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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

The Reality of Fear: Preaching in a Frightened World

Roser, Traugott 28 November 2019 (has links)
Fear is a recurrent theme in today’s popular culture. Film director Steven Spielberg’s lifelong work presents the full range from awe and fear to terror, heading towards a deeply humanist approach of overcoming fear. This article puts homiletics into the context of current sociocultural discourse by applying the concept of ‘paradigm scenario’ (Ronald de Sousa) to fear in media culture and preaching. Preaching, like film, works with emotions such as fear and anxiety, initiating strong physical and mental reaction. To preach within a fearful world demands that one be aware of the psychology of fear. As much as preachers are ready to face their personal fears, they abstain from frightening others. At best, preaching is the art of supporting people to live life liberated by the gospel, speaking up against those who create an atmosphere of fear. The gospel provides numerous paradigm scenarios of courage and vision.
62

What happened last night in Sweden?: To preach without fear in a Scandinavian Folk Church, in a situation when populist nationalism rises in the context of migration.

Göranzon, Anders 06 December 2019 (has links)
This article focuses on the situation in the Church of Sweden, one of the largest Lutheran churches in the world. The links between the state and the church in Sweden were only recently cut. Political parties still engage with church policy and form the majority of the Church Assembly as well as many local Church councils. When nationalistic parties also are involved in church policy this becomes a challenge. Homiletics is taught at the Church of Sweden Institute for Pastoral Education as part of the final, ministerial year. At the Institute we make use of North American literature by authors like Brueggemann, Lose, Tubbs Tisdale and Troeger. There are many differences between the Scandinavian and the North American contexts. This paper seeks to investigate how homiletical training in one context is carried out with the use of textbooks from another, different context. How can homiletics based on North American theologies fit into a Folk Church context? How does a North American homiletic approach encourage Swedish students to preach a prophetic word of God, without fear, in a situation when populist nationalism rises in the context of migration? How can prophetic preaching, as described by for instance Brueggemann and Tisdale, be contextualised in this situation? This article discusses when and how prophetic preaching inspired from the Biblical example, with its narratives and with metaphors and poetic language, should be used and when a more confrontational, head-on witness is needed.
63

Preaching from Sanctuary

Madrazo, Tito, Ruiz, Alma 06 December 2019 (has links)
In the midst of the tense immigration debates taking place in the United States, the authors share insights from a number of sermons preached by first-generation Hispanic immigrants as part of a preaching peer-group. The preachers delivered these messages in a church that was providing protective sanctuary for an undocumented immigrant who was a member of the peer-group. The sermons were developed and delivered for an imaginary audience of either Hispanic immigrants or native-born Anglo-Americans and offer prophetic words of both comfort and judgment.
64

Estudo dos radionuclídeos naturais - Ra-226, Ra-228 e Pb-210 - em alguns registros sedimentares do Atlântico Sudoeste ao longo do Holoceno / Study of natural radionuclides - 226Ra, 228Ra and 210Pb - in marine sediment cores from Southwest Atlantic during the Holocene

Costa, Alice Miranda Ribeiro 19 August 2016 (has links)
Os radionuclídeos naturais das séries radioativas do 238U e do 232Th têm sido aplicados com sucesso como traçadores de processos ambientais atuais e mudanças climáticas. O 210Pb (meia-vida de 22,2 anos) é empregado na técnica de datação geocronológica de testemunhos sedimentares dos últimos 100-150 anos e na determinação de taxa de sedimentação. As concentrações dos isótopos 226Ra e 228Ra (meia-vida de 1.600 anos e 5,75 anos, respectivamente) auxiliam no cálculo das atividades de 210Pb em excesso no sedimento e auxiliam na identificação de processos marinhos importantes, como, por exemplo, a intrusão de água subterrânea. Neste trabalho foram quantificadas as concentrações de atividade de 226Ra, 228Ra e 210Pb em quatro testemunhos marinhos curtos coletados desde a plataforma continental até o talude superior do Atlântico Sudoeste. A partir dos resultados obtidos, as taxas de sedimentação em cada local e as idades de cada fatia de sedimento foram determinadas pelo método de datação geocronológica com 210Pb. As amostras sedimentares sofreram digestão total ácida em microondas. A separação radioquímica sequencial de 226Ra, 228Ra e 210Pb foi realizada com a obtenção dos precipitados de Ba(Ra)SO4 e PbCrO4. As medidas α total do 226Ra e β total do 228Ra e do 210Pb a partir dos precipitados foram feitas em um detector proporcional de fluxo gasoso de baixa radiação de fundo. Com relação aos testemunhos analisados, as concentrações de atividade dos radionuclídeos variaram de 14 Bq.kg-1 a 154 Bq.kg-1 para o 226Ra; de 17 Bq.kg-1 a 45 Bq.kg-1 para o 228Ra; de 20 Bq.kg-1 a 2.073 Bq.kg-1 para o 210Pb. Valores altos de 210Pb foram encontrados no topo de todos os perfis sedimentares, proveniente principalmente da deposição atmosférica. Os dados coletados neste trabalho estão na mesma faixa de grandeza de outros relacionados a medições de 226Ra, 228Ra, 210Pb em áreas não contaminadas do Oceano Atlântico Sudoeste. As taxas de sedimentação diminuíram com o aumento da profundidade de coluna dágua, cujos valores variaram de 0,049 cm.ano-1 a 0,40 cm.ano-1. / Natural radionuclides from 238U and 232Th series have been successfully applied as tracers of environmental process and climate changes. The 210Pb (half-life of 22.2 years) is used in the geochronological dating technique of sediment cores of the last 100-150 years, and its respective sedimentation rate determination. The study of 226Ra and 228Ra concentrations (half-lives of 1,600 years and 5.75 years, respectively) helps calculate the activity of 210Pb in excess in the environment, besides being important tracers of marine processes, as ground water discharge. In this work it was determined the activity concentrations of 226Ra, 228Ra and 210Pb in four short marine cores collected since the continental platform to upper slope of Southwest Atlantic Ocean. Taking into account the results obtained, sedimentation rates and the ages of each sediment layer were determined using the geochronological dating method with 210Pb. All sediment samples were total acid digested in microwave. The sequential radiochemical separation of 226Ra, 228Ra, 210Pb were performed, obtaining in the end the precipitation of Ba(Ra)SO4 and PbCrO4. The gross α measurements of 226Ra and gross β measurements of 228Ra and 210Pb from the precipitates were carried out in a gas-flow low background proportional counter. Concerning all cores analyzed, the activities concentrations of 226Ra ranged from 14 Bq.kg-1 to 154 Bq.kg-1; the concentrations of 228Ra ranged from 17 Bq.kg-1 to 45 Bq.kg-1; and the concentrations of 210Pb ranged from 20 Bq.kg-1 to 2,073 Bq.kg-1. High values of 210Pb were observed on the top of all the cores studied, mainly related to atmospheric deposition. The results obtained in this work were of the same order of magnitude of those reported in the literature available on non contaminated areas of Southeast Brazilian Coast. Sedimentation rates fall with the increase of water column depth and ranged from 0,049 cm.ano-1 to 0.40 cm.y-1.
65

Avaliação do potencial mutagênico de corantes têxteis por meio do ensaio de micronúcleo / Evaluation of the mutagenic potential of textile dyes using the micronucleus assay

Cesila, Cibele Aparecida 27 October 2015 (has links)
Os corantes possuem grande importância nos diversos segmentos industriais, sendo utilizados em medicamentos, cosméticos, alimentos, roupas, plásticos, borracha, dentre outros. Atualmente, são produzidos no mundo mais de 7 x 105 toneladas de corantes por ano, sendo que aproximadamente 26.500 toneladas/ano são consumidas no Brasil. A produção desses compostos, apesar de ter grande importância econômica é alvo da preocupação ambiental, pois cerca de 2 a 50% dos corantes utilizados na indústria alcançam o ambiente aquático durante o processo de produção e de processamento têxtil. Desta forma aproximadamente 280.000 toneladas de corantes da indústria têxtil são descarregados nos efluentes industriais a cada ano no mundo. Dentro desse contexto, os estudos envolvendo a avaliação de risco de corantes e seus produtos de degradação são de grande importância para a análise do impacto que esses compostos podem causar à saúde humana e ao ecossistema. O Acid Black 210 é um azo corante frequentemente utilizado no tingimento do couro, algodão e tecido de lã, representando aproximadamente 80 a 90% do corante de cor preta utilizado na indústria. O Disperse Red 73 é um azo corante de cor vermelha, frequentemente utilizado no tingimento de tecidos. No entanto, não existem estudos publicados na literatura científica sobre o potencial genotóxico e toxicológico desses corantes e sobre o monitoramento da presença desses corantes em águas superficiais. Estudos preliminares realizados em nosso laboratório, mostraram que o corante Disperse Red 73 induziu mutagenicidade nas linhagens TA98 e TA100 de Salmonella typhimurium e que foi extremamente tóxico para a espécie de Daphnia similis em ensaios de toxicidade aguda. Desse modo, esse trabalho teve como objetivo avaliar o potencial mutagênico dos corantes Acid Black 210 e Disperse Red 73 através do ensaio de micronúcleo em células HepG2 e avaliar os efeitos ecotoxicológicos agudos do corante Acid Black 210 utilizando os organismos da espécie Daphnia similis. Adicionalmente foram realizados os ensaios de avaliação de proliferação celular, ensaio de avaliação da morte celular por necrose e apoptose e ensaio de parada do ciclo celular utilizando o corante Acid Black 210 em células HepG2. Os resultados obtidos mostraram que o corante Disperse Red 73 não induziu danos cromossômicos em células HepG2 nas condições testadas. O Acid Black 210 não provocou a morte celular por apoptose e/ou necrose, em altas concentrações provocou parada no ciclo celular e induziu a citotoxicidade nos ensaios de proliferação celular. Os ensaios de micronúcleo realizados com o corante Acid Black 210 foram inconclusivos. Portando, os resultados obtidos nesse trabalho mostram que não ha indícios de que o corante Disperse Red 73 induza mutações cromossômicas e sugerem que o corante Acid Black 210 possua baixa toxicidade. No entanto, outros ensaios serão necessários, para que seja realizada uma avaliação de risco ambiental e para os seres humanos. Os resultados obtidos nesse trabalho juntamente com outros resultados do nosso grupo de pesquisa fornecerão subsídios para a realização da avaliação do perigo e caracterização do risco de exposição dos seres vivos a esses corantes. / Dyes and pigments are important compounds in different areas, for example in the medicine, cosmetic, food, clothing, plastic, rubber, and other industries. Currently, the production of these compounds is around 7 x 106 tons per year all over the world, with 26,500 tons per year being consumed in Brazil. The production of dyes, despite its economic relevance, is a subject of environmental concern, because 2 to 50 % of dyes are discharged directly into wastewater during their production process, corresponding to approximately 280,000 t of textile dyes being discharged in the environment worldwide through industrial effluents every year. In this context, the studies of the risk assessment of the dyes and their degradation products are very relevant to assess the impact of these compounds to the human health and the ecosystem. The Acid Black 210 is an azo dye commonly used in the dyeing of leather, cotton, and wool, representing approximately 80 to 90 % of the black dye used in the industry. However, there are not published studies in the scientific literature about the genotoxic potential and the toxicological concerns of this dye, including its monitoring presence in surface waters. Preliminary studies in our laboratory had shown that the Disperse Red 73 dye induces mutagenicity in the TA98 and TA100 Salmonella typhimurium strains and it is extremely toxic to Daphnia similis in acute toxicity tests. Thus, this study aimed to evaluate the mutagenic potential of the dyes Acid Black 210 and Disperse Red 73 through the micronucleus assay in HepG2 cell, and the acute ecotoxicological effects of the dye Acid Black 210 using the Daphnia similis test. Additionally, it was performed cell proliferation tests, the evaluation of the cell death by apoptosis and necrosis, and the cell cycle arrest assay using the Acid Black 210 dye in HepG2 cells. The results obtained in this study showed that the Disperse Red 73 dye did not induce chromosomal damage in HepG2 cells under the conditions tested. Acid Black 210 dye did not cause cell death by apoptosis and/or necrosis, at higher concentrations cause arrest cell cycle and induced cytotoxicity in cell proliferation assays. Micronucleus assays performed with the dye Acid Black 210 showed inconclusive. Therefore, the results of this study show that there is no evidence that the Disperse Red 73 dye induces chromosomal mutations and suggest that the Acid Black 210 dye has low toxicity. However, other tests will be required to do environmental and human risk assessments of these dyes. The results of this study along with other results of our research group will provide these additional requirements.
66

Estudo dos radionuclídeos naturais - Ra-226, Ra-228 e Pb-210 - em alguns registros sedimentares do Atlântico Sudoeste ao longo do Holoceno / Study of natural radionuclides - 226Ra, 228Ra and 210Pb - in marine sediment cores from Southwest Atlantic during the Holocene

Alice Miranda Ribeiro Costa 19 August 2016 (has links)
Os radionuclídeos naturais das séries radioativas do 238U e do 232Th têm sido aplicados com sucesso como traçadores de processos ambientais atuais e mudanças climáticas. O 210Pb (meia-vida de 22,2 anos) é empregado na técnica de datação geocronológica de testemunhos sedimentares dos últimos 100-150 anos e na determinação de taxa de sedimentação. As concentrações dos isótopos 226Ra e 228Ra (meia-vida de 1.600 anos e 5,75 anos, respectivamente) auxiliam no cálculo das atividades de 210Pb em excesso no sedimento e auxiliam na identificação de processos marinhos importantes, como, por exemplo, a intrusão de água subterrânea. Neste trabalho foram quantificadas as concentrações de atividade de 226Ra, 228Ra e 210Pb em quatro testemunhos marinhos curtos coletados desde a plataforma continental até o talude superior do Atlântico Sudoeste. A partir dos resultados obtidos, as taxas de sedimentação em cada local e as idades de cada fatia de sedimento foram determinadas pelo método de datação geocronológica com 210Pb. As amostras sedimentares sofreram digestão total ácida em microondas. A separação radioquímica sequencial de 226Ra, 228Ra e 210Pb foi realizada com a obtenção dos precipitados de Ba(Ra)SO4 e PbCrO4. As medidas α total do 226Ra e β total do 228Ra e do 210Pb a partir dos precipitados foram feitas em um detector proporcional de fluxo gasoso de baixa radiação de fundo. Com relação aos testemunhos analisados, as concentrações de atividade dos radionuclídeos variaram de 14 Bq.kg-1 a 154 Bq.kg-1 para o 226Ra; de 17 Bq.kg-1 a 45 Bq.kg-1 para o 228Ra; de 20 Bq.kg-1 a 2.073 Bq.kg-1 para o 210Pb. Valores altos de 210Pb foram encontrados no topo de todos os perfis sedimentares, proveniente principalmente da deposição atmosférica. Os dados coletados neste trabalho estão na mesma faixa de grandeza de outros relacionados a medições de 226Ra, 228Ra, 210Pb em áreas não contaminadas do Oceano Atlântico Sudoeste. As taxas de sedimentação diminuíram com o aumento da profundidade de coluna dágua, cujos valores variaram de 0,049 cm.ano-1 a 0,40 cm.ano-1. / Natural radionuclides from 238U and 232Th series have been successfully applied as tracers of environmental process and climate changes. The 210Pb (half-life of 22.2 years) is used in the geochronological dating technique of sediment cores of the last 100-150 years, and its respective sedimentation rate determination. The study of 226Ra and 228Ra concentrations (half-lives of 1,600 years and 5.75 years, respectively) helps calculate the activity of 210Pb in excess in the environment, besides being important tracers of marine processes, as ground water discharge. In this work it was determined the activity concentrations of 226Ra, 228Ra and 210Pb in four short marine cores collected since the continental platform to upper slope of Southwest Atlantic Ocean. Taking into account the results obtained, sedimentation rates and the ages of each sediment layer were determined using the geochronological dating method with 210Pb. All sediment samples were total acid digested in microwave. The sequential radiochemical separation of 226Ra, 228Ra, 210Pb were performed, obtaining in the end the precipitation of Ba(Ra)SO4 and PbCrO4. The gross α measurements of 226Ra and gross β measurements of 228Ra and 210Pb from the precipitates were carried out in a gas-flow low background proportional counter. Concerning all cores analyzed, the activities concentrations of 226Ra ranged from 14 Bq.kg-1 to 154 Bq.kg-1; the concentrations of 228Ra ranged from 17 Bq.kg-1 to 45 Bq.kg-1; and the concentrations of 210Pb ranged from 20 Bq.kg-1 to 2,073 Bq.kg-1. High values of 210Pb were observed on the top of all the cores studied, mainly related to atmospheric deposition. The results obtained in this work were of the same order of magnitude of those reported in the literature available on non contaminated areas of Southeast Brazilian Coast. Sedimentation rates fall with the increase of water column depth and ranged from 0,049 cm.ano-1 to 0.40 cm.y-1.
67

Radiation-induced fibrosis : Characterization of the anti-fibrotic mechanisms displayed by pentoxifylline/vitamin E / Fibrose radio-induite : Mécanismes moléculaires impliqués dans l’action anti-fibrosante exercée par l’association pentoxifylline-vitamine E

Hamama, Saad 21 November 2012 (has links)
La fibrose radio-induite est une complication sévère et tardive de la radiothérapie. Plusieurs études cliniques ont montré que la combinaison pentoxifylline-vitamine E est un traitement sûr et efficace contre la fibrose. Cependant, les mécanismes moléculaires de son efficacité restent inexplorés. Nous avons montré l’efficacité de la combinaison pentoxifylline-vitamine E dans l’entéropathie radique dans une faisabilité clinique. En parallèle, en utilisant un modèle unique, in vitro, de cellules musculaires lisses intestinales primaires isolées des personnes atteintes de l’entéropathie radique, nous avons montré une synergie entre la pentoxifylline et l’analogue hydrophile de vitamine E (trolox) qui permet à l’association d’inhiber l’expression de TGF-β1 au niveau de l’ARN messager et de la protéine. Cette action inhibitrice intervient au niveau transcriptionnel et conduit à une inhibition conséquente des cibles de la voie de signalisation TGF-β1/Smad (Col Iα1, FN1, PAI-1, CTGF), alors qu’elle semble sans effet sur la voie de signalisation Rho/ROCK. Pour la première fois, dans ces cellules issues de l’entéropathie radique, nous avons montré une surexpression de miR-210 ; microRNA induit par l’hypoxie. L’association pentoxifylline-trolox inverse la surexpression de miR-210 aussi bien dans les conditions normoxique que dans les conditions hypoxiques. L’implication de miR-210 dans l’entéropathie radique n’a pas été préalablement étudiée, néanmoins nous avons montré qu’un inhibiteur de miR-210 diminue l’expression de Col Iα1 dans ce modèle. L’effet anti-fibrosant exercé par l’association pentoxifylline-vitamine E est partiellement induit par l’inhibition de la cascade TGF-β1. L’inhibition de miR-210 est un deuxième mécanisme potentiel nécessitant d’autres investigations. Cette étude renforce les essais clinique antérieurs en montrant in vitro une synergie entre pentoxifylline et vitamine E et permettant de proposer cette association en première ligne thérapeutique dans la fibrose radio-induite. De plus, miR-210 est proposé comme une possible cible thérapeutique pour traiter la fibrose radio-induite. / Radiation-induced fibrosis is a serious late complication of radiotherapy. Pentoxifylline-vitamin E has proven effective and safe in clinical trials as treatment of fibrosis, while the molecular mechanism of its activity is yet unexplored. We showed efficacy of Pentoxifylline-vitamin E combination in radiation-induced enteropathy in a small clinical study. In parallel, using a unique in vitro model of primary smooth muscle cells isolated from intestinal samples isolated from humans with radiation enteropathy we showed that pentoxifylline and the hydrophilic analogous of vitamin E (trolox) synergize to inhibit TGF-β1 protein and mRNA expression. This inhibitory action is mediated at the transcriptional level and leads to subsequent inhibition of TGF-β1/Smad targets (Col Iα1, FN1, PAI-1, CTGF), while it has no effect on the Rho/Rock pathway. We have also demonstrated, for the first time, an overexpression of the hypoxia-induced microRNA miR-210 in the fibrotic cells. Pentoxifylline-trolox combination could reverse this miR-210 overexpression in normoxic and hypoxic conditions. While miR-210 has not been previously shown to be involved in radiation-induced enteropathy, we showed that miR-210 inhibitor could reduce mRNA expression of Col Iα1. The anti-fibrotic effect of combined pentoxifylline-vitamin E is at least in part mediated by inhibition of the TGF-β1 cascade. MiR-210 inhibition is another mechanism which needs further investigations. This study strengthens previous clinical data showing pentoxifylline-vitamin E synergy and supports its use as a first-line treatment of radiation-induced fibrosis. Also, it suggests miR-210 as a new potential therapeutic target for the treatment of this complication.
68

Avaliação do risco ecogenotoxicológico da utilização de corantes têxteis / Assessment of the ecogenotoxicologic risk of using textile dyes

Rocha, Otávio Pelegrino 11 October 2016 (has links)
Este trabalho teve como objetivo principal a avaliação do risco ecogenotoxicológico dos corantes Acid Black 210 e Disperse Violet 93, utilizados pelas indústrias têxteis e coureiras nacionais e internacionais. Para atingir este objetivo foi realizada uma abordagem integrada da avaliação da toxicidade utilizando a avaliação da permeabilidade através do Ensaio de Permeabilidade em Membrana Artificial Paralela (PAMPA), a avaliação do potencial genotóxico através do Ensaio do Cometa com células HepG2, a avaliação do potencial mutagênico do através do Teste de Ames com as linhagens de Salmonella typhimurium TA98 e TA100 na ausência e na presença de metabolização exógena (mistura S9), a avaliação do potencial embriotóxico através do Ensaio de Toxicidade Aguda com Embriões de Zebrafish (Danio rerio), e, por fim, juntando os dados disponíveis na literatura científica, a avaliação do risco ecogenotoxicológico da utilização deste corante têxtil. Devido à observação de ausência de toxicidade nos ensaios realizados e nas informações constantes da literatura científica, não há indícios de que o Acid Black 210 apresente ecogenotoxicidade, podendo ser considerado seguro à luz dos conhecimentos atuais. Ainda, este trabalho apresenta a avaliação do potencial genotóxico do corante Disperse Violet 93 através do Ensaio do Cometa e a avaliação do potencial embriotóxico deste corante através do Ensaio de Toxicidade Aguda com Embriões de Zebrafish (Danio rerio). Considerando que houve toxicidade morfofisiológica em embriões de zebrafish e que na literatura científica também consta sua mutagenicidade em linhagem de S. typhimurium YG1041, o Disperse Violet 93 necessita de avaliações nos demais níveis tróficos para que uma avaliação do risco seja realizada. Para finalizar, este trabalho apresenta a avaliação do potencial embriotóxico de efluente de curtume pré e pós-tratamento através do Ensaio de Toxicidade Aguda com Embriões de Zebrafish, onde o efluente pós-tratamento mostrou menor potencial embrio-tóxico, porém ambos apresentando (mesmo após diluições) coagulação de ovos fertilizados, edema do saco vitelínico, escoliose, má-formação da cauda e má-formação da bexiga natatória. Estes resultados ressaltam a importância da realização de estudos toxicológicos visando fornecer subsídios para a realização de avaliações do risco do uso de corantes, já que estes se encontram em exposição constante aos seres vivos e ao meio ambiente / This study had as main objective the evaluation of the ecogenotoxicologic risk of the Acid Black 210 and Disperse Violet 93 dyes, used by national and international textile and tanneries industries. To achieve this goal was accomplished an integrated approach to evaluate the risk assessment with the permeability through the Parallel Artificial Membrane Permeability Assay (PAMPA), the evaluation of the genotoxic potential using the Comet Assay with HepG2 cells, the assessment of the mutagenic potential through the Ames Assay with the Salmonella typhimurium TA98 and TA100 strains in the absence and presence of exogenous metabolism (S9), the evaluation of the embryo-toxic potential through the Zebrafish (Danio rerio) Embryo Acute Toxicity Test, and, finally, joining the data available in the scientific literature, the evaluation of ecogenotoxicologic risk of using this textile dye. Due to the observation of the absence of toxicity in the testes performed and the information available in the scientific literature, there is no indication that the Acid Black 210 dye has any ecogenotoxicity, and it can be considered safe in the light of current knowledge. Additionally, this study presents the evaluation of the genotoxic potential of the Disperse Violet 93 dye by the Comet Assay and the assessment of embryo-toxic potential of this dye through the Zebrafish (Danio rerio) Embryo Acute Toxicity Test. Considering the observed morphophysiological toxicity in zebrafish embryos and the mutagenicity in S. typhimurium YG1041 strain described by the scientific literature, the Disperse Violet 93 dye needs more studies in other trophic levels to perform its risk assessment. Finally, this study presents the assessment of embryo-toxic potential of effluent pre tannery and aftercare through the Zebrafish (Danio rerio) Embryo Acute Toxicity Test, where the post-treatment effluent showed less embryo-toxic potential, but both presented (even after dilution) coagulation of fertilized eggs, yolk sac edema, scoliosis, malformation of the tail and malformation of the swim bladder. These results highlight the importance of conducting toxicological studies to provide input data for conducting risk assessments of the use of dyes, as they are in constant exposure to the living organisms and the environment
69

Determinação da taxa de sedimentação na foz do rio Amazonas usando o 210Pb como geocronômetro

Nery, José Reinaldo Cardoso [UNESP] 27 March 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-27Bitstream added on 2014-06-13T21:04:03Z : No. of bitstreams: 1 nery_jrc_dr_rcla.pdf: 10110877 bytes, checksum: 15e1158067ecc6df791bd71934386c41 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Três testemunhos de sedimentos foram amostrados na foz do rio Amazonas, na região denominada canal Norte, com o objetivo de determinar a taxa de sedimentação utilizando o 210Pb como geocronômetro. Teores de 210Po e 210Pb foram determinados nas amostras de sedimentos, através de espectrometria alfa. Para determinar o excesso de 210Pb presente nos sedimentos, foi necessária a quantificação do 238U, procedimento que foi realizado por espectrometria gama. Além dessas análises, procedeu-se a caracterização física e química dos sedimentos, assim como foram determinadas as características básicas da água, com o objetivo de subsidiar a interpretação dos resultados obtidos para os radionuclídeos. Testes estatísticos de correlação foram realizados para indicar o grau de associação entre as características dos sedimentos analisados. Os resultados permitiram a identificação e determinação de duas taxas de sedimentação para cada perfil analisado, provavelmente devido a mudanças ocorridas no modelo de sedimentação daquela região. Foram determinadas taxas de sedimentação no intervalo de 0,45 a 2,51 g/cm2.ano, correspondendo ao intervalo de 0,42 a 1,76 cm/ano. / Three sediment cores were obtained from the estuary of the Amazon river, in the region called canal Norte, with the objective to determine the sedimentation rates using 210Pb as geochronometer. The cores were analyzed for 210Po by alpha spectrometry on intention to determine 210Pb in sediments. To obtain information about the excess 210Pb, measurements of 238U content were performed by gamma spectrometry. In addition to these analyzes, physical and chemical characterization of the sediments were evaluated, as well it was performed the basic characteristics of the water in order to subsidize the interpretation of the obtained results for the radionuclides. Statistical tests of correlation had been carried through to indicate the association degree between the characteristics of the analyzed sediments. The results allowed to the identification and determination of two sedimentation rates for each analyzed profile, probably due to changes in the model of sedimentation occurred in that region. The obtained sedimentation rates varied from 0,45 to 2,51 g/cm2.year, corresponding to a range of 0,42 to 1,76 cm/year.
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Evolução temporal das distribuições dos radionuclídeos naturais U-238, Th-234, Ra-226, Ra-228, Pb-210 e Po-210 no estreito de Bransfield, Península Antártica / Temporal evolution of natural radionuclides distributions sup(238)U, sup(234)Th, sup(226)Ra, sup(228)Ra, sup(210)Pb and sup(210)Po in the Bransfield strait, Antartica Peninsula

LAPA, FLAVIA V. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:02Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:49Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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