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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
491

Movimento de malhas e remalhamento de malhas superficiais / Mesh motion and surface remeshing

Igor Prata Soares 08 February 2007 (has links)
Malhas dinâmicas são comumente utilizadas em problemas de simulação sobre dominios cuja geometria varia com o tempo. Sempre que o domínio onde a malha está definida é alterado, as molas são acionadas movimentando os vértices para que estes se conformem com a nova descrição do domínio. Os tipos de molas mais utilizadas são: as longitudinais, as torcionais e as semi-torcionais. Nesta tese uma nova mola é proposta, a mola altura, que além de evitar sobreposição de elementos, é conceitualmente simples e fácel de ser implementada. Outra contribuição desse trabalho é o mecanismo de vértices ativos, que permite economia de processamento durante a resolução da malha dinâmica. Quando a fronteira do domínio sofre grandes alterações, o processo dinâmico pode não ter êxito na correção da malha. Para contornar esse problema, a fronteira deve ser alterada aos poucos. Uma nova estratégia para realizar grandes deformações em pequenos passos é introduzida nesta tese. Em algumas aplicações, o movimento da fronteira da malha pode comprometer células da própria fronteira. A correção da fronteira e um processo delicado, já que em muitos casos ele implica em alterar a descrição do domínio. Um novo método para efetuar a correção da fronteira é apresentado neste trabalho. Ele é baseado em malhas dinâmicas e utiliza um novo conceito de molas, as molas conservativas. Todas as contribuições citadas acima tiveram aplicação prática na industria aeronáutica, sendo utilizadas na implementação de uma metodologia inovadora para acoplar um simulador de escoamento de fluidos tridimensional com uma ferramenta de projeto inverso de aerofólios que roda em um contexto bidimensional. O outro assunto abordado e o remalhamento de triangulações superficiais. Foi proposto um novo método, chamado ANTS (Anisotropic Triangulations on Surfaces) que produz triangulações anisotrópicas de qualidade sobre superfícies descrevendo objetos com geometria complexa. O método ANTS é caracterizado por efetuar o remalhamento diretamente na triangulação inicial, isto é, ele não faz uso de qualquer tipo de parametrização, seja global ou local. O processo de remalhamento é feito por meio de quatro operadores: inserção, remoção e movimento de vértices e alternância de arestas. Os operadores de inserção e remoção de vértices possibilitam controlar a densidade de vértices no domínio, permitindo que nós sejam inseridos em regiões com densidade baixa ou eliminados onde a densidade é alta. A qualidade dos triângulos é controlada por meio dos operadores de movimento de vértices e de alternância (flipping) de arestas. O operador de movimento é utilizado no núcleo do processo de remalhamento. Para evitar que o remalhamento danifique a forma original da superfície, as quinas e os córneres são detectados no inicio do processo e preservados durante o remalhamento. A densidade de vértices sobre o domínio é controlada por uma função de espalhamento. Tal função pode ser passada como entrada para o ANTS ou calculada pelo próprio método. O ANTS foi aplicado com êxito em diversos exemplos gerando malhas de boa qualidade / This thesis intends to make a contribution on the field of dynamic meshes. Dynamic meshes are commonly used in the simulation of problems on domains whose geometry varies in time. Virtual springs are placed in the mesh to rearrange its vertices whenever the domain is changed. The most commonly used types of springs are: longitudinal, torsional and semi-torsional. In this thesis a new type of spring is introduced, the height spring, that is conceptually simple but produces good results. Another contribution of this thesis is the active vertices mechanism, that can improve the CPU processing time of the dynamic mesh. When the mesh domain undergoes large deformations, the proposed dynamic mesh algorithm may fail in correcting the mesh. A solution to this problem is perform large deformations in smal steps. A new strategy for this purpose is presented. Sometimes the motion of the mesh boundary can damage cells on the boundary itself. This is a trick problem to solve since the correction of boundary might change the domain geometry. A new method to correct the boundary cells is also presented in this study. The method is based on the dynamic mesh concept and uses a new type of spring, the conservative spring. All the mentioned contributions had been applied in the aeronautics industry. The techniques developed here has been used to implement an innovative methodology to couple a three-dimensional fluid dynamic solver with a two-dimensional inverse design tool for airfoils. This thesis also deals with remeshing. It is presented the ANTS, a practical method for remeshing anisotropic triangulations on surfaces of complex geometry. The method is capable of performing refinement and coarsening during the same process using the well-known remeshing operators: vertex motion, vertex deletion (by collapsing edges), vertex insertion, and edge flipping. An interesting feature is that vertex motion is used in the core of the process instead of in a post-processing smoothing step. The ANTS uses the input mesh as the geometrical description and works directly on the surface mesh without using any other auxiliary structure (besides the input mesh itself) to preserve the geometrical shape. Moreover, neither global nor local parameterization are applied. Sharp edges and points are identified at the beginning and kept during the process in order to preserve ridges and details. The method has been successfully applied to several examples producing high quality meshes
492

Taxa de alimentação para juvenis de pirapitinga criados em hapas / Feeding rate of youth for pirapitinga created in hapas

Zarpellon, Idayana 19 October 2015 (has links)
Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2016-03-10T18:32:43Z No. of bitstreams: 2 Dissertação - Idayana Zarpellon - 2015.pdf: 1299703 bytes, checksum: 695f80e09eb68cc4574a5e0bcd34a197 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-03-14T14:26:40Z (GMT) No. of bitstreams: 2 Dissertação - Idayana Zarpellon - 2015.pdf: 1299703 bytes, checksum: 695f80e09eb68cc4574a5e0bcd34a197 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-03-14T14:26:40Z (GMT). No. of bitstreams: 2 Dissertação - Idayana Zarpellon - 2015.pdf: 1299703 bytes, checksum: 695f80e09eb68cc4574a5e0bcd34a197 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-10-19 / This study was conducted in order to evaluate the effect of different feeding rates on growth performance, economic evaluation, morphometric characteristics and blood biochemistry of pirapitinga (Piaractusbrachypomus) in ponds during rearing. The experiment was conducted in the Fish Farming Sector of the Department of Animal Science School of Veterinary and Animal Science at UFG in the period from February to April, for 60 days. It was used 100 juveniles pirapitinga with an average weight of 328.81 ± 25.55 grams, randomly assigned in 20 hapas of 1 m³ installed in excavated tank of 200 m² in density of 05 juveniles / m³. The experimental design was randomized blocks, with five treatments, T1 0.7% of biomass; T2 1.4% of biomass; T3 2.1% of biomass; T4-2,8% of biomass; T5- 3.5% of biomass; with four replications, totaling 20 experimental units. Fish were fed with commercial feed containing 32% CP and grain size of 2-4 mm, twice a day, at 9 am and at 5 pm. The supply of feed was based on the percentage of biomass, so it was done a biometrics fortnightly from start to end of the experiment. The variables of productive performance were analyzed; economic evaluation; chemical composition of the carcass; blood chemistry ehistomorfometria gut: villi height. Data were subjected to analysis of polynomial regression and variance, and, in case of statistical differences, the average comparison test SNK (5%). The final individual weight and weight gain, showed a quadratic relation, in function of the increasing feed levels and their maximum points were checked feed rates de2,77% and 2.78% biomass per day, respectively. It was concluded that the feeding rate of 2.1% biomass per day resulted in a better performance and economic result and shorter ether extract to pirapitinga created during rearing in excavated tank. / Este trabalho foi desenvolvido com o intuito de avaliar o efeito de diferentes taxas de alimentação sobre o desempenho zootécnico, avaliação econômica, características morfométricas e bioquímica sanguínea da pirapitinga (Piaractus brachypomus) em tanques escavados durante a recria. O experimento foi conduzido no Setor de Piscicultura do Departamento de Zootecnia da Escola de Veterinária e Zootecnia da UFG no período de fevereiro a abril, com duração de 60 dias. Foram utilizados 100 juvenis de pirapitinga com peso médio de 328,81±25,55 gramas, distribuídos aleatoriamente em 20 hapas 1 m³ instaladas em tanque escavado de 200 m² na densidade de 05 juvenis/m³. O delineamento experimental utilizado foi blocos ao acaso, com cinco tratamentos, T1- 0,7% da biomassa; T2- 1,4% da biomassa; T3- 2,1% da biomassa; T4-2,8% da biomassa; T5- 3,5% da biomassa; com quatro repetições, totalizando 20 unidades experimentais. Os peixes foram alimentados com ração comercial contendo 32%PB e granulometria de 2-4 mm, duas vezes ao dia, às 9h e 17 h. O fornecimento de ração foi realizado com base na porcentagem da biomassa, por isso, foram realizadas biometrias quinzenais do início ao final do experimento. Foram analisadas as variáveis de desempenho produtivo; avaliação econômica; composição química da carcaça; bioquímica sanguínea e histomorfometria de intestino: altura de vilos. Os dados foram submetidos à análise de regressão polinomial e de variância, e, em caso de diferença estatística, ao teste de comparação de média SNK (5%). O peso final e ganho de peso individual, apresentaram relação quadrática, em função do aumento do nível de arraçoamento e seus pontos de máxima foram verificados com as taxas de alimentação de 2,77% e 2,78%, da biomassa ao dia, respectivamente. Conclui-se que a taxa de alimentação 2,1% da biomassa ao dia, proporcionou melhores desempenhos produtivos e econômicos e menor teor de extrato etéreo, para pirapitingas criadas durante a recria em tanque escavado.
493

Avaliação da associação entre obesidade e transtorno de déficit de atenção/hiperatividade em crianças e adolescentes / Evaluation of the association between obesity and attention deficit hyperactivity disorder in children and adolescents

Mariana Facchini Granato 09 October 2015 (has links)
O presente trabalho avaliou a associação entre duas condições clínicas de grande importância no contexto atual da pediatria: o Transtorno de Déficit de Atenção e Hiperatividade (TDAH) e a obesidade. O projeto foi desenvolvido com pacientes acompanhados no Instituto da Criança do Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP) e dividido em 2 braços. No primeiro, realizamos uma análise retrospectiva dos prontuários dos pacientes seguidos no ambulatório de Distúrbios de Aprendizagem com o intuito de estimar a prevalência de sobrepeso/obesidade em pacientes com diagnóstico de TDAH e comparamos tal prevalência com a de um grupo controle. Em seguida, avaliamos a influência do tratamento medicamentoso do TDAH (metilfenidato) no estado nutricional e estatura dos indivíduos. No segundo braço do estudo, avaliamos os pacientes seguidos no ambulatório de Obesidade a fim de estimar a prevalência de TDAH. A primeira etapa dessa avaliação, ocorreu por meio da aplicação do questionário SNAP-IV. Pacientes que tiveram uma triagem inicial positiva, foram encaminhados para a segunda etapa de avaliação, que consistiu em anamnese clínica e aplicação das seguintes ferramentas: Escala Wechsler de Inteligência para Crianças (WISC-IV), Escala Multidimensional de Ansiedade para Crianças (MASC) e Patient Health Questionnaire (PHQ-9). As análises estatísticas foram realizadas através dos testes \"qui-quadrado\" e teste \"T de Student pareado\". Ao final das coletas de dados, 93 pacientes com diagnóstico de TDAH foram incluídos no \"braço 1\" cujos resultados evidenciaram prevalência de sobrepeso/obesidade estatisticamente superior à observada no grupo controle (com p < 0,05). Na segunda etapa da avaliação, observamos que após o tratamento com metilfenidato (tempo médio de 2,6 anos) houve uma diminuição estatisticamente significativa (p < 0,01) no Z-score do IMC dos indivíduos, porém não foi observada influência estatisticamente significativa na estatura dos mesmos (p=0,30). Além disso, observamos que 42,1% dos indivíduos que estavam inicialmente nas faixas de sobrepeso/obesidade evoluíram com \"melhora\" do estado nutricional ao final do tratamento. No \"braço 2\" do estudo foram avaliados 103 pacientes, dos quais 37 (35,9%) apresentaram triagem inicial positiva para TDAH sendo convocados para a segunda etapa de avaliação. Desses, 26 participaram da segunda etapa, sendo 2 excluídos pois apresentaram déficit cognitivo. Em 15 pacientes foi confirmado o diagnóstico de TDAH (16,67%). As principais conclusões do trabalho são: (1) a prevalência de sobrepeso/obesidade em portadores de TDAH foi estatisticamente superior à observada na população geral; (2) o tratamento medicamentoso do TDAH não teve influência no crescimento estatural dos pacientes, independentemente do tempo de tratamento, mas promoveu uma redução no z-score de IMC dos indivíduos; (3) a prevalência de TDAH observada na amostra de pacientes portadores de obesidade foi estatisticamente superior à observada na população geral (16,7% - 95% IC 8,97-24,37% vs 5,29% - 95% CI=5,01-5,56%); (4) a presença de outras afecções como transtorno depressivo, transtorno de ansiedade e distúrbios do sono não foi significativa a ponto de explicar a associação entre TDAH e obesidade; (5) a ocorrência de ronco é bastante frequente em indivíduos obesos, tanto portadores quanto não portadores de TDAH. As principais limitações do estudo foram: (1) desenho retrospectivo do \"braço 1\"; (2) No \"braço 2\", 11 dos 37 pacientes que tiveram a triagem inicial positiva para TDAH não participaram da segunda etapa de avaliação. Além disso, seria interessante avaliar mais profundamente a ocorrência de distúrbios do sono (através da realização de polissonografia) e de alterações do processamento auditivo / The present study evaluated the association between attention deficit hyperactivity disorder (ADHD) and obesity, two clinical conditions currently of great importance in the field of pediatrics. The project included patients at the Children Institute of the HC-FMUSP (Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo), and were divided into two arms. In the first arm, we retrospectively analyzed the medical records of the ADHD patients at the learning disorder clinic to estimate the prevalence of overweight/obesity and compared this prevalence with that of a control group. Next, we evaluated the effect of ADHD drug treatment (methylphenidate) on nutritional status and height of the patients. In the second arm of the study, we examined the patients at the obesity clinic to estimate the prevalence of ADHD. The first evaluation step involved the use of the SNAP-IV questionnaire. Patients considered to have ADHD on initial screening were included in the second evaluation step, which comprised clinical history examination and the use of the Wechsler Intelligence Scale for Children, Multidimensional Anxiety Scale for Children, and Patient Health Questionnaire. Statistical analyses were performed using the chi-square and paired Student t tests. After data collection, 93 ADHD patients were included in arm 1; these patients showed a statistically higher prevalence of overweight/obesity than the control group (p < 0.05). During the second evaluation step, we found a statistically significant decrease (p < 0.01) in the BMI z-score of the individuals after methylphenidate treatment (mean duration of 2.6 years). However, there was no statistically significant effect on height (p=0,30). In addition, we found that 42.1% of patients who were initially overweight/obese evolved with improved nutritional status at the end of treatment. A total of 103 patients were evaluated in arm 2 of the study, among whom 37 (35.9%) found to have ADHD on initial screening were invited for the second evaluation step. Of these patients, 26 consented to participate in the second step. Two patients were excluded because they had cognitive impairment. ADHD was confirmed in 15 patients (16.67%). The main conclusions of the study were as follows: (1) prevalence of overweight/obesity among ADHD patients was statistically higher than that in the general population; (2) ADHD drug treatment did not affect the height of the patients, regardless of treatment duration, but caused a decrease in BMI z-score ; (3) prevalence of ADHD observed in the obese patient sample was statistically higher than that observed in the general population (16.7-95% CI 8.97-24.37% vs. 5.29- 95% CI=5.01-5.56%); (4) presence of other disorders such as depressive, anxiety, and sleep disorders was not sufficient to explain the association between ADHD and obesity; and (5) snoring is common in obese patients, both those with and without ADHD. The limitations of the study were as follows: (1) retrospective design of arm 1; (2) 11 of 37 patients in arm 2 diagnosed with ADHD on initial screening did not participate in the second evaluation step. Additionally, it would be interesting to further evaluate the occurrence of sleep disorders (using polysomnography) and auditory processing disorders
494

Estratégias de suplementação energética para bovinos em recria em pastagens tropicais durante as águas e seus efeitos na terminação em confinamento / Energetic supplementation strategies for growing cattle grazing tropical forages during the raining season and their effects on the feedlot finishing phase.

Luiz Roberto Dell Agostinho Neto 26 October 2010 (has links)
Os objetivos deste estudo foram avaliar estratégias de suplementação energética para bovinos em recria, mantidos em pastagens tropicais bem manejadas durante as águas, quanto ao desempenho animal, capacidade de suporte das pastagens, ganho de peso por área e desempenho dos animais durante a terminação em confinamento. Os tratamentos testados foram: T1) Controle: somente mistura mineral; T2) Constante: fornecimento contínuo do concentrado na dose de 0,6% do PC; T3) Crescente: fornecimento de 0,3% do PC em concentrado no primeiro terço, 0,6% do PC no segundo terço e de 0,9% do PC no terceiro terço do período de recria dos animais. Foram utilizados 76 garrotes de corte, com peso inicial de 208 kg e 8 meses de idade. Os animais foram alocados em 8,5 ha de pastagem de capim Brachiaria brizantha cv. Marandu, manejados em sistema rotacionado com intervalo de desfolha variável. Foram avaliadas a massa de forragem (MF) pré e pós pastejo (kg MS ha-1), a composição morfológica (% de folhas, colmos e material morto) e valor nutritivo da forragem, o ganho de peso individual (kg cab-1 dia-1), a taxa de lotação (cab ha-1) e o ganho de peso por área (kg ha-1) durante a fase de recria dos animais. Na fase de confinamento dos animais foram avaliados o ganho de peso diário individual (GPD em kg cab-1), o consumo de matéria seca (kg dia-1) e a eficiência alimentar dos animais (kg de ganho diário kg de alimento consumido-1).Os animais suplementados apresentaram GPD superiores aos animais não suplementados (0,535, 0,787 e 0,867 kg cab-1 dia-1, respectivamente para os tratamentos controle, constante e crescente). Além disso, os animais do tratamento crescente apresentaram desempenho superior àquele dos animais do tratamento constante, mesmo consumindo quantidades semelhantes de suplemento. A suplementação foi, ainda, eficiente em aumentar a taxa de lotação dos pastos que foi, em média, de 5,94, 7,13 e 6,90 UA ha-1, respectivamente para os tratamentos controle, constante e crescente. Durante a fase de confinamento, não houve diferença entre os tratamentos para GPD, que apresentou média de 1,06 kg dia-1. A suplementação energética de bovinos durante a fase de recria em pasto é uma estratégia eficaz para aumentar o GPD dos animais, a taxa de lotação das pastagens e a produção de carne por área de pasto. / The objective of this study was to evaluate the effect of strategies of feeding an energetic supplement to growing cattle, grazing well managed tropical pastures during the rainy season, on the grazing animal performance, pasture stocking rate, total body weight gain per area, and on feedlot finishing phase. The treatments tested were: T1) Control: animals fed only a mineral mixture; T2) Constant level: constant daily feeding of energetic supplement at 0.6% of BW; T3) Increased level: daily feeding of energetic supplement at increasing levels of 0.3, 0.6, and 0.9% BW, according to the experimental period. Seventy six beef steers, averaging 208 kg BW and 8 months of age, were used. Animals were allocated in a 8.5 ha area of Brachiaria brizantha cv. Marandu pasture under a rotational grazing system with a variable defoliation interval. Pre- and post-grazing forage mass (FM, kg MS ha-1), morphological composition (leaves, stem, and dead material percentages), nutritive value of the forage, average daily gain (kg animal-1 day-1), stocking rate (animal ha-1), and weight gain per area (kg ha-1) were evaluated during the growing phase. At the feedlot phase were evaluated the average daily gain (kg animal-1 day-1), dry matter intake (kg day-1), and the gain to feed ratio. Supplemented animals had greater ADG than animals not supplemented (0.535, 0.787, and 0.867 kg animal-1 day-1), respectively for the control, constant, and increasing treatment levels. Furthermore, animals in the increasing supplementation group presented a highest performance when compared to the constant supplementation, although animals from both treatments have consumed similar amount of supplement. Supplementation also was efficient in improving the pasture stocking rate, which averaged 5.94, 7.13, and 6.90 AU ha-1, respectively for the control, constant, and increasing treatment levels.During the feedlot phase, there were no ADG differences among any treatment, which averaged 1.06 kg day-1. DMI and feed efficiency were also not affected by supplementation strategies during the grazing phase.
495

Efeitos da exposição ao fumo durante a gestação nas medidas antropométricas dos recém-nascidos / Effects of passive tobacco exposure during pregnancy on anthropometric measurements of newborns

Schuh, Claudia Maria January 2008 (has links)
Objetivos: Diversos trabalhos documentaram a associação entre o fumo ativo na gestação e a redução no peso,comprimento e perímetro cefálico dos recémnascidos. Porém, existem controvérsias quanto aos efeitos do fumo passivo. Esse estudo buscou colaborar na elucidação sobre os efeitos da exposição da gestante ao fumo nas medidas antropométricas do recém-nascido. Métodos: Estudo transversal, que incluiu 200 parturientes, identificando a intensidade da exposição das mesmas ao fumo através da mensuração da cotinina urinária e do auto-relato sobre seu hábito tabágico e de seus familiares,o que possibilitou categorizá-las em não fumantes, fumantes passivas e fumantes ativas e posterior comparação com as medidas antropométricas dos recémnascidos. Resultados: Encontramos uma diferença estatisticamente significativa no peso,quando comparamos as fumantes passivas às não fumantes, -152g (IC95%: -285 a -18;P=0,026) e a diferença encontrada nas fumantes ativas foi de - 159g (IC95%: -301 a -16; P=0,029), em relação às não fumantes. Na medida do comprimento, observou-se uma diferença significativa entre as fumantes passivas, -0,8cm (IC95%: -1,4 a -0,2;P=0,012) em relação às não fumantes, e entre as fumantes ativas a diferença foi de -1,0cm (IC95%: -1,6 a -0,3;P=0,003), quando comparado às não fumantes. Quanto à medida do perímetro cefálico, não foram observadas diferenças significativas quando os grupos, das fumantes passivas e fumantes ativas, foram comparados ao grupo das não fumantes. Conclusões: Os resultados sugerem que o fumo passivo durante a gestação pode apresentar efeitos semelhantes aos do fumo ativo nas medidas antropométricas dos recém-nascidos. / Objectives: Several studies have documented the association between active smoking during pregnancy to weight, height and head circumference reduction on newborns. However, there are controversies about the passive smoking. The present study sough the elucidation of the effects of tobacco exposition of pregnant women on anthropometric measurements of newborns. Methods: Cross-sectional study, including 200 in labor women, identifying the intensity of their exposition to tobacco through the measurement of urine cotinine and the self reported information about the smoking habit of their relatives and themselves, what allowed us to classify them as non-smokers, passive smokers and active smokers and later the comparison with the anthropometric measurements of newborns. Results: We found a statistically significant difference in weight when comparing passive smokers to non-smokers, -152g (CI 95%: -285 to –18; P=0.026) and the difference found on active smokers was - 159g (CI 95%: -301 to 16; P=0.029) when compared to non-smokers. On the height measurements, a significant difference was found within the group of passive smokers, -0,8 cm (CI 95%: -1,4 to -0.2; P=0.012) comparing to the non-smokers group, within the smokers group the difference was -1,0 cm (CI 95%: -1,6 to -0.3; P=0.003) when compared to nonsmokers. About the measurements of head circumference, no was found a significant difference when the passive smokers and active smokers group was compared to non-smokers group. Conclusions: The results suggest that the passive smoking during pregnancy may present similar effects as the active smoking on the anthropometric measurements of newborns.
496

Altura de manejo do pasto e suas conseqüências sobre a produção animal e a dinâmica de pastagens anuais de inverno / Managemen sward height and his consequence in animal production and dynamics of anual winter pasture

Rocha, Lemar Maciel da January 2008 (has links)
O objetivo do experimento foi compreender e quantificar a mudança estrutural de pastagens anuais típicas do período hibernal do RS e avaliar o potencial produtivo e as características de carcaças de novilhos superprecoces. O experimento foi conduzido em área pertencente à Fazenda Espinilho, localizada no município de São Miguel das Missões – RS. Foram impostos quatro tratamentos por meio de diferentes alturas de manejo da pastagem: 10, 20, 30 e 40 cm, obtidas a partir da aplicação de diferentes cargas animais. O delineamento foi o de blocos completos casualizados com três repetições. Foram utilizados animais, com cerca de 10 meses de idade, machos inteiros, uniformes, sem padrão racial definido, com peso médio inicial de 190 kg. As variáveis estudadas foram: massa de forragem (MF), taxa de acúmulo de forragem (TAC), produção total de forragem (PTMS), relação lâmina foliar/colmo + bainha, ganho médio diário (GMD), ganho por área (GPA). Observou-se um aumento linear da MF com o aumento da altura do pasto, onde para cada cm de aumento na altura acima de 10 cm, correspondem um incremento de cerca de 108 kg/há na MF do pasto. Não houve efeito dos tratamentos para a TAC, bem como para a PTMS, cujos valores médios foram de 55,8 kg/há.dia e 8210 kg/ha, respectivamente. O aumento no GMD foi condicionado pelo incremento na qualidade e/ou na quantidade de forragem disponível, já que as OF diárias para os tratamentos de 10, 20, 30 e 40 cm de altura foram de 6, 7, 13 e 19 kg de MS/100 kg de PV, respectivamente. Portanto, o modelo de resposta do GMD em relação às alturas resultou em 0,96 e 1,24 kg/animal nos tratamentos de menor e maior GMD, respectivamente, que foram de 10 e 20 cm de altura. O maior GPA observado no tratamento 10 cm (515 kg de PV/ha) deveu-se à uma maior carga animal utilizada, e ambas apresentaram respostas lineares decrescendo com o aumento da altura de pastejo. O peso vivo dos animais antes do abate não foram incrementados com o aumento da altura do pasto (P>0,05). Houve um forte e abrupto decréscimo da relação lâmina/colmo+bainha colmo nos tratamentos 30 e 40 cm a partir de setembro. Investigou-se o ajuste de quatro tipos teóricos de distribuição das freqüências de altura em cada tratamento e em seis diferentes datas de observação, bem como o potencial de predição da MF por intermédio da altura do pasto. A distribuição das freqüências de altura se ajustou ao modelo Normal em apenas uma das noventa e seis séries analisadas. A distribuição tipo Gamma foi a que mais freqüentemente se ajustou aos dados de altura, porém, uma vez iniciado o pastejo, o incremento da heterogeneidade no pasto foi tal que a distribuição de freqüências não se ajustou a nenhum dos modelos estudados. Sugerese que as metas de altura de manejo devam ser variáveis ao longo do ciclo de pastejo, com o intuito de se administrar a heterogeneidade causada pelo animal. / Aiming to comprehend and quantify the structural changes in typical temperate annual pastures from RS and evaluate the potential production and characteristics of young beef steers carcass, this experiment was conducted at Fazenda Espinilho, located in São Miguel das Missões. Treatments were four sward height management targets (10, 20, 30 and 40 cm), using continuous variable stocking. A completely randomized block design with three replicates was applied. Beef steers weighting 190 Kg were used and they were ten months old, non-castrated males with no defined breed. The investigated variables were herbage mass (HM), herbage growth rate (GR), total dry matter production (TDMP) and laminae/stem+sheath relation, average daily gain (ADG), gain per area (GPA). Results indicated a linear increase relating herbage mass and sward height, where each cm on sward height above 10 cm increases herbage mass in 108 kg/ha. Treatments did not differ in GR and the TDMP, average values being 55,8 kg DM/ha and 8210 kg DM/ha, respectively. The increase on the average daily gain (ADG) was due to the increase of quality/amount of available forage and the herbage allowance for the treatments of 10, 20, 30, 40 cm, was 6, 7, 13, 19 DM kg/ 100 kg LW, respectively. So, the ADG was 0.96 and 1.24 kg/animal for the treatments of lowest and highest ADG, which corresponds to 10 cm and 20 cm. Once ADG was low, the highest GPA observed on the 10 cm treatment (515 Kg PV/ha) was due to a higher stocking rate and both presented a negative linear response, decreasing with the increase in sward height. Concerning final live weight there was no difference with increasing sward height (P>0,05). A pronounced decrease in laminae/stem+sheath relation for 30 and 40 cm treatments occurred by September. In addition, four theoretical distributions were fitted to sward height data for each treatment in six different sample dates. Sward frequency height distributions fitted Normal distribution only in one of ninety six data series analyzed. Gamma distribution was more frequently adjusted to sward height data, however, once grazing started, pasture heterogeneity was so increased that sward height did not fitted neither of the investigated models. It is suggested that sward height targets should be variable along the grazing season aiming to manage the heterogeneity caused by the animal.
497

Efeito de ondas em margens a jusante de dissipadores de energia por ressalto hidráulico

Gomes, Ana Paula January 2018 (has links)
Este trabalho apresenta um estudo experimental sobre o efeito da ação das ondas nas margens de rios que estão a jusante de estruturas hidráulicas. O trabalho foi realizado em três etapas, sendo a primeira realizada em modelo físico reduzido parcial de um vertedouro em degraus com canal a jusante, instalado no Pavilhão de Obras Hidráulicas (IPH/UFRGS). Nesta primeira etapa, diferentes condições de vazão e submergência foram consideradas, com o objetivo de avaliar as características das ondas de superfície, geradas a jusante de um dissipador de energia por ressalto hidráulico. As características avaliadas foram: altura, período, comprimento e celeridade das ondas. Os resultados dessa primeira etapa indicaram que as características principais das ondas, altura e período, estão mais relacionadas com a vazão escoada do que com a submergência do ressalto hidráulico. Além disso, através da comparação entre os dados estimados e observados da celeridade da onda, foi possível identificar que o período significativo da onda representa melhor a caracterização de uma onda que o período de pico, para ondas geradas a jusante de ressalto hidráulico. Na segunda etapa dos ensaios, as características das ondas obtidas na primeira etapa do estudo foram reproduzidas em um canal de ondas bidimensional, instalado no Pavilhão Fluvial (IPH/UFRGS). Desta forma, foi possível avaliar o efeito da ação das ondas sobre taludes com diferentes inclinações e granulometrias de material de proteção. Os resultados desta etapa demonstraram que o talude construído com material de proteção, denominado de brita grande (G) e com inclinação 1(V):3(H), foi o que apresentou maior estabilidade após a ação das ondas, mesmo sendo este um material de diâmetro médio menor do que o recomendado pelos métodos tradicionais de dimensionamento. Na terceira e última etapa dos ensaios, as características das ondas obtidas na primeira etapa do estudo foram reproduzidas novamente, porém em um tanque de ondas tridimensional, instalado no Pavilhão Fluvial (IPH/UFRGS). Nesta etapa do estudo, foi avaliado o efeito da ação das ondas sobre diferentes ângulos de incidência das ondas sobre talude de proteção. Os resultados obtidos nesta etapa demonstraram que o aumento do ângulo de incidência das ondas sobre o talude de proteção, intensifica o processo erosivo do material de proteção das margens. / This work presents an experimental study about waves action effects on the banks of rivers that are downstream from hydraulic structures. The work was carried out in three stages, being that the first one was realized in a reduced partial physical model of a spillway with steps and a channel downstream from it, installed in the Hydraulic Works Laboratory (IPH / UFRGS). In this first stage, different flow and submergence conditions were considered, with the objective of evaluating the characteristics of surface waves, that were generated downstream from a energy dissipator by hydraulic jump. The evaluated characteristics were: height, period, length and celerity of the waves. The results of this first stage indicated that height and wave period, considered the two main characteristics of waves, are more related to the outflow than to the submergence of hydraulic jump. In addition, through the comparison between the estimated and observed data of wave celerity, it was possible to identify that the significant period of wave represents better the characterization of a wave than the peak period, for waves generated downstream from a hydraulic jump. In the second stage of the tests, the wave characteristics obtained in the first stage of the study were reproduced in a two-dimensional wave channel, installed in the Fluvial Laboratory (IPH / UFRGS). In this way, it was possible to evaluate the effect of wave action on embankments with different inclinations and composed by protection material of diverses granulometries. The results of this experiment demonstrated that the embankment constructed with protective material called large gravel (G) and slope 1 (V): 3 (H) was the one that presented greater stability after the waves action, even though this material to has an average diameter smaller than that recommended by traditional dimensional methods. In the third and last stage of tests, the wave characteristics obtained in the first stage of study were reproduced again, but now in a three-dimensional wave tank installed in the Fluvial Laboratory (IPH / UFRGS). At this stage of the study, the effect of wave action on different angles of incidence between waves and the protective embankment was evaluated. The results obtained from this step demonstrated that the increase of the angle of incidence between wave and protective slope intensifies the erosive process of material that compose the banks.
498

Analysis of variation of mid-upper arm circumference and weight-for-height in children for the assessment of malnutrition in populations and individuals

Grellety Bosviel, Emmanuel 06 February 2019 (has links) (PDF)
Death from hunger and starvation can be avoided with appropriate diagnosis and treatment if the necessary knowledge and resources are available. The current definitions of acute malnutrition are based either upon a weight-for-height Z-score (WHZ) below -2 standard deviations of the international reference population (World Health Organization 2006 Growth Standards) or a mid-upper arm circumference (MUAC) lower than 125 mm. These indicators are used independently to define the sum of moderate and severe acute malnutrition, commonly referred to as global acute malnutrition (GAM). Severe acute malnutrition (SAM) is defined as the children with WHZ < -3 SD or MUAC <115 mm. These cut-off points are used both to estimate the prevalence of malnutrition and also to identify those children who should be admitted for individual treatment of their acute malnutrition.However, the ramifications of the new WHO standards and the introduction of the absolute MUAC as an additional criterion have not been sufficiently explored. There appears to have been little detailed analysis of the variation of MUAC in children using these new standards. Thus, there is insufficient information available for predicting changes in patient load due to the addition of an absolute MUAC cut-off, the degree of overlap between the criteria and the factors that affect the selection of malnourished children using the two criteria, WHZ and MUACNevertheless, because of the ease of use of MUAC and strong advocacy based mainly the relative sensitivity and specificity of WHZ and MUAC in predicting long-term all-cause mortality in the community, many organizations and some governments are now moving from using MUAC to screen children in the community and elsewhere to MUAC-only programs with abandonment of using WHZ altogether.A better understanding of the relationship between these measures is important as differences can have significant implications on the decision to intervene in a nutritional crises, assessment of potential program size, resource requirements and outcome, selection of children admitted for treatment and the strategy which will have the greatest influence upon mortality and the other poor outcomes of being malnourished. To this end my thesis included the following studies which explored the variation of MUAC and WHZ in children for the assessment of malnutrition.In my first study, I examined the direction and degree of discrepancy between MUAC and WHZ of children aged 6-59 months in 1,832 anthropometric surveys from 47 countries, mainly in Africa. The results show that using MUAC or WHZ, 16.3% of children were identified with GAM and 3.5% with SAM. The proportion of overlap between the two indicators was 28.2% for GAM (15-38.5%) and 16.5 % for SAM (6.1-29.8%). Overlap for individual countries was especially low for SAM. The numbers of children diagnosed by either criterion varied dramatically by country: the difference between the relative case-load using WHZ and MUAC for GAM varied from minus 57% to plus 72%. For SAM, in four of the 38 countries, less than 25% of severely malnourished children would be identified and admitted for treatment if a MUAC-only admission policy were being used. For all countries examined, the discrepancies were not adequately explained by any single hypothesis. My second study was in three parts. Each part examined the veracity of the assertion that MUAC is a better indicator of mortality than WHZ. 1) I analysed individual data from 76,887 children admitted to a range of treatment programmes to determine the mortality rates associated with SAM. 2) I conducted an exhaustive search of the literature to identify reports of children diagnosed by WHZ or MUAC with their respective mortality rates.3) I analysed the effect of case load using the prevalence data published in the first study with Case Fatality Rates (CFRs) derived from the empirical data, the literature data and theoretical simulations. We found that mathematical coupling caused a reversal of significance generating Simpson’s paradox so that the interpretation of the relative mortality rates of WHZ and MUAC is unsafe when children with both criteria are included in each group being compared. The analysis suggests that children with SAM identified by WHZ <-3 and admitted for treatment are at as least as high a risk of death as children in treatment with MUAC<115cm and probably at higher risk. Review of 21 datasets that compared WHZ and MUAC mortality rates show problems with interpretation of the reported CFRs in each of the studies; inconsistencies greatly limit analysis, comparability and interpretation. Caseload is a more important determinant of the number of SAM related child deaths than the relative CFR to give the number of SAM attributable deaths. Where most of the children are identified as SAM using WHZ, rather than MUAC, it is estimated that fewer than half of all SAM related deaths will be identified using a MUAC-only programme.In my third study, I have conducted a Monte Carlo simulation of anthropometric surveys and imposed random errors of measurement on the data in order to examine the effect of measurement error. The results show that there is an increase in the standard deviation with each of the errors, that the spread becomes exponentially greater with the magnitude of the sort of error that occur in real life situations and that the effect of an increase in standard deviation (SD) that appears to be fairly trivial has a major effect upon the reported prevalence of the condition. I show that even within quite a narrow range of SDs (from 0.8 to 1.2) the proportion of children <-2 WHZ can increase from 6% to 15% - which would move the population from one of “acceptable” prevalence to an acute emergency situation. The corresponding SAM would increase from about 1% to nearly 5%. If one was to use such a survey to estimate the current case-load of SAM children the difference would be five-fold. However, this range of SDs is generally thought to represent a “good survey”. When larger and more complex surveys are considered, for example those included in the WHO database or the DHS surveys, the SD is frequently greater than 1.2 leading to give a higher reported prevalence of malnutrition than may be the actual prevalence. In my fourth study, I performed a secondary analysis of the surveys collected in my first study in order to examine the change in reliability of such surveys over time. I analysed the statistical distributions of the derived anthropometric parameters from 1,843 surveys conducted by 19 agencies between 1986 and 2015. The results show that with the introduction of standardised guidelines and software by 2003 and their more general application from 2007 the mean standard deviation, kurtosis and skewness of the parameters used to assess nutritional status have each moved to now approximate the distribution of the WHO standards when the exclusion of outliers from analysis is based upon the SMART flagging procedure. Where WHO flags, that only exclude data incompatible with life, are used the quality of anthropometric surveys has improved and the results now approach those seen with SMART flags and the WHO standards distribution. Agencies vary in their uptake and adherence to standard guidelines. Those agencies that fully implement the guidelines achieve the most consistently reliable results.In conclusion, well-defined and internationally accepted criteria to assess anthropometric survey quality should be universally applied and reported if the surveys are to be reliable, credible and form the basis for appropriate intervention. Using WHZ-only or MUAC-only estimates of prevalence will underestimate the burden of acute malnutrition. Such a program policy would result in between 300,000 and 600,000 SAM deaths occurring in children each year who have no possibility of being treated. WHZ and MUAC are complementary indicators, it is only by using both criteria to identify SAM and admit children for treatment that we will move towards reducing avoidable SAM- related mortality in most countries. This will only be realised when we can conveniently identify children with a low WHZ in community screening programs. / Doctorat en Sciences de la santé Publique / info:eu-repo/semantics/nonPublished
499

Evaluating the East Java Tsunami Hazard: What Can Newly-Discovered Imbricate Coastal Boulder Accumulations Near Pacitan and at Pantai Papuma, Indonesia Tell Us?

Meservy, William Nile 01 October 2017 (has links)
Our paleotsunami surveys of the southern Java coast led to the discovery of five imbricate coastal boulder fields near Pacitan, Indonesia that may date to the mid-to-late 19th century or prior and two similar fields at Pantai Papuma and Pantai Pasir Putih that were tsunami-emplaced during the 1994 7.9 Mw event in East Java. Estimated ages for the fields near Pacitan are based on historical records and radiocarbon analyses of coral boulders. The largest imbricated boulders in fields near Pacitan and in East Java are similar in size (approximately 3 m^3) and are primarily composed of platy beachrock dislodged from the intertidal platform during one or several unusually powerful wave impactions. Hydrodynamic wave height reconstructions of the accumulations near Pacitan indicate the boulders were likely tsunami rather than storm-wave emplaced, as the size of the storm waves needed to do so is not viable. We evaluate the boulders as an inverse problem, using their reconstructed wave heights and ComMIT tsunami modeling to suggest a minimum 8.4 Mw earthquake necessary to dislodge and emplace the largest boulders near Pacitan assuming they were all deposited during the same tsunami event and that the rupture source was located along the Java Trench south of Pacitan. A combined analysis of historical records of Java earthquakes and plate motion measurements indicates a seismic gap with >25 m of slip deficit along the Java Trench. A 1000-1500 km rupture along the subduction interface of this segment is capable of producing a 9.0-9.3 Mw megathrust earthquake and a giant tsunami. However, evidence for past megathrust earthquake events along the this trench remains elusive. We use epicenter independent tsunami modelling to estimate wave heights and inundation along East Java in the event that the trench were to fully rupture. By translocating ComMIT slip parameters of Japan's 2011 9.1 Mw event along the trench offshore East Java, we demonstrate possible wave heights in excess of 20 m at various locations along its southern coasts. Approximately 300,000-500,000 people in low-lying coastal communities on the southern coasts of East Java could be directly affected. We recommend at-risk communities practice the "20/20/20 principle" of tsunami hazard awareness and evacuation.
500

EXPLORING ILLUSIONS OF HEIGHT IN SUIT DESIGN

Lee, Michael P. 01 January 2018 (has links)
Objective: The goal of this research was to explore how the design of clothing, specifically the design of the suit, can create height illusions. Background: Taller people enjoy many advantages, such as increased income and perceived attractiveness. These advantages motivate people to try to appear taller than they actually are, and clothing experts provide advice on how to accomplish this. However, there is little empirical evidence to validate the illusory effects clothing might have on overall height perception. The few studies that have explored illusions of body size created by clothing design have been limited in two important ways – the test stimuli have included unnatural body shapes and have failed to include naturalistic context (i.e., surrounding depth and size cues available in real scenes). Method: In the first phase, participants (nonexperts in clothing design) provided suggestions for how to appear taller by changing clothes. In the second phase, participants 1) viewed photographs of a variety of targets wearing suit designs that are commonly believed to manipulate viewers’ perceptions of height, 2) rated the targets on traits associated with height such as income and attractiveness, and 3) estimated the heights of these individuals. This study focused on the potential effects of suit color, specifically overall lightness (light vs. dark) and monochromaticity (monochromatic vs. lightness blocking). The effects of these designs were tested with and without contextual information by presenting targets within a natural streetscape or on a white background. Results: In the first phase, we found that nonexperts provided similar suggestions as experts in clothing design, including those pertaining to monochromaticity and lightness. In the second phase, we found that estimates were more accurate with more contextual information, and that clothing can impact height estimations, where monochromatic outfits yielded taller height estimates, although other outfit comparisons did not have effects. Outfits overall did not impact ratings such as income and attractiveness, although estimated height did correlate with these same social attributes. In an exploration of the impact of contextual and target-specific cues other than clothing on height estimations, we found that height perception was potentially dependent on a variety of factors such as the target's race, location (indoors vs. outdoors), stance, and the presence of nearby people. Scientific merit: This study increased our understanding of the conditions under which illusions of size in simple geometric stimuli generalize to the manipulation of size perception in real-world scenes. Broader impact: A better understanding of biases in height perception is relevant to domains in which such estimates are used to identify individuals (e.g., criminal justice) as well as domains in which visual characteristics of individuals are associated with errors in judgments of performance-based merit. (e.g., personnel selection and promotion).

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