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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.
221

A influência da variabilidade da intensidade e do exercício no treinamento de força para ganhos de força e área de secção transversa muscular / The influence of intensity and exercise variability in the gains of maximum strength and muscle cross section area in a strength training program

Rodrigo Monteiro da Fonseca 22 March 2011 (has links)
O objetivo desse estudo foi avaliar a influência da variabilidade da intensidade e do exercício no treinamento de força nos ganhos de força e área de secção transversa (AST). Quarenta e nove sujeitos destreinados e do sexo masculino foram divididos em cinco grupos: intensidade constante exercício variado (ICEV), intensidade constante exercício constante (ICEC), intensidade variada exercício variado (IVEV), intensidade variada exercício constante (IVEC) e controle (C). Foi realizado treinamento de força para membros inferiores durante doze semanas. A força máxima foi avaliada por meio do teste de uma repetição máxima (1RM) no agachamento e a AST do músculo quadríceps femural aferida por ressonância magnética. Todos os grupos obtiveram ganhos significativos em relação à condição pré-treinamento tanto de força máxima quanto de AST (P < 0,05). Não houve diferença significativa entre os grupos para ambas variáveis. A inclusão da variação do exercício isoladamente ou combinada com a variação da intensidade no estímulo do treinamento de força parece não trazer benefícios adicionais para o ganho de força e AST. Contudo, a variação da intensidade somente pode não ser a estratégia mais indicada quando o objetivo é gerar força em sujeitos destreinados em um período de doze semanas / The aim of this study was to evaluate the variability of intensity and exercise of the strength training on strength gains and muscle cross-sectional area (CSA). Forty-nine untrained male subjects were divided into five groups: constant exercise-varied intensity (ICEV), constant intensity-constant exercise (ICEC), varied exercise-varied intensity (IVEV), varying intensity- constant exercise (IVECO) and control (C). Strength training for the lower limbs was performed for twelve weeks. The maximal strength was assessed using the squat one repetition maximum test (1RM) and quadriceps femoris muscle CSA measured by MRI. All groups had significant gains both in maximum strength and CSA in relation to the pre-training (P <0.05). There were no significant differences between groups for both variables. On the IVEC group did not differ the maximum strength values from the control group at the post-test (P>0.05). The inclusion of the variation of exercise alone or combined with the variation in the stimulus intensity during a strength training program appears to produce no additional gains in strength and AST. However, the variation of intensity only may not be the best strategy when the objective is to increase strength in untrained subjects in a period of twelve weeks
222

Aparecimento de lesões decorrentes do desgaste ou não de dentes de leitões na maternidade: efeitos no comportamento e desempenho de suínos em diferentes fases da produção / Appearance of injuries resulting from detrition or no teeth piglets in maternity: effects on behavior and performance of pigs in different phases of production

Gisele Dela Ricci 26 June 2015 (has links)
O bem-estar animal tem sido foco de discussões referindo-se ao modo como os animais são tratados dentro dos confinamentos. A prática do desgaste dos dentes é realizada no segundo dia de nascimento dos lactentes, buscando reduzir lesões cutâneas nos leitões e no aparelho mamário das matrizes. O incorreto desgaste pode propiciar lesões e enfermidades que deprimem a imunidade e o desenvolvimento do leitão. Questiona-se, no entanto, a possibilidade de manter os dentes íntegros, uma vez que o corte e ou desgaste dos dentes podem aumentar a mortalidade na maternidade, reduzindo a habilidade do leitão em competir pelos tetos e consequentemente ganhar peso. A avaliação da estabilidade das instalações diante da qualidade de vida dos animais confinados tem recebido atenção notória nos últimos anos, surgindo à necessidade de analise do comportamento dos suínos diante dos procedimentos realizados nos primeiros dias de nascimento visando compreender e implantar aqueles que induzam ao menor sofrimento aos suínos contemplando simultaneamente o desempenho e bem-estar animal. Neste estudo foram avaliadas a presença e ausência de lesões nas faces dos leitões e nos tetos das matrizes a partir dos tratamentos de desgaste ou integridade dos dentes dos lactentes na fase de maternidade e a influencia destes tratamentos no comportamento, desempenho zootécnico e bem-estar de leitões e matrizes suínas durante as fases de maternidade, creche e pós-creche. Os dados foram analisados em delineamento inteiramente ao acaso com medidas repetidas no tempo. Utilizou-se o modelo misto com o efeito fixo de tratamento, data, período e suas interações; e o efeito aleatório de lote utilizando o procedimento MIXED do SAS (2008). Foi utilizado o teste de &chi;2 para avaliar o efeito de tratamento sobre a prevalência de leitões com lesões, escore médio de lesão por leitegada e essa variável foi analisada por meio da análise de medidas repetidas, usando também o PROC MIXED do Statistical Análises Sytem&copy;. Para os tratamentos empregados observou-se a apresentação de comportamentos típicos de animais confinados, no entanto, foram observadas importantes comportamentos relacionados a atividade mais intensa dos animais no momento da disputa pelos tetos nos primeiros dias de nascimento. Em relação ao desempenho notou-se a ausência de efeitos significativos no desempenho de matrizes suínas e leitegadas nos três locais avaliados, quando foi analisado o peso de entrada e saída setor de maternidade, de acordo com os tratamentos empregados. Para o desempenho na fase de creche, os tratamentos não demonstraram diferenças, entretanto, o efeito do local determinou diferenças significativas. Estes resultados sugerem que o procedimento de retirada dos dentes pode ser considerado desnecessário. Novos estudos realizados nesta área são necessários buscando elucidar a necessidade do procedimento de desgaste e prováveis efeitos subsequentes dentro das diferentes fases da criação. / The animal welfare has been focus of discussions referring to the way animals are treated within the confinements. The practice of wear on the teeth is performed on the second day of birth of the piglets, seeking to reduce skin lesions in piglets and breast apparatus of sows. Incorrect wear can provide injuries and diseases that depress immunity and the development of the piglet. Is discussed, however, the possibility of maintaining the integrity teeth once or cutting, and wear of teeth can increase mortality in maternity, reducing the pig&#39;s ability to compete for teats and consequently weight gain. Currently, it has been evaluated the stability of the installations on the quality of life of feedlot animals. Thus appear the need to analyze the behavior of the pigs on the procedures performed in the early days of birth in order to understand and implement those that lead to less suffering to pigs simultaneously considering performance and welfare. We evaluated the presence and absence of injuries on the faces of piglets and teats of sows from wear treatments or the integrity of the teeth of infants in the maternity phase and the influence of these treatments on behavior, animal performance and welfare piglets and sows during maternity phases, nursery and post nursery. Experimental design was conducted completely randomized with repeated measurements over time. We used the mixed model with fixed effect of treatment, date, time and their interactions; and the group of random effect using the MIXED procedure of SAS (2008). The &chi;2 test was used to assess the treatment effect on the prevalence of pigs with lesions, the mean score per litter injury and this variable was analyzed using repeated measures analysis using SAS PROC MIXED. For applied treatments was observed that the presentation of typical behavior of feedlot animals, however, were observed important behaviors related to more intense activity of animals at the time of competition for teats in the early days of birth. Regarding the performance was observed the absence of significant effects on the performance of sows and piglets at the three sites assessed, when we analyzed the input weight and output maternity phase, according to the treatments applied. For the performance in the nursery phase the treatments showed no differences, however, the effect of the local determined significant differences. These results suggest that the teeth of the withdrawal procedure can be considered unnecessary. New researches in this area are needed to elucidate the need to wear procedure and probable subsequent effect within the different phases of creation.
223

Wave propagation in flexible tubes

Feng, Jiling January 2008 (has links)
Wave dissipation was previously investigated intensively in the frequency domain, in which the dissipation of waves is described as attenuation of pressure pulse decay with respect to the frequency or harmonics. In this thesis, wave dissipation, including decay of pressure pulse, peak of wave intensity and wave energy, is investigated in the time domain using wave intensity analysis (WIA). Wave intensity analysis benefits to this research in several aspects including: 1) WIA allows for wave dissipation investigated in the time domain; 2) WIA does not make any assumptions about the tube's wall non-linearity and the analysis takes into account the effects of the vessel's wall viscoelastic properties, convective, frictional effects and fluid viscosity; 3) WIA offers a technique (separation) to study wave dissipation in one direction whilst taking into account the effect of reflections from the opposite direction; 4) The physical meaning of wave intensity provides a convenient method to study the dissipation of energy carried by the waves along flexible tubes. In this research, it is found that the degree of dissipation in flexible tube were not only affected by the mechanical properties of the wall property and viscosity of liquid but also by the other factors including initial pressure and pumping speed of piston as well as direction of wave in relation to direction of flow. Also an new technique to separate waves into forward and backward directions only using diameter and velocity might potentially be used to separate the waves in both directions non-invasively based on the non-invasive measurement of diameter (wall movement) available.
224

Streams of Blood and Water : A quantitative study on the effects of flood disasters on conflict intensity

Mauritz, Carl January 2017 (has links)
No description available.
225

Stretch intensity and the inflammatory response

Apostolopoulos, Nikos January 2015 (has links)
Background: Stretching may be viewed as an external/internal force influencing the range of motion of the connective tissue (muscles, tendons and the myotendon unit (MTU)) The magnitude and rate of stretching may potentially induce mechanical responses of the musculoskeletal system, such as increased range of motion (ROM). The degree of the intensity of stretch (low, medium, or high) may be used to optimize recovery from muscle damage via ameliorating inflammation; this is however, a plausible hypothesis that needs to be appropriately investigated. Aims: The present project aimed to investigate: 1) whether intense stretching (IS) causes an acute inflammatory response (study 1), 2) the effects of stretching intensity (low, medium, or high) in the onset of inflammation (study 2), and 3) investigate whether stretching intensity is responsible for aiding in the recovery of the muscle, post muscle damage (study 3). Methods: Studies one and two were randomized crossover trials consisting of 12 and 11 recreational male athletes, respectively. The former investigated whether high intensity stretching can cause an acute inflammatory response, with study two examining the effects of different stretching intensities (30%, 60% and 90%) based on a participant’s perceived maximum range of motion (mROM). Blood for both studies was collected at pre-, post, and 24h post intervention, and analyzed for high sensitivity C-reactive protein (hsCRP) (study 1 and 2), and for interleukin (IL)-1β, IL-6, and tumour necrosis factor (TNF)-α (study 1). In study three, a randomized controlled trial investigated whether stretching intensity (low or high), can influence the recovery from muscle damage. Thirty participants were randomized into three groups, a) low intensity stretching (LiS) (30-40% ROM), b) high intensity stretching (HiS) (70-80% ROM) and c) Control group. All participants performed both eccentric (EPT) and isometric peak torque (IPT) tests prior to a muscle damage protocol (MDP) (baseline). Participants were then assessed for EPT and IPT for three consecutive days post MDP. Soreness levels were recorded immediately post muscle damage and at 24, 48, and 72h, with blood samples collected at pre, 24, 48, and 72h post muscle damage and analyzed for Creatine Kinase (CK) and hsCRP. Results: Study one revealed a significant increase in hsCRP (P = 0.006) when comparing IS to Control condition, also confirmed by the effect size analyses. In study two, low (30% of mROM), and medium (60% of mROM) intensity stretching did not elicit an inflammatory response while a pronounced inflammatory response was observed when comparing 30 to 90 and 60 to 90% mROM. In study three, LiS showed a significant increase in EPT compared to both HiS and Control, and these findings were confirmed by magnitude based inferences analyses (i.e. LiS was associated with a positive effect for both IPT and soreness levels compared to Control and HiS). Blood biomarkers were associated with inconsistent effects compared to Control and HiS for all three-time periods. Conclusions: This thesis provides preliminary results suggesting that increased stretching intensity may be responsible for causing an acute inflammatory response. In addition, it was observed that LiS might be associated with faster recovery from muscle damage with respect to muscle function (EPT and IPT) and soreness levels. More research is needed to investigate these findings further.
226

Freshwater Wetland Creation in a Changing Urban Environment: Designing for Long-Term Viability

Brown, Aaron Thomas Ryan 14 July 2017 (has links)
Urbanization and wetland mitigation are increasingly common in coastal watersheds with expanding populations. These mitigation wetlands are intended to offset the functional and structural losses experienced when natural systems are degraded or destroyed. In the Tampa Bay watershed, urbanization is both expanding into the upper reaches of the watershed and intensifying in previously-developed areas, resulting in the creations of hundreds of freshwater mitigation wetlands. This dissertation utilized an existing database of mitigation wetlands, publicly available data, and field surveys to investigate the relationship between constructed wetlands and their surroundings and also determine how design affects wetland condition over time. The overarching goals of this dissertation were to evaluate the geospatial distribution and areal extent of constructed freshwater mitigation wetlands in Hillsborough County and determine how they influence the landscape; evaluate design variables and environmental factors influencing constructed wetland trajectories; and determine how future changes to the landscape will likely affect constructed wetland systems. The goals of Chapter 2 were to evaluate the relationship between mitigation wetland construction and total freshwater wetland area; determine if forested and non-forested wetlands are being impacted/mitigated at similar rates; determine if wetland mitigation is offsetting impacts from increased urbanization at the landscape scale. This study concluded that since 1985, permitted impacts of non-forested wetlands have occurred at a significantly greater annual rate than forested systems, despite their smaller regional footprint. Interestingly, this increased impact frequency, combined with mitigation ratios greater than 1:1 (mitigation to impact area), have helped decrease proportional difference in area between forested and non-forested wetlands in the region. Over the period of the study, mean LDI scores for drainage basins across watershed have increased, with those containing mitigation projects significantly increasing compared to those without. Changes in drainage basin LDI were significantly correlated to the number of mitigation projects per basin, total impact area, and total mitigation area. Upward shifts in drainage basin LDI categories have been documented in 25 of Hillsborough County’s 184 basins, however no significant connection to permittee-responsible freshwater wetlands was established. These results imply that current mitigation practices are failing to ameliorate increasing development intensity at the landscape scale. The goals of Chapter 3 were to determine the current condition of created freshwater mitigation wetlands in Hillsborough County, Florida; determine if forested and non-forested wetlands maintain similar trajectories after release; and evaluate how design and changes in the landscape influence created wetland condition over time. Original wetland engineering plans and historical data were used to establish baseline conditions at the time of wetland “release” and track wetland changes over time. A chronosequence approach was utilized to determine wetland trajectories and analyze potential differences between forested and non-forested systems. This study found that surveyed freshwater wetlands had decreased in size from their intended area by a total of approximately 18%, but due to increased mitigation ratios, were likely still producing a net gain in total wetland area and meeting the goals of “no net loss”. On average, wetland condition (as determined by WRAP scores) decreased by 9% from the time of release to the time of survey. Few differences were observed between wetland types with the exception of canopy richness and wetland trajectory, although correlations between wetland condition and time were non-significant. From the regression optimization analyses, it appeared that wetland location (as measured in the design WRAP score) was one of the most important factors contributing to surveyed wetland condition. In Chapter 4, future land use data was used to determine predicted anthropogenic pressure on these urban wetland systems and evaluate changes to the overall landscape. GIS based analyses on landscape development intensity (LDI) determined that significant changes are not expected at the landscape scale by the year 2025, however drainage basins that possess mitigation wetlands are anticipated to increase in development intensity. Predicted LDI scores for constructed freshwater wetlands is predicted to increase significantly, which could have detrimental impacts on wetland condition. This dissertation highlights the significance of wetland design and location on wetland condition. From this research, it is apparent that consideration of site placement is the most important design variable for small (3 hectares or less) freshwater wetlands; and that understanding of future conditions may promote long-term success. Long-term studies such as this are valuable tools for understanding how specific ecosystems respond to changing landscapes and should be used to help shape policies that reflect these ecological advancements. Understanding the past and preparing for the future is the only way to foster restoration success.
227

Mixed integer programming with dose-volume constraints in intensity-modulated proton therapy

Zhang, Pengfei, Fan, Neng, Shan, Jie, Schild, Steven E., Bues, Martin, Liu, Wei 09 1900 (has links)
Background: In treatment planning for intensity-modulated proton therapy (IMPT), we aim to deliver the prescribed dose to the target yet minimize the dose to adjacent healthy tissue. Mixed-integer programming (MIP) has been applied in radiation therapy to generate treatment plans. However, MIP has not been used effectively for IMPT treatment planning with dose-volume constraints. In this study, we incorporated dose-volume constraints in an MIP model to generate treatment plans for IMPT. Methods: We created a new MIP model for IMPT with dose volume constraints. Two groups of IMPT treatment plans were generated for each of three patients by using MIP models for a total of six plans: one plan was derived with the Limited-memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) method while the other plan was derived with our MIP model with dose-volume constraints. We then compared these two plans by dose-volume histogram (DVH) indices to evaluate the performance of the new MIP model with dose-volume constraints. In addition, we developed a model to more efficiently find the best balance between tumor coverage and normal tissue protection. Results: The MIP model with dose-volume constraints generates IMPT treatment plans with comparable target dose coverage, target dose homogeneity, and the maximum dose to organs at risk (OARs) compared to treatment plans from the conventional quadratic programming method without any tedious trial-and-error process. Some notable reduction in the mean doses of OARs is observed. Conclusions: The treatment plans from our MIP model with dose-volume constraints can meetall dose-volume constraints for OARs and targets without any tedious trial-and-error process. This model has the potential to automatically generate IMPT plans with consistent plan quality among different treatment planners and across institutions and better protection for important parallel OARs in an effective way.
228

Analyse et optimisation des performances de la technique VMAT pour son utilisation en radiothérapie / Analysis and optimisation of performance of the VMAT technique for its use in radiotherapy

Lafond, Caroline 15 November 2013 (has links)
La technique de radiothérapie VMAT (Volumetric Modulated Arc Therapy), diffusée en 2009, combine les avantages des techniques d'arc thérapie dynamique aux avantages des techniques de radiothérapie conformationnelle avec modulation d'intensité (RCMI) par faisceaux stationnaires. L'objectif de la thèse est de rendre optimales les conditions de mise en œuvre du VMAT autour d'un accélérateur linéaire d'électrons Synergy/Elekta afin de sécuriser la technique et de pouvoir bénéficier de l'apport clinique potentiellement attendu. Sur la base d'une analyse de l'influence des différents paramètres de la chaîne de traitement, nous proposons des éléments d'optimisation du traitement à la fois sur la planification dosimétrique et sur le contrôle de son exécution sur la machine. Nous montrons que si la qualité de l'optimisation de la technique dépend des caractéristiques intrinsèques de l'accélérateur, elle est également fortement influencée par le paramétrage du système de planification des traitements (TPS). Nous mettons en évidence des différences comparées des collimateurs Beam Modulateur (largeur de lames de 4 mm) et MLCi2 (largeur de lames de 10 mm) tant sur le plan de la distribution de dose obtenue que sur l'efficience. Nous montrons que, si pour deux principaux TPS commercialisés (Pinnacle/Philips et Monaco/Elekta) les distributions de dose aux volumes cibles sont peu modifiées, les différences de méthodes implémentées influencent la distribution de dose aux tissus sains. Nous proposons des programmes de contrôles de qualité au niveau de l'accélérateur, des plans dosimétriques de traitement et de l'exécution des traitements. Afin de garantir un niveau de confiance élevé sur la dose délivrée, nous proposons une méthode d'évaluation de la fluence délivrée en cours de traitement basée sur l'analyse des paramètres machines. Nous établissons que le processus de traitement VMAT optimisé fournit des performances de qualité supérieure que les techniques de RCMI par faisceaux stationnaires pour quatre localisations tumorales majeures étudiées. / VMAT (Volumetric Modulated Arc Therapy) technique has been introduced in 2009, it combines advantage of arctherapy techniques with advantage of IMRT (Intensity Modulated Radio Therapy) techniques delivered with stationary beams. The purpose of the thesis is to optimise implementation conditions of VMAT for a Synergy/Elekta linear accelerator in order to secure the technique and to be able to benefit from potentially expected clinical improvement. From analysis of influence of various work flow parameters, we propose treatment optimisation factors both on dosimetric planning and on delivering control on the accelerator. We show that if optimisation quality depends on intrinsic accelerator characteristics, it also depends very much on configuration of treatment planning system (TPS). We highlight compared differences between Beam Modulateur (leaf width of 4 mm) and MLCi2 (leaf width of 10 mm) on dose distribution and on efficiency. We show that if differences of dose distributions are small for two major TPS (Pinnacle/Philips and Monao/Elekta), the differences of implemented methods affect dose distribution of healthy tissues. We suggest quality control set for accelerators, for treatment plans and for treatment delivery. In order to provide a high safety level on delivered dose, we suggest an evaluation method of the real fluence provided during treatment delivery by analysing accelerator parameters. We establish that optimised process of VMAT treatment provides better performance than RCMI techniques delivered with stationary beams for the four major cancer cases that has been studied.
229

Frequency and Intensity Of Heat Waves In East Tennessee: Measurements Using Various Heat Wave Definitions

Adesoba, Taiwo Peter, Li, Ying, Silver, Kenneth 04 April 2018 (has links)
Introduction: More frequent and intensive heat waves have been generally considered as a consequence of global climate change. In spite of the fact that there is a lack of generally accepted definition of heat waves in terms of intensity and duration, the adverse impacts of heat wave are undeniable. East Tennessee has experienced noticeably higher summer temperatures in the recent past, including possible deadly heat waves. This study aims at measuring the frequency and duration of heat waves in East Tennessee over the last ten years using various heat definitions extracted from epidemiological literature. Methods: A literature search was conducted in PubMed using key words: Heat wave, mortality and morbidity. The search located 311 peer-reviewed articles that were screened and 108 were reviewed for heat wave definitions. The definitions used in the 108 articles were then summarized and seven most commonly used definitions were selected for this study. Daily temperature (mean, maximum and minimum) data from three weather stations namely Tri-City Airport, Kingsport and Elizabethton in East Tennessee were collected for the period from 2008 to 2017 to test the seven different definitions of heat waves. The World Meteorological Organization (WMO)’s definition “daily maximum temperature for more than five consecutive days exceeding the average maximum temperature (for the 30-year normals period) by at least 9º Fahrenheit (5º Celsius)” was also tested and compared with the seven definitions extracted from epidemiological literature. Results: Using the WMO definition and temperature data from the Tri-City Airport Weather Station located in Bristol, TN, it was estimated that the total number of heat wave in the 10-year period was 58, which spanned a total of 1343 days, or 134.3 days per year on average. The results further indicate that the onset of heat wave days has been earlier within the past four years than the previous years with the earliest occurrence on February 24, 2017. Year 2016 is regarded as the hottest year in the period as virtually the whole of 2016 summer was a heat wave period. It is also worthy of note that the end-date of the heat wave episodes using the WMO definition is observed to have extended for the first time to the month of November as seen in 2016, which was not so for the other years. The heat wave episodes observed with the 97th percentile mean and 90th percentile minimum temperatures in Tri-City Airport Weather Station were lower than the WMO definition. Similar results were observed in Kingsport weather station. But in Elizabethton weather station, the 97th percentile mean and 90th percentile minimum temperatures produced higher episodes of heat waves but shorter days than the WMO definition. Conclusion: Heat wave is deadly and evidences suggest that its manifestation may become severe as more damages are being done to the atmosphere through pollution and deforestation. A reversal of this trend through early warning systems and preparedness is very important and urgent. Further research will look into the mortality health outcome associated with heat waves in this region.
230

Program pro výpočet rozložení optické intenzity / Program for calculation of optical intensity distribution

Golubev, Martin January 2014 (has links)
This diploma thesis deals with system for visible light communication (VLC). There are described basic optical elements like a electroluminescence diode and photodiode. In next chapter is described design of transmitter, optical channel and receiver. Attention is also devoted to modulation suitable for optical communication. The last chapter is devoted to program in Matlab language, which's name is Program for calculation of optical intensity distribution. That program was created in this diploma theses.

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