Today's microwave circuits, whether for communication, radar, or testing systems, need compact tunable microwave filters. Since different microwave circuit applications have radically different size, power, insertion loss, rejection, vibration, and thermal requirements, new filter technologies with different balances between these requirements are always desirable. Negative Refractive Index (NRI) transmission media was discovered 10 years ago with the unique property of negative phase propagation. A literature review was conducted to identify potential NRI methods for filters and other devices, but no NRI tunable filters were found. To address this gap, a family of tunable NRI bandpass filters was simulated and constructed successfully using end-coupled zeroth order resonators. Tuning was accomplished by controlling the negative phase length of the NRI sections with varactors. The resulting L-band filters exhibited a 25-40 percent tunable range, no higher order resonances, and required only one fourth the length of a coupled-line filter constructed from traditional 180 degree microstrip resonators.

Mais de metade das florestas do mundo são florestas secundárias e a sucessão determinística prevê que muitos aspectos das florestas originais serão recuperados. Por outro lado, os remanescentes florestais encontram-se em paisagens fragmentadas nas quais às alterações microclimáticas induzidas por efeitos de bordas podem levar a uma sucessão retrogressiva, denominada "secundarização". Assim, as comunidades florestais atuais tendem a convergir em termos de estrutura e funções que desempenham no ecossistema, e a compreensão da dinâmica de espécies e de comunidades tornou-se uma preocupação fundamental dos estudos florestais. A heterogeneidade do habitat, juntamente com diferenças ecofisiológicas entre espécies, leva à segregação destas ao longo de gradientes espaciais ou temporais. Aqui, avaliamos a estrutura filogenética e a variação da composição filogenética das comunidades arbóreas florestais buscando evidenciar padrões de segregação ao longo do gradiente sucessional. No segundo capítulo, avaliamos o poder preditivo das características funcionais sobre as mudanças demográficas de curto prazo (intervalo de cinco anos) de 20 espécies arbóreas subtropicais. No terceiro, comparamos a dinâmica de curto prazo de comunidades florestais secundárias e remanescentes no fragmentado bioma da Mata Atlântica. Nossos resultados mostraram que as linhagens principais segregam ao longo do gradiente sucessional devido a requerimentos conservados de nichos de clados basais, revelando sua associação funcional a florestas mais antigas, enquanto Eudicots podem ocorrer ao longo do gradiente. No nível das espécies, atributos foliares foram preditivos de mudanças demográficas de curto prazo e, no nível de comunidade, atributos foliares e massa das sementes captaram melhor as mudanças na composição funcional de curto prazo. Constatou-se o aumento de atributos conservativos em florestas secundárias e a perda de biomassa, devido à queda de grandes árvores, nas florestas remanescentes, expressando a perda de uma importante característica estrutural dessas florestas. / More than half of the natural world’s forest is secondary forest and deterministic succession predicts that many features of pre-disturbed forests will be recovered. On the other hand, remnant old-growth forests are mostly within fragmented landscapes and edge-induced microclimatic conditions may lead to a retrogressive succession, named ‘secondarization’. Thereby current forests tend to converge in terms of community structure and ecosystem function and the understanding of species and community dynamics became a main concern of forest studies. Habitat heterogeneity together with ecophysiological differences between species would carry to species segregation along spatial or temporal gradients. Here we evaluated the phylogenetic structure of communities and phylogenetic composition variation to evidence patterns of segregation along the succession of tree species. In the second chapter, we evaluated the predictive power of the functional traits on short-term demographic changes (five years interval) of 20 subtropical tree species. In the third, we compared the short-term dynamics of secondary and old-growth forest communities in the fragmented Atlantic forest biome. Our results showed that the main lineages segregate along the successional gradient due to conserved niche requirements of the earlydivergent clades reveling their functional association to older successional forests, whereas Eudicots can occur over the gradient. At species level, leaf functional traits were predictive of the short-term demographic changes and, at the community level, leaf traits and seed mass better captured the short-term functional composition changes of the communities. We found the rise of conservative traits at secondary forests and biomass loss, due to fall of big trees, at the old-growth communities expressing the loss of an important structural feature of these forests.

Mais de metade das florestas do mundo são florestas secundárias e a sucessão determinística prevê que muitos aspectos das florestas originais serão recuperados. Por outro lado, os remanescentes florestais encontram-se em paisagens fragmentadas nas quais às alterações microclimáticas induzidas por efeitos de bordas podem levar a uma sucessão retrogressiva, denominada "secundarização". Assim, as comunidades florestais atuais tendem a convergir em termos de estrutura e funções que desempenham no ecossistema, e a compreensão da dinâmica de espécies e de comunidades tornou-se uma preocupação fundamental dos estudos florestais. A heterogeneidade do habitat, juntamente com diferenças ecofisiológicas entre espécies, leva à segregação destas ao longo de gradientes espaciais ou temporais. Aqui, avaliamos a estrutura filogenética e a variação da composição filogenética das comunidades arbóreas florestais buscando evidenciar padrões de segregação ao longo do gradiente sucessional. No segundo capítulo, avaliamos o poder preditivo das características funcionais sobre as mudanças demográficas de curto prazo (intervalo de cinco anos) de 20 espécies arbóreas subtropicais. No terceiro, comparamos a dinâmica de curto prazo de comunidades florestais secundárias e remanescentes no fragmentado bioma da Mata Atlântica. Nossos resultados mostraram que as linhagens principais segregam ao longo do gradiente sucessional devido a requerimentos conservados de nichos de clados basais, revelando sua associação funcional a florestas mais antigas, enquanto Eudicots podem ocorrer ao longo do gradiente. No nível das espécies, atributos foliares foram preditivos de mudanças demográficas de curto prazo e, no nível de comunidade, atributos foliares e massa das sementes captaram melhor as mudanças na composição funcional de curto prazo. Constatou-se o aumento de atributos conservativos em florestas secundárias e a perda de biomassa, devido à queda de grandes árvores, nas florestas remanescentes, expressando a perda de uma importante característica estrutural dessas florestas. / More than half of the natural world’s forest is secondary forest and deterministic succession predicts that many features of pre-disturbed forests will be recovered. On the other hand, remnant old-growth forests are mostly within fragmented landscapes and edge-induced microclimatic conditions may lead to a retrogressive succession, named ‘secondarization’. Thereby current forests tend to converge in terms of community structure and ecosystem function and the understanding of species and community dynamics became a main concern of forest studies. Habitat heterogeneity together with ecophysiological differences between species would carry to species segregation along spatial or temporal gradients. Here we evaluated the phylogenetic structure of communities and phylogenetic composition variation to evidence patterns of segregation along the succession of tree species. In the second chapter, we evaluated the predictive power of the functional traits on short-term demographic changes (five years interval) of 20 subtropical tree species. In the third, we compared the short-term dynamics of secondary and old-growth forest communities in the fragmented Atlantic forest biome. Our results showed that the main lineages segregate along the successional gradient due to conserved niche requirements of the earlydivergent clades reveling their functional association to older successional forests, whereas Eudicots can occur over the gradient. At species level, leaf functional traits were predictive of the short-term demographic changes and, at the community level, leaf traits and seed mass better captured the short-term functional composition changes of the communities. We found the rise of conservative traits at secondary forests and biomass loss, due to fall of big trees, at the old-growth communities expressing the loss of an important structural feature of these forests.

Mais de metade das florestas do mundo são florestas secundárias e a sucessão determinística prevê que muitos aspectos das florestas originais serão recuperados. Por outro lado, os remanescentes florestais encontram-se em paisagens fragmentadas nas quais às alterações microclimáticas induzidas por efeitos de bordas podem levar a uma sucessão retrogressiva, denominada "secundarização". Assim, as comunidades florestais atuais tendem a convergir em termos de estrutura e funções que desempenham no ecossistema, e a compreensão da dinâmica de espécies e de comunidades tornou-se uma preocupação fundamental dos estudos florestais. A heterogeneidade do habitat, juntamente com diferenças ecofisiológicas entre espécies, leva à segregação destas ao longo de gradientes espaciais ou temporais. Aqui, avaliamos a estrutura filogenética e a variação da composição filogenética das comunidades arbóreas florestais buscando evidenciar padrões de segregação ao longo do gradiente sucessional. No segundo capítulo, avaliamos o poder preditivo das características funcionais sobre as mudanças demográficas de curto prazo (intervalo de cinco anos) de 20 espécies arbóreas subtropicais. No terceiro, comparamos a dinâmica de curto prazo de comunidades florestais secundárias e remanescentes no fragmentado bioma da Mata Atlântica. Nossos resultados mostraram que as linhagens principais segregam ao longo do gradiente sucessional devido a requerimentos conservados de nichos de clados basais, revelando sua associação funcional a florestas mais antigas, enquanto Eudicots podem ocorrer ao longo do gradiente. No nível das espécies, atributos foliares foram preditivos de mudanças demográficas de curto prazo e, no nível de comunidade, atributos foliares e massa das sementes captaram melhor as mudanças na composição funcional de curto prazo. Constatou-se o aumento de atributos conservativos em florestas secundárias e a perda de biomassa, devido à queda de grandes árvores, nas florestas remanescentes, expressando a perda de uma importante característica estrutural dessas florestas. / More than half of the natural world’s forest is secondary forest and deterministic succession predicts that many features of pre-disturbed forests will be recovered. On the other hand, remnant old-growth forests are mostly within fragmented landscapes and edge-induced microclimatic conditions may lead to a retrogressive succession, named ‘secondarization’. Thereby current forests tend to converge in terms of community structure and ecosystem function and the understanding of species and community dynamics became a main concern of forest studies. Habitat heterogeneity together with ecophysiological differences between species would carry to species segregation along spatial or temporal gradients. Here we evaluated the phylogenetic structure of communities and phylogenetic composition variation to evidence patterns of segregation along the succession of tree species. In the second chapter, we evaluated the predictive power of the functional traits on short-term demographic changes (five years interval) of 20 subtropical tree species. In the third, we compared the short-term dynamics of secondary and old-growth forest communities in the fragmented Atlantic forest biome. Our results showed that the main lineages segregate along the successional gradient due to conserved niche requirements of the earlydivergent clades reveling their functional association to older successional forests, whereas Eudicots can occur over the gradient. At species level, leaf functional traits were predictive of the short-term demographic changes and, at the community level, leaf traits and seed mass better captured the short-term functional composition changes of the communities. We found the rise of conservative traits at secondary forests and biomass loss, due to fall of big trees, at the old-growth communities expressing the loss of an important structural feature of these forests.

No description available.

Plusieurs études ont examiné la sensibilité aux antimicrobiens chez les bactéries d’organismes provenant de produits issus de l’aquaculture ou de leur environnement. Aucune information n’est cependant disponible concernant la résistance aux antimicrobiens dans les bactéries de la flore de poissons ou de fruits de mer vendus au détail au Canada. C’est particulièrement vrai en ce qui a trait aux bactéries des genres Aeromonas et Vibrio, dont certaines espèces sont des agents pathogènes zoonotiques connus. Au cours de cette étude, la sensibilité aux antimicrobiens d’isolats d’Aeromonas spp. et de Vibrio spp. provenant de poissons et de crevettes domestiques et importés a été mesurée à l’aide de techniques de micro dilution en bouillon et/ou de diffusion sur disque. Les classes d’antimicrobiens examinés comprenaient les tétracyclines (TET), les inhibiteurs de la voie des folates (sulfadiméthoxine-triméthoprime, SXT), le florfenicol (FLO), et les quinolones (acide nalidixique / enrofloxacine, NA/ENO). Des valeurs seuils épidémiologiques pour Aeromonas et Vibrio ont été établies en utilisant la méthode d’interprétation normalisée des données de résistance provenant de diffusion sur disque. La recherche de gènes de résistance associés au profil de résistance des isolats a été effectuée en utilisant des PCRs et des puces ADN. Le nombre d’isolats résistants aux divers antimicrobiens parmi les 201 isolats d’Aeromonas et les 185 isolats de Vibrio étaient respectivement les suivants: TET (n=24 et 10), FLO (n=1 et 0), SXT (n=2 et 8), NA (n=7 et 5) et ENO (n= 5 et 0). Diverses associations de gènes tet(A), tet(B), tet(E), floR, sul1, sul2, et intI1 ont été détectées, les gènes tet(E), intI1, sul2 et tet(B) étant les plus communs. Les espèces d’Aeromonas et de Vibrio isolées de poissons au détail et de fruits de mer peuvent héberger une variété de gènes de résistance, bien que peu fréquemment. Le risque que représente ces gènes de résistance reste à évaluer en considérant le potentiel infectieux des bactéries, l’utilisation des ces agents antimicrobiens pour le traitement des maladies en aquaculture et en médecine humaine et leur rôle en tant que réservoir de la résistance antimicrobienne. / Multiple studies have examined antimicrobial susceptibility in bacteria from aquacultured products microorganisms and their environment. However, no information is available concerning antimicrobial resistance in bacterial flora of fish and seafood available at the retail level in Canada. This is particularly true for the common aquatic commensals, Aeromonas and Vibrio, for which some species are known zoonotic pathogens. In the course of this study, the antimicrobial susceptibility among Aeromonas spp. and Vibrio spp. from domestic and imported fish and seafood was characterized. Aeromonas and Vibrio spp. isolates cultured from finfish and shrimp samples were evaluated for antimicrobial susceptibility by broth microdilution and/or disk diffusion techniques. Antimicrobial classes examined in detail included: tetracyclines (TET), folate pathway inhibitors (sulfadimethoxine-trimethoprim, SXT), florfenicol (FLO), and the quinolones (nalidixic acid / enrofloxacin, NA/ENO). Epidemiological cut-off values (ECV’s) for Aeromonas/Vibrio were established using normalized resistance interpretation (NRI) of disk diffusion data. Isolates were further examined by PCR and microarray for genes associated with their antimicrobial resistance. Of 201 Aeromonas and 185 Vibrio isolates, those classified as resistant were as follows, respectively: TET (n=24 and 10), FLO (n=1 and 0), SXT (n=2 and 8), NA (n=7 and 5) and ENO (n=5 and 0). Various combinations of tet(A), tet(B), tet(E), floR, sul1, sul2 and intI1 genes were detected with tet(E), intI1, sul2 and tet(B) being the most common. Vibrio and Aeromonas species isolated from retail fish and seafood sources can harbor a variety of resistance determinants, although their occurrence is not high. The risk represented by these resistances remains to be evaluated in view of the potential for bacterial infection and their role as a reservoir for antimicrobial resistance.

Plusieurs études ont examiné la sensibilité aux antimicrobiens chez les bactéries d’organismes provenant de produits issus de l’aquaculture ou de leur environnement. Aucune information n’est cependant disponible concernant la résistance aux antimicrobiens dans les bactéries de la flore de poissons ou de fruits de mer vendus au détail au Canada. C’est particulièrement vrai en ce qui a trait aux bactéries des genres Aeromonas et Vibrio, dont certaines espèces sont des agents pathogènes zoonotiques connus. Au cours de cette étude, la sensibilité aux antimicrobiens d’isolats d’Aeromonas spp. et de Vibrio spp. provenant de poissons et de crevettes domestiques et importés a été mesurée à l’aide de techniques de micro dilution en bouillon et/ou de diffusion sur disque. Les classes d’antimicrobiens examinés comprenaient les tétracyclines (TET), les inhibiteurs de la voie des folates (sulfadiméthoxine-triméthoprime, SXT), le florfenicol (FLO), et les quinolones (acide nalidixique / enrofloxacine, NA/ENO). Des valeurs seuils épidémiologiques pour Aeromonas et Vibrio ont été établies en utilisant la méthode d’interprétation normalisée des données de résistance provenant de diffusion sur disque. La recherche de gènes de résistance associés au profil de résistance des isolats a été effectuée en utilisant des PCRs et des puces ADN. Le nombre d’isolats résistants aux divers antimicrobiens parmi les 201 isolats d’Aeromonas et les 185 isolats de Vibrio étaient respectivement les suivants: TET (n=24 et 10), FLO (n=1 et 0), SXT (n=2 et 8), NA (n=7 et 5) et ENO (n= 5 et 0). Diverses associations de gènes tet(A), tet(B), tet(E), floR, sul1, sul2, et intI1 ont été détectées, les gènes tet(E), intI1, sul2 et tet(B) étant les plus communs. Les espèces d’Aeromonas et de Vibrio isolées de poissons au détail et de fruits de mer peuvent héberger une variété de gènes de résistance, bien que peu fréquemment. Le risque que représente ces gènes de résistance reste à évaluer en considérant le potentiel infectieux des bactéries, l’utilisation des ces agents antimicrobiens pour le traitement des maladies en aquaculture et en médecine humaine et leur rôle en tant que réservoir de la résistance antimicrobienne. / Multiple studies have examined antimicrobial susceptibility in bacteria from aquacultured products microorganisms and their environment. However, no information is available concerning antimicrobial resistance in bacterial flora of fish and seafood available at the retail level in Canada. This is particularly true for the common aquatic commensals, Aeromonas and Vibrio, for which some species are known zoonotic pathogens. In the course of this study, the antimicrobial susceptibility among Aeromonas spp. and Vibrio spp. from domestic and imported fish and seafood was characterized. Aeromonas and Vibrio spp. isolates cultured from finfish and shrimp samples were evaluated for antimicrobial susceptibility by broth microdilution and/or disk diffusion techniques. Antimicrobial classes examined in detail included: tetracyclines (TET), folate pathway inhibitors (sulfadimethoxine-trimethoprim, SXT), florfenicol (FLO), and the quinolones (nalidixic acid / enrofloxacin, NA/ENO). Epidemiological cut-off values (ECV’s) for Aeromonas/Vibrio were established using normalized resistance interpretation (NRI) of disk diffusion data. Isolates were further examined by PCR and microarray for genes associated with their antimicrobial resistance. Of 201 Aeromonas and 185 Vibrio isolates, those classified as resistant were as follows, respectively: TET (n=24 and 10), FLO (n=1 and 0), SXT (n=2 and 8), NA (n=7 and 5) and ENO (n=5 and 0). Various combinations of tet(A), tet(B), tet(E), floR, sul1, sul2 and intI1 genes were detected with tet(E), intI1, sul2 and tet(B) being the most common. Vibrio and Aeromonas species isolated from retail fish and seafood sources can harbor a variety of resistance determinants, although their occurrence is not high. The risk represented by these resistances remains to be evaluated in view of the potential for bacterial infection and their role as a reservoir for antimicrobial resistance.

yes / Stakeholder topics are one of the main ideas in development thinking that have been introduced in the last few years, certainly a concept of the 1990s. The use of stakeholder language and the application of analysis, planning and management methods directed towards different interest groups are increasingly becoming commonplace, especially amongst some anglophone donors, Three main general applications of stakeholder ideas have been developed in the literature: - the involvement of Stakeholders in Participatory methods of Development intended to achieve sustainable poverty relief; - the use of Stakeholder Analysis to assure the implementation soundness of development projects; and - its use as a means of understanding the many economic interests and processes that relate to "systems" for Natural Resource Management, this understanding to be applied in a number of developmentally beneficial uses.Naturally the three strands of applying stakeholder ideas draw from each other. This paper looks at the emergence of thinking and applications from them all, leading towards a more full consideration of the application of Stakeholder Analysis in the planning of projects of various kinds. / ID-7098D - Project Planning and Financial Analysis

The electromagnetic coupling of a microstrip transmission line (MS-TL) to a metamaterial backward wave Negative-Refractive-Index transmission line (NRI-TL) is the primary investigation of this dissertation. The coupling of forward waves in the MS-TL to the backward waves in the NRI-TL results in the formation of complex modes, characterized by simultaneous phase progression and attenuation along the lossless lines. Through network-theoretic considerations, we investigate the properties of these modes in the complex-frequency plane of the Laplace domain to help unravel the confusion that has existed in the literature regarding the independent excitation of a pair of conjugate complex modes. We show that it is possible to arbitrarily suppress one of the modes over a finite bandwidth and completely eliminate it at a discrete set of frequencies using proper source and load impedances. Hence we use conjugate modes with independent amplitudes in our eigenmode expansion when we analyse various coupling configurations between the two types of lines (MS/NRI-TL coupler). We derive approximate closed-form expression for the scattering parameters of the MS/NRI-TL coupler and these are complemented by design charts that allow the synthesis of a wide range of specifications. Moreover, these expressions reveal that such couplers allow for arbitrary backward coupling levels along with very high-isolation when they are made half a guided wavelength long. The MS/NRI-TL coupler offers some interesting applications which we highlight through the design and testing of a 3-dB power splitter, a high-directivity signal monitor and a compact corporate power divider. We have included design, simulation and experimental data for the fabricated prototypes exhibiting good agreement and thereby justifying the theory that has been developed in this work to explain the coupling between a right-handed MS-TL and a left-handed NRI-TL.

The electromagnetic coupling of a microstrip transmission line (MS-TL) to a metamaterial backward wave Negative-Refractive-Index transmission line (NRI-TL) is the primary investigation of this dissertation. The coupling of forward waves in the MS-TL to the backward waves in the NRI-TL results in the formation of complex modes, characterized by simultaneous phase progression and attenuation along the lossless lines. Through network-theoretic considerations, we investigate the properties of these modes in the complex-frequency plane of the Laplace domain to help unravel the confusion that has existed in the literature regarding the independent excitation of a pair of conjugate complex modes. We show that it is possible to arbitrarily suppress one of the modes over a finite bandwidth and completely eliminate it at a discrete set of frequencies using proper source and load impedances. Hence we use conjugate modes with independent amplitudes in our eigenmode expansion when we analyse various coupling configurations between the two types of lines (MS/NRI-TL coupler). We derive approximate closed-form expression for the scattering parameters of the MS/NRI-TL coupler and these are complemented by design charts that allow the synthesis of a wide range of specifications. Moreover, these expressions reveal that such couplers allow for arbitrary backward coupling levels along with very high-isolation when they are made half a guided wavelength long. The MS/NRI-TL coupler offers some interesting applications which we highlight through the design and testing of a 3-dB power splitter, a high-directivity signal monitor and a compact corporate power divider. We have included design, simulation and experimental data for the fabricated prototypes exhibiting good agreement and thereby justifying the theory that has been developed in this work to explain the coupling between a right-handed MS-TL and a left-handed NRI-TL.