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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.
61

Investigation of the microbial diversity and functionality of soil in fragmented South African grasslands along an urbanization gradient / Jacobus Petrus Jansen van Rensburg

Van Rensburg, Jacobus Petrus Jansen January 2010 (has links)
The diversity of microorganisms and the influence of their enzymatic activities in soil are critical to the maintenance of good soil health. Changes in these parameters may be the earliest predictors of soil quality changes, potentially indicating anthropogenic influences. The goal of this study was to investigate the soil microbial diversity and function of grasslands along an urbanization gradient. Soil samples were collected in the Potchefstroom municipal area, South Africa, at specific sites. Sampling sites were described as urban, suburban and rural - according to the V-I-S (Vegetation-Impervious surface-Soil) model of Ridd (1995). Soil samples were collected over a warmer, wet season (May) and a colder, dry season (August) over two years (2007 and 2008). Collected soil samples were characterised using certain physical and chemical parameters. Plant species composition and abundance were determined at each site, along with basic site data (soil compaction, percentage ground cover, percentage bare ground, percentage organic material present). The Shannon-Weaver diversity index was used to calculate biodiversity values for all the investigated sites regarding collected plant species composition. The microbial component of the soil was quantified and characterized using culture-dependent and culture-independent techniques. Culture-dependent techniques included the investigation of the aerobic heterotrophic bacteria and fungi. Organisms were plated out on different media, and the bacterial component was broadly grouped using morphology. Dominant organisms were identified by sequencing of PCR amplified 16S ribosomal DNA fragments. Shannon-Weaver index for bacterial diversity was determined for each of the sites. Denaturing gradient gel electrophoresis (DGGE) profiling of selected bacterial communities were also conducted. Microbial community function was determined using enzyme assays of five major groups of enzymes, namely (i) dehydrogenase; (ii) β-glucosidase; (iii) acid phosphatase, (iv) alkaline phosphatase and (v) urease. Plant species results were then brought into context with microbiological diversity and functionality results using multivariate statistics. Physical and chemical parameters of the collected soil samples revealed patterns present along the urbanization gradient. The pH values were mostly higher in the sub-urban and urban sites than in the rural sites. Electrical conductivity values were generally highest in the sub-urban sites. Plant species composition revealed trends along the urbanization gradient. Ordinations clearly grouped the plant species into rural, sub-urban and urban groups regarding plant species composition. Rural sites had the highest number of plant species. Shannon-Weaver values regarding the plant diversity supported the plant species composition data indicating higher plant diversity in the rural areas, followed by the sub-urban and the urban areas. Plant structural data indicated that forbs were most numerous in the rural sites, and less so in the urban sites. Higher average aerobic heterotrophic bacterial levels were present in the urban soil samples. The bacterial levels were lower in the sub-urban and rural soil samples. Subsequent identification of the dominant bacteria in the soil samples revealed organisms of the genus Bacillus dominated the aerobic heterotrophic bacterial communities in the soil samples. Bacillus species dominated the soil samples along the urbanization gradient. Shannon-Weaver indices based on culture-dependent methods indicated that urban sites had the highest biodiversity. These results could have been exaggerated, because of an overestimation of the number of bacterial morphotypes present in samples. Fungal levels were higher in the soil from samples collected at the rural samples sites. The culture-independent method (DGGE) was not optimized and inconclusive results were obtained. Enzyme assays revealed that potential dehydrogenase, β-glucosidase and urease activity followed a trend along the urbanization gradient, with urban samples registering the highest values and rural sites the lowest. Enzymes involved in carbohydrate catabolism (β-glucosidase and dehydrogenase) registered significantly higher potential activity in urban sites than the sub-urban and rural sites. The results could indicate that urban sites have the potential to lose carbon at higher rates than the rural sites. This aspect may need further investigation. Higher potential urease activity could indicate higher N-cycling in the urban soil environment. Ordination results for soil-, plant- and microbial diversity as well as microbial functionality indicated certain trends along the urbanization gradient. Plant species composition and structure data indicated that urbanization has a definite effect on the plant communities in the urban ecosystem. Results regarding aerobic heterotrophic bacteria populations and potential enzyme activity of the dehydrogenase, β-glucosidase (both active in the carbon cycle) and urease (active in the nitrogen cycle) illustrated clear trends along the urbanization gradient. In conclusion, results indicated that urbanization has an effect on plant species composition, and the population and function of aerobic heterotrophic bacteria and the fungal population. Furthermore, this study demonstrated the potential of using microbial diversity and activity as tools to investigate carbon utilization and storage along an urban-rural gradient. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2011
62

The contribution of the project management office to project delivery in the consulting engineering industry / Jean van der Merwe

Van der Merwe, Jean January 2013 (has links)
Effective project management (PM) is increasingly required for strategy implementation, business transformation management, continual improvement and pioneering product development and service provision. The systematic approach of PM (based on best practices and experience) aims to improve the chances of project success in a competitive environment where scarce resources (capital, human, opportunity, time, etc.) needs to be utilized most effectively. The contribution a project management office (PMO) can make in the medium sized consulting engineering industry to deliver more successful projects was investigated. The investigation involved determining the current state of both PM and PMO maturity in medium sized consulting engineering organisations in South Africa. Furthermore, the required maturity, or level of development, of PM and PMOs were also determined using the prediction orientated Delphi survey method. In the literature study, the concepts of PM, PMO and their maturity determination, successful project delivery, background to the consulting engineering industry in South Africa and similar PM and PMO maturity studies were investigated. From the literature study, an existing maturity survey was selected for each of the concepts PM and PMO. These existing and tested maturity surveys were combined into a single survey. Some demographic information deemed applicable from the literature study was also included in the survey and distributed in a multi-round survey to medium sized organisations similar to the author's organisation, operating in the mining and energy sectors mainly. The current PM and PMO maturity of the organisations taking part in the survey were determined in round 1 of the survey. The required PM and PMO maturity were determined from the round 2 survey results that were completed after the respondents were provided with the round 1 survey statistically averaged maturity levels in an effort to reach a form of consensus amongst the respondents. The round 1 survey was distributed to 161 respondents (response rate of 53%). Round 2 was distributed to the 86 respondents that completed round 1 (response rate of 55%). From the survey results and literature study it was found that there is a definite increase in PM and PMO maturity required in order for medium sized consulting engineering organisations to deliver more successful projects in the mining and energy sector. It was also seen that the maturity levels required for both PM and PMO are not the maximum maturity levels possible. From the empirical study, a definite relationship between PMO and PM was confirmed and it was seen that generally an organisation with a PMO tends to have higher PM maturity levels. For a PMO to be successful, from literature it was seen that the PMO needs to adapt to the organisation and environment it functions in. It was also discovered that a PMO is successful if it reaches the goals it set for itself. The PMO also contributes by systematically and continuously improving and adapting the PM of the company to add the most value to both internal and external customers of the PMO. It is the researcher's opinion that the study is not representative of all medium sized consulting engineering organisations in SA and further research is required to determine industry specific PM and PMO maturity levels and to determine the resulting contribution a PMO can make in this regard. / MBA, North-West University, Potchefstroom Campus, 2014
63

The functionality grid as paradigm for management of technology

Lochner, Frederick Christoffel 12 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2011. / Technology is a critical component in modern society. Management of Technology (MOT) should be a major focus of management studies. At present the status of MOT is much less than it should be. Part of the reason is that there is little consensus about the body of knowledge for MOT. This can be traced down to as far as an inadequate consensus about the very nature of technology itself. There is a need for a simple and elegant conceptual foundation. There is a need for an accepted paradigm to govern MOT. The paradigm discourse initiated by Thomas Kuhn allows for a comprehensive frame of reference about theory contestation and about the attributes required from a contesting theory to achieve the ultimate status of a paradigm. In order to help create a coherent and streamlined conceptual foundation for MOT, this research evaluates the functionality grid as a paradigm. To realise this goal, this study first assesses the functionality grid’s compliance with the theoretical requirements of a paradigm, and secondly its compliance with the empirical requirements of a paradigm. The theoretical test uses a newly created format, the paradigm template, to establish the necessary criteria. The functionality grid is then subjected to a critical review using the said criteria. It is found that it meets the requirements of a valid paradigm. For measurement of empirical requirements, Kuhn’s own criteria are used. This second part of the study involves three practical exercises to examine the practical descriptive power of the functionality grid, and its ability to help first with the formation of a technology attuned mindset of participants, second with the improvement in technological knowledge and third with an increase in the technological literacy of participants. The outcomes of these tests are positive as well. The dissertation concludes that the functionality grid would be a viable paradigm to serve as a guide for the further development of MOT. The functionality grid becomes confirmed as a paradigm for MOT, because it contains all the attributes to serve as a coherent and streamlined conceptual structure for this discipline. Given this outcome, it is recommended that more effort be invested to understand, promote and popularise the functionality grid; and the various analytical frameworks derived from it. It is recommended that it becomes an explicit part of the book of knowledge for MOT and that it constitutes the basis for an educational curriculum to be shared by every MOT professional and student.
64

Microtransactions : A Study of Consumer Behavior and Virtual Goods/Services Among Students at Linköping University in Sweden

Artz, Brian, Kitcheos, Alex January 2016 (has links)
Within the realm of applications, a relatively new payment form has emerged: called Microtransactions. These small one-time payments (less than 10 Euros) offer an addendum to an existing app, service, or game. Microtransactions have generated a revenue stream largely due to the tech savvy segment of young adults aged 18 to 24, but there hasn’t been significant research from an academic perspective which sheds light on this trend. This issue prompted the research question: Which quantifiable elements of a Microtransaction contribute to a university student’s purchase decision? The phenomenon of Microtransactions has not previously been studied under traditional theories of consumer behavior, which is what the scope of this research provided. The consumer behavior theories selected include: Ego Depletion Theory, Extended Self, and Perceived Value Theory. The selected methodology was a quantitative survey and content analysis. The data collected partially supported Perceived Value Theory, but was unable to validate Ego Depletion and Extended Self as significant influences on purchasing behaviors of Microtransactions among university students. Although the theories were unable to support all our hypotheses, we still concluded with two major findings. First, pricing and functionality are the primary elements of a Microtransaction which university students will consider before purchasing. Second, the Perceived Value Theory’s consumption values of Emotion and Finance are, indeed, consumption values shared among university students.
65

"L'eau c'est la vie": Seeking Sustainable Water Access and Community Participation in Rural Cameroon

Beal, Eva January 2016 (has links)
In the rural water scheme projects across sub-Saharan Africa, the participatory Community Based Management model has become the norm. Through initial financing by oustide funders, the goal is for communities to independently take on the financing of the operation and maintenance (O&M) of the improved water schemes, thereby ensuring sustainability and functionality of the pumps. Evidence has been gathering, however that this model, combining ideals of collective action with the logics of commodification, has been frequently failing, one in three hand pumps in Africa are out of function, and communities struggle to meet the financing needs of O&M in infrastructures which perpetuate isolation. This, however, does not lie fully in the fault of the communities, or implementation, but also in theoretical downfalls of the CBM. Looking at a community-based rural project in the Tikar region of Central Cameroon as well, this research reveals the limits of CBM to achieving sustainable water access, as well as reveal new angles and paradigms to pursue.
66

Qualidade de vida de pacientes submetidos à ressecção de tumores musculoesqueléticos. / Quality of life of patients undergoing resection of musculoskeletal tumors.

Prieto, Gisele Brides 08 April 2013 (has links)
Este estudo avalia a qualidade de vida de sujeitos acometidos por tumores musculoesqueléticos de membros inferiores, submetidos a cirurgias de ressecção, com salvamento de membro ou amputação. A casuística foi composta por 56 sujeitos, avaliados no período de 14 meses (agosto de 2011 a setembro de 2012), que foram divididos em três grupos: 1- 12 amputados; 2- 16 em pós-operatório de salvamento do membro (colocação de endoprótese ou reconstrução biológica); 3- sujeitos saudáveis (sem diagnóstico de câncer), selecionados entre a população em geral, de forma pareada com os outros grupos, segundo sexo, idade, escolaridade e condição socioeconômica. Além do Critério de Classificação Econômica Brasil (2010), foram aplicados dois protocolos de avaliação, um de qualidade de vida (Medical Outcomes Study 36 - Item Short-Form Health Survey - SF-36) e o outro de capacidade funcional (Toronto Extremity Salvage Score - TESS), ambos adaptados culturalmente e validados no Brasil. Os dados foram estatisticamente analisados, conforme preconizado por cada protocolo. Os resultados indicaram que ambos os tipos de abordagem cirúrgica (amputação ou reconstrução) produziram prejuízos na capacidade funcional e na qualidade de vida dos sujeitos acometidos por tumores musculoesqueléticos, quando comparados à população saudável. Diferentemente do que apontaram outros trabalhos internacionais com casuística semelhante, os sujeitos submetidos a amputações apresentaram resultados melhores relacionados à sua capacidade funcional e à qualidade de vida, na maioria dos domínios do SF36 e com relevância estatística (p=0,001) no escore final do TESS, do que aqueles submetidos a técnicas de salvamento de membro. Por fim, é importante analisar a percepção dos sujeitos sobre sua funcionalidade e qualidade de vida, de modo a encontrar caminhos mais adequados no processo de reabilitação desta população. / This study appraises the quality of life of individuals with musculoskeletal tumors in lower extremities, undergoing resection surgeries with extremity salvage or amputation. The casuistry was composed by 56 subjects assessed in the course of 14 months (from August, 2001 to September, 2012), who were divided into 3 groups: 1- 12 amputated; 2- 16 in postsurgical extremity salvage (endoprosthesis implant or biological reconstruction); 3- healthy subjects (without cancer diagnosis), selected from the whole population, paired off with other groups, according to sex, age, schooling and socioeconomic status. Besides the Critério de Classificação Econômica Brasil (2010), two assessment protocols were applied, one about quality of life (Medical Outcomes Study 36 - Item Short-Form Health Survey - SF-36), and the other one about functional capacity (Toronto Extremity Salvage Score - TESS), both culturally adapted and validated in Brazil. The data were statistically analyzed according to what each protocol proclaims. The results revealed that both surgical approach types (amputation or reconstruction) caused harm to the functional capacity and to the quality of life of the subjects suffering from musculoskeletal tumors, when compared to the healthy population. Unlike what other international papers with similar casuistry have shown, the subjects undergoing amputation presented better results related to their functional capacity and quality of life, in the majority of the domains of SF36, with statistical relevance (p=0.001), than those submitted to the techniques of extremity salvage. Finally, it is important to analyze the subjects\' perception on their functionality and quality of life in order to discover the most suitable ways in the process of rehabilitating this population.
67

Cinesioterapia no controle postural de idosos : metanálise, ensaio clínico e validação de instrumento de avaliação isocinética

Meereis, Estele Caroline Welter January 2017 (has links)
O controle postural é a base do sistema de controle motor humano, produzindo estabilidade e condições para o movimento. Com o processo de envelhecimento acontecem mudanças que ocasionam um declínio na capacidade de produção de força e de manutenção do equilíbrio, diminuindo a capacidade funcional e aumentando o risco de quedas em idosos. Diante da perspectiva de que o exercício pode minimizar esse processo, o objetivo da presente tese é verificar a influência de treinamentos com ênfase no fortalecimento muscular e treino de equilíbrio em variáveis que influenciam o controle postural, sendo estas a força muscular, o equilíbrio postural, funcionalidade e risco de quedas em idosos. Para isso, foram desenvolvidos três estudos, sendo uma metanálise para demonstrar os estudos e lacunas existentes sobre o assunto, um estudo de validação e um ensaio clínico randomizado, os quais serão apresentados nos capítulos I, II e III, respectivamente. No capítulo I, a metanálise buscou verificar a influência de intervenção com treinamento de força e do treino com multicomponentes na funcionalidade e risco de quedas em idosos, avaliados pelos testes Timed Up and Go (TUG), Sit to Stand (STS) e/ou Escala de Equilíbrio de Berg (EEB). Desse modo, foram realizadas buscas nas bases de dados Pubmed, Web of Science, PEDro, Cochrane e Lilacs. Foram encontrados 1434 estudos, dos quais 32 preencheram os critérios de elegibilidade e foram incluídos. Os resultados apontaram para a melhora em todos os desfechos investigados quando realizados treino multicomponentes em comparação com grupos controle. Já o treino de força, em comparação com grupos controles, mostrou benefício apenas para o desfecho STS realizado em 30 segundos. Poucos estudos compararam treino de força com treino multicomponentes, e aqueles que compararam não encontraram diferença entre os dois. Diante disso, foi verificado que, para determinar qual tipo de treino é mais benéfico sobre os parâmetros funcionais, é necessária a realização de novos ensaios clínicos. Esses achados motivaram a execução do estudo clínico apresentado no capítulo III. No entanto, para avaliação da força com um novo instrumento proposto para avaliação do torque isocinético de joelho foi necessário realizar o estudo de validação e confiabilidade, descrito no capítulo II o qual foi realizado com 20 indivíduos do sexo feminino que realizaram avaliações com equipamento considerado padrão ouro para verificar a validade e repetidas avaliações com o referido equipamento para verificar a confiabilidade intradia e interdias. A análise estatística foi realizada utilizando coeficiente de correlação intraclasse (CCI), intervalo de confiança de 95% (IC95%), erro padrão da medida (EPM), gráficos de Bland-Altman e nível de significância de 5%. Nos resultados relacionados à concordância entre os dois equipamentos, foram verificadas excelentes correlações entre os dados tanto para extensores quanto para flexores de joelho (CCI 0,96 e 0,94, respectivamente) e na análise de Bland-Altman, os dados encontraram-se distribuídos dentro dos limites de concordância entres os dois equipamentos. Na análise intradia e interdias, os EPMs do equipamento para avaliação isocinética de joelho variaram entre 4,9% e 11,3%. A acurácia da avaliação, verificada na comparação do torque experimentar e o torque analítico obtido com pesos conhecidos foi de 99,9%. Diante disso, verifica-se que o equipamento proposto demostrou ser um equipamento válido e confiável, sendo uma alternativa simples e de baixo custo possível de quantificar o pico de torque de indivíduos não atletas do sexo feminino. O capítulo III descreve o ensaio clínico realizado com 18 idosas, divididas randomicamente para grupo controle (GC: 71.5 ± 3.02 anos), grupo intervenção com ênfase no treinamento de força (GF: 67.3 ± 3.01 anos) e no treinamento de equilíbrio (GE: 71.8 ± 5.38 anos). A intervenção foi realizada em grupo durante 60 minutos, duas vezes por semana, durante 8 semanas. Constou de exercícios de aquecimento, treino de força e alongamento para o GF e aquecimento, treino de equilíbrio e alongamento para o GE. O GC foi orientado a manter as atividades habituais. Para a comparação entre os momentos e entre os grupos foi utilizada uma ANOVA two-way com Post hoc de Bonferroni. O nível de significância utilizado para todos os testes foi de 5%. Nos resultados foram encontradas diferenças significativas entre a avaliação pré e pós intervenção relacionas ao equilíbrio postural na situação de olhos abertos para o COPvel (p= 0,01) e área da elipse de 95% do COP (p= 0,04) e ao TUG (p= 0,04) para os idosos do GE, demostrando que o treinamento com ênfase no equilíbrio melhorou variáveis relacionadas ao equilíbrio e a funcionalidade. Além disso, foi verificado diferença significativa entre grupos GC e GF relacionada ao pico de torque de flexores de joelho na comparação pós-intervenção (p= 0,04) demostrando que o GF apresentava maior força. Diante do presente estudo, foi observado que os dois programas apresentaram benefícios em comparação ao GC, que não realizou intervenção. No entanto, foi observado que a especificidade do treino influenciou na melhora das variáveis, sugerindo que as intervenções realizadas com idosos sejam compostas de exercícios tanto de força como de equilíbrio. / Postural control is the basis of the human motor control system, producing stability and conditions for movement. During the aging process, changes occur declining the ability to produce strength and maintain balance, reducing functional capacity and increasing the risk of falls. Considering that physical exercises can minimize this process, the objective of this study is to verify the influence of kinesiotherapy with emphasis on strength and balance training in postural balance, muscle strength, functionality and risk of falls in the elderly. For this, three studies were developed, consisting of a meta-analysis of the existing studies and its gaps about the subject, a validation study and a randomized clinical trial, which will be presented in Chapters I, II and III, respectively. In Chapter I, the meta-analysis sought to verify the influence of intervention with strength training and multicomponent training on the functionality and risk of falls in the elderly, evaluated by the timed up and go (TUG), sit to stand (STS) and/or Berga Balance Scale (BBS) tests. The databases searched were Pubmed, Web of Science, PEDro, Cochrane and Lilacs. Of the 1434 studies found in the literature, 32 met the eligibility criteria and were included. The results pointed to an improvement in all of the outcomes investigated when comparing multicomponent training groups to control groups. Strength training, compared to control groups, showed benefit only for the 30STS outcome. Few studies compared multicomponent training with strength training, and those which made this comparison did not find a difference between the two trainings. It was observed that new clinical trials are required in order to determine which type of training is most beneficial on functional parameters. These findings motivated the execution of the clinical study presented in chapter III. However, in order to evaluate the force using a new instrument for knee isokinetic torque evaluation, it was necessary to perform the validation and reliability study of this equipment, described in Chapter II, in which 20 female subjects performed evaluations with the new equipment and with an equipment considered “gold standard”. In addition, 20 women performed repeated evaluations in the new equipment in order to verify the intraday and interdays reliability. Statistical analysis was performed using intraclass correlation coefficient (ICC), 95% confidence interval (95%CI), standard error SEM, Bland-Altman charts and significance level of 5%. The results pointed out to an excellent correlation between the data for both extensors and flexors (ICC= 0.96 and 0.94, respectively). In the Bland-Altman analysis, the data were distributed within the limits of agreement between the two equipments. In the intraday and interdays analysis, the SEMs of the knee isokinetic evaluation equipment varied between 4.9% and 11.3%. The accuracy of the evaluation, verified in the comparison of the experimental torque and the analytical torque obtained with known weights was 99.9%. Therefore, it was verified that the proposed equipment proved to be valid and reliable, being a simple and low-cost alternative to quantify the peak torque of female non-athletes, inferring that it can also be used for to individuals with similar torque/force, as non-athletes of both sexes in the age group from 60 years. Chapter III describes, clinical trials performed with 18 elderly women, randomly assigned into 3 groups: 6 in the control group (CG: 71.5 ± 3.02 years), 6 in the intervention group with emphasis on strength training (SG: 67.3 ± 3.01 years) and 6 in the Intervention group with emphasis on balance training (BG: 71.8 ± 5.38 years). The intervention was performed for each exercise group during 60 minutes, twice a week, for 8 weeks, consisting of warm-up exercises, SG stretching and stretching exercises, and warm-up, balance training and stretching for BG. The CG maintained the usual activities. A two-way ANOVA for repeated measurements was used for the comparison between the moments and between the groups, with Bonferroni Post hoc to identify the differences. The level of significance set for all tests was 5%. The results demonstrated significant differences between the pre-and post-intervention evaluations related to the postural balance in the open-eyes situation for COPvel (p = 0.01) and the ellipse area of 95% of COP (p = 0.04) and TUG (p = 0.04) for the elderly of the BG, showing that the training with an emphasis on balance improved variables related to balance and functionality. A significant difference between GC and SG groups was verified related to the maximum torque of knee flexors in the post-intervention comparison (p = 0.04), demonstrating that SG presented greater strength. In view of the present study, it was observed that both programs presented benefits in comparison to the CG, whose participants did not follow any kind of intervention. However, it was observed that the specificity of the training had an influence on the improvement of the variables, suggesting that the interventions performed with the elderly are composed of both strength and balance exercises.
68

Efeitos do treinamento da caminhada nórdica e da caminhada livre sobre parâmetros clínico-funcionais e biomecânicos de pessoas com doença de parkinson : ensaino clínico randomizado

Monteiro, Elren Passos January 2014 (has links)
Introdução: Alterações de parâmetros clinico-funcionais e parâmetros biomecânicos da marcha, são características marcantes na Doença de Parkinson (DP). Tais alterações são incapacitantes para a realização das atividades de vida diária (AVDS), pois representam um alto risco de quedas e comprometem a qualidade de vida (QV) desta população. Embora o exercício físico seja preconizado com um modelo de intervenção terapêutica eficaz para minimizar os sintomas da doença, pouco se sabe sobre os efeitos da caminhada nórdica sobre sintomas motores e não motores em pacientes com DP. Objetivo: o objetivo do presente estudo foi avaliar e comparar os efeitos de um programa de treinamento de caminhada nórdica e de caminhada livre sobre parâmetros clínico-funcionais e biomecânicos da marcha de pessoas com DP. Desenho Experimental: ensaio clínico controlado randomizado (ECR). Local da Pesquisa: Escola de Educação Física da Universidade Federal do Rio Grande do Sul e Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brasil. Métodos: Participaram deste estudo 33 voluntários, com idade acima de 50 anos, de ambos os sexos, com diagnóstico clínico de DP idiopática, com o estadiamento entre 1 a 4 na escala Hoehn e Yahr (H&Y). Voluntários com DP receberam dois tipos de intervenções: treinamento de caminhada nórdica (CN, N = 16) e caminhada livre (CL, N = 17), durante seis semanas. Com o intuito de avaliar os efeitos do treinamento, avaliações foram realizadas: Baseline: avaliação inicial pré-treinamento + préfamiliarização (T1); avaliação pós-familiarização + pré-treinamento (T2); avaliação pós-treinamento (T3). Desfechos do estudo A: Sintomas motores: estadiamento e gravidade da DP, equilíbrio (EEB), mobilidade funcional da caminhada, velocidade autosselecionada da caminhada (VAS), e índice de reabilitação (IR). Sintomas não motores: função cognitiva, sintomas depressivos e qualidade de vida. Desfechos do estudo B: Parâmetros cinemáticos (espaço-temporais e estabilidade dinâmica da caminhada) e parâmetros neuromusculares (amplitude do sinal eletromiográfico, limiar inicial e final de ativação, duração de ativação e índice de co-contração dos músculos: vasto lateral (VL), bíceps femural (BF), tibial anterior (TA) e gastrocnêmio medial (GM)). Análise Estatística: Os dados de descrição da amostra, no baseline, foram comparados aplicando-se ANOVA one-way. Os desfechos foram analisados utilizando as Equações de Estimativas Generalizadas (GEE), para a comparação entre os grupos (CN e CL) e os momentos (T1, T2 e T3). Utilizou-se um post-hoc de Bonferroni, para identificar as diferenças entre os efeitos e interações. Os dados foram apresentados em “model-based adjusted means”, e foram analisados com o software Statistical Package for the Social Sciense (SPSS) v.20.0. Adotou-se um nível de significância de α=0,05. Resultados: A intervenção proposta no presente estudo proporcionou um efeito benéfico significativo após o período de treinamento, para todos os domínios da CIF (função e estrutura corporal, atividade e relações sociais e ambientais). No estudo A, para os desfechos dos sintomas motores, houve uma redução da UPDRS III (p < 0,001), aumento nos escores da EEB (p < 0,035), incremento da mobilidade funcional da caminhada por meio da redução do TUGVAS (p < 0,001), TUGVR (p < 0,001), VAS (p < 0,001) e IR (p < 0,001), bem como para os desfechos dos sintomas não motores: aumento na função cognitiva (p < 0,046), redução dos sintomas depressivos (p < 0,001), e aumento para os domínios de QV geral (p < 0,001), físico (p < 0,037), psicológico (p < 0,019), participação social (p < 0,007) e intimidade (p < 0,033), independente do grupo de treinamento. O grupo da CN apresentou melhora, estatisticamente significativa, no domínio autonomia (p < 0,001), quando comparado ao grupo da CL. No estudo B, para os desfechos cinemáticos, houve uma redução do tempo de contato tempo de contato (TC), tempo de balanço (TB), comprimento (CP) e frequência de passada (FP) para a CN quando comparada a CL (p < 0,05). Em relação aos parâmetros neuromusculares, houve um aumento na amplitude do sinal EMG do VL e BF, redução do limiar final de ativação (offset) do VL e GM (p < 0,05), redução da ativação do VL e BF (p< 0,05) e índice de co-contração do TA e GM (p < 0,05), enquanto que o grupo da CL apresentou melhoras significativas somente na amplitude do GM quando comparado ao grupo da CN. Conclusão: Conclui-se que os programas de treinamento de CN e CL, promoveram melhora sem diferença entre os grupos, em todos os domínios da funcionalidade propostos pela CIF (estrutura e função corporal, atividade e relação social, e meio ambiente), após a intervenção proposta. Entretanto, o uso de bastões através da técnica da CN em comparação ao treinamento de caminhada sem bastões (CL), mostrou vantagens na mobilidade funcional e parâmetros neuromusculares pontuais (índice de co-contração de membros inferiores, offset dos músculos TA e GM) ao mesmo tempo em que melhorou aspectos clínico-funcionais, fundamentais para a saúde e QV dos indivíduos com DP. / Introduction: Changes in clinical, functional and biomechanical parameters of gait are remarkable features in Parkinson's disease (PD). Such changes are disabling for the performance of daily living activities (DLAs) as they represent a high risk of falls and impair quality of life (QL) in this population. Although exercise is recommended as an effective model of therapeutic intervention, to minimize the symptoms of this disease, little is known about the effects of Nordic walking on motor and non-motor symptoms in patients with PD. Purpose: The aim of this study was to evaluate and compare the effects of a Nordic and free walking training program on clinical, functional and biomechanical parameters of gait, in people with PD. Experimental Design: Randomized controlled clinical trial (RCT). Study Site: Physical Education School of the Federal University of Rio Grande do Sul and the Clinical Hospital of Porto Alegre, in Porto Alegre, Rio Grande do Sul, Brazil. Methods: The sample comprised 33 participants, aged above 50 years, of both sexes, with a clinical diagnosis of idiopathic PD, with the staging of 1-4 in the Hoehn and Yahr scale (H&Y). The participants received two types of intervention: Nordic walking training program (NW, n = 16) and free walking training program (FW, n = 17), during six weeks. Aiming to evaluate the effects of the training program, the participants underwent the tests in the following period: pre-training + prefamiliarization (T1); post-familiarization + pre-training (T2); post-training (T3). Outcomes of Study A: Motor symptoms: Staging and severity of PD, balance, walking functional mobility, self selected walking velocity, and rehabilitation index. Non-Motor symptoms: Cognitive function, depressive symptoms and QL. Outcomes of Study B: Kinematic parameters (spatiotemporal and dynamic stability of walking) and neuromuscular parameters (amplitude of the EMG signal, initial and final activation threshold, activation time and co-contraction index, of the following muscles: Vastus Lateralis (VL), Biceps Femoris (BF), Tibialis Anterior (TA), Gastrocnemius Medialis (GM). Statistical Analysis: Sample characteristics, at baseline, were compared by applying the One Way ANOVA. Outcomes were analyzed using the Generalized Estimates Equations (GEE), to compare groups (NW and FW) and moments (T1, T2 and T3). The Bonferroni post-hoc was used to identify differences between effects and interactions. Data were presented in a “model-based adjusted means”, and analyzed using the Statistical Package for Social Sciences (SPSS, v.20.0) software. A significance level of α=0.05, was adopted. Results: The intervention proposed in this study provided a significant beneficial effect after the training period, for all ICF domains (body function and structure, activity, and social and environmental relations). Regarding study A, for motor symptoms outcomes, there was a reduction in UPDRS III (p < 0,001), increase in EEB scores (p < 0,035), increase in walking functional mobility through TUGVAS reduction (p < 0,001), as well as TUGVR (p < 0,001), VAS (p < 0,001) e IR (p < 0,001) reduction. For non-motor symptoms outcomes, there was an increase in cognitive function (p < 0,046), reduction of the depressive symptoms (p < 0,001), and increase in the overall QL domain (p < 0,001), as well as in the physical (p < 0,037), psychological (p < 0,019), social participation (p < 0,007) and intimacy (p < 0,033) domains, independent of the training group. The NW group showed significant improvement in the autonomy domain (p < 0,001), when compared to the FW group. Regarding study B, for kinematic outcomes, there was a reduction in contact time (CT), swing time (ST), stride length (SL) and stride frequency (FP), for NW when compared to FN (p <0.05 ). Regarding the neuromuscular parameters, an increase in the amplitude of the VL and BF EMG signal, reduction of the final activation threshold (offset) of the VL and GM (p <0.05), reduction in the activation of the VL and BF (p <0.05) and reduction in the co-contraction index of the TA and GM (p <0.05), were found for the NW group, whereas the FW group showed statistically significant improvements only on the amplitude of GM when compared to the CN group. Conclusion: The NW and FW training programs provided improvement, without difference between groups, in all functionality domains proposed by ICF (body function and structure, activity and social relationships, and environment), after the intervention. However, the use of sticks in the technique of NW compared to the free walking without the sticks (FW training), showed advantages in functional mobility and neuromuscular specific parameters (index of co-contraction of lower limbs, offset of muscles TA and GM), improving, as well, clinical and functional aspects, that are imperative to health and QL of individuals with PD.
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Efeito do treinamento de força e suplementação de proteínas nas adaptações musculares e funcionais em idosos fragilizados: comparação entre sexos / Effect of strength training and protein supplementation on muscular and functional adaptations in frail elderly: comparison between sexes

Jambassi Filho, José Claudio 28 August 2018 (has links)
Um programa de treinamento de força (TF) associado à suplementação de proteínas tem sido proposto uma estratégia para promover adaptações musculares e funcionais em idosos fragilizados. Todavia, ainda não está bem estabelecido se a magnitude dessas adaptações é influenciada pelo sexo. Assim, o objetivo do presente estudo foi comparar a eficácia do TF associado à suplementação de proteínas nas adaptações musculares e funcionais entre homens e mulheres fragilizados. Noventa idosos pré-frágeis e frágeis com idade >= 65 anos foram estratificados por sexo (? e ?) e aleatorizados em treinamento de força associado à suplementação de proteínas (PTN) ou placebo (PLA). Os participantes realizaram 16 semanas de TF progressivo (duas sessões por semana) associado a duas doses diárias de 15 g de suplementação de PTN ou PLA, ingeridos após o café da manhã e jantar. A composição corporal (absortometria radiológica de dupla energia), área de secção transversa muscular (ultrassom), força muscular dinâmica (uma repetição máxima) e isométrica (dinamômetro isocinético), atividade elétrica dos músculos (eletromiografia), mobilidade funcional (timed up-and-go), resistência muscular de membros inferiores (timed-stands), estabilidade postural e risco de quedas com diferentes instabilidades (Biodex Balance System) foram avaliados pré e pós-intervenção. A massa muscular total, braços, pernas, apendicular e área de secção transversa muscular do reto femoral demonstraram aumentos significantes após a intervenção em homens e mulheres (p < 0,05), sem diferenças entre os grupos. No entanto, a gordura corporal, massa muscular do tronco e área de secção transversa muscular do vasto lateral não demonstraram alterações significantes após 16 semanas de intervenção (p > 0,05). Todos os grupos apresentaram aumentos nos valores de uma repetição máxima nos exercícios leg-press e supino, pico de torque e taxa de desenvolvimento de torque após a intervenção (p < 0,05), sem diferenças entre os sexos. A resistência muscular dos membros inferiores, estabilidade postural e o risco de quedas em instabilidade alta demonstraram aumentos significativos pós-intervenção (p < 0,05), sem diferenças entre homens e mulheres. Os resultados pós-intervenção não mostraram diferenças significativas entre homens e mulheres na qualidade de vida (p > 0,05). Nenhuma diferença foi observada entre homens e mulheres na ingestão de proteínas (p > 0,05). Os achados sugerem que programa de treinamento de força associado à suplementação de proteínas não promove respostas distintas entre homens e mulheres idosos pré-frágeis e frágeis / Strength training program associated with protein supplementation has been proposed as a strategy to promote muscular and functional adaptations in frail elderly. However, it is not yet well established whether the magnitude of these adaptations is influenced by sex. Thus, the aim of the presente study was to compare the efficacy of resistance training associated with protein supplementation in the muscular and functional adaptations between frailty men and women. Ninety pre-frail and frail elderly >= 65 years old were stratified by sex (? and ?) and randomized to either strength training associated with protein supplementation (PTN) group or placebo (PLA) group. The participants performed 16 weeks of progressive strength training (two sessions per week) associated with two daily doses of 15 g of PTN or PLA supplementation, ingested after breakfast and dinner. The body composition (dual X-ray absorptiometry), muscle cross-sectional area (ultrasound), dynamic muscle strength (one maximal repetition) and isometric (isokinetic dynamometer), electrical muscle activity (electromyography), functional mobility (timed up-and -go), resistance of the lower limbs (timed-stands), postural stability and risk of falls with different instabilities (Biodex Balance System) were assessed pre- and post-intervention. The total muscle mass, arms, legs, appendicular and rectus femoris muscle cross-sectional area showed significant increases after intervention in men and women (p > 0.05), with no differences between groups. However, body fat, muscle mass of the trunk, and vastus lateralis muscle cross-sectional area did not show significant changes after 16 weeks of intervention (p > 0.05). All groups presented increases in the values of one maximum repetition in leg-press and supine exercises, peak torque and rate of torque development after the intervention (p < 0.05), with no differences between the sexes. The muscular resistance of the lower limbs, postural stability and risk of falls in high instability showed significantly increases post-intervention (p < 0.05), with no differences between men and women. Post-intervention results showed no significant differences between men and women in quality of life (p > 0.05). No difference was observed between men and women in protein intake (p > 0.05). The findings suggest that the strength training program associated with protein supplementation does not promote distinct responses among pre-frail and frail elderly men and women
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Caracterização do efeito da crotoxina sobre a funcionalidade dos neutrófilos da medula óssea / Characterization of the effect of crotoxin on the functionaly of bone marrow neutrophils

Lima, Tatiane Soares de 10 August 2015 (has links)
Estudos anteriores demonstraram que a crotoxina (CTX), o principal componente do veneno de Crotalus durissus terrifucus, apresenta ação anti-inflamatória, inibindo a migração celular e a atividade fagocítica de neutrófilos peritoneais. Esses efeitos inibitórios são prolongados, uma vez que podem ser observados até 14 dias após a administração de uma única dose dessa toxina. Considerando-se a vida média curta dos neutrófilos, é difícil explicar como a ação inibitória da CTX sobre os neutrófilos circulantes e peritoneais persiste por períodos prolongados após a administração de uma única dose da toxina. Dessa forma, o objetivo desse estudo foi avaliar o efeito in vitro e in vivo da CTX sobre a atividade funcional dos neutrófilos da medula óssea de camundongos e alguns dos mecanismos moleculares envolvidos na ação inibitória da CTX sobre as funções avaliadas. Para os ensaios in vitro, os neutrófilos foram incubados com a CTX (0,08 &mu;g/mL), por 1 ou 24 horas. Para os ensaios in vivo, os animais foram pré-tratados com uma única administração de CTX (44 mg/kg), 1 dia antes do isolamento das células. Uma vez obtidos os neutrófilos, os seguintes parâmetros funcionais foram avaliados: quimiotaxia, adesão à fibronectina, fagocitose, produção de espécies reativas do oxigênio e desgranulação. Os resultados obtidos demonstraram que a CTX, in vitro e in vivo, inibiu os processos de quimiotaxia, adesão à fibronectina e fagocitose de partículas opsonizadas, entretanto não alterou a produção de espécies reativas do oxigênio ou a desgranulação em neutrófilos da medula óssea. Esses resultados demonstram que a CTX induz efeito inibitório sobre a funcionalidade dos neutrófilos da medula óssea, particularmente sobre funções associadas à polimerização de actina e consequente reorganização do citoesqueleto. Ainda, com o objetivo de elucidar os possíveis mecanismos envolvidos neste efeito inibitório, foram realizados ensaios para a análise da expressão do receptor CR3, bem como para a avaliação da expressão total e da atividade de proteínas de sinalização intracelular envolvidas na polimerização de actina nos neutrófilos. Os resultados obtidos mostraram que a CTX inibiu a expressão de ambas as subunidades (CD11b e CD18) do receptor CR3, bem como inibiu a atividade de Syk, Vav1, Cdc42, Rac1 e RhoA e a expressão da subunidade 1B do complexo Arp2/3. Em conjunto, os resultados desse estudo mostraram que a CTX inibe a funcionalidade dos neutrófilos da medula óssea e que essa ação está associada à inibição do receptor CR3, bem como à inibição da atividade de Syk e de suas proteínas downstream, o que resulta na redução da formação de filamentos de F-actina. Os resultados desse estudo comprovam a hipótese de que ação inibitória prolongada da CTX sobre a atividade dos neutrófilos circulantes e peritoneais está associada a alterações funcionais dos neutrófilos da medula óssea. Ainda, considerando-se a participação central dessas células na resposta inflamatória aguda, esse estudo contribui para a elucidação do efeito anti-inflamatório prolongado da CTX / Previous studies demonstrated that crotoxin (CTX), the main component of Crotalus durissus terrificus venom, presents anti-inflammatory properties, inhibiting cell migration and the phagocytic activity of peritoneal neutrophils. These inhibitory effects are long-lasting, since it can be observed up to 14 days after a single administration of this toxin. Considering the short half-life of neutrophils, it is difficult to explain how the inhibitory effect of CTX on circulating and peritoneal neutrophils persists for long periods after a single injection of this toxin. Thus, the aim of this study was to evaluate the in vitro and in vivo effect of CTX on the functionality of bone marrow neutrophils from mice and some of the molecular mechanisms involved on the inhibitory effect of CTX on these functions. For in vitro assays, neutrophils were incubated with CTX (0,08 &mu;g/mL), for 1 or 24 hours. For in vivo assays, the animals were pretreated with a single administration of CTX (44 mg/kg), 1 day before the isolation of cells. Once obtained the neutrophils, the following functional parameters were evaluated: chemotaxis, adhesion to fibronectin, phagocytosis, reactive oxygen species production and degranulation. The results demonstrated that CTX, in vitro and in vivo, inhibited the processes of chemotaxis, adhesion to fibronection and phagocytosis of opsonized particles, however, it did not alter the reactive oxygen species production and degranulation. These results showed that CTX induces an inhibitory effect on the functionality of bone marrow neutrophils, particularly on functions that depend on actin polymerization and cytoskeleton rearrangement. Furthermore, to elucidate some possible mechanisms involved on this inhibitory effect, assays to analyze the expression of the receptor CR3, as well as, assays to analyze the total expression and activity of signaling proteins involved on actin polymerization were done. The results showed that CTX inhibited both subunits of CR3 (CD11b and CD18) and the activity of Syk, Vav1, Cdc42, Rac1 and RhoA and the expression of the subunit 1B from Arp2/3. Together, the results presented herein demonstrate that CTX inhibits the functionally of bone marrow neutrophils and that this effect is associated to the inhibition of CR3 receptor and inhibition of the activity of Syk and its downstream signaling proteins, which results in the decrease of F-actin. The results prove the hypothesis that the long-lasting inhibitory effect of CTX on the activity of circulating and peritoneal neutrophils is associated to functional modifications of bone marrow neutrophils. Besides, considering the central role of these cells on the inflammatory response, this study contributes to the better understanding of the long-lasting anti-inflammatory effect of CTX

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