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An Investigation of the Beam-Column and the Finite-Element Formulations for Analyzing Geometrically Nonlinear Thermal Response of Plane FramesSilwal, Baikuntha 01 May 2013 (has links)
The objective of this study is to investigate the accuracy and computational efficiency of two commonly used formulations for performing the geometrically nonlinear thermal analysis of plane framed structures. The formulations considered are the followings: the Beam-Column formulation and the updated Lagrangian version of the finite element formulation that has been adopted in the commercially well-known software SAP2000. These two formulations are used to generate extensive numerical data for three plane frame configurations, which are then compared to evaluate the performance of the two formulations. The Beam-Column method is based on an Eulerian formulation that incorporates the effects of large joint displacements. In addition, local member force-deformation relationships are based on the Beam-Column approach that includes the axial strain, flexural bowing, and thermal strain. The other formulation, the SAP2000, is based on the updated Lagrangian finite element formulation. The results for nonlinear thermal responses were generated for three plane structures by these formulations. Then, the data were compared for accuracy of deflection responses and for computational efficiency of the Newton-Raphson iteration cycles required for the thermal analysis. The results of this study indicate that the Beam-Column method is quite efficient and powerful for the thermal analysis of plane frames since the method is based on the exact solution of the differential equations. In comparison to the SAP2000 software, the Beam-Column method requires fewer iteration cycles and fewer elements per natural member, even when the structures are subjected to significant curvature effects and to restrained support conditions. The accuracy of the SAP2000 generally depends on the number of steps and/or the number of elements per natural member (especially four or more elements per member may be needed when structure member encounters a significant curvature effect). Succinctly, the Beam-Column formulation requires considerably fewer elements per member, fewer iteration cycles, and less time for thermal analysis than the SAP2000 when the structures are subjected to significant bending effects.
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BUCKLING AND POST-BUCKLING RESPOSNE OF SINGLE CURVATUE BEAM-COLUMNS UNDER THERMAL (FIRE) LOADSSOLTANI, GHULAM H 01 May 2017 (has links)
The main objective of this research was to study the buckling and post-buckling response of axially restrained beam-columns under thermal loading. Also the effects of slenderness ratios on pre-buckling and post-buckling behavior which is neglected in AISC specification was examined. The results of this study indicate that: a) Both the deflection and end moment amplification factors are significantly smaller for the restrained beam-columns subjected to temperature increase than the corresponding unrestrained beam-columns subjected to (mechanical) axial loads. b) The deflection amplification factors tend to decrease with decreasing ratio of end moments. However, reverse seems to occur for the moment amplification factors and as the moment amplification factors tend to increase with decreasing moment ratio particularly in the pre-buckling and the initial post-buckling range (0.1 < T/Tcr < 1.5). c) The thermal amplification factors tend to be smaller than the AISC values even in the pre-buckling range with those for the slender beam-columns significantly smaller than those for the shorter beam-columns.
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SYNERGISTIC APPLICATION OF A MUNICIPAL WASTE MATERIAL AND PHYTOREMEDIATION TECHNIQUE FOR REMEDIATING ACID MINE DRAINAGE AND IMPACTED SOILAckah, Louis A 01 August 2018 (has links)
Major impacts of current and pre-regulatory mining activities on the environment include the generation of acid mine drainage (AMD) and metal(loid)-laden acid sulfate soils. Current remediation techniques are mostly cost prohibitive due to high energy, material, and labor requirement. This study investigated two complementary low-cost methods that harnessed the metal(loid)-removing and acid-neutralizing properties of drinking water treatment residuals (WTRs) and the uptake (phytoremediation) potential of vetiver (Vetiviera zizanioides L.) and pokeweed (Phytolacca americana L.) to attenuate and immobilize metal(loid)s from natural AMD and metal(loid)-contaminated soil. Metals were removed from AMD by using a reverse flow fluidized column filter and hydroponic phytoremediation with vetiver and pokeweed. Metals were immobilized in soil through the amendment with Fe and Ca-WTR complimented by the uptake and translocation of metals by vetiver and pokeweed. Experiments were performed under controlled greenhouse conditions as well as under natural Illinois environment in simulated field conditions. Furthermore, the integrated effects of WTR application and the growth of vetiver on soil erosion were also studied. Physicochemical analysis of AMD and soil samples from the Tab-Simco abandoned mine in the Illinois Coal Basin, U.S.A, showed significant concentrations of major metals and metalloids such as Fe, Al, Mn, Zn, Ni, Cu and As at acidic pH levels. The degree of soil contamination at the site was spatially variable with respect to the location of the main AMD seep. Physical, chemical, agronomic and mineralogical characterization of locally acquired water treatment residuals (WTR) showed that the silty and alkaline (pH ≈ 7.0-9.1) materials also contained significant amounts of plant required micronutrients. The presence of amorphous phases of mostly metal (oxy)hydroxides, alkalinity, and porosity of the WTRs suggested the potential to neutralize acidity and capability to remove metal(loid)s in contaminated soils and AMD. Recorded metal removal (%MR) rate by WTR was rapid in the first 80 min in a batch agitation study, except for Mn. Thus, high metal removal ranging from 99.8% to 84.9% at selectivity sequence of Al>Fe>Cu>Zn and Mn (9.6%) was obtained at equilibrium. The pH of the AMD was also increased from 2.6 to 6.7. Analysis of leachate samples from gravity-drained columns following simulated rain events in a greenhouse study showed reduced concentrations of Al, Fe, Mn, Zn, Cu, As and Pb at sustained neutral pH compared with unamended control columns during the 12 weeks study period. Metal immobilization in soil by the lower amendment rates of WTR was comparable to the higher application rates and also showed lower oxalate extractability of metals. Tissue analysis of pokeweed and vetiver hyperaccumulators showed appreciable uptake of relevant elements although translocation was relatively low in both. The analytical results at the greenhouse scale was reproducible in a simulated field scale study under natural Illinois environmental condition where the best amendment rate including 50 g/kg Fe-WTR and 15 g/kg of Ca-WTR and manure helped to improve metal(loid) retention, soil structure and enhanced vetiver growth which subsequently aided in reducing the rate of erosion to levels comparable to bermudagrass which was used as control. The developed integrated WTR fluidized column and phytoremediation technique with vetiver and pokeweed under hydroponic conditions sequentially removed significant quantities of most heavy metals from AMD. Thus, the overall findings showed that the locally collected WTRs - the otherwise waste materials, showed high metal-removing and acidity-reducing capabilities in AMD and contaminated soil treatment applications. The similarity between the results obtained from the laboratory and simulated field study also showed that laboratory/greenhouse experiments may serve as reliable proxies for field responses in applications such as soil and water conservation in agricultural environments, remediation of abandoned mine lands, as well as wastewater treatment systems.
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Análise funcionalista da modalidade deôntica na coluna Confronto das Ideias do jornal "O Povo" / Functionalist analysis of deontic modality in "Confronto das Ideias" Column of "O Povo" NewspaperLopes, Maria de Fátima de Sousa January 2015 (has links)
LOPES, Maria de Fátima de Sousa. Análise funcionalista da modalidade deôntica na coluna Confronto das Ideias do jornal "O Povo". 2015. 147f. – Dissertação (Mestrado) – Universidade Federal do Ceará, Departamento de Letras Vernáculas, Programa de Pós-graduação em Linguística, Fortaleza (CE), 2015. / Submitted by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2016-03-28T13:27:46Z
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Previous issue date: 2015 / This study analyzes how linguistic expressions of deontic modality act in defense of points of view on texts from “Confronto das Ideias” column of a Brazilian newspaper called “O Povo”. We analyzed based on a functionalist view of language the manifestation of deontic modality in sixty texts produced over thirty topics each one with two contrary points of view. The topics covered in the column are about social issues of community interests. These texts were published in 2013 and 2014. Seen as the type of modality that is related to the possibility or need of acts performed by morally responsible agents, the deontic modality was analyzed in its syntactic, semantic and pragmatic aspects. With regard to the linguistic expressions of deontic modality, we verified that the modal auxiliaries were the most frequent of them with 62.7% of frequency. Among them, the auxiliary verb must was recurrent in establishing obligation, followed by the modal auxiliary can, that had an occasional frequency in establishing prohibition by negative polarity cannot. The obligation value was the most frequent with 65.9% of recurrence followed by permission value, often manifesting suggestions. With regard to semantic aspects, the deontic source that most introduced the modality was enunciator with 63.2% of frequency, since the authors, in most cases, speak on behalf of them and of a supposed common sense. The most common deontic target on which fall the deontic values was the common-area with 49.2% of presence in the texts. This type of deontic target relates to the whole community including the enunciator. When the target is defined by a third person, it was most frequent references to institutions. The tense in which the modal auxiliary verbs most appear was the Present, with 68.6% of frequency, and the Indicative, with 75.7% of recurrence. We conclude that the authors use these resources to present their ideas about obligations, permissions, suggestions and prohibitions related to topics of social interests. Some linguistic expressions were used to assert or attenuate the illocutionary force with which the authors defend their points of view, aiming to persuade the readers to practices presented by them as ideals. The deontic modality is therefore set as a category that introduces notions about conduct and citizenship in defense of points of view about social issues pointed in the column. / O presente estudo analisa de que maneira as expressões linguísticas da modalidade deôntica atuam na defesa de pontos de vista dos autores da coluna Confronto das Ideias do jornal O Povo. Pesquisamos, a partir de uma visão funcionalista da linguagem, a manifestação da modalidade deôntica em sessenta textos produzidos sobre trinta temas, cada tema com dois textos de posicionamentos contrários. Os temas tratados na coluna fazem referência a questões sociais, de interesse da comunidade. Os textos coletados foram publicados nos anos de 2013 e 2014. Vista como a modalidade relacionada à possibilidade ou necessidade de atos executados por agentes moralmente responsáveis, a modalidade deôntica foi aqui analisada quanto aos aspectos sintáticos, semânticos e pragmáticos. No que se refere aos meios linguísticos de expressão da modalidade deôntica, verificamos que os auxiliares modais foram os mais recorrentes, com 62,7% de frequência. Dentre eles, o verbo auxiliar dever foi constante frente aos demais, instaurando obrigação, seguido pelo auxiliar modal poder, que teve uma considerável frequência, instaurando proibição através da polaridade negativa não+poder. O valor de obrigação nos textos do corpus foi o mais frequente, com 65,9% de recorrência, seguido do valor de permissão, manifestado, muitas vezes, como uma sugestão. Com relação aos aspectos semânticos, a fonte deôntica que mais instaurou a modalidade foi a do tipo enunciador, com 63,2% de frequência, uma vez que os autores, na maioria dos casos, falam em nome deles e de um suposto senso comum. O alvo deôntico mais frequente, sobre o qual recaem os valores deônticos instaurados nesses textos, foi o domínio-comum, com 49,2% de presença nos textos. Esse tipo de alvo deôntico diz respeito a toda a comunidade, inclusive o enunciador. Quando o alvo é uma terceira pessoa definida, é mais frequente a referência a uma instituição. O tempo verbal em que os verbos auxiliares modais mais se manifestaram foi o Presente, com 68,6% de frequência, e o modo, o Indicativo, com 75,7% de recorrência. Concluímos que os autores se utilizam desses recursos para apresentar suas ideias com relação a obrigações, permissões, sugestões e proibições acerca de assuntos de interesse social. Algumas expressões linguísticas são usadas para asseverar ou atenuar a força ilocucionária com que os autores defendem seus pontos de vista, objetivando conquistar a adesão dos leitores às práticas apresentadas por eles como desejáveis. A modalidade deôntica é configurada, assim, como uma categoria que instaura noções relacionadas à conduta e à cidadania na defesa de opiniões sobre as questões de interesse social abordadas na coluna Confronto das Ideias do jornal O Povo.
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Modélisation de réacteurs Gaz-Liquide de type colonne à bulles en conditions industrielles / Modelling of gas-liquid bubble column reactors under industrial conditionsColombet, Damien 11 July 2012 (has links)
L’oxydation du cyclohexane est l’un des procédés les plus importants dans la chaîne de production du Nylon où l’oxygène et le cyclohexane entrent en contact pour former le cyclohexanol, la cyclohexanone puis l’acide adipique. Le rendement est influencé à la fois par le transfert de l’oxygène et par le mélange des réactifs en phase liquide. Des réacteurs de type colonne à bulles sont généralement utilisés pour fournir une aire interfaciale importante et garantir une agitation efficace en phase liquide. Cependant, la complexité des mécanismes impliqués (hydrodynamique, transfert, réaction, fort taux de vide) rend difficile la prédiction des performances des réacteurs. Ce travail est consacré à l’amélioration des lois de fermetures (quantité de mouvement et transferts) pour la modélisation Euler/Euler des réacteurs industriels utilisés pour le procédé d’oxydation du cyclohexane. Dans un premier temps, des expériences de laboratoire avec le système eau/air ont été réalisées jusqu’à de forts taux de vide (> 30%) pour mesurer les effets collectifs sur la force de traînée et le transfert de masse dans un essaim de bulles homogène. Les résultats ont confirmé que le coefficient de traînée des bulles augmente de manière significative avec le taux de vide alors que de manière surprenante l’effet est très faible sur le transfert. Dans un second temps, des expériences ont été réalisées avec le système cyclohexane/diazote dans des conditions industrielles (P = 1 - 20 bar, T = 30 - 150°C). L’analyse des résultats de transfert en condition industrielle a nécessité la simulation numérique directe du transfert à l’intérieur d’une bulle sphérique / Cyclohexane oxidation is one of the most important processes in the production line of Nylon, where oxygen and cyclohexane get in contact to produce cyclohexanol, cyclohexanone and then adipic acid. The production yield is influenced by both the oxygen transfer and the reactants mixing in liquid phase. Bubble column type reactors are usually used to provide a large interfacial area and efficient liquid phase agitation. However, the complexity of the mechanisms involved (hydrodynamic, transfer, reaction, high void fraction) makes it difficult to predict the performance of such reactors. This work is devoted to improve the associated closure laws of momentum and transfer equations used in Euler/Euler modelling of industrial reactors for cyclohexane oxidation. Bench-scale experiment for air-water system has been firstly carried out to measure the collective effects on the drag force and the mass transfer of a bubble in a homogenous bubble swarm with a high void fraction up to 30%. The results confirmed that bubble’s drag coefficient increases significantly with the void fraction. Meanwhile surprisingly, weak effect has been observed on the transfer. Nextly, pilot experiments with nitrogen-cyclohexane system have been performed under industrial conditions (P = 1 - 20 bar, T = 30 - 150°C). Analysis of the results of transfer under industrial conditions required finally direct numerical simulation of transfers inside a spherical bubble.
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Relação entre a postura estática do tronco e a flexibilidade da coluna vertebral e dos isquiotibiaisDucatti, Liliane Martini Araújo January 2016 (has links)
Tem sido apontado que tanto a avaliação da flexibilidade e/ou mobilidade corporal, quanto à avaliação da postura estática configuram um aspecto importante de ser observado antes de começar uma intervenção postural. Embora a flexibilidade seja primordial na estratégia para o movimento do corpo no espaço, ainda são incipientes as evidências acerca da relação entre a postura estática e a mobilidade da coluna vertebral. Visando fornecer subsídios para a compreensão dessa questão, a presente dissertação foi dividida em dois estudos: Estudo 1 – Objetivou investigar se existem evidencias de correlação entre flexibilidade e/ou mobilidade corporal com a postura estática. Esse estudo trata-se de uma revisão sistemática de estudos observacionais e ensaios clínicos randomizados e seguiu as recomendações da Colaboração Cochrane. Com as palavras chave “Static Posture”, “Flexibility” e “Mobility”, realizou-se uma pesquisa nas seguintes bases de dados: PubMed, Science, Embase e Bireme. Foram lidos na íntegra 51 estudos, após crivo dos critérios de elegibilidade (apresentação dos resultados do teste de correlação ou associação entre variáveis da postura estática e de mobilidade no plano sagital, evidenciando o grau e o sentido da relação). Destes, foram incluídos oito estudos, todos com alta qualidade metodológica, tendo a presente revisão forte força de evidência científica. Em linhas gerais, conclui-se que a presente RS apresenta evidências de que a flexibilidade corporal está relaciona com a postura corporal. E que apesar da maioria dos estudos incluídos concordarem entre si e apresentaram valores de correlação diferentes, estas diferenças podem ser explicadas devido à individualidade da flexibilidade corporal que irá apresentar padrões posturais diferentes Estudo 2 – A partir de uma amostra de 82 indivíduos, divididos em dois grupos (Padrão Postural Posterior - PPP e Padrão Postural Anterior - PPA), objetivou-se correlacionar as variáveis posturais estáticas (Padrões Posturais, ângulo das curvaturas dorsal, lombar e inclinação da pelve, também pulsão da pelve), obtidas pela avaliação postural estática no plano sagital utilizando a fotogrametria, com a flexibilidade da coluna vertebral e dos isquiotibiais nos movimentos de flexão e extensão mensurados pelo flexímetro. Na análise estatística foram utilizados os seguintes testes: teste de correlação Momento-Produto de Pearson, teste de correlação de Spearman, teste de correlação de Kendall’s tau-b, teste t independente ou o teste de Mann Whitney, teste t pareado e teste qui-quadrado. (<0,05). Na comparação entre os grupos, o grupo PPA apresentou valores significativamente maiores em relação ao grupo PPP para: ADM de Extensão da CV [t = 566,5, p = 0,011], Lordose Lombar (LL) [t (80) = 2,44, p ≤ 0,05] e Inclinação da Pelve (IP) [t (80) = 4,970, p≤0,001]; e valores significativamente menores para a Cifose Dorsal (CD) [t (80) = -5,99, p ≤ 0,001]. Quanto aos resultados de correlação, no grupo PPA houve correlação significativa e inversa entre a CD com a ADM de Extensão da CV (r=-0,34; p=0,027); e no grupo PPP houve correlação significativa e direta entre a CD com o Movimento de Flexão da CV (r=0,31; p=0,001), entre a CD com a ADM de isquiostibiais (r=0,26; p=0,044) e entre a LL com o Movimento de Flexão da CV (r=0,42; p=0,001) Com base nos resultados, conclui-se que para os indivíduos PPA existe correlação entre a Cifose Dorsal e a ADM extensão da CV e para os indivíduos PPP, entre a Cifose Dorsal e Lordose Lombar com o movimento de Flexão da CV e entre a Cifose Dorsal e a ADM isquiostibiais. Esses resultados sugerem que a postura estática das massas tórax – pelve, vista no PS, que é dado por padrões posturais anterior ou posterior à um eixo vertical, está relacionada com a flexibilidade e/ou mobilidade corporal. Logo, ao identificarmos um padrão postural que apresenta uma organização articular e muscular diferente na busca por posicionamento do corpo no espaço, pode-se ter uma melhor compreensão das possíveis restrições de movimento e assim direcionar melhor o tratamento fisioterapêutico postural. / It has been pointed out that both the assessment of flexibility and / or body mobility, and the evaluation of static posture constitute an important aspect to be observed before beginning a postural intervention. Although flexibility is paramount in the strategy for body movement in space, the evidence about the relationship between static posture and spine mobility is still incipient. In order to provide support for the understanding of this issue, the present dissertation was divided into two studies: Study 1 - The objective was to investigate if there is evidence of a correlation between flexibility and / or body mobility with static posture. This study is a systematic review of observational studies and randomized clinical trials and followed the recommendations of the Cochrane Collaboration. With the keywords "Static Posture", "Flexibility" and "Mobility", a search was carried out in the following databases: PubMed, Science, Embase and Bireme. A total of 51 studies were read following the eligibility criteria (presentation of the results of the correlation test or association between static and mobility variables in the sagittal plane, showing the degree and the meaning of the relationship). Of these, eight studies were included, all of them with high methodological quality, and the present review has strong evidence base. In general terms, it is concluded that the RS presents evidence that body flexibility is related to body posture. And although most of the included studies agree with each other and have different correlation values, these differences can be explained due to the individuality of the body flexibility that will present different posture patterns Study 2 - A sample of 82 individuals, divided into two groups (Posterior Postural Pattern - PPP and Anterior Postural Pattern - PPA), aimed to correlate the static postural variables (Postural Patterns, dorsal, lumbar and slope curvature angle Of the pelvis, also the pelvic drive), obtained by the static evaluation in the sagittal plane using the photogrammetry, with the flexibility of the spine and the hamstrings in the flexion and extension movements measured by the fleximeter. In the statistical analysis, the following tests were used: Pearson's Moment-Product correlation test, Spearman's correlation test, Kendall's tau-b correlation test, independent t-test or the Mann Whitney test, paired t-test, square. ( <0.05). In the comparison between the groups, the PPA group presented significantly higher values in relation to the PPP group for: CV Extension ADM [t = 566.5, p = 0.011], Lumbosarcoma (LL) [t (80) = 2, 44, p ≤ 0.05] and Pelvic Tilt (PI) [t (80) = 4.970, p≤0.001]; And significantly lower values for Dorsal Kyphosis (CD) [t (80) = -5.99, p ≤ 0.001]. Regarding the correlation results, in the PPA group there was a significant and inverse correlation between the CD with the CV Extension ROM (r = -0.34; p = 0.027); (R = 0.26, p = 0.044), and in the PPP group, there was a significant and direct correlation between the CD with the Flexion Movement of the CV (r = 0.31, p = 0.001) between the CD with the ischiatibial ROM And between the LL with the CV Flexion Movement (r = 0.42, p = 0.001) Based on the results, it is concluded that for PPA individuals there is a correlation between Dorsal Kyphosis and ADM extension of CV and for PPP individuals, between Dorsal Kyphosis and Lumbar Lordosis with CV Flexion movement and between Dorsal Kyphosis And ischiatibial ADM. These results suggest that the static posture of the thorax - pelvis mass, seen in PS, that is given by postural patterns anterior or posterior to a vertical axis, is related to flexibility and / or body mobility. Therefore, when we identify a postural pattern that presents a different articular and muscular organization in the search for positioning of the body in space, we can have a better understanding of the possible restrictions of movement and thus better target the postural physiotherapeutic treatment.
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Validade e reprodutibilidade do instrumento flexicurva para avaliação da flexibilidade da coluna torácica e lombarValle, Marja Bochehin do January 2017 (has links)
Pesquisadores têm buscado métodos confiáveis, não invasivos, práticos e de baixo custo para avaliar a flexibilidade da coluna vertebral. O instrumento Flexicurva consiste em uma régua de metal flexível coberta de plástico que moldado nas costas do indivíduo replica a forma da coluna vertebral. Alguns estudos propõem seu uso para avaliar a flexibilidade da coluna lombar no plano sagital, no entanto, a validade e a reprodutibilidade desse instrumento para a coluna torácica ainda não foi pesquisada. Neste contexto, essa dissertação apresenta dois estudos, cujos foram: (Estudo 1) identificar, a partir de uma revisão sistemática,quais são os métodos e instrumentos utilizados a para avaliar a flexibilidade da coluna vetebral torácica e lombar no plano sagital que apresentem validade e/ou repetibilidade e/ou reprodutibilidade confirmados, evidenciando seus respectivos índices psicométricos; (Estudo 2) avaliar se o Flexicurva é capaz de fornecer informações válidas e reprodutíveis para avaliação da flexibilidade de flexão e extensão da curvatura torácica e lombar. Para o Estudo1 foram realizadas buscas no banco de dados BIREME, EMBASE, PEDro, PubMed, Science Direct, SCOPUS e Web of Science, além de buscas manuais. Dois revisores independentes realizaram a seleção dos estudos, avaliaram a qualidade metodológica, o risco de viés e extraíram os dados. O sistema GRADE foi utilizado para avaliar a qualidade da evidencia. Foram incluídos 46 estudos, dos quais foram extraídos o número de participantes, o protocolo de avaliação e os índices psicométricos. Apenas sete estudos foram incluídos na análise quantitativa por meio de metanálise, suportando que há evidência científica apenas no que diz respeito à reprodutibilidade interavaliador do instrumento fita métrica no teste de Schöber modificado para o movimento de flexão lombar e a reprodutibilidade intra-avaliador dos instrumentos Flexicurva e sistema de análise de vídeo para os movimentos de extensão e flexão lombar. Para o Estudo 2, na avaliação da reprodutibilidade, 38 indivíduos tiveram a flexibilidade da coluna torácica e lombar avaliada nas posições em flexão e em extensão máximas. O molde com o Flexicurva foi realizado no mesmo dia, por três avaliadores (reprodutibilidade inter-avaliador); um avaliador realizou uma nova avaliação com um intervalo de sete dias (reprodutibilidade teste-reteste e intra-avaliador). Para avaliação da validade, 50 indivíduos foram avaliados com o Flexicurva e com o sistema de vídeo BTS Smart-DX (BTS Bioengineering, EUA) no primeiro dia, nas mesmas posições em flexão e em extensão máximasda coluna torácica e lombar. Os seguintes testes estatísticos foram utilizados: (1) para a validade: Coeficiente de Correlação Produto-momento de Pearson (r), Análise gráfica de Bland Altman, teste t independente e Erro RMS; (2) para a análise da reprodutibilidade teste-reteste, intra e interavaliador: ICC, SEM e MDC. (<0,05). Os resultados mostraram para a reprodutibilidade intraavaliador ICCs excelentes; reprodutibilidade teste-reteste ICCs de satisfatórios a pobre; e reprodutibilidade interavaliador ICCs satisfatórios para todas as variáveis. Os valores de SEM e MDC variaram de 0,9° a 8,3° e 0,4° a 16,3°, respectivamente. Quanto à validade do Flexicurva, encontrou-se correlação variando de excelente a fraca e erro RMS de 7,6° a 18,2°. Com base no Estudo 1, conclui-se que os resultados da revisão sistemática indicam baixa evidência científica sobre a validade, repetibilidade e reprodutibilidade dos 4 instrumentos e métodos indicados para a avaliação da flexibilidade da coluna vertebral torácica e lombar. Com base no Estudo 2,conclui-se que os resultados da reprodutibilidade devem ser vistos com prudência, devido aos altos valores de SEM e MDC, que indicam, em média, um erro de medida associado. Embora níveis aceitáveis de validade do Flexicurva tenham sido encontrados, sua utilização na flexão torácica e extensão lombar deve ser cautelosa. / Researchers have looking for reliable, non-invasive, practical and inexpensive methods to assess spine flexibility. The Flexicurve instrument consists of a flexible metal ruler covered in plastic and can be molded on the back of the individual, replicating the shape of the spine. Some studies propose its use to evaluate the flexibility of the lumbar spine in the sagittal plane, however, a validity and a reproducibility of this instrument for a thoracic spine has not been researched yet. In this context, this study presents two studies, which were: (Study 1) to identify, from a systematic review, the methods and instruments used to evaluate the flexibility of the thoracic and lumbar vertebral column in the sagittal plane that have confirmed validity and/ or repeatability and/ or reproducibility, evidencing their respective indexes psychometric; (Study 2) to access whether Flexicurve is capable of providing valid and reproducible information for assessing the flexibility of flexion and extension of the thoracic and lumbar curvature. For Study 1, searches were performed on BIREME, EMBASE, PEDro, PubMed, Science Direct, SCOPUS and Web of Science databases, as well as manual searches. Two independent reviewers selected the studies, assessed methodological quality, risk of bias, and extracted data. The GRADE system was used to evaluate the quality of the evidence. We included 46 studies, from which the number of participants, the evaluation protocol and the psychometric indexes were extracted. Only seven studies were included in the quantitative analysis by means of meta-analysis, supporting that there is scientific evidence only regarding the interobserver reproducibility of the metric tape measure instrument in the modified Schöber test for the lumbar flexion movement and the intra-observer reproducibility of the Flexicurve instruments and video analysis system for the movements of extension and lumbar flexion. For Study 2, in the evaluation of reproducibility, 38 subjects had the flexibility of the thoracic and lumbar spine evaluated at the positions of maximal flexion and extension. The model with Flexicurve was performed on the same day by three evaluators (inter-observer reproducibility); an evaluator performed a new evaluation with a seven-day interval (test-retest and intra-rater reproducibility). To evaluate the validity, 50 subjects were evaluated with the Flexicurva and BTS Smart-DX video system (BTS Bioengineering, USA) on the first day, in the same positions at maximal flexion and extension of the thoracic and lumbar spine. The following statistical tests were used: (1) for validity: Pearson's product-moment correlation coefficient (r), Bland Altman graphical analysis, independent t-test and RMS error; (2) for the analysis of test-retest, intra and inter-rater reproducibility: ICC, SEM and MDC (<0,05). The results showed for intra-observer reproducibility excellent ICCs; Reproducibility test-retest ICCs ranged from satisfactory to poor; and interobserver reproducibility ICCs was satisfactory for all variables. The SEM and MDC values ranged from 0,9° to 8,3° and 0,4° to 16,3°, respectively. Regarding the validity of Flexicurve, correlation was found ranging from excellent to weak and RMS error from 7,6° to 18,2°. Based on Study 1, it is concluded that the results of the systematic review indicate low scientific evidence on the validity, repeatability and reproducibility of the instruments and methods indicated for assessing the flexibility of the thoracic and lumbar spine. Based on Study 2, it is concluded that the reproducibility results should be viewed with caution, due to high SEM and MDC values, which indicate, on average, an associated measurement error. Although acceptable levels of Flexicurve validity have been found, its use in chest flexion and lumbar extension should be cautious.
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Adsorção de fármacos em carvão ativado : processo em batelada, leito fixo e modelagem das curvas de rupturaFranco, Marcela Andrea Espina de January 2018 (has links)
O presente trabalho estuda a remoção dos fármacos amoxicilina (AMX), diclofenaco sódico (DCF) e paracetamol (PAR) em solução aquosa pelos processos de adsorção em batelada e coluna de leito fixo utilizando o carvão ativado granulado (CAG) como adsorvente. Os experimentos foram realizados para cada fármaco de forma independente. Na adsorção em batelada foram avaliadas as influências do pH (2 – 10), concentração de adsorvente (5 – 20 g L-1) e tempo de contato (5 – 350 min). Foi realizada a investigação da cinética de adsorção e também do equilíbrio de adsorção através de isotermas nas temperaturas de 25, 35 e 45 ºC. A adsorção em leito fixo foi estudada através de planejamentos experimentais, onde foram avaliados os efeitos da concentração inicial do poluente (C0: 20 – 100 mg L-1), massa do leito (W: 0,5 – 1,5 g) e vazão (Q: 3 – 5 mL min-1) sobre o tempo de saturação (tsat) e a quantidade adsorvida (qsat). Os modelos de Thomas, Bohart-Adams e Yan, além de um modelo desenvolvido no software EMSO foram utilizados para análise das curvas de ruptura. O CAG utilizado apresentou área BET de 463 m² g-1 e maior volume de microporos, de 0,20 cm³ g-1. Os experimentos em batelada mostraram que o pH não teve influência significativa sobre a remoção dos três fármacos. O equilíbrio de adsorção da AMX e do DCF foi atingido após 150 min e do PAR após 180 min. O modelo de PSO foi o que melhor representou a cinética de adsorção dos três fármacos. A isoterma de Langmuir descreveu o equilíbrio da AMX a 25 e 35 ºC, e o modelo de Sips a 45 ºC. Já a adsorção do DCF foi representada pela isoterma de Freundlich e o PAR pela de Redlich-Peterson. O estudo termodinâmico indicou que a adsorção dos três fármacos foi espontânea e favorável, além de aumentar com o aumento da temperatura. Na adsorção em leito fixo, foi observado menores valores de tsat com o aumento de C0 e de Q e diminuição de W. Foi verificado que qsat aumentou com o aumento de C0 e diminuição da Q para o planejamento do PAR, onde essa variável foi significativa. Já o aumento de W aumentou qsat no planejamento do PAR e diminuiu nos casos da AMX e DCF. A AMX foi o poluente que apresentou os menores tempos de saturação, seguido do DCF e do PAR, na adsorção em leito fixo. Foi constatado que o modelo de Yan foi o que melhor reproduziu o comportamento das curvas de ruptura para os três fármacos, na comparação com os outros modelos analíticos e com o modelo numérico proposto no software EMSO. De forma geral, foi verificado que os processos de adsorção tanto em batelada quanto em leito fixo apresentam potencial de aplicação como alternativa de tratamento avançado de água e efluentes que contenham fármacos. / The present work studies the removal of amoxicillin (AMX), sodium diclofenac (DCF), and paracetamol (PAR) from water by adsorption onto granular activated carbon in batch process and fixed bed column. Batch adsorption experiments were performed to evaluate the influence of pH (2 – 10), adsorbent concentration (5 – 20 g L-1) and contact time (5 – 350 min). Pseudo-first order, pseudo-second order and intraparticle diffusion models were evaluated in the kinetics investigation. Equilibrium adsorption was investigated using Langmuir, Freundlich, Sips and Redlich-Peterson equations. Fixed bed adsorption was studied through experimental design to evaluate initial contaminant concentration (C0, 20 – 100 mg L-1), amount of adsorbent (W, 0.5 – 1.5 g) and feed flow rate (Q, 3 – 5 mL min-1) effects. The analytical models of Thomas, Bohart-Adams and Yan were selected to investigate the breakthrough curves behavior. In addition, a numerical model was developed and solved using EMSO software. The granular activated carbon (GAC) used had BET surface area of 463 m² g-1 and volume of 0.20 cm³ g-1 of micropores. The pH had no significant effect on the adsorption removal of the three drugs. Adsorption equilibrium of AMX and DCF was reached after 150 min and 180 min for PAR. Pseudo second order model best represented kinetic adsorption of the three compounds. At best conditions in batch process, adsorbent concentration was 12.5 g L-1 for AMX and DCF and 10 g L-1 for PAR. Langmuir isotherm best described AMX adsorption equilibrium at 25 and 35 ºC, and Sips model at 45 ºC. DCF and PAR adsorption followed the Freundlich isotherm and Redlich-Peterson model, respectively. Thermodynamic study indicated that the three drugs adsorption were spontaneous and favorable processes. In addition, adsorption increased at higher temperatures. In fixed bed adsorption experiments, saturation time (tsat) decreased with the increase of initial concentration and flow rate for both drugs. W had positive effect on tsat. The amount adsorbed (qsat) was enhanced at higher C0 and lower Q. qsat was higher at higher Q for AMX and DCF and lower Q for PAR adsorption. Yan model best reproduced breakthrough curves behavior for all drugs among the analytical models and the numerical model developed on EMSO software. Thus, adsorption processes in batch mode and fixed bed column showed to be effective for the removal of drugs of different therapeutic classes from water.
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Densidade mineral óssea de vértebras de ratos wistar suspensos pela cauda por 15 e 36 diasAntonietto, Eduardo [UNESP] 20 December 2010 (has links) (PDF)
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antonietto_e_me_araca.pdf: 362598 bytes, checksum: 31bb67971bee7c5aee6467cbcebf7a2a (MD5) / A suspensão de ratos pela cauda é modelo utilizado para investigar o comportamento ósseo em animais impossibilitados de se locomoverem. O osso é um tecido adaptativo que se desenvolve em sua estrutura e função, entre outros fatores, em resposta a forças mecânicas aplicadas a ele e demandas metabólicas que o mesmo venha sofrer. A ausência de forças mecânicas e de deformação óssea faz com que ocorra uma diminuição na deposição de cálcio por ausência de estímulos nos osteoblastos e osteócitos, favorecendo a ação dos osteoclastos, tornando o osso enfraquecido e quebradiço. Portanto, a ação mecânica é necessária para estimular a resposta óssea local e, assim, proporcionar seu crescimento e remodelamento. O objetivo deste estudo foi avaliar, através da densitometria radiográfica, se a suspensão pela cauda por 15 e 36 dias altera a densidade mineral óssea das vértebras cervical (C3), torácica (T6) e lombar (L1 e L3) de ratos Wistar. Trinta Rattus norvegicus albinus, adultos, machos, linhagem Wistar, massa corpórea média de ± 350g, foram divididos em 3 grupos: controle (n=10) - não suspenso; S15 (n=10) - suspenso por 15 dias e S36 (n=10) - suspenso por 36 dias. Para análise densitométrica as vértebras foram radiografadas, escaneadas, digitalizadas e analisadas pelo programa computacional ImageJ®. Houve aumento estatisticamente significante da densidade mineral óssea no grupo S15, provavelmente pela inquietação dos animais à suspensão, com diminuição no grupo S36, fato este hipoteticamente ligado à acomodação dos mesmos, concluindo que a suspensão pela cauda alterou a densidade mineral óssea num primeiro momento com diminuição com o passar do tempo / The suspension of rats by the tail model is used to investigate the behavior of bone in animals unable to move around. Bone is an adaptative tissue that develops in structure and function, among other factors, in response to mechanical forces applied to it and metabolic demands that it will suffer. The absence of mechanical forces and deformation of bone that occurs causes a decrease in calcium deposition in the absence of stimuli on osteoblasts and osteocytes, favoring the action of osteoclasts, making bones weak and brittle. Therefore, the mechanical action is necessary to stimulate local bone response and thus provide growth and remodeling. The aim of this study was to evaluable by radiographic densitometry, the tail suspension for 15 and 36 days alter the bone mineral density of cervical vertebrae (C3), thoracic (T6) and lumbar (L1 and L3) of Wistar rats. Thirty Rattus norvegicus albinus, adult, male, Wistar strain, average body mass ± 350g, were divided into 3 groups: control (n = 10) - not suspended; S15 (n = 10) - suspended for 15 days and S36 (n = 10) - suspended for 36 days. For densitometric analysis vertebrae were radiographed, scanned, digitized and analyzed by the computer program ImageJ ®. There was a statistically significant increase in bone mineral density in group S15, probably by the restlessness of the animals to the suspension, with a decrease in group S36, and this hypothetically is linked to the accommodation of the rats, concluding that the tail suspension altered bone mineral density in first time with a decrease over time
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“Fagulhas”: uma coluna de crônicas de Coelho Neto na Gazeta de Notícias (1897-1899)Venturelli, Vanessa Kitizo [UNESP] 29 January 2010 (has links) (PDF)
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venturelli_vk_me_assis.pdf: 2406280 bytes, checksum: bff6ec55ed6b3d0cf591df05639a8014 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho constitui-se da apresentação de 261 crônicas de Henrique Maximiniano Coelho Neto (1864-1934) publicadas na Gazeta de Notícias no período de 1897 a 1899. Estas crônicas trazem um rico repertório sobre a opinião do escritor em relação às turbulências sociais daquele período como a consolidação da república. Nas crônicas aqui estudadas, podemos acompanhar as frustrações do escritor antes dessa mudança tão significativa para os cariocas. As crônicas de Coelho Neto revelam um escritor atento a tudo o que acontecia no Rio de Janeiro, tanto em relação aos descuidos do governo com o saneamento básico e a criminalidade, como também em relação a problemas que afetavam a população e a vida cultural e literária: propaganda e dicas sobre concertos musicais, publicação de obras literárias, elogios, homenagens a homens das letras e apresentação de peças teatrais. Tudo isto foi encontrado neste conjunto de crônicas que, provavelmente, foi a contribuição de uma “fagulha” para os poucos cariocas alfabetizados daquele momento, mas que, com certeza, causou grande efervescência na opinião pública e governamental. Coelho Neto fazia seus leitores pensarem nas causas que precisavam de atenção e os provocava com sua palavra avassaladora, ora dissertativa, ora narrativa, mas sempre muito irônica. Muitos estudam as crônicas, como Brito Broca e Flora Süssekind, do período da Belle Époque brasileira, que foi a transformação definitiva do Rio de Janeiro segundo o modelo europeu; esta transformação teve como foco a estrutura da cidade, e os hábitos de conduta do povo carioca. O escritor, nomeado como “Príncipe dos Prosadores Brasileiros”, admirado... / This work is constituted of the presentation of 261 chronicles of Henrique Maximiniano Coelho Neto (1864-1934) published in the Gazeta de Notícias in the period from 1897 to 1899. These chronicles bring a rich repertoire on the writer's opinion in relation to the social turbulences of that period as the consolidation of the republic. In the chronicles here studied, we can accompany the writer's frustrations before such significant change for the cariocas. Coelho Neto's chronicles reveal an attentive writer to everything that happened in Rio de Janeiro, so much in relation to the government's negligences with the basic sanitation and the criminality, as well as in relation to problems that affected the population and the cultural and literary life: propaganda and clues on musical concerts, publication of literary works, praises, homages to men of the letters and presentation of plays. Everything this was found in this group of chronicles that, probably, it was the contribution of a spark for the few literate cariocas of that moment, but that, with certainty, it caused great effervescence in the public and government opinion. Coelho Neto made their readers to think in the causes that needed attention and he provoked them with his overpowering word, some times dissertative, other times narrative, but always very ironic. Many study the chronicles, as I Break Drill and it Adorns Süssekind, of Belle's period Brazilian Époque, that it was the definitive transformation of Rio de Janeiro according to the European model; this transformation had as focus the structure of the city, and the habits of conduct of the carioca people. The writer, nominated... (Complete abstract click electronic access below)
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