Groundwater contaminants such as chlorinated ethenes, chlorinated ethanes and nitroaromatic explosive compounds (e.g. 2,4,6-Trinitrotoluene (TNT)) degrade in the subsurface primarily by microbially catalyzed reductive transformation reactions. From a regulatory point of view, the capability to simulate the kinetics of these reductive transformation reactions coupled with other attenuation processes in the subsurface (e.g., sorption, advection, and dispersion) is required for site-specific solute transport models. A kinetic model based on Michaelis-Menten type equations (Widdowson 2004) has been successfully validated for the linear reductive dechlorination pathway of chlorinated ethenes, and implemented in solute transport codes such as SEAM3D (Waddill and Widdowson 2000). However, TNT degrades through more complex branched pathways, and kinetic models are lacking in the current literature. This research study was undertaken with the objective of extending the kinetic model developed for the linear reductive pathway of chlorinated ethenes to branched pathways. The proposed extended kinetic model was validated with experimental concentration-time data of TNT and its metabolites from two prior published laboratory studies (Daun et al. 2000; Hwang et al. 2000), both in the presence and absence of sorption. The model-predicted concentrations with time of TNT and its degradation intermediates and end-products correlated well with the experimental data. The model is further compatible with and can be easily incorporated into solute transport codes (e.g., SEAM3D), and used to evaluate the fate and transport of TNT and other similar contaminants in the subsurface. / Master of Science

TNT (2,4,6-trinitrotoluene) readily and predominantly transforms to 2ADNT (2-amino-4,6-dinitrotoluene) and 4ADNT (4-amino-2,6-dinitrotoluene) in environmental matrixes and tissues. Solid phase microextraction (SPME) was used to extract ADNTs (amino-dinitrotoluenes) from tissue as a potential method to investigate the recalcitrance of metabolically-generated ADNTs versus absorbed ADNTs. Tubifex tubifex was allowed to metabolize TNT into ADNTs in 24-hr static non-renewal exposure test followed by 24-hr depuration in clean reconstituted hard water. Polyacrylate-coated (PA) SPME fibers were then deployed and agitated in tissue homogenates containing metabolically-generated ADNTs for 48 hr to provide a measure of available ADNTs. Extractability of ADNTs from T. tubifex tissue containing metabolically-generated ADNTs was significantly less than extractability of ADNTs from T. tubifex tissue containing absorbed ADNTs: 50-60% and 81-90% of expected extractability based on fiber-water partition ratio. The lower SPME extractability of metabolically-generated ADNTs may stem from the unavailability of metabolically-generated ADNTs sequestered in tissue or bound to tissue macromolecules during metabolism of TNT to ADNT. Tissue extractions using SPMEs may be able to estimate such bound organic residues in tissue and serve as potential indicators of toxicological bioavailability and biomagnification potential of tissue-associated organic compounds.

Vlivy a přínosy expresní přepravy na rozvoj ekonomiky a na proces globalizace. Analýza mezinárodních expresních kurýrních společností přítomných na českém trhu. Porovnání kvality a rozsahu jimi nabízených služeb.

Diploma thesis deals the process of choosing the optimal method of the shipping with TNT Express. The theoretical part is devoted to definiton of the particular methods of transportation. The aim of the operative part is to highlight and solve the problem within the internal communication between salesmen and Special Services Agents.

Poplar (Populus deltoides x nigra DN34) tissue cultures removed 2,4,6-trinitrotoluene (TNT) from an aqueous solution in five days, reducing the toxicity of the solution from highly toxic Microtox® EC value to that of the control. 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) was taken up by the plant tissue cultures more slowly, but toxicity reduction of the solution was evident. The measurement of toxicity reduction of aqueous solutions containing TNT and RDX was performed using a novel methodology developed for use with the Microtox® testing system. Radiolabeled TNT and RDX were used to confirm removal of explosives from hydroponic solutions containing plant tissue cultures and to verify that toxicity did not change in solutions where no plant cultures were present (positive controls). High Performance Liquid Chromatography (HPLC) and Liquid Scintillation Counter (LSC) measurements confirmed removal of TNT and RDX from solutions containing poplar plant tissue cultures and constancy of the plant-free controls. In addition, metabolites were identified in remediated solutions by HPLC, confirming the mechanism by which plants can remediate groundwater, surface water, and soil solutions. Using an Affymetrix® microarray, poplar trees were exposed to TNT over 48 hours. General patterns, as well as significant downregulated and upregulated genes were studied. We identified several new genes that were implicated in the detoxification and metabolism of TNT by Populus. In particular, our results support the "green liver" model of different gene families being expressed during the time course experiments. This suggests an alignment with Phase I transformation, Phase II conjugation, and Phase III compartmentation processes. Many of the genes identified in this study were related to those significantly expressed in previous Arabidopsis studies, supporting the comparison between these two plants. Gene families represented as significant in this study were glucosyltransferases, glycosyltransferases, cytochromes, and phosphofructokinases. We saw patterns in the areas of respiration, citric acid cycle, shikimatic pathway, and toxic responses.

The energetic compounds TNT (2,4,6-trinitrotoluene), RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine), and HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) contaminate military testing ranges worldwide yet are known to be degraded by plants and microbes in the laboratory. However, these contaminants remain persistent in the environment and represent a health threat to both humans and ecosystems. The use of traditional soil remediation technologies, such as landfilling or incineration, require large excavation costs and disrupt the ecology of the site. Phytoremediation, the use of green plants for the in situ treatment of contaminants, may be the most appropriate means of treating energetic residues present at military testing ranges. Eglin Air Force Base (EAFB), located near Niceville, FL, is one of the largest military installations in the world and holds many plant and animal species which are threatened or endangered. The use of explosives during training exercises on firing ranges at EAFB has resulted in contamination of energetics on range soils. In an effort to increase range sustainability with respect to explosives contamination, EAFB has been established as the site where phytoremediation processes will be explored for this research.

El presente trabajo busca determinar y cuantificar el desalineamiento del Tipo de Cambio Real respecto a su trayectoria de largo plazo, y los efectos que tiene dicho desalineamiento sobre los distintos sectores de la Economía Boliviana a partir del shock positivo de precios internacionales vivido a partir del año 2003 en el contexto mundial. Para dicho fin se ha dividido el mismo en tres partes. En una primera parte se identifica la situación de dicha variable al interior de nuestra economía y se plantea el periodo de estudio (1991 – 2008). En la segunda parte se plantea todo el marco teórico a utilizarse: Se presenta el modelo de PPC, mismo que se descarta, el modelo TNT para determinación del Tipo de Cambio Real, el cual finalmente se utiliza y un modelo de Booming Sector para una economía pequeña y abierta, el cual se utiliza para el testeo de Enfermedad Holandesa. La tercera parte es la de desarrollo a partir de series estadísticas para los modelos planteados en la segunda parte. Se utiliza el Modelo TNT para la obtención del Tipo de Cambio Real, utilizando la metodología de dos pasos de Engel – Granger. El primer paso consiste en plantear y determinar un Tipo de Cambio Real de Equilibrio a partir de variables que lo determinan (Fundamentos del Tipo de Cambio Real). El segundo paso determina la velocidad de ajuste del TCR hacia su trayectoria de equilibrio de largo plazo, luego de un shock externo. Para determinar la trayectoria de equilibrio de largo plazo es necesaria la eliminación de la tendencia para ello se utilizo el filtro de Hodrick y Prescott. A partir de lo anteriormente mencionado, se obtuvo una apreciación del Tipo de Cambio Real de 16% respecto a su trayectoria de equilibrio. Una vez obtenido el resultado que arroja apreciación del Tipo de Cambio Real, se utiliza el modelo de Booming Sector dividiendo a la economía en tres sectores y se corrobora insipiente presencia de Enfermedad Holandesa en la Economía Boliviana, cuantificándose el efecto causado por el boom de precios sobre el nivel de producción sobre los tres sectores en que se divide a la economía.

Thesis (Ph.D.)--Ohio University, November, 2004. / Includes bibliographical references (p. 94-101)

Thesis (Ph.D.)--Ohio University, November, 2004. / Title from PDF t.p. Includes bibliographical references (p. 94-101)

Submitted by Danielle Karla Martins Silva (danielle.martins@ufpe.br) on 2015-03-04T12:13:39Z No. of bitstreams: 2 ME-2010.1_Taciana_Santos_CCB-UFPE.pdf: 2202200 bytes, checksum: fe7ff81b25b37bf5fbfcbd8d4e4b6fed (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-04T12:13:39Z (GMT). No. of bitstreams: 2 ME-2010.1_Taciana_Santos_CCB-UFPE.pdf: 2202200 bytes, checksum: fe7ff81b25b37bf5fbfcbd8d4e4b6fed (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2012 / CNPq / O reconhecimento de áreas de endemismo é essencial para entender a evolução espaço-temporal. Neste trabalho objetivei identificar as áreas de endemismo para mamíferos terrestres do Novo Mundo, e investigar os fatores biogeográficos e metodológicos envolvidos neste endemismo. Com dados de distribuição geográfica da IUCN, eu realizei uma PAE com todos os mamíferos excluindo as ordens Sirenia e Cetacea. Testei quadrículas de 1° ou 2°, com todos os mamíferos não aquáticos e com apenas terrestres (sem morcegos), com todas as quadrículas e removendo as ilhas, e dobrando o peso para surgimento do táxon (caractere) ou mantendo peso igual para todos os estados de caracteres. Apliquei algoritmos de parcimônia com o TNT (New Technology Search) usando em cada matriz o melhor nível de busca reconhecido em testes preliminares (encontrou a melhor resolução de árvore), e identifiquei a melhor árvore: a mais curta, e com Índice de Consistência (IC) e de Retenção (IR) mais altos. Listei os clados com valores de bootstrap ≥ 75 e com no mínimo duas sinapomorfias autênticas, e reconheci no mapa as áreas de endemismo. Buscando a árvore mais parcimoniosa com todas as matrizes do Novo Mundo, com quadrículas de 1° e 2°, removendo os táxons de ampla vagilidade ou não, excluindo as ilhas ou não, em todos os níveis de buscas testados a melhor árvore foi encontrada com quadrículas de 2° removendo os morcegos, incluindo as ilhas e não alterando o peso dos estados dos caracteres (matriz NM2°Terrestres) tendo IC = 0,13 e IR = 0,87. Identifiquei oito áreas de endemismo representando as três Américas, predominantemente na latitude tropical, em florestas de altas altitudes, com 32 espécies endêmicas representando as ordens Rodentia, Soricomorpha, Lagomorpha, Carnivora, Artiodactyla e Primates. Três espécies estão classificadas como “dados deficientes” pela IUCN e não assumi serem espécies endêmicas. Das outras 27, duas de médio porte e as outras são pequenos mamíferos. Mamíferos podem explorar vários nichos ecológicos, porém, nas áreas de endemismo no Novo Mundo percebi que fatores ecológicos, geográficos ou evolutivos devem interferir na distribuição de alguns táxons, formando as áreas de endemismo, pois existe uma forte relação dos mamíferos endêmicos do Novo Mundo com o habitat e o relevo das áreas. Reconheci que a quantidade e qualidade dos dados (tamanho e número das quadrículas, e excesso de quadrículas com mesma composição) influenciam os IC e IR da árvore, e possivelmente o excesso de táxons que ocorrem em muitas células interfira no arranjo da árvore mais parcimoniosa desvalorizando o bootstrap dos ramos e consequentemente prejudicando a identificação das áreas de endemismo.