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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.
81

Molecular developmental analysis of artificial selection response in the male sex combs of Drosophila melanogaster

Cheng, Sheng 14 January 2015 (has links)
<p>Evolutionary innovations, at the molecular level, represent the novel establishment of regulation networks among previously unconnected genes. Understanding the cellular and molecular mechanisms that underlies the development of such innovations is of central importance in evolutionary-developmental research (evo-devo). The sex comb of <em>Drosophila</em> is an excellent model to study the molecular basis of evolutionary innovations. Highline and Lowline are two artificial selected <em>D. melanogaster</em> lines differing in the number of sex comb bristles. It was expected that the “cross-regulation loop” between two transcription factors, <em>Doublesex</em> male isoform (DSX<sup>M</sup>) and <em>Sexcombs reduced</em> (SCR), evolves rapidly and promotes the morphological evolution of sex combs. We used immunofluorescent technique (antibody staining) to compare the expression of DSX<sup>M</sup> and SCR in the forelegs of three different lines (Highline, Wildtype and Lowline). We hypothesized that artificial selection will increase expression of DSX<sup>M </sup>and SCR in the Highline and reduce expression in the Lowline. The fluorescent pictures of antibody staining experiments indicate that the expression region of DSX<sup>M</sup> in the Highline is significantly higher than the expression region in the Lowline, and the expression levels of SCR has minor difference among the three lines. DSX<sup>M</sup> expression is altered by the artificial selection, but SCR expression is not. The influence of artificial selection appears to have been constrained by development. Our investigation provides an approach to test the validity of the models of cross-regulation s between SCR and DSX<sup>M</sup> during development.</p> / Master of Science (MSc)
82

Fuel Selection in Genetically Selected Endurance Running Rats at Submaximal Exercise Intensities

Murphy, Kristina 04 1900 (has links)
<p> Exercise intensity is one of the major factors determining the utilization of carbohydrates (CHO) and lipids in mammalian skeletal muscle. Using indirect calorimetry, we determined maximal oxygen uptake (VO2max) and whole-body rates of CHO and lipid oxidation in rats selectively bred for high and low running capacity (HCR's and LCR's) during exercise at 50, 60, 70 and 80%VO2max. Previous studies have revealed a pattern of selection where mammals with different aerobic capacities use the same proportions of lipids and CHO when exercising at the same relative exercise intensity and as intensity increases, CHO use increases and lipid use decreases. The present results showed that the HCR's had a VO2max and distance run to exhaustion that was 1.3 and 4.0 times greater than the LCR's respectively. Also, both groups of rats followed the pattern of fuel selection seen in previous studies where the same proportions (in%) of lipids and CHO are used at the same relative exercise intensity. On an absolute scale, the HCR's used more lipids and CHO than the LCR's at all exercise intensities but the results were not always statistically significant. We also determined the exercise intensity that elicited the greatest lipid use to be 60% VO2max in both groups.</p> <p> In order to explain these patterns of fuel selection, metabolic indicators, metabolites and enzymes, in skeletal muscle were measured at rest and post exercise for one hour at 60%VO2max. Specifically, ATP and phosphocreatine (PCr) metabolite concentrations were determined in the medial and lateral gastrocnemius, extensor digitorum longus (EDL), tibialis anterior (TA), and soleus muscle. The medial gastrocnemius and soleus were analyzed (pre and post exercise samples were combined) for their oxidative and glycolytic enzyme activity by measuring citrate synthase (CS), cytochrome oxidase (COX), β-hydroxyacyl CoA dehydrogenase (HOAD), and lactate dehydrogenase (LDH) . PCr and ATP concentrations did not change pre and post exercise and between the HCR's and LCR's except for the EDL where there was a significant decrease (P<0.05) in both metabolites after exercise in both groups of rats. For the enzyme measurements, CS and COX activities were higher (P<0.05) in the HCR's for the soleus and HOAD activities were also higher in the HCR's medial gastrocnemius compared to the LCR's. We concluded that the HCR's have a greater oxidative capacity as shown by their greater aerobic and endurance capacity (VO2max and distance to exhaustion), their ability to oxidize a greater absolute amount of lipids and CHO's at the same relative exercise intensity, and their higher activities of oxidative enzymes in the soleus (CS and COX) and medial gastrocnemius (HOAD). Future research into the mechanisms involved in explaining these patterns of fuel selection may include examining fatty acid transport proteins, fatty acid and CHO availability, fiber types, and catecholamines.</p> / Thesis / Master of Science (MSc)
83

Spatial Analysis of Selected Reproductive Health Outcomes of Women Living in the Vicinity of the Sydney Tar Ponds, Sydney, NS

Deluca, Patrick 11 1900 (has links)
Decades of steel production and coking in the community of Sydney, Nova Scotia, have led to severe environmental insult. Increased amounts of air pollution from Sydney Steel Corporation and toxic emissions from the Muggah Creek Watershed have been well documented in several studies of the area since the 1960s. This research examines the potential impacts of exposure to hazardous waste on the reproductive health of women living in Cape Breton Regional Municipality through the following objectives: i) to assess the spatial pattern of various types of adverse reproductive events, plausibly linked to the environmental exposure of interest; ii) to determine if this pattern is related to proximity to the Tar Ponds/Coke Ovens site. To address the first objective, point pattern analysis was applied to observations from the Atlee Perinatal Database to determine if the observed pattern exhibited any clustering. To address the second objective, a multinomial logistic regression model was employed to determine if proximity to the Tar Ponds/Coke Ovens site was an important covariate of the adverse outcomes under study (preterm births, low birthweights, congenital anomalies and stillbirths). The results of the bivariate K-function indicated that there was weak global clustering for preterm births for two different time periods, while the ratio kernel estimates demonstrated that the patterns of the outcomes were non-random even after correcting for the underlying population distribution. The results of the multinomial logistic model demonstrated that variables pertaining to maternal characteristics, pregnancy history, current pregnancy maternal diagnoses, neonatal measures were important explanatory variables in the analysis. Place of residence was an important explanatory variable for preterm births and congenital anomalies. However, due to various limitations these results must be interpreted with caution. / Thesis / Master of Arts (MA)
84

Effects of Age and Thermal Acclimation on the Selected Temperature and Thermal Resistance of Culcid and Simuliid Larvae (Diptera)

Thomas, Anthony 05 1900 (has links)
Black-fly larvae, and mosquito larvae and pupae, are shown to select certain temperature ranges when given a choice in a linear gradient. Larval age has little effect on the temperature selected, but pupae are tolerant of higher temperatures than larvae. The significance of this observation is discussed. The temperature selected is affected by the previous thermal history of the insect, although acclimation to the ambient temperature may be rapid. The final selected temperature of fourth-instar Aedes aegypti larvae was determined. Rearing temperature has a profound effect on the thermal resistance of Aedes aegypti exposed to high temperatures. / Thesis / Master of Science (MS)
85

Novel Preprocessing and Normalization Methods for Analysis of GC/LC-MS Data

Nezami Ranjbar, Mohammad Rasoul 02 June 2015 (has links)
We introduce new methods for preprocessing and normalization of data acquired by gas/liquid chromatography coupled with mass spectrometry (GC/LC-MS). Normalization is desired prior to subsequent statistical analysis to adjust variabilities in ion intensities that are not caused by biological differences. There are different sources of experimental bias including variabilities in sample collection, sample storage, poor experimental design, noise, etc. Also, instrument variability in experiments involving a large number of runs leads to a significant drift in intensity measurements. We propose new normalization methods based on bootstrapping, Gaussian process regression, non-negative matrix factorization (NMF), and Bayesian hierarchical models. These methods model the bias by borrowing information across runs and features. Another novel aspect is utilizing scan-level data to improve the accuracy of quantification. We evaluated the performance of our method using simulated and experimental data. In comparison with several existing methods, the proposed methods yielded significant improvement. Gas chromatography coupled with mass spectrometry (GC-MS) is one of the technologies widely used for qualitative and quantitative analysis of small molecules. In particular, GC coupled to single quadrupole MS can be utilized for targeted analysis by selected ion monitoring (SIM). However, to our knowledge, there are no software tools specifically designed for analysis of GS-SIM-MS data. We introduce SIMAT, a new R package for quantitative analysis of the levels of targeted analytes. SIMAT provides guidance in choosing fragments for a list of targets. This is accomplished through an optimization algorithm that has the capability to select the most appropriate fragments from overlapping peaks based on a pre-specified library of background analytes. The tool also allows visualization of the total ion chromatogram (TIC) of runs and extracted ion chromatogram (EIC) of analytes of interest. Moreover, retention index (RI) calibration can be performed and raw GC-SIM-MS data can be imported in netCDF or NIST mass spectral library (MSL) formats. We evaluated the performance of SIMAT using several experimental data sets. Our results demonstrate that SIMAT performs better than AMDIS and MetaboliteDetector in terms of finding the correct targets in the acquired GC-SIM-MS data and estimating their relative levels. / Ph. D.
86

Towards cold state-selected ion-molecule reactions

Deb, Nabanita January 2014 (has links)
In recent years there has been much progress in the field of cold and ultracold molecular physics and a variety of experimental techniques for producing cold matter now exist. In particular, the generation of trapped molecular ions at mK temperatures has been achieved by sympathetic-cooling with laser-cooled atomic ions. By implementing schemes to selectively prepare and control the internal quantum state of molecular ions, and developing detection techniques, it will be increasingly possible to study cold state-selected chemical collisions in an ion-trap. Most molecular species produced in a selected rovibrational state have a lifetime of a few seconds, before the population is redistributed across numerous rovibrational states by interaction with the ambient blackbody radiation (BBR). Consequently, the investigation of state-selected reaction dynamics at low temperatures in experiments where long time scales (minutes to hours) are required, is hindered. This thesis looks into developing strategies that maintain state selection in molecular ions, allowing one to observe state-selected reactions in cold environments, in particular the state-selected reaction between C<sub>2</sub>H<sup>+</sup><sub>2</sub> and ND<sub>3</sub>. Examining reactive ion molecule collisions under cold conditions provides insight into fundamental reaction dynamics, which are thermally averaged out at higher temperatures. A theoretical model is used to investigate laser-driven, blackbody-mediated, rotational cooling schemes for several <sup>1</sup>&Sigma; and <sup>2</sup>Π diatomic species. The rotational cooling is particularly effective for DCl<sup>+</sup> and HCl<sup>+</sup>, for which 92&percnt; and >99&percnt; (respectively) of the population can be driven into the rovibrational ground state. For the other systems a broadband optical pumping source is found to enhance the population that can be accumulated in the rovibrational ground state by up to 29&percnt; more than that achieved when exciting a single transition. The influence of the rotational constant, dipole moments and electronic state of the diatomics on the achievable rotational cooling is also studied. This approach is extended to consider the BBR interaction and rotational cooling of a linear polyatomic ion, C<sub>2</sub>H<sup>+</sup><sub>2</sub>, which has a <sup>2</sup>&Pi; electronic ground state. The (1-0) band of the &nu;<sub>5</sub> cis-bending mode is infrared active and strongly overlaps the 300 K blackbody spectrum. Hence the lifetimes of state-selected rotational levels are found to be short compared to the typical timescale of ion trapping experiments. Laser cooling schemes are proposed that could be experimentally viable, which involves simultaneous pumping of a set of closely spaced Q-branch transitions on the <sup>2</sup>&Delta;<sub>5/2</sub>-<sup>2</sup>&Pi;<sub>3/2</sub> band together with two <sup>2</sup>&Sigma;<sup>+</sup>– <sup>2</sup>&Pi;<sub>1/2</sub> lines. It is shown that this should lead to >70&percnt; of total population in the lowest rotational level at 300 K and over 99&percnt; at 77 K. In order to identify states of the acetylene ion that could be trapped sufficiently long enough for state-selected reactions in the ion trap with decelerated ND3, the theoretical work has been complemented by experimental investigations into the production of C<sub>2</sub>H<sup>+</sup><sub>2</sub> in selected states, and ion trapping of the same using sinusoidal and digital trapping voltages. Appropriate (2+1) REMPI (Resonance Enhanced Multiphoton Ionization) schemes are used to produce C<sub>2</sub>H<sup>+</sup><sub>2</sub> in different quantum states, with (1+1) Resonance Enhanced Multiphoton Dissociation (REMPD) employed to detect the ion thus produced. The concept of digital ion trapping for ejection onto MCPs is introduced. A comprehensive comparison between sinusoidal and digital trapping fields has been performed with respect to trap depth and stability regions. Programs have been developed to calculate the stability regions for different ions under varying experimental conditions. The trap depth has been derived for both digital and sinusoidal trapping fields. It is observed that as &tau; increases, the trap depth of a digital trap increases. For &tau; = 0.293, the trap depth and stability diagram for both sinusoidal and digital trapping fields would be equivalent. The trap depth at which the sinusoidal trap operates experimentally in our research group is ~1.36 eV. In contrast, the experimental parameters at which the digital trap operates generates a trap depth of 1.21 eV. Ca<sup>+</sup> Coulomb crystals have been formed, stably trapped and stored for extended periods of time in both sinusoidally and digitally time-varying trapping fields. The sympathetic cooling of a diverse range of ions into Ca<sup>+</sup> Coulomb crystals is demonstrated, again using both sinusoidal and digital trapping fields. Mass spectrometric detection of ionic reaction products using a novel ejection scheme has been developed, where ejection is achieved by switching off the trapping voltage and converting the quadrupole trap into an extractor-repeller pair by providing the ion trap electrodes with appropriate ejection pulses. This technique is developed using a digital trapping voltage rather than the sinusoidal trapping voltage, as ejection with sinusoidal trapping voltages is not clean (resonance circuitry used in the electronics induces ringing after switching off the trapping voltage). Coulomb crystals, both pure Ca<sup>+</sup> and multi-component crystals, are ejected from the ion trap and the TOF trace obtained is recorded on an oscilloscope. When the integrated, base-line subtracted TOF peak is plotted against the number of ions in a Ca+ crystal and sympathetically-cooled Ca<sup>+</sup> – CaF<sup>+</sup> crystal, a linear relationship is obtained. This technique is found to be well mass-resolved, with the signal arising from CaOH<sup>+</sup> (57 amu) and CaOD<sup>+</sup> (58 amu) resolvable on the TOF trace. This technique would enable one to monitor a reaction in a Coulomb crystal where the reactant and product species are both either lighter or heavier than calcium, such as the reaction between C<sub>2</sub>H<sup>+</sup><sub>2</sub> and ND<sub>3</sub>, something which has not been previously possible. It is, also, potentially a very important technique for reactions with many product channels.
87

A Comparative Study of Children's Intensity of Task-Involvement in a Selected Nursery School

Roan, Bi-Sho 08 1900 (has links)
The problem of this study was a comparison of young children's intensity of task—involvement in child—selected activities. A group of 23 children, four to six years of age, was selected as the subjects from a university affiliated child development laboratory school. These children were observed during child-selected activities for five consecutive weeks. The instrument utilized to collect the data was the Intensity Of Involvement Scale, composed of seven categories of intensity from "Unoccupied" to "Complete." To obtain reliable data, two observers were involved in the observation and a carefully planned procedure of observation was followed accurately. The comparison of children's intensity of task-involvement among child-selected activities, using statistical methods of mean and standard deviation, yielded a similar result among various groups of children. The learning centers in which children were involved most intensely were water play, family living, manipulative, and art centers. The children, however, were involved in the reading, block, and writing centers less intensely. In comparing children's intensity of task-involvement between age-groups and sex-groups, the analyses of two-way t-test revealed that age-differences were significant (p<.05) but sex-differences were not significant in children's overall intensity of task-involvement. Also, the results showed that the significance of differences in children's intensity of task-involvement in each child-selected activity depended more upon the age than the sex of children. In addition, individual differences in children's intensity of task-involvement were examined using mean, frequency distribution, and range. The finding was that children differed from one another in their degrees and variability of intensity of task-involvement in child-selected activities.
88

Erosão e/ou neutralização da flexão de gênero na língua hebraica israelense: relações morfossintáticas entre numerais cardinais e/ou pronomes com substantivos e configurações verbais do futuro em textos selecionados a partir do século XXI / Erosion and / or neutralization of gender bending in Israeli Hebrew: morphosyntactic relations between cardinal numbers and/or pronouns with nouns and future verbal settings on selected texts of the starding of the XXI century

Silva, Candido Sousa da 21 November 2016 (has links)
A presente tese de doutoramento insere-se no debate sobre a temática da erosão e/ou neutralização da marca de gênero da Língua Hebraica Israelense nas relações morfossintáticas entre numerais cardinais e/ou pronomes com substantivos e configurações verbais do futuro em textos selecionados a partir do século XXI. O trabalho está fundado na percepção, derivada da literatura especializada sobre o tema, de que existe uma tendência da perda da marca de gênero nestas relações morfossintáticas estabelecidas, além de outras nuances como o apagamento do gênero feminino nas 2ª e 3ª pessoas plurais do sistema verbal no tempo futuro. Em termos de estratégias de pesquisa, a investigação fundamenta-se no estudo da formação e consolidação da identidade israelense e suas implicações equalizadoras no plano linguístico quanto ao uso da flexão de gênero tornando-os como unidade empírica. Nosso objetivo é examinar o funcionamento deste fenômeno linguístico, como isso é expresso na escrita e quais suas implicações na fala. A hipótese de trabalho para esta pesquisa é que o fenômeno de erosão e/ou neutralização da marca de gênero no Hebraico tem causado profundas transformações na estrutura da língua que se caracteriza na distinção clara de dois gêneros, seja nos nomes e numerais ou, ainda, no sistema verbal. Neste quadro, pretendo validar ou refutar conceitos tradicionais utilizados no estudo do Hebraico, tomando como base a medida da variação diglóssica. Por fim, desejamos, através dos dados obtidos nas obras selecionadas, apresentar nossas reflexões e apontar possíveis motivações para uma tendência erosão e/ou neutralização das configurações pesquisadas. / This doctoral thesis is part of the debate on the issue of erosion and / or neutralization of gender brand of Israeli Hebrew Language in morphosyntactic relationship between cardinal numbers and / or pronouns with noun and verb of the future settings on selected texts from the XXI century. The work is based on the perception, derived from the specialized literature on the subject, that there is a trend of the lost gender brand in these morphosyntactic relationships established, beyond other nuances like erasing female gender in 2nd and 3rd plural people of the verbal system in the future tense. In terms of research strategies, the investigation is based on the study of the formation and consolidation of Israeli Identity and their equalizing implications the linguistic plan in the use of gender bending making them as empirical unit. Our objetive is to examine the functioning of this linguistic phenomenon, as it is expressed in writing and what its implications in speech. The working hypothesis for this research is that the erosion phenomenon and / or neutralization of the gender brand in Hebrew has caused profound changes in the structure of language that characterized the clear distinction between two genres, whether the names and numerals, or more the verbal system. In this presentment, I intent to validate or refute traditional concepts used in the study of Hebrew, based on the measurement of diglossic variation. Finally, we wish through the data in the selected works, present our ideas and to point possible motivations for an erosion trend and / or neutralization of the surveyed settings.
89

Estudo do envolvimento dos loci reguladores da reação inflamatória aguda na determinação da sensibilidade ou resistência ao choque endotóxico induzido por lipopolissacarídeo. / Study of the involvement of acute inflammatory reaction loci in the determination of sensitivity or resistance to endotoxic shock induzed by LPS.

Borrego, Andrea 19 May 2009 (has links)
Linhagens de camundongos selecionadas para a máxima (AIRmax) ou mínima (AIRmin) resposta inflamatória aguda diferem tanto na susceptibilidade a infecção por Salmonella entérica sorotipo Typhimurium (S. Typhimurium) e ao LPS. Diferentes frequências dos alelos do gene Nramp1, envolvido na resistência inata a infecção por S. Typhimurium, foram encontradas nas linhagens AIRmax e AIRmin. Para o estudo da interação do gene Nramp1 com os loci da inflamação, sublinhagens homozigotas para os alelos R e S deste gene foram produzidas, AIRmaxRR, AIRmaxSS, AIRminRR e AIRminSS. Os animais AIRmaxRR foram sensíveis ao LPS, enquanto que os AIRminSS foram os mais resistentes a endotoxina. Quando desafiados com LPS, os animais AIRmaxRR apresentaram maior nível sérico de citocinas inflamatórias e maior expressão gênica de Tnf, Il6 e Il1b em células de fígado e medula óssea. Os AIRminRR expressaram e produziram maiores níveis de Il10. Através da análise da expressão gênica global em células de medula óssea, os AIRminSS mostraram um número maior de genes envolvidos na resposta ao LPS. / Lines of mice genetically selected for maximal (AIRmax) and minimal (AIRmin) acute inflammatory reaction differ in susceptibility to infection with Salmonella enterica serotype Typhimurium (S. Typhimurium) and to LPS sensitivity. Different frequencies of Nramp1 alleles, involved in innate resistance to S. Typhimurium infection, were found in AIRmax and AIRmin mouse lines. To study the Nramp1 gene interaction with acute inflammatory QTL, AIRmaxRR, AIRmaxSS, AIRminRR and AIRminSS sublines were produced. AIRmaxRR were found to be extremely sensitive to LPS, while the AIRminSS were the most resistant line to endotoxin. After LPS challenged, AIRmaxRR animals showed higher levels of inflammatory cytokine sera and as well as Tnf, Il6 and IL1b gene expression intensities in liver and bone marrow cells. Il10 expression was higher in AIRminRR mice. The global gene expression analysis in bone marrow cells after LPS stimulus showed higher number of differently expressed genes in AIRminSS mice.
90

Efeitos de um progama de treinamento de caminhada livre e caminhada nórdica em idosos sedentários / Effects of a Nordic walking and free walking training program on static and dynamic balance parameters, self-selected walking speed, locomotor rehabilitation index and quality of life of sedentary elderly : a randomized controlled trial

Gomeñuka, Natalia Andrea January 2016 (has links)
Introdução: Considerando o rápido aumento da população de idosos e da sua expectativa de vida, junto com a expansão das intervenções de caminhada nórdica (NW) como método de treinamento para idosos, há uma necessidade de estudos de base experimental (ensaios clínicos randomizados controlados, ECRs) de caráter preventivo e de boa qualidade metodológica que permitam aos profissionais da educação física, da saúde e da reabilitação a tomada de decisões relativas ao tipo, volume, intensidade de exercício da NW na promoção da saúde dos idosos sedentários. Objetivos: o presente estudo teve como objetivos (estudo A) determinar, por meio de revisão sistemática de ensaios clínicos randomizados, se o treinamento sistematizado com NW, comparado à caminhada livre (CL), produz efeitos benéficos sobre componentes da aptidão funcional de idosos sedentários saudáveis, também avaliar (estudo B) os efeitos de oito semanas de treinamento de NW e CL na qualidade de vida (QV), no equilíbrio estático, na variabilidade dinâmica, na velocidade autosselecionada de caminhada (VAS) em esteira e no índice de reabilitação locomotor (IRL) de idosos sedentários, e também avaliar (estudo C) os efeitos de oito semanas de treinamento de NW e CL no trabalho mecânico (externo- Wext, trabalho mecânico interno- Wint, no trabalho mecânico total – Wtot), no mecanismo pendular (R), no Custo de transporte (C), na frequência cardíaca de exercício (FCexercício), na sensação subjetiva de esforço (RPE), e nos parâmetros eletromiográficos (amplitude média do sinal e co-contração) dos músculos: deltoides anterior (DA), tríceps braquial (TB), vasto lateral (VL), bíceps femoral (BF), tibial anterior (TA) e gastrocnêmio medial (GM) de idosos sedentários. Desenho Experimental: ECR. Local da Pesquisa: Escola de Educação Física, Fisioterapia e Dança (ESEFID) da Universidade Federal do Rio Grande do Sul Porto Alegre, Rio Grande do Sul, Brasil. Métodos: Participaram deste estudo 32 idosos sedentários randomizados em dois grupos (grupo NW), n=16, idade: 64,6±4,1 anos, massa: 81,5±10,7kg e estatura: 166,3±7,5cm; e o grupo CL, n=16, idade: 68,6±3,9 anos, massa: 74,6±14,5kg e estatura: 161,6±10,3cm), realizaram treinamento de NW e CL durante 8 semanas. Desfechos do estudo A: foram avaliadaos com um estudo de revisão sistemática parâmetros da aptidão funcional de idosos (força e resistência dos membros superiores, força e resistência dos membros inferiores, mobilidade, flexibilidade dos músculos da coluna lombar e da região posterior da coxa, amplitude geral da articulação do ombro, resistência aeróbia e velocidade autosselecionada). Desfechos do estudo B: foram avaliados utilizando questionário de qualidade de vida, testes de equilibrio em plataforma de força e coleta cinemática 3D durante caminhada em esteira rolante para determinação dos Parâmetros funcionais (qualidade de vida, equilíbrio estático e dinâmico, velocidade autosselecionada de caminhada e índice de reabilitação locomotor). Desfechos do estudo C: foram avaliados através coletas de dados espirométricos, cinemáticos 3D e eletromiográficos da caminhada em esteira rolante em diferentes velocidades os parâmetros mecânicos e do mecanismo pendular (trabalho mecânico externo, interno e total- Wext, Wint, Wtot, Recovery -R, Custo de transporte -C, Velocidade autosselecionada -VAS), parâmetros eletromiográficos (amplitude média do sinal e co-contração dos músculos DA, TB, VL, BF, TA e GM), frequência cardíaca de exercício – FCexercício, e sensação subjetiva de esforço - RPE, de idosos sedentários,. 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 (NW e CL) e os momentos (pré e pós treino). 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 Science (SPSS) v.22.0. Adotou-se um nível de significância de α=0,05. Conclusão: os treinamentos de NW e de CL, promovem melhoras nos componentes da aptidão funcional; no equilíbrio estático e na variabilidade dinâmica de idosos. Contudo algumas diferenças entre as duas intervenções se relacionam ao princípio da especificidade do treinamento e ocorrem apenas nos componentes que receberam mais estímulos impostos pela técnica da caminhada com bastões, especialmente nos membros superiores. Ainda, o incremento da VAS na esteira aliada à utilização do IRL, nos permitem concluir que o treinamento de NW tem relevância clínica e é recomendado como meio de melhora do condicionamento físico e como método de reabilitação de idosos sedentários. Esta atividade física proporciona adaptações centrais com melhora significativa na mobilidade funcional de idosos. Deste modo, após treinamento de resistência aeróbica com e sem bastões os idosos aumentam a velocidade de locomoção nas atividades diárias e com menor custo metabólico devido às adaptações centrais e melhora do mecanismo pendular devido à maior proximidade da VAS à velocidade ótima de caminhada. Ainda há adaptações importantes na ativação muscular decorrentes do treinamento de NW em idosos indicando uma redução dos níveis de co-contração de membros superiores na caminhada sem bastões, à qual repercute diretamente na melhora da aptidão física, na independência funcional dos idosos. Além disso, recomendamos à NW como uma atividade física segura e efetiva para esta população quando a periodização do treinamento são realizados com o volume e intensidade estritamente controlados. / Introduction: Considering the rapid increase in the elderly population and their life expectancy, together with the expansion of Nordic walking (NW) interventions as a training method for the elderly, there is a need for experimental studies (randomized controlled trials, ECRs) of preventive character and of good methodological quality that allow the professionals of physical education, health and rehabilitation to make decisions regarding the type, volume and intensity of NW exercise in the health promotion of sedentary elderly. Objectives: This study aimed (study A) to determine, through a systematic review of randomized clinical trials, whether systematic training with NW, compared to free walking (FW), has beneficial effects on components of the functional capacity of sedentary elderly, also (study B) avaluate the effects of eight weeks of NW and FW training on quality of life (QoL), static balance, dynamic variability, self-selected walking speed on treadmill (SSWS) and Locomotor rehabilitation index (LRI) of sedentary elderly, and also evaluate (study C) the effects of eight weeks of NW and FW training on mechanical work (external, internal and total mechanical work -Wext,Wint, Wtot), pendular mechanism (R), Cost of (C), exercise heart rate (HRexercise), rate of perceived exertion (RPE), and electromyographic parameters (mean signal amplitude and co-contraction) of muscles: Anterior Deltoid (AD), Triceps Brachii (TB), Vastus Lateralis (VL), Femoral Biceps (BF), Anterior Tibialis (TA) and Medial Gastrocnemius (MG) of sedentary elderly. Experimental Design: Controlled Clinical Trial (ECR). Research Location: School of Physical Education, Physiotherapy and Dance (ESEFID), Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil. Methods: The sample comprised 33 sedentary participants randomly divided into two groups (NW group, n =16, age: 64.6 ± 4.1 years old, weight: 81.5 ± 10.7 kg and height: 166.3 ± 7.5 cm; and FW group, n =16, age: 68.6 ± 3.9 years, mass: 74.6 ± 14.5 kg and height: 161.6 ± 10.3 cm), performed NW and FW training for 8 weeks. Outcomes of Study A: Parameters of functional fitness of the elderly (upper limb strength and endurance, lower limb strength and endurance, mobility, lumbar spine and posterior hip muscle flexibility, general amplitude of the shoulder joint, aerobic endurance and self-selected speed). Outcomes of study B: Functional parameters (QoL, static and dynamic balance, SSWS and LRI).Outcomes of Study C: Mechanical parameters and pendular mechanism (Wext, Wint, Wtot, R, C, SSS), electromyographic parameters (mean signal amplitude and Co-contraction of AD, TB, VL, BF, AT and MG muscles), HRexercise RPE of sedentary elderly. Statistics Analysis: Sample description data, at baseline, were compared by applying one-way ANOVA. The outcomes were analyzed using Generalized Estimates (GEE), to compare the groups (NW and CL) and the moments (pre and post training). A Bonferroni post-hoc was used to identify the differences between effects and interactions. The data were presented in model-based adjusted means, and were analyzed with the software Statistical Package for the Social Science (SPSS) v.22.0. A significance level of α = 0.05 was adopted. Conclusion: NW and FW training, promotes improvements in functional fitness components; in the static balance and in the dynamic variability of the elderly. However, some differences between the two interventions are related to the principle of training specificity and occur only in the components that received the most stimuli imposed by the walking technique with poles, especially in the upper limbs. Furthermore, the increase in SSWS on the treadmill combined with the use of LRI allows us to conclude that NW training has clinical relevance and is recommended as a means of improving physical conditioning and as a method of rehabilitation of sedentary elderly. This physical activity provides central adaptations with significant improvement in the functional mobility of the elderly. Thus, after aerobic resistance training with and without poles, the elderly increase the speed of locomotion in daily activities and with lower metabolic cost due to the central adaptations and improvement of the pendulum mechanism due to the greater proximity of the SSWS to the optimal speed of walking. There are still important adaptations in muscle activation resulting from NW training in the elderly indicating a reduction in the levels of co-contraction of upper limbs in walking without walking poles, which directly affects the improvement of physical fitness and functional independence of the elderly. In addition, we recommend NW as a safe and effective physical activity for this population when the periodization of training is performed with the volume and intensity strictly controlled.

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