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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.
1

The Effect of Environmental Contaminants on Mating Dynamics and Population Viability in a Sex-Role-Reversed Pipefish

Partridge, Charlyn G. 2009 December 1900 (has links)
Understanding how anthropogenic activity impacts the health and viability of wildlife populations is one of the most important tasks of environmental biology. A key concern related to bi-products of human activity is the accumulation of environmental pollutants within aquatic environments. Pollutants such as endocrine disruptors and heavy metals have the potential to impact both human and wildlife populations in contaminated areas. While much research has focused on how these compounds impact natural selection processes, such as viability and reproduction, their effect on sexual selection processes is not as clear. The goal of this dissertation was to address how environmental contaminants impact sexual selection processes in a sex-role reversed pipefish and evaluate how these effects may impact long-term population viability. Here we show that short periods of exposure to environmentally relevant concentrations of a synthetic estrogen result in male pipefish with female-like secondary sexual traits. While these males are capable of reproduction, exposed males are discriminated against by females in mate choice tests. In natural populations, this type of discrimination could reduce male mating opportunities, potentially reducing their reproductive success. In an additional component of this dissertation, it was discovered that pipefish populations around Mobile Bay, specifically Weeks Bay, are currently being exposed to significantly elevated levels of mercury. These populations are genetically distinct from coastal populations but moderate levels of gene flow occur among sites, and gene flow between contaminated and non-contaminated population may be influencing how environmental contaminants are impacting genetic diversity and population viability. In the case of endocrine disruptors, migration between contaminated and non-contaminated sites may negatively impact population viability. Morphological traits induced with exposure to contaminants may be maintained for extended periods of time, therefore, the effect the exposed phenotype has on mating dynamics and sexual selection could be carried to non-contaminated sites if exposed individuals move to new populations. On the other hand, immigration of individuals from non-contaminated sites into contaminated areas may help maintain genetic diversity within exposed populations. In conclusion, the work presented in this dissertation shows that the presence of environmental toxins can significantly impact sexual selection processes, which in turn can have profound effects on the viability and future evolutionary trajectory of populations. Future work in this area should not only address how these toxins impact individual fitness, but should also address how population structure may be influencing the severity of these compounds on natural populations.
2

Utgör användning av p-piller ett hot mot livskraftiga grodpopulationer? : Etinylöstradiols och levonorgestrels effekter hos arterna Xenopus leavis, Xenopus tropicalis och Rana temporaria

Balck, Marianne January 2013 (has links)
En eskalerande minskning hos grodpopulationer och grodarter har skett världen över sedan 1980. Minskningen har påverkats av flera faktorer, bland annat utsläpp av endokrina ämnen till vattendrag. Endokrina ämnen är naturliga och syntetiska hormoner och kemikalier som stör människors och djurs hormonsystem. Syntetiska hormoner finns i p-piller och andra preventivmedel och hormonerna släpps ut i vattendrag via urinen. Det har visats att grodor påverkas av de syntetiska hormonerna etinylestradiol och levonorgestrel som finns i p-piller. Den här litteraturstudien syftar till att undersöka vilka effekter de två hormonerna har på modellarterna Xenopus laevis och Xenopus trolpicalis och på svenska grodarter såsom Rana temporaria. Effekterna är främst förändrad könskvot, med honor i majoritet, samt minskad fertilitet. Fertiliteten försämras genom missbildade könsorgan, genom att äggen mognar långsammare och honor kan bli sterila med avsaknad av äggledare. Hormonexponering kan leda till försenad metamorfos och det kan bli en högre mortalitet hos juvenila grodor. Även hormonuttryck kopplade till reproduktion och fertilitet kan påverkas av hormonexponering. Dock behövs mer forskning, särskilt i fält då mestadels experimentella studier gjorts hittills i laboratorier. Hormonutsläpp är en bidragande faktor till att sex av Sveriges åtta grodarter är rödlistade och i världen handlar det om tusentals arter. Även den så kallade cocktail effekten, det vill säga de effekter flera olika ämnen skapar tillsammans, bör undersökas närmare.
3

Pharmacokinetics and pharmacodynamics of protein turnover and production in vivo

Kim, Jonghan January 2004 (has links)
No description available.
4

Kondom eller P-piller? : En livscykelanalys med fokus på miljöpåverkan / Condoms or birth control pills? : A life cycle analysis focused on the environmental impacts

Legind, Ann-Sofie January 2020 (has links)
Det finns ett ökat intresse för klimatet och miljöpåverkan hos gemene man och hos många en vilja att leva med en mer miljövänlig livsstil. När det kommer till preventivmedel och att välja det alternativ som passar en bäst, dessutom med hänsyn till vad som är det bästa för miljön, så är det en djungel där ute. Även preventivmedelsrådgivare upplever en bristande kunskap för att kunna ge bra råd inom ämnet. Det här arbetet skrevs för att jämföra miljöpåverkan mellan användandet av p-piller och kondom. Detta gjordes med hjälp av en kvalitativ litteraturstudie som i senare steg kompletterades med en kvantitativ fallstudie med fokus på livscykelanalys av båda produkterna. Livscykelanalyserna gjordes i två steg, först togs ett processträd fram med hjälp av litteraturstudien och dessa gjorde sedan grunden för livscykelanalysen som genomfördes med mjukvaran ReCiPe i SimaPro. Resultatet av studien blev att kondomen visar på större miljöpåverkan i förhållande till användandet av p-piller. Dock saknas det i ReCiPe den påverkan som hormonet i p-piller på både land- och marin miljö ger, vilket lett till att resultatet inte är helt tillförlitligt och det riskerar vara en betydande felkälla. / There is a growing interest for the climate and the environmental effect the average person has on its surroundings and many people choose to live more environmentally friendly. It’s a jungle out there when it comes to birth control and choosing the option that suits one best but also is the most environmentally sustainable option. Midwifes have expressed that they experience a lack of knowledge amongst themselves as to what contraceptive is the most environmentally friendly. This thesis compared the environmental effects between using the contraceptive pill or condom as birth control. This was done with the help of a qualitative literature study which later on was complemented with a quantitative case study focusing on lifecycle analysis of both the products. The lifecycle analysis was executed in two stages, whereas the first stage was developing a process tree with the help of the literature study. This was later used as the foundation for the second stage, which was the lifecycle analysis done with the help of the ReCiPe data in SimaPro. The results showed that the condom had a higher impact on the environment relative to the contraceptive pill. Although, from the ReCiPe data there were no indications that the hormones that are released from the contraceptive pill would have any effect on the land or marine environment. This lack of data poses a risk of a major fault in the results as the hormonal effects on the environment is the main issue with the pill.
5

Organ and primary culture of medaka (Oryzias latipes) testis: Test systems for the analysis of cell proliferation and differentiation / Organ und Primärzellkultur von Medaka Testis: Test Systeme zur Untersuchung des Zellproliferation und Zelldifferenzierung

Song, Miyeoun 22 June 2003 (has links) (PDF)
In cultured medaka testis fragments, cells remained viable for the entire culture period (17h), and spermatids that developed from spermatocytes were viable and motile. Primary cultures were characterized over a period of two days with respect to cell viability and the distribution of adherent and suspended cells. These two cell populations were maintained in dynamic equilibrium in vitro for several days. Proliferating cells were predominant among clusters of suspended cells, as determined by BrdU labeling, and CFSE and propidium iodide PI labeling. Based on cytological criteria, the proliferating cells were mostly spermatogonia and possibly also preleptotene spermatocytes. Differentiation of spermatocytes into spermatids or spermatozoa was also observed, mainly among the suspended cells. These results suggest that the organ and primary culture systems are suitable systems for studying the effects of substances that interfere with spermatogenesis in the medaka, a model vertebrate. The organ and primary culture systems were used to analyze the effects of a synthetic estrogen, EE2, on cell proliferation in medaka testis. Both organ and primary culture were suitable for this purpose consistently small concentrations (0.01 and 1 nM) of EE2 stimulated cell proliferation slightly, while higher concentrations (100 nM) had an inhibitory effect. To investigate the effect of phytoestrogens on cell proliferation in spermatogenesis, selected flavonoids [genistein (1, 10, 100 µg/ml), quercetin (0.01, 1, 100 µM), and 8-prenylnarigenin (0.001, 0.1, 1, 10 µM)] were added to medaka testis primary cultures. Genistein and quercetin inhibited cell proliferation in the cultures while 8-prenylnarigenin had no effect. In a second series of experiments the addition of genistein (10 µg/ml) to primary cultures significantly inhibited both cell proliferation and cell differentiation as determined by flow cytometry using CFSE/PI labeling.
6

Organ and primary culture of medaka (Oryzias latipes) testis: Test systems for the analysis of cell proliferation and differentiation

Song, Miyeoun 18 July 2003 (has links)
In cultured medaka testis fragments, cells remained viable for the entire culture period (17h), and spermatids that developed from spermatocytes were viable and motile. Primary cultures were characterized over a period of two days with respect to cell viability and the distribution of adherent and suspended cells. These two cell populations were maintained in dynamic equilibrium in vitro for several days. Proliferating cells were predominant among clusters of suspended cells, as determined by BrdU labeling, and CFSE and propidium iodide PI labeling. Based on cytological criteria, the proliferating cells were mostly spermatogonia and possibly also preleptotene spermatocytes. Differentiation of spermatocytes into spermatids or spermatozoa was also observed, mainly among the suspended cells. These results suggest that the organ and primary culture systems are suitable systems for studying the effects of substances that interfere with spermatogenesis in the medaka, a model vertebrate. The organ and primary culture systems were used to analyze the effects of a synthetic estrogen, EE2, on cell proliferation in medaka testis. Both organ and primary culture were suitable for this purpose consistently small concentrations (0.01 and 1 nM) of EE2 stimulated cell proliferation slightly, while higher concentrations (100 nM) had an inhibitory effect. To investigate the effect of phytoestrogens on cell proliferation in spermatogenesis, selected flavonoids [genistein (1, 10, 100 µg/ml), quercetin (0.01, 1, 100 µM), and 8-prenylnarigenin (0.001, 0.1, 1, 10 µM)] were added to medaka testis primary cultures. Genistein and quercetin inhibited cell proliferation in the cultures while 8-prenylnarigenin had no effect. In a second series of experiments the addition of genistein (10 µg/ml) to primary cultures significantly inhibited both cell proliferation and cell differentiation as determined by flow cytometry using CFSE/PI labeling.
7

Cultivo de Landoltia punctata na remoção de desreguladores endócrinos e no polimento de esgoto sanitário em lagoa com recirculação /

Zanetoni Filho, José Antônio. January 2019 (has links)
Orientador: Liliane Lazzari Albertin / Resumo: A situação de escassez de recursos financeiros destinados ao tratamento e coleta de esgotos municipais, no Brasil, torna essencial a busca por tecnologias de tratamento que priorizem baixos custos de instalação e operação. Além da negligência que existe no tratamento de esgotos, os métodos utilizados, muitas vezes, não são capazes de remover os micropoluentes que estão presentes nos esgotos domésticos. Os micropoluentes podem ser desde fármacos, que são expelidos na urina ou descartados de maneira inadequada, a hormônios naturais ou sintéticos. Esse trabalho consistiu em realizar um processo de polimento do esgoto sanitário da cidade de Ilha Solteira – SP. O sistema de polimento é constituído por dois tanques, onde foi cultivada a macrófita Landoltia punctata. Foi também avaliado e feito a recirculação do efluente, no tratamento de esgoto. Neste sistema de polimento, foram avaliadas as eficiências de tratamento para os parâmetros de DBO, DQO, NT, NO3-, PT e ST. As maiores eficiências de remoção para DBO, DQO, NT, NO3-, PT e ST foram de 66,35%, 59,08%, 26,76%, 28,38%, 6,85% e 40,08%. Outro aspecto avaliado foi a taxa de crescimento da macrófita cultivada em esgoto sanitário. As maiores taxas de crescimento relativo foram de 3,84 e 3,17 g.m-2.d-1 MS. Considerando a presença de desreguladores endócrinos (DEs) no efluente da Estação de Tratamento de Esgoto (ETE) de Ilha Solteira, foi analisado a absorção dos estrógenos 17α-etinilestradiol (EE2) e o estriol (E3) pela macrófita, av... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The scarcity of financial resources for the treatment and collection of municipal wastewater in Brazil makes search for treatment technologies essential with low installation and operation costs. In addition, the methods used are often not able to remove the micropollutants that are present in domestic sewage. Micropollutants can range from drugs that are expelled in the urine or inappropriately discarded to natural or synthetic hormones. This work consisted of a process to polishing the sanitary sewage of the city of Ilha Solteira - SP. The treatment system consists of two tanks, where the macrophyte Landoltia punctata was grown. In one of the tanks, a recirculation system was performed. In this polishing system, the treatment efficiencies for the BOD, COD, TN, NO3-, TP and ST parameters were evaluated. The highest removal efficiencies for BOD, COD, TN, NO3-, TP and ST were 66,35%, 59,08%, 26,76%, 28,38%, 6,85% and 40,08%. Another aspect evaluated was the growth rate of the macrophyte. The highest relative growth rates were 3.84 and 3.17 g.m-2.d-1 MS. Considering the presence of endocrine disrupters (DEs) in the effluent from the Sewage Treatment Plant (ETE) in Ilha Solteira - SP, 17α-ethinyl estradiol (EE2) and estriol (E3) were analyzed on the plant to evaluate possible risks on the reuse of the biomass. The maximum achieved efficiencies for removal of E3 and EE2 were 83.63% and 83.50%, respectively. The recirculation tank was more effective at removing E3, while the non-r... (Complete abstract click electronic access below) / Mestre
8

Monitoração de resíduos dos hormônios 17\'alfa\'-etinilestradiol, 17\'beta\'-estradiol e estriol em águas de abastecimento urbano da cidade de Piracicaba, SP / Monitoring of residues of hormones 17\'alfa\'-ethinylestradiol, 17\'beta\'-estradiol and estriol in urban water supply from the city of Piracicaba, SP

Torres, Nádia Hortense 25 August 2009 (has links)
A ocorrência de fármacos residuais no meio ambiente pode levar a efeitos adversos, tanto em organismos aquáticos como em terrestres. Os fármacos, tanto humanos como de uso veterinário, são absorvidos pelo organismo e estão sujeitos a reações metabólicas e, uma quantidade significativa dessas substâncias, tanto a original como seus metabólitos, são excretadas. Por não serem facilmente biodegradáveis, terem propriedades farmacológicas danosas quando administrados indevidamente, através de água contaminada, é crescente a preocupação com o destino destes fármacos residuais, principalmente com relação à avaliação de risco ambiental. A ocorrência destes resíduos, principalmente em águas superficiais e sistemas de abastecimento, vem sendo objeto de estudos em diversos países, principalmente na Europa. Por isso, a detecção, a eliminação e a investigação do destino destes compostos estrógenos em ecossistemas aquáticos têm tido prioridade na química ambiental. Estes produtos são encontrados nos corpos d\'água em baixas concentrações, de \'mü\'g L-1 a \'eta\'g L-1 e, mesmo assim, podem afetar os organismos por meio da bioacumulação. Estudos toxicológicos relacionados a efeitos crônicos em organismos expostos, são escassos. O objetivo do projeto foi adaptar e validar a metodologia analítica, e monitorar a presença de resíduos de hormônios nas águas dos Rios Corumbataí e Piracicaba e amostras de água de abastecimento da cidade de Piracicaba, SP, Brasil. Foram coletadas amostras de água bruta dos Rios Piracicaba e Corumbataí e água de abastecimento residencial da cidade de Piracicaba, SP, no período de novembro de 2007 a abril de 2009. Dentre os hormônios estudados estão o 17\'alfa\'-etinilestradiol (17\'alfa\'-EE2), 17\'beta\'-estradiol (17\'beta\'-E2) e estriol (E3). O método foi baseado na extração em fase sólida (SPE) e cromatografia líquida de alta eficiência (HPLC-DAD) / The occurrence of drug residues in the environment may lead to adverse effects, both on land and aquatic organisms. The drugs, for human and veterinary use, are absorbed by the organism and are subjected to metabolic reactions and a significant amount of these substances, both the original and its metabolites are excreted. By being not easily biodegradable and by having harmful pharmacological properties when administered through contaminated water, there is a growing concern about the fate of these residual drugs, especially in respect to the assessment of environmental risks. The occurrence of these residues, especially in surface Waters and water supplies has been the subject of studies in several countries, mainly in Europe. Therefore, detection, investigation and disposal of the fate of these estrogens compounds in aquatic ecosystems have a high priority in the field of environmental chemistry. These products are found in water bodies in low concentrations, from \'mü\'g L-1 a \'eta\'g L-1 and can still affect the organisms due to bioaccumulation. Toxicological studies related to chronic effects in the exposed organisms are scarce. The goals of this project was to adapt and validate the analytical methodology, and monitor the presence of hormone residues in the Waters of the Corumbataí and Piracicaba rivers and samples of water supply from the city of Piracicaba, SP, Brazil. We collected samples of raw water from the rivers of Piracicaba and Corumbataí and residential water supply from the city of Piracicaba in the period November 2007 to April 2009. Among the hormones studied are the 17\'alfa\'-ethinylestradiol (17\'alfa\'-EE2), 17\'beta\'-estradiol (17\'beta\'-E2) and estriol (E3). The method is based on solid phase extraction (SPE) and high performance liquid chromatography (HPLC-DAD)
9

Monitoração de resíduos dos hormônios 17\'alfa\'-etinilestradiol, 17\'beta\'-estradiol e estriol em águas de abastecimento urbano da cidade de Piracicaba, SP / Monitoring of residues of hormones 17\'alfa\'-ethinylestradiol, 17\'beta\'-estradiol and estriol in urban water supply from the city of Piracicaba, SP

Nádia Hortense Torres 25 August 2009 (has links)
A ocorrência de fármacos residuais no meio ambiente pode levar a efeitos adversos, tanto em organismos aquáticos como em terrestres. Os fármacos, tanto humanos como de uso veterinário, são absorvidos pelo organismo e estão sujeitos a reações metabólicas e, uma quantidade significativa dessas substâncias, tanto a original como seus metabólitos, são excretadas. Por não serem facilmente biodegradáveis, terem propriedades farmacológicas danosas quando administrados indevidamente, através de água contaminada, é crescente a preocupação com o destino destes fármacos residuais, principalmente com relação à avaliação de risco ambiental. A ocorrência destes resíduos, principalmente em águas superficiais e sistemas de abastecimento, vem sendo objeto de estudos em diversos países, principalmente na Europa. Por isso, a detecção, a eliminação e a investigação do destino destes compostos estrógenos em ecossistemas aquáticos têm tido prioridade na química ambiental. Estes produtos são encontrados nos corpos d\'água em baixas concentrações, de \'mü\'g L-1 a \'eta\'g L-1 e, mesmo assim, podem afetar os organismos por meio da bioacumulação. Estudos toxicológicos relacionados a efeitos crônicos em organismos expostos, são escassos. O objetivo do projeto foi adaptar e validar a metodologia analítica, e monitorar a presença de resíduos de hormônios nas águas dos Rios Corumbataí e Piracicaba e amostras de água de abastecimento da cidade de Piracicaba, SP, Brasil. Foram coletadas amostras de água bruta dos Rios Piracicaba e Corumbataí e água de abastecimento residencial da cidade de Piracicaba, SP, no período de novembro de 2007 a abril de 2009. Dentre os hormônios estudados estão o 17\'alfa\'-etinilestradiol (17\'alfa\'-EE2), 17\'beta\'-estradiol (17\'beta\'-E2) e estriol (E3). O método foi baseado na extração em fase sólida (SPE) e cromatografia líquida de alta eficiência (HPLC-DAD) / The occurrence of drug residues in the environment may lead to adverse effects, both on land and aquatic organisms. The drugs, for human and veterinary use, are absorbed by the organism and are subjected to metabolic reactions and a significant amount of these substances, both the original and its metabolites are excreted. By being not easily biodegradable and by having harmful pharmacological properties when administered through contaminated water, there is a growing concern about the fate of these residual drugs, especially in respect to the assessment of environmental risks. The occurrence of these residues, especially in surface Waters and water supplies has been the subject of studies in several countries, mainly in Europe. Therefore, detection, investigation and disposal of the fate of these estrogens compounds in aquatic ecosystems have a high priority in the field of environmental chemistry. These products are found in water bodies in low concentrations, from \'mü\'g L-1 a \'eta\'g L-1 and can still affect the organisms due to bioaccumulation. Toxicological studies related to chronic effects in the exposed organisms are scarce. The goals of this project was to adapt and validate the analytical methodology, and monitor the presence of hormone residues in the Waters of the Corumbataí and Piracicaba rivers and samples of water supply from the city of Piracicaba, SP, Brazil. We collected samples of raw water from the rivers of Piracicaba and Corumbataí and residential water supply from the city of Piracicaba in the period November 2007 to April 2009. Among the hormones studied are the 17\'alfa\'-ethinylestradiol (17\'alfa\'-EE2), 17\'beta\'-estradiol (17\'beta\'-E2) and estriol (E3). The method is based on solid phase extraction (SPE) and high performance liquid chromatography (HPLC-DAD)
10

The implications of wicked problems for the legitimacy of European environmental policy development : the case of environmental risks from the pharmaceutical endocrine disrupter, 17α-ethinyl oestradiol, under the European Water Framework Directive

Gardner Le Gars, Joanne Claire January 2018 (has links)
The issue of environmental risks from the pharmaceutical endocrine disrupter 17 alpha-ethinyl oestradiol (EE2), which is an active ingredient in the contraceptive pill, confronts government responsibilities for citizens' health with potential environmental risks from its presence in aquatic ecosystems. Further to a risk appraisal process conducted under the Water Framework Directive (WFD) between 2006 and 2012, the European Commission recommended the imposition of an environmental quality standard for EE2. In 2013, this recommendation was rejected by politicians. The outcome was both contested and commended. The UK Government was particularly vehement in its opposition and claimed that the risk assessment process for EE2 was not robust. The UK Government also insisted that it had swayed opinion of other EU Member States to convince them that action for EE2 was not proportionate given the extremely elevated costs of risk control options. At the present time, environmental policy for EE2 and other endocrine disrupters remains resolutely ineffective. Despite three distinct policy interventions recommending precautionary action for EE2 during the past twenty years, emissions of this potent, oestrogenic endocrine disrupter continue unabated. This thesis explains why European politicians rejected the European Commission’s risk governance recommendations for EE2 in 2013 under the Water Framework Directive. This comprises its principal empirical contribution. A novel analytical framework which draws on insights from the policy sciences, risk governance and wicked problems literature is developed. This framework is employed to determine whether the policy outcome for EE2, and the decision-making processes that preceded it, were legitimate. The research findings in this respect advance understanding of the implications of specific properties of wicked problems, of which it is argued, EE2 is an example, for the legitimacy of decision-making processes during the risk appraisal and political phases of policy development in Europe. This comprises the principle theoretical contribution of the thesis. Recommendations to promote more effective and legitimate policy development for wicked problems in similar multi-level governance contexts are also made.

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