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CONTEXT: Sensorimotor training is commonly used in a rehabilitative setting; however, the effectiveness of an unexpected disturbance program (UDP) to enhance performance measures in uninjured elite athletes is unknown. OBJECTIVE: To assess the impact of a 3-wk UDP program on strength, power, and proprioceptive measures. DESIGN: Matched-group, pre-post design. SETTING: National sport institute. PARTICIPANTS: 21 international-level female field hockey athletes. INTERVENTION: Two 45-min UDP sessions were incorporated into each week of a 3-wk training program (total 6 sessions). MAIN OUTCOME MEASURES: 1-repetition-maximum strength, lower-limb power, 20-m running speed, and proprioception tests were performed before and after the experimental period. RESULTS: Substantial improvements in running sprint speed at 5-m (4.4 ± 2.6%; effect size [ES]: 0.88), 10-m (2.1 ± 1.9%; ES: 0.51), and 20-m (1.0 ± 1.6%; ES: 0.23) were observed in the UDP group. Squat-jump performance was also clearly enhanced when compared to the control group (3.1 ± 6.1%; ES: 0.23). Small but clear improvements in maximal strength were observed in both groups. CONCLUSIONS: A 3-wk UDP can elicit clear enhancements in running sprint speed and concentric-only jump performance. These improvements are suggestive of enhanced explosive strength and are particularly notable given the elite training status of the cohort and relatively short duration of the intervention. Thus, the authors would reiterate the statement by Gruber et al (2004) that sensorimotor training is a "highly efficient" modality for improving explosive strength.
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Rendimiento Atlético , Hockey , Acondicionamiento Físico Humano/métodos , Adulto , Atletas , Prueba de Esfuerzo , Femenino , Humanos , Adulto JovenRESUMEN
CONTEXT: The Unexpected-Disturbance Program (UDP) promotes exercises in response to so-called involuntary short- to midlatency disturbances. OBJECTIVE: This study investigated the effectiveness of the UDP in the last 6 wk of rehabilitation. DESIGN: Pre-post study with 2-tailed paired t tests for limited a priori comparisons to examine differences. SETTING: National Sports Institute of Malaysia. PARTICIPANTS: 24 Malaysian national athletes. INTERVENTIONS: 7 sessions/wk of 90 min with 3 sessions allocated for 5 or 6 UDP exercises. MAIN OUTCOMES: Significant improvements for men and women were noted. Tests included 20-m sprint, 1-repetition-maximum single-leg press, standing long jump, single-leg sway, and a psychological questionnaire. RESULTS: For men and women, respectively, average strength improvements of 22% (d = 0.96) and 29% (d = 1.05), sprint time of 3% (d = 1.06) and 4% (d = 0.58), and distance jumped of 4% (d = 0.59) and 6% (d = 0.47) were noted. In addition, athletes reported improved perceived confidence in their abilities. All athletes improved in each functional test except for long jump in 2 of the athletes. Mediolateral sway decreased in 18 of the 22 athletes for the injured limb. CONCLUSION: The prevention training with UDP resulted in improved conditioning and seems to decrease mediolateral sway.
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Lesiones del Ligamento Cruzado Anterior/rehabilitación , Reconstrucción del Ligamento Cruzado Anterior/rehabilitación , Traumatismos en Atletas/rehabilitación , Terapia por Ejercicio/métodos , Adulto , Lesiones del Ligamento Cruzado Anterior/cirugía , Traumatismos en Atletas/cirugía , Rendimiento Atlético/fisiología , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Fuerza Muscular/fisiología , Equilibrio Postural/fisiología , Carrera/fisiología , Resultado del Tratamiento , Adulto JovenRESUMEN
A number of three LC-MS/MS hybrid systems (QTof, TripleTof and QTrap) has been used to profile small metabolites (m/z 100-1000) and to detect the targeted metabolites such as quassinoids, alkaloids, triterpene and biphenylneolignans from the aqueous extracts of Eurycoma longifolia. The metabolite profiles of small molecules showed four significant clusters in the principle component analysis for the aqueous extracts of E. longifolia, which had been collected from different geographical terrains (Perak and Pahang) and processed at different extraction temperatures (35°C and 100°C). A small peptide of leucine (m/z 679) and a new hydroxyl methyl ß-carboline propionic acid have been identified to differentiate E. longifolia extracts that prepared at 35°C and 100°C, respectively. From the targeted metabolites identification, it was found that 3,4É-dihydroeurycomanone (quassinoids) and eurylene (squalene-type triterpene) could only be detected in the Pahang extract, whereas canthin-6-one-3N-oxide could only be detected in the Perak extract. Overall, quassinoids were present in the highest concentration, particularly eurycomanone and its derivatives compared to the other groups of metabolites. However, the concentration of canthin-6-one and ß-carboline alkaloids was significantly increased when the roots of the plant samples were extracted at 100°C.
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Alcaloides/análisis , Cromatografía Liquida/métodos , Eurycoma/química , Lignanos/análisis , Espectrometría de Masas en Tándem/métodos , Triterpenos/análisis , Alcaloides/química , Eurycoma/metabolismo , Calor , Lignanos/química , Malasia , Extractos Vegetales/química , Raíces de Plantas/química , Análisis de Componente Principal , Triterpenos/químicaRESUMEN
The global sustainable bioenergy (GSB) project was formed in 2009 with the goal of providing guidance with respect to the feasibility and desirability of sustainable, bioenergy-intensive futures. Stage 1 of this project held conventions with a largely common format on each of the world's continents, was completed in 2010, and is described in this paper. Attended by over 400 persons, the five continental conventions featured presentations, breakout sessions, and drafting of resolutions that were unanimously passed by attendees. The resolutions highlight the potential of bioenergy to make a large energy supply contribution while honouring other priorities, acknowledge the breadth and complexity of bioenergy applications as well as the need to take a systemic approach, and attest to substantial intra- and inter-continental diversity with respect to needs, opportunities, constraints and current practice relevant to bioenergy. The following interim recommendations based on stage 1 GSB activities are offered: - Realize that it may be more productive, and also more correct, to view the seemingly divergent assessments of bioenergy as answers to two different questions rather than the same question. Viewed in this light, there is considerably more scope for reconciliation than might first be apparent, and it is possible to be informed rather than paralysed by divergent assessments.- Develop established and advanced bioenergy technologies such that each contributes to the other's success. That is, support and deploy in the near-term meritorious, established technologies in ways that enhance rather than impede deployment of advanced technologies, and support and deploy advanced technologies in ways that expand rather than contract opportunities for early adopters and investors.- Be clear in formulating policies what mix of objectives are being targeted, measure the results of these policies against these objectives and beware of unintended consequences.- Undertake further exploration of land efficiency levers and visions for multiply-beneficial bioenergy deployment. This should be unconstrained by current practices, since we cannot hope to achieve a sustainable and a secure future by continuing the practices that have led to the unsustainable and insecure present. It should also be approached from a global perspective, based on the best science available, and consider the diverse realities, constraints, needs and opportunities extant in different regions of the world.The future trajectory of the GSB project is also briefly considered.
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Both total phenolic content (TPC) and total flavonoid content (TFC) of Labisia pumila extracts were determined spectrophotometrically. L. pumila leaves extracted in 60% methanol (MeOH) were fractionated on C18 cartridge and the antioxidant property of each fraction was determined by measuring free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity. The 40% MeOH fraction exhibited the highest scavenging activity. Nine flavonols (quercetin, myricetin and kaempferol), two flavanols (catechin and epigallocatechin) and nine phenolic acids were identified from this active fraction by UPLC-ESI-MS/MS, and confirmed by comparison with the mass spectra of standard aglycones, theoretical fragments generated from MS Fragmenter software, and literature values.
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A mathematical model to describe the oscillatory bursting activity of pancreatic beta-cells is combined with a model of glucose regulation system in this work to study the bursting pattern under regulated extracellular glucose stimulation. The bursting electrical activity in beta-cells is crucial for the release of insulin, which acts to regulate the blood glucose level. Different types of bursting pattern have been observed experimentally in glucose-stimulated islets both in vivo and in vitro, and the variations in these patterns have been linked to changes in glucose level. The combined model in this study enables us to have a deeper understanding on the regime change of bursting pattern when glucose level changes due to hormonal regulation, especially in the postprandial state. This is especially important as the oscillatory components of electrical activity play significant physiological roles in insulin secretion and some components have been found to be lost in type 2 diabetic patients.
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Glucosa/farmacología , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Modelos Biológicos , Animales , Glucemia/análisis , Espacio Extracelular/efectos de los fármacos , Espacio Extracelular/metabolismo , Glucoquinasa/metabolismoRESUMEN
A model of glucose regulation system was combined with a model of insulin-signaling pathways in this study. A feedback loop was added to link the transportation of glucose into cells (by GLUT4 in the insulin-signaling pathways) and the insulin-dependent glucose uptake in the glucose regulation model using the Michaelis-Menten kinetic model. A value of K(m) for GLUT4 was estimated using Genetic Algorithm. The estimated value was found to be 25.3 mM, which was in the range of K(m) values found experimentally from in vivo and in vitro human studies. Based on the results of this study, the combined model enables us to understand the overall dynamics of glucose at the systemic level, monitor the time profile of components in the insulin-signaling pathways at the cellular level and gives a good estimate of the K(m) value of glucose transportation by GLUT4. In conclusion, metabolic modeling such as displayed in this study provides a good predictive method to study the step-by-step reactions in an organism at different levels and should be used in combination with experimental approach to increase our understanding of metabolic disorders such as type 2 diabetes.