This thesis examines the development of a high efficiency heat pump system using thermoelectric (TE) and reticulated metal foam (RMF) technologies to power a vehicle`s battery thermal management system. The focus is split into two areas: first a review of TE???s sourcing or removing heat, second an examination of compact heat exchanger (HX) design. Five TE suppliers were investigated to understand the performance and limitations of their TE modules. Testing showed the Kyrotherm product to be superior so it was used as a design basis. RMF???s are known to be an effective means to improve the performance of compact heat exchangers, thus HX???s were evaluated with RMF foams compressed to varying densities in order to understand their potential in conjunction with thermoelectric devices. Experimental results showed performance was limited due to adequate bonding, yet still on par with the highest efficiency technologies currently on the market.

Made available in DSpace on 2014-06-11T19:27:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-13Bitstream added on 2014-06-13T18:07:21Z : No. of bitstreams: 1 silva_lfn_me_botfmvz.pdf: 253354 bytes, checksum: 346237b24c0c8bb40efc79358dd2a8ab (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O objetivo do presente estudo foi avaliar a importância das plaquetas reticuladas nas condições trombocitopênicas associadas a hipoplasia de megacariócitos e a outras etiologias sem alteração no número de megacariócitos. Para tanto foram utilizados 30 cães sadios adultos (Grupo controle); 15 cães com trombocitopenia (< 100.000 plaquetas/mL), por causas diversas que não sejam por hipoplasia megacariocítica (Grupo A) e 15 cães com trombocitopenia (< 100.000 plaquetas/mL) e com hipoplasia megariocítica (Grupo B), constatadas por meio de citologia aspirativa de medula óssea. Foi coletado sangue e extraído o plasma rico em plaquetas para a realização da quantificação das plaquetas reticuladas em citometria de fluxo e colheita de medula óssea para a análise do número de megacariócitos por duas técnicas distintas e correlação com as plaquetas reticuladas. Não foi observada diferença estatística (p>0,05) entre as duas técnicas de quantificação de megacariócitos. Foi observada diferença estatística (p<0,05) para as plaquetas reticuladas, sendo superior nos grupos A e B, em relação ao grupo controle. Não houve correlação entre plaqueta reticulada e megacariócitos medulares. A ausência de correlação observada não nos permite estabelecer relações de contagem de PR com o aumento do número de megacariócitos na medula óssea. / The aim of this study was to evaluate the reticulated platelet importance in evaluation of platelet production in thrombocytopenic conditions associated with megakaryocytic hypoplasia and other conditions with adequate number of bone marrow megacaryocytes. These study were obtained from 30 healthy dogs (control group), 15 thrombocytopenic dogs (< 100,000 platelets/μL) without megakaryocytic hipoplasia (group A) and 15 thrombocytopenic dogs (< 100,000 platelets /μL) with megakaryocytic hipoplasia (group B). Blood samples were collected and the platelet rich plasma (PRP) was extracted for quantification of reticulated platelets in flow cytometry, megakaryocytes were quantified in marrow particles, collected from aspiration cytology and correlated to reticulated platelets counts. No statistical significance (p>0.05) was observed between two megakaryocytes quantification techniques. For reticulated platelets was observed statistical significance difference (p<0.05), values from groups A and B were higher than control group. No correlation was verified between reticulated platelets and marrow megakaryocytes. The absence of correlation do not allow us to establish relationship of reticulated platelets with increase production of bone marrow megakaryocytes.

The primary purpose of this dissertation is to investigate the stability of reticulated domes under multiple static and dynamic loads. Two elastic geometrically nonlinear structural models of a reticulated dome with 21 and 39 degrees of freedom are considered. The nonlinear response of the system to static loads is obtained using nonlinear programming and discrete perturbation techniques. The nonlinear programming technique is used to obtain a starting solution for the discrete perturbation technique and to optimize the choice of the perturbation parameter. Convergence criteria and error estimates to limit errors in a perturbation scheme are developed. A method for selecting a "suitable" perturbation parameter for imperfection sensitive systems is proposed. The investigation of stability of equilibrium of the system subjected to finite disturbances is based on the concept of "degree of stability" and the associated sufficient stability condition. The stability condition is derived from a theorem on extent of asymptotic stability of Liapunov's direct method of the theory of stability of motion. Its application requires the determination of the nonlinear fundamental path and the "nearest" unstable post-buckling path. This is obtained via static analysis. The perturbed motion of the system under a given set of perturbations is obtained by numerically integrating the nonlinear equations of motion. The dynamic stability tests confirm the sufficiency of the dynamic stability condition. However, they also indicate that there is a dynamic disturbance with a specific spatial distribution for which the sufficient condition of stability is also a necessary condition for each equilibrium state tested. Since in practice, the spatial distribution of the disturbances cannot be controlled, the sufficient dynamic stability condition employed is practical for the design of reticulated domes. The stability boundaries corresponding to two independent loads on the models are presented. Limit points lie on a boundary which is convex towards the region of stability. Bifurcation points lie on a continuous but piecewise differentiable boundary. Each piece of the boundary containing bifurcation points appears to be convex towards the region of stability. / Ph. D.

In today’s society large quantities of waste is produced. In Sweden this is reused as fuel for incineration processes where electricity and district heating are generated. However, during this process two hazardous by-products are formed, namely slag and fly ash. These contain relatively high concentrations of heavy metals, which make them harmful to the environment if not taken care of, but also make them valuable resources if the metals could be extracted and reutilized. One possible way to extract metals from the waste products is to use electrochemical methods. In order to implement these techniques on an industrial scale, there are several parameters that have to be considered. One important parameter is the choice of material of the electrode, which needs to have a large surface area, a high chemical inertness and electrical conductivity, and preferably also a reasonable price. A material that fulfills these qualifications is reticulated vitreous carbon (RVC), and therefore the extraction efficiency of this porous material has been evaluated in this thesis. Studies were also performed to evaluate how several other parameters affected the extraction efficiency, since this does not rely on the choice of electrode material alone. The results showed that RVC is suitable as electrode material for efficient metal extraction from fly ash. The most efficient electrode combination was RVC with a pore size of 10 pores per linear inch as working electrode, stainless steel as counter electrode, and Ag/AgCl as reference electrode. Both the amperometric and galvanostatic experiments extracted equal amounts of copper within the same time interval, which means that the choice of using either controlled potential or controlled current for an efficient extraction of copper was not of significant importance. The mass transfer rate for copper was 0.12 mg·h-1·cm-2 in both methods, where an electrolyte of 200 ml was used with an initial copper concentration of 50 mg/l. Regarding stirring of the electrolyte, circulation in the solution is an advantage, but not critical for an efficient reduction. The extraction efficiency for one particular metal did not seem to be affected by the presence of other metals in the electrolyte. It was also shown that a selective extraction of metals was possible by applying different potentials. Lastly, an experiment with fly ash was performed, with the optimal conditions and electrode combination based on the previous experiments. This yielded a mass transfer rate of 0.59 mg·h-1·cm-2 for zinc using an electrolyte of 200 ml, which initially contained 595 mg/l of zinc.

Concentration of microorganisms from a sample volume would increase the limits of detection of samples used for rapid-detection methods. Rapid detection methods are is advantageous for the food industry to rapidly test for bacteria in order release products on a timely basis. Ultrasonic concentration was considered a promising method for manipulation of microorganisms. An ultrasonic chamber consisting of parallel piezoceramic discs with a reticulated polyurethane foam mesh was used to concentrate Saccharomyces cerevisiae yeast and Escherichia coli bacteria. The concentration of yeast was seen to increase by 200% (from 8.0 x 104 cells mL-1 to 2.4 x 105 cells mL-1) while almost zero concentration of bacteria was observed. The poor concentration effect seen with the smaller microorganisms was explained by the volume dependent acoustic radiation force exerted on the particles; the concentration forces are 1,000 times smaller for a 1 μm bacteria cell versus a 10 μm yeast cell.

Orientador: Regina Kiomi Takahira / Banca: Leonardo Brandão / Banca: Marcelo Larami Santoro / Resumo: O objetivo do presente estudo foi avaliar a importância das plaquetas reticuladas nas condições trombocitopênicas associadas a hipoplasia de megacariócitos e a outras etiologias sem alteração no número de megacariócitos. Para tanto foram utilizados 30 cães sadios adultos (Grupo controle); 15 cães com trombocitopenia (< 100.000 plaquetas/mL), por causas diversas que não sejam por hipoplasia megacariocítica (Grupo A) e 15 cães com trombocitopenia (< 100.000 plaquetas/mL) e com hipoplasia megariocítica (Grupo B), constatadas por meio de citologia aspirativa de medula óssea. Foi coletado sangue e extraído o plasma rico em plaquetas para a realização da quantificação das plaquetas reticuladas em citometria de fluxo e colheita de medula óssea para a análise do número de megacariócitos por duas técnicas distintas e correlação com as plaquetas reticuladas. Não foi observada diferença estatística (p>0,05) entre as duas técnicas de quantificação de megacariócitos. Foi observada diferença estatística (p<0,05) para as plaquetas reticuladas, sendo superior nos grupos A e B, em relação ao grupo controle. Não houve correlação entre plaqueta reticulada e megacariócitos medulares. A ausência de correlação observada não nos permite estabelecer relações de contagem de PR com o aumento do número de megacariócitos na medula óssea. / Abstract: The aim of this study was to evaluate the reticulated platelet importance in evaluation of platelet production in thrombocytopenic conditions associated with megakaryocytic hypoplasia and other conditions with adequate number of bone marrow megacaryocytes. These study were obtained from 30 healthy dogs (control group), 15 thrombocytopenic dogs (< 100,000 platelets/μL) without megakaryocytic hipoplasia (group A) and 15 thrombocytopenic dogs (< 100,000 platelets /μL) with megakaryocytic hipoplasia (group B). Blood samples were collected and the platelet rich plasma (PRP) was extracted for quantification of reticulated platelets in flow cytometry, megakaryocytes were quantified in marrow particles, collected from aspiration cytology and correlated to reticulated platelets counts. No statistical significance (p>0.05) was observed between two megakaryocytes quantification techniques. For reticulated platelets was observed statistical significance difference (p<0.05), values from groups A and B were higher than control group. No correlation was verified between reticulated platelets and marrow megakaryocytes. The absence of correlation do not allow us to establish relationship of reticulated platelets with increase production of bone marrow megakaryocytes. / Mestre

The southeastern United States is a global biodiversity hotspot but has experienced severe declines of natural ecosystems. The southeast is currently facing widespread change, particularly from an increasing human population and climate change, that is likely to impact all remaining natural areas to some degree. In this work, I examine some of the challenges currently facing imperiled species of reptiles and amphibians in this region. The work is focused on two species, the Reticulated Flatwoods Salamander (Ambystoma bishopi) and the Eastern Indigo Snake (Drymarchon couperi) both of which are listed on the U.S. Endangered Species List. Chapter 1 used Light Detection and Ranging (LiDAR) data to measure wetland bathymetry (basin shape) in flatwoods salamander breeding wetlands. Bathymetry data were used to construct stage–area relationships for each wetland, and a history of water level monitoring data were applied to these relationships to build multi-year time series of flooded area metrics. These metrics were then combined with an assessment of vegetation characteristics to map potentially suitable habitat for flatwoods salamander breeding within each wetland. Chapter 2 focused on flatwoods salamander phenology (the timing of life history events) in response to climate change. I quantified flatwoods salamander movements into and out of breeding wetlands over a 10-year period (2010–2020), identifying temperature and precipitation patterns that were conducive to salamander movements. I then used future climate projections to forecast movement opportunities for flatwoods salamander from 2030–2099 and used an existing hydrologic model built on the same climate data to understand how phenology may interact with hydrology. Overall, only a small number of years are likely to have an ideal intersection of phenology and hydrology as has been observed during recent breeding seasons. Chapter 3 described the construction of a stochastic Integral Projection Model for flatwoods salamanders. I integrated the projections from Chapter 2 with the population model to estimate the viability of two flatwoods salamander populations from 2030–2099 under multiple climate change scenarios. The results indicated that approximately half of the examined scenarios resulted in a high probability (>0.5) of extinction when considering both wetland hydrology and salamander phenology. In Chapter 4, I described the creation of a stochastic Integral Projection Model for indigo snakes. I then demonstrated the utility of this model by examining the effects of initial population size, road density, and removal of individuals to support a captive colony on indigo snake populations. I found that high road densities and high collection rates would likely lead to population declines, although the rate of declines and extinction risk varied across scenarios. Taken together, these projects highlight some of the challenges currently facing herpetofauna in the southeastern United States, demonstrate the difficulty in conserving these often-overlooked species, and provide useful tools for ongoing conservation efforts focusing on these two imperiled species. / Doctor of Philosophy / We are in the midst of a global biodiversity crisis, with rates of species extinction far exceeding normal levels. Species loss is largely driven by global change attributable to human activities. A rapidly changing world can make it challenging to effectively conserve and manage imperiled species. In this work, I studied two species found only in the southeastern United States that are listed on the U.S. Endangered Species List. Chapters 1–3 focused on the Reticulated Flatwoods Salamander (Ambystoma bishopi), while Chapter 4 focused on the Eastern Indigo Snake (Drymarchon couperi). In Chapter 1, I used high resolution elevation data to map the shape of flatwoods salamander breeding wetlands. These data were then used to estimate flooded areas across multiple years. Flooded area metrics were combined with vegetation measurements to map potential flatwoods salamander breeding habitat. In Chapter 2, I examined how flatwoods salamander movements may respond to climate change. I identified time periods and weather conditions that coincided with flatwoods salamander movements into and out of breeding wetlands. I then projected potential movement opportunities based on multiple future climate scenarios for each breeding season from 2030–2099. My results showed that few years are likely to be ideal for flatwoods salamander reproduction, which is similar to trends observed in recent years. In Chapter 3, I built a population model for flatwoods salamanders. I then combined the model with predictions made in Chapter 2 to estimate the probability that populations would go extinct by the end of the century. The results indicated that the two flatwoods salamander populations examined had a high probability (>0.5) of extinction in about 50% of the climate scenarios. In Chapter 4, I constructed a population model for indigo snakes using a variety of available data. I used this model to examine the effects of road density, initial population size, and removal of individuals to support a captive colony on indigo snake populations. The results suggested that populations experiencing high road densities or high collection rates were likely to decline over time. These projects highlight some of the difficulties in conserving often-overlooked reptiles and amphibians in the southeastern United States and provide important tools for ongoing conservation projects working with these two imperiled species.

Metal contamination is a considerable environmental problem because metals are persistent contaminants. Ion exchange is one of the most commonly used treatment options for trace metal removal. This research develops and evaluates a redox active modified ion exchange system that has the potential to reduce the ionic strength of ion exchange regeneration streams. Poly-L-cysteine (PLC) was selected as the redox active, adsorbing functional group on the surface of a reticulated vitreous carbon (RVC) electrode. PLC is an excellent soft acid metal chelator and is unique in that its thiol groups can form disulfide bonds with each other. The reduction of available thiols changes the metal binding capacity of the peptide since the thiol is the primary binding group. RVC provides a macroporous conductive monolithic resin to support the peptide. An experimental apparatus was designed to study the properties of this system and estimate performance. Distinct oxidized and reduced states of PLC on the surface of the RVC were confirmed by changes in metal binding characteristics. Adsorption edges showed a sharper pH dependence for the reduced electrode compared to the oxidized electrode from pH 3-7. Adsorption isotherms performed at pH 7 showed increased capacity for the reduced electrode. The change was reversible by chemical and electrical reduction. This difference was confirmed at the molecular level with Cd- EXAFS of oxidized and reduced electrodes. A greater degree of cadmium-sulfur coordination was observed on the reduced electrode and a greater cadmium-oxygen coordination was apparant on an oxidized electrode. A multidentate adsorption model was developed to model the pH dependent behavior of cadmium adsorption on the PLC-RVC surface. Nickel adsorption showed increased adsorption in the oxidized state. The most likely explanation is increased carboxylate complexation. The electronically switchable ion exchange system (ESIE) provides a framework for modifying traditional ion exchange processes. The system has 5 to 10 times less specifc capacity than current ion exchange systems, but uses solutions 10-100 times lower in ionic strength for regeneration. Further studies on the effect of ionic strength on adsorption and current usage are necessary to compare the cost of the ESIE process to traditional ion exchange. / text

Globally, amphibian species have been in decline and a wide range of factors have been purported to be driving the decline. The Gulf Coastal Plain of Florida has a high degree of endemism and rarity and the biodiversity in the region includes a diverse suite of amphibian species. Degradation of habitat has been considered by many to be a major part of amphibian declines, however amphibian declines are complex and in many cases multiple factors are occurring in concert. My dissertation research examined aspects of habitat ecology and occupancy for two rare amphibians, Florida Bog Frog (Rana okaloosae) (Chapter 1, 2, and 3) and Reticulated Flatwoods Salamander (Ambystoma bishopi) (Chapter 5), that are both restricted to the Northern Gulf Coastal Plain. Further, for R. okaloosae I examined the influence of a sympatric congener, Bronze Frog (R. clamitans clamitans), on microhabitat selection (Chapter 1) and growth of tadpoles (Chapter 4). My overall goal was to be able to elucidate factors that limit the geographic range of R. okaloosae and A. bishopi and to identify habitat characteristics that managers could maintain or create to conserve or increase populations of these species. My first chapter examined the microhabitat relationships between R. okaloosae and R. c. clamitans. Rana okaloosae is endemic to northwestern Florida and is sympatric with R. c. clamitans, a more common and widely distributed congener. Further, the two species appeared to be syntopic, have overlapping breeding seasons, and are known to hybridize. The objectives of this chapter were to assess the microhabitat selection of both species and to assess differences in microhabitat use of males of both species during the breeding season. My modeling of habitat selection and comparison of variables used by each species suggests that males of these species select different resources when calling. Therefore, these sympatric ranids select for different resources at a fine scale, however there does appear to be some overlap among some selected habitat characteristics. In Chapter 2, I assessed the habitat use of R. okaloosae at multiple spatial scales. I surveyed for R. okaloosae and evaluated habitat characteristics at used sites and sites where I had no detections to develop among- and within-stream habitat models for R. okaloosae. Rana okaloosae used habitats with high amounts of emergent vegetation at both the among-stream scale and the within-stream scale. Emergent vegetation appears frequently in models of anuran habitat selection, particularly those that occur in fire-dominated landscapes. Further understanding the habitat requirements of R. okaloosae will allow land managers to use appropriate management activities (e.g., prescribed fire) that will increase emergent vegetation and potentially restore habitat that may help increase populations of R. okaloosae. In Chapter 3, I conducted aural surveys for R. okaloosae at two different spatial scales: range-wide and stream-level scales to understand how occupancy and colonization of R. okaloosae may be influenced by scale. My results suggest that at both spatial scales occupancy of R. okaloosae was best described by the presence of mixed forest wetlands at survey sites. At the range-wide scale, colonization and detection were constant across years, however, at the stream-level scale, colonization was predicted by the number of years since last fire and detection was best predicted by the additive combination of relative humidity and temperature. Occupancy of R. okaloosae was patchy at the range-wide and at the stream-level scales and colonization was low at both scales, while derived estimates of local extinction were moderately high. While R. okaloosae still occur in 3 watersheds where they were initially observed in the 1980's, one of the three watersheds appears to be very isolated and detections there are becoming very infrequent. In Chapter 4, I experimentally evaluated the effects of R. c. clamitans tadpoles on R. okaloosae tadpoles. My results suggest that there was limited influence of R. c. clamitans on R. okaloosae. Conversely, it appeared that Rana c. clamitans was more susceptible to intraspecific competition than interspecific competition. The lack of a strong competitive effect of Rana c. clamitans on Rana okaloosae suggests that competitive interactions among tadpoles may have a limited effect at the densities I examined. In Chapter 5, our objectives were to evaluate a suite of within-pool factors (i.e., vegetation structure, water level, and an index to presence of fish) that could influence occupancy of breeding wetlands by larval flatwoods salamanders on Eglin Air Force Base in Florida, USA. Site occupancy over a 4 year period was best described by a model that incorporated high herbaceous vegetation cover and open canopy cover. Detection probability was assessed, but it varied among years and was not included in the model. Our study suggests that managing the breeding habitat of flatwoods salamander for open canopies and dense herbaceous vegetation may contribute to this species' recovery. In conclusion, Chapters 1-3 of my dissertation contribute to a growing understanding about the habitat ecology of R. okaloosae. I have evaluated habitat use of R. okaloosae at multiple spatial scales. At the finest spatial scale R. okaloosae selected for sites that had an abundance of cover probably decreasing their risk of predation (Chapter 1). Similarly, in Chapter 2 at two spatial scales, among and within-streams, R. okaloosae selected for emergent vegetation. Finally, at the broadest spatial scale, range-wide, R. okaloosae were found to be associated with mixed forest wetlands (Chapter 3). I did not find strong support for competition between R. okaloosae and R. c. clamitans tadpoles, although there was some evidence of asymmetric competition (Chapter 4). Further, adult males of each species did not select the same habitat characteristics for calling sites, so there appeared to be some resource partitioning (Chapter 1). Finally, the presence of A. bishopi larvae was found to be associated with herbaceous vegetation and moderate amounts of canopy cover (Chapter 5). Results from Chapter 2 and 5 suggest that both R. okaloosae and A. bishopi are associated with habitat conditions that are likely a result of fire penetrating wetland areas. / Ph. D.

A investigação aqui realizada examina o papel que os valores cognitivos e nãocognitivos desempenham nas práticas científicas. Essa análise fundamenta-se em uma comparação entre os modelos propostos por Hugh Lacey e por Larry Laudan para explicar a dinâmica da atividade científica. Veremos que, no modelo desenvolvido por Lacey, cuja idéia central reside nas estratégias de pesquisa, ambos os tipos de valor possuem papéis legítimos na atividade científica. Já no modelo reticulado, proposto por Laudan, o autor admite apenas os valores cognitivos como constituintes da racionalidade científica. A partir de uma comparação entre ambos os modelos, pretendemos mostrar que o modelo de Lacey parece ser mais abrangente do que o modelo reticulado, na medida em que este último poderia ser considerado como uma parte do primeiro. / The present investigation examines the role of cognitive and non-cognitive values in scientific practices. This analysis is based on a comparison between the models proposed by Hugh Lacey and Larry Laudan to explain the dynamics of scientific activity. We will see that in Laceys model, whose main idea are the strategies of investigation, both kinds of values have legitimate roles in scientific activity. In the reticulated model, proposed by Laudan, the author admits only cognitive values as constitutive of scientific rationality. Based on a comparison between both models, we will try to show that Laceys model seems broader than the reticulated model, in the sense that the reticulated one could be considered as a part of Laceys model.