463 resultados para regularity


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A percepção subjetiva de esforço (PSE) é determinada de forma não invasiva e utilizada juntamente com a resposta lactacidêmica como indicadores de intensidade durante teste incremental. em campo, especialmente na natação, há dificuldades nas coletas sanguíneas; por isso, utilizam-se protocolos alternativos para estimar o limiar anaeróbio. Assim, os objetivos do estudo foram: prescrever um teste incremental baseado na PSE (Borg 6-20) visando estimar os limiares metabólicos determinados por métodos lactacidêmicos [ajuste bi-segmentado (V LL), concentração fixa-3,5mM (V3,5mM) e distância máxima (V Dmáx)]; relacionar a PSE atribuída em cada estágio com a freqüência cardíaca (FC) e com parâmetros mecânicos de nado [freqüência (FB) e amplitude de braçada (AB)], analisar a utilização da escala 6-20 na regularidade do incremento das velocidades no teste e correlacionar os limiares metabólicos com a velocidade crítica (VC). Para isso, 12 nadadores (16,4 ± 1,3 anos) realizaram dois esforços máximos (200 e 400m); os dados foram utilizados para determinar a VC, velocidade de 400m (V400m) e a freqüência crítica de braçada (FCb); e um teste incremental com intensidade inicial baseada na PSE, respectivamente, 9, 11, 13, 15 e 17; sendo monitorados em todos os estágios a FC, lactacidêmia e os tempos de quatro ciclos de braçadas e das distâncias de 20m (parte central da piscina) e 50m. Posteriormente, foram calculadas as velocidades dos estágios, FB, AB, V LL, V3,5mM e V Dmáx. Utilizaram-se ANOVA e correlação de Pearson para análise dos resultados. Não foram encontradas diferenças entre VC, V Dmáx e V LL, porém a V3,5mM foi inferior às demais velocidades (P < 0,05). Correlações significativas (P < 0,05) foram observadas entre VC versus V400m, V Dmáx e V3,5mM; V400m versus V3,5mM e V Dmáx; V Dmáx versus V LL; e no teste incremental entre PSE versus velocidade, [Lac], FC, FB e AB (P < 0,05). Concluímos que a PSE é uma ferramenta confiável no controle da velocidade dos estágios durante teste incremental na natação.

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Background: The gait automaticity loss difficults realization of concurrent activities - Dual Task (DT). In these situations, individuals with Parkinson`s disease (PD) show a significant reduction in gait velocity and stride length, as strides variability and asymmetry increased, factors predisposing to falls. However, recent studies have shown that training involving DT may cause subsequent improvements in gait variables with DT in individuals with PD. The treadmill use was adopted by this study, by promoting greater regularity in step and enhance training. Objective:To investigate immediate effects of gait training associated with cognitive tasks on gait in individuals with PD. Methods: Twenty-two volunteers were randomly divided into two groups: control group (n = 11), who performed gait training on a treadmill for 20 minutes, and the experimental group (n = 11), who performed treadmill gait training for 20 minutes associated with cognitive tasks of verbal fluency, memory, and spatial planning. Participants were evaluated in phase on of antiparkinsonian medication as the demographic, clinical and anthropometric (identification form), cognitive status (Montreal Cognitive Assessment - MoCA), executive function (Frontal Assessment Battery), level of physical disability (Hoehn and Yahr Modified), motor and functional status (Unified Rating Scale for Parkinson`s Disease - UPDRS), and kinematics (Qualisys Motion Capture System). Results: There were not differences between groups, but both showed improvement after the intervention. The control group had an increase in velocity (p = 0.008), stride length (p = 0.04), step length (p = 0.02) and decreased double support time(p = 0.03). The experimental group showed an increase in speed (p = 0.002), stride length (p = 0.008), step length (p = 0.02) and cadence (p = 0.01), as well as a decrease in the width stride (p = 0.001) and total support time (p = 0.02). As the angular variables, the experimental group had a significant increase in the initial contact angle of ankle (p = 0.01). Conclusion: The gait training combined with cognitive activities didn`t provide significant improvements in gait variables with DT, but this study was the first to demonstrate that gait training on treadmill as simple task minimized the negative interference of DT in PD

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Oral and facial bone defects can undertake appearance, psychosocial well-being and stomathognatic function of its patients. Over the yerars several strategies for bone defect regeneration have arised to treat these pathologies, among them the use of frozen and irradiated bone allograft. Manipulation of bone grafts it s not determined yet, and several osteotomy alternatives can be observed. The present work evaluated with a microscope the bone fragments obtained from different osteotomy methods and irrigation on rings and blocks allografts irradiated and frozen at 80° negative in a rabbit model. The study is experimental in vitro and it sample was an adult male New Zealand rabbit. The animal was sacrificed to obtain long bones, that were submitted to freezing at 80º negative and irradiated with Cobalt- 60. Then the long bones were sectioned into 24 bone pieces, divided into 4 groups: G1 (n=06) osteotomy was performed with bur No. 6 forming rings with 5 mm thickness with high-speed handpiece with manual irrigation; G2 (n=06) osteotomy was performed with bur No. 6 forming rings with 5 mm thick with surgical motor with a manual irrigation rotation 1500 rpm; GA (n=06), osteotomy with trephine using manual irrigation with saline; and GB (n=06), osteotomy with trephine using saline from peristaltic pumps of surgical motor. Five bone pieces of each group were prepared for analysis on light microscopy (LM) and one on electronic scan electronic microscopy (SEM). On the SEM analysis edges surface, presence of microcracks and Smear Layer were evaluated. Analyzing osteotomy technics on SEM was observed: increased presence of microcracks cutting with high speed; increased presence of areas covered by Smear Layer when cutting with motor implant. The irrigation analysis with SEM was observed: that the presence of microcracks does not depend on the type of irrigation; on manual irrigation, there was greater discrepancy between the cutting lines. The descriptive analysis of the osteotomy and irrigation process on LM showed: histological analysis showing the bony margins with clear tissue changed layer, composed of blackened tissue of charred appearance near to the cortical bone; on the edges of the bony part, bone fragments that were displaced during the bone cut and bone irregularities were observed. After analysis of results we can conclude: that there was greater regularity of the bone cut using high-speed handpiece than using motor implant; the cut with trephine using saline irrigated from peristaltic pumps of surgical motor showed greater homogeneity when compared with manual irrigation; charred tissue was found in all obtained bone samples, whit no significant statistically difference on the proportion of carbonization of the two analysed technics

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The sleep is an active brain process that allows the efficient realization of daily tasks. The changes on sleep patterns may influence the different cognitive processes performance. Many recent studies show the possibility of cognitive performance improvement, through the cognitive training with the use of computer games. The question is if these interventions may be influenced by the sleep quality. Thus, we evaluated the sleep quality effect about the efficacy of an intervention with computers games based on the working memory and attention for a cognitive performance training of elementary school students. The sample was constituted by 42 students with average age of 10,43 years old (SD=1,23), with 22 male participants and 20 female participants. We used to evaluate the sleep with the parents a sleep questionnaire, a sleep diary and the Sleep Behavior Questionnaire. In regard to intervention, the subjectives were distributed in an experimental and in a control group, both with 21 participants. In the first group occurred the intervention that consisted in the working memory and attention training with two cognitive tasks (Safari e Brain Workshop) during 30 daily minutes, for a 6 weeks period. In an equal period, the students from the control group should reproduce an artwork using drawing software. To evaluate the cognitive performance we applied before and after the intervention period the Wechsler Intelligence Scale for Children (WISC-III). The results showed that in both the groups the performance of the intelligence, working memory, attention and visuospatial skills was below of the mean. The cognitive processes evaluated after of intervention in the experimental group had a performance significantly higher in the Perceptual Reasoning Index (t = -6,24; p < 0,01) and in the Full Scale IQ (t = -5,09; p < 0,01) and Performance IQ (t = -6,52; p < 0,01), suggesting a improvement on the visuospatial skills, attention, working memory and processing speed. On the control group, the performance was significantly higher in the Coding subtest (t = -5,38; p< 0,01) and in the Perceptual Reasoning Index (t = -3,66; p = 0,01), suggesting a improvement on the visuospatial skills and attention. The mean obtained with the Sleep Behavior Questionnaire was 53,76 (SD=14,96) for an experimental group and 61,19 (SD=12,82) for a control group, indicating tendency for a bad sleep quality in that last one. Not only during the first days, but also in the last fifteen days of the intervention we verified in the two groups an adequate time to sleep, duration and regularity, in the weekdays and on the weekends. We didn t find significant differences between the two groups in none of the sleep variables. We verified statistically meaningful improvement on the performance of the experimental group with the intervention in the two games. We didn t verify significant correlations between the games performance index and in the sleep variables of the experimental group individuals. We verified significant correlations among the performance on the Brain Workshop and the Cubes subtest, the Perceptual Reasoning Index and the Scale Performance IQ, suggesting that the significant improvement of the visuospatial skills and of the attention was correlated with the performance in the Brain Workshop. Although the absence of correlations with the performance in the Safari, possibly it also has relieved in the improvement of the cognitive performance. The findings support the hypothesis that the computer games might be a satisfactory tool for the improvement of the performance in visuospatial skills and attention. This can be resulted of the insertion of visuospatial stimulations in the task, for example, graphical elements with thematic for children that increase the interest. The IQ below mean the individuals might have influenced the improvement absence on the cognitive processes like the working memory with games. Moreover, it wasn t verified a relation between the sleep quality and the intervention efficacy. It might have been influenced by the n of the sample. Future studies must focalize in the improvement of the effect of the interventions with games

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Shift work consists of an array of unusual work hours, such as evenings and weekends, and increasing workload, in order to meet the uninterrupted production, which leads to changes in the quality, duration and regularity of sleep. Research indicates that sleep alteration cause cognitive processes to become slower, unstable and prone to errors, leading to loss of cognitive functions such as visuospatial perception. In this sense, this research aimed to evaluate sleep quality and its relation to visuospatial perception in workers in alternating shifts. Participants were 21 panel operators in a petrochemical company, male, aged 19-53 years. All participants were subjected to schedules of alternating shifts (day and night) of 12 nonstop hours and data were collected from 10 workers who were assigned to the day shift and 11 workers assigned to the night shift. For the sleep evaluation were used the Sleep Diary, the Sleep Habits Questionnaire, the Chronotype Identification Questionnaire and the Pittsburgh Sleep Quality Index (PSQI). The visuospatial skills were assessed using the Rey Complex Figure Test and attention was assessed using a portable version of the Psychomotor Vigilance Task (PVT). The results showed that the general sample of workers obtained poor sleep quality on working days and good sleep quality during the work break. There was shortened sleep duration in the work week and appropriate duration in the work break. No losses were found in the workers visuospatiality, but the good quality of sleep during the work break was correlated to adequate visuospatial performance, for the day shift workers. The attention performance oscillated throughout the work hours, especially on the night shift. It is concluded that the alternating shifts work scheme can be detrimental to the sleep quality workers and a good sleep quality can contribute to a better visuospatial performance

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In general, an inverse problem corresponds to find a value of an element x in a suitable vector space, given a vector y measuring it, in some sense. When we discretize the problem, it usually boils down to solve an equation system f(x) = y, where f : U Rm ! Rn represents the step function in any domain U of the appropriate Rm. As a general rule, we arrive to an ill-posed problem. The resolution of inverse problems has been widely researched along the last decades, because many problems in science and industry consist in determining unknowns that we try to know, by observing its effects under certain indirect measures. Our general subject of this dissertation is the choice of Tykhonov´s regulaziration parameter of a poorly conditioned linear problem, as we are going to discuss on chapter 1 of this dissertation, focusing on the three most popular methods in nowadays literature of the area. Our more specific focus in this dissertation consists in the simulations reported on chapter 2, aiming to compare the performance of the three methods in the recuperation of images measured with the Radon transform, perturbed by the addition of gaussian i.i.d. noise. We choosed a difference operator as regularizer of the problem. The contribution we try to make, in this dissertation, mainly consists on the discussion of numerical simulations we execute, as is exposed in Chapter 2. We understand that the meaning of this dissertation lays much more on the questions which it raises than on saying something definitive about the subject. Partly, for beeing based on numerical experiments with no new mathematical results associated to it, partly for being about numerical experiments made with a single operator. On the other hand, we got some observations which seemed to us interesting on the simulations performed, considered the literature of the area. In special, we highlight observations we resume, at the conclusion of this work, about the different vocations of methods like GCV and L-curve and, also, about the optimal parameters tendency observed in the L-curve method of grouping themselves in a small gap, strongly correlated with the behavior of the generalized singular value decomposition curve of the involved operators, under reasonably broad regularity conditions in the images to be recovered

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O apuim-de-costas-pretas [Touit melanonotus (Wied, 1820)] é uma espécie florestal endêmica da Mata Atlântica Brasileira e de relevante interesse conservacionista. Trata-se de uma ave com poucas informações disponíveis acerca de sua história natural e distribuição geográfica e novas observações são importantes fontes de informação para auxiliar na conservação da espécie. Aqui reavaliamos o primeiro registro da espécie e apresentamos novas observações no estado do Paraná, sul do Brasil. As vocalizações atribuídas a T. melanonotus e que consubstanciaram sua ocorrência no estado foram examinadas com auxílio de espectrogramas e identificadas como vozes de Pionopsitta pileata (Scopoli, 1769). Não obstante, T. melanonotus ocorre com certa regularidade no Paraná, como indicado por novos registros da espécie em sete localidades distribuídas por todo o litoral do estado. Esta ave foi registrada principalmente em florestas de terras baixas e, uma vez que esta fisionomia sofre intensas pressões antrópicas, sugerimos que esforços de conservação da espécie devem priorizar a preservação desses hábitats.

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Estudos fenológicos de longa duração em florestas tropicais são raros. Foi realizado o acompanhamento fenológico de Dipteryx odorata, no período de 1974 à 2000, em duas áreas de floresta amazônica: a Reserva Florestal Ducke (RFD) e Estação Experimental de Silvicultura Tropical (EEST). O objetivo foi observar os padrões fenológicos nas duas áreas, verificar a regularidade da floração e frutificação num período de 27 anos e a influência dos fatores climáticos nestes eventos. Foram marcados cinco indivíduos na RFD e cinco na EEST e observados quanto à produção de flores, frutos imaturos e maduros. A floração e a produção de frutos imaturos apresentaram padrão irregular nas duas áreas observadas, variando quanto a época de ocorrência e a duração entre anos e estações, mas apresentaram freqüência de ocorrência similar nos 27 anos observados. Para a fenofase frutos maduros este padrão foi diferente, com intervalos de até três anos sem ocorrência de frutos maduros, na RFD e de sete anos na EEST. Conclui-se que a freqüência de ocorrência das fenofases de floração e frutos imaturos foi anual e a de frutos maduros supra-anual, todas com padrão irregular e duração de intermediária a prolongada. Ocorreu variação de um a três anos entre episódios de floração e frutos imaturos e de um a sete anos entre episódios de frutos maduros, não ficando evidente, nesta análise, a influência dos fatores climáticos nos padrões observados. Sugere-se o uso racional dos produtos derivados de Dipteryx odorata, o cumaru, especialmente quanto à exploração de seus frutos e o desenvolvimento de mais estudos de longa duração, fundamentais para entender os padrões fenológicos reprodutivos e de oferta de recursos em florestas tropicais.

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

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Testicles of 30 mongrel cats were analyzed histologically and morphometrically, divided into three groups: G1 (1-2 years old), G2 (over 2 and up to 4 years old) and G3 (over 4 and up to 6 years old). After orchiectomy and histopathology, the morphometric parameters studied were: thickness of the tunica albuginea (72 mu m) and seminiferous epithelium (77.19 mu m), perimeter (53.81; 90.57 mu m), (54.80; 101.07 mu m); area (174.23; 494.55 mu m(2)), (176.68; 629.70 mu m(2)); maximum diameter (14.94; 28.02 mu m), (14.76; 31.66 mu m); minimum diameter (13.25; 21.92 mu m), (13.30; 24.52 mu m); and shape factor (index for regularity of the format) (1.36; 1.36), (1.39; 1.35) of the nucleus and cytoplasm of spermatogonia and Leydig cells, respectively. The results can be used for comparative studies and contribute knowledge concerning the height of the seminiferous epithelium, thickness of the tunica albuginea and size of spermatogonia and Leydig cells.

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The Birkhoff-Gustavson normal form is employed to study separately chaos and resonances in a system with two degrees of freedom. In the integrable regime, tunnelling effects are appreciable when the nearest level spacings show oscillations. Tunnelling among states in the libration and rotation tori regions is also observed. The regularity of avoided crossings due to tunnelling indicates a collective effect and is associated with an isolated resonance. The spectral fluctuations also show a strong level correlation. The Husimi distribution, on the other hand, is insensitive to avoided crossings. An integrable approximation to the overlap of resonances is obtained and a theoretical description is given for an isolated cubic resonance plus a complex orbit. In the non-integrable regime chaos is stronger after overlapping and preferentially at low energies.

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OBJECTIVE: To evaluate the effects of 2 different doses of exogenous surfactant on pulmonary mechanics and on the regularity of pulmonary parenchyma inflation in newborn rabbits. METHOD: Newborn rabbits were submitted to tracheostomy and randomized into 4 study groups: the Control group did not receive any material inside the trachea; the MEC group was instilled with meconium, without surfactant treatment; the S100 and S200 groups were instilled with meconium and were treated with 100 and 200 mg/kg of exogenous surfactant (produced by Instituto Butantan) respectively. Animals from the 4 groups were mechanically ventilated during a 25-minute period. Dynamic compliance, ventilatory pressure, tidal volume, and maximum lung volume (P-V curve) were evaluated. Histological analysis was conducted using the mean linear intercept (Lm), and the lung tissue distortion index (SDI) was derived from the standard deviation of the means of the Lm. One-way analysis of variance was used with a = 0.05. RESULTS: After 25 minutes of ventilation, dynamic compliance (mL/cm H2O.kg) was 0.87 +/- 0.07 (Control); 0.49 +/- 0.04 (MEC*); 0.67 +/- 0.06 (S100); and 0.67 +/- 0.08 (S200), and ventilatory pressure (cm H2O) was 9.0 +/- 0.9 (Control); 16.5 +/- 1.7 (MEC*); 12.4 +/- 1.1 (S100); and 12.1 +/- 1.5 (S200). Both treated groups had lower Lm values and more homogeneity in the lung parenchyma compared to the MEC group: SDI = 7.5 +/- 1.9 (Control); 11.3 +/- 2.5 (MEC*), 5.8 +/- 1.9 (S100); and 6.7 +/- 1.7 (S200) (*P < 0.05 versus all the other groups). CONCLUSIONS: Animals treated with surfactant showed significant improvement in pulmonary mechanics and more regularity of the lung parenchyma in comparison to untreated animals. There was no difference in results after treatment with either of the doses used.

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Quaternionic theory has greatly been developed in recent years [1-12]. Thus, in our view, the study of trigonometric and logarithmic type quaternionic functions is important for the determination and realization of a hyper complex theory. In this paper, we intend to give a geometrical foundation for both logarithmic and trigonometric hyper complex functions based on the exponential function of quaternionic type recently introduced by Borges, Marão and Machado in their paper entitled Geometrical octonions II: Hyper regularity and hyper periodicity of the exponential function appearing. © 2011 Pushpa Publishing House.

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This article aims to investigate the abbreviations used on chats by web-surfers between 15 and 20 years old. The material consists of two virtual conversations of about 60 minutes each. We believe that this linguistic process occurs due to the physical distance that separates affectively the web-surfers by modifying already said utterances in written practices characterized by short time of interaction. This abbreviation process, known as a characteristic of the so called internetês, is not considered as a simple attempt to cut the words, but as a resource that presents linguistics' regularity. Therefore, the theory of phonological syllable is used as a tool in order to verify the process that forms possible abbreviations used on chats. It is believed that, based on the study of the syllable structure, the choice of the graphemes abbreviation may be assessed based on the writing heterogeneity, since the writer might not only use oral/spoken practices but also literate/written ones so as to produce utterances that emerge in the contemporaneity.

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Includes bibliography