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Síndrome da dor femoropatelar análise eletromiográfica, isocinética, ressonância magnética, dor e fadiga
(Universidade Federal de São Carlos, 2005-03-22) Souza, Alessandra de Castro; Pedro, Vanessa Monteiro; https://lattes.cnpq.br/4302307099019276; SOUZA, A. C.
The purpose of this work was to analyze the electrical activity (EMG) of the vastus medialis obliquus (VMO) and vastus lateralis longus (VLL) and vastus lateralis obliquus (VLO) in association with the evaluation of the maximum isometric torque (MIT) of the quadriceps muscle, during the maximum voluntary isometric contraction (MVIC) of knee extension in open kinetic chain (OKC) at 20o, 30o, 50o and 60o of knee flexion, also, pain and fatigue and the aspects in relation to patellae positioning: the sulcus angle (SA), the congruence angle (CA), patellar tilt angle (PTA) and lateral patellar displacement (LDP). Twenty four female subjects were evaluated (12 with patellofemoral pain syndrome PFPS and 12 clinically normal controls). For the EMG analysis simple surface differential active electrodes and a Signal Conditioner Module (MCS 1000-v2) were used. The electromyographic signal was quantified by the Root Mean Square (RMS), in µV, and normalized by the MVIC of 90o of knee extension. The subjects made 5 MVIC of knee extension, at 30o of flexion for the EMG and MMIT analysis and the NMRI with the quadriceps muscle relaxed were obtained at the same angles. The following statistic tests were used: ANOVA Analysis of Variance with Repeated Measurements for the EMG and MMIT analysis; the Mann-Whitney U test for the NMRI; and the One Way Analysis of Variance for the evaluation of intensity and discomfort from pain and fatigue (p ≤ 0.05). The results showed a higher electrical activity of the VLL muscle in relation to the VMO in the group with FPPS. The control group, the VMO and VLL did not present a significant difference in all studied angles. In both groups, VMO and VLL showed a higher electrical activity in comparison with VLO, in all angles. The MMIT values of the quadriceps did not differ among groups, however it did differ between angles. The highest MMIT value was 60o. The NMRI analysis revealed that the FPPS group presented higher values of SA and lower values of CA in relation to the Control group. The results showed an increase in pain and fatigue of the subjects with PFPS after the MVIC and in comparison with the Control group. The data of this study, on the experimental conditions, suggest that: a higher electrical activity of the VLL in addition with the increase in SA and decrease in CA in the subjects with PFPS can be factors favoring such individuals patellar instability. Pain and fatigue were greater in subjects with PFPS. The results showed that the EMG and the NMRI were instruments capable of differentiating the groups that were studied.
Filtração de gases: estudo do fenômeno da limpeza por blocos
(Universidade Federal de São Carlos, 2005-03-22) Tieni, Érica Flávia; Aguiar, Mônica Lopes; https://lattes.cnpq.br/0431688649128529
This work had for purpose to study the phenomenon of patchy cleaning in the operation of the gas filtration, which happens when there is the incomplete regeneration of the filter. A parameter very used to characterize this henomenon it is the cleaned fraction, which is defined as the ratio between the cleaned areas to the total area of filtration. In order to investigate the atchy cleaning behavior, filtration experiments were accomplished, with the intention to study the action of the cleaning in the fabric of polyester, for different combinations of experimental conditions. To characterize the cleaning for blocks, it has been developed a methodology that includes imagining of the blocks and computer program that analyzes these images of the cake at the end of each cleaning cycle. Using these images it was possible to mark the areas removed with the aim to obtain the size of the removed blocks. The general results showed that: for the maximum pressure drop of 1960 Pa, the fabric presented saturation behavior starting from the second filtration cycle, and for the maximum pressure drop 2939 and 3919 Pa, starting from the fourth filtration cycle. Unlike what was expected, the maximum cleaning velocity was not the one that gives the maximum removal of the cake. The residual pressure drop showed relationship with the distribution of the sizes of the removed blocks. Concerning the quantification of the removed blocks, the removed total area did not present defined behavior with the number of cycles. The largest percentage of the removed blocks presented size between 0,1 e 1 cm2. The area fractions and mass fractions removed presented curves with similar behavior. Besides, the two fractions presented very close values to each other, showing that the technique proposed in this work of quantification of the size of the removed areas presented quite satisfactory results.
Estudo por espectroscopia Raman de efeitos de localização das excitações elementares em superredes e em ligas dopadas
(Universidade Federal de São Carlos, 2005-03-22) Carrasco, Veronica Elsa Espinoza; Galzerani, José Cláudio; https://lattes.cnpq.br/2448874919199274; Pusep, Yuri
In the present work, the localization properties of the single-particle and collective excitations subjected to a random potential in the AlGaAsSi alloys and in the intentionally disordered GaAs/AlGaAs:Si superlattices (SL s)were investigated by magnetoresistance and Raman scattering. As it is well known, the fluctuations of the eletronic potential, which occur in doped SL s and alloys destroy the translational invariance giving rise to a spatial coherence length of the elementary excitations and, as consequence, cause the breakdown of the Raman selection rules leading to the broadening and assymetry of the Raman lines. The analysis of the shape of the spectral lines allows one to determine the coherence lengths of the elementary excitations involved in the Raman process and thus, to study their localization properties. It was shown that the Landau damping determines the localization lengths of the collective plasmon-like excitations in bulk AlGaAs alloy. Meanwhile the localization lengths of both,the single-particle and collective excitations are limited by disorder in the intentionally disordered superlattices. The localization lengths of the plasmon-like excitations obtained by Raman Spectroscopy was compared with the phase-breaking lengths measured by Magnetoresistance. We had verified that in superlattices the localization length of the individual electron was found to be considerably larger than localization length corresponding to the collective excitations. This suggests that the effect of disorder has weaker influence on the electrons than on their collective motion and that the interaction, which gives rise to the collective effects, increase the localization.