Orientador: Regina Maura Bueno Franco / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-11T18:48:07Z (GMT). No. of bitstreams: 1 Leal_DiegoAveraldoGuiguet_M.pdf: 3198919 bytes, checksum: 4b596c748379fae87029d533ef64688a (MD5) Previous issue date: 2008 / Resumo: Moluscos bivalves por serem eficazes organismos filtradores acumulam e concentram substâncias, partículas e até mesmo patógenos em seus tecidos, se os locais onde vivem ou são cultivados receberem cargas de efluentes contaminados. Estes animais atuam como bioindicadores de contaminação fecal e, ao serem ingeridos crus ou mal cozidos, podem transmitir os patógenos acumulados em seus tecidos. Diversos estudos em diferentes países reportaram a presença de protozoários patogênicos como Cryptosporidium e Giardia em moluscos bivalves destinados ao consumo humano, porém, no Brasil estes dados são inexistentes. Diante deste cenário, é interessante e relevante investigar a ocorrência destes protozoários neste tipo de alimento, consumidos em diversas regiões do país. Este estudo teve a finalidade de avaliar a contaminação natural por oocistos e cistos dos protozoários parasitos em moluscos bivalves localizados em um ambiente de estuário do litoral norte do Estado de São Paulo; detectar as formas parasitárias em água de rio e água do mar; verificar se existe correlação entre fatores climáticos, físico-químicos e microbiológicos e a ocorrência natural dos parasitos nestes ambientes aquáticos e verificar se existe correlação entre a qualidade das águas e a contaminação dos moluscos que vivem nesta região. Os exemplares de moluscos foram processados através da homogeneização de tecidos específicos e submetidos a centrífugo-concentração com éter-PBS e as amostras hídricas foram analisadas pela técnica de filtração em membranas. A visualização dos protozoários foi realizada através da reação de imunofluorescência direta e a confirmação da morfologia dos protozoários feita com a utilização de microscopia de contraste de fase e a incorporação de um corante vital (DAPI). Cistos de Giardia foram detectados em 8 das 12 amostras de água do rio e uma amostra continha oocistos de Cryptosporidium. Ambos os patógenos foram detectados na água do mar, onde Cryptosporidium esteve presente em 40,0 % e Giardia em 20,0 % do total amostrado. O pool de homogenados teciduais de brânquias foi positivo para oocistos e cistos em dois períodos, com concentrações de 12/oocistos/animal e 50 cistos/animal. Não houve associação significativa entre os fatores climáticos, físico-químicos e microbiológicos e o número de oocistos detectados na água do rio e na água do mar; para os cistos, foi encontrada uma correlação significativa com coliformes termotolerantes (p = 0,007) na água do mar. Ademais, não foi possível estabelecer correlação entre a qualidade da água e o número de cistos e oocistos detectados nos tecidos das ostras. Esta é a primeira vez que oocistos de Cryptosporidium e cistos de Giardia foram encontrados em ostras de uma região costeira do país e também na América Latina. Estes achados têm importância para a saúde pública, pois refletem a extensão da contaminação dos ambientes e dos alimentos de origem marinha, requerendo a padronização de um controle de qualidade. Palavras-chave: Cryptosporidium spp.; Giardia spp.; moluscos bivalves; Crassostrea rhizophorae; água do mar; água de rio; estuário; esgoto / Abstract: Bivalve molluscs are great filter feeders that may accumulate and concentrate substances, particles and even pathogens in their tissues, if the places that they inhabit or are cultivated receive contaminated effluents dispose. These animals, which serve as biological indicators of faecal contamination, may transmit the protozoa accumulated in their tissues, whenever they are ingested in a raw or lightly cooked form. Several studies in different countries reported the presence of parasite protozoa like Cryptosporidium and Giardia in bivalve molluscs destined for human consumption, however, in Brazil, these data are non-existent. For this reason, it is interesting and relevant the investigation of the occurrence of these protozoan in this type of food, consumed in different regions of the country. The aim of this study was to evaluate the natural contamination of oocysts and cysts of parasite protozoan in bivalve molluscs located in an estuarine environment in the Northern coast of São Paulo State; detect this protozoan in river and seawater; verify if there is a correlation between climatic, microbiological, physical and chemical factors with the natural occurrence of parasites in aquatic environments and verify if there is a correlation between water quality and the contamination of bivalve molluscs present at the region. Bivalve molluscs were processed through the homogenization of specific tissues and submitted to centrifugal concentration with ether-PBS, and water samples were analyzed by membrane filtration technique. Protozoa were visualized with direct immunofluorescence antibody test and to confirm the morphology of the parasites, contrast-phase microscopy and the incorporation of a vital dye (DAPI) were used. Giardia cysts were detected in 8 of 12 samples of river water and one sample contained Cryptosporidium oocysts. Both pathogens were detected in marine water where Cryptosporidium were present in 40,0% and Giardia in 20,0% of all samples analyzed. Gill pools homogenates of oysters were positive for oocysts and cysts in two periods with a mean concentration of 12 oocysts/oyster and 50 cysts/oyster. There was no significant association between the climatic, physical, chemical and microbiological factors with the number of oocysts detected in river water and in seawater; for cysts, it was found a high association only with thermotolerant coliforms (p = 0,007) in seawater. Moreover, it was not possible to establish correlation between water quality and the number of oocysts and cysts detected in oysters tissues. This is the first time that Cryptosporidium oocysts and Giardia cysts were found in oysters from the coastal region of Brazil, and it is also the first report in Latin America to date. These findings might be of public health importance, reflecting the extension of the contamination in marine environment and on seafood, requiring a need for quality control standards. Key-words: Cryptosporidium spp.; Giardia spp.; bivalve molluscs; Crassostrea rhizophorae; seawater; river water; estuary; sewage / Mestrado / Parasitologia / Mestre em Parasitologia

A comprehensive survey of the presence of trihalomethane (THM) compounds, as chlorination by-products, in drinking water in Kuwait have been performed. The survey covers the whole drinking water treatment cycle, starting with sea water and ending with the consumer tap. The data generated by the survey was all derived from actual water treatment plants, operating under normal conditions. All four trihalomethane compounds, namely; chloroform (CHCI3), bromodichloromethane (CHBrCI2), dibromochloromethane (CHBr2CI) and bromoform (CHBr3) were covered. The study clearly showed that, although considerable amounts of THM compounds did form as a result of chlorination of sea water entering the multi-stage flash (MSF) distillation plants, these plants were highly efficient in removing these compounds. The average removal efficiency, based on THM compounds mass load in the sea water feed, was around 95%. Factors which were found to have an influence on the degree of formation of these compounds, include, chlorination practice (continuous vs. shock), sea water temperature, level of organic precursors and contact time. Of much more important consequence, as far as the presence of these compounds in drinking water is concerned, was the degree of THM compounds formation as a result of the chlorination of drinking water before it is pumped to the consumer. Here, not only all the compounds formed remain in the water but there is a definite tendency for continuous formation well after the actual chlorination process has taken place. Factors which were found affecting this formation include water temperature, contact time and chlorination dosage. Although, all samples collected showed that the presence of THM compounds was always below the United States Environmental Protection Agency maximum contaminant level of 100 ~g/L, a need exists for the optimization of all chlorination processes with particular emphasis on the chlorination of drinking water. In almost all kinds of water encountered in this study, bromoform was found to be by far the most dominant compound.

Orientador: Osvair Vidal Trevisan / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-29T00:01:03Z (GMT). No. of bitstreams: 1 RuidiazMunoz_Eddy_D.pdf: 4515503 bytes, checksum: 70497e20d04fea10c0814c3960b218d9 (MD5) Previous issue date: 2015 / Resumo: Em caracterização de reservatórios, é importante estudar e entender propriedades chaves na produção de petróleo. Em reservatórios carbonáticos, uma destas propriedades é a molhabilidade. Diretamente relacionada à interação rocha/fluido no reservatório, pode variar entre molhabilidade intermediária e a preferencial ao óleo. O objetivo principal deste trabalho foi o de estudar o mecanismo de alteração da molhabilidade em rochas de coquinas e dolomita de afloramentos. Foram realizados experimentos usando água com concentração de 35kppm e 200kppm de cloreto de sódio, água do mar modificada na composição iônica e água enriquecida com CO2. Inicialmente foram caracterizadas as rochas na sua estrutura e composição mineral seguido de um teste de forças capilares e molhabilidade inicial. Em seguida, foi investigada a adsorção/dissolução de ións de sulfato. Com o propósito de obter rochas com molhabilidade ao óleo, foi realizado um estudo de envelhecimento baseado no tempo de contato utilizando óleo morto e uma mistura constituída por óleo mineral e ácido naftênico (2%) sobre uma condição de saturação de 100%. A partir destes resultados foram preparadas rochas com saturação de água irredutível para medir a molhabilidade através de embebição espontânea e do índice de Amott_Harvey. As águas utilizadas foram salmouras em diferentes concentrações salinas, salmoura carbonatadas e água do mar modificada. Para encerrar o estudo, foram realizadas trocas de concentração salina e iônica, para observar os efeitos na recuperação e associá-los com a alteração da molhabilidade. Os resultados obtidos no estudo do envelhecimento, as coquinas não apresentaram variações na recuperação durante os tempos utilizados. Já para as rochas de dolomita, conforme se aumentou o tempo de envelhecimento, a recuperação diminuiu consideravelmente, fenômeno diretamente associado à adsorção de componentes polares durante o envelhecimento. Além disso, as rochas de dolomita responderam positivamente às trocas de concentração salina. No caso do uso de água do mar modificada, os resultados mostram que para as rochas de dolomita apresentaram-se dois cenários no fenômeno de alteração da molhabilidade; o primeiro relacionado com a presença de sulfato na água do mar e/ou a remoção do cloreto de sódio, e o segundo com a injeção de água de baixa salinidade. Para as rochas de coquina o fator relevante para obter volumes adicionais por efeitos da alteração da molhabilidade foi o acréscimo de concentração de sulfato, com a remoção do cloreto de sódio da água utilizada ou o uso de água do mar com altas concentrações de sulfato. Finalmente o estudo do efeito do CO2 na alteração da molhabilidade mostrou que, tanto pela embebição espontânea quanto pelo índice Amott_Harvey, a molhabilidade não é alterada significativamente com o uso de água carbonatada / Abstract: In reservoir characterization, it is important to study and understand properties that are key in oil production. One of these properties in carbonate reservoirs is rock wettability. Directly related to the reservoir rock/fluid interaction, rock wettability can vary from intermediate to preferably oil-wetting. The main objective of this work was to study the mechanism of wettability alteration in limestone and dolomite outcrop rocks. Experiments were carried out using sodium chloride brines at 35kppm and 200kppm, seawater brines modified in its ionic composition and sodium chloride brines at 35kppm and 200kppm enriched with CO2. Initially, the rocks samples were characterized in their mineralogy and structure and initial wetting and capillary forces. In the sequence tests were performed with the samples to investigate adsorption/dissolution of sulfate ions. In order to attain oil-wetting conditions, an aging study using dead oil or a mixture composed by synthetic mineral oil and naphthenic acid (2%) was undertaken, focusing contact time. After these results, rocks were prepared at irreducible water saturation for measuring the wettability by spontaneous imbibition and Amott_Harvey wettability index. Injection water was: brines of different salinities, modified seawater and brines enriched with CO2. To close the study, salinity and ionic concentration were switched, in order to check for additional recoveries and associate them with wettability alteration. The results obtained from the aging, study show that limestone had no variations in oil recovery for the aging time evaluated. In the case of dolomites, there was increase on oil recovery as the aging time increased. The occurrence is attributed to the adsorption of polar components during the aging. In addition, additional recoveries were obtained for dolomites with the switch of brine concentration. For the modified seawater, the results showed that wettability alteration in dolomite presented two scenarios; the first is related to the presence of sulphate ions in seawater or with the removal of sodium chloride, and the second one, the injection of low salinity water. For the limestone, the relevant factor for wettability alteration was the increase of sulfate ions associated with removal of sodium chloride from seawater or the use of seawater spiked with high concentrations of sulfate. Finally, there was no significant change on rock wettability when carbonated water was used. Both spontaneous imbibition and Amott_Harvey indices show no relevant effect of CO2 regarding wettability alteration / Doutorado / Reservatórios e Gestão / Doutor em Ciências e Engenharia de Petróleo

Corrosion in pipelines and reservoir tanks in oil plants is a serious problem in the energy industries around the world because it causes a huge economic loss due to not only frequent replacements of the parts of pipelines and tanks but also potential damage of the entire fields of crude oil. Previous studies have revealed that corrosions are generated mainly by microbial activities and they are now called as Microbial Influenced Corrosion (MIC) or simply bio-corrosion. Bacterial species actually causing bio-corrosion is crucial for the suppression of the corrosion. To diagnose and give proper treatment to pipelines in industrial plants, it is essential to identify the bacterial species responsible for bio-corrosions. For attaining at this aim, I conducted an analysis of the microbial community at the corrosion sites in pipelines of oil plants, using the comparative metagenomic analysis along with bioinformatics and statistics. In this study, I collected and analyzed various bio-corrosion samples from four different oil fields. First, I collected samples from the seawater pipelines that are essential in the oil fields to maintain seawater injection system (field#1), and then I conducted the metagenomic analysis of these samples. The metagenomes obtained revealed that samples in both sites contain a wide range of bacterial taxa. However, the comparative analysis of the microbial community with statistics in the comparison between sites with corrosion and without corrosion revealed the presence of microorganisms whose abundances were significantly higher in sites with corrosion. Some of these microbes can be sulfate reducers and sulfur oxidizers of which are considered to be casual agents in recent bio-corrosion models. In addition to the seawater pipelines, I also collect samples from corrosion sites in oil pipelines at Field #2 and #3. My metagenomic analysis combined with statistics showed that several microorganisms are speculated to be very active at the corrosion sites in the oil pipeline. Although biological mechanisms of forming bio-corrosion in the oil pipelines still remain unclear, these microbial species are suggested to be some of the responsible bacteria for bio-corrosion in the oil pipelines. Besides seawater injection systems, groundwater injection systems are often used, especially in inland oil fields. Therefore, more detailed understanding of biocorrosion in the groundwater injection system is also required in oil industries. In the present studies, I then analyzed the microbial communities in pipelines in the oil field where groundwater is used as injection water (field #4). I collected samples from four different facilities in the field #4. Metagenome analysis revealed that microbial community structures were largely different even among samples from the same facility. Treatments such as biocide and demineralization at each location in the pipeline may affect the microbial communities independently. The results indicated that microbial inspection throughout the pipeline network is important to protect industrial plants from bio-corrosions. Identifying the bacterial species responsible to bio-corrosion, this study provides us with information on bacterial indicators that will be available to classify and diagnose bio-corrosions. Furthermore, these species may be available as biomarkers to detect the events of bio-corrosion at an early stage. Then, any appropriate care such as the appropriate choice of biocides can be taken immediately and appropriately. Thus, my study will provide a platform for obtaining microbial information related to bio-corrosion that enables us to obtain a practical approach to protect them from bio-corrosion.

Content: Leather and leather products are known for its durability and luxuries which makes it more unique among the other synthetic materials. Breathability and visco-elastic properties make leather unique choice of biomaterial. Utilization of leathers in marine based applications is limited owing to reactivity of leather towards salt and weather conditions. Moreover, the choice of raw materials and chemicals used during leather manufacture has greatly influence the properties of the leather. An attempt has been made to understand the influence of sea conditions on leathers. Conventional chrome tanned and vegetable tanned leathers were incubated in sea water and subsequently processed into post tanning to evaluate the physical properties. To understand, the leaching of chemicals, dyed leathers are incubated at different humidity and saline conditions. Interestingly, chrome tanned leathers found to be friendlier to marine conditions whereas, vegetable tanned leathers lead to leaching of chemicals. Furthermore, leaching of chromium is negligible, and crust leathers resulted in soft leathers. Prolonged exposure of chrome tanned leathers under salt stress leads to more softness. This might be due to saline stress to the skin matrix. Moreover, the computability of conventional leather chemicals were also tested using sea water. The research provides a new insight on fine tuning the chemicals to suit marine based applications. Take-Away: A new insight on fine tuning the chemicals to suit marine based applications.

<p>I did my presentation through Centra infron of Professor Bjorn Palm and Dr. Sad Jarall.</p>

Le bore est nécessaire pour le développement des plantes supérieures (structuration de la paroi végétale). Il pose cependant des problèmes (défoliation, pourriture et chute des fruits mûrs). Pour l’homme, sa toxicité se traduit par des nausées, des diarrhées, des troubles du développement intellectuel, neurologique et physique. La pénurie en eau douce conduit à dessaler l’eau de mer pour augmenter la quantité en eau destinée à la consommation humaine, l’industrie et l’agriculture. Lors de ce procédé, il faut éliminer les ions majeurs mais aussi le bore présent à des concentrations élevées (> 4,5 mg L–1, environ 0,45 mM). Son usage dans l’industrie et son rejet dans l’environnement conduisent à la pollution des eaux souterraines et de surface. Son élimination est donc indispensable, sachant que l’Organisation Mondiale de la Santé recommande une valeur guide de 0,5 mg L–1 dans l’eau potable et une valeur maximale de 0,3 mg L–1 dans l’eau utilisée pour l’irrigation. Cette thèse porte sur l’étude cinétique et thermodynamique des échanges du bore à la surface de différents matériaux en fonction de paramètres physico-chimiques (pH, concentration initiale …) à l’aide d’essais en réacteurs fermés et en colonnes. Deux types de résines commerciales ont été choisies : (i) les résines échangeuses d’anions Ambersep 900-OH et Amberlite IRA 402 Cl avec des fonctions ammonium, (ii) les résines spécifiques Amberlite IRA 743 et Diaion CRB 03 ayant des fonctions méthylglucamine. Les premières essais en réacteurs fermés montrent que les échanges liquide-solide sont rapides avec une élimination du bore > 96 % pour t < 30 min pour Amberlite IRA 743, Diaion CRB 03 et Ambersep 900-OH. Pour t > 2 h, un équilibre est observé pour toutes les résines. Le modèle du pseudosecond ordre permet de décrire la cinétique de sorption pour les 4 résines. A l’équilibre, l’adsorption est maximum d’une part dans une gamme de pH compris entre 6 et 12 pour les 2 résines sélectives Amb IRA 743 et CRB 03, et d’autre part pour un pH de 8 pour la résine Ambersep 900-OH et un pH 10 pour la résine Amberlite IRA 402 Cl. A pH 8 et pour les concentrations en bore < 20 mM, la sorption du bore est représentée par le modèle de type Langmuir pour Amberlite IRA 743, Ambersep 900-OH et Diaion CRB 03. Par contre, la rétention du bore sur Amberlite IRA 402 Cl suit une isotherme de type linéaire. A pH 8 et pour des concentrations en bore < 20 mM, les capacités de sorption sont : 1, 0,7, 0,3 et 0,05 mmol g–1 pour Diaion CRB 03, Amberlite IRA 743, Ambersep 900-OH et Amberlite IRA 402 Cl, respectivement. Les résines Ambersep 900-OH, échangeuse d’anions, et Amberlite IRA 743, sélective, ont été utilisées pour les essais en colonnes en fonction de la concentration en bore et du temps de séjour. Pour la résine spécifique, le temps de séjour dans la colonne affecte fortement le comportement du bore : lorsqu’il diminue, son élution est rapide suivie d’une longue traînée ; lorsqu’il augmente, la courbe de percée correspond à un système à l’équilibre. Pour un temps de séjour élevé, les résultats confirment la non-linéarité observée lors des essais en réacteurs fermés. Pour la résine échangeuse d’anions, la non-linéarité est aussi confirmée. Ces essais permettent de différencier le comportement du bore lors de sa désorption. La régénération est obtenue après des traitements acides et basiques pour la résine spécifique alors qu’un traitement alcalin est suffisant pour la résine anionique. Une étude plus détaillée des mécanismes est en cours et permettra de les intégrer dans un même modèle. La fixation du bore sur des pectines et sa rétention par des membranes d’ultrafiltration (membranes de seuil de coupure différent) a aussi été étudiée. Les pectines ont été caractérisées (composition en sucre et en bore présent initialement) et la viscosité des solutions pectiques mesurée. Des essais de filtration ont permis de déterminer l’efficacité de production et de rétention du bore sur ces matériaux. / Boron is an element, which is necessary as essential nutrient for living organisms, especially for plants where it is involved in cell wall composition. But boron excess can cause some problems on the development of plants (defoliation, decay and fall unripe fruits), of humans and animals such as nausea, diarrhoea, dermatitis, lethargy. Boron toxicity also changes blood composition, caused disorder in neurological, physical, intellectual development. Nowadays, due to the shortage of fresh water sources, seawater desalination has been becoming an alternative fresh water supply. However, the presence of boron in seawater is quite high (4.5 mg L–1, around 4.5 mM). Moreover, the increasing use of boron in industries and its discharge to the environment has led to the contamination of surface and ground waters. As the result, boron removal, in production of drinking water becomes very important. Therefore, the World health organization has recommended a guideline of 0.5 mg L–1 B in drinking water and a maximum limit of 0.3 mg L–1 B in fresh water used for irrigation. The objective of this thesis is to study the mechanisms of boron surface exchange on different materials versus time and at equilibrium depending on some physicochemical parameters such as pH, initial boron concentration, reaction time in order to find a new exchanger for boron removal. Boron removal was carried out by ion exchange process using 2 types of resins: Amberlite IRA 743, Diaion CRB 03 as boron selective resins with methylglucamine functions, and Ambersep 900-OH and Amberlite IRA 402 Cl as anionic exchange resins with ammonium functions. From batch studies, fast exchange between resin surface and liquid phase was observed with boron removal up to at least 96 % within 30 min for Amberlite IRA 743, Diaion CRB 03 and Ambersep 900- OH. The reaction between resin surface and boron solution reached equilibrium after 2 h for all the resins. The pseudo-second order kinetic model was used to well describe the sorption kinetic process of the resins. At equilibrium, the experimental results showed that the maximum adsorption was observed to be achieved at pH 8 for Ambersep 900- OH, pH 10 for Amberlite IRA 402 Cl and independent on pH range from 6 to 12 for the 2 boron selective resins Amberlite IRA 743 and Diaion CRB 03. At pH 8 and for boron concentrations < 20 mM, the Langmuir-type relationship was used to fit the experimental data for Amberlite IRA 743, Ambersep 900- OH and resin Diaion CRB 03. In the range of studied boron concentration, the boron sorption onto Amberlite IRA 402 Cl followed linear-type behaviour. At pH 8 and for boron concentrations < 20 mM, the sorption capacities are: 1, 0,7, 0,3 et 0,05 mmol g–1 for Diaion CRB 03, Amberlite IRA 743, Ambersep 900- OH and Amberlite IRA 402 Cl, respectively. Column experiments were performed with the anionic resin Ambersep 900-OH and the selective one Amberlite IRA 743 by studying both the influence of boron concentration and the residence time. For the selective resin, if the residence time decreases, the boron breakthrough is fast followed by a long tail. For larger residence time, local equilibrium seems to be assumed. Results are thus consistent with batch experimental data. For the anionic resin, the nonlinear behaviour is also confirmed. Moreover, column experiments showed a strong difference during desorption. To regenerate resins, acid and basic treatments are necessary for the selective resin although a basic solution is enough for the anionic resin. A more detailed study of mechanisms is in progress in order to build a exchange model for predicting boron fate. Finally, characterization of pectins was also performed. Its composition (sugar and boron content) and the viscosity of pectin solutions were quantified. Filtration experiments allowed testing the efficiency of such material to remove boron too

Using a combination of hydrographic data and the trajectories and profiles of isobaric floats, this dissertation evaluates the connections between remote regions in the North Atlantic. First, I establish that the production and advection of the North Atlantic Subtropical Mode Water (STMW) introduces spatial and temporal variability in the subsurface nutrient reservoir of the subtropical gyre. As the mode water is formed, its nutrients are depleted by biological utilization. When the depleted water mass is exported to the gyre, it injects a wedge of low-nutrient water into the upper layers of the ocean. Contrary to intuition, cold winters that promote deep convective mixing and vigorous mode water formation may diminish downstream primary productivity by altering the subsurface delivery of nutrients. Next, the source of elevated nutrient concentrations in the Gulf Stream is assessed. The historical hydrographic data suggest that imported water advected into the Gulf Stream via the tropics supplies an important source of nutrients to the Gulf Stream. Because the high nutrients are likely imported from the tropics, diapycnal mixing need not be invoked to explain the Gulf Stream's high nutrient concentrations, as had been previously hypothesized. Furthermore, nutrients do not increase along the length of the Stream, as would be expected with strong diapycnal mixing.Finally, profiling float data are used to investigate how the Labrador Sea Water enters the Deep Western Boundary Current, one of the primary pathways by which it exits the subpolar gyre. With the trajectories and profiles of an extensive array of P-ALACE floats I evaluate three processes for their role in the entry of Labrador Sea Water in the Deep Western Boundary Current (DWBC): 1) LSW is formed directly in the DWBC, 2) Eddies flux LSW laterally from the interior Labrador Sea to the DWBC, and 3) A horizontally divergent mean flow advects LSW from the interior to the DWBC. Each of the three processes has the potential to remove heat from the boundary current, and both the formation of LSW directly in the boundary current and the eddy heat flux are possible sources of interannual variability in the exported LSW product. / Dissertation

The aim of this study was to develop drug delivery system based on poly(lactic acid-co-glycolic acid) (PLGA) nanoparticles (NPs) to achieve personalized treatment of selected skin disorders, like photo-aging, psoriasis and atopic dermatitis. Dead Sea Water (DSW) and Retinyl Palmitate (RP) were used as active agents and they were loaded in PLGA NPs prepared either as spheres or capsules by o/w or w/o/w methods. MgCl2 and bovine serum albumin (BSA) served as model active compounds. The diameter of the NPs was found to be in the range of 280 - 550 nm. The entrapment efficiency (E.E.) was less than 1% for RP, DSW and MgCl2, and 41% for BSA. Loading of Cl- together with BSA doubled the E.E. value of Cl- . In situ release studies showed a burst in the first day and more than 85% of the chloride content was released within a week. When the macromolecule BSA was encapsulated, a much slower and triphasic release profile was observed which continued for up to 80 days. In vitro tests were performed using L929 fibroblast cells. Results of MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) test revealed that none of the NPs were cytotoxic. Additionally, all particles were hemocompatible with hemolytic activity &lt / 1.5%. L929 fibroblast and Saos 2 human osteosarcoma cells were used to study the uptake of NPs by the cells. Particles accumulate near the nucleus. The characterization and cell viability tests, and drug release behavior indicate the suitability of these NPs for further testing to develop a patient specific skin diseases treatment approach.

Derramamentos de petróleo e derivados, como querosene e diesel, em água do mar são motivos de preocupação mundial devido aos sérios efeitos causados ao meio ambiente marinho e costeiro. A taxa de biodegradação de hidrocarbonetos em água do mar é afetada por inúmeros parâmetros físico-químicos e biológicos, incluindo o número e a diversidade de micro-organismos endógenos, as condições para a atividade de degradação microbiana (presença de nutrientes, oxigênio favorável e condições de pH e temperatura), a quantidade, a qualidade e a biodisponibilidade dos contaminantes e características da água do mar. Neste trabalho, dois planejamentos fatoriais completos 24 foram realizados para analisar a influencia do pH (6; 10 e 14) e das concentrações de querosene e nutrientes (sulfato de amônio e fosfato monobásico de potássio) sobre degradação de querosene e produção de bioemulsificantes/biossurfactantes por Candida lipolytica UCP 0988 em água do mar. A água do mar usada nos ensaios foi coletada em praia próxima ao Porto de Suape, Pernambuco, Brasil. Os ensaios de biodegradação foram realizados à temperatura de 28C, em um agitador rotatório a 200rpm, durante 5 dias. A levedura C. lipolytica UCP 0988 foi capaz de utilizar querosene (10%, 20% ou 30% v/v) e crescer em água do mar, suplementada com sulfato de amônio e fosfato monobásico de potássio, produzindo biossurfactantes com altas atividades de emulsificação. A fitotoxicidade de amostras biodegradadas coletadas com 5 dias foi avaliada usando técnicas de germinação e crescimento radicular de feijões-macáçar (Vigna ungiculata (L.) WALP.) / Spills of oil and oil products, such as kerosene and diesel in seawater are cause for concern worldwide due to serious effects caused to the marine and coastal environment. The rate of biodegradation of hydrocarbons in sea water is affected by many physical, chemical and biological parameters, including the number and diversity of endogenous microorganism, the conditions for microbial degradation activity (presence of nutrients, oxygen and favorable conditions pH and temperature), the quantity, quality and bioavailability of contaminants and characteristics of sea water. In this work, two 24 full factorial designs were carried out to analyze the influence of pH (6, 10 and 14) and concentrations of kerosene and nutrients (ammonium sulfate and potassium phosphate monobasic) on degradation of kerosene and production bioemulsifiers/biosurfactants by Candida lipolytica UCP 0988 in seawater. The seawater used in the tests was collected near the beach in Suape Harbor, Pernambuco, Brazil. The biodegradation tests were performed at the temperature of 28 C, on a rotatory shaker at 200 rpm, for 5 days. The yeast C. lipolytica UCP 0988 was able to use kerosene (10%, 20% or 30% v / v) and grows in seawater, supplemented with ammonium sulfate and potassium phosphate monobasic, producing biosurfactants with high emulsification activity. The phytotoxicity of biodegradated samples collected with 5 days was evaluated using seed germination and root elongation techniques with Makassar beans (Vigna ungiculata (L.) Walp.).