxidante. Em relação à temperatura pode-se afirmar que utilizando-se 50°C obteve-se pós com melhores propriedades de fluxo, ou seja, menor índice de compressibilidade e menor e fator de hausner. Utilizando temperatura de 80°C obteve-se menor atividade antioxidante, maior rendimento e maior teor de monacolina K. Contudo, a análise estatística mostrou que a temperatura não influenciou de forma significativa o teor de monacolina K. Com uma temperatura maior, 110°C obteve-se menor teor de umidade e maior teor de pigmentos vermelhos. Em relação ao tempo de mistura do adjuvante pode-se afirmar que com 1 minuto obteve-se maior teor de pigmentos e pós com melhores propriedades de fluxo, com 5 minutos obteve-se menor teor de pigmentos, maior rendimento, maior teor de monacolina K e menor atividade de água, já com 10 minutos obteve-se menor teor de umidade e maior porcentagem de inibição. A análise estatística demonstrou que o tempo de mistura não influencia de forma significativa a atividade antioxidante. / Monascus ruber is an ascomycete fungus traditionally used in China. Eastern peoples use the product of its fermentation in rice non-agglutinated, which they call Ang-kak (red yeast rice, in English). It is known that this extract contains hypocholesterolemic substances such as the Monacoline K, a competitive inhibitor of the HMG-CoA enzyme. This work comes into this context since it consists in the optimization of the fermentative and drying processes of the Monascus rubers extract. Despite the existence of studies on the biological activity of this extract, which support its benefits, not many aimed at optimizing the fermentative process in submerged conditions and the drying of the extract. This work aimed at optimizing the fermentative process and the drying of the Monascus rubers extract. In order to do such, several parameters of the fermentative process were evaluated through two factorial plannings. In the first one, the variables studied were the modes of culture (liquid culture and solid-state culture) and agitation (0 rpm and 10 rpm). Agitation led to a slight increase in the production of Monacoline-K, and the liquid culture was more efficient in the production of this substance than the solid-state culture. Based on these findings, the fermentative substrate for the following experiments was chosen. In the second experiment, the variables studied were the addition of zinc, ammonium and glutamate in the liquid culture. It was observed that the production of monacoline-k and pigments was increased in the substrates with intermediary concentrations of zinc and glutamate and higher concentration of ammonium. In the drying study, a Box-Benkhin planning was adopted in order to assess the influence of the adjuvant: drug proportion, excipient incorporation time and temperature over the characteristics of the dried extract, such as: apparent density, compactation density, Hausner factor, residual humidity, water activity, antioxidant activity and monacoline-K levels. Regarding the adjuvant: drug proportion, it can be stated that the 5:1 proportion produces powders with smaller water activity and humidity levels, however, all the powders obtained presented humidity levels and water activity within the ideal and, besides that, the statistical analysis showed that the adjuvant: drug proportion had no significant influence on water activity or humidity levels; the proportion of 7,5:1 produces greater quantities and powders with better flow properties, since they have lower values of IC and FH; and with the proportion of 10:1, powders with higher levels of monacoline-K and greater antioxidant activity can be obtained. Concerning temperature, it was observed that powders with better flow properties (lower IC and FH) were obtained at 50°C. At 80°C, lower antioxidant activity, greater quantities and higher levels of monacoline-K were observed, however, the statistical analysis showed that the temperature had no significant effect on the levels of monacoline-K. With a higher temperature (110°C), lower humidity levels and higher red pigment levels were obtained. Concerning the mix time adjuvant: drug proportion, it can be stated that with 1 minute higher levels of pigment and powders with better flow properties were obtained; lower levels of pigment, greater quantities, higher levels of monacoline-K and lower water activity were obtained with 5 minutes and; lower humidity level and greater percentage of inhibition were observed with 10 minutes, however, the statistical analysis showed that the mix time has no significant influence on the antioxidant activity.

Prinzipiell ist es möglich, dass sich Plattenepithelkarzinome aus klinisch gesund erscheinender Mundschleimhaut bilden. Allerdings konnte nachgewiesen werden, dass ein hoher Anteil aus bereits langfristig bestehenden Vorläuferläsionen, wie z.B. Leukoplakien und Läsionen, die dem Lichen planus zugeschrieben werden, hervorgeht. Der Expressionsnachweis verschiedener Tumormarker konnte bereits genutzt werden, um den Prozess der Karzinogenese besser zu verstehen und vielversprechende Methoden der Früherkennung zu entwickeln. Die vorliegende Arbeit beschäftigt sich mit der Analyse von immunzytochemisch gefärbten Bürstenbiopsien oraler Läsionen im Hinblick auf die Expression von GLUT1 und SHH und deren Bedeutung für den Prozess der malignen Transformation. Die untersuchte diagnostische Methode erreichte in der vorliegenden Arbeit eine Sensitivität von 80 % und eine Spezifität von 68 % für die Verwendung eines GLUT1-Antikörpers. Für SHH konnte eine Sensitivität von 60 % und eine Spezifität von 96 % ermittelt werden. / In principle, it is possible that squamous cell carcinomas form from seemingly clinically healthy oral mucosa. However, it has been shown that a large proportion results from long-term precursor lesions, such as leukoplakia and lesions attributed to lichen planus. The detection of various tumor markers has already been used to better understand the process of carcinogenesis and to develop promising methods of early detection. The present work deals with the analysis of immunocytochemically stained brush biopsies of oral lesions with regard to the expression of GLUT1 and SHH and their significance for the process of malignant transformation. In the investigated diagnostic method we achieve a sensitivity of 80% and a specificity of 68% for the use of a GLUT1 antibody. For SHH, a sensitivity of 60 % and a specificity of 96 % could be determined.

La dynamique de la thermocline Equatoriale Pacifique est en grande partie modulée par des phénomènes climatiques majeurs tels que l'ENSO ou la mousson indo asiatique. Nous utilisons des fossiles de deux morphotypes de l'espèce de foraminifères planctoniques Globigerinoides ruber comme traceurs de la stratification à la bordure Sud du Pacifique Ouest Equatorial, afin de retracer la dynamique climatique de cette région durant les derniers 800 000 ans. Nos résultats mettent en évidence un battement de la thermocline Pacifique en réponse aux variations Glaciaire /Interglaciaire, en relation avec les hautes latitudes. Lors des périodes glaciaires, la gyre subtropicale Sud renforcée permet le transport d'eaux froides venues de l'Antarctique vers le Pacifique Ouest. Ce mécanisme s'est progressivement intensifié depuis 800 000 ans en réponse à l'augmentation de l'amplitude de l'obliquité de l'orbite terrestre. L'étude morphologique des deux morphotypes de Globigerinoides ruber en réponse aux changements climatiques des derniers 800 000 ans, montre que la forme des tests est influencée par les changements environnementaux à l'échelle Glaciaire/Interglaciaire. Ces résultats suggèrent également que ces deux populations ont des exigences écologiques distinctes, permettant de les utiliser comme proxy de la stratification. La calibration mono-morphotypique pour les paléotempératures issues du Mg/Ca a également montré qu'il ne semble pas y avoir de différence de thermodépendance du Magnésium entre ces deux populations. / The Equatorial West Pacific thermocline dynamic is strongly modulated by climatic phenomenon as the ENSO and the Indo Asiatic monsoon. Here we use fossils of two morphotypes of the same planktonic foraminifera species, Globigerinoides ruber, from the Southern edge of the Western Equatorial Pacific as proxy of paleostratification, in order to track climate changes since the last 800 000 years. Our results show a regular beating of the Equatorial Pacific thermocline in response to Glacial/ Interglacial changes connected to the high latitudes. During glacials, the reinforced South subtropical gyre increases the advection of cold waters from the Antarctic to the West Pacific. This mechanism was progressively intensified by the increasing obliquity amplitude since 800 000 years. The morphometric study of the two morphotypes of Globigerinoides ruber indicates that the test shape responses to environmental changes at Glacial/Interglacial time scale. Furthermore these results suggest that those two populations have distinct environmental requirements, allowing to uses them as proxy of stratification. The mono-morphotypic calibration for Mg/Ca derived-paleotemperatures indicates that there is no specific thermodependance of magnesium between the two morphotypes.

Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / O objetivo do presente estudo foi investigar as concentrações de mercúrio total (HgT) nos músculos de Orthopristis ruber de quatro ecossitemas costeiros e identificar possíveis correlações existentes entre comprimento, peso, sexo, estação do ano e índices biológicos. O HgT foi analisado nas regiões de Cabo Frio (CF, n=31), Baía de Guanabara (BG, n=61), Baía de Sepetiba (BS, n=43) e Baía da Ilha Grande (BIG, n=32), as quais apresentam diferentes níveis de degradação ambiental. A BG recebe grande quantidade de efluentes domésticos e industriais de toda região metropolitana do Rio de Janeiro e tem sido considerada como uma das áreas mais poluídas do Brasil. Já na BS, a intensa atividade metalúrgica no seu entorno faz com que esta possa ser tida com nível de degradação intermadiária, enquanto CF e BIG são duas áreas vistas como áreas bem preservadas. As concentrações de HgT foram determinadas através de CV-AAS (FIMS - 400,Perkin Elmer) - utilizando boridreto de sódio como agente redutor. Foi utilizado DORM 3 (National Research Council, Canada) como material de referência (média da recuperação DP =99,2 4,9 %). As concentrações médias de HgT DP para BIG e CF foram, respectivamente, 209,8 118,9 ng/g, e 199,9 88,2 ng/g. Estas regiões apresentaram concentrações significativamente mais elevadas, enquanto a BG mostrou concentrações intermediárias (112,9 88,0 ng/g; ANCOVA, p<0,03). Por outro lado, a BS foi a região com as menores concentrações de HgT (11,3 11,5 ng/g). Tais resultados sugerem que, mesmo sendo áreas degradadas, o HgT não está totalmente biodisponível para BG e BS. Ademais, provavelmente as correntes oceânicas são uma fonte de mercúrio para CF e BIG, carreando mercúrio biodisponível para essas áreas. Para BG análises adicionais foram feitas a fim de identificar a acumulação de HgT ao longo do desenvolvimento ontogenético de O. ruber, uma vez que as concentrações do metal foram maiores em adultos do que em juvenis (PERMANOVA, p< 0,0001). As concentrações de HgT foram positivamente relacionadas tanto com o comprimento (Spearman test; r = 0,85; p <0,001) quanto com o peso (Spearman test; r =0,85; p <0,001) dos peixes da BG, mostrando que o O.ruber acumula HgT ao longo da vida. Diferenças entre sexos foram encontradas apenas para os O. ruber da BIG, onde fêmeas (300 ng/g) apresentaram maiores concentrações de HgT que os machos (~150 ng/g). Dentre os índices biológicos analisados, o índice gonadossomático foi o de maior relevância devido sua correlação negativa entre os níveis de HgT com todos os dados em conjunto (p<0.001), tanto para fêmeas (p<0.001) quanto para machos (p<0.02), sugerindo que o mercúrio pode afetar negativamente a reprodução de O.ruber. / The purpose of this study was to investigate total mercury (THg) concentrations in the muscle of Orthopristis ruber from four tropical coastal ecosystems and in the process identify if there is any correlation between the length, weight, sex, season and biological fish indexes. THg were evaluated among Cabo Frio (CF, n=31), Guanabara Bay (GB, n=61), Sepetiba Bay (SB, n=43) and Ilha Grande Bay (IGB, n=32); which presents different environmental degradation levels. Guanabara Bay receives contaminant input from hundreds of industrial and domestic sources in the Rio de Janeiro metropolitan area and has been regarded as one of the most degraded area in Brazil. Intensive metallurgical activity takes place around the edges of SB leading this area to be at an intermediate degree of contamination. Both CF and IGB are considered well preserved areas. THg concentrations were determined by CV-AAS (FIMS - 400,Perkin Elmer) with sodium borohydride as a reducing agent, using DORM-3 (National Research Council, Canada) as the standard reference material (mean recovery SD =99,2 4,9 %).The mean THg SD measured concentrations was 209,8 118,9 ng/g, and 199,9 88,2 ng/g for IGB and CF respectively. Those two areas showed significantly high THg levels, while GB presented intermediate THg concentrations (112,9 88,0 ng/g; ANCOVA, p<0,03). In contrast, Sepetiba Bay had the lowest levels of HgT (11,3 11,5 ng/g). These results suggests that THg is not as biologically available for BG and BS, even if both areas are considered graded, and probably has an oceanic current source that carries that metal up until CF and BIG. These results suggest that THg is not as biologically available for BG and BS, even if both areas are considered graded. Moreover, in CF and BIG, there is most likely an oceanic current that carries this metal up these areas. In GB, additional analyses were assessed in order to trace the THg accumulation trend through the ontogenetic growth of O. ruber, as THg levels were higher in adults than in juvenile fishes (PERMANOVA, p< 0,0001). to promote an ontogenetic profile for THg concentrations in O. ruber, concluding, THg levels were higher in adults than in juvenile fishes (PERMANOVA, p< 0,0001). THg concentrations had a positive relationship between the length (Spearman test; r = 0,85; p <0,001) and weight (Spearman test; r =0,85; p <0,001) of the fish from GB, showing that O. ruber accumulates THg during its lifespan. Differences between sexes were only found for O. ruber in IGB, where females (300 ng/g) showed a higher average of THg than males (~150 ng/g). Among the biologicals indexes, the gonadosomatic index was the most important as it showed a negative and significant relation between THg levels for all data together (p<0.001) as for both female (p<0.001) and male (p<0.02), suggesting THg may affect O.ruber reproduction

Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / O objetivo do presente estudo foi investigar as concentrações de mercúrio total (HgT) nos músculos de Orthopristis ruber de quatro ecossitemas costeiros e identificar possíveis correlações existentes entre comprimento, peso, sexo, estação do ano e índices biológicos. O HgT foi analisado nas regiões de Cabo Frio (CF, n=31), Baía de Guanabara (BG, n=61), Baía de Sepetiba (BS, n=43) e Baía da Ilha Grande (BIG, n=32), as quais apresentam diferentes níveis de degradação ambiental. A BG recebe grande quantidade de efluentes domésticos e industriais de toda região metropolitana do Rio de Janeiro e tem sido considerada como uma das áreas mais poluídas do Brasil. Já na BS, a intensa atividade metalúrgica no seu entorno faz com que esta possa ser tida com nível de degradação intermadiária, enquanto CF e BIG são duas áreas vistas como áreas bem preservadas. As concentrações de HgT foram determinadas através de CV-AAS (FIMS - 400,Perkin Elmer) - utilizando boridreto de sódio como agente redutor. Foi utilizado DORM 3 (National Research Council, Canada) como material de referência (média da recuperação DP =99,2 4,9 %). As concentrações médias de HgT DP para BIG e CF foram, respectivamente, 209,8 118,9 ng/g, e 199,9 88,2 ng/g. Estas regiões apresentaram concentrações significativamente mais elevadas, enquanto a BG mostrou concentrações intermediárias (112,9 88,0 ng/g; ANCOVA, p<0,03). Por outro lado, a BS foi a região com as menores concentrações de HgT (11,3 11,5 ng/g). Tais resultados sugerem que, mesmo sendo áreas degradadas, o HgT não está totalmente biodisponível para BG e BS. Ademais, provavelmente as correntes oceânicas são uma fonte de mercúrio para CF e BIG, carreando mercúrio biodisponível para essas áreas. Para BG análises adicionais foram feitas a fim de identificar a acumulação de HgT ao longo do desenvolvimento ontogenético de O. ruber, uma vez que as concentrações do metal foram maiores em adultos do que em juvenis (PERMANOVA, p< 0,0001). As concentrações de HgT foram positivamente relacionadas tanto com o comprimento (Spearman test; r = 0,85; p <0,001) quanto com o peso (Spearman test; r =0,85; p <0,001) dos peixes da BG, mostrando que o O.ruber acumula HgT ao longo da vida. Diferenças entre sexos foram encontradas apenas para os O. ruber da BIG, onde fêmeas (300 ng/g) apresentaram maiores concentrações de HgT que os machos (~150 ng/g). Dentre os índices biológicos analisados, o índice gonadossomático foi o de maior relevância devido sua correlação negativa entre os níveis de HgT com todos os dados em conjunto (p<0.001), tanto para fêmeas (p<0.001) quanto para machos (p<0.02), sugerindo que o mercúrio pode afetar negativamente a reprodução de O.ruber. / The purpose of this study was to investigate total mercury (THg) concentrations in the muscle of Orthopristis ruber from four tropical coastal ecosystems and in the process identify if there is any correlation between the length, weight, sex, season and biological fish indexes. THg were evaluated among Cabo Frio (CF, n=31), Guanabara Bay (GB, n=61), Sepetiba Bay (SB, n=43) and Ilha Grande Bay (IGB, n=32); which presents different environmental degradation levels. Guanabara Bay receives contaminant input from hundreds of industrial and domestic sources in the Rio de Janeiro metropolitan area and has been regarded as one of the most degraded area in Brazil. Intensive metallurgical activity takes place around the edges of SB leading this area to be at an intermediate degree of contamination. Both CF and IGB are considered well preserved areas. THg concentrations were determined by CV-AAS (FIMS - 400,Perkin Elmer) with sodium borohydride as a reducing agent, using DORM-3 (National Research Council, Canada) as the standard reference material (mean recovery SD =99,2 4,9 %).The mean THg SD measured concentrations was 209,8 118,9 ng/g, and 199,9 88,2 ng/g for IGB and CF respectively. Those two areas showed significantly high THg levels, while GB presented intermediate THg concentrations (112,9 88,0 ng/g; ANCOVA, p<0,03). In contrast, Sepetiba Bay had the lowest levels of HgT (11,3 11,5 ng/g). These results suggests that THg is not as biologically available for BG and BS, even if both areas are considered graded, and probably has an oceanic current source that carries that metal up until CF and BIG. These results suggest that THg is not as biologically available for BG and BS, even if both areas are considered graded. Moreover, in CF and BIG, there is most likely an oceanic current that carries this metal up these areas. In GB, additional analyses were assessed in order to trace the THg accumulation trend through the ontogenetic growth of O. ruber, as THg levels were higher in adults than in juvenile fishes (PERMANOVA, p< 0,0001). to promote an ontogenetic profile for THg concentrations in O. ruber, concluding, THg levels were higher in adults than in juvenile fishes (PERMANOVA, p< 0,0001). THg concentrations had a positive relationship between the length (Spearman test; r = 0,85; p <0,001) and weight (Spearman test; r =0,85; p <0,001) of the fish from GB, showing that O. ruber accumulates THg during its lifespan. Differences between sexes were only found for O. ruber in IGB, where females (300 ng/g) showed a higher average of THg than males (~150 ng/g). Among the biologicals indexes, the gonadosomatic index was the most important as it showed a negative and significant relation between THg levels for all data together (p<0.001) as for both female (p<0.001) and male (p<0.02), suggesting THg may affect O.ruber reproduction

[pt] Neste estudo, as propriedades bacterianas da estirpe Rhodococcus ruber in natura e ativada com NaOH 0,1M, foram analisadas. O estudo avaliou a influência dos cátions metálicos (Al3 positivo, Cr3 positivo, Fe3 positivo, Co2 positivo, Mg2 positivo e Ni2 positivo) sob o comportamento da estirpe bacteriana, no intervalo de concentração entre 10(-3) a 10(-6) mol/L. As amostras bacterianas foram caracterizadas por espectroscopia na faixa do infra-vermelho com transformada de Fourier (FTIR). O ponto isoelétrico (PIE) da estirpe R. Ruber foi obtido através das análises de potencial zeta. Os resultados demonstraram um PIE com pH igual 2,4 para a estirpe in natura, já quando ativada com NaOH 0,1M o PIE não foi evidenciado. A superfície bacteriana da estirpe ativada se apresentou levemente mais negativa do que a superfície da bactéria in natura. Para todas as amostras, observou-se alteração no potencial zeta durante a interação bacteriana com os íons estudados. Os resultados não apresentam diferenças significativas entre a bactéria in natura e ativada. As amostras permaneceram carregadas negativamente nos pH estudados, para todos os cátions, exceto Fe3 positivo. Por fim, diante dos resultados apresentados, acredita-se que a estirpe Rhodococcus ruber é uma opção viável para estudos voltados ao tratamento de efluentes contaminados por metais. / [en] In this study, the Rhodococcus ruber bacterial strain properties of in nature and activated with 0.1M NaOH were analyzed. The study evaluated the influence of metal ions (Al3 plus, Cr3 plus, Fe3 plus, Co2 plus, Mg2 plus and Ni2 plus) on the behavior of the bacterial strain in the concentration range from 10(-3) to 10(-6) mol/L. Bacterial samples were characterized by infra-red spectroscopy - Fourier transform Infra-red (FTIR). The isoelectric point (IEP) of the bacterium R. ruber was obtained by analysis of zeta potential. The results showed an IEP at pH equal 2.4 to strain in nature, in the other hand the IEP of activated strain (0.1M NaOH) was not observed. Bacterial surface-active strain showed slightly more negative than the surface of the bacterium in nature. All samples demonstrated changes in pH zeta potential during bacterial interaction with the analyzed ions. Samples remained negatively charged at the pH studied to all cations except Fe3 plus. Finally, it s believed that the bacterium Rhodococcus ruber is a viable option for the treatment of metal contaminated wastewater.

The objective of this project is to reconstruct a picture of initial Laurentide Ice Sheet retreat at the end of the Last Glacial Maximum (LGM) using geochemical proxies in Gulf of Mexico sediments, and place the reconstruction into global perspective. The project asks two questions. (1) Can a time frame be established for initial retreat of the Laurentide Ice Sheet? (2) If so, how does the timing compare to that of other large ice sheets and mountain glaciers in both hemispheres? Sediment core MD02-2550 from the anoxic Orca Basin offers excellent preservation and a high sediment accumulation rate. Twelve accelerator mass spectrometry 14C dates provide very good age control from 18.36 - 23.88 ka, the transitional period from glacial to deglacial conditions. Paired Mg/Ca and d18O from the planktonic foraminifera Globigerinoides ruber (pink variety) were combined with a matching record from the upper half of the same core from a previous study (Williams et al., 2010), expanding the record to 10.73 - 23.86 ka. Sea surface temperature (SST) derived from Mg/Ca exhibits a mean value of 23.0 ± 0.8°C through the LGM (18.4-23.9 ka), ~3.9°C below the modern summer mean. At 18.4 ka, mean values drop in an anomalous cold snap, exhibiting a mean of 21.7°C that lasted until 17.8 ka. At 17.8 ka, SST begins a recovery warming toward present day conditions. This warming occurs markedly early relative to the onset of the Bølling-Allerød warm period, known best from Greenland ice core records. The d18O of seawater exhibits no sustained shift toward more depleted values that would be consistent with a single major surge of initial meltwater. Instead, d18Osw appears to have been over 1.5 per mil below the modern mean throughout the LGM, persisting through the early deglacial period, and not shifting toward more positive values until well into the Younger Dryas. The corresponding salinity estimates were likewise ~2 psu lower than modern surface waters. Several negative excursions (~1 per mil) during the LGM and deglaciation coincide with millennial-scale retreats of individual lobes along the southern margin of the Laurentide Ice Sheet. These retreats and re-advances have previously been suggested to mirror small short-term excursions in Greenland ice core d18O, that reflects air temperature changes. The consistently depleted d18Osw-ivc values and corresponding salinity estimates through the LGM require a mechanism to create a steady-state lower salinity environment in the northern Gulf of Mexico during the LGM, which would persist as SST changed.

Studies of planktic foraminifers have been, and continue to be, very important to paleoceanographic reconstructions and are dependent on the integrity of the carbonate tests. This study investigates the methods and procedures that can be used to obtain an accurate planktic foraminifer assemblage. Samples from Orca Basin boxcore OB-BC4D were processed and examined to obtain census data on planktic foraminifers. Experimentation of the splitting technique demonstrates the method is acceptable for estimating a planktic foraminifer assemblage. The effects of a sonication step in the processing of the faunal assemblage were also examined and revealed that sonication is not recommended for processing planktic foraminifers for faunal-assemblage analyses. Census data revealed downcore variation in the foraminifer species and intervals of increased dissolution over the last 1000 years.

Abrupt, millennial-scale climate oscillations, known as Dansgaard-Oeschger (D-O) cycles, characterized the climate system during the last ice age. Proxy evidence suggests these climate oscillations resulted in global-scale reorganizations in the hydrological cycle. For this study, Mg/Ca-paleothermometry and stable isotope measurements were combined on the planktonic foraminifera Globigerinoides ruber (white variety) from Florida Straits sediment core KNR166-2 JPC26 (24*19.61'N, 83*15.14'W; 546 m depth) to reconstruct a high-resolution record of sea surface temperature and delta18OSW (a proxy for upper water column salinity) during Marine Isotope Stages 2 and 3 from 20-35.45 ka BP. As additional proxies for upper water column salinity change, Ba/Ca ratios in G. ruber were also measured to determine the relative contribution of local riverine input on the delta18OSW record and a faunal abundance count record of the planktonic foraminifera N. dutertrei abundance was developed. These results show that rapid upper water column salinity changes occurred across D-O events in the Florida Straits, coeval with climate change in the high-latitude North Atlantic. Furthermore, the G. ruber Ba/Ca record suggests that riverine-derived meltwater from the Gulf of Mexico did not significantly impact surface salinity in the Florida current, calling into question the role of Mississippi River discharge on Atlantic Meridional Overturning Circulation (AMOC) during MIS 2 and 3. Instead, the most likely cause of MIS 2 and 3 salinity changes in the Florida Straits were variations in the strength and position of the Intertropical Convergence Zone. Finally, the timing of surface salinity change was compared with the benthic delta18OC record from the same core. A recent study showed that benthic delta18OC changes on the Florida Margin can be combined with contemporaneous records from the Bahamas Margin to reconstruct Florida Current transport related to AMOC variability. These results show that atmospheric circulation changes lead AMOC changes on the transition out of cold stadial events, suggesting the trigger for these abrupt climate events may reside in the tropics rather than in the high-latitude North Atlantic as previously thought.