Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 200 for “"PCBs"”.
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Effects of PCBs and PBDEs on response inhibition and dopaminergic signaling
Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are persistent environmental contaminants that share physical and neurotoxic properties. Developmental PCB exposure has been associated with impulsive behavior in laboratory species and human cohorts, while little is known …
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Morphometric changes in the prepubertal rat thyroid gland following acute exposure to PCBs
… study the effects of polychlorinated biphenyls (PCBs), were further used to examine the effects of PCBs on thyroid glands through examination of serum thyroxine (T$\sb4$) and morphometry.
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Motor and Cerebellar Effects in Rats Exposed to PCBs and Methylmercury During Early Development
Polychlorinated biphenyls (PCBs) and methylmercury (MeHg) are found in the same food sources, particularly fish and seafood, and recent studies suggest they may have additive or interactive effects on the nervous system. High doses of MeHg are known to target the cerebellum and impair balance and …
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Investigation of polyethlyene passive samplers' efficacy in deducing sediment pore water concentrations of PCBs
Polychlorinated biphenyl compounds (PCBs) were manufactured between 1929 and 1977 as heat exchange fluids, flame retardants, and pesticide extenders, among other uses. About 450 million pounds of PCBs are estimated to have entered the environment since manufacture. Assessing the hazard posed by …
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RECOVERY-RD: The Development of a Biotransformation Model for Sediment Systems Contaminated with PCBs
This thesis describes the creation of RECOVERY-RD, a numerical model capable of representing the biotransformation processes associated with Polychlorinated Biphenyl (PCB) compounds in contaminated sediments for a variety of aquatic environments, including rivers and marine systems. RECOVERY-RD is …
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The effect of protozoan grazers on the cycling of polychlorinated biphenyls (PCBs) in marine systems
… contaminants such as polychlorinated biphenyls (PCBs) and ultimately determine their residence time in a particular environment. In marine systems, the microbial loop influences organic carbon dynamics by recycling a significant fraction of dissolved and particulate organic matter. The goal of …
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The effect of protozoan grazers on the cycling of polychlorinated biphenyls (PCBs) in marine systems
… contaminants such as polychlorinated biphenyls (PCBs) and ultimately determine their residence time in a particular environment. In marine systems, the microbial loop influences organic carbon dynamics by recycling a significant fraction of dissolved and particulate organic matter. The goal of …
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Are PCBS in phytoplankton and zooplankton at equilibrium with the water in which they live?
… bioaccumulation of polychlorinated biphenyls (PCBs) can result in harmful concentrations within higher trophic level organisms such as fish and humans. It is important to consider how the concentrations of PCBs in phytoplankton and zooplankton affect higher trophic organisms. It was …
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Temporal and spatial air deposition of PBDEs and PCBs from sedimentary samples in the Great Lakes region.
Temporal and spatial air deposition of PBDEs and PCBs from sedimentary samples in the Great Lakes region.
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Investigations into the determination of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) by capillary gas chromatography
… of PAHs (16 priority PAHs as an example) and PCBs (10 PCB congeners, representing 10 isomeric groups) by capillary gas chromatography coupled with mass spectrometry (GC/MS, for PAHs) and electron capture detection (GC/ECD , for PCBs) were studied, with emphasis on the effect of solvent. Having …
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Using polyethylene passive sampling to assess transport of polychlorinated biphenyls (PCBs) between contaminated sediments, water, and biota
Polychlorinated biphenyls (PCBs), which were a widely used group of chemicals before their manufacture was banned in 1979 in the United States, still contaminate numerous aquatic systems. Although there are ongoing efforts to remediate these sites, our ability to implement effective remediation …
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Effects of polychlorinated biphenyls (PCBs) on hepatic enzyme induction, uterotropic responses, and thyroid hormone levels in prepubertal female rats
… to study effects of polychlorinated biphenyls (PCBs) on hepatic enzyme induction, uterotropic responses, and thyroid hormone levels. Three approaches have been used to study the multiple effects of PCB mixtures: (1) environmental mixtures (soil, dust and air samples) collected from the Sangamo …
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Pulse microwave mediated sample clean-up method to analyse trace metals, PCBs and pesticides, and for treatment of organic wastes
A procedure is described for open vessel pulse microwave wet ashing system. In wet ashing procedure organic matrix in biological tissues is digested in acid. This step must precede trace metal analysis by atomic absorption spectroscopy. Conventional wet ashing procedure using hot plate takes …
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The Effects of Lactational and Gestational Exposure to 2,3,7,8-Tetrachlorodibenzo-P-Dioxin or Coplanar PCBs on Spatial Learning and Memory
One way in which rats are able to solve the RAM without employing memory systems is by using a response strategy. The most obvious response strategy that would yield better performance on the RAM is adjacent arm selection. A final study was conducted, in which TCDD-exposed animals were tested on …
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Polyethylene devices and the effects of sediment resuspension on the cycling of PAHs and PCBs in the lower Hudson Estuary
In order to examine the importance of sediment resuspension on the sediment bed-to-water column transport of hydrophobic organic contaminants (HOCs) in the lower Hudson Estuary, the following areas of research were pursued: 1) a passive, in situ sampler, a polyethylene device (PED), for measuring …
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Bioremediation of polychlorinated biphenyls (PCBs) on contaminated soils : a case study of Rietvlei Farm Borehole No. 11, Limpopo Province, South Africa
Polychlorinated biphenyls (PCBs) are worldwide environmental pollutants which contaminate the environment through careless disposal practices and accidental spills or leakages from electrical transformers. These organic compounds are lipophilic chemicals soluble in fats, slightly soluble in water …
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Neurobehavioral and neurochemical effects of ortho-substituted polychlorinated biphenyl congeners in perinatally exposed rats
Polychlorinated biphenyls (PCBs) are persistent contaminants in the environment. PCBs are lipophilic and from the environment bioaccumulate in living organisms. People are exposed to PCBs through the food chain. PCB exposure during development of the central nervous system (CNS) results in …
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