Influência da atividade muscular abdominal na velocidade do oi tsuki

Introdução: No karaté a região lombo pélvica é importante, pois permite dar estabilidade e potenciar a força produzida na aplicação de técnicas de karaté. Apesar disso, nenhum estudo estuda a influência da atividade muscular abdominal na velocidade de aplicação de técnicas. Existem diversos estudos sobre o karaté mas nenhum deles foca a importância da atividade muscular abdominal. Objetivo: O objetivo deste estudo é verificar se o timing e a magnitude de ativação dos músculos abdominais influenciam a velocidade aplicada na técnica de karaté oi tsuki. Metodologia: Estudo transversal analítico com 7 praticantes de karaté do sexo masculino com graduação de 3º kyu (1º nível de cinturão castanho) ou superior. Foi avaliado o timing e a magnitude de ativação muscular abdominal com eletromiografia de superfície e a velocidade de movimento com sistema Qualisys, durante a execução do oi tsuki. Para dados estatísticos realizou-se o teste de spearman (nível de significância de 0,05) para testar correlação entre timing e a velocidade e entre magnitude de ativação e a velocidade, recorrendo ao coeficiente de determinação para verificar o grau de correlação. Para verificar diferenças bilaterais entre os timings e a magnitude de ativação dos músculos abdominais realizou-se o teste de Wilcoxon (nível de significância de 0,05). Resultados: Foi observada uma relação estatisticamente significativa (p< 0,05) entre o timing de ativação dos músculos transversos/oblíquos internos abdominais e do oblíquo externo contra lateral com a velocidade média do oi tsuki. Os timings de ativação dos músculos retos abdominais e oblíquo externo ipsilateral não revelaram valores de significância (p> 0,05) que possibilitem afirmar que existe relação entre esses timings e a velocidade média do oi tsuki. Não existem valores estatisticamente significativos (p> 0,05) para afirmar que existe relação entre a magnitude de ativação dos músculos abdominais e a velocidade média do oi tsuki. A velocidade máxima do movimento não foi afetada nem pelos timings de ativação dos músculos do abdómen, nem pelas suas magnitudes de ativação. Apenas o timing entre os músculos Transversos/oblíquos internos contra lateral e ipsilateral revelou diferenças. Conclusão: O tronco evidencia ser importante para a prática do karaté, não só pela melhoria da performance, mas também pela melhoria de estabilidade e consequente técnica. Apresenta uma aparente melhoria na velocidade inicial da técnica, podendo afetar positivamente a performance. Para além da performance, contribui para a segurança das estruturas lombo pélvicas, promovendo um menor risco de lesão.

Sleep disorders in boys with Duchenne muscular dystrophy.

Aim:  Determine the frequency and predictors of sleep disorders in boys with Duchenne Muscular Dystrophy (DMD). Method:  Cross-sectional study by postal questionnaire. Sleep disturbances were assessed using the Sleep Disturbance Scale for Children (validated on 1157 healthy children). A total sleep score and six sleep disturbance factors representing the most common sleep disorders were computed. Potential associations between pathological scores and personal, medical and environmental factors were assessed. Results:  Sixteen of 63 boys (25.4%) had a pathological total sleep score compared with 3% in the general population. The most prevalent sleep disorders were disorders of initiating and maintaining sleep (DIMS) 29.7%, sleep-related breathing disorders 15.6% and sleep hyperhydrosis 14.3%. On multivariate analysis, pathological total sleep scores were associated with the need to be moved by a carer (OR = 9.4; 95%CI: 2.2-40.7; p = 0.003) and being the child of a single-parent family (OR = 7.2; 95%CI: 1.5-35.1; p = 0.015) and DIMS with the need to be moved by a carer (OR = 18.0; 95%CI: 2.9-110.6; p = 0.002), steroid treatment (OR = 7.7; 95%CI: 1.4-44.0; p = 0.021) and being the child of a single-parent family (OR = 7.0; 95%CI: 1.3-38.4; p = 0.025). Conclusion:  Sleep disturbances are frequent in boys with DMD and are strongly associated with immobility. Sleep should be systematically assessed in DMD to implement appropriate interventions.

Fuerza de blanco de anchoveta (Engraulis Ringens) utilizando frecuencias de 38 y 120 kHz

Se realizaron experimentos con peces vivos a fin de determinar el valor de la Fuerza de Blanco de anchoveta (Engraulis ringens) utilizando frecuencias de 38 y 120 kHz en la Bahía Paraíso (11°12 'S) a bordo del BIC Humboldt entre los días 01 y 07 de noviembre de 1997. Se colectaron especímenes vivos utilizando dos lanchas de apoyo a bordo de las cuales se mantuvo viva la muestra, empleando tanques de fibra de vidrio con circulación de agua de mar. Las muestras fueron trasladadas al vivero principal ubicado amarrado al BIC Humboldt para aclimatar los especimenes por 24 horas. Luego, se iniciaron las series de experimentos de otras 24 horas (dos para 38 kHz y dos para 120 kHz) consistentes en la medición de la ecointegración total de la jaula versus el interior de la misma. Los resultados fueron obtenidos utilizando hoja de cálculo.

Resultados preliminares de las mediciones de fuerza de blanco in situ de las principales especies pelágicas. Crucero BIC Humboldt 9803-05 de Tumbes a Tacna

Se han utilizado los resultados de 144 lances ejecutados en el transcurso del Crucero 9803-05. Se compararon los histogramas de TS y los de tallas en búsqueda de correlación entre ambas a fin de determinar el factor b20 de la Ecuación de Fuerza de Blanco (20 log (LT,cm) + b20). Se han determinado nuevas ecuaciones de TS para anchoveta (38 y 120 kHz), sardina (120 kHz), jurel (38 kHz) y caballa (38 y 120 kHz). Se deberá continuar con estas mediciones puesto que un cambio en las propuestas reflectivas de los peces puede afectar la correcta obtención de los estimados de biomasa.

The TREAT-NMD DMD Global Database: Analysis of More than 7,000 Duchenne Muscular Dystrophy Mutations.

Analyzing the type and frequency of patient-specific mutations that give rise to Duchenne muscular dystrophy (DMD) is an invaluable tool for diagnostics, basic scientific research, trial planning, and improved clinical care. Locus-specific databases allow for the collection, organization, storage, and analysis of genetic variants of disease. Here, we describe the development and analysis of the TREAT-NMD DMD Global database (http://umd.be/TREAT_DMD/). We analyzed genetic data for 7,149 DMD mutations held within the database. A total of 5,682 large mutations were observed (80% of total mutations), of which 4,894 (86%) were deletions (1 exon or larger) and 784 (14%) were duplications (1 exon or larger). There were 1,445 small mutations (smaller than 1 exon, 20% of all mutations), of which 358 (25%) were small deletions and 132 (9%) small insertions and 199 (14%) affected the splice sites. Point mutations totalled 756 (52% of small mutations) with 726 (50%) nonsense mutations and 30 (2%) missense mutations. Finally, 22 (0.3%) mid-intronic mutations were observed. In addition, mutations were identified within the database that would potentially benefit from novel genetic therapies for DMD including stop codon read-through therapies (10% of total mutations) and exon skipping therapy (80% of deletions and 55% of total mutations).

The effect of a segmental, localized lower limb cooling protocol on muscular strength and balance

The human neuromuscular system is susceptible to changes within the thermal environment. Cold extrinsic temperatures can significantly reduce muscle and nervous system function and communication, which can have consequences for motor performance. A repeated measures design protocol exposed participants to a 12°C cold water immersion (CWI) up to the ankle, knee, and hip to determine the effect that reduced skin and muscle temperature had on balance and strength task execution. Although a linear reduction in the ability to perform balance tasks was seen from the control condition through to the hip CWI, results from the study indicated a significant reduction in dynamic balance (Star Excursion Balance Test reach distance) performance from only the hip CWI (P<0.05). This reduced performance could have been due to an increase in joint stiffness, increased agonist-antagonist co-contraction, and/or reduced isokinetic muscular strength. Reduced physical performance due to cold temperature could negatively impact outdoor recreational athletics.

Neuromotor Mechanisms Involved in the Recovery from Local Muscular Fatigue

The phenomenon of over-recovery consists of a participant’s maximal force levels returning to values above initial levels. The present study examined the presence and causes of over-recovery following local muscular fatigue. Fourteen males completed two fatigue protocols consisting of maximal isometric dorsiflexion contractions. Upon completion of the fatigue protocol participants’ force was monitored over a 15 minute recovery period. Dorsiflexion force and surface electromyography (sEMG) from the tibialis anterior and soleus were monitored concurrently. Following the two fatigue conditions (10 and 20% force decrement) force recovered to 100.5 and 99.5% of initial levels for each condition, respectively. Surface EMG root-mean-square amplitude and MPF exhibited changes consistent with a warm-up effect. It was concluded that over-recovery was not present in the tibialis anterior following a local muscular fatigue. However, the return in force to initial values, rather than a persistent decrement as normally observed, was mediated by the warm-up effect.

Do Neuro-Muscular Adaptations Occur in Endurance-Trained Boys and Men?

Most research on the effects of endurance training has focused on endurance training's health-related benefits and metabolic effects in both children and adults. The purpose of this study was to examine the neuromuscular effects of endurance training and to investigate whether they differ in children (9.0-12.9 years) and adults (18.4-35.6 years). Maximal isometric torque, rate of torque development (RTD), rate of muscle activation (Q30), electromechanical delay (EMD), and time to peak torque and peak RTD were determined by isokinetic dynamometry and surface electromyography (EMG) in elbow and knee flexion and extension. The subjects were 12 endurance-trained and 16 untrained boys, and 15 endurance-trained and 20 untrained men. The adults displayed consistently higher peak torque, RTD, and Q30, in both absolute and normalized values, whereas the boys had longer EMD (64.7+/-17.1 vs. 56.6+/-15.4 ms) and time to peak RTD (98.5+/-32.1 vs. 80.4+/-15.0 ms for boys and men, respectively). Q30, normalized for peak EMG amplitude, was the only observed training effect (1.95+/-1.16 vs. 1.10+/-0.67 ms for trained and untrained men, respectively). This effect could not be shown in the boys. The findings show normalized muscle strength and rate of activation to be lower in children compared with adults, regardless of training status. Because the observed higher Q30 values were not matched by corresponding higher performance measures in the trained men, the functional and discriminatory significance of Q30 remains unclear. Endurance training does not appear to affect muscle strength or rate of force development in either men or boys.

The Role of Membrane Lipid Composition on Skeletal Muscle Damage in the Rodent Model of Duchenne Muscular Dystrophy

Duchenne muscular dystrophy is a X-linked muscle disease, which leads to alterations in membrane phospholipid fatty acid (FA) composition and skeletal muscle damage. Increased membrane saturated FA in muscular dystrophy may suggest its association with increased susceptibility (as being the cause or consequence) to muscle damage. It was hypothesised that increased saturation is positively correlated to increased muscle damage. Correlations were hypothesized to be greater in extensor digitorum longus (EDL) at 20 weeks compared to soleus (SOL) at 10 weeks in dystrophin deficient (mdx) mice. Increased saturation was correlated to damage in EDL at both 10 and 20 weeks, with stronger correlations at 10 weeks. The results suggest that membrane PL FA composition may be associated with damage through two possible means. Increased saturation may be a cause or consequence of membrane damage. Association of membrane composition with eccentric induced damage has underscored the importance of saturated PL FA compositions in damage to dystrophic myofibres.

Ejercicio de resistencia muscular en adultos con diabetes mellitus tipo 2

Tesis (Maestría en Ciencias de Enfermería con Énfasis en Salud Comunitaria) UANL

Evolución del empleo en la industria maquiladora de exportación un estudio de la fuerza de trabajo masculina y femenina en la frontera norte de México [por] Minerva Evangelina Ramos Valdés

Tesis (Maestría en Economía con Especialidad en Economía Industrial) U.A.N.L.

Análisis microestructural de cerámicos utilizando microscopía de fuerza atómica [por] Enrique Manuel López Cuéllar

Tesis (Maestro en Ciencias de la Ingeniería Mecánica con Especialidad en Materiales) U.A.N.L.

Caracterización de precipitados en la aleación de aluminio 6061 por medio de microscopía de fuerza atómica por Maribel de la Garza Garza

Tesis (Maestría en Ciencias de la Ingeniería con Especialidad en Materiales) - U.A.N.L, 1999

Biomecánica muscular del masetero y temporal en pacientes clase II esquelética, dolicofaciales con cambio quirúrgico de plano oclusal por Iraís Lisseth Ojeda Herrera

Tesis (Maestría en Ciencias Odontológicas con Especialidad en Ortodoncia) U.A.N.L.