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1
JR, MARCOS AURELIO PINTO MARZANO. "ROBOTIC SYSTEM FOR MONITORING WATER QUALITY IN LENTIC ENVIRONMENTS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36947@1.
Full textAbstract:
PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
Nas últimas décadas, a crescente conscientização ambiental levou ao reconhecimento da necessidade do uso responsável dos recursos hídricos. Para garantir isso, a boa gestão de reservatórios hídricos requer um monitoramento ambiental adequado, com medições confiáveis dos parâmetros de qualidade da água em vários pontos do reservatório, permitindo o controle da qualidade da água e seus impactos na fauna, flora e comunidades ribeirinhas dos reservatórios. O monitoramento das variáveis ambientais dos reservatórios é atualmente realizado por processo tradicional de coleta manual. Infelizmente, no Brasil, as iniciativas de produzir um sistema robótico aquático com tecnologia nacional e de baixo custo, quando comparado a equivalentes importados, são ainda raras e se restringem a algumas poucas instituições acadêmicas, não tendo sido localizado nenhum fabricante comercial deste tipo de veículo no país. Visando preencher esta lacuna, o presente trabalho teve como objetivo o desenvolvimento do protótipo de um sistema robótico aquático capaz de se locomover autonomamente em lagoas, lagos e reservatórios, coletando informações físico-químicas da água e armazenando estes dados na memória. Além disso, foi incluído no protótipo uma câmera de vídeo, sistema de iluminação e um sistema de controle remoto, objetivando o controle pela equipe em terra. Nos testes realizados em dias ensolarados e chuvosos, o robô apresentou boa dirigibilidade, estabilidade e manobrabilidade. O vaso de pressão do sistema robótico resistiu às pressões necessárias durante os testes, a eletrônica conseguiu atender as especificações de projeto e o software conseguiu estabelecer um controle de navegação, cumprindo o trajeto de uma rota estabelecida.
In recent decades, the growing environmental awareness has led to the recognition of the need for responsible use of water resources. To ensure this, the good management of water reservoirs requires adequate environmental monitoring, with reliable measurements of water quality parameters in various parts of the reservoir, allowing the control of water quality and its impacts on fauna, flora and riverine communities of the reservoirs. Monitoring environmental variables of the reservoirs is currently performed by traditional process of manual collection. Unfortunately, in Brazil, initiatives to produce a water robotic system with national and low cost technology, compared to imported equivalents, are still rare and restricted to a few academic institutions, and no commercial manufacturer of this type of vehicle was found in the country. Aiming to fill this gap, the main objective of this study was to develop a prototype of a water robotic system capable of autonomously navigate in ponds, lakes and reservoirs, collecting physicochemical information of water and storing this data in memory. Moreover, a video camera, illumination and a remote control system were included in the prototype, allowing the team on the ground to control the prototype. In tests conducted in sunny and rainy days, the robot presented good handling, stability and maneuverability. The robotic system pressure vessel resisted pressures required during testing, the electronics met the design specifications and the software was able to establish a navigation control, fulfilling the path of an established route.
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Wood, Sylvia Louise Rebecca. "Tadpole - sediment interactions of the western toad, Bufo boreas, in a temperate-lentic system." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/32200.
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Sediment and nutrient loading in freshwater systems are leading causes of aquatic habitat degradation in North America. The impacts of fine-sediment and nutrient additions on the growth and survival of Bufo boreas tadpoles and emergent metamorphs was investigated in mesocosm and exclosure experiments. Mesocosm tanks received weekly pulses of fine, organic-rich (8% -9%) sediments to create initial concentrations of 0, 130 and 260 mg/L of sediment and bi-weekly additions of nutrients (N-160 μg/L, P-10 μg/L) in a factorial design. Within mesocosms, tadpole exclosures allowed for quantification of tadpole grazing pressure on periphyton biomass, chlorophyll α and sediment deposition. Tadpoles receiving sediment additions experienced slower growth rates and reduced survival to metamorphosis, though no effects of treatment were detected on metamorphic size or timing. Nutrient additions also lowered survival, but had no impact on other measured parameters. Dissections and gut content analysis revealed that tadpoles ingested sediment in large quantities and scanning electron microscopy showed particles were also found in their gill tissues. Together these results suggest that though organic-rich sediments were readily consumed, tadpoles derived little or no net benefit from these materials. Measures from tiles within the exclosures in the mesocosm experiment demonstrated that tadpoles were able to reduce the standing stocks of periphyton by 35-80% and to clear virtually 100% of all deposited sediment from grazing surfaces. Sediment clearing activities via ingestion acted to restructure the benthic abiotic habitat, but at tadpole densities used in the experiment did not have a beneficial effect on underlying periphyton growth. Under natural conditions, such grazing pressure and sediment removal activities could lead to changes in the algal community and consequent shifts in invertebrate grazers. Together, these results highlight a potential role for Bufo boreas tadpoles as ecosystem engineers in temperate pond habitats.Forestry, Faculty of
Graduate
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Tabor, Roger Allen. "The Importance of Cover for Juvenile Rainbow Trout in Lentic Systems: Field Observations and an Experimental Study on Predation." DigitalCommons@USU, 1990. https://digitalcommons.usu.edu/etd/6487.
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Juvenile rainbow trout Oncorhynchus mykiss stocked into mid-elevation reservoirs in Utah are vulnerable to predation from piscivorous fish and birds. I determined how effectively juvenile trout used cover to avoid these predators by (1) direct observations (snorkel transects) of habitat selection in two reservoirs and (2) measurements of survival and growth rates in a pond experiment where adult brown trout Salmo trutta were predators. Observations of juvenile trout were conducted within five weeks of stocking in 1988 and 1989. During the day, juvenile trout were abundant in complex inshore habitats and avoided simple habitats such as sand and gravel. Measurements of gut fullness indicated that juvenile trout fed during the day but not during the night. Large Daphnia comprised more than 95% of the diet of juvenile trout. Because large Daphnia were often higher offshore than inshore in both reservoirs, selection of inshore cover is believed to be primarily a response to reduce predation risk. At night, trout in both reservoirs selected more exposed areas and rested on the bottom. In the pond experiment, the presence of brown trout significantly increased mortality of juvenile trout, decreased their growth rates, and caused them to avoid offshore areas. The presence of cover significantly decreased predation rates but did not affect growth of the juvenile trout.
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Secretti, Elisangela. "DIVERSIDADE E DISTRIBUIÇÃO ESPACIAL DE COMUNIDADES DE MACROINVERTEBRADOS AQUÁTICOS EM ARROZAIS IRRIGADOS DE DUAS REGIÕES GEOMORFOLÓGICAS NO SUL DO BRASIL." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/5333.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorWide spatial scales of analysis in studies conducted in natural wetlands tend to present the greatest contributions to the total diversity of aquatic macroinvertebrates, because they include macrovariables such as hydrographic basins and different types of aquatic systems. However, for agroecosystems such as rice fields (usually converted wetlands), the knowledge on the variation of these communities diversity along wide spatial scales is still scarce, therefore hindering conservationist actions. In this study, aquatic macroinvertebrate communities were sampled in January 2012 in irrigated rice fields from two geomorphological regions (Planície Costeira and Depressão Central), in southernmost Brazil (Rio Grande do Sul state). Four hierarchical spatial scales of analysis sample, rice field, rice area and geomorphological region were analyzed through the additive partitioning of diversity method. Estimated richness was similar between the studied geomorphological regions and rice areas. However, composition and, specially, dominant and indicator taxa varied between regions, mainly in the wider scales of analysis (regions and rice areas). Mean values of variables such as pH, dissolved oxygen, electrical conductivity and water temperature had greater variation between rice areas, influencing differences between communities in this scale. Differences in accumulated precipitation and mean air temperature between geomorphological regions had strong influence on communities variation. The additive partitioning method showed that the diversity variation was significantly higher than the expected by chance in among rice areas (β3) and among geomorphological regions (β4) scales. However, the percentual contribution of these scales for total diversity (γ) was lower than that of among rice fields scale (β2), due to the influence of differences in management practices and growth stages of the rice plant on macroinvertebrate communties. Although climatic differences strongly affected macroinvertebrate community structure from different geomorphological regions, the enviromental homogeneization and simplification promoted by this agroecosystem interfered in community diversity variation at regional scale. In general, differentiated management practices for each rice field were the most determinant factors for the diversity and special distribution of the aquatic macroinvertebrates communities.
Em áreas úmidas naturais, escalas espaciais mais amplas de análise, que abarcam macrovariáveis como bacia hidrográfica e tipo de sistema aquático, tendem a apresentar as maiores contribuições para a diversidade total das comunidades aquáticas. Contudo, em agroecossistemas como arrozais (usualmente áreas úmidas convertidas), o conhecimento sobre a variação da diversidade destas comunidades ao longo de amplas escalas espaciais ainda é escasso e pouco compreendido, prejudicando ações conservacionistas. No presente estudo, comunidades de macroinvertebrados aquáticos foram amostrados, em janeiro de 2012, em arrozais irrigados de duas regiões geomorfológicas (Planície Costeira e Depressão Central), no extremo sul do Brasil (estado do Rio Grande do Sul). Quatro escalas espaciais hierarquizadas - em ordem crescente: amostra, arrozal, área e região geomorfológica - foram utilizadas para análise. A riqueza estimada foi similar entre regiões geomorfológicas e áreas estudadas, contudo a composição e, especialmente, os táxons dominantes e indicadores variaram entre as regiões, principalmente na maior escala. Valores médios de variáveis como pH, oxigênio dissolvido, condutividade elétrica e temperatura da água variaram mais entre as áreas de estudo, influenciando diferenças entre as comunidades nesta escala. Diferenças nos valores de precipitação acumulada e temperatura média do ar nas duas regiões tiveram forte influência nas variações das comunidades. O método da partição aditiva mostrou que a variação da diversidade foi significativamente maior do que o esperado ao acaso nas escalas entre áreas de arrozais (β3) e entre regiões geomorfológicas (β4). Contudo, a contribuição percentual de ambas para a diversidade total observada (γ) foi menor do o que a de escala entre arrozais (β2), devido à influência de diferenças de técnicas de manejo e estágios de crescimento dos arrozais sobre as comunidades de macroinvertebrados. Embora as diferenças climáticas das regiões afetem intensamente a estrutura das comunidades de macroinvetebrados em arrozais de diferentes regiões geomorfológicas, a homogeneização e simplificação ambiental desse agroecossistema interferiu na variação da diversidade das comunidades em escala regional. De forma geral, as práticas de manejo diferenciadas de cada arrozal foram os fatores mais determinantes para a diversidade e distribuição espacial das comunidades de macroinvertebrados aquáticos.
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Sandy, Alexis Emily. "Environmental and Digital Data Analysis of the National Wetlands Inventory (NWI) Landscape Position Classification System." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/33572.
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The National Wetlands Inventory (NWI) is the definitive source for wetland resources in the United States. The NWI production unit in Hadley, MA has begun to upgrade their digital map database, integrating descriptors for assessment of wetland functions. Updating is conducted manually and some automation is needed to increase production and efficiency. This study assigned landscape position descriptor codes to NWI wetland polygons and correlated polygon environmental properties with public domain terrain, soils, hydrology, and vegetation data within the Coastal Plain of Virginia. Environmental properties were applied to a non-metric multidimensional scaling technique to identify similarities within individual landscape positions based on wetland plant indicators, primary and secondary hydrology indicators, and field indicators of hydric soils. Individual NWI landscape position classes were linked to field-validated environmental properties. Measures provided by this analysis indicated that wetland plant occurrence and wetland plant status obtained a stress value of 0.136 (Kruskalâ s stress measure = poor), which is a poor indicator when determining correlation among wetland environmental properties. This is due principally to the highly-variable plant distribution and wetland plant status found among the field-validated sites. Primary and secondary hydrology indicators obtained a stress rating of 0.097 (Kruskalâ s stress measure = good) for correlation. The hydrology indicators measured in this analysis had a high level of correlation with all NWI landscape position classes due the common occurrence of at least one primary hydrology indicator in all field validated wetlands. The secondary indicators had an increased accuracy in landscape position discrimination over the primary indicators because they were less ubiquitous. Hydric soil characteristics listed in the 1987 Manual and NTCHS field indicators of hydric soils proved to be a relatively poor indicator, based on Kruskalâ s stress measure of 0.117, for contrasting landscape position classes because the same values occurred across all classes.
The six NWI fieldâ validated landscape position classes used in this study were then further applied in a public domain digital data analysis. Mean pixel attribute values extracted from the 180 field-validated wetlands were analyzed using cluster analysis. The percent hydric soil component displayed the greatest variance when compared to elevation and slope curvature, streamflow and waterbody, Cowardin classification, and wetland vegetation type. Limitations of the soil survey data included: variable date of acquisition, small scale compared to wetland size, and variable quality. Flow had limitations related to its linear attributes, therefore is often found insignificant when evaluating pixel values that are mean of selected pixels across of wetland landscape position polygons. NLCD data limitations included poor quality resolution (large pixel size) and variable classification of cover types. The three sources of information that would improve wetland mapping and modeling the subtle changes in elevation and slope curvature that characterize wetland landscapes are: recent high resolution leaf-off aerial photography, high-quality soil survey data, and high-resolution elevation data.
Due to the data limitations and the choice of variables used in this study, development of models and rules that clearly separate the six different landscape positions was not possible, and thus automation of coding could not be attempted.Master of Science
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Kamci, Hamdi. "Optimisation Of Agrobacterium Mediated Gene Transfer And Micrografting Systems In Lentil (lens Culinaris Medik)." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/2/12605460/index.pdf.
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In this work Agrobacterium (KYRT1::pTJK136) mediated gene transfer to lentil (Lens culinaris Medik.) embriyo apex and regeneration through micro-grafting in lentil was studied.
In micro-grafting two different types root stock stem height and root stock preparations were optimized. According to the results half stem length was found to be more successful then the full. Also lentil root stock was more successful then the chickpea root stock. The types of root stock preparations studied were designated as Z and M. The Z type root stock was superior then the M type, when the micro-grafting, hardening and green-house stages were concerned.
In study of Agrobacterium mediated gene transfer to lentil embryo apex the effect of the following parameters on the transformation efficiency were addressedtype and intensity of injury, type of pre-incubation media for injured explants, effect of evacuation, effect of L-cysteine during co-cultivation and Agrobacterium incubation duration. According to the results crushing type of injury was superior over the poking and sonication type of injuries. Following the injury Hogland`s solution was used as pre-incubation media prior to infection. The effect of evacuation parameter was found to be insignificant whereas the effect of L-cysteine during co-cultivation was negative on the transformation efficiency. According to the Agrobacterium incubation duration studies, 240 minutes, followed by 120 minutes of Agrobacterium incubation were the most efficient in terms of transformation efficiency. However, since there was no significant difference among the two 120 minutes chosen to be the optimum bacterial incubation duration.
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Bayrac, Abdullah Tahir. "Optimization Of A Regeneration And Transformation System For Lentil (lens Culinaris M., Cv. Sultan-i) Cotyledonary Petioles And Epicotyls." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/3/12605453/index.pdf.
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In this study, optimization of a transformation and regeneration system via indirect organogenesis in cotyledonary petiole tissue of lentil (Lens culinaris Medik.) was investigated. Eight different medium types differing in their plant growth regulator compositions were employed to examine the callus induction potency of cotyledonary petiole. Except two, all other tested medium yielded more than 80% callus induction. Nine different medium types were studied to test the potencies of callus structures for shoot induction. Only the callus induced in medium H (1 mg/L Zeatin riboside + 1 mg/L Naphthalane acetic acid) yielded shoots at 8 to 40 % frequency. The most responsive medium was MS basal medium with no growth regulators. Also five and three different medium types were employed to examine callus induction potency of epicotyl tissues respectively. Each medium type yielded 90% callus induction. Only the callus induced in medium H yielded shoots At 6 to 26% frequency.
Preliminary studies were carried out for somatic embryogenesis in cotyledonary petiole. Effects of salicylic acid on somatic embryogenesis were also investigated. Salicylic acid at 200µM was found to enhance the percentage of somatic embryos by 25 % and reduce the necrosis 24 %. However none of the globular and heart shape embryos were able to regenerate. Transient GUS expression efficiencies of roots, shoot tips, and cotyledonary petioles were tested after Agrobacterium-mediated transformation. Transformation frequencies were 26, 74, and 38 % for cotyledonary petiole, shoot tips, and roots respectively.
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Barros, Lilian Rodolfo. "The Trophic state index and its adaptation to the lentics systems present in Cearà semiarid." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=11376.
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Para suprir a carÃncia hÃdrica, o Cearà dispÃe de uma grande rede de reservatÃrios artificiais destinados aos mais diversos usos. PorÃm, Ãguas que permanecem reservadas em aÃudes sÃo limnolÃgicamente vulnerÃveis, sendo o fenÃmeno da eutrofizaÃÃo uma das piores consequÃncias resultantes das atividades antrÃpicas desenvolvidas nas Ãreas de contribuiÃÃo desses reservatÃrios, consequÃncias essas que sÃo agravadas ainda mais em funÃÃo das caracterÃsticas naturais do semiÃrido, um ambiente marcado por baixas precipitaÃÃes pluviomÃtricas e pela
sua mà distribuiÃÃo no espaÃo e no tempo. Para auxiliar no estudo trÃfico dessas Ãguas, hà muito vem sendo utilizada pelos limnÃlogos uma ferramenta destinada a classificar os recursos hÃdricos no tocante ao seu estado de trofia, o IET - Ãndice do
Estado TrÃfico, desenvolvido por Carlson (1977).
A pesquisa aqui desenvolvida consistiu em aprimorar o estudo da correlaÃÃo entre os parÃmetros de Clorofila a, fÃsforo total e TransparÃncia de Secchi, utilizados na composiÃÃo do IET, bem como ajustar a escala logaritmica do Ãndice, basaeando-se
nas medidas mÃnimas e mÃximas de Secchi para os reservatÃrios de Ãgua do CearÃ, o que resultou em uma metodologia de classificaÃÃo trÃfica adaptada Ãs condiÃÃes dos sistemas lÃnticos inseridos no semiÃrido cearense.To meet the water shortage, Cearà has an extensive network of artificial reservoirs intended for various uses. However, waters that remain reserved in dams present limnological vulnerability, and the phenomenon of eutrophication is one of the worst consequences of anthropic activities developed in the areas of contribution of these reservoirs, consequences that are aggravated due to the natural characteristics of semiarid, an environment marked by low rainfall and its poor distribution in space and time. To assist the trophic study of these waters, it has long been used by limnologists a tool to classify water resources in relation to their trophic state, the TSI - the Trophic State Index, developed by Carlson (1977). The research conducted here was to enhance the study of the correlation among the parameters of chlorophyll a, total phosphorus, and Secchi Transparency, used in the composition of the TSI, as well as to adjust the logarithmic scale of the index, according to Secchi's maximum and mi nimum measures to the water reservoirs of CearÃ, which resulted in a trophic classification methodology adapted to the conditions of the inserted lentic systems in Cearà semiarid
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Ercan, Oya. "Effect Of Drought And Salt Stresses On Antioxidant Defense System And Physiology Of Lentil (lens Culinaris M.) Seedlings." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609250/index.pdf.
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In this study, 14 days old lentil seedlings (Lens culinaris Medik cv. Sultan), which were subjected to 7 days of drought (20% PEG 6000), and salt (150 mM NaCl ) stress , were examined in a comparative manner for the effects of drought and salt stress treatments. In shoot and root tissues physiological parameters such as wet-dry weight, relative water content, root-shoot lengths, membrane electrolyte leakage, and lipid peroxidation in terms of malondialdehyde (MDA) were determined. H2O2 content, proline accumulation and chlorophyll fluorescence analysis were also performed. Changes in the activity of antioxidant enzymes such as superoxide dismutase (SOD: EC 1.15.1.1), catalase (CAT: EC 1.11.1.6) ascorbate peroxidase (APX: EC 1.11.1.11) and glutathione reductase (GR: EC 1.6.4.2) were observed upon stress treatments. In salt treated lentil seedlings, significant decreases in wet-dry weight, RWC, shoot-root length and chlorophyll fluorescence measurements indicated a sensitivity, when compared to drought treated plants. Higher MDA concentration and higher electrolyte leakage amounts are supported these results. APX, GR and proline seem to play important roles in antioxidant defense against salt stress for both tissues by removing reactive oxygen species and protecting macromolecules and membranes. GR and proline are also maintains the main protective mechanism against drought stress effects. SOD is active in drought stressed roots and salt stressed shoots, where the H2O2 contents are also observed to be increased.
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Cicerali, Isin Nur. "Effect Of Salt Stress On Antioxidant Defense Systems Of Sensitive And Resistant Cultivars Of Lentil (lens Culinaris M.)." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/3/12605248/index.pdf.
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ABSTRACT
EFFECT OF SALT STRESS ON ANTIOXIDANT DEFENSE SYSTEMS OF
SENSITIVE AND RESISTANT CULTIVARS OF LENTIL
Cicerali, Iin Nur
M.Sc., Department of Biotechnology
Supervisor: Prof. Dr. Meral Yücel Co-supervisor: Asst. Prof. Dr. Fü
sun (nci) Eyidoan June 2004, 90 pages In this study, two lentil cultivars (Lens culinaris, Medik.) (ILL5582-salt tolerant and ILL590) were characterized and compared due to their NaCl susceptibility and antioxidant mechanism was examined under laboratory conditions. Physiological parameters such as wet-dry weight, root-shoot lengths, cell membrane stability, lipid peroxidation in terms of malondialdehyde (MDA), H2O2, proline contents were determined. The activities of antioxidant enzymes such as superoxide dismutase (SOD: EC 1.15.1.1), catalase (CAT: EC 1.11.1.6), ascorbate peroxidase (APX: EC 1.11.1.11) and glutathione reductase (GR: EC 1.6.4.2) were examined and analyzed in 14 days old plant seedlings after 9 days of normal growth and 5 days of 100mM and 200mM NaCl stress conditions. Shoot-root length and wet-dry weight percent decrease were more in ILL590. Especially shoot tissues were affected more from the stress conditions when compared to root tissues. ii According to malondialdehyde (MDA) content and membrane stability results, lipid peoxidation was higher in ILL590 and significant increases were observed in shoot tissues. Proline concentration showed a remarkable increase in salt concentration dependent manner. Higher concentrations of proline in ILL5582 might be the reason of higher salt tolerance when compared to ILL590. Among the antioxidant enzymes SOD was the one which showed highest activity increase. At organ level roots showed highest activity when compared to leaves. In the organelle higher activity percent contribution was achieved by cytosolic Cu/ZnSOD isozyme. Higher percent increase of this isozyme was observed in ILL5582. This might be one of the tolerance mechanisms that get activated against NaCl stress. APX activity showed similar alterations in both cultivars. In leaf tissues significant increase was observed but in root tissues ascorbate peroxidase activity did not change significantly. Glutathione Reductase activity increase was significant in both cultivars leaf tissues but although ILL5582 showed a stress concentration dependent increase, ILL590 did not. The activity of CAT enzyme in leaf and root tissues of both cultivars did not significantly change under increasing salt stress conditions. The results suggested that the leaves were more susceptible to salt stress. Also when two cultivars were compared ILL5582 was found to be more tolerant against salt stress than ILL590 under laboratory conditions and SOD enzyme seemed to be the most active component of the salt tolerant mechanism.
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Brandt, Ivan Scherole [UNESP]. "Características de sistemas de transmissão tetrafásicos submetidos a transitórios lentos e rápidos." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/87111.
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Entre tantas tecnologias alternativas desenvolvidas ao longo das últimas décadas, procurando aumentar a eficácia das técnicas convencionais ou propondo novas técnicas não convencionais na transmissão da energia elétrica a longas distâncias e lugares de difícil acesso, o estudo proposto apresenta alguns conceitos e características para sistemas de transmissão constituídos por quatro fases genéricas. O sistema de transmissão tetrafásico tem sido tema de diversos estudos e aplicações em alguns países da Europa e Ásia, apresentando algumas vantagens quando comparado ao sistema de transmissão trifásico convencional. Esse sistema pode ser facilmente integrado ao sistema trifásico por meio de transformadores, amplamente abordado por diversas referências bibliográficas. Nesse estudo foi realizado uma análise comparativa das possíveis sobretensões ocorridas nos domínios da frequência e do tempo entre os sistemas de transmissão trifásico e tetrafásico, avaliando as características elétricas e as respostas transitórias eletromagnética e impulsiva, mostrando novas vantagens sobre esta tecnologia, fornecendo uma avaliação completa sobre o tema
Among the many alternative technologies developed over the past decades, seeking to increase the effectiveness of conventional techniques or proposing new non-conventional techniques in the transmission of electricity over long distances and places of difficult access, the proposed study presents some concepts and features to transmission systems that are constituted of four generic phases. The four-phase transmission system has been subject of numerous studies and applications in some countries in Europe and Asia, presenting some advantages compared to the conventional three-phase transmission system. This system can be easily integrated into the three-phase system through transformers, thoroughly approached by several bibliographical references. In this study was made a comparative analysis of the possible overvoltages that occurred in the areas of frequency and time between the transmission systems of three-phase and four-phase, evaluating the electrical characteristics and the transient answers, electromagnetic and impulsive, showing new advantages over this technology, providing a complete evaluation of this issue
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Brandt, Ivan Scherole. "Características de sistemas de transmissão tetrafásicos submetidos a transitórios lentos e rápidos /." Ilha Solteira : [s.n.], 2012. http://hdl.handle.net/11449/87111.
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Orientador: Sérgio KurokawaBanca: Jean Marcos de Souza Ribeiro
Banca: Edson Guedes da Costa
Resumo: Entre tantas tecnologias alternativas desenvolvidas ao longo das últimas décadas, procurando aumentar a eficácia das técnicas convencionais ou propondo novas técnicas não convencionais na transmissão da energia elétrica a longas distâncias e lugares de difícil acesso, o estudo proposto apresenta alguns conceitos e características para sistemas de transmissão constituídos por quatro fases genéricas. O sistema de transmissão tetrafásico tem sido tema de diversos estudos e aplicações em alguns países da Europa e Ásia, apresentando algumas vantagens quando comparado ao sistema de transmissão trifásico convencional. Esse sistema pode ser facilmente integrado ao sistema trifásico por meio de transformadores, amplamente abordado por diversas referências bibliográficas. Nesse estudo foi realizado uma análise comparativa das possíveis sobretensões ocorridas nos domínios da frequência e do tempo entre os sistemas de transmissão trifásico e tetrafásico, avaliando as características elétricas e as respostas transitórias eletromagnética e impulsiva, mostrando novas vantagens sobre esta tecnologia, fornecendo uma avaliação completa sobre o tema
Abstract: Among the many alternative technologies developed over the past decades, seeking to increase the effectiveness of conventional techniques or proposing new non-conventional techniques in the transmission of electricity over long distances and places of difficult access, the proposed study presents some concepts and features to transmission systems that are constituted of four generic phases. The four-phase transmission system has been subject of numerous studies and applications in some countries in Europe and Asia, presenting some advantages compared to the conventional three-phase transmission system. This system can be easily integrated into the three-phase system through transformers, thoroughly approached by several bibliographical references. In this study was made a comparative analysis of the possible overvoltages that occurred in the areas of frequency and time between the transmission systems of three-phase and four-phase, evaluating the electrical characteristics and the transient answers, electromagnetic and impulsive, showing new advantages over this technology, providing a complete evaluation of this issue
Mestre
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Guimarães, Claudia. "Os diagramas do sistema de atendimento à infância: suas lentes punitivas." Universidade do Estado do Rio de Janeiro, 2014. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7726.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorO presente trabalho se propõe a colocar em análise as relações de três famílias pobres com o Sistema de Garantia de Direitos (SGD), as quais, por fim, tiveram o seu poder familiar destituído, sob a perspectiva da moralização, da disciplina, da vigilância e do controle. As tramas e os caminhos tortuosos, as práticas sociais punitivas e penais, as relações de verdades e os poderes que se exercem e se atualizam, as resistências e os jogos de tensões e forças que se apresentam, tudo isso está posto e descrito nas linhas desta pesquisa, à luz de autores clássicos como Foucault (principalmente), Deleuze, Guattari, Lourau, Nietzche, Donzelot, bem como contribuições mais próximas de autores nacionais, que se debruçam em estudos e pesquisas sobre os temas acima e dialogam com as situações em análise nesta pesquisa. Desnaturalizar os lugares constituídos à luz da moral, das produções subjetivas contemporâneas, dos costumes higienistas e correcionais, das tentativas de enquadramento das práticas familiares, de um jeito de ser pai e mãe, é um dos principais propósitos desta pesquisa. Trata-se de pensar e criar outras possibilidades, como um sopro de liberdade, de desconstrução de lugares, de outras perspectivas e práticas possíveis.
This dissertation proposes to put on analyzing the relations of three poor families with assurance system rights, which finally had their family power stripped from the perspective of ethical standards, discipline, surveillance and control. The plots and devious ways, punitive and criminal social practices, the relations of truth and the powers that are exercised and updated, the resistors and games of tensions and forces that arise, are all described in the lines and put this research, in the light of classical authors such as Foucault (mostly), Deleuze, Guattari, Lourau, Nietzche, Donzelot and closer to national authors contributions that focus on studies and research on the above topics, dialogue with situations analysis in this research. Denature the places made in the light of morality of the productions subjective and contemporary, hygienists and correctional customs, attempts framework of family practice, a way of being father and mother, is one of the main purposes of this research. It is think and create other possibilities, like a breath of freedom, of deconstruction of places, about other possible perspectives and practices.
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Wang, Lina [Verfasser], and Wilhelm [Akademischer Betreuer] Claupein. "Lentil production in Germany : testing different mixed cropping systems, sowing dates and weed controls / Lina Wang. Betreuer: Wilhelm Claupein." Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2012. http://d-nb.info/1027354211/34.
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Brambilla, Giovanni. "Dynamique lente de systèmes colloïdaux modèles." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20008/document.
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Ce travail est consacré à l'étude, par des techniques originales de diffusion dynamique de la lumière, de la dynamique lente de deux systèmes colloïdaux modèles. On a utilisée une technique de Corrélation Résolue dans le Temps (TRC) et des simulations numériques pour sonder, sur une grande plage de concentrations et sur sept décades en temps de relaxation, la dynamique d'un système de sphères dures colloïdales approchant de la transition vitreuse. A faible fraction volumique les temps de relaxation peuvent être représentés par une loi de puissance critique comme prévu par la Théorie de Couplage des Modes (MCT). A des concentrations élevées le temps de relaxation augmente selon une inattendue loi exponentielle critique avec une fraction volumique critique supérieure à celle prévue par MCT. L'étude des fluctuations de la dynamique confirme la présence d'un régime de dynamique activée: ce scénario est le même que l'on retrouve pour les systèmes vitreux moléculaires. Le deuxième sujet étudié est le comportement d'une suspension de colloïdes attractifs soumis à la contrainte gravitationnelle. Initialement, des agrégats de particules sédimentent en formant un gel sur le fond de la cellule. Les techniques spéciales employées nous ont permis de mesurer l'évolution des profils de concentration, des profils de vitesse et la dynamique locale dans la phase gel: la sédimentation peut être complètement décrite par le taux de déformation locale qui permet aussi une remise à l'échelle de la dynamique locale. Le rôle de la friction aux parois des cellules a été sondé par des expériences de polarimétrie et par la résolution numérique d'un modèle poroélastique pour la sédimentation du gelWe investigated, using original light scattering techniques, the slow dynamics of two different model colloidal systems. We used a Time Resolved Correlation (TRC) technique and numerical simulations to study the dynamics of systems of colloidal hard spheres over a broad range of densities and seven decades in relaxation time. At low volume fraction the equilibrium relaxation time is described by the algebraic divergence predicted by mode-coupling theory (MCT). At higher density the relaxation time increases with an unexpected critical exponential form, whose the critical volume fraction is much larger then the MCT singularity. The fluctuations of the dynamics confirm the presence of an activated regime, as founded in molecular glass formers close to the glass transition. The second research subject concerns the behaviour of suspensions of attractive colloidal particles under gravitational stress. Initially, clusters fall forming a gelled deposit at the cell bottom. Our apparatus allows us to follow over time the concentration profile, the velocity profile and the local dynamics in the gel phase: the settling may be fully described by the local strain rate and dynamics exhibits remarkable scaling properties when time is normalized by strain rate. The role of the solid friction at the cell walls has been investigated by polarimetry experie nces and solving numerically a poroelastic model of gel sedimentation
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Nascimento, Eduardo Souza do. "Lisina para frangos de corte de crescimento lento criados em sistema de semiconfinamento." Universidade Federal Rural do Rio de Janeiro, 2008. https://tede.ufrrj.br/jspui/handle/jspui/1733.
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The experiment aimed to analyse the effects of the level of lysine in the ration on performance, carcass characteristics and economic indicators of broilers raised in a free-range system in the periods ranging 35 to 70 and from 35 to 84 days age. The experimental design was the completely randomised with five tretments and four repetitions of 15 broilers each. The treatments were constituted of the values of 0.680; 0.840; 1.000; 1.160 and 1.320% of total of lysine in the ration (0.586; 0.746; 0.906; 1.066 and 1.226% of digestible lysine). In the period form 35 to 70 days age the levels of lysine influenced the final live weight of the broilers and it was estimated the level in 1.130% which would afford the best final live weight (2630g). The level of 1.135% of lysine in the ration would result in a bigger gain of weight (1641g). The broilers presented a linear growth in the ration consumption and linear reduction in the efficiency of of lysine utilization with the increase of the lysine levels in the ration. It was estimated a value of 1.046% of total lysine (0,952% of diestible lysine) which would result in a best feed: gain ratio (2.98). In the period from 35 to 84 days age the following values were estimated: 1.189% of total lysine (1.095% of diestible lysine) to bigger live weight (3211g), 1.196% of total lysine (1.102% of diestible lysine) to bigger gain of weight (2220g) and 1.078% of total lysine (0.984% of diestible lysine) to best feed: gain ratio (3,28).The increasing levels of lysine in the ration resulted in a linear increase in the ingestion of lysine and linear reduction in the efficiency lysine utilization. In relation to the carcass characteristics of broilers slaughtered at 70 days age, quadractic effects on the live weight after fasting and on the absolute weight of the hot carcass, abdominal fat, breast, thigh+drumstick and wing were observed. The studied levels of lysine influenced quadracticly the yield of breast and back and the relative weight of abdominal fat and gizzard. The levels of lysine influenced quadracticly the breast and back yield and the relative weight of the abdominal fat and gizzard. Linear increases in the absolute weight of the back, heart, liver, cecos and feet and linear reduction in the absolute weight of the proventricle and in the relative weight of the small intestine were observed. In the period from 35 to 84 days age quadractic effects on the absolute weight of the hot carcass, carcass yield, breast thigh+drumstick and back, in the heart and in the small intestine were observed. Linear increases in the live weight after fasting, in the absolute weight of the wing and liver, in the breast and thigh+drumstick and a linear reduction in the relative weight of the proventricle were observed. The levels of lysine did not influenced the other studied parameters. It was estimated that the ration with the level of 1.160% of total lysine (1.066% of digestible lysine) determined the biggest rate of the gross margin average by liver weight and of the gross margin average by weight gain in both studied periods. After 35 days age it is recomended to the male broilers of slow growing raised in a free-range system ration with 1.135% of total lysine (1.041% of digestible lysine) and with 1.196% of total lysine (1.102% of digestible lysine) respectively, to the slaughter at 70 and at 84 days age.
O experimento teve como objetivos avaliar os efeitos do n?vel de lisina na ra??o sobre o desempenho, caracter?stica de carca?a e indicadores econ?micos de frangos de corte machos de crescimento lento, criados em semiconfinamento, nos per?odos de 35 a 70 e 35 a 84 dias de idade. Foi adotado o delineamento inteiramente casualizado com cinco tratamentos e quatro repeti??es de 15 aves cada. Os tratamentos foram constitu?dos pelos valores de 0,680; 0,840; 1,000; 1,160 e 1,320% de lisina total na ra??o (0,586; 0,746; 0,906; 1,066 e 1,226% de lisina digest?vel). No per?odo de 35 a 70 dias de idade, os n?veis de lisina influenciaram no peso vivo final dos frangos sendo estimado o n?vel de 1,130% de lisina total que proporcionaria o melhor peso vivo (2630g). Para o ganho de peso o n?vel de 1,135% de lisina total na ra??o resultaria no maior ganho de peso (1641g). Os frangos apresentaram aumento linear no consumo de ra??o e redu??o linear na efici?ncia de utiliza??o de lisina com o aumento dos n?veis de lisina na ra??o. Para convers?o alimentar foi estimado em 1,046% lisina total (0,952% de lisina digest?vel) o valor que proporcionaria a melhor convers?o alimentar (2,98). No per?odo de 35 a 84 dias de idade foram estimados os seguintes valores de: 1,189% de lisina total (1,095 de lisina digest?vel) para maior peso vivo (3211g), 1,196% de lisina total (1,102% de lisina digest?vel) para maior ganho de peso (2220g) e 1,078% de lisina total (0,984 de lisina digest?vel) para melhor convers?o alimentar (3,28). Os n?veis crescentes de lisina nas ra??es resultaram em aumento linear na ingest?o de lisina e em redu??o linear na efici?ncia de utiliza??o de lisina. Quanto ?s caracter?sticas de carca?a de frangos abatidos aos 70 dias de idade, foram observados efeitos quadr?ticos sobre o peso vivo p?s o jejum e nos pesos absolutos da carca?a quente, da gordura abdominal, do peito, coxa+sobrecoxa e asa. Os n?veis de lisina pesquisados influenciaram de forma quadr?tica no rendimento do peito e dorso e nos pesos relativos da gordura abdominal e da moela. Foram observados aumentos lineares nos pesos absolutos do dorso, cora??o, f?gado, cecos e p?s e redu??es lineares nos pesos absolutos do proventr?culo e nos pesos relativos do proventr?culo e intestino delgado. No per?odo de 35 a 84 dias de idade, foram observados efeitos quadr?ticos sobre o peso absoluto da carca?a quente, rendimento de carca?a, no peito, coxa+sobrecoxa e dorso, no cora??o e no intestino delgado. Foram observados aumentos lineares no peso vivo p?s-jejum, nos pesos absolutos da asa e f?gado, nos rendimentos de peito e coxa+sobrecoxa e uma redu??o linear no peso relativo do proventr?culo. Os n?veis de lisina n?o influenciaram os demais par?metros estudados. Foi estimado que a ra??o com o n?vel de 1,160% de lisina total (1,066% de lisina digest?vel) determinou os maiores ?ndices de margem bruta m?dia por vivo e de margem bruta m?dia por ganho de peso, nos dois per?odos estudados. Para frangos de corte machos de crescimento lento e criados em semiconfinamento, recomenda-se ? partir dos 35 dias de idade, ra??o com 1,135% de lisina total (1,041% de lisina digest?vel) e com 1,196% de lisina total (1,102% de lisina digest?vel), respectivamente, para o abate aos 70 e aos 84 dias de idade.
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Charpak, Serge. "La transmission glutamatergique lente dans le systeme nerveux central de rat : role des recepteurs metabotropiques." Paris 6, 1991. http://www.theses.fr/1991PA066063.
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Nous avons effectue des enregistrements intracellulaires, dans des cultures organotypiques d'hippocampe de rat, afin de caracteriser les repercussions electriques membranaires provenant de l'activation des recepteurs glutamatergiques metabotropiques. Nous rapportons que l'application exogene d'agonistes metabotropiques le glutamate, le quisqualate et l'acide 1-aminocyclopentyl-trans-1,3-dicarboxylique (acpd) entraine une excitation lente resultant du blocage de deux courants potassiques, i#m et i#a#h#p. Couplant nos mesures electriques a la mesure de la concentration cytoplasmique du calcium libre (fura-2), nous montrons que la reponse metabotropique n'est pas correlee aux variations eventuelles de la concentration du calcium. L'etude de la transmission synaptique au niveau d'une synapse glutamatergique (fibres moussues-cellules pyramidales (ca3)) nous a permis d'etablir que la liberation de glutamate endogene produit, en sus d'une reponse ionotropique, une excitation lente caracteristique d'une reponse metabotropique. Notre travail suggere donc que le glutamate, dans des conditions physiologiques, agit comme un neurotransmetteur rapide lorsqu'il active les recepteurs ionotropiques, et comme un neurotransmetteur lent lorsqu'il active les recepteurs metabotropiques. L'acide l-1-amino-4-phosphonobutyrique (l-ap4), analogue glutamatergique normalement denue d'effet postsynaptique, se comporte comme un agoniste ionotropique et metabotropique lorsqu'il est applique apres le quisqualate. Notre travail analyse les mecanismes rendant compte de cette sensibilisation
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Barros, Silvana de. "Efeito da respiração lenta na pressão arterial e na função autonômica em hipertensos." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/5/5148/tde-22092017-134829/.
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INTRODUÇÃO: A respiração lenta é indicada como tratamento não medicamentoso da hipertensão arterial. Porém, os mecanismos fisiológicos envolvidos na redução da pressão arterial (PA) ainda são desconhecidos. A redução na atividade nervosa simpática (ANS) pode ser um dos mecanismos envolvidos na redução da PA. OBJETIVOS: Avaliar o efeito crônico da respiração lenta na PA e na ANS em hipertensos. MÉTODOS: Foram randomizados hipertensos, com e sem uso de anti-hipertensivos, em grupo controle (GC), orientados a ouvir músicas serenas com uso de aparelho de MP3, ou grupo respiração lenta (GRL), treinados a reduzir a frequência respiratória com auxílio de um dispositivo eletrônico, tendo como alvo terapêutico uma frequência respiratória menor que 10 respirações por minuto, por um período de 15 minutos diários, durante 8 semanas. Antes e após o período de intervenção, foi realizada monitorização ambulatorial da pressão arterial (MAPA), dosagem de catecolaminas plasmáticas e medida da atividade nervosa simpática periférica (ANSP) pela técnica da microneurografia. RESULTADOS: Completaram o estudo 17 voluntários no GRL e 15 no GC. Não houve mudança na PA de consultório antes e após a intervenção nos dois grupos. Observou-se redução na pressão arterial sistólica (PAS) e diastólica (PAD) na vigília entre os períodos pré e pós-intervenção apenas no GC (131±10 / 92±9 vs 128±10 / 88±8 mmHg, p < 0,05). Não foi observada diferença na concentração de catecolaminas plasmáticas (pg/ml) em ambos os grupos entre os períodos pré e pós-intervenção: GRL 302 (220-256) vs 234 (156-318), p=0,35; e GC 201 (144-230) vs 221 (179-274), p=0,97. Nos voluntários que realizaram microneurografia, GRL (n=10) e GC (n=10), observou-se redução significativa da PAD de sono entre os períodos pré e pós- intervenção apenas no GC (83±6 vs 79±4 mmHg, p < 0,05) A ANSP (impulsos/minuto) medida pela microneurografia apresentou elevação no período pós-intervenção em comparação ao período pré-intervenção nos dois grupos: GRL (16±6 vs 22±8, p < 0,05) e GC (20±5 vs 23±5, p < 0,05). CONCLUSÕES: A respiração lenta, realizada por 15 minutos diários durante 8 semanas, não reduziu a pressão arterial, os níveis de catecolaminas plasmáticas e a atividade nervosa simpática periférica de hipertensosINTRODUCTION: Slow breathing is indicated as nonpharmacological treatment of hypertension. However, the physiological mechanisms involved in blood pressure (BP) reduction are still unknown. The decrease in sympathetic nerve activity (SNA) may be one of the mechanisms involved in BP reduction. OBJECTIVES: To evaluate the chronic effect of slow breathing on BP and SNS in hypertensive patients. METHODS: Hypertensive patients, with or without use of antihypertensive drugs, were randomized to listen serene songs using an MP3 player (Control Group - CG) or device-guided slow breathing group (DGB), who were trained to reduce respiratory rate with assistance of an electronic device, targeting a respiratory rate of less than 10 breaths per minute, for a period of 15 minutes per day for 8 weeks. Before and after the intervention period, ambulatory blood pressure monitoring (ABPM), plasma catecholamines concentration and muscle sympathetic nerve activity (MSNA) using the microneurography technique were performed. RESULTS: 17 volunteers in the DGB and 15 in the CG completed the study. There was no change in office BP before and after intervention in both groups. There was a reduction in daytime systolic (SBP) and diastolic (DBP) before and after intervention only in the CG (131±10 / 92±9 vs 128±10 / 88±8 mmHg, p < 0,05). No difference in plasma catecholamines concentration (pg/ml) was observed in both groups before and after intervention: DGB 302 (220-256) vs 234 (156-318), p = 0.35; CG 201 (144-230) vs 221 (179-274), p=0.97. In the volunteers who underwent microneurography, DGB (n=10) and CG (n=10), there was a significant reduction in sleep DBP only in the CG: 83±6 vs 79±4 mmHg, p < 0,05. The MSNA (bursts/minute) measured by the microneurography showed a rise after the intervention in both groups: DGB (16±6 vs 22±8, p < 0.05) and CG (20±5 vs 23±5, p < 0.05). CONCLUSIONS: Slow breathing, performed for 15 minutes daily for 8 weeks, did not reduce blood pressure, plasma catecholamine concentration and muscle sympathetic nerve activity in hypertensive patients
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Coppa, Isabel Patricia Maria, and Isabel coppa@csw com au. "The use of remote sensing data for broad acre grain crop monitoring in Southeast Australia." RMIT University. Mathematical and Geospatial Sciences, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20070201.095831.
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In 2025, there will be almost 8 billion people to feed as the worlds population rapidly increases. To meet domestic and export demands, Australian grain productivity needs to approximately triple in the next 20 years, and this production needs to occur in an environmentally sustainable manner. The advent of Hi-tech Precision Farming in Australia has shown promise in recent time to optimize the use of resources. Most
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Schuartz, Fábio César. "Múltiplas antenas como alternativa para aumentar a taxa de extração de chaves secretas em redes veiculares com desvanecimento lento." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1797.
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A comunicação em redes veiculares ad hoc (VANETs) é comumente dividida em dois cenários, chamados veículo-a-veículo (V2V) e veículo-a-infraestrutura (V2I). Objetivando estabelecer uma comunicação segura contra espiões, trabalhos recentes tem proposto a troca de chaves secretas baseado na variação da força do sinal recebido (RSS). Entretanto, o bom desempenho de tal método depende da taxa de variação do canal, sendo mais apropriado a cenários em que o canal varia rapidamente, como geralmente é o caso da comunicação V2V. Já na comunicação V2I, o canal normalmente possui desvanecimento lento. Neste trabalho, é proposta a utilização de múltiplas antenas com o intuito de gerar artificialmente um canal de desvanecimento rápido, permitindo assim a extração de chaves secretas através da RSS em um cenário V2I. Análises numéricas mostram que o modelo proposto pode obter desempenho superior, em termos de taxa de extração de bits secretos, do que o modelo de salto em frequência proposto na literatura.The communication in vehicular ad hoc networks (VANETs) is commonly divided in two scenarios, namely vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I). Aiming at establishing secure communication against eavesdroppers, recent works have proposed the exchange of secret keys based on the variation in received signal strength (RSS). However, the performance of such scheme depends on the channel variation rate, being more appropriate for scenarios where the channel varies rapidly, as is usually the case with V2V communication. In the communication V2I, the channel commonly undergoes slow fading. In this work we propose the use of multiple antennas in order to artificially generate a fast fading channel so that the extraction of secret keys out of the RSS becomes feasible in a V2I scenario. Numerical analysis shows that the proposed model can outperform, in terms of secret bit extraction rate, a frequency hopping-based method proposed in the literature.
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Araujo, Tatiana Goveia de. "Efeito agudo da respiração lenta guiada após exercício físico aeróbio na atividade nervosa simpática periférica e pressão arterial em indivíduos hipertensos." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/5/5148/tde-25102017-113241/.
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INTRODUÇÃO: Terapias não medicamentosas têm sido amplamente recomendadas para o controle da hipertensão. Dentre elas, destacam-se os exercícios aeróbios (EXE) e o equipamento de respiração guiada (Resperate®). Este dispositivo tem demonstrado importante efeito hipotensor através da redução da frequência respiratória (FR). Não se sabe, porém, a resposta deste equipamento após outra forma de intervenção. Investigamos, portanto, o efeito agudo do Resperate®, após EXE, na atividade nervosa simpática periférica (ANSP) e PA pela MAPA, versus controle. MÉTODOS: Foram avaliados 29 hipertensos estágios I e II entre 32 e 60 anos, de ambos os sexos, sedentários, não obesos, sem lesão de órgãos-alvo, sem comorbidades associadas e após quatro semanas de uso de placebo, divididos em grupo de respiração lenta (GRL) e controle (GC). Os participantes realizavam MAPA inicial 24h antes da sessão experimental. No dia da sessão, foram registrados inicialmente (basal), a pressão arterial sistólica (PAS), pressão arterial diastólica (PAD), FR e frequência cardíaca (FC). Ao término deste registro dava-se início ao exercício na bicicleta (EXE). Em seguida, foi realizado também o registro da microneurografia e, após a localização do nervo fibular, os registros foram divididos em três períodos: pré-respiratório (10min), respiratório (15min) e recuperação (10min). No período respiratório, o GRL, iniciava a respiração lenta e, após a FR atingir 10 ou menos respirações por minuto os dados eram registrados. Já o GC, ouvia música calma com FR livre. Finalizado a recuperação, a MAPA final era instalada, e o voluntário era dispensado. RESULTADOS: Completaram o estudo 14 homens e 15 mulheres, com média de idade de 49±8 anos no GRL e 51±5 anos no GC (P= 0,345) e índice de massa corpórea (IMC) de 26,3±2,8kg/m2 no GRL e 27,4±2,0 kg/m2, no GC, P=0,272. Os grupos eram semelhantes, com VO2pico de 21,5±3 ml.kg-1.min-1 para o GC e de 24,4±5,3 ml.kg-1.min-1 para o GRL (P=0,083); PA de consultório (após o período placebo) com média de 145±1/93±4 mmHg, no GRL e 143±7/ 95±7 mmHg no GC (P=0,456/0,201, respectivamente para PAS e PAD). No GRL, houve redução significativa da FR de 17±7 para 7±1 rpm (P=0,000) durante o período respiratório. A PAS 24h reduziu nos dois grupos de 141±10 para 138±1 (P= 0,034) no GRL e de 137±10 para 131±9 (P=0,024) no GC, assim como na PAS durante a vigília de 146±11 para 143±11 mmHg (p=0,021) no GRL e de 139±8 para 135 ±10 mmHg (P=0,023) no GC, sem diferença entre os grupos, P=0,978. No sono, apenas no GC, de 131±12 para 123±9,84 (P=0,009). Não houve diferença no comportamento da ANSP que variou no GRL de 24±8 para 24±9, P=1,000) e no GC de 23±11 para 24±10 (P=1,000) impulsos/min. CONCLUSÕES: O exercício de respiração lenta não foi capaz de oferecer benefícios adicionais ao EXE, em comparação ao GC, nos indivíduos avaliadosNon-drug therapies have been widely recommended for the control of hypertension. Among them, aerobic exercises (EXE) and device guided breathing (Resperate®) are highlight. This device has demonstrated a hypotensive effect by reducing respiratory rate (RR). However, it is not known the response of this device after another form of intervention. This study investigated the acute effect of Resperate®, after EXE, on the peripheral sympathetic nervous activity (MSNA) and blood pressure (BP) by 24-hour ambulatory BP (ABPM), versus control. METHODS: Twenty-nine hypertensive I and II stages were studied. They ranged from 32 to 60 years of age, both sexes, sedentary, non-obese, without target organ damage and associated comorbidities, with a placebo washout of 4 weeks. They were divided into breathing (GRL) and control groups (GC). They performed an initial ABMP prior to the experimental session. At the experimental session, systolic blood pressure (SBP), diastolic blood pressure (DBP), RR and heart rate (HR) were initially recorded (baseline). After that, cycling (EXE) was performed and then the fibular nerve was located. The microneurography records were divided into three periods: pre-respiratory (10min), respiratory (15min) and recovery (10min). In the respiratory period, GRL started the guided breathing and after RR reached 10 or less breaths/ minute, data were recorded. The GC listened to calm music with free RR. After the recovery, the ABPM was placed, and the subjects went home. RESULTS: 14 men and 15 women completed the study. Mean age was 49 ± 8 years in GRL and 51 ± 5 years in CG (P= 0.345). The body mass index was 26.3 ± 2.8 kg / m2 in GRL and 27.4 ± 2.0 kg / m2 in GC, (P = 0.272). The VO2 peak were: 21.5 ± 3 ml.kg-1.min-1 in GC and 24.4 ± 5.3 ml.kg-1.min-1 in GRL (P=0,083); After the placebo period SBP / DBP were similar between groups: 145 ± 1/93 ± 4 mmHg in GRL and 143 ± 7/95 ± 7 mmHg in CG (P = 0.456 / 0.201). There was a significant reduction in RR in GRL from 17 ± 7 to 7 ± 1 breaths/min (P=0.000) during the respiratory period. The SBP 24h reduced in both groups from 141 ± 10 for 138 ± 1 (P = 0.034) in the GRL and 137 ± 10 for 131 ± 9 (P = 0.024), as well as SBP (awake): from 146 ± 11 to 143 ± 11 mmHg in GRL (P=0,021) and from 139 ± 8 to 135 ± 10 mmHg in GC (P=0,023), with no difference between groups (P = 0.978). At sleep, only the CG had SBP reduction from 131 ± 12 to 123 ± 9.84 (P=0.009). The MSNA was unchanged ranging from 24 ± 8 to 24 ± 9 in GRL, (P=1.000) and from 23 ± 11 to 24 ± 10 (P= 1.000) in CG burst/min. CONCLUSIONS: Slow-breathing exercise was not able to offer additional sympathetic nerve activity or blood pressure reduction after EXE, in this sample
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Castanheiro, Letícia Ferrari. "Geometric model of a dual-fisheye system composed of hyper-hemispherical lenses /." Presidente Prudente, 2020. http://hdl.handle.net/11449/192117.
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Orientador: Antonio Maria Garcia TommaselliResumo: A combinação de duas lentes com FOV hiper-hemisférico em posição opostas pode gerar um sistema omnidirecional (FOV 360°) leve, compacto e de baixo custo, como Ricoh Theta S e GoPro Fusion. Entretanto, apenas algumas técnicas e modelos matemáticos para a calibração um sistema com duas lentes hiper-hemisféricas são apresentadas na literatura. Nesta pesquisa, é avaliado e definido um modelo geométrico para calibração de sistemas omnidirecionais compostos por duas lentes hiper-hemisféricas e apresenta-se algumas aplicações com esse tipo de sistema. A calibração das câmaras foi realizada no programa CMC (calibração de múltiplas câmeras) utilizando imagens obtidas a partir de vídeos feitos com a câmara Ricoh Theta S no campo de calibração 360°. A câmara Ricoh Theta S é composto por duas lentes hiper-hemisféricas fisheye que cobrem 190° cada uma. Com o objetivo de avaliar as melhorias na utilização de pontos em comum entre as imagens, dois conjuntos de dados de pontos foram considerados: (1) apenas pontos no campo hemisférico, e (2) pontos em todo o campo de imagem (isto é, adicionar pontos no campo de imagem hiper-hemisférica). Primeiramente, os modelos ângulo equisólido, equidistante, estereográfico e ortogonal combinados com o modelo de distorção Conrady-Brown foram testados para a calibração de um sensor da câmara Ricoh Theta S. Os modelos de ângulo-equisólido e estereográfico apresentaram resultados melhores do que os outros modelos. Portanto, esses dois modelos de projeção for... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The arrangement of two hyper-hemispherical fisheye lenses in opposite position can design a light weight, small and low-cost omnidirectional system (360° FOV), e.g. Ricoh Theta S and GoPro Fusion. However, only a few techniques are presented in the literature to calibrate a dual-fisheye system. In this research, a geometric model for dual-fisheye system calibration was evaluated, and some applications with this type of system are presented. The calibrating bundle adjustment was performed in CMC (calibration of multiple cameras) software by using the Ricoh Theta video frames of the 360° calibration field. The Ricoh Theta S system is composed of two hyper-hemispherical fisheye lenses with 190° FOV each one. In order to evaluate the improvement in applying points in the hyper-hemispherical image field, two data set of points were considered: (1) observations that are only in the hemispherical field, and (2) points in all image field, i.e. adding points in the hyper-hemispherical image field. First, one sensor of the Ricoh Theta S system was calibrated in a bundle adjustment based on the equidistant, equisolid-angle, stereographic and orthogonal models combined with Conrady-Brown distortion model. Results showed that the equisolid-angle and stereographic models can provide better solutions than those of the others projection models. Therefore, these two projection models were implemented in a simultaneous camera calibration, in which the both Ricoh Theta sensors were considered i... (Complete abstract click electronic access below)
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Traoré, Flavien. "La composante lente du courant potassique sortant du muscle squelettique de grenouille : sa dependance vis-a-vis du calcium intracellulaire." Poitiers, 1987. http://www.theses.fr/1987POIT2255.
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Silva, Yuri C?sar de Lima e. "Pol?ticas recentes para arranjos produtivos locais: um olhar sob a lente dos organismos respons?veis pelo apoio no estado do Rio Grande do Norte." Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/18307.
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Previous issue date: 2011-07-11This paper aims to analyze the current support structure ready to Local Productive Arrangements (APLs) in the state of Rio Grande do Norte. To this end, it was done a study of major theories dealing with territorial agglomerations: moving from the pioneering concept of Marshallian industrial district to neo-Schumpeterian concepts coming from the latest innovation systems. In a complementary way, there will be a study of the major reasons that brought the crowded productive activities to a central position in the economic debate and the formation of public policy, seeking to understand what the relationship of this phenomenon with the different approaches of regional development policies which are included in recent years. Finally, it sought to understand how the bodies responsible for supporting clusters in the state of Rio Grande do Norte act in the selection and support of these arrangements, analyzing what the main policies implemented and trying to understand what are the main instruments used to support these clusters in the state
Este trabalho pretende analisar a atual estrutura de apoio disposta aos Arranjos Produtivos Locais (APLs) no estado do Rio Grande do Norte. Com este intuito, realiza-se um estudo das principais teorias que tratam das aglomera??es territoriais: passando desde o conceito pioneiro de distrito industrial marshalliano at? conceitos neo-schumpeterianos mais recentes provindo dos sistemas de inova??o. De maneira complementar, realiza-se um estudo dos principais motivos que trouxeram as atividades produtivas aglomeradas a uma posi??o central no debate econ?mico e na forma??o de pol?ticas p?blicas, procurando compreender qual a rela??o deste fen?meno com as diferentes abordagens das pol?ticas de desenvolvimento regional compreendidas nos ?ltimos anos. Por fim, pretendeu-se compreender de que forma os ?rg?os respons?veis pelo apoio aos APLs no estado do Rio Grande do Norte atuam na sele??o e apoio a estes arranjos, analisando quais as principais pol?ticas implementadas e procurando compreender quais s?o os principais instrumentos utilizados no apoio a estes APLs no estado
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Fontanari, Daniele. "Quantum manifestations of the adiabatic chaos of perturbed susperintegrable Hamiltonian systems." Thesis, Littoral, 2013. http://www.theses.fr/2013DUNK0356/document.
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Dans cette thèse nous étudions un système quantique, obtenu comme un analogue d'un système classique superintégrable perturbé au moyen de la quantification géométrique. Notre objectif est de mettre en évidence la présence des phénomènes analogues à ceux qui caractérisent la superintégrabilité classique, notamment la coexistence des mouvements réguliers et chaotiques liés aux effets des résonances ainsi que la régularité du régime non-résonant. L'analyse est effectuée par l'étude des distributions du Husimi des états quantiques sélectionnés, avec une attention particulière aux états stationnaires et à l'évolution des états cohérents. Les calculs sont effectués en utilisant les méthodes numériques et les méthodes perturbatives. Les calculs sont effectués en utilisant les méthodes numériques et les méthodes perturbatives. Bien que cette thèse devrait être considérée comme une étude préliminaire, dont l'objectif est de créer le socle des études futures, nos résultats donnent des indications intéressantes sur la dynamique quantique. Par exemple, il est démontré comment les résonancees classiques exercent une influence considérable sur le spectre du système quantique et comment il est possible, dans le comportement quantique, de trouver une trace de l'invariant adiabatique dans le régime de résonanceThe abundance, among physical models, of perturbations of superintegrable Hamiltonian systems makes the understanding of their long-term dynamics an important research topic. While from the classical standpoint the situation, at least in many important cases, is well understood through the use of Nekhoroshev stability theorem and of the adiabatic invariants theory, in the quantum framework there is, on the contrary, a lack of precise results. The purpose of this thesis is to study a perturbed superintegrable quantum system, obtained from a classical counterpart by means of geometric quantization, in order to highlight the presence of indicators of superintegrability analogues to the ones that characterize the classical system, such as the coexistence of regular motions with chaotic one, due to the effects of resonances, opposed to the regularity in the non resonant regime. The analysis is carried out by studying the Husimi distributions of chosen quantum states, with particular emphasis on stationary states and evolved coherent states. The computation are performed using both numerical methods and perturbative schemes. Although this should be considered a preliminary work, the purpose of which is to lay the fundations for future investigations, the results obtained here give interesting insights into quantum dynamics. For instance, it is shown how classical resonances exert a considerable influence on the spectrum of the quantum system and how it is possible, in the quantum behaviour, to find a trace of the classical adiabatic invariance in the resonance regime
L'abbondanza, fra i modelli fisici, di perturbazioni di sistemi Hamiltoniani superintegrabili rende la comprensione della loro dinamica per tempi lunghi un importante argomento diricerca. Mentre dal punto di vista classico la situazione, perlomeno in molti case importanti, è ben compresa grazie all'uso del teorema di stabilità di Nekhoroshev e della teoria degli invariantiadiabatici, nel caso quantistico vi è, al contrario, una mancanza di risultati precisi. L'obiettivo di questa tesi è di studiare un sistema superintegrabile quantistico, ottenuto partendo da un corrispettivo classico tramite quantizzazione geometrica, al fine di evidenziare la presenza di indicatori di supertintegrabilità analoghi a quelliche caratterizzano il sistema classico, come la coesistenza di moti regolari e caotici, dovuta all'effetto delle risonanze, in contrapposizione con la regolarità nel regime non risonante. L'analisi è condotta studiando le distribuzioni di Husimi di stati quantistici scelti, con particolare enfasi posta sugli stati stazionari e sugli stati coerenti evoluti. I calcoli sono effettuati sia utilizzando tecniche numeriche che schemi perturbativi. Pur essendo da considerardi questo un lavoro preliminare, il cui compito è di porre le fondamenta per analisi future, i risultati qui ottenuti offrono interessanti spunti sulla dinamica quantistica. Per esempio è mostrato come le risonanze classiche abbiano un chiaro effeto sullo spettro del sistema quantistico, ed inoltre comesia possibile trovare una traccia, nel comportamento quantistico, dell'invarianza adiabatica classica nel regime risonante
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Silva, Leandro José Beraldo e. "Propriedades dinâmicas da matéria escura." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-06072015-114443/.
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Esta tese tem como objetivo o estudo de aspectos dinâmicos e estatísticos da matéria escura em distribuições esféricas de massa. O fato de suas partículas constituintes interagirem gravitacionalmente mas não eletromagneticamente, e portanto sua evolução ser regida por interações de longo alcance, traz algumas complicações teóricas na descrição de suas propriedades nos termos da mecânica estatística, dificuldades compartilhadas com sistemas auto-gravitantes em geral. Para melhor compreender essas propriedades, estudamos as distribuições de matéria escura em três abordagens diferentes. Na primeira, utilizamos dados observacionais, utilizando lentes gravitacionais, em aglomerados de galáxias para comparar a performance de alguns modelos propostos para o perfil de densidade da matéria escura. Dividimos estes modelos em fenomenológicos ou teóricos. Dos primeiros, todos são capazes de descrever os dados observacionais com performance comparável. Entre os modelos teóricos estudados, o modelo chamado DARKexp descreve os dados tão bem quanto os primeiros. Numa segunda abordagem, utilizamos dados de simulações numéricas para testar uma função proposta para a distribuição de velocidades das partículas. Esta função inclui a anisotropia no campo de velocidades na chamada distribuição q-gaussiana. Comparamos a performance desta função com a da função gaussiana e concluímos que a primeira representa uma melhor descrição dos dados, mesmo levando em conta a introdução de um parâmetro extra, apesar de ainda apresentar algumas discrepâncias, especialmente nas regiões internas dos halos. Por fim, discutimos a possível relevância do conceito de indistinguibilidade na determinação dos estados de equilíbrio de sistemas auto-gravitantes em geral, propondo uma associação deste conceito com o nível de mistura do sistema. Implementamos esta associação numa análise combinatória e estudamos as conseqüências para a determinação da função distribuição e do perfil de densidades. Esta associação também levanta algumas dúvidas sobre a validade da equação de Vlasov durante o processo de relaxação violenta.This thesis aims to study the dynamic and statistical aspects of dark matter in spherical distributions. The fact that their constituent particles interact gravitationally but not electromagnetically, and therefore its evolution is governed by long-range interactions, brings some theoretical complications in their description in terms of the statistical mechanics, difficulties shared with self-gravitating systems in general. To better understand these properties, we studied the distributions of dark matter in three different approaches. First, we used observational data, using gravitational lensing in galaxy clusters to compare the performance of some proposed models for the dark matter density profile. We divide these models in phenomenological or theoretical. All of the formers are able to describe the observational data with comparable performance. Among the theoretical models studied, the model called DARKexp describes the data as well as the formers. In a second approach, we use numerical simulation data to test a proposed function for the velocity distribution. This function includes the velocity anisotropy into the so called q-Gaussian distribution. We compared the performance of this function with the Gaussian function and concluded that the first is a better description of the data, even taking into account the introduction of an extra parameter, although still presenting some discrepancies, especially in the inner regions of the halo. Finally, we discuss the relevance of the concept of indistinguishability in determining the states of equilibrium of self-gravitating systems in general, suggesting an association of this concept with the mixing level of the system. We implement this association in a combinatorial analysis and study the consequences for the determination of the distribution function and the density profile. This association also raises some questions about the validity of the Vlasov equation during the process of violent relaxation.
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Hajji, Miled El. "Modélisation et analyse mathématiques pour les écosystèmes microbiens : approche par les systèmes dynamiques." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20117/document.
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Cette thèse s'adresse au problèmes relié au modélisation mathématique en culture continue et culture batch. Nous proposons et étudions, dans une première étape, des modèles mathématiques de quelques processus biologique en culture continue (Chemostat) permettant d'expliquer et de prévoir la coexistence et la coexistence pratique. Dans une deuxième étape, une série d'expériences de laboratoire sont munies en culture batch, et un modèle mathématique tenant compte du recyclage de substrat est proposé, analysé et validé sur des donnés expérimentales en culture pure et mixte prouvant la validité de la principe d'exclusion compétitive en culture batchCette thèse s'adresse au problèmes relié au modélisation mathématique en culture continue et culture batch. Nous proposons et étudions, dans une première étape, des modèles mathématiques de quelques processus biologique en culture continue (Chemostat) permettant d'expliquer et de prévoir la coexistence et la coexistence pratique. Dans une deuxième étape, une série d'expériences de laboratoire sont munies en culture batch, et un modèle mathématique tenant compte du recyclage de substrat est proposé, analysé et validé sur des donnés expérimentales en culture pure et mixte prouvant la validité de la principe d'exclusion compétitive en culture batch
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Junier, Ivan. "Etude de systemes hors equilibre." Phd thesis, Université Paris-Diderot - Paris VII, 2004. http://tel.archives-ouvertes.fr/tel-00007153.
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Cette thèse concerne deux classes de systèmes hors équilibre. Premièrement, nous étudions des systèmes présentant des modes de Goldstone soumis à des champs oscillants: à l'aide de plusieurs champs orthogonaux, il est possible de réduire successivement la symétrie des modèles initiaux: un modèle Heisenberg peut devenir un modèle ayant une symétrie Ising. Deuxièmement, nous proposons des réalisations microscopiques des modèles de pièges introduits pour comprendre les phénomènes de vieillissement dans les verres. Seuls les modèles entropiques, par opposition à ceux dits activés, présentent des températures effectives différentes de celle du bain thermique. Enfin, nous généralisons les modèles d'espace de phases en considérant des évolutions locales en énergie.
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Mégret, Lucile. "Explosions de cycles : analyses qualitatives, simulations numériques et modèles." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066359/document.
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Ce travail porte sur de nouvelles explosions de cycles (orbites périodiques), l'étude de leur structure par l'analyse qualitative, leur mise en évidence par simulation numérique (Auto, Xpp) et la discussion de leur pertinence dans des modèles mathématiques dans les neurosciences. De telles explosions se produisent dans les systèmes dynamiques lents-rapides. La plupart des neurones sont excitables, dès 1940, Hodgkin identifia trois classes fondamentales d'axones excitables distinguées par leurs réponses à un courant injecté d'amplitude variable. A l'aide de la fonction de Lambert, nous étudions la transition entre les types I et II par des explosions de cycle incomplètes, initiées par une bifurcation de Hopf singulière et qui se terminent dans une bifurcation homocline dans des systèmes une variable rapide/une variable lente. Vient ensuite une étude poussée du système de Hindmarsh-Rose. Il s'agit d'un système deux variables rapides/une variable lente qui produit des oscillations en salves (ou bursting). Nous généralisons la notion d'ensembles candidats-limites-périodiques (clp) aux systèmes tridimensionnels, il s'agit des ensembles invariants du système à la limite singulière. A l'aide de ces derniers, nous obtenons une description très fine de la déformation du cycle limite jusqu'à l'addition d'un nouveau spike au burst. Nous finissons par une étude de la minimalité du modèle de F. Clément et J.-P. Françoise. Ce dernier est un système 4D qui modélise l¿activité des neurones à GnRH. Nous étudions un système une variable rapide/deux variables lentes qui reproduit certaines des caractéristiques du modèle 4D, notamment des Mixed-Modes oscillationsThis thesis is focussed on the analysis of novel explosions of limit cycles (periodic orbits). We provide a study of their structure by qualitative analysis, exhibit evidences of their existence by numerical simulations (Auto, Xpp) and propose a discussion of their relevance in mathematical modeling for neurosciences. Such explosions occur in the slow-fast dynamical systems. Most of neurons are excitable, Hodgkin (1940) identified three fundamental classes of excitable axon distinguished by their responses to a current of variable amplitude injected. Using the Lambert function, we study the transition between types I and II by incomplete explosion of cycle. This explosion, produced by a planar vector field with one fast/one slow variable, is initiated by a singular Hopf bifurcation and ends via a homoclinic bifurcation. The next chapter proposed a study of the Hindmarsh-Rose system. This system, composed of one fast/ two slow variables, is well known to produce square wave bursting oscillation. We generalize the notion of candidate-limit-perodic sets (CLP-sets) to three-dimensional systems. A CLP-set is an invariant set of the system in the singular limit. Using these, we get a very acurate description of the limit cycle deformation under the variation of a parameter until the addition of a new spike to burst. Finally, we propose a study fot the minimality of the model introduced by F. Clement and J.-P. Françoise. The latter is a 4D system that models the activity of GnRH neurons. We study a system composed by one fast /two slow variables that reproduces some of the features of the 4D model, including Mixed-Modes oscillations
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Bertholdi, Angelo Albano da Silva. "Aquisição do carbono e atividade fotoquímica em sistemas de restauração ecológica com estrutura e diversidade de espécies contrastantes." Botucatu, 2019. http://hdl.handle.net/11449/181325.
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Orientador: Luiz Fernando Rolim de AlmeidaResumo: A implantação de sistemas de restauração possibilita o restabelecimento da estrutura e funcionamento de ecossistemas degradados. Além disso, alta diversidade taxonômica e funcional dos sistemas de restauração garante a performance e estabilidade de ecossistemas restaurados. A efetividade e monitoramento dos sistemas de restauração são quantificados por variáveis alométricas, porém, desconsideram-se variáveis relacionadas a aquisição de carbono e atividade fotoquímica. Dessa forma, o objetivo deste estudo foi o avaliar as respostas ecofisiológicas de plantas em diferentes sistemas de restauração florestal e avaliar se a capacidade de perda de água e reidratação de espécies de crescimento rápido e lento favorece o estabelecimento e desenvolvimento de sistemas de restauração com estrutura e diversidade de espécies contratantes. Portanto, avaliamos, durante um ano, variáveis relacionadas à disponibilidade de água no solo e ambiente, estrutura dos sistemas de plantio, relações hídricas, atividade fotoquímica e aquisição e acúmulo de carbono nas folhas, em 7 espécies (divididas em espécies de crescimento rápido e lento) pertencentes a três sistemas de restauração: plantio de alta diversidade, sistema agroflorestal e consórcio madeira e lenha, estes sistemas estão implantados em dois tipos de solo: Nitossolo Vermelho (Área 1 – solo argiloso) e Argissolo Vermelho Amarelo (Área 2 – solo arenoso). Os resultados indicaram que sistemas implantados na área 1 apresentaram maior eficiência ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The restoration systems implantation enables the restoration of degraded ecosystems structure and functioning. In addition, restoration systems high taxonomic and functional diversity guarantees restored ecosystems performance and stability. The restoration systems effective-ness and monitoring are quantified by allometric variables, however, variables related to carbon acquisition and photochemical activity are disregarded. Thus, the aim study was to evaluate the ecophysiological responses of plants in different forest restoration systems and to evaluate if the water loss and rehydration capacity of fast and slow growth species favors the establishment and development of systems with contracting structure and species diversity. Therefore, we evaluated, for one year, variables related to the soil and environment water availability, planting systems structure, water relations, photochemical activity and carbon acquisition in leaves, in 7 species (divided into fast and slow growth species). These systems are implanted in two soils types: fertile loamy Ultisol (Site 1) and sandy Alfisol soil (Site 2). The results indicated that systems implanted in site 1 showed higher photosynthetic efficiency and carbon accumulation during water deficiency periods. The wood and wood consortium presented lower complexity in the structure and higher photosynthetic efficiency in times with low water availability in the soil. The mixed plantation using commercial timber and firewood tree species o... (Complete abstract click electronic access below)
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Laborde, Sylvain. "Slow-paced breathing and cardiac vagal activity : influence on stress regulation, sleep, and cognitive executive performance The effect of slow-paced breathing on stress management in adolescents with intellectual disability Influence of a 30-day slow paced breathing intervention compared to social media use on subjective sleep quality and cardiac vagal activity The influence of slow-paced breathing on executive function Influence of slow-paced breathing on inhibition after physical exertion." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMC044.
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Cette thèse de doctorat a pour but d'étudier l’influence de la respiration lente contrôlée sans biofeedback sur l'activité vagale cardiaque ainsi que son action sur plusieurs processus d'autorégulation, en se basant sur le modèle d'intégration neuroviscérale (Smith et al., 2017 ; Thayer et al., 2009) et sur le modèle de résonance (Lehrer & Gevirtz, 2014). Quatre études ont été menées, auprès d'adolescents ayant un handicap mental (étude 1) et de jeunes adultes sains (études 2, 3 et 4). Les effets d’interventions courtes et longues basées sur la respiration lente contrôlée ont été étudiés, et des effets positifs ont été constatés sur la gestion du stress (intervention courte, étude 1), le sommeil (intervention longue, étude 2) et les fonctions exécutives (intervention courte, études 3 et 4), mais les effets sur les fonctions exécutives n'ont pas été médiés par l’activité vagale cardiaque. Ces résultats sont encourageants en ce qui concerne l'utilisation de la respiration lente contrôlée en tant qu’intervention à court et long terme, en tant que "solution rapide" ou routine quotidienne, mais les recherches futures doivent clarifier les mécanismes sous-jacents, en particulier en utilisant des méthodes d'imagerie cérébrale. En conclusion, la respiration lente contrôlée est une technique gratuite, non invasive, simple à mettre en œuvre, et avec peu d'effets secondaires, ce qui en fait une intervention appropriée pour traiter un éventail varié de phénomènes liés à l’autorégulationThis PhD thesis was aimed to investigate the influence of slow-paced breathing (SPB) without biofeedback on CVA, as well as its action on several self-regulation processes, based on the neurovisceral integration model (Smith et al., 2017; Thayer et al., 2009) and on the resonance model (Lehrer & Gevirtz, 2014). Four studies were conducted, adolescents with individual disabilities (Study 1) and healthy young adults (Study 2, 3, & 4). Both short-term and long-term SPB interventions have been investigated, and positive effects have been found on stress management (short-term, Study 1), sleep (long-term, Study 2), and executive functions (short-term, Studies 3 and 4), however results related to executive functions were not mediated by CVA. These results are encouraging regarding the use of SPB in acute and chronic interventions, as a “quick-fix” or daily routine, however future research has to clarify the underlying mechanisms, in particular with brain imaging methods. To conclude, SPB is a technique that is free, non-invasive, easy to implement, and with little side effects, which makes it an appropriate intervention to recommend to address a large range of self-regulation phenomena
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Perrillat-Mercerot, Angélique. "Modélisation et étude du métabolisme énergétique cérébral. Applications à l'imagerie des gliomes diffus de bas grade." Thesis, Poitiers, 2019. http://www.theses.fr/2019POIT2285/document.
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Tout ce qui vit, naît, se nourrit, se reproduit et meurt. Pour le cerveau, la question se complexifie car à la survie des neurones s'ajoute le coût de l'activité cérébrale. La question de la gestion énergétique pour les neurones est particulière car les cellules de notre cerveau évoluent de manière concertée et non par compétition. On sait avec l'imagerie médicale que l'usine neuronale ne fonctionne pas uniquement grâce au glucose ; elle utilise d'autres apports énergétiques tels que le lactate ou le glutamate pour soutenir sa production. Lorsqu'une tumeur apparaît, elle change le métabolisme énergétique pour survivre et soutenir sa propre croissance. En particulier, les cellules cancéreuses se fournissent en lactate et choisissent leur substrat préféré en fonction de l'oxygène disponible. La modélisation mathématique des substrats énergétiques est un outil de choix pour décrire et prédire de tels flux. Coupler ces modèles à des données issues de l'IRM et de la SRM permet d'améliorer la prise en charge du patient présentant un gliome.Cette thèse propose l'approche de plusieurs dynamiques en substrat dans le cerveau sain et gliomateux en se basant sur des systèmes d'équations : échanges locaux en lactate (EDO, système lent-rapide), échanges globaux en substrats (EDO), cycle glutamate/glutamine (EDR) et échanges en lactate en dimensions supérieures (EDP). Ces modèles sont expliqués, décrits grâce aux mathématiques et permettent l'élaboration de simulations ajustées selon des données patient ou issues de la littérature.L'énergie est nécessaire au maintien de la vie. Mais si votre voisin consomme une partie de vos ressources, pouvez-vous encore espérer survivre ?Everything that lives is born, eats, reproduces and dies. For the brain, the question is more complex because neurons have to survive and to support brain activity. Energy management is also particular because brain cells evolve together with no competition. Thanks to medical imaging, we know that neurons do not consume only glucose. They can use others energetic substrates such as lactate and glutamate as a power source.When a tumor appears, it changes the energetic metabolism to survive and support its own growth. In particular, cancer cells like to consume lactate. They also choose their favorite substrate based on the available oxygen. Modeling of energy substrates is useful to describe and predict energetic kinetics and changes. Mathematical models could get with clinical and medical results to describe, explain or predict low grade glioma dynamics. They can help to characterize and quantify a tumor evolution, then leading to improve their therapeutical management. Exchanges between mathematics and MRI (and MRS) enable to get accurate data and to build suitable mathematical models.This thesis deals with several approaches of substrates dynamics in healthy and gliomatous brains. These researches are based on systems of equations. We model local lactate exchanges (ODE, fast-slow systems), global substrates exchanges (ODE), glutamate/glutamine cycle (RDE) and local lactate exchanges in higher dimensions (PDE). We describe, analyze and give simulations of these models. Simulations are fitted on patient MRI data or literature data. Energy is necessary to live. But if your neighbor consumes a part of your resources, can you still survive ?
Tutto ciò che vive nasce, si nutre, si riproduce e muore. Per il cervello, la questione è più complessa perché i neuroni devono sopravvivere e sostenere l'attività cerebrale. La gestione energetica cerebrale è particolare anche perché le cellule cerebrali evolvono insieme, senza concorrenza. Inoltre, grazie alle immagini mediche, sappiamo che i neuroni non consumano solo del glucosio ma usano altri substrati energetici come il lattato o il glutammato.Quando un tumore si stabilisce, cambia il metabolismo energetico del cervello per sopravvivere e sostenere la propria crescita. In particolare, cellule tumorali consumano del lattato e scelgono il loro substrato preferito basandosi all'ossigeno disponibile.La matematica, e in particolare l'elaborazione di modelli matematici può aiutarci a ottimizzare i dati disponibili, che possono essere, di volta in volta, delle proprietà cellulare o delle lastre MRI o MRS. La modellizzazione dei substrati energetici potrebbe descrivere, spiegare o prevedere le dinamiche energetiche nel cervello.Questa tesi tratta di diversi approcci della dinamica dei substrati nei cervelli sani e gliomatosi. Queste ricerche si basano su sistemi di equazioni. Modellizziamo scambi locali di lattato (ODE, sistemi fast-slow), scambi globali di substrati (ODE), ciclo glutammato/glutammina (RDE) e scambi locali di lattato in dimensioni superiori (PDE). Descriviamo, analizziamo e diamo simulazioni di questi modelli. Le simulazioni sono adeguate su dati MRI paziente o dati di letteratura.Per vivere, l’energia è una necessità. Ma se i Suoi vicini consumassero le Sue risorse, riuscirebbe ancora a sopravvivere ?
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Bonnet, Celine. "Différentiation cellulaire, régulation des cellules souches et impact des mutations : une approche probabiliste." Thesis, Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAX016.
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Cette thèse porte sur la compréhension des mécanismes de différenciation cellulaire des cellules souches permettant la production des globules rouges (mécanisme appelé érythropoïèse). Nous avons élaboré différents modèles mathématiques permettant une compréhension à différents niveaux. Dans un premier temps, nous avons construit et calibré un modèle à 8 équations différentielles ordinaires pour décrire la dynamique de 6 populations de cellules en érythropoïèse de repos et de stress. L’étude de données expérimentales in vivo, recueillies par nos collaborateurs Stéphane Giraudier (hématologue) et Evelyne Lauret (INSERM), a montré la nécessité d’ajouter deux équations pour modéliser les régulations érythropoïètiques. La calibration du modèle a été effectuée à l’aide des données biologiques et d’un algorithme d’optimisation stochastique appelé CMA-ES. Ce modèle nous a permis de mettre en lumière l’importance de la capacité d’auto-renouvellement des cellules érythropoïètiques dans la production des globules rouges. L’élaboration d’un modèle probabiliste de dimension 3 nous a ensuite permis de comprendre les conséquences dynamiques de cette capacité sur la production des globules rouges. L’étude de ce modèle a nécessité des changements d’échelles en taille et en temps révélant un système dit lent/rapide. À l’aide de méthodes dites de moyennisation nous avons décrit l’approximation en grande population du nombre de cellules de chaque type. Nous avons également quantifié mathématiquement les grandes fluctuations biologiquement observées au niveau du nombre de globules rouges. Nous avons finalement construit un modèle pour comprendre l’influence des longues phases d’inactivité, connues, des cellules souches mutantes dans la production des globules rouges. Les cellules souches mutantes, en faible nombre dans l’organisme comparé aux cellules saines, basculent aléatoirement d’un état actif à un état inactif. Les différences d’échelle de taille entre les populations de cellules, nous a conduit à étudier la dynamique d’un processus de Markov déterministe par morceaux de dimension 4. Nous avons montré l’existence d’une unique probabilité invariante vers laquelle le processus converge en variation totale, et identifié cette limiteThis thesis focuses on understanding the mechanisms of stem cell differentiation leading to the production of red blood cells (a mechanism called erythropoiesis). To this end, we have developed different mathematical modelling leading to an understanding at different levels. Firstly, we have built and calibrated a model with 8 ordinary differential equations to describe the dynamics of 6 populations of cells in steady-state and stress erythropoiesis. The study of in vivo experimental data, realized by our collaborators St´ephane Giraudier (hematologist) and Evelyne Lauret (INSERM), showed the need of two equations to model erythropoiesis regulations. Modeling calibration was performed using biological data and a stochastic optimization algorithm called CMA-ES. This model highlighted the importance of the self-renewal capacity of the erythropoietic cells in the production of red blood cells. The development of a 3-dimensional probabilistic model then allowed us to understand the dynamic consequences of this capacity on the production of red blood cells. The study of this model required changes of scale in size and time revealing a so-called slow/fast system. Using averaging methods, we described the large population approximation of the number of each cell type. We have also mathematically quantified the large fluctuations in the number of red blood cells, biologically observed. Finally, we constructed a model to understand the influence of long periods of inactivity of mutant stem cells in the production of red blood cells. Mutant stem cells, which are in low numbers in the organism compared to healthy cells, randomly switch between an active and an inactive state. The different size scale between the cell populations led us to study the dynamics of a 4-dimensional piecewise deterministic Markov process. We showed the existence of a unique invariant probability measure towards which the process converges in total variation, and we identified this limits
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Gaston, Kevin A. "Morphometric variation of bluegill and green sunfish in lentic and lotic systems." 2012. http://liblink.bsu.edu/uhtbin/catkey/1678568.
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Adams, William J., John E. Toll, K. V. Brix, Lucinda Marie Tear, and D. K. DeForest. "Site-specific approach for setting water quality criteria for selenium : differences between lotic and lentic systems." 2000. http://hdl.handle.net/2429/9629.
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Results of an in-depth review of the literature indicates there are significant differences in the bioaccumulation of selenium by fishes and invertebrates from lotie (flowing) and lentic (standing) water
bodies and that selenate is much less bioaccumulative than selenite. Bioaccumulation in fish is a factor of 10 or more higher in lentic systems as compared to lotic systems. These differences are a function of selenium's site-specific biogeochemical cycling. Further, we observed considerable variation in bird accumulation of selenium from site to site. To account for differences in bioaccumulation potential of selenium we developed a residue-based Bayesian Monte Carlo model to derive site-specific selenium water quality criteria protective offish and sensitive avian species.
The approach uses data from a given site of interest to calibrate a model based on data from several other similar sites. When evaluating a specific site, the range of water and tissue concentrations is typically
limited. This makes it difficult to use site-specific data to identify a water concentration sufficiently low that tissue concentrations do not exceed the tissue-effect threshold. Data from several similar sites provide a broader range of water and tissue residue concentrations that allow for an appropriate statistical extrapolation of the data to the site of interest. The Bayesian Monte Carlo model accounts for the
significant site-to-site variability that exists in the relationship between water selenium and the mean tissue residue. In practice, data from similar sites are pooled to define a set of possible water and mean
tissue residue relationships. This set of possible: relationships is then used with data from the site of interest to determine which relationships, from the set of possibilities, best fit the specific site. Once we have determined which set of possible relationship's fit the specific site, we extrapolate from the observed water concentration to a water concentration that results in a tissue residue concentration less than or equal to a chronic effect threshold. This value becomes the chronic water quality criterion.
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"Effects of seed moisture and micronizing temperature on lentil flour properties and the stabilities of colour and unsaturated lipids of beef-lentil systems." Thesis, 2014. http://hdl.handle.net/10388/ETD-2014-06-1622.
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This study investigated the effect of seed moisture level of lentil and surface temperature of micronization (infrared heat treatment) on the physico-chemical and functional properties of resulting flours and how these flours affected colour and unsaturated lipid oxidation when incorporated into ground beef products. Flour from raw seed (non-tempered and non-micronized) was used as the control. Whole seeds of small green lentil (Lens culinaris L., var. Eston) without tempering (8% moisture) and tempered to 16% or 23% moisture was infrared heat treated (micronized) to 115, 130, 150 or 165 °C surface temperature. The decreased protein solubility (2-60%) and lipoxygenase (70-100%), peroxidase (32-100%) and trypsin inhibitory (up to 54%) activities of resulting flours indicated changes in the protein fraction due to heat-moisture treatment. Starch gelatinization was observed at the 23% moisture level and changes in pasting properties, and water and oil absorption capacities varied with treatment. The heat-moisture combinations modified properties of starch and protein to different degrees and, consequently, lentil flour functionalities. Incorporation of lentil flour as a binder in low fat (<10%) beef burgers at 6% (w/w) showed that flours from micronized lentil seeds enhanced retention of redness and suppression of lipid oxidation as indicated by Hunter a* values and thiobarbituric acid reactive substances values, respectively, in a retail display setting. Investigation of total phenolics in aqueous salt extracts of lentil flours showed a decrease in content with increased micronization temperature. The antioxidant assays showed no changes in the ferric ion reducing power or reduction of hydroxyl radical scavenging and superoxide radical scavenging activities with heat-moisture treatment. Reduction of lipoxygenase and peroxidase activities was evident in lentil flour aqueous salt extracts, and the enzyme activities were localized to seed cotyledons. The myoglobin-liposome model study showed that a flour extract from the 16% moisture and 150 °C treatment resulted in a slower rate of oxymyoglobin oxidation initiation than other treatments which had different levels of lipoxygenase and peroxidase activities. Unsaturated lipids accelerated oxymyoglobin degradation irrespective of the presence of lentil extract. The extended fresh red colour retention of ground beef due to addition of flours from micronized seed compared to that from non-micronized seed may be related to suppression of pro-oxidant activities and the activity of potential antioxidants. The putative antioxidative compounds in lentil that are available for meat components may include compounds other than lentil seed phenolics.
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"OPTIMISATION OF AGROBACTERIUM MEDIATED GENE TRANSFER AND MICROGRAFTING SYSTEMS IN LENTIL (LENS CULINARIS MEDIK)." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/2/12605460/index.pdf.
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"EFFECT OF SALT STRESS ON ANTIOXIDANT DEFENSE SYSTEMS OF SENSITIVE AND RESISTANT CULTIVARS OF LENTIL (Lens culinaris M.)." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/3/12605248/index.pdf.
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Raínho, Vera Mónica Ramos da Silva. "Preparação e Caracterização de membranas para lentes de contacto pós-cirúrgicas." Master's thesis, 2017. http://hdl.handle.net/10316/82866.
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Dissertação de Mestrado Integrado em Engenharia Química apresentada à Faculdade de Ciências e TecnologiaA eficiência da administração de fármacos na terapia ocular após intervenções cirúrgicas é um dos grandes fatores que condiciona a recuperação dos pacientes. Nos dias de hoje, a administração de fármacos nestes casos é realizada na forma de colírios. No entanto, este método mostra-se muito ineficiente, surgindo o uso de sistemas de libertação controlada de fármacos como uma possível alternativa bastante promissora. No decorrer deste trabalho foram desenvolvidas membranas à base de acrilatos para serem usadas como sistemas de libertação controlada de um fármaco (sob a forma de lentes de contacto), sendo o fármaco selecionada a moxifloxacina (MFX), um antibiótico muito utilizado no pós-operatório da terapia ocular. Estas membranas foram desenvolvidas através do método de polimerização na massa. Deste modo foram preparadas membranas com diferentes monómeros na sua constituição. Uma vez que o desconforto causado pela radiação solar é outro dos fatores que influencia a recuperação pós-operatória, com o intuito de minimizar este desconforto, também foram incorporados corantes fotocrómicos nas membranas desenvolvidas. A membrana com melhores propriedades, preparada a partir de acrilato 2-etil-hexilo (EHA), metacrilato de metilo (MMA), peróxido de benzoílo (BPO) e dimetacrilato de etilenoglicol (EGDMA), designada AMB 7, foi caracterizada e nela foi incorporada MFX e corantes fotocrómicos, por oclusão. Com base nesta formulação, foram desenvolvidas mais duas formulações, a ABM 7.1 e ABM 7.2, com o intuito de avaliar a influência do aumento do agente de reticulação EGDMA nas propriedades finais das membranas. Foi ainda preparada uma membrana incluindo na formulação o monómero metacrilato de 2-hidroxietilo (HEMA), designada ABM 10, com a finalidade de aumentar a hidrofilicidade da membrana. Nestas membranas, somente se incluiu MFX por oclusão.As membranas preparadas foram caracterizadas quimicamente por espectroscopia de infravermelho com transformada de Fourier (FTIR), confirmando o sucesso da polimerização. Através da análise termogravimétrica (TGA) constatou-se a elevada estabilidade térmica dos materiais, sendo superiores a 350ºC.Os ângulos de contato, a transmitância e o teor de água das quatro membranas selecionadas foram determinados. No que diz respeito a molhabilidade das membranas determinado pela medição do ângulo de contacto, a ABM 7 foi a que apresentou melhores resultados (45º), dentro do intervalo de valores de lentes de contacto comerciais. Quanto à transmitância, a ABM 7 confere um maior grau de proteção relativamente a radiação UV ao passo que a ABM 7.1, apresenta melhores resultados relativamente à sua transparência. As membranas que contem corantes fotocrómicos incorporados, foram as que apresentaram maior proteção a radiação UV, no entanto, a sua coloração resulta numa diminuição da transparência das membranas. Analisando ainda o teor de água, os valores obtidos foram inferiores a 2%, sendo a ABM 10 a membrana que apresentou a maior capacidade de absorção de água, um valor muito baixo para uma aplicação como lente de contacto. Os resultados da libertação da MFX nos três sistemas de libertação que foram estudados (ABM 7, ABM 7.2 e ABM 10), permitiram concluir que a membrana ABM 7.2 é a que apresenta melhores resultados, uma vez que apresenta um máximo de libertação ao final de quatro dias e apresenta o maior valor de massa libertada de moxifloxacina.
One of the main factors that determines the recovery of patients after ocular surgery interventions is based on the efficiency of drug administration. Nowadays, drug administration is usually made using eye drops. However, this system showed to be ineffective. Therefore, the use of ocular controlled drug delivery system is being used as an alternative. The present work is based on the development of new acrylate based membranes to be used as drug delivery systems in the form of soft contact lenses. Moxifloxacin (MFX) was the selected drug since it is an antibiotic widely used in ocular therapy. The membranes were prepared by bulk polymerization, using different monomers. The increase of sensibility to the solar radiation is one of the consequences after an ocular surgery. The incorporation of photochromics compounds in the acrylic based membranes was thus performed to diminish this discomfort. The membrane ABM 7 was developed based on 2-Ethylhexyl acrylate (EHA), methyl methacrylate (MMA), benzoyl peroxide (BPO) and Ethylene glycol dimethylacrylate (EGDMA), showed the best properties and was fully characterized since it showed the best properties. To study the influence of the crosslinking agent EGDMA in the final properties of the membranes, two other membranes based on ABM 7 were developed – ABM 7.1 and ABM 7.2. ABM 10 was prepared with 2-Hydroxyethyl methacrylate (HEMA) to enhance the hydrophilic character of the membrane. Only the best membranes – ABM 7, ABM 7.1, ABM 7.2 and ABM 10 – were selected for an extensive characterization and for MFX loading by occlusion. Photochromics incorporation was only performed in ABM 7. The membranes were chemical characterized by ATR-FTIR which confirms the polymerization reaction. Also, the thermal stability of the membranes was established, with Td higher than 377ºC, by TGA analysis. Water contact angles, transmittance and water content were also determined. ABM7 showed the lowest contact angle (44º), very close to the commercial soft contact lenses. Concerning the transmittance of ABMs, ABM 7 proved to have the higher capacity to protect the eyes form the UV radiation. On the other hand, ABM 7.1 was the most transparent membrane. For the membranes containing the photochromics, an enhancement of the protection of UV radiation was observed, however, the strong coloration of the membranes after UV exposure results in the loss of transparency. Concerning the water content of the membranes they were extremely low, having is highest value (2%) with ABM 10. The MFX release in ABM 7, ABM 7.2 and ABM 10 was studied and ABM 7.2 revealed to be the formulation with the maximum MFX release at the end of 4 days and with the higher amount of MFX released.
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Pinão, Sílvia Raquel Neves. "Development of membranes containing a controlled drug release system for ophthalmological applications." Master's thesis, 2016. http://hdl.handle.net/10316/81537.
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Dissertação de Mestrado Integrado em Engenharia Química apresentada à Faculdade de Ciências e TecnologiaA eficácia da administração de um fármaco depende muito da sua concentração no local a ser tratado, durante um período de tempo adequado. Hoje em dia, o método de administração de fármacos mais utilizado para muitas doenças oculares é a aplicação de colírios, embora este método seja muito ineficiente e pode levar a efeitos secundários indesejáveis. O uso de lentes de contacto como sistemas de libertação de fármacos é uma alternativa promissora, devido ao contacto prolongado com a superfície do olho, ao alto grau de conforto e à biocompatibilidade.Neste trabalho, foram desenvolvidas membranas para serem usadas como sistemas de libertação controlada de um antibiótico (moxifloxacina, MFX), partindo de quitosano e de poliacrilatos e utilizando os métodos de evaporação do solvente e de polimerização na massa, respectivamente. Três das membranas desenvolvidas foram seleccionadas para os estudos subsequentes e para carregamento de MFX: uma membrana à base de quitosano, contendo, também, gelatina, reticulada com glioxal e plastificada com poli(álcool vinílico) e poli(etileno glicol) (CBM 16) e duas membranas à base de poliacrilatos, uma preparada a partir de metacrilato de metilo (MMA), metacrilato de octadecilo (ODMA) e acrilato de 2-etil-hexilo (EHA) (ABM 4) e outra preparada a partir de MMA, ODMA, EHA e ácido metacrílico (MAA) (ABM 5). Também foi estudada a influência de uma modificação da membrana ABM 4 de três maneiras diferentes, por copolimerização enxerto utilizando radiação gama: (i) enxerto com metacrilato de 2-hidroxietilo (HEMA) empregando uma dose de radiação de 25 kGy (ABM 4.1); (ii) enxerto com metacrilato de N,N-dimetilaminoetilo (DMAEMA), empregando doses de radiação 25 e 15 kGy (ABM 4.2 e ABM 4.4, respectivamente) e (iii) enxerto com DMAEMA na presença de MFX, empregando uma dose de radiação de 15 kGy, com e sem um carregamento subsequente por soaking numa solução de MFX (ABM 4.3).Foi determinada a capacidade de inchaço, o ângulo de contacto com a água, os espectros vibracionais no infravermelho e a citotoxicidade das membranas. Os resultados mostraram que a membrana ABM 5 foi a que apresentou características mais semelhantes às de lentes de contacto comerciais.Introduziu-se MFX nas membranas mais promissoras quer por oclusão (O), quer por imersão (soaking; S), de modo a preparar sistemas de libertação controlada. Os resultados da libertação de MFX permitiram concluir que as membranas ABM 4 e ABM 5 carregadas por oclusão (ABM 4 – O; ABM 5 – O), foram as que apresentaram um maior tempo de libertação de fármaco (3 dias). Relativamente às membranas modificadas por enxerto empregando radiação gama e carregadas por imersão, concluiu-se que a membrana com o melhor resultado foi a ABM 4.4 - S, com 2 dias de libertação de fármaco e que a modificação por enxerto melhorou a libertação de fármaco quando este foi introduzido por imersão, mas piorou-a quando o fármaco foi introduzido por oclusão.
The effectiveness of drug administration strongly depends on attainment of an effective drug concentration in the area to be treated, for a sufficient period of time. Nowadays, the most used drug administration method for many eye diseases is delivery through eye drops, although it is very inefficient and can lead to negative side effects. The use of soft contact lenses as drug delivery systems appeared as a promising alternative, due to the prolonged contact with the eye surface, high degree of comfort and biocompatibility. In this work, membranes for controlled release of an antibiotic (moxifloxacin, MFX) were developed. They were based on chitosan and polyacrylates, employing solvent evaporation and bulk polymerization methods, respectively. Three of the developed membranes were selected for further study and loading of MFX: a chitosan-based membrane, which also contained gelatin, crosslinked with glyoxal and plasticized with poly(vinyl alcohol) and poly(ethylene glycol) (CBM 16), and two acrylate-based membranes, one prepared from methyl methacrylate (MMA), octadecyl methacrylate (ODMA) and 2-ethylhexyl acrylate (EHA) (ABM 4) and, the other, prepared from MMA, ODMA, EHA and methacrylic acid (MAA) (ABM 5). It was also studied the influence of a modification by gamma radiation-grafting of the ABM 4 membrane in three different ways: (i) grafting with 2-hydroxyethyl methacrylate (HEMA) employing a 25 KGy radiation dose (ABM 4.1), (ii) grafting with N,N-dimethylaminoethyl methacrylate (DMAEMA) employing 15 and 25 KGy radiation doses (ABM 4.2 and ABM 4.4, respectively), and (iii) grafting with DMAEMA in the presence of MFX, employing a radiation dose of 15 kGy, with and without subsequent loading of MFX by soaking (ABM 4.3).The swelling capacity, water contact angle, infrared vibrational spectra and cytotoxicity of these membranes were determined. The results showed that ABM 5 was the membrane most similar to commercial SCLs.MFX was introduced in the most promising membranes by occlusion (O) and soaking (S), in order to prepare drug release systems. The drug release results showed that membranes ABM 4 and ABM 5 loaded by occlusion (ABM 4 – O; ABM 5 – O), were the membranes that showed the highest drug release time (3 days). Relatively to the gamma radiation-grafted membranes loaded by soaking, the best result was obtained with ABM 4.4 - S, with 2 days of drug release and the modification by grafting improved the drug release duration when the drug was loaded by soaking, but worsened it when the drug was loaded by occlusion.
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Lenth, Christoph Alexander [Verfasser]. "Entwicklung eines Systems zur Kopplung eines Gaschromatographen mit einem mikrowelleninduzierten Plasma zur spektrometrischen Bestimmung von organischen Substanzen / Christoph Alexander Lenth." 2004. http://d-nb.info/969869436/34.
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Silva, Bruno Joel Ribeiro da. "Desenvolvimento de um Posto de Carregamento Lento com BMS e Interface com o Cockpit para o CEPIUM." Master's thesis, 2013. http://hdl.handle.net/1822/39835.
Full textAbstract:
Dissertação de mestrado integrado em Engenharia Eletrónica Industrial e de ComputadoresAtualmente, os veículos elétricos têm vindo a ganhar notoriedade dentro do ramo da indústria automóvel. Assim, existe um interesse crescente na substituição dos veículos com motor de combustão interna por veículos elétricos, devido às vantagens inerentes aos mesmos. No entanto, o desenvolvimento do veículo elétrico exige novas infraestruturas e soluções ao nível do carregamento, bem como novas soluções para o armazenamento de energia. O recurso às baterias para o armazenamento de energia nos veículos elétricos tem sido a solução mais adotada, assim, nesta dissertação descreve-se a implementação de um sistema de gestão e monitorização de baterias. Este sistema visa proteger as baterias contra abusos durante o seu funcionamento (não permite que os seus valores máximos e mínimos sejam excedidos), aumentando assim o seu tempo de vida útil, mas tentando sempre obter o melhor desempenho possível das baterias. Além disso, este sistema também informa o utilizador do veículo elétrico sobre diversos parâmetros do sistema de baterias, necessários para uma condução agradável e desprovida de ansiedade da autonomia, provocada pela falta de conhecimento do estado de carga das mesmas. Nesta dissertação, numa fase inicial apresenta-se o estado de arte sobre as tecnologias de baterias. De seguida, descreve-se a estrutura e constituição de um sistema de gestão de baterias. Posteriormente, realizam-se várias simulações para validar a topologia de equalização. Por último, implementa-se e testa-se o sistema de gestão de baterias proposto.
Currently, electric vehicles have been gaining notoriety within the field of car industry. Thus, there is a growing interest in the replacement of vehicles with internal combustion engine for electric vehicles, due to the inherent advantages of these. However, the development of the electric vehicle requires new infrastructures and solutions in what concerns loading, as well as new solutions for energy storage. The use of batteries for energy storage is the main solution adopted for electric vehicles. Thus, this work describes the implementation of a battery management system. This system aims to protect the batteries from abuse during operation (not allowing their maximum and minimum values to be exceeded), thereby increasing their lifetime, but always trying to get the maximum performance from the batteries. In addition, this system also informs the user of the electric vehicle about various parameters of the battery system required for a pleasant driving, and devoid of range anxiety, caused by the unawareness of the battery status. This work, initially presents the state of the art on battery technologies. Afterwards, describes the structure and constitution of a battery management system. Thereafter, several simulations are carried out to validate the topology of equalization. Finally, it presents the implementation and testing of the battery management system.
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Receveur, Garrett Wayne. "Commemorating Indiana at the 1916 Statehood Centennial Celebrations: An Examination of the Memory of Colonization and its Lingering Effects on the Indiana State Park System." Thesis, 2021. http://hdl.handle.net/1805/25311.
Full textAbstract:
Indiana University-Purdue University Indianapolis (IUPUI)Indiana’s state park system developed as a result of state centennial celebrations in 1916. Government officials created state parks as a permanent memorial that glorified the Hoosier pioneer spirit, which celebrated actions of white colonists as they confronted challenges of the new industrial twentieth century. However, this memorialization erased the Lenni Lenape, Miami, Potawatomi, and Shawnee tribes played in the state’s history. This paper analyzes the Indiana statehood centennial celebrations as sites of erasure of Native American contributions to state and national history. It examines how Richard Lieber, the founder of the parks system, and others built the state park system to understand the ways individual state parks commemorated that Hoosier pioneer spirit at the expense of Native American voices. Turkey Run, McCormick’s Creek, Clifty Falls, Indiana Dunes, Pokagon, Spring Mill, and Lincoln State Parks are critiqued in this analysis to illustrate how each park encompasses and presents the story of colonization.
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Tyler, John. "A Pragmatic Standard of Legal Validity." Thesis, 2012. http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10885.
Full textAbstract:
American jurisprudence currently applies two incompatible validity standards to determine which laws are enforceable. The natural law tradition evaluates validity by an uncertain standard of divine law, and its methodology relies on contradictory views of human reason. Legal positivism, on the other hand, relies on a methodology that commits the analytic fallacy, separates law from its application, and produces an incomplete model of law.
These incompatible standards have created a schism in American jurisprudence that impairs the delivery of justice. This dissertation therefore formulates a new standard for legal validity. This new standard rejects the uncertainties and inconsistencies inherent in natural law theory. It also rejects the narrow linguistic methodology of legal positivism.
In their stead, this dissertation adopts a pragmatic methodology that develops a standard for legal validity based on actual legal experience. This approach focuses on the operations of law and its effects upon ongoing human activities, and it evaluates legal principles by applying the experimental method to the social consequences they produce. Because legal history provides a long record of past experimentation with legal principles, legal history is an essential feature of this method.
This new validity standard contains three principles. The principle of reason requires legal systems to respect every subject as a rational creature with a free will. The principle of reason also requires procedural due process to protect against the punishment of the innocent and the tyranny of the majority. Legal systems that respect their subjects' status as rational creatures with free wills permit their subjects to orient their own behavior. The principle of reason therefore requires substantive due process to ensure that laws provide dependable guideposts to individuals in orienting their behavior.
The principle of consent recognizes that the legitimacy of law derives from the consent of those subject to its power. Common law custom, the doctrine of stare decisis, and legislation sanctioned by the subjects' legitimate representatives all evidence consent.
The principle of autonomy establishes the authority of law. Laws must wield supremacy over political rulers, and political rulers must be subject to the same laws as other citizens. Political rulers may not arbitrarily alter the law to accord to their will.
Legal history demonstrates that, in the absence of a validity standard based on these principles, legal systems will not treat their subjects as ends in themselves. They will inevitably treat their subjects as mere means to other ends. Once laws do this, men have no rest from evil.