Dissertations / Theses on the topic 'Genetic pollution'
To see the other types of publications on this topic, follow the link: Genetic pollution.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Genetic pollution.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Pedrosa, João André da Mota. "Microevolutionary dynamics and genetic erosion in pollution-affected Chironomus populations." Doctoral thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/17941.
Abstract:
Doutoramento em BiologiaAs populações que vivem em ecossistemas de água doce extremamente contaminados por metais podem estar sujeitas a forte seleção e deriva genética. Este processo de erosão genética poderá ameaçar a sua sobrevivência a longo prazo, uma vez que a capacidade de adaptação das populações a alterações das condições ambientais está diretamente relacionada com os níveis de diversidade genética. Neste sentido, a procura por novos bioindicadores, que aumentem a relevância ecológica da avaliação de risco ambiental, tem levado a um crescente interesse pela toxicologia evolutiva e por medidas de diversidade genética. O trabalho aqui apresentado tem como objetivo último compreender de que forma os níveis de diversidade genética da espécie modelo em ecotoxicologia Chironomus riparius (Meigen) podem ser usados como indicadores de qualidade ecológica de sistemas de água doce. Para tal, avaliaram-se respostas microevolutivas à contaminação histórica por metais em populações de C. riparius, incluindo determinação dos níveis de diversidade genética, adaptação genética a metais e potenciais custos de fitness. A diversidade genética foi estimada com base na variação de sete marcadores de microssatélites enquanto que a adaptação genética a metais e potenciais custos de fitness foi avaliada através da tolerância aguda e crónica a diferentes stressores ambientais, medidas de balanço energético e mecanismos de defesa após manter as diferentes populações durante várias gerações em condições laboratoriais controlo. Por fim, as respostas microevolutivas de C. riparius à contaminação por metais foram comparadas com a diversidade e composição das comunidades de macroinvertebrados. Para determinar a relação de causa-efeito entre respostas microevolutivas e contaminação, os efeitos da poluição por metais foram investigados em diferentes locais historicamente contaminados por metais e comparados com várias referências. Os resultados demonstraram elevados níveis de diversidade genética e uma considerável homogeneidade genética entre as populações monitorizadas em condições naturais. No entanto, observaram-se evidências de adaptação genética a metais nas populações de locais contaminados, incluindo maior tolerância à exposição aguda por metais e elevados níveis basais de glutationas e metalotioninas que possivelmente aumentam a capacidade de resposta das populações à exposição a metais. Além do mais, observaram-se maiores custos energéticos em populações de locais contaminados quando expostas a metais, enquanto que uma das populações de locais contaminados apresentou também custos de fitness em condições controlo. Finalmente, verificou-se que a diversidade e composição das comunidades de macroinvertebrados dos locais contaminados foi fortemente afetada e muitos grupos taxonómicos sensíveis à contaminação foram eliminados e substituídos por outros mais oportunistas, tais como C. riparius. De um modo geral, as medidas de diversidade genética de populações naturais de C. riparius não mostraram ser ferramentas de biomonitorização particularmente vantajosas per se uma vez que não refletiram as respostas microevolutivas das diferentes populações à poluição histórica por metais. Tal facto poderá estar relacionado com a elevada densidade populacional e dinamismo da espécie em condições naturais, uma vez que se observou uma considerável perda de diversidade genética quando as populações foram mantidas em laboratório durante períodos de tempo relativamente longos. Não obstante, algumas linhas de evidência do presente trabalho sugerem o uso de medidas de diversidade genética de C. riparius em diversas situações experimentais como sejam: deteção de hibridização interespecífica; estabelecimento de níveis mínimos de diversidade genética em laboratório; e, finalmente, uso integrativo de medidas de diversidade genética em programas de biomonitorização com um foco mais direcionado para os efeitos ao nível da comunidade de macroinvertebrados. Os resultados apresentados pretendem estimular a discussão acerca da adequabilidade de C. riparius como espécie modelo em toxicologia evolutiva bem como a sensibilidade e robustez das medidas de diversidade genética como indicadores de qualidade ambiental em avaliação de risco ecológico.
Natural populations inhabiting heavily metal impacted freshwater ecosystems may face intense selection and genetic drift that conduct populations to severe reductions of genetic diversity, the so-called process of genetic erosion. Because the ability of populations to adapt to environmental change is directly related to the levels of genetic diversity, contaminant-driven genetic erosion may threaten the long-term survival of populations. The search for more robust and context-driven bio-indicators that add ecological relevance to the environmental risk assessments has increased interest in evolutionary toxicology and measures of genetic diversity. The research described in the present thesis was performed with the ultimate goal of understanding whether the levels of genetic diversity of the model ecotoxicological species Chironomus riparius (Meigen) may be used as ecological indicators of the health of freshwater systems. For that, an integrative study was undertaken investigating microevolutionary responses of C. riparius towards historical metal pollution. This included assessments of levels of genetic diversity as well as determination of genetic adaptation to metals and associated fitness costs. Genetic diversity was estimated based on the variation of seven microsatellite markers. Genetic adaptation and associated fitness costs were investigated through acute and chronic exposures to different environmental stressors, measurements of energy budget and biochemical mechanisms of tolerance to metals, after maintaining populations for several generations under standard laboratory conditions. Microevolutionary responses of C. riparius to metal pollution were, afterwards, compared with macroinvertebrate diversity and composition metrics. To draw general conclusions of causal-relationship between microevolutionary responses and pollution history, effects were investigated across multiple metal polluted and reference site. Globally, the levels of genetic diversity were globally high and there was a remarkable genetic homogeneity among all C. riparius populations in the field. However, C. riparius populations from metal polluted sites showed signs of genetic adaptation to metals as suggested by the increased tolerance to acute concentrations of metal and high basal levels of glutathiones and metallothioneins that likely enhance the fitness of populations to cope with metal toxicity. Furthermore, populations from metals contaminated sites had higher energetic costs when exposed to metals and one of the populations from contaminated sites showed also a poorer performance under control clean conditions. Finally, diversity and composition of macroinvertebrate communities from metal polluted sites was strongly affected and many sensitive taxonomic groups were eliminated and replaced by more opportunistic ones such as C. riparius. Overall, measures of genetic diversity of C. riparius natural populations do not seem to be particularly advantageous biomonitoring tools per se once they did not reflect the underlying microevolutionary responses of natural populations to historical metal pollution. This is likely because of the large population densities together with the highly dynamic nature of C. riparius in the field as we observed genetic erosion in population reared under laboratory conditions over relatively long periods of time. However, several lines of evidence indicate that measures of genetic diversity may accrue valuable information in several experimental situations: detection of interspecific hybridization; establishment of minimum levels of genetic diversity in laboratory-reared C. riparius populations; finally, integrative use of measures of genetic diversity in biomonitoring programs with more community-level focus. The results presented in this thesis aim to stimulate discussion on the suitability of C. riparius as a model species in evolutionary ecotoxicology studies as well as the sensitivity and robustness of genetic diversity measures as indicators of environmental quality in ecological risk assessment.
2
Lind, Emma. "Genetic response to pollution in sticklebacks; natural selection in the wild." Doctoral thesis, Stockholms universitet, Zoologiska institutionen, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-89486.
Abstract:
The last century, humans have been altering almost all natural environments at an accelerating rate, including the Baltic Sea that has highly eutrophicated areas and many coastal industries such as Pulp-mills. For animals living in a habitat that changes there are basically two alternatives, either to cope with the change or become locally extinct. This thesis aims to investigate if recent anthropogenic disturbance in the Baltic Sea can affect natural populations on a genetic level through natural selection. First, we found a fine-scale genetic structure in three-spine sticklebacks (Gasterosteus aculeatus) populations along the Swedish coast (paper I), indicating limited gene-flow between populations in geographic proximity. Different genetic markers, specifically Amplified Fragment Lenght Polymorpism (AFLP, and microsatellites, gave different results, highlighting the heterogeneous character of genomes which demonstrates that it is important to choose a genetic marker that is relevant for the question at hand. With a population genomic approach, and a multilocus genetic marker (AFLP), we detected convergent evolution in genotype composition in stickleback populations living in environments affected by pulp-mill effluent (paper II) and in highly eutrophicated environments (paper III), compared to adjacent reference populations. We found loci, in both studies (paper II, III), that were different from a neutral distribution and thus probably under divergent selection for the habitat differences investigated. The selective effect from pulp-mill effluents were more pronounced, but the two different habitats had mutual characters (AFLP loci). In paper IV, we converted five anonymous AFLP loci to sequenced markers and aligned them to the stickleback genome. Four out of five loci aligned within, or close to, coding regions on chromosome I, chromosome VIII, chromosome XIX and chromosome XX. One of the loci, located on chromosome VIII and identified as under divergent selection in both paper II and III, has been identified in other studies as to be under selection for fresh water adaptation, including Baltic Sea stickleback populations. In conclusion, anthropogenic alterations of natural environments can have evolutionary consequences, probably adaptive, for the animals living there and the evolutionary response exhibited by natural populations can be very fast.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 3: Manuscript. Paper 4: Manuscript.
3
Souleman, Dima. "Genetic consequences of colonization of a metal-polluted environment, population genetics and quantitative genetics approaches." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10006/document.
Abstract:
Les habitats naturels sont de plus en plus détruits et fragmentés par l'expansion urbaine et les activités humaines. La fragmentation des espaces naturels et agricoles par les bâtiments et les nouvelles infrastructures affecte la taille, la connectivité et la qualité des habitats. Les populations d’organismes vivants sur ces territoires anthropisés sont alors plus isolées. Or, la différenciation entre populations d’un même organisme dépend de processus démographiques et génétiques tels que la dérive génétique, le flux génétique, la mutation et la sélection naturelle. La persistance et le développement des populations dans des conditions environnementales modifiées dépendent de mécanismes de tolérance. Dans ce contexte, l'introduction de contaminants tels que des métaux dans l'environnement peut influencer l'évolution des plantes et des animaux en modifiant les forces évolutives et en créant des différences entre populations. Dans ce travail, l’attention a été portée sur les conséquences génétiques de la pollution métallique sur deux espèces, le ver de terre Lumbricus terrestris et une plante modèle Arabidopsis halleri. Deux approches différentes ont été utilisées pour étudier la réponse génétique à la contamination métallique : une approche de génétique des populations chez L. terrestris et une approche de génétique quantitative chez A. halleri. Tout d’abord, il s’est agi d’identifier et de valider de nouveaux marqueurs microsatellites chez L. terrestris. Ensuite, ces marqueurs ont été utilisés afin de caractériser la diversité génétique neutre chez des vers collectés sur des sites agricoles et urbanisés. Parallèlement, l'architecture génétique de la tolérance et de l'hyperaccumulation de Zn chez A. halleri a été explorée à l’aide d’un croisement intraspécifique entre une population métallicole et une population non métallicole. Une densité élevée de marqueurs SNP a été utilisée pour procéder à l'étape de cartographie QTLNatural habitats are more and more destructed and fragmented by urban expansion and human activities. The fragmentation of natural and agricultural areas by buildings and new infrastructures affects the size, connectivity and the quality of habitats. The populations of organisms inhabiting these anthropized territories are then more isolated. However, differentiation between populations of the same organism depends on demographic and genetic processes such as genetic drift, gene flow, mutation and natural selection. Only species that have developed special tolerance mechanisms can persist under changed environmental conditions. The introduction of contaminants such as metals in the environment may influence plants and animals evolution by modifying the evolutionary forces and thus generating differences between populations. In this work, attention was focused on the genetic consequences of metallic pollution on two species, the earthworm Lumbricus terrestris and the plant model Arabidopsis halleri. Two different approaches have been used to study the genetic response to metallic contamination: a population genetic approach was performed in L. terrestris and a quantitative genetic approach was carried on in A. halleri. First, it was a question of identifying and validating new microsatellite markers in L. terrestris. These markers were then used to characterize the neutral genetic diversity in worms collected from agricultural and urban sites. Secondly, genetic architecture of Zn tolerance and Zn hyperaccumulation was conducted investigated for the first time using an intraspecific crossing between metallicolous and non-metallicolous individuals of A. halleri. High density of SNP markers was used to proceed to the QTL mapping step
4
Johansson, Ambjörn. "Evolution toward pollution-resistant ecotypes of Baltic threespine stickleback, Gasterosteus aculeatus, suggested by AFLP markers." Thesis, Södertörns högskola, Institutionen för livsvetenskaper, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-1935.
Abstract:
This study used amplified fragment length polymorphism (AFLP) to detect changes of genetic variation in threespine stickleback exposed to industrial pollution from pulp- and paper mills along the southern east coast of Sweden. A general loss of allelic diversity was associated with exposure (table 3, linear model, F1,4=7.2 [P=0.055]) and exposed populations also displayed a similar pattern of response (fig 5) despite geographic distance, indicating that evolution toward pollution resistant ecotypes of threespine stickleback is occurring in the Baltic Sea. The result suggests that pollution can be regarded as an agent of directional selection, causing a decrease of evolutionary potential of exposed species in the Baltic Sea.
5
Guan, Jiabao. "Applications of genetic algorithms in groundwater quality management." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/20491.
6
Cullen, Daniel W. "Genetic location and transferability of chromium resistance gene(s) among aquatic bacteria." Thesis, Glasgow Caledonian University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339325.
7
Nowak, Carsten. "Consequences of environmental pollution on genetic diversity in populations of the midge Chironomus riparius." Göttingen Cuvillier, 2008. http://d-nb.info/989862658/04.
8
Veith, Tamie L. "Agricultural BMP Placement for Cost-effective Pollution Control at the Watershed Level." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/27247.
Abstract:
The overall goal of this research was to increase, relative to targeting recommendations, the cost-effectiveness of pollution reduction measures within a watershed. The goal was met through development of an optimization procedure for best management practice (BMP) placement at the watershed level. The procedure combines an optimization component, written in the C++ language, with spatially variable nonpoint source (NPS) prediction and economic analysis components, written in the ArcView geographic information system scripting language. The procedure is modular in design, allowing modifications or enhancements to the components while maintaining the overall theory.
The optimization component uses a genetic algorithm to optimize a lexicographic multi-objective function of pollution reduction and cost increase. The procedure first maximizes pollution reduction to meet a specified goal, or maximum allowable load, and then minimizes cost increase. For the NPS component, a sediment delivery technique was developed and combined with the Universal Soil Loss Equation to predict average annual sediment yield at the watershed outlet. Although this evaluation considered only erosion, the NPS pollutant fitness score allows for evaluation of multiple pollutants, based on prioritization of each pollutant. The economic component considers farm-level public and private costs, accounting for crop productivity levels by soil and for enterprise budgets by field. The economic fitness score assigns higher fitness scores to scenarios in which costs decrease or are distributed more evenly across farms. Additionally, the economic score considers the amounts of cropland, hay, and pasture needed to meet feed and manure/poultry litter spreading requirements.
Application to two watersheds demonstrated that the procedure optimized BMP placement, locating scenarios more cost-effective than a targeting strategy solution. The optimization procedure identified solutions with lower costs than the targeting strategy solution for the same level of pollution reduction. The benefit to cost ratio, including use of the procedure and implementation of resulting solutions, was demonstrated to be greater for the optimization procedure than for the targeting strategy. The optimization procedure identifies multiple near optimal solutions. Additionally, the procedure creates and evaluates scenarios in a repeated fashion without requiring human interaction. Thus, more scenarios can be evaluated than are feasible to evaluate manually.Ph. D.
9
Snyder, Craig David. "Physiological, population, and genetic responses of an aquatic insect (Isonychia bicolor) to chronic mercury pollution." Diss., This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-06062008-165554/.
10
Hum, Stanley. "Detection of latent heritable genetic damage in populations of aquatic snails, Lymnaea stagnalis, exposed in situ to genotoxic pollution." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=30670.
Abstract:
We hypothesized that populations exposed to chronic levels of genotoxins for many generations in situ will accumulate latent heritable genetic damage leading to increases in mutational load and decreased population fitness. Common pulmonate snails (Lymnaea stagnalis) were collected from three sites that differed in pollution level [Manitoulin Island (reference), Beauharnois (moderate pollution), and Varennes (highly polluted)]. These organisms have a rapid generation time and are capable of self-fertilization. Fitness indicators were clutch size, survival (hatching to day 30) and growth (length from hatching to day 90). Recessive deleterious mutations that have accumulated through time are masked as snails preferentially outcrossed, but are expressed when snails self-fertilize. Results obtained by comparing fitness components of snails derived from selfing and outcrossing experiments showed that in sites with higher levels of pollution inbreeding depression increased for clutch size and survival. Results for growth rate were similar to those for clutch size and survival in the two least polluted sites, but not for the most polluted site, due possibly to biased mortality of smaller snails at this site. After correction for size biased mortality, the growth estimates showed patterns similar for the two polluted sites when compared to the reference site. This study suggests that long-term in situ exposure to genotoxic pollution may effect population fitness due to the accumulation of latent heritable genetic damage.
11
Wang, Changgui. "An objective approach to regional wastewater-treatment planning." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310027.
12
Wilson, Alan Elliott. "Cyanobacteria-Grazer Interactions: Consequences of toxicity, morphology, and genetic diversity." Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-04072006-125946/.
Abstract:
Thesis (Ph. D.)--Biology, Georgia Institute of Technology, 2006.Klausmeier, Christopher, Committee Member ; Montoya, Joseph, Committee Member ; Snell, Terry, Committee Member ; Sarnelle, Orlando, Committee Member ; Hay, Mark, Committee Chair.
13
Goktas, Recep Kaya. "Application Of Genetic Algorithms To Calibration And Verification Of Qual2e Model." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605591/index.pdf.
Abstract:
The objective of this study is to develop a calibration and verification tool for the QUAL2E Model by using Genetic Algorithms. In the developed optimization model, an objective function that is formulated on the basis of the sum-of-least squares approach aiming at minimizing the difference between the observed and simulated quantities was used. In order to perform simultaneous calibration and verification, verification of the calibrated results was treated as a constraint and inserted into the objective function as a penalty function.
The performance of the optimization model was tested for different observation data qualities represented by the synthetic perfect and biased data sets. Although it was not possible to obtain the exact values of the kinetic coefficients for any of the tests performed, the coefficient estimates were successful in reflecting the water quality variable profiles in the river.
The results of the tests showed that the performance of the optimization model is generally sensitive to the error in the observed data sets, to the number and location of sampling points, and to the objective function formulation. For the problems that involve multiple water quality variables, a weighting approach used in the objective function formulation resulted in better performances.
The optimization model was also applied for a case study. For the same input data, calibration obtained with the genetic algorithm optimization &ndashsimulation was better compared to the trial-and-error approach.
14
Dixon, Thomas James. "Molecular genetic studies of pollutant response in the European flounder, Platichthys flesus (L.)." Thesis, University of Stirling, 2003. http://hdl.handle.net/1893/57.
Abstract:
Effects of man made pollutants on an ecosystem are initiated at the cellular level where a prime determinant for survival of an organism is its ability to metabolise and excrete toxic chemicals or their metabolites, thereby preventing cellular toxicity or damage to germ cell DNA. Cytochrome P450 (CYP) enzymes are responsible (in concert with the remainder of the Ah battery enzymes) for the metabolism of numerous xenobiotics and endogenous compounds, including the metabolic activation of most environmental toxic chemicals and carcinogens. Genetic polymorphisms which affect performance of these enzymatic detoxification systems may alter tolerance to pollutants and thus survival in polluted environments. Alterations in the susceptibility of individuals and the development of resistant populations has arisen by forced selection of populations with variant genes, resulting in increased detoxification capacity. There is evidence for such scenarios of variations in activities of pollutant biotransforming enzymes of fish contributing to survival in polluted estuarine environments and several chemically resistant populations have been identified in the USA and Europe. In fish it has been demonstrated that CYP1A enzyme activity is required to activate some carcinogenic xenobiotics to a metabolic state in which they can form DNA adducts. The mechanism of reduced CYP1A expression in highly contaminated populations may therefore represent resistance to chemical stressors. European flounder (Platichthys flesus) from some waterways which have a long history of severe sedimentary contamination do not show elevated levels of CYP1A. The aim of the current study was to investigate whether any heritable differences were apparent between offspring from parents inhabiting long-term polluted and pristine areas. Flounder were obtained from a highly polluted estuary in the UK and crossed with fish from a relatively pristine environment. Offspring were raised in communal tanks in order to standardise environmental conditions, and allow investigations into the genetic variation of CYP1A. To allow identification of offspring to parental fish, polymorphic microsatellite loci were isolated and characterised for the flounder. Novel cDNA probes to transcription factors in the detoxification pathway (AhR2 and ARNT2) were cloned for flounder, and RT-PCR / Southern blot methods were developed for quantitation of gene transcript levels. A novel method of CYP1A quantification using real-time PCR was developed. PAH and PCB exposure trials were carried out on mixed batch offspring, and CYP1A gene transcript levels assessed using Northern blot and real-time PCR techniques. Offspring were genotyped to their parents using the microsatellites obtained, and CYP1A transcript levels were correlated with clean and polluted areas. CYP1A was further correlated to transcription factor expression, and data are presented. Following exposure to the commercial PCB mixture, Aroclor 1254, CYP1A transcript levels were found to be significantly lower in families whose parents originated from a polluted area. This observation indicates that there is a possible genetic component to variation in CYP1A levels, and that these fish may have acquired a heritable tolerance to polluted areas. The lack of induction, or correlation with CYP1A levels, of AhR2 and ARNT2 expression indicates a possible AhR independent pathway for the metabolism of PCBs in the flounder. © Tom Dixon 2003 http://www.tomdixon.org
15
Baliardini, Cecilia. "Genetic analysis of cadmium tolerance in Arabidopsis halleri: contribution of CAX1." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/218852.
Abstract:
Analyse génétique de la tolérance au cadmium dans l'espèce Arabidopsis halleri: contribution du CAX1Résumé de la thèseDans les milieux contaminés par les excès en éléments traces métalliques, de rares plantes peuvent accumuler ces éléments a de très fortes concentrations sans symptômes de toxicité. Parmi elles, Arabidopsis halleri, proche parente d' A. thaliana, hyperaccumule le Zn et le Cd. C’est une espèce modèle pour étudier l'homéostasie métallique et l'adaptation aux environnements extrêmes. Alors qu’un ensemble de mécanismes moléculaires permettent d’expliquer l’hyperaccumulation de Zn, la compréhension de la tolérance et de l’accumulation du Cd est bien moins connue. Une analyse de liaison génétique dans A. halleri a permis d'identifier un locus de caractère quantitatif (QTL) majeur co-localisant avec HMA4 et deux autres QTL. HMA4 codant pour une pompe a métaux, impliquée dans la translocation du Cd des racines a la partie aérienne et dans la distribution de ce métal dans les feuilles, a pu être validé par ARN interférence.L'objectif de ce projet est de contribuer a la compréhension de la tolérance au Cd dans A. halleri en identifiant de nouveaux déterminants génétiques.Par cartographie fine, CAX1, codant pour un antiport calcium/proton, a été identifié comme gène candidat pour le second QTL majeur impliqué dans la tolérance au Cd dans A. halleri.Les analyses d’expression de CAX1 dans trois espèces d’Arabidopsis, tolérantes ou sensibles au Cd, et dans la descendance de croisements entre A. halleri et l’espèce sensible A. lyrata, l’étude d’un mutant «knock-out» dans Arabidopsis et des analyses biochimiques ont confirmé l’implication de CAX1 dans la tolérance au cadmium. En séquestrant le calcium dans la vacuole, CAX1 participe a limiter l’accumulation des espèces réactives de l’oxygène (ROS) induite par un excès de Cd et a limiter la toxicité du Cd. Ce rôle est observable lorsque les plantes sont cultivées a basse concentration de calcium. A plus hautes concentrations de calcium, l’expression de CAX1 est induite dans les trois espèces étudiées et ne présente plus de difference entre A. halleri et A. lyrata. En accord avec ce résultat, la detection du locus de caractère quantitatif co-localisant avec CAX1 disparaît lorsque la concentration de calcium augmente dans le milieu. Néanmoins, le rôle de CAX1 dans la tolérance aux stress oxydatifs est observable quelle que soit la concentration en calcium utilisée.L’ensemble des résultats soutiennent un rôle encore inexploré de CAX1 dans les plantes.Doctorat en Sciences
info:eu-repo/semantics/nonPublished
16
Hum, Stanley. "Detection of latent heritable genetic damage in populations of aquatic snails, Lymnaea stagnalis, exposed in situ to genotoxic pollution." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0035/MQ64374.pdf.
17
Mulvaney, Dustin R. "Political ecologies of genetic pollution & containment : social resistance to agricultural biotechnology and the uneven governance of genetically engineered organisms /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2007. http://uclibs.org/PID/11984.
18
Melén, Erik. "Genetic studies on childhood asthma and allergy - role of interactions /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-686-7/.
19
De, Leon Ricardo 1957. "Use of gene probes and an amplification method for the detection of rotaviruses in water." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/191152.
Abstract:
Rotaviruses are one of the most significant causes of diarrheal disease in the world. Their presence in groundwater and drinking water supplies constitutes a health risk to the population. The study of rotaviruses in the environment has been hampered by the lack of accessible and consistent detection methodologies. Gene probes and other molecular techniques are a novel approach for the detection of these viruses in water. The feasibility of these new techniques for the detection and study of rotaviruses in the environment has been assessed using the simian SA-11 and the culturable human Wa rotavirus strains as models. Two general approaches have been undertaken consisting of hybridization of probes with genomic RNA and hybridization with mRNA produced by the virion-incorporated transcriptase. Hybridization of gene probes with genomic dsRNA of rotaviruses in environmental concentrates resulted in the detection of 10 4 immunofoci of Wa rotavirus. In vitro transcription serves as an amplification method with sensitivity 100- to 1000-fold greater than when probing for genomic RNA. The sensitivity obtained in Wa-seeded distilled water and environmental concentrates after in vitro transcription is 2 and 20 immunofoci, respectively. Proteins in environmental concentrates decrease the efficiency of probe hybridization by 10-100 fold. Also, transcriptase-inhibiting factors found in environmental samples decrease the production of mRNA. Both proteins and transcriptase-inhibiting factors can be reduced significantly with Sephadex G-200 columns. Passage of environmental concentrate through Sephadex G-200 spun columns, followed by in vitro transcription, was used to detect rotaviruses in environmental samples. Rotaviruses were detected by this combination of techniques in eight of 20 sewage samples, one of 16 tap water samples, five of 32 ground water samples, and two of nine surface water samples. Only one of 17 samples which tested positive with Wa cDNA 4 was positive for non-specific probe binding. The probing of rotavirus mRNA, amplified by the virion-incorporated transcriptase, is a practical and feasible method for monitoring these viruses in the environment.
20
Yongqiang, Cui. "COST-EFFECTIVE STRATEGY FOR THE INVESTIGATION AND REMEDIATION OF POLLUTED SOIL USING GEOSTATISTICS AND A GENETIC ALGORITHM APPROACH." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215523.
21
White, Paul Andrew. "Detection, discharge and ecological behaviour of genotoxic organic contaminants in the St. Lawrence and Saguenay rivers." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40281.
Abstract:
The goal of this thesis was to examine the sources and ecological behaviour of genotoxic organics in the St. Lawrence river system. A rapid and effective version of the SOS Chromotest was developed to accomplish the task of genotoxicity assessment. The method, validated with standard reference materials, is particularly well suited to complex environmental extracts. The endpoint investigated throughout the thesis, SOS genotoxicity, is empirically related to more familiar endpoints such as mutagenicity and carcinogenicity. Analyses of literature data confirmed correlations between SOS genotoxicity and both Ames/Salmonella mutagenicity and animal carcinogenicity. Analyses of industrial and municipal wastewaters revealed that organic and inorganic chemical production facilities, metal refining and founding facilities and petroleum refineries release high potency wastes. Loading values indicate that low potency sources (e.g. municipal wastewater and pulp & paper facilities) often have exceptionally high loadings. A substantial portion (2.3-99.8%) of industrial genotoxins are associated with suspended particulates. Sorption partition efficients (K$ sb{ rm d-genotox}$) indicate that municipal wastewater and pulp & paper facilities release particularly soluble genotoxins. Extracts of suspended particulate matter collected near industrial discharges are direct-acting. Bottom sediment extracts are less potent and usually require S9 metabolic activation. Genotoxicity of both bottom sediment and suspended particulates are empirically related to the genotoxicity of regional industrial emissions. Direct-acting substances in the water column appear to be less stable and may be converted to more stable pro-genotoxic substances present in the bottom sediments. A mass balance of genotoxicity for St. Lawrence surface waters revealed that domestic, rather than industrial sources make the largest contribution to observed genotoxicity. The importance of domestic wastes was confirmed
22
Larsson, Josefine. "Genetic Aspects of Environmental Disturbances in Marine Ecosystems : Studies of the Blue Mussel in the Baltic Sea." Doctoral thesis, Södertörns högskola, Miljövetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-33697.
Abstract:
Anthropogenic environmental changes can serve as drivers for evolutionary responses in wild populations. To predict the long-term impact of anthropogenic changes on populations, it is crucial to understand the genetic effects caused by these disturbances. The Baltic Sea is considered to be one of the world’s most contaminated seas, and the increase of anthropogenic chemical pollution is a major threat to its ecosystems. This thesis assesses the impact of harbors and sewage treatment plants on physiological traits and genetic structure of resident populations of blue mussels at replicated sites in the Baltic Sea. The initial evaluation of the overall genetic pattern in blue mussel populations in the Swedish West Coast, the Baltic Proper and the Bothnian Sea found genetic differentiation between the three water basins and a low genetic differentiation within each basin, especially within the Baltic Proper. Despite the low genetic differentiation among blue mussels within the Baltic Proper, a parallel genetic differentiation associated with sewage treatment plant effluents was found in this basin. This included genomic regions with a high degree of differentiation between reference sites and sites affected by sewage plants effluent. This genetic differentiation is suggested to be due to post-dispersal selection acting in each generation. In contrast, no parallel genetic differentiation was associated with harbors. We identified five genomic regions in blue mussels, showing strong signs of selection, shared among three out of four replicated reference sites and sites affected by sewage effluents in the Baltic Proper i.e. Askö, Tvärminne and Karlskrona. An initial characterization of these genomic regions revealed functions related to immune and endocrine responses, oxidative stress and shell formation. Our results indicate that selection caused by sewage effluents involves multiple loci. The same genomic regions are found across different locations in the Baltic Proper but there are also unique genomic regions at each location. No genotoxic or histopathological effects were found among blue mussels from sewage effluent-affected areas but a higher frequency of histological abnormalities in the digestive gland were observed in mussels from harbors.Evolutionära anpassningar till miljöstörningar i marina ekosystem: genetisk ekotoxikologi i Östersjön
23
Inostroza, Pedro Verfasser], Henner [Akademischer Betreuer] [Hollert, and Werner [Akademischer Betreuer] Brack. "Organic micropollutants in freshwater ecosystems : pollution dynamic and adverse effects at population genetic level in a model freshwater population / Pedro Inostroza ; Henner Hollert, Werner Brack." Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://d-nb.info/1157122396/34.
24
Inostroza, Pedro [Verfasser], Henner [Akademischer Betreuer] Hollert, and Werner [Akademischer Betreuer] Brack. "Organic micropollutants in freshwater ecosystems : pollution dynamic and adverse effects at population genetic level in a model freshwater population / Pedro Inostroza ; Henner Hollert, Werner Brack." Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://d-nb.info/1157122396/34.
25
Mpherwane, Salome Kedibone. "An investigation into the allozyme genetic variation patterns among populations of freshwater fish from different river systems of Southern Africa." Thesis, University of Limpopo (Turfloop Campus), 2011. http://hdl.handle.net/10386/910.
26
Langevin, Robert. "Genotoxicity in water and sediment extracts from the St. Lawrence river system, using the SOS chromotest." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60498.
Abstract:
Surface water and sediments from the St. Lawrence River system (Quebec region) were analysed for genotoxicity using nonlinear SOS Chromotest parameters, as well as for their chemical concentrations of polycyclic aromatic hydrocarbons and heavy metals. Additionally, sediments chlorobenzenes, polychlorinated biphenyls, organochlorinated pesticides, ammonia and nitrites concentrations were determined. Organic contaminants were extracted dichloromethane. For surface water, fifteen extracts of filtered water and seven of particulates, and for sediments, one extract of pore water and three of particulates proved to be weakly genotoxic. All but one of the genotoxic responses observed in the surface water were obtained from samples taken from the highly industrial portion of the St. Lawrence River system, with the strongest responses observed in Lake St-Louis. Surface water genotoxicants partitioning favors the particulate fraction. Bottom particulates genotoxicity was one thousand fold weaker than suspended particulates. Additionally, whole sediments were extracted with a 10% dimethylsulfoxide-saline solution. Genotoxicity of hydrophilic contaminants was detected in all extracts. The observed distributions of genotoxicity values did not correlate with observed concentrations of demonstrated SOS inducers, mutagens and/or carcinogens, nor with the presence of other toxic chemicals.
27
Castro, Giner Francesc. "Genetic and environmental factors in asthma: a population based European study." Doctoral thesis, Universitat Pompeu Fabra, 2009. http://hdl.handle.net/10803/7194.
Abstract:
L'asma és una malaltia d'etiologia complexa, formada per factors genètics i ambientals, on la interrelació de ambdós factors mitjançant interaccions gen-ambient juga un paper clau. L'objectiu d'aquesta tesi ha sigut aprofundir en el coneixement del paper dels polimorfismes genètics, i la seva interacció amb factors ambientals, en la ocurrència d'asma, atòpia i hiperreactivitat bronquial. Aquest objectiu ha estat desenvolupat a través de la replicació de variants genètiques prèviament identificades, l'avaluació d'interaccions gen-ambient i la identificació de nous gens de susceptibilitat mitjançant un disseny basat en el genotipatge de variants genètiques all llarg del genoma en pools d'ADN. La tesi ha estat majoritàriament duta a terme dins l'estudi European Community Respiratory Health Survey (ECRHS) que està comprès per 5.000 individus seguits durant 9 anys, pels quals es disposa d'un qüestionari complet sobre símptomes respiratoris, avaluacions clíniques, informació sobre exposicions ambientals i mostres de ADN. Aquesta tesi a replicat l'associació del polimorfismes dels gens TNFA i NPSR1 amb asma. A més s'han establert les interaccions entre TNFA i obesitat, NQO1 i contaminació atmosfèrica, i NPSR1 i edat d'inici d'asma. L'anàlisi de pools d' ADN ha permès associar la regió on es situa el gen SGK493 amb atòpia. Aquesta tesi contribueix al coneixement de l'etiologia d'asma amb la identificació i replicació d'associacions genètiques i interaccions gen-ambient.Asthma is a disease with a complex etiology, involving multiple genetic and environmental factors, and with an important role of the interplay of these factors through gene-environment interactions. In this thesis I aimed to advance our knowledge on the importance of genetic polymorphisms and their interaction with environmental data for the occurrence of asthma and related phenotypes (atopy and bronchial hyperreactivity). This objective was developed through the replication of genetic associations previously reported, the assessment of gene-environment interactions and the identification of new susceptibility genes using genome-wide analysis based on a pooling DNA strategy. The thesis was, mostly, performed within the European Community Respiratory Health Survey (ECRHS). This cohort has information and DNA samples from approximately 5,000 adult subjects followed-up for 9 years, with extensive questionnaires on respiratory symptoms, clinical evaluations and information on environmental exposures. This thesis replicates previous effects on asthma of polymorphisms in TNFA and NPSR1 genes. In addition, interactions have been established between TNFA and obesity, NQO1 and air-pollution, and NPSR1 and age at onset of asthma. The approach based on genome-wide analysis of DNA pools identified the SGK493 region being associated with atopy. This thesis contributes to the understanding of the etiology of asthma through the identification and replication of genetic associations and gene-environment interactions.
28
Pazúriková, Jana. "Adaptivní model pro simulaci znečištění ovzduší." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2012. http://www.nusl.cz/ntk/nusl-236487.
Abstract:
Air pollution harms the environment and human welfare. Computer models and their simulation are useful tools for deeper understanding of processes behind as they quite accurately represent the dispersion and transformation of pollutants with advection diffusion equation or by other concepts. Current models give valid results only to constrained cases of initial conditions. The general model combining the several specific models which is able to change according to input parametres and improve with training is proposed. The adaptiveness of the system is provided by decision tree as data structure with information for selection and combination process and genetic algorithm as optimization method for adjusting the tree. The evaluation of implemented system proves that the combination of models gives better results than models themselves. Even with simple specific models, the system has achieved results comparable to state-of-art models of air pollution.
29
Buma, Eni Liudmiliza Leite. "Identificação e distinção de fonte de poluição fecal na Bacia Hidrográfica Ribeirão João Leite por metodologias moleculares." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/7039.
Abstract:
Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-03-29T20:09:57Z
No. of bitstreams: 2
Dissertação - Eni Liudmiliza Leite Buma - 2017.pdf: 1928297 bytes, checksum: 00dfb2987c7dc920fba208a5861948fe (MD5)
license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-03-31T10:28:49Z (GMT) No. of bitstreams: 2 Dissertação - Eni Liudmiliza Leite Buma - 2017.pdf: 1928297 bytes, checksum: 00dfb2987c7dc920fba208a5861948fe (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Made available in DSpace on 2017-03-31T10:28:49Z (GMT). No. of bitstreams: 2 Dissertação - Eni Liudmiliza Leite Buma - 2017.pdf: 1928297 bytes, checksum: 00dfb2987c7dc920fba208a5861948fe (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-07
Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Water courses that pass through areas of production, whether agricultural, pasture or housing, are subject to discharge of municipal and industrial sewage systems. These waters can be directed to river basins and redistributed to networks of water treatment and public supply. Normally, surface raw water has high concentrations of total coliforms, thermotolerant coliforms and E. coli. However, the microbiological indicator of fecal contamination, E. coli, does not present specificity, limiting, therefore, the host identification causing fecal pollution in water stream. As an alternative, bacteria of the genus Bacteroides have been suggested as potential alternative indicators of fecal pollution. Bacteroides are strictly anaerobic, exclusive and specific to the human gastrointestinal tract, and are also present in homeothermic animals. Because its inability to withstand aerobic environments, Bacteroides are considered as promising indicators of recent fecal pollution. Their identification in water bodies is usually performed by the presence of the 16S rRNA genetic marker of the order Bacteroidales. The objective of this study was to evaluate the microbiological and physico-chemical quality of the water of the Ribeirão João Leite Basin, responsible to supply 50% of water to the city of Goiânia, as well as the evaluation of the 16S rRNA Bacteroidales marker as an indicator of human and / or animal fecal pollution in waters of this basin. For this purpose, 91 samples of surface freshwater were collected from 13 points located along the Ribeirão João Leite Hydrographic Basin extension. Also, human and animal fecal samples were collected to test the sensitivity and specificity of primers to trace the 16S rRNA Bacteroidales marker. Based on the CONAMA Resolution 357/2005 Class II for fresh water, 5.5% (5/91) of the samples had a turbidity level above > 100 NTU (119-180 NTU), while 33% presented values below <103 CFU / 100 mL for thermotolerant E. coli. The mean values were found to be between 1.24 x 103-5.03 x 104 CFU / 100 mL. The 16S rRNA Bacteroidales ruminant host marker was identified in points with high agricultural and cattle influence, on the other hand, the presence of the 16S rRNA Bacteroidales marker as an indicator of human fecal pollution was not detected in the 5 analyzed points. The results obtained will be able to collaborate with sanitary measures to reduce the level of turbidity and also to identify the source of the fecal contamination in these bodies of water, thus minimizing the risk of dissemination of waterborne diseases.
Cursos de água que atravessam áreas de produção, sejam elas agrícolas, de pastagens ou habitacional, estão sujeitos à captação de sistemas de esgoto municipais e industriais. Essas águas podem ser direcionadas a bacias hidrográficas e redistribuídas a redes de estação de tratamento de água e abastecimento público. Normalmente, águas de mananciais apresentam elevados níveis de concentrações de coliformes totais, coliformes termotolerantes e E. coli. Entretanto, o indicador microbiológico de poluição fecal E. coli, não apresenta especificidade, limitando, portanto, a identificação do hospedeiro causador da poluição fecal em determinada corrente de água. Como alternativa, as bactérias do gênero Bacteroides vêm sendo sugeridas como potenciais indicadores alternativos de poluição fecal. Bacteroides são estritamente anaeróbicas, exclusivas e específicas ao trato gastrointestinal humano, apresentando especificidade a animais homeotérmicos. Por serem incapazes de resistir a ambientes aeróbios são consideradas como promissores indicadores de poluição fecal recente. A sua identificação em corpos de água é geralmente realizada pela presença do marcador genético 16S rRNA da ordem Bacteroidales. Este estudo teve como objetivos avaliar a qualidade microbiológica e físico-química da água bruta superficial da Bacia Hidrográfica do Ribeirão João Leite, responsável por 50% de abastecimento da cidade de Goiânia, e também, a avaliação do marcador 16S rRNA Bacteroidales como indicador da fonte de poluição fecal humana e/ou animal em águas desta bacia. Para tal, foram coletadas 91 amostras de água bruta superficial de 13 pontos localizados ao longo da extensão da Bacia Hidrográfica do Ribeirão João Leite, assim como, amostras de matéria fecal humana e animal de modo a testar a sensibilidade e especificidade de oligonucleotídeos iniciadores para o rastreamento do marcador 16S rRNA Bacteroidales. Baseado na Resolução CONAMA 357/2005 Classe II para águas doces, 5,5% (5/91) das amostras apresentaram nível de turbidez acima de >100 NTU (119-180 NTU), enquanto que 33% apresentaram valores inferiores a <103 CFU/100 mL para E. coli termotolerante, sendo os valores médios encontrados entre 1,24 x 103–5,03 x 104 CFU/100 mL. O marcador 16S rRNA Bacteroidales hospedeiro bovino (ruminante) foi identificado em água bruta superficial dos pontos coletados com alta influência agropecuária, em contrapartida, dos 5 pontos analisados não foi detectado a presença do marcador 16S rRNA Bacteroidales como indicador de poluição fecal humana. Os resultados obtidos poderão colaborar com medidas sanitárias que visam a redução do nível da turbidez e na identificação da origem da contaminação microbiológica fecal nesses corpos d’água minimizando, desta forma, o risco de disseminação das doenças de veiculação hídrica
30
Gough, Kerry. "Alien receptions : boundary contagion, generic pollution and Ripley as a shifting cultural signifier." Thesis, University of Nottingham, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.523059.
31
Pearce, Richard John. "A generic approach to the assessment of cross-media pollution within catchment scale landscapes." Thesis, Cranfield University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401678.
32
Monthe, Luc Arthur. "Etude des équations aux dérivées partielles hyperboliques application aux équations de Saint-Venant." Rouen, 1997. http://www.theses.fr/1997ROUES074.
Abstract:
Dans ce travail, nous avons adapté une méthode de volumes finis aux équations de Saint-Venant avec termes sources, dans des configurations monodimensionnelles et bidimensionnelles complexes. Ces équations représentent les écoulements de l'eau peu profonde, consécutifs par exemple a une rupture de barrage. Pour la partie hyperbolique des équations, le schéma de Roe, solveur approché de Riemann, est introduit, et amélioré par une modification entropique, afin de prendre en compte les configurations particulières, telles que l'écoulement sur fond sec. Une extension à l'ordre deux de ce schéma a été réalisée, soit par la méthode de limitation de flux, soit par la méthode MUSCL en espace et Runge-Kutta 2 en temps. Une analyse de stabilité numérique non linéaire a été menée ; cela a permis la justification et la prédiction de limitations sur la condition CFL, confirmées par les expériences numériques. D'autre part, on introduit un schéma fractionné pour la prise en compte du terme source. La stabilité et la convergence du schéma vers la solution entropique sont prouvées dans le cas scalaire. Dans le cas de problèmes bidimensionnels, et afin de traiter correctement les termes de diffusion, des schémas conçus et analysés récemment ont été appliqués. Il s'agit d'un schéma à neuf points (VF9) dans le cas de maillages structurés, et d'un schéma à quatre points (VF4) dans le cas de maillages non structurés. En outre, une technique d'adaptation de maillage basée sur la méthode des ressorts a été utilisée avec succès, dans le cas de maillages structurés, afin de capturer avec plus de précisions les ondes de chocs et de détente. Enfin, on présente une méthode originale d'optimisation, les algorithmes génétiques (GAS), faisant le lien entre la méthode des volumes finis introduite et l'identification de paramètres physiques. Les expériences numériques réalisées, entre autres pour la propagation de polluants dans des domaines à géométrie complexe, ont confirmé les performances de ces méthodes.
33
Carissan-Lloyd, Florence Marie Milka. "Seasonal variations in aspects of Mytilus edulis L. immune function and allozyme genetics in relation to pollution." Thesis, Bangor University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312406.
34
Shen, Pingping, and 沈萍萍. "Benthic infaunal community at an intertidal mudflat and molecular analysis of the dominant species Neanthes glandicincta (Polychaeta)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40887996.
35
Renault, Sophie. "Etude écotoxicologique des impacts des contaminations métalliques et organiques chez l'anguille européenne (Anguilla anguilla L.), dans l’estuaire de la Gironde." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14923/document.
Abstract:
Depuis plusieurs dizaines d’années, la population des anguilles européennes a souffert d’un dramatique déclin et est classée parmi les espèces hors de leurs limites biologiques depuis 1998. Différents phénomènes, tels que la pêche, les obstacles aux migrations, ou le réchauffement climatique, en sont à l’origine. Cependant, les perturbations environnementales, telles que les contaminations métalliques et organiques ou les épisodes d’hypoxie, participent probablement à la vulnérabilité de cette espèce. Or, l’estuaire de la Gironde est soumis à des contaminations poly-métalliques historiques, ainsi qu’à des contaminations organiques de différentes origines, et à des épisodes hypoxiques réguliers. Les travaux menés au cours de cette thèse, se sont donc composés d’études de terrain visant à identifier les contaminants majeurs chez les anguilles jaunes de l’estuaire de la Gironde, ainsi que leur voie de bio-accumulation et leurs impacts au niveau physiologique, biochimique et moléculaire. Ces études ont nécessité la mise en place d’expériences préliminaires ayant pour objectifs de vérifier les impacts de certaines procédures, telles que l’anesthésie et la mise en cage des anguilles jaunes. D’autre part, les impacts des deux principaux contaminants métalliques et organiques des anguilles européennes de l’estuaire de la Gironde, ont été testés, de façon individuelle et combinée, ainsi que ceux de l'hypoxie sur des anguilles pré-contaminées ou non, lors d’une étude expérimentale.Ainsi, ces travaux ont mis en évidence que les anguilles européennes installées dans la zone avale de l’estuaire, étaient susceptibles d’être soumises à des contaminations poly-métalliques plus importantes, essentiellement d’origine trophique, responsables d’une croissance pondérale moins élevée et de perturbations transcriptionnelles hépatiques et cérébrales. De plus, bien que les contaminations métalliques de ces anguilles ne mettent pas ne danger la santé humaine, les contaminations en PCB sont, en revanche, supérieures aux normes de consommation. D’autre part, ces travaux ont également mis en évidence des dérèglements mitochondriaux ainsi qu’un stress oxydant, au niveau branchial et cérébral chez des anguilles contaminées au Cd, et au niveau cérébral, branchial, hépatique et rénal chez les anguilles contaminées aux PCB. Enfin, la concomitance de ces deux contaminants et/ou d’un épisode d’hypoxie, réduit et/ou retarde les capacités de réponses transcriptionnelles de ces anguilles. Il semble donc que les différentes perturbations chimiques subies par les anguilles européennes au stade jaune au sein de l’estuaire de la Gironde participent de façon non négligeable à la vulnérabilité de cette espèceFor several decades, the European eel has been suffering from a dramatic decline and has been classified among species beyond their biological limit since 1998. Different phenomena, as fishing, migration barriers, or global warming, are to blame. Environmental perturbations, as metallic and organic contaminations, or hypoxic episodes, probably take part to the vulnerability of this species. The Gironde estuary has been submitted to historic poly-metallic contaminations, to organic contaminations from different origins, and to regular hypoxic episodes. This thesis work is composed of field studies aimed to identify the main contaminants in yellow eel living in the Gironde estuary, their major bioaccumulation way and impacts on physiological, biochemical and molecular parameters. These studies needed preliminary experiments aimed to verify whether some field and handling procedures are consistent with ecotoxicological analyses. Moreover, impacts of the two main contaminants in European eels from the Gironde estuary have been assessed individually or combined, with those of hypoxia on pre-contaminated eels.Thus, these studies have demonstrated that European eels installed in the downstream area of the estuary, were likely to be subject to largest poly-metallic contaminations, mostly by food web, and responsible for a less weight gain and high liver and brain transcriptional disturbances. Furthermore, although the metal contamination of eels does not endanger human health, PCB contaminations are higher than consumption standards. On the other hand, these studies have also revealed oxidative stress and mitochondrial disorders in gills and brain of Cd-contaminated eels, and in brain, gills, liver and kidneys of PCB-contaminated eels. The combination of these two contaminants and/or an episode of hypoxia, reduces and/or delays the transcriptional responses ability of these eels. It seems that the different chemical disturbances, suffered by the yellow eels in the estuary of the Gironde, participate significantly to this species vulnerability
36
Rodrigues, Dayane Sereno Baêta. "Poluentes marinhos como fatores de estresse em esponjas e mexilhões." Universidade do Estado do Rio de Janeiro, 2011. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=3522.
Abstract:
A biota marinha está exposta a uma elevada quantidade de substâncias
tóxicas que podem causar graves problemas ao ambiente. As esponjas (Porifera) e
os mexilhões (Mollusca) por serem sésseis e filtradores são utilizados como
bioindicadores de poluição. A experimentação com aquários permite a realização de
ensaios controlados, acompanhamento da resposta a diversos poluentes,
concentrações e tempo de exposição. Os objetivos deste estudo foram: I). avaliar a
imunocompetência através da expressão de proteínas do sistema imune Fator
Inflamatório de Enxerto AIF -1 e pP38 por teste de ELISA (do inglês, Enzyme Linked
Immuno Sorbent Assay) em esponjas expostas a poluentes, II) acompanhar a
expressão das proteínas AIF-1 e pP38 nas cinco espécies de esponjas marinhas:
Aplysina fulva (Pallas, 1766), Chondrilla aff. nucula Schimidt, 1862, Dysidea robusta
Vilanova e Muricy 2001, Polymastia janeirensis (Boury-Esnault, 1973) e
Hymeniacidon heliophila (Parker, 1910) após exposição a lipopolisacarídeo (LPS) de
E. Coli III) avaliar a expressão das proteínas AIF-1 e pP38 nas espécies C. aff.
nucula e P. janeirensis após exposição a dodecil sulfato de sódio (SDS) IV) avaliar a
mortalidade de mexilhões quando expostos ao dispersante Triton X-100 e esgoto
doméstico in natura. Os resultados indicam que as esponjas A. fulva, C. aff. nucula,
D. robusta e P. janeirensis expostas a 20 μg/mL de LPS por 30 minutos, uma, três,
24 e 48 horas apresentaram aumento de expressão da proteína AIF-1 em relação ao
controle, com diferentes tempos de resposta para cada espécie. A esponja H.
heliophila exposta a 30 μg/mL de LPS apresentou diferença significativa na
expressão de AIF-1 em relação ao controle na exposição por 30 min, uma, quatro,
24 e 48 horas. Contudo, não houve diferença significativa na expressão de outra
proteína, a quinase pP38, nesses ensaios. As esponjas C. aff. nucula e P.
janeirensis foram expostas a 0,25 mg/L de dodecil sulfato de sódio (SDS) por 24 e
48 horas. C. aff. nucula apresentou aumento da expressão de AIF -1 quando
comparada ao controle em 24 e 48 horas, mas para P. janeirensis não houve
diferença significativa. Os mexilhões Perna perna foram expostos a poluentes de
duas maneiras a detergente Triton X-100 0,10 g/L por três, seis, 12 e 18 horas que
induziu diferença significativa na mortalidade em seis, 12 e 18 horas em comparação
com o controle e a a esgoto doméstico in natura diluído na proporção de 1:50 não
houve mortalidade no tratamento ou no controle. A variação da expressão da
proteína AIF-1 observada nas cinco espécies de esponjas marinhas confirma a
utilização dessa proteína como eficiente biomarcador de estresse. Os mexilhões
foram bons bioindicadores da poluição por detergente.Marine biota is constantly exposed to several toxic substances which may cause severe environmental problems. Sponges (Porifera) and mussels (Mollusca) are often used as pollution bioindicators mainly due to their sessile and filter feeding habits. Laboratory experiments using aquaria enable the performance of controlled assays, following the various responses of animals to different concentrations and types of pollutants, besides of exposure time. The aims of this study were: I) evaluate the immunocompetence using proteins of the immune system Allograph Inflammatory Factor (AIF-1) and Pp38 by ELISA Enzyme Linked Immuno Sorbent Assay in sponges exposure to pollutants II) evaluate the expression of AIF-1 and pP38 at the five species of marine sponges Aplysina fulva (Pallas, 1766), Chondrilla aff. nucula Schimidt, 1862, Dysidea robusta Vilanova e Muricy 2001, Polymastia janeirensis (Boury-Esnault, 1973) e Hymeniacidon heliophila (Parker, 1910) after exposure to Escherichia coli lipopolysaccharide (LPS) III) evaluate the expression of AIF-1 and pP38 in C. aff. nucula and P. janeirensis after exposure to sodium dodecyl sulfate (SDS) IV) evaluate the mortality of mussel Perna perna after exposed to detergent Triton X-100 and domestic sewage The results indicate that A. fulva, C. aff. nucula, D. robusta and P.janeirensis sponges exposed to 20 μg/mL of E. coli LPS during 30 minutes, one, three, 24 and 48 hours presented an increase in AIF-1 expression when compared to controls, at different response times for each species. The sponge H. heliophila exposed to 30 μg/mL of LPS presented a significant difference in the expression of AIF-1 compared to control, in short (30 min, one four hours) and long (24 and 48 hours) time exposure assays, but there were no significant difference in the expression of pP38 protein in any of the assays. Sponges C. aff. nucula and P. janeirensis were exposed to 0.25 mg/L of sodium dodecyl sulfate (SDS) for 24 and 48 hours. C aff. nucula showed increased expression of AIF-1 when compared to the control at 24 and 48 hours. For P. janeirensis there were no significant difference between treatments and controls. Perna perna mussels were exposed to pollutants in two assays. The animals were exposed to the detergent Triton X-100 0.10 g/L for three, six, 12 and 18 hours. There were significant differences in mortality in six, 12 and 18 hours. The mussels were also exposed to domestic sewage diluted in 1:50 proportion. This assay did not induce mortality in the treatment and control. The variation in the expression of AIF-1 protein observed in five species of the marine sponges confirms the efficient use of this protein as a stress biomarker. It was demonstrated that mussels are good bioindicators of detergent pollution.
37
Dutilleul, Morgan. "Réponses microévolutives et coûts adaptatifs de populations de Caenorhabditis elegans exposées à des stress environnementaux." Thèse, Montpellier 1, 2013. http://www.archipel.uqam.ca/5860/1/D2565.pdf.
Abstract:
Dans l'environnement, l'évolution contemporaine des organismes vivants est de plus en plus dépendante des perturbations d'origine anthropique. En particulier, la pollution amplifie l'intensité ou la quantité des pressions de sélection auxquelles sont soumises les populations. Or ces changements peuvent avoir des effets négatifs sur la vie, la reproduction et la croissance des individus. La démographie des populations peut aussi être affectée, tout comme au cours des générations, les caractéristiques phénotypiques et génétiques de ces populations. Ainsi en réponse aux pressions de sélection, des changements microévolutifs sont susceptibles de se manifester. Mais ces phénomènes entraînent en parallèle la mise en place de coûts adaptatifs. Par exemple, une réduction de la diversité génétique d'une population induit une diminution du potentiel adaptatif face à d'autres contraintes. Ceci peut fragiliser le maintien de populations vivant dans des environnements toujours plus changeants, notamment avec l'accroissement des activités humaines. Dans une démarche d'évaluation des risques écologiques, il ne suffit donc plus d'étudier les mécanismes d'action et les effets néfastes immédiats des polluants sur les organismes vivants. Il est également nécessaire de développer nos connaissances sur l'évolution des populations en milieu pollué, et plus globalement en milieu stressant. Dans ce contexte, cette étude vise à déterminer les réponses microévolutives de populations d'un organisme modèle, Caenorhabditis elegans, exposées à des stress environnementaux et à mesurer les coûts adaptatifs de ces microévolutions. Ces populations ont été exposées expérimentalement, durant 22 générations, à une forte concentration en uranium, en chlorure de sodium ou à une alternance de ces deux polluants. L'analyse des modifications phénotypiques et génétiques observées, au travers des mesures de traits d'histoire de vie, a été accomplie grâce à plusieurs techniques de génétique quantitative. Nous avons notamment mis en évidence une différentiation génétique des populations exposées, associée à augmentation de la résistance, au cours du temps. La vitesse des réponses évolutives était dépendante des conditions d'exposition et de leurs effets sur l'expression de la structure génétique des traits (matrice G). Ces phénomènes microévolutifs ont pu être reliés à des coûts adaptatifs, tels qu'une réduction de la fertilité, dans de nouveaux environnements stressants (ex : augmentation de la température) ou en l'absence de stress. Ainsi, même après plusieurs générations sans la présence de polluant, les populations adaptées voient leur fragilité augmenter par rapport à des populations non adaptées. Toutefois, nous n'avons pas identifié de coûts supplémentaires pour les populations adaptées à l'environnement d'alternance par rapport à celles adaptées à une pollution constante. Ce projet nous a permis de mieux identifier comment une exposition à un ou deux polluants peut affecter la réponse évolutive de populations de C. elegans et d'évaluer les conséquences sur leur sensibilité aux conditions environnementales.
______________________________________________________________________________
MOTS-CLÉS DE L’AUTEUR : évolution expérimentale, génétique quantitative, coûts adaptatifs, stress environnementaux, traits d'histoire de vie, structure génétique, adaptation locale, évolution du généralisme, Caenorhabditis elegans, pollution, uranium
38
Chivers, Alicia M. "Investigating the Effects of 17α-Ethynylestradiol on Mitochondrial Genome Stability." PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/2989.
Abstract:
Environmental toxicants are ubiquitous throughout the environment as a result of human activity. Among these toxicants, environmental estrogens are a category of particular concern due to their environmental prevalence and potency in altering reproductive traits. While many studies have addressed the detrimental effects of environmental estrogens on both aquatic and terrestrial organisms, few have analyzed the potential for these compounds to alter mitochondrial function. Mitochondria are the primary energy-generating system for all eukaryotic life, supporting all aspects of development, metabolism, and growth. Each cell within the body contains many mitochondria which in turn contain multiple copies of their own DNA genome, mitochondrial DNA (mtDNA). Mutations in mtDNA are responsible for a wide range of human diseases such as metabolic syndromes, cancers, and obesity. Among these mitochondrial diseases many are characterized by increased levels of heteroplasmy, multiple mitochondrial DNA haplotypes within an individual. Increased heteroplasmy can alter normal mitochondrial function and influence disease initiation and progression.
To date, no studies have investigated the effects of synthetic estrogens on mitochondrial genome stability. Synthetic estrogens have the capacity to bind to estrogen receptors and initiate estrogenic responses through translocation into the mitochondrion. Despite our knowledge about the relationship of heteroplasmy and disease, we still do not have a complete grasp of the mechanisms of heteroplasmic induction. Here we report our analysis of the effects of 17α-ethynylestradiol (EE2) exposure in three studies to investigate its effect on mitochondrial genome stability. Data analysis reveals a statistically significant relationship between EE2 exposure and increased heteroplasmic frequency.
39
Minot, Marceau. "Traits biologiques et facteurs environnementaux structurant les mouvements locaux et la dispersion des libellules( Insecta, Odonata) dans les réseaux de mares. Pond creation and restoration:: patterns of odonate colonisation and community dynamics Biometry of the large dragonfly Anax imperator (Odonata, Aeshnidae):: A study of traits from larval development to adults Effects of water pollution on the larval development and condition of the adults at emergence in Aeshna cyanea (Odonata: Aeshnidae) Habitat use and movements of a large dragonfly (Odonata: Anax imperator) in a pond network. Diversity and genetic structure of Anax imperator populations at the European scale." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMR031.
Abstract:
Au cours des dernières décennies, le nombre de mares a connu un déclin de plus de 50 % dans les pays européens, atteignant parfois jusqu'à 90 % dans certaines régions. Cette diminution a entraîné une forte perte de connectivité entre les mares. Pourtant, ces écosystèmes petits et dispersés sont essentiels au cycle de vie d'une grande diversité d'espèces d'eau douce. Les politiques d'aménagement du territoire, comme la création des Trames Vertes et Bleues en France, visent à améliorer les continuités écologiques pour permettre le maintien des populations existantes et les échanges entre elles. Cependant, les études de connectivité entre les mares doivent prendre en compte les capacités de dispersion des espèces et cette information fait souvent défaut pour orienter les mesures de restauration. Dans le présent travail, nous avons étudié les capacités de dispersion des libellules à plusieurs échelles spatiales ainsi que les caractéristiques biologiques et les facteurs environnementaux qui façonnent leurs mouvements. Dans la première partie, nous avons évalué la colonisation par les libellules de 20 mares normandes pendant les trois années suivant leur création ou leur restauration. Les résultats mettent en évidence des taux de colonisation élevés pendant la première année et aucune différence de richesse spécifique n'a été constatée entre les mares nouvellement créées ou restaurées. Cela suggère que la restauration des mares après un assèchement total ne devrait pas toujours être prioritaire par rapport à la création de nouvelles mares dans les stratégies de gestion. Nous avons constaté que les espèces généralistes étaient davantage présentes la première année après la création ou la restauration des mares, alors que la présence d’espèces spécialistes des forêts augmentait avec l'âge du plan d’eau. Les résultats ont également mis en évidence que le contexte paysager autour des mares (i.e. milieu forestier ou ouvert) avait un effet sur la composition des communautés de libellules. Enfin, l'abondance totale des espèces d'odonates était liée à la densité des plans d’eau alentours. Ce résultat souligne que les mares très connectées peuvent abriter des populations plus importantes que les mares isolées et donc être plus résistantes aux perturbations. La deuxième partie fournit des éléments sur le développement larvaire d'Anax imperator et la relation entre les caractéristiques morphologiques des larves et des adultes. Les résultats suggèrent que la survie de cette espèce pendant la période de maturation pourrait dépendre de la longueur des individus. Nous avons également essayé d'étudier la dispersion natale en marquant 87 individus à l'émergence, mais seuls deux mâles ont été retrouvés après la période de maturation. Enfin, l'effet de deux polluants de l'eau (Round-up et DEET) sur le développement larvaire et les adultes d'Aeshna cyanea a également été étudié à différentes concentrations. Les larves ont été élevées dans des conditions de laboratoire et exposées à des concentrations allant jusqu'à 30 mg.L-1 des deux polluants. Aucun effet des polluants sur les conditions morphologiques des larves ou des ténéraux n'a été détecté, ce qui suggère que A. cyanea est une espèce tolérante aux potentielles pollutions de l'eau dans les mares. Le niveau de la protéine de stress HSP70 était également similaire selon les différents traitements, mais les adultes ténéraux présentaient des niveaux de stress plus élevés que les larves, ce qui suggère que l'émergence a provoqué un stress élevé chez les individusDuring the last decades, the number of ponds decreased by more than 50 % in European countries, occasionally reaching up to 90 % in some regions. Their decline in number has led to a strong loss of connectivity between waterbodies. Yet, these small and scattered ecosystems are essential for the life cycle of a high diversity of freshwater species. Land use policies like the creation of Greenways and Blueways in France aim to improve ecological continuities to allow maintenance of existent biological populations and exchanges between them. However, the connectivity between ponds must be considered according to the dispersal abilities of freshwater species and this information often lacks to guide restoration measures. In the present work, we studied the dispersal abilities of dragonflies on several spatial scales and investigated the biological traits and environmental factors that shaped their movements. In the first part, we evaluated the colonization of 20 ponds in Normandy by dragonflies during three years after pond restoration or pond creation. The results highlight high colonization rates during the first year and no difference in species richness was found between newly created or restored ponds. This suggests that restoration of ponds after complete drought should not always be prioritized over pond creation in management strategies. We found that generalist species were more present in the first year after pond creation or restoration, whereas the occurrence of forest specialists increased with the age of the pond. The results also highlighted that the landscape context around ponds (i.e. forest vs. open lands) had an effect on the composition of dragonfly communities. Finally, the total abundance of odonate species was related to the density of other ponds in the surroundings. This result emphasizes that highly connected ponds can support larger populations than isolated ones and thus, be more resilient to perturbations. The second part provides insights into the larval development of Anax imperator and the relationship between morphological traits of larvae and adults. The results suggest that the survival of this species might depend on its body length during the maturation period. We also tried to study the natal dispersal by marking 87 individuals at emergence, but only two males were resighted after the maturation period. Finally, the effect of two water pollutants (i.e. Round-up and DEET) at different concentrations was also investigated on the larval development and adults of Aeshna cyanea. Larvae were reared under laboratory conditions and exposed to concentrations up to 30 mg.L-1 of the two pollutants. No effect of the pollutants was detected on the morphological conditions of larvae or tenerals, suggesting that A. cyanea is tolerant to potential water pollution of ponds. The level of HSP70 stress protein was also similar according to the different treatments, but teneral adults presented higher levels of stress than larvae, suggesting that emergence induced a high stress in the individuals. The third part focuses on the dispersal of A. imperator. We first assessed the local movements within a pond network in the Normandy region
40
Lindgren, Torsten. "Cabin Air Quality in Commercial Aircraft : Exposure, Symptoms and Signs." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3462.
41
Engvall, Karin. "A Sociological Approach to Indoor Environment in Dwellings : Risk factors for Sick Building Syndrome (SBS) and Discomfort." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3506.
42
Serra, Anne-Antonella. "Réponses écophysiologiques et moléculaires des plantes aux stress xénobiotiques complexes de faible intensité : implications dans les capacités de protection environnementale des bandes enherbées." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S005/document.
Abstract:
Les pollutions par les xénobiotiques, en particulier les pesticides, et les métaux lourds issus des activités agricoles présentent une grande complexité de composition chimique et de dynamique spatio-temporelle. La présence de bandes enherbées entre les parcelles cultivées et les cours d’eau permet une limitation de la diffusion de ces pollutions résiduelles vers les milieux naturels. Le compartiment végétal de ces bandes enherbées peut jouer de multiples rôles dans ce contexte de protection environnementale. L’étude comparative réalisée in situ et en conditions contrôlées de laboratoire a permis de mettre en évidence le rôle biologique du compartiment végétal avec son implication directe dans les processus in planta d’absorption, de stockage et/ou de dégradation au moins partielle. Un tel rôle phytoremédiateur est dépendant de la capacité des plantes à se maintenir sur ces milieux pollués, qui diffère selon l’espèce considérée et structure ainsi les communautés végétales des bandes enherbées. L’étude intégrative en conditions contrôlées des réponses des plantes aux interactions avec les xénobiotiques à faibles doses, à différentes échelles de complexité du fonctionnement végétal, a permis de montrer les effets de ces stress chimiques chez l’espèce modèle Arabidopsis thaliana et chez l’espèce prairiale Lolium perenne. Les xénobiotiques et les métaux lourds à des doses subtoxiques ont induit d’importants bouleversements métabolomiques et moléculaires chez ces espèces, avec des effets cryptiques de ces polluants et de leurs produits de dégradation. L’analyse en conditions de multi-pollution, qui reflètent de manière réaliste les pollutions péri-agricoles, a montré la complexité et la difficulté de prédiction des interactions entre les effets des contaminants en mélange. Ces mécanismes de réponses diffèrent selon l’espèce et le polluant et laissent supposer des divergences en termes de perception et/ou de transport des polluants, ou de coordination des réponses moléculaires et métaboliques. Arabidopsis a ainsi présenté une coordination de ses réponses orientée vers une augmentation des métabolites de stress, et une diminution des métabolites carbonés (sucres solubles), en parallèle de modifications de l’expression de gènes impliqués dans les défenses antioxydantes, les défenses contre les stress xénobiotiques, ou dans la dynamique des phytohormones. Le stress chimique a entraîné chez Lolium des modifications majeures du métabolisme azoté, ainsi qu’un remaniement des processus de photorespiration. L’analyse transcriptomique de cette espèce a de plus montré que la majorité des gènes identifiés sont impliqués dans des voies de transduction de signal, montrant ainsi la complexité des mécanismes de réponse et les couplages qui existent entre les signaux métaboliques, en particulier liés aux sucres, les voies de signalisation associées aux phytohormones, les signaux de stress et la photosynthèseEnvironmental pollutions by xenobiotics, especially by pesticides and heavy metals derived from agricultural activities, show an important complexity of chemical composition and of spatiotemporal dynamic. Vegetative filter strips between cultivated fields and streams limit the diffusion of these residual pollutions to natural environments. However, the exact biological role of plant in these buffer strips is poorly understood in this context of environmental and ecological protection. A comparative study carried out in situ and in controlled conditions highlighted the role of plant compartment in the processes of absorption, storage and/or partial degradation of pollutants in planta. Such capability of phytoremediation depends on the maintenance of a vegetal cover in area subjected to recurring flow of pesticides, it varies according to species and leads to the structuration of vegetative filter strip communities. An integrative study in controlled conditions of plant responses to low doses of pollutants allowed to analyze at different levels of complexity the impacts of chemical stresses on the model species Arabidopsis thaliana and the grassland species Lolium perenne. Low and sublethal doses of xenobiotics, associated degradation products and heavy metals induced cryptic perturbations at metabolic and molecular levels. Multi-pollution analyses, which reflect realistic conditions of environmental exposure, highlighted complex interactive effects between pollutants in mixture and the difficulty to predict them. The mechanisms of response to these chemical stresses differ according to the species and the pollutant, and suggest differences in term of perception and/or transport of pollutants, or of coordination of molecular and metabolic responses. Arabidopsis presented a coordination of its responses toward an increase of stress metabolites, a decrease of carbon metabolites (soluble carbohydrates), in parallel with modifications of gene expressions implicated on antioxidant defences, defence against xenobiotic stresses, or phytohormone dynamic. Chemical stress leads to major modifications of nitrogen metabolism in Lolium, and perturbations of processes of photorespiration. De novo transcriptomic analysis of Lolium therefore showed that a majority of identified genes are related to signal transduction pathways, highlighting the complexity of response mechanisms and the links between metabolic signals, especially linked to carbohydrate, hormonal signaling pathways, stress signals and photosynthesis. Subtoxic chemical stress induced cryptic re-engineering of plant processes that may explain the development of tolerance for some species and their persistence in area affected by residual pollution
43
Barnhisel, Taylor. "Carbaryl Exposure to Danio rerio Leads to Activation of the Aryl Hydrocarbon Receptor Pathway." Wittenberg University Honors Theses / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=wuhonors1617979942441695.
44
Boa-Alma, Ana Sofia Ribeiro da Costa 1988. "Monitoring rates of particulate matter pollution using genetic biomarkers in small mammals." Master's thesis, 2011. http://hdl.handle.net/10451/4606.
Abstract:
Tese de mestrado. Biologia (Biologia Humana e Ambiente). Universidade de Lisboa, Faculdade de Ciências, 2011Particulate matter is a complex mixture of ultrafine, fine and coarse particles from a variety of sources. Important compounds associated with airborne particles are polycyclic aromatic hydrocarbons, among which several are established carcinogens. Reactive intermediates, which can cause direct DNA damage, are generated by their degradation. Moreover, they can enter a reaction with other pollutants, including nitrogen oxides and ozone, and generate other potential carcinogens. The aim of the present study was to analyze the genotoxic and cytotoxic effects of particulate matter and its consequences for the environment and human health, using the Algerian mouse (Mus spretus) as a bioindicator. For this purpose we used genetic biomarkers - sperm shape abnormalities assay, micronucleus test, comet assay and determination and characterization of the genetic polymorphisms of CYP1A1 gene - in addition to registration of body and internal organs weights and evaluation of the levels of particulate matter in the respiratory tract of the animals captured at sites with different concentrations of particulate matter in the districts of Lisbon and Setubal. The results showed a significant increase in liver weight with the level of pollution, as well as an increase in the number of micronuclei and comet score. Relatively to the sperm shape abnormalities assay, there were no differences between the three groups. Through the analysis of semi-thin and electron microscopy lung cuts it was observed that some of the animals from Paio Pires had apparently macrophages with phagocytized particles, which was not observed in the animals from Lourinhã, but it is not possible to draw objective conclusions since the work was not completed. For CYP1A1 gene, it was only possible its amplification and therefore also can not draw conclusions. Then, this work can provide important information on how particles affect our health in a real environment.
O ar que respiramos está poluído com os subprodutos da combustão da indústria, geração de energia e transporte, bem como o fabrico e utilização de produtos químicos. Os principais poluentes atmosféricos na Europa e América do Norte são o dióxido de enxofre, óxidos de azoto, partículas inaláveis e ozono. Os poluentes do ar podem aparecer na forma de partículas sólidas, gotículas ou gases. Além disso, podem ser naturais ou fabricados pelo homem. As fontes de poluição do ar referem-se aos vários locais, actividades ou factores que são responsáveis pela liberação de poluentes para a atmosfera. Em concentrações suficientes, estes gases e partículas podem prejudicar a saúde humana a curto (ardor nos olhos e garganta, dificuldade em respirar) e a longo prazo (cancro e danos a longo prazo nos sistemas imunológico, neurológico, reprodutivo e respiratório). Os mecanismos pelos quais a poluição do ar influencia negativamente algumas comorbidades não são bem compreendidos. Mecanismos possíveis, como o influxo de cálcio aumentado quando em contacto com macrófagos, activação de mediadores pró-inflamatórios, viscosidade do sangue aumentada, aumento do fibrinogénio e dos níveis de proteína C-reactiva e alterações na reologia do sangue favorecendo a coagulação, têm sido sugeridos. O stress oxidativo gerado pela poluição do ar também tem sido proposto como um mecanismo importante de lesão tecidual que leva à inflamação pulmonar e sistémica. Segundo dados científicos de 2004, o excesso de partículas inaláveis provoca em Portugal quase 4000 mortes prematuras e uma redução de 6 meses na esperança média de vida dos habitantes do Porto e Lisboa (estudo da Agência Europeia do Ambiente). A Organização Mundial da Saúde estima que as doenças associadas à poluição do ar causadas por partículas inaláveis podem ser consideradas dentro das dez principais causas de morte nos países desenvolvidos. "Partículas inaláveis" é, então, um termo geral que engloba as partículas de poeira, fuligem queimada, partículas de exaustão diesel e hidrocarbonetos aromáticos policíclicos. As partículas inaláveis têm contribuições tanto de fontes primárias (ou seja, emitidas directamente na atmosfera) como de processos secundários (ou seja, formadas na atmosfera a partir de emissões de substâncias precursoras). Tanto as emissões primárias como as emissões precursoras secundárias podem ser originadas a partir de qualquer origem antropogénica ou natural. Enquanto que as partículas maiores que as PM10 não são muito susceptíveis de atingir o tracto respiratório inferior, as partículas grossas (PM10) podem chegar tão longe quanto os brônquios. As partículas finas (PM2.5) podem penetrar mais profundamente e atingir os alvéolos, assim como as partículas de exaustão diesel, que estão na faixa de tamanho das partículas finas (0.1-2.5 μm) e ultrafinas (<0.1 μm). Compostos importantes associados às partículas em suspensão são os, já referidos, hidrocarbonetos aromáticos policíclicos, entre os quais vários são estabelecidos carcinogéneos. Os hidrocarbonetos aromáticos policíclicos carcinogénicos tornaram-se recentemente o centro da atenção devido ao seu efeito potencial na etiologia do cancro, doenças respiratórias e cardiovasculares e mortalidade. Os hidrocarbonetos aromáticos policíclicos carcinogénicos são componentes da matéria orgânica ligada às partículas aerosóis inaláveis (<2.5 μm). Intermediários reactivos, que podem causar danos directos no DNA, são gerados pela sua degradação. Além disso, eles podem induzir uma reacção com outros poluentes, nomeadamente óxidos de azoto e ozono, além de gerar outros potenciais cancerígenos. A biomonitorização ambiental pode fazer uso de organismos “sentinela” que vivem no seu habitat natural e reflectir uma exposição contínua, a longo prazo. Estudos de pequenos mamíferos, principalmente roedores selvagens, têm demonstrado uma capacidade de acumular um amplo espectro de poluentes. Assim, eles são adequados para a monitorização da poluição ambiental e risco de exposição de pessoas que vivem numa área contaminada, além de serem geralmente abundantes em áreas facilmente identificadas e rapidamente capturados. Quando se trata da monitorização da genotoxicidade no ambiente, uma questão de suma importância, para além da selecção adequada de organismos representativos como sentinelas, é a realização de testes sensíveis e confiáveis, tais como aqueles projectados para a avaliação de danos no DNA. Independentemente das características particulares do evento de contaminação como um todo, é também muito importante que o ensaio de escolha tenha sido devidamente validado por laboratórios no mundo inteiro e que possa ser usado para monitorizar praticamente qualquer espécie selvagem potencialmente ameaçada. Desta forma, o objectivo do presente estudo foi analisar os efeitos genotóxicos e citotóxicos das partículas inaláveis e as suas consequências para o meio ambiente e para a saúde humana, utilizando o rato argelino (Mus spretus) como bioindicador. Para este efeito, foram utilizados biomarcadores genéticos em animais de locais com diferentes concentrações de partículas inaláveis nos distritos de Lisboa e Setúbal. Objectivos específicos podem ser apontados: avaliação do papel do rato argelino (Mus spretus) como um indicador de poluição ambiental; identificação de efeitos adversos, ou seja, mudanças de peso nos órgãos dos ratinhos e comparação com os níveis de exposição; avaliação dos níveis de partículas inaláveis no tracto respiratório dos animais capturados; avaliação dos efeitos genotóxicos e citotóxicos das partículas inaláveis através do teste das anomalias dos espermatozóides, teste do micronúcleo e ensaio do cometa; determinação e caracterização dos polimorfismos genéticos do gene CYP1A1, envolvidos no metabolismo de xenobióticos, incluindo hidrocarbonetos aromáticos policíclicos; confirmação do risco para a saúde pública e ambiental causado pela poluição por partículas inaláveis. Assim, os animais foram capturados nas três zonas seleccionadas de acordo com os níveis de poluição por partículas inaláveis. Depois de sacrificados, foram feitas medições morfológicas, ou seja, tirados os pesos e medidas corporais e dos órgãos internos e feito o teste das anomalias dos espermatozóides, o teste do micronúcleo e o ensaio do cometa. Para além disso, foi também retirado o músculo para análise genética, nomeadamente, a determinação dos polimorfismos do gene CYP1A1 e feita a observação em microscopia electrónica de transmissão de macrófagos presentes nos pulmões dos animais capturados, com o intuito de encontrar partículas fagocitadas. Como resultado, pôde-se observar medidas corporais superiores nos animais de Paio Pires, assim como o peso relativo do fígado, baço, rins e testículos. Tal seria de esperar visto o fígado ser o principal órgão essencialmente exposto a substâncias tóxicas e essenciais que entram no organismo através de inalação ou ingestão e o baço ser bastante sensível a infecções. Ao contrário do teste das anomalias dos espermatozóides que não revelou diferenças significativas entre os grupos, o que poderá ser devido em parte a artefactos técnicos, o teste do micronúcleo e o ensaio do cometa mostraram valores superiores com o aumento do nível de poluição por partículas inaláveis. Para além disto, também foi possível amplificar o gene CYP1A1, mas a determinação dos seus polimorfismos não pôde ser concluída, assim como a microanálise das possíveis partículas observadas em microscopia electrónica. Através deste estudo pode-se concluir que a inalação de partículas em altas concentrações tem um risco genotóxico significativo que pode induzir danos no DNA e, consequentemente, levar a sérios problemas de saúde. Embora este trabalho esteja dirigido para o estudo dos efeitos que as partículas inaláveis têm sobre a saúde dos seres vivos, é natural que outros xenobióticos possam ser responsáveis por alguns dos efeitos adversos registados. No entanto, embora não possamos manipular e controlar muitas das variáveis, este tipo de estudo é muito útil para analisar os efeitos da poluição como um todo e exactamente da maneira como ela nos afecta. No laboratório podemos controlar essas variáveis, mas apenas observamos os efeitos que cada poluente pode ter e não os efeitos da interacção entre todos eles, além do facto de que as doses de poluentes podem por vezes ser administradas em quantidades muito diferentes do registado num ambiente real. Os nossos resultados podem fornecer informações valiosas sobre os riscos para a saúde decorrentes de partículas urbanas e industriais, assim, alertando-nos para a necessidade da utilização de biomarcadores de efeitos, exposição e susceptibilidade e estabelecer medidas de prevenção antes de sermos confrontados com a carga social e o custo económico das doenças causadas pela poluição atmosférica por partículas inaláveis. Assim, neste trabalho foi utilizado o Mus spretus como espécie bioindicadora dos efeitos que a poluição ambiental, especificamente por partículas inaláveis, pode ter sobre a saúde, sendo possível, dentro de certos limites e sempre com cautela, transferir estes dados para os seres humanos.
45
Chang, Yung-Chen, and 張永正. "Application of Penalty-Function Genetic Algorithms Method to Pollution Control for Generator Research." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/2dv74v.
Abstract:
碩士逢甲大學
電機工程所
91
The trade of the quota of the greenhouse gases exhausts measure has gradually become another rising stock goods market. Some enterprises that haven’t run out of the quotas will sell their remainder to those that have used up or are using up the quotas. Therefore, this thesis presents a set of equal and rational principles in the separate electricity generation system of the stock goods market to deal with 1 MW of the electricity generated by different generators with different fuels. Namely, the thesis plans to set up a set of rules for the combustion efficiency of electricity generation machinery to control the allowable quota of the pollution amount produced by electricity generation. They are used not only in the trade of the generator agents’ quota of pollution amount, but also in the purpose of controlling the pollution amount of electricity generation. In this thesis, the scheme for the trade of the pollution amount uses Penalty-Function Genetic Algorithms method to determine the amount of electricity generation, conditional on the limit of the pollution amount and on the minimum cost of electricity generation. Also, the scheme is expected to determine the best price and amount of the pollution trade. On the other hand, to prove the credibility and accuracy of Penalty-Function Genetic Algorithms method, the thesis will compare this scheme, with the tradition Sequential Unconstrained Minimization Technique.
46
"DNA strand breaks in crustaceans as an indicator of marine pollution." 2005. http://library.cuhk.edu.hk/record=b5892426.
Abstract:
Chan Kwan-ling.Thesis (M.Phil.)--Chinese University of Hong Kong, 2005.
Includes bibliographical references (leaves 91-105).
Abstracts in English and Chinese.
Abstract --- p.i
Acknowledgements --- p.v
Contents --- p.vi
List of figures and tables --- p.ix
Chapter Chapter 1 --- Introduction
Chapter 1.1 --- Literature review --- p.1
Chapter 1.1.1 --- The effect of pollutants on the genetic materials of aquatic organisms --- p.1
Chapter 1.1.1.1 --- Response of individual to genotoxicants --- p.1
Chapter 1.1.1.2 --- Effects of genotoxicants on population structure --- p.3
Chapter 1.1.2 --- Application of genetic markers in monitoring water pollution --- p.3
Chapter 1.1.2.1 --- DNA adduct --- p.4
Chapter 1.1.2.2 --- Sister chromatid exchange (SCE) test --- p.5
Chapter 1.1.2.3 --- Micronucleus --- p.6
Chapter 1.1.2.4 --- DNA strand breaks --- p.7
Chapter 1.1.3 --- Single-cell gel electrophoresis (comet) assay --- p.9
Chapter 1.1.4 --- Test organisms for comet assay --- p.12
Chapter 1.2 --- Objective of the present study --- p.13
Chapter Chapter 2 --- Genotoxicity of pollutants on Hyale crassicornis
Chapter 2.1 --- Introduction --- p.22
Chapter 2.2 --- Materials and methods --- p.24
Chapter 2.2.1 --- Sampling of amphipods --- p.24
Chapter 2.2.2 --- Acclimation --- p.24
Chapter 2.2.3 --- Acute toxicity test --- p.26
Chapter 2.2.4 --- The effect of test duration on DNA damage --- p.27
Chapter 2.2.5 --- Effect of toxicants on DNA damage --- p.28
Chapter 2.2.6 --- Comet assay --- p.29
Chapter 2.2.7 --- Chemicals --- p.34
Chapter 2.2.8 --- Data analysis --- p.34
Chapter 2.3 --- Results --- p.34
Chapter 2.4 --- Discussion --- p.47
Chapter Chapter 3 --- Genotoxicity of hydrogen peroxide on different tissue types of Metapenaeus ensis
Chapter 3.1 --- Introduction --- p.54
Chapter 3.2 --- Materials and Methods --- p.57
Chapter 3.2.1 --- Collection and acclimation of shrimps --- p.57
Chapter 3.2.2 --- Incubation --- p.59
Chapter 3.2.3 --- Comet Assay --- p.60
Chapter 3.2.4 --- Chemicals --- p.61
Chapter 3.2.5 --- Data analysis --- p.61
Chapter 3.3 --- Results --- p.61
Chapter 3.4 --- Discussion --- p.67
Chapter Chapter 4 --- Genotoxicity of wastewater on Hyale crassicornis
Chapter 4.1 --- Introduction --- p.71
Chapter 4.2 --- Materials and Methods --- p.72
Chapter 4.2.1 --- Collection of wastewater samples --- p.72
Chapter 4.2.2 --- Metal content analysis --- p.73
Chapter 4.2.3 --- Genotoxic effect of wastewater samples on Hyale crassicornis --- p.74
Chapter 4.2.4 --- Chemicals --- p.76
Chapter 4.2.5 --- Statistical analysis --- p.77
Chapter 4.3 --- Results --- p.77
Chapter 4.3.1 --- Metals content in water samples --- p.77
Chapter 4.3.2 --- DNA damage --- p.79
Chapter 4.4 --- Discussion --- p.79
Chapter Chapter 5 --- Conclusions --- p.89
References --- p.91
47
Lai, Pei-Yu, and 賴佩瑜. "Using Genetic Algorithms to Enhance Pollution Sources Resolution of Chemical Mass Balance Receptor Model." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/26484676157365874402.
Abstract:
碩士國立中興大學
環境工程學系所
104
Chemical mass balance (CMB) receptor model is commonly used to evaluate and identify the air pollution sources and their contributions. The accuracy of CMB receptor model solutionsis rely on the professional judgments of operators. However, if the operators are not familiar with the detailed information about the investigated regions, it is easy to result in wrong judgments but hard to know whether there are more accurate solutions. Therefore, this study developed GA-CMB which integrated Genetic Algorithms (GA) and CMB receptor model to shorten the operation time of CMB analysis, and provides a set of optimal analysis results. The analysis performance of GA-CMB and CMB, include the statistical parameters and the ability to deal with collinearity of pollution source profiles, were investigated and compared by a hypothetical case study. The results show that if the similar pollution sources result in collinearity situation, it is likely to cause the misjudgment by CMB operator. However, GA-CMB still can quickly and accurately identify the correct answer of the hypothetical case. Furthermore, several realistic sampling case studies were also investigated by GA-CMB and CMB.. The results show that the degrees of freedom of the solutions obtained by GA-CMB are greater than those solved by CMB. Furthermore, CMB overestimates the mass percentage more seriously than GA-CMB. Based on the solutions obtained by GA-CMB and CMB models, the major source contributors of PM2.5 in Nantou, Chushan, and Puli are vehicular emissions(GA-CMB:14%~52%, CMB:31%~66%), followed by secondary aerosol ammonium sulfate (GA-CMB:18%~48%, CMB:14%~35%) and ammonium nitrate (GA-CMB:0%~40%, CMB:0%~32%). Furthermore, GA-CMB solutions indicated that iron and steel industry (0.2%~3%) and power industry (2%~13%) provide a long term, low percentage PM2.5 contribution to Nantou County. Since there are few stationary pollution sources in Nantou , these contributions may be transported from regions outside Nantou County.
48
Nowak, Carsten [Verfasser]. "Consequences of environmental pollution on genetic diversity in populations of the midge Chironomus riparius / von Carsten Nowak." 2007. http://d-nb.info/985801522/34.
49
Iyer, Satyajeet Krishnamurthy Hilton Amy B. Chan. "Optimization of natural attenuation with active remediation under uncertainty using a multi-objective genetic algorithm." 2004. http://etd.lib.fsu.edu/theses/available/etd-01072004-061650/.
Abstract:
Thesis (M.S.)--Florida State University, 2004.Advisor: Dr Amy B. Chan Hilton, Florida State University, College of Engineering, Dept. of Civil and Environmental Engineering. Title and description from dissertation home page (viewed June 18, 2004). Includes bibliographical references.
50
De, Leon Ricardo. "Use of gene probes and an amplification method for the detection of rotaviruses in water." 1989. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1989_653_sip1_w.pdf&type=application/pdf.