Control of uncertain compartmental systems

Os sistemas compartimentais são frequentemente usados na modelação de diversos processos em várias áreas, tais como a biomedicina, ecologia, farmacocinética, entre outras. Na maioria das aplicações práticas, nomeadamente, aquelas que dizem respeito à administração de drogas a pacientes sujeitos a cirurgia, por exemplo, a presença de incertezas nos parâmetros do sistema ou no estado do sistema é muito comum. Ao longo dos últimos anos, a análise de sistemas compartimentais tem sido bastante desenvolvida na literatura. No entanto, a análise da sensibilidade da estabilidade destes sistemas na presença de incertezas tem recebido muito menos atenção. Nesta tese, consideramos uma lei de controlo por realimentação do estado com restrições de positividade e analisamos a sua robustez quando aplicada a sistemas compartimentais lineares e invariantes no tempo com incertezas nos parâmetros. Além disso, para sistemas lineares e invariantes no tempo com estado inicial desconhecido, combinamos esta lei de controlo com um observador do estado e a robustez da lei de controlo resultante também é analisada. O controlo do bloqueio neuromuscular por meio da infusão contínua de um relaxante muscular pode ser modelado como um sistema compartimental de três compartimentos e tem sido objecto de estudo por diversos grupos de investigação. Nesta tese, os nossos resultados são aplicados a este problema de controlo e são fornecidas estratégias para melhorar os resultados obtidos.

Comparação do efeito da técnica de facilitação neuromuscular proprioceptiva com a técnica de músculo energia no alongamento muscular dos isquiotibiais a curto prazo

Introdução: A aplicação das técnicas de Contrair-Relaxar com Contracção do Antagonista (CRCA) e de Músculo Energia (TME) promovem um aumento da flexibilidade muscular, contudo poucos estudos comparam a eficácia de ambas. Apresentam aspectos comuns como a contracção prévia do músculo a alongar sendo esta máxima na CRCA e uma percentagem da máxima na TME. Contudo, alguma evidência sugere que não existe correspondência entre a força produzida e a desejada pelo que este aspecto da TME carece de explicação. Objectivos: Confirmar se a técnica CRCA e a TME são efectivas no alongamento muscular dos isquiotibiais a curto prazo, caso sejam determinar qual a mais efectiva. Pretende-se ainda avaliar se a percepção ao esforço durante a aplicação da TME corresponde à força efectivamente realizada. Métodos: Efectuou-se um estudo experimental com 45 voluntários distribuídos aleatoriamente pelos grupos CRCA, TME e Controlo. Avaliou-se a amplitude articular passiva de extensão do joelho antes e depois de aplicar as técnicas, utilizando um goniómetro. Nos participantes submetidos à TME avaliou-se a percepção ao esforço, solicitando uma contracção submáxima isométrica de 40% medida através do dinamómetro de mão. Resultados: Verificou-se um efeito das técnicas entre as avaliações (Teste ANOVA medidas repetidas factor tempo: p<0,001) e entre os grupos (tempo*grupo: p<0,001). Comparando os grupos dois a dois, verificaram-se diferenças entre o grupo CRCA e o grupo Controlo (Teste Post Hoc Games-Howell: p=0,001) e entre o grupo TME e o grupo Controlo (p=0,009), não existindo diferenças entre os grupos CRCA e TME (p=0,376). Os grupos CRCA e TME obtiveram um ganho de 10,7º e de 11,4º respectivamente, não havendo diferenças significativas entre os ganhos (Teste T-Student Independente: p=0,599). Existiram diferenças significativas entre os 40% CMVI produzida e desejada (Teste Wilcoxon: p=0,018). Conclusão: Ambas foram efectivas no aumento da flexibilidade muscular dos isquiotibiais a curto prazo. Os efeitos foram comparáveis, mas dada a menor complexidade e menor solicitação a TME foi considerada mais eficiente. A percepção ao esforço durante a aplicação da TME não correspondeu ao esforço desejado, existindo uma tendência para a produção de intensidades de contracções maiores.

Proprioceptive Neuromuscular Facilitation of the Wrist Flexors

The present study examined a wrist extension-to-flexion contraction pattern that was theorized to result in proprioceptive neuromuscular facilitation. However, the “reversal of antagonists” contraction pattern may have, alternatively, interfered with motor learning-related increases in strength. Participants (N=24) were matched on predicted strength and randomly assigned to either the control or experimental group. Training occurred during three test sessions within a one-week period. Retention and transfer (crossed-condition) tests were administered during a fourth test session two- weeks later. Both groups exhibited comparable increases in strength (20.2%) and decreases in muscle coactivation (35.2%), which were retained and transferred. Decreases in error and variability of the torque traces were associated with parallel decreases in variability of muscle activity. The reversal of antagonists technique did not interfere with motor learning-related increases in strength and decreases in variability. However, the more complex contraction pattern failed to result in proprioceptive neuromuscular facilitation of strength.

The Influence of Cerebral Blood Flow and Carbon Dioxide on Neuromuscular Responses During Environmental Stress

Although reductions in cerebral blood flow (CBF) may be implicated in the development of central fatigue during environmental stress, the contribution from hypocapnia-induced reductions in CBF versus reductions in CBF per se has yet to be isolated. The current research program examined the influence of CBF, with and without consequent hypocapnia, on neuromuscular responses during hypoxia and passive heat stress. To this end, neuromuscular responses, as indicated by motor evoked potentials (MEP), maximal M-wave (Mmax) and cortical voluntary activation (cVA) of the flexor carpi radialis muscle during isometric wrist flexion, was assessed in three separate projects: 1) hypocapnia, independent of concomitant reductions in CBF; 2) altered CBF during severe hypoxia and; 3) thermal hyperpnea-mediated reductions in CBF, independent of hypocapnia. All projects employed a custom-built dynamic end-tidal forcing system to control end-tidal PCO2 (PETCO2), independent of the prevailing environmental conditions, and cyclooxygenase inhibition using indomethacin (Indomethacin, 1.2 mg·Kg-1) to selectively reduce CBF (estimated using transcranial Doppler ultrasound) without changes in PETCO2. A primary finding of the present research program is that the excitability of the corticospinal tract is inherently sensitive to changes in PaCO2, as demonstrated by a 12% increase in MEP amplitude in response to moderate hypocapnia. Conversely, CBF mediated reductions in cerebral O2 delivery appear to decrease corticospinal excitability, as indicated by a 51-64% and 4% decrease in MEP amplitude in response to hypoxia and passive heat stress, respectively. The collective evidence from this research program suggests that impaired voluntary activation is associated with reductions in CBF; however, it must be noted that changes in cVA were not linearly correlated with changes in CBF. Therefore, other factors independent of CBF, such as increased perception of effort, distress or discomfort, may have contributed to the reductions in cVA. Despite the functional association between reductions in CBF and hypocapnia, both variables have distinct and independent influence on the neuromuscular system. Therefore, future studies should control or acknowledge the separate mechanistic influence of these two factors.

Aplicaci?? de l'entrenament de la for??a al tennis : la import??ncia del control del moviment

Resumen tomado del autor. Contiene dibujos de los efectos de la pelota seg??n la forma en que se coge la raqueta

Neuromuscular dressing effects: a literature review

The kinesio taping is a technique that was created in 1979 by Doctor Kenzo Kase I’m looking through it that could generate a new therapeutic option to control pain, improve athletic performance and reduce the impact of musculoskeletal disorders. From the Sydney 2000 Olympic Games, this technique as a therapeutic alternative PTO and is composed of health professionals in the field of sport and physical rehabilitation. Objetive: This article aims to identify theoretical approaches on the bandage neuromuscular. Material and methods: held today, for which conducted a literature search of databases such as como Proquest, Ovid, Cochraine, PEDro, Journal ofOrthopedic and Sports Physical, Sciencedirect, Pubmed y Literatura Latinoamericana y del Caribe en Ciencias de la Salud (Lilacs). The paper proposes a scheme of contextualization of the current landscape of the use and effects of kinesio taping in the management of different pathologies of the musculo-skeletal system in sports. Conclusion: it is concluded that currently many health professionals, and take the neuromuscular bandage a good therapeutic option in the management of diseases affecting the human body is investigated and every day more about the subject, which makes these new therapeutic methods to acquire a scientific value and transcends knowledge.

Eficacia del vendaje neuromuscular en el tratamiento de la sialorrea en pacientes con trastorno del espectro autista

Resumen basado en el de la publicaci??n

Electromyographic Evaluation of Neuromuscular Coordination of Subject After Orthodontic Intervention

The aim of this work was to investigate the neuromuscular changes associated with the orthodontic post-treatment using surface electromyography. One hundred (100) young, healthy adults without signs and symptoms of temporomandibular dysfunction (TMD) were divided into two groups: 60 subjects who were undergoing orthodontic intervention (Ortho Group) and 40 subjects who had no orthodontic intervention (Control Group), aged 18-25 years. EMG activity of masseter and temporalis anterior muscle was recorded during two different tests: 1. maximum voluntary clench (MVC) with cotton rolls; and 2. MVC in intercuspal position. In all subjects, both tests were performed with symmetric muscular patterns (more than 85%) and with insignificant latero-deviating of the mandible (lower than 10%). There are no statistically significant differences between the subjects of both groups evaluated. Both groups showed medium index values calculated according to the normal standards established previously.

Modificações introduzidas pelos treinamentos cardiopulmonar e neuromuscular nos níveis séricos basais de fatores de crescimento insulina símile i (igf-1), cortisol, autonomia funcional e qualidade de vida de mulheres idosas

Changes introduced by cardiopulmonar and neuromuscular training on basal serum insulin-like grow factor-1 (IGF-1) and cortisol levels, functional autonomy and quality of life in elderly women The aim of this study was to compare the effects of strength and aerobic training on basal serum IGF-1 and Cortisol levels, functional autonomy (FA) and quality of life (QoL) in elderly women after 12 weeks of training. The subjects were submitted the strength training (75-85% 1-RM) with weight exercises (SG; n=12; age=66.08 ± 3,37 years; BMI=26,77 ± 3,72 kg/m2), aerobic training with aquatic exercises (AG; n=13; age=68,69 ± 4,70 years; BMI=29,19 ± 2,96 kg/m2) and control group (CG; n=10; age=68,80 ± 5,41 years; BMI=29,70 ± 2,82 kg/m2). Fasting blood was analyzed to measure basal IGF-1 and cortisol levels by chemiluminescence method. The t-Student test showed increased IGF-1 in the SG (p<0.05) for intragroup comparison. The Repeated-measure ANOVA presented increased IGF-1 (p<0.05) in the SG compared to the other two groups. There were no differences in cortisol levels. All the FA tests (GDLAM autonomy protocol) presented decreased significant in the time marked in seconds to the SG. The same results were found in the AG, except in the rise from a sitting position test. The autonomy index presented significant improvements (p<0.05) in the SG related to the AG and CG and in the AG to the CG. The SG showed increased QoL (p<0.05) (by WHOQOL-Old questionnaire) in the facet 1 (sensorial functioning) and facet 5 (death and dying). Thus, the SG obtained positive changes on IGF-1 and FA levels when compared to the AG. This suggests that strength training can indicated to decrease the effects of ageing.

Effects of two proprioceptive neuromuscular facilitation techniques in different planes on hamstrings muscles of healthy subjects

Introduction: The proprioceptive neuromuscular facilitation technique (PNF) has been proven to be efficient, since it was found higher gain of joint range-of-motion compared to the classic stretching. This study aimed to perform a comparison between the muscular stretching techniques and the PNF hold-relax on the internal and external sagittal/diagonal plane.Method: Randomly divided in 3 groups by a drawing, 30 healthy male individuals have undergone the test. In group I the hold-relax technique was utilized on the sagittal plane, grupo II receveid hold-relax on the internal and external diagonals, and group III, on which an evaluation was performed, worked as control. All the groups went through tests on the first, fifth and fifteenth day after the application of the different approaches. In this evaluation it was used a Flexis (R) Fleximeter.Result: Group II (diagonal) obtained statistically significant gain of 13.99% in the immediate post-test and post test later obtained a loss of 4.81%, group I (sagittal) showed no statistical difference as the group III (control).Conclusion: We conclude that the technique of PNF in the diagonal plane is effective in the flexibility of the hamstring muscles.

Efeito imediato da estimulação elétrica neuromuscular seletiva do músculo VMO em pacientes com síndrome da dor femoropatelar

Patellofemoral pain syndrome (PFPS) is described as anterior or retropatellar pain knee in the absence of other pathologies and is frequently associated with dysfunction of the vastus medialis oblique (VMO). However, several studies have demonstrated the inability to selectively activate this muscle through exercise. To evaluate the effect of Neuromuscular Electrical Stimulation (NMES) selective VMO in women with syndrome. We evaluated thirty-eight women: twenty in the control group (24.15 ± 2.60 years) and eighteen diagnosed with PFPS (25.56 ± 3.55 years). Both groups were evaluated before and after a protocol of electro stimulation. To measure for comparing groups before and after treatment, we assessed the extensor torque concentric and eccentric knee through an isokinetic dynamometer, the intensity (Root Mean Square - RMS) and the onset of activation (onset) of VMO compared to the vastus lateralis (VL) in two types of exercise: open and closed kinetic chain. . Statistical analysis was performed using SPSS 15.0, with a significance level of 5%. Results: Our data showed an increase in the intensity of activation (RMS) of the VMO muscle after NMES in both study groups. During concentric contraction the RMS of the VMO before the NMES was 105.69 ± 32.26 μV and after a single intervention was 122.10 ± 39.62 μV (p = 0.048) for the control group. In the group with PPS, we found a similar behavior, with RMS of the VMO before NMES of 96.25 ± 18.83 μV and 139.80 ± 65.88 μV after the intervention (p = 0.0001). However, there was no evidence in the RMS value of VL muscle. The onset was calculated by subtracting the onset of VL by the onset of VMO. For the group with PFPS, the onset before the intervention was -0.007 ± 0.14 ms, indicating a delay of the VMO relative to VL, and after NMES was 0.074 ± 0.09 ms (p = 0.016), showing an activation previous VMO to VL. The same occurred for the control group. We also observed that NMES increased knee extensor power during the concentric contraction in both groups. Before the intervention the mean power was 28.97 ± 9.01 W for the PPS group and after NMES was 34.38 ± 7.61 W (p = 0.0001). Conclusion: We observed an increase in electromyographic activity of the VMO and also an anticipatory effect of this muscle

Influência do kinesio taping® no desempenho neuromuscular do quadríceps femoral e na função do membro inferior em sujeitos saudáveis: ensaio clínico, controlado, randomizado, cego

Objective:To analyze the immediate effects of the Kinesio Taping® application on the quadriceps neuromuscular performance, postural balance and lower limb function in healthy subjects. Materials andmethods:This is a randomized, controlled, blinded clinical trial. Sixtyfemale volunteers(age: 23.3±2.5 years old, BMI: 22.2±2.1kg/m2)wererandomly assigned intothreegroups with20memberseach,and performedone of these threeprotocols: control -10 minutesof rest,experimental 1- patch application ontherectusfemoris (RF), vastuslateralis(VL) and vastusmedialis(VM) and experimental 2-KT application on the same muscles. Allunderwent an evaluationfor singleand triple hop distance, postural balance (baropodometry), joint position sense(JPS), peak torque (concentric and eccentricevaluation at 60°/s)and electromyographic activityof VL,before andafter intervention.Results: There wasasignificant increasein the jump distanceof thethreestudied groups,with no differencebetween groups.There were nosignificant changesin postural balance,JPS, concentricpeak torqueand RMSof the VLin none of the groups. There was a reduction ineccentricpeak torquein all groups, without differencesbetween groups.Conclusion:The KT application on the RF, VL and VMmusclesis not able tosignificantly improvelower limbfunction and postural balance, as well as the kneeextensor peaktorque, JPSand the VL muscleactivation amplitudeof healthy women.

Efeito do tempo de repouso após fadiga induzida no desempenho neuromuscular do quadríceps femoral: ensaio clínico, controlado, randomizado, cego

Objective: To evaluate the effect of different resting periods, after induced muscle fatigue, in the quadriceps femoris neuromuscular performance, in healthy subjects. Methods: Sixty-four volunteers, of both genders, with an average of 21,8 ± 1,7 years and mean body mass index of 24,2 ± 3,7 Kg/m2 were randomly assigned into 4 groups: control group (was not induced fatigue); Experimental Group 1 (Exp. 1 1 minute of rest after fatigue); Experimental Group 3 (Exp. 3 3 minutes of rest after fatigue) and Experimental Group 5 (Exp. 5 5 minutes of rest after fatigue). The subjects were evaluated to the knee´s joint position sense (JPS), followed by 5 flexion-extension knee concentric isokinetic contractions at 60°/s, with concomitant recording of median frequency (Fmed) of rectus femoris (RF), vastus lateralis (VL) and vastus medialis (VM). Then they underwent a muscle fatigue protocol (30 flexion-extension knee concentric contractions at 60°/s) and were reevaluated on the isokinetic performance, Fmed and JPS. Blood lactate levels were measured before initial assessment, immediately after the fatigue protocol and 5 minutes after the end of the rest period. Results: The adoption of 3 minutes of rest was sufficient to restore the initial conditions for the peak torque normalized by body weight and the VL and VM Fmed. The joint position sense returned to its initial values with 1 minute rest. The lactate concentration remained high regardless of the adopted rest period. Conclusion: The use of 3-minute rest period is sufficient for the reestablishment of the neuromuscular parameters to the pre fatigue values.

Efeitos imediatos da laserterapia sobre o desempenho neuromuscular após fadiga muscular induzida: ensaio clínico controlado, randomizado e cego

The aim of this study was to investigate the immediate effects of laser therapy on neuromuscular performance in healthy subjects after a muscle fatigue. This is a clinical trial, controlled, randomized, blinded, attended by 80 volunteers of both genders, healthy, with ages between 18 to 28 years. Initially the volunteers performed an initial evaluation (EV1) using electromyography in the biceps muscle, associated with assessment in isokinetic dynamometry with 5 concentric contractions (60 °/s) for elbow flexion. The subjects were randomly allocated into 4 groups: G1 (control, n = 20), G2 (placebo, n = 20), G3 (pre-fatigue laser, n = 20), and G4 (post fatigue laser, n = 20). The muscular fatigue protocol had 30 concentric isokinetic contractions (120 °/s). We used a 808 nm laser, power of 100 mW, applied at the belly of the biceps muscle. After the speeches the volunteers performed a final evaluation (EV2). Test was applied to two-way ANOVA with post hoc Turkey, with a significance level of 5%. There was no significant difference in electromyographic evaluation. In dynamometric evaluation showed a drop in peak torque, peak torque normalized to body weight (p <0.001) and average power (p <0, 05) between the initial and final evaluations in control. Among the groups there was a significant difference between the control and the other groups in relation to peak torque (p <0.05), peak torque to body weight (p <0.001) and average power (p <0.05). Therefore, the low intensity laser therapy does not alter the immediate neuromuscular performance after fatigue

Morphometric and morphological analysis of neuromuscular junction alterations in the denervated rat diaphragm

The morphological and structural alterations that occur in the neuromuscular junctions of the denervated rat diaphragm were studied. Fifteen adult male albino rats (Rattus norvegicus) aged about 60 days and with a mean weight of 200 g were used. Chronically denervated diaphragms were obtained and the animals were sacrificed after 4, 8 and 12 weeks of denervation. The left antimere of the diaphragm was denervated by section of the phrenic nerve and the right antimere was used as control. Each antimere was divided into three fragments: one was used for histochemical (nonspecific esterase) and morphometric study of neuromuscular junctions, and the other two were used for transmission and scanning electron microscopy (SEM) analysis. Histochemical analysis of the diaphragm neuromuscular junctions after denervation showed only small changes in junction morphology. However, these junctions became smaller and elongated and presented less visible contours with increasing time of denervation. Ultrastructural analysis of neuromuscular junctions after 12 weeks showed more or less organized junctional folds on the muscle fiber surface. The junctional cytoplasm exhibited important alterations such as mitochondrial degeneration and the presence of numerous filaments. SEM revealed the presence of deep primary synaptic grooves with peripheral excavations which housed the nerve terminal boutons and exhibited internally the secondary synaptic clefts present among the junctional folds of the sarcolemma. This study showed that some of the morphological changes demonstrated in other denervated striated skeletal muscles are not repeated at the same intensity or in the same temporal pattern in the rat diaphragm.