139 resultados para Frequência


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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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INTRODUCTION: The autonomic nervous system (ANS) could be investigated in a noninvasive way by the heart rate variability analysis (HRV) which has contributed to several health areas such as physiotherapy. OBJECTIVE: To gather information regarding the use of HRV on physiotherapy aims at providing an update of the findings for the area on journals of national circulation. MATERIALS AND METHODS: The journals of national circulation classified as greater than B2 or B2 and with free access and complete texts in some internet sites were searched on 21 area WebQualis resulting on selection of Revista Brasileira de Fisioterapia, Fisioterapia e Pesquisa and Fisioterapia em Movimento using the keywords: autonomic nervous system, sympathetic nervous system, physiotherapy and heart rate variability. RESULTS: The search resulted in 19 articles being 17 clinical trials and two case reports. CONCLUSION: The HRV has been used as a resource of interventions evaluation, as pathological conditions common to clinical practice investigation and to physiological conditions interpretation in physiotherapy. The HRV is principally used to the cardiorespiratory specialty of physiotherapy.

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The main objective of this study was to analyze the behavior of variables related to swim ability at and above maximal lactate steady state (MLSS), performed at continuous and intermittent conditions in individuals with different aerobic performance levels. Participated of this study male swimmers with ages between 20 to 25 years, specialists in events of 400 m, 800 m and 1500 m and open water swims, with at least 3 years of experience in the modality. The individuals performed a maximal 400-m swim test. After this test, they were divided into two groups, in accordance with the speed attained during 400-m swim test: G1 (higher performance) and G2 (lower performance). For the determination of continuous MLSS (MLSSc), 2 to 4 trials of 30-min were performed. For the determination of the intermittent MLSS (MLSSi) 2 to 4 trials of 30-min (12 repetitions of 2 min 30 s, with 30 s of rest) were performed, in constant speed, with the first trial performed at 102.5% MLSSc. Th technical indexes, stroke rate (FB) and stroke length (CB) were determined in all tests. The SR was calculated trough recordings using the time needed to perform five stroke cycles. The SL was calculated dividing the speed by the SR. There was no significant difference on the antropometric characteristics between groups. The speed at and above MLSSc were significantly higher at G1 (1,23±0,05 e 1,27±0,06, respectively) than G2 (1,10±0,06 e 1,13±0,06, respectively). There was significant change in SL and SR in G2. In the same way, there was significant change in SL and SR only in G2, above MLSSc. Similar to continuous condition, the speeds at and above MLSSi were significantly higher in G1 (1,27±0,05 e 1,30±0,05, respectively) do que no G2 (1,14±0,07 e 1,16±0,07, respectively). There was significant change in SL and SR only in G2. There was significant change in SR and SL in both groups above MLSSi. Thus,...(Complete abstract click electronic access below)

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O estudo do conteúdo de foraminíferos de 8 amostras de sedimentos superficiais coletados em manguezal do norte da Ilha do Cardoso, sul do Estado de São Paulo, no verão (período chuvoso) de 2001, ao longo de um transecto no sentido da Baía de Trapandé para o interior, revelou dois segmentos distintos: a) uma planície inferior lamosa, com menor tempo de exposição sub-aérea e maior diversidade específica, dominada por Ammotiumcassis, A.salsum, Arenoparrella mexicana e Trochamminainflata, com abundância expressiva de Caroniaexilis na parte mais baixa e de Miliammina fusca na parte mais alta; b) uma planície superior arenosa, com maior tempo de exposição sub-aérea e menor diversidade, dominada por M. fusca e com abundância expressiva de T. inflatana parte mais baixa. Os sedimentos investigados são colonizados por foraminíferos exclusivamente aglutinantes, representados por 21 espécies de 16 gêneros. Dados de abundância relativa, riqueza, diversidade e equitatividade das espécies ao longo do transecto são apresentados, bem como os valores de salinidade, pH, oxigênio dissolvido e temperatura, medidos a partir da água intersticial dos sedimentos no momento da coleta das amostras. São feitas comparações com um estudo anterior, similar, que focalizou amostras coletadas, nos mesmos pontos, no inverno (período seco) de 2002. Os resultados obtidos interessam às análises de sistemas estuarinos modernos e antigos, bem como a projetos envolvidos com o diagnóstico do estado de conservação de áreas litorâneas, sendo úteis ao Setor de Petróleo e Gás

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Introdução: A variabilidade da frequência cardíaca (VFC) descreve o comportamento dos intervalos RR que está relacionado às ações do sistema nervoso autônomo (SNA) sobre o nódulo sinusal. Essa pode ser influenciada por diversos fatores dentre eles a obesidade, doença de etiologia multifatorial definida como um acúmulo excessivo de gordura corporal. Objetivo: Avaliar em jovens obesos com idade entre 18 e 23 anos o comportamento autonômico cardíaco, durante o repouso, por meio da análise linear e não linear dos índices da VFC bem como associá-lo a eventos de desconforto músculoesquelético influenciados ou não pela prática regular de exercício físico nessa população. Metodologia: Para a realização deste estudo foram analisados dados de 68 voluntários jovens, de ambos os sexos, distribuídos de forma não randomizada em dois grupos: o G1 constituído por 32 obesos, 20,21 ± 1,66 anos e o G2 por 36 não obesos, 20,8 ± 1,47 anos sendo considerado como critério de classificação dos voluntários o índice de massa corpórea (IMC). O protocolo experimental consistiu da captação da frequência cardíaca batimento a batimento, por meio de uma cinta de captação fixada no tórax do voluntário juntamente com um receptor de frequência cardíaca fixado no punho. Para esta captação o voluntário foi orientado a permanecer em repouso na posição de decúbito dorsal sobre um colchonete, durante 30 minutos, com a respiração espontânea. Além disso, foram aplicados dois questionários, ou seja: versão curta do International Physical Activity Questionaire (IPAQ) - Questionário Internacional de Atividade Física, a fim de classificar o nível de atividade física e o Questionário Nórdico, para detectar eventuais sintomas osteomusculares decorrentes das atividades de vida diária e/ou atividades física. Os índices da VFC analisados foram: análise linear... (Resumo completo, clicar acesso eletrônico abaixo)

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Indivíduos imunocomprometidos possuem maior risco de desenvolver linfomas associados ao EBV. A detecção desse vírus em sangue periférico e a determinação de sua carga viral podem ter importância na evolução clínica de indivíduos portadores do HIV. Foram avaliadas 156 amostras de pacientes HIVpositivos pela reação em cadeia da polimerase em tempo real (qPCR) para detecção e quantificação da carga viral do EBV. 123/156 (78,8%) casos apresentaram carga viral detectável para o EBV, sendo que a carga viral média foi de 6,9x10-3 cópias de EBV/célula. Foi detectada elevada carga viral do EBV em indivíduos com falha terapêutica ou sem HAART (p =0,0076), em coinfectados pelos EBVs 1 e 2 (p=0,0205), em pacientes com altas cargas de HIV (rho=0,27614, p=0,0005) e longos períodos de infecção pelo HIV (rho= 0,24164, p =0,0026) e os que apresentavam altos níveis de linfócitos T CD8 + (rho=0,19286, p =0,0159). A amplificação do gene EBNA-2 para realização da tipagem viral foi possível em 95/123 (77,2%) amostras, das quais 72 (75,8%) revelaram infecção pelo EBV-1, 9 (9,5%) pelo EBV-2 e 14 (14,7%) apresentavam coinfecção entre os EBVs 1 e 2. Esses dados estão de acordo com a literatura visto que o tipo 1 é predominante em países ocidentais e 70,0% da coorte era composta por indivíduos caucasianos e heterossexuais. A maioria dos pacientes que apresentaram coinfecção pelos EBVs 1 e 2 tiveram contagem de linfócitos T CD4 + entre 200 e 499 células/μL de sangue segundo classificação CDC (p =0,0272). Quanto a analise do gene BNLF-1, a amplificação foi possível em 99/123 (80,5%). Desses 50/99 (50,5%) apresentavam a deleção de 30pb no gene, enquanto 49/99 (49,5%) não a possuíam. Em conjunto, os resultados obtidos evidenciam deterioração do sistema imunitário, caracterizada...(Resumo completo, clicar acesso eletrônico abaixo)

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In this work we report the development of a tube amplifier built to be used in magnetic probe diagnostic of plasma. The probe is used to measure the magnetic field in the theta-pinch system presently running in our university. We present the calculations and procedures to determine the configuration of circuits and specify the components of the power supply, the preamp stage and the power stage. The circuit configuration and the characteristics of the components was obtained. A representative model of the system behavior gave the transfer function of the amplifier. Theoretical predictions of frequency response and the feedback effects were compared to the experimental values and showed very good agreement. The amplifier works between a frequency bandwidth of 20 an 30 kHz and supply a maximum power of 12 W

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Introduction: The triangular index and the Poincaré plot (or Lorenz plot) are the best known indexes obtained from geometric methods. The triangular index (TINN, RRtri) represent the global variability of the subject and SD1, which reflects the parasympathetic component, SD2, index of global variability and its relationship (SD1/SD2) are obtained from the Poincaré plot. Despite the literature showing changes in the cardiovascular system during and after the resistance exercise (RE), aspects related to autonomic modulation of heart against these conditions have not been explored yet, so it is important to evaluate this behavior. Objectives: Analyze the acute effects of RE on the cardiac autonomic modulation during recovery (REC) through analysis of geometric indices of heart rate variability (HRV), applied with different intensities and muscle groups in healthy and active young. Methods: Were evaluated 24 young, 22.25 ± 2.4 years and 24.47 ± 3.08 kg/m2, underwent an experimental protocol of five stages, in the first stage was conducted a test of one maximum repetition (1RM) in upper limbs (UL) and lower limb (LL), and the following steps were initiated interventions to 40 (E) and 80% (F) of 1RM. Considered for HRV analysis the periods: baseline and immediately after exercise, both in supine... (Complete abstract click electronic access below)

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The genus Corydoras, the highest among the Siluriformes, Callichthyidae is owned by the family, consisting of 177 valid species and widely distributed in cis-Andean portion of South America How striking feature has two longitudinal series of dermal plates covering almost the entire body. Cytogenetic studies in Callichthyidae show many chromosomal rearrangements, including events of polyploidy in their evolutionary history, particularly the genus Corydoras, in which the variation is the diploid number of 2n = 40 to 2n = 134 chromosomes. The absence of information on the frequency of chromosomes in the group Bs motivated this work with the species Corydoras aeneus. A population from the Tietê River basin in Ribeirão Claro (subbasin Corumbataí - Rio Claro, SP) was sampled a total of 20 subjects (10 males and 10 females) and 30 metaphases per individual were analyzed cytogenetically. Were carried out by impregnation techniques silver (Ag-NOR). The observed modal diploid number was 2n = 60 (26m +26 sm +8 st), with the variable occurrence of 1 or 2 Bs chromosomes in males and a B chromosome in females, both acrocentric. Regarding the variation in the frequency of chromosome Bs, the occurrence of two B chromosomes is directly linked to males, because there were no female sampled with the occurrence of two chromosomes Bs The low frequency of Bs in females suggests that this event can be sporadic this sex, different from males in which this appears to be set supernumerary chromosome showing a higher frequency of 2 Bs than the actual modal number of 2n = 60. Further studies will be performed to understand the dynamics of the B chromosome in the population

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The present work aims to conduct a study of the economic feasibility of the implementation of variable frequency inverters in pump systems with variable flow rates. The concern with the reduction of energy expenditure in industries raised in 2001 due to the energy crisis that hit Brazil at that time, forcing industries to reduce their electric costs under penalty of fines if this were not done (MOREIRA, 2008). Frequency inverter is an electronic device that allow greater control in the operation of pumping systems and also a reduction in electrical consumption, being a viable solution to achieve a reduction in energy consumption. For the development of this work, approaching important topics in pumping systems was necessary in order to make a correct choice of hydraulic pumping and also other components responsible for the operation of the system , such as electric motors and frequency inverters. In the case study, a theoretical analysis of the behavior of electrical consumption in systems with variable flow rates was performed, comparing when the system is operated via frequency inverters and when the system is operated without such a device. As expected, the result of the implantation of the device was quite satisfactory, and the primary goal of reducing energy expenditure was achieved. Also important to highlight the environmental issue of this work, as all forms of energy production affects nature in some way, achieving a reduction in consumption also contributes indirectly in environmental conservation

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Micronuclei (MN) originate from chromosome fragments or whole chromosomes that lag behind at anaphase during cell division can occur due to excessive exposure to harmful agents, defects in mitosis and / or DNA repair process. The study evaluated the frequency of micronuclei in cytological samples after daily use of alcohol -based mouthwash mouth in smokers and non-smokers. We assessed 30 subjects, aged between 17-42 years and established as exclusion criteria: alcohol consumption; periodontal disease; systemic diseases that may interfere with the integrity of the oral mucosa; individuals with medical or pharmacological history that affect the performance of the study, family history of malignancies. For smokers the inclusion criterion was a minimum consumption of 20 cigarettes / day, and the contrast required for non-smokers. The sample was divided into 02 experimental groups: Group 1 Smokers and Group 2 Non-Smokers, both groups performed mouthwash (alcohol 21,6%) with Listerine® Defense of Teeth and Gums for 04 weeks cytological collection were performed on buccal mucosa and portion median border of the tongue, one for initial, week 0 control, and subsequent three weeks with continued use of mouthwash. The collected material was stained by specific staining Feulgen / Fast Green. The analysis of 3000 cells / individual was performed by light microscopy statistics used Kruskal- Wallis and Mann-Whitney tests for frequency MN. The frequency of micronuclei in buccal mucosa was 1.6 ± 1.75 and 1.46 ± 2.06 for the site language to Group 1 Smokers of showing a slight increase compared with Group 2 Non-smoking, which showed a variation of 1.2 ± 1.53 for the buccal mucosa site and 0.86 ± 1.41 for the site language. However, this difference was not statistically significant. The results suggest that alcohol-based mouthwash tested is not an inducer of genotoxic changes, thus not changing the frequency...

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)