Search results for "FLEX"
showing 10 items of 1677 documents
Neural Activation During Submaximal Contractions Seems More Reflective of Neuromuscular Ageing than Maximal Voluntary Activation
2016
International audience; This study aimed at testing the hypothesis that differences in neural activation strategy during submaximal but not maximal plantarflexions exist between young and older men. Eleven young men (YM, 26 +/- 4 years) and thirteen old men (OM, 76 +/- 3 years) volunteered for the investigation. Maximal voluntary torque (MVT) was 38.2%, lower (p < 0.001) in OM than in YM, while voluntary activation was equivalent (similar to 97%). The relationship between the interpolated twitch torque and the voluntary torque (IT-VT relationship) was composite (curvilinear + exponential) for both age-groups. However, the OM showed accentuated concavity, as attested by the occurrence of the…
A simplified framework to optimize MRI contrast preparation
2018
PURPOSE This article proposes a rigorous optimal control framework for the design of preparation schemes that optimize MRI contrast based on relaxation time differences. METHODS Compared to previous optimal contrast preparation schemes, a drastic reduction of the optimization parameter number is performed. The preparation scheme is defined as a combination of several block pulses whose flip angles, phase terms and inter-pulse delays are optimized to control the magnetization evolution. RESULTS The proposed approach reduces the computation time of B 0 -robust preparation schemes to around a minute (whereas several hours were required with previous schemes), with negligible performance loss. …
The involvement of ankle muscles in maintaining balance in the upright posture is higher in elderly fallers
2016
International audience; The purpose of this study was to determine whether the mechanical contribution of ankle muscles in the upright stance differed among young adults (YA) (n = 10, age: similar to 24.3), elderly non-fallers (ENF) (n = 12, age: similar to 77.3) and elderly fallers (EF) (n = 20, age: similar to 80.7). Torque and electromyographic (EMG) activity were recorded on the triceps surae and tibialis anterior during maximum and submaximum contractions in the seated position. EMG activity was also recorded in subjects standing still. Plantar flexor (PF) and dorsal flexor (DF) torques generated in the upright posture were estimated from the torque-EMG relationship obtained during sub…
Seasonal changes in host phenotype manipulation by an acanthocephalan: time to be transmitted?
2009
Parasitology, 136 (2)
Data from: Effects of undergrowth removal and edge proximity on ground beetles and vascular plants in urban boreal forests
2019
Urban forests are regularly managed for human safety and aesthetic reasons, but they are crucial habitat for many species. Removals of undergrowth occur commonly in these forests, yet the ecological consequences of these operations are poorly understood. We sampled ground beetles (Coleoptera, Carabidae) and vascular plants along 20-m edge gradients in Finnish urban forests, in five stands treated 0.5−2.5 years earlier with undergrowth removal and in five untreated stands. We hypothesized that undergrowth removal and edge proximity would benefit opportunistic and open-habitat species, whereas shady-habitat species would be affected negatively. (1) Regarding carabids, diversity and evenness i…
The performance of thin-film Li-ion batteries under flexural deflection
2006
A method is introduced to study the effects of flexural deformation on the electrical performance of thin-film lithium-ion batteries. Flexural deformation of thin films is of interest to engineers for applications that can be effective in conformal spaces in conjunction with multi-functional composite laminates in structural members under mechanical deflections such as thin airfoils used in unmanned aerial vehicles (UAVs). A test fixture was designed and built using rapid prototyping techniques. A baseline reference charge/discharge cycle was initially obtained with the device in its un-flexed state, in order to later contrast the performance of the thin-film battery when subjected to defle…
Effects of power resistance training program with elastic bands on body composition, muscle strength and physical function in older women
2020
The aim of this study was to investigate the effects of a power-strength resistance program with elastic bands on body composition, physical function, and muscle strength in older women. For such purpose, a randomized controlled trial with a pre-post-intervention design was conducted. Thus, 58 healthy, physically independent, sedentary women, aged 65-85 years, were randomly allocated to the intervention (n = 28) or control group (n = 30). Measurements of body composition (total mass, total fat mass, total skeletal-muscle mass, and body fat percentage), isokinetic muscle strength of knee flexors and extensors (at 60º/second and 180º/second), and physical performance (flexibility, agility/dyn…
Isolated, Subtle Neurological Abnormalities in Mild Cognitive Impairment Types.
2019
Isolated, subtle neurological abnormalities (ISNA) are commonly seen in aging and have been related to cerebral small vessel disease (SVD) and subcortical atrophy in neurologically and cognitively healthy aging subjects.To investigate the frequency of ISNA in different mild cognitive impairment (MCI) types and to evaluate for each MCI type, the cross-sectional relation between ISNA and white matter hyperintensities (WMH), lacunes, caudate atrophy, and ventricular enlargement.One thousand two hundred fifty subjects with different MCI types were included in the analysis and underwent brain magnetic resonance imaging. WMHs were assessed through two visual rating scales. Lacunes were also rated…
Strength of pre-Roman amphorae: Comparison of the different types
2015
Abstract Given that amphorae were used for storage or for long and/or short distance transport, they must have been able to retain their content and, at the same time, be able to resist important load during transport. This paper concerns aspects of the techno-functionality of pre-Roman Iberian amphorae. The basic performance requirement concerned here is the mechanical strength (transverse rupture strength: TRS). Strength is related to the adequacy for storage or short and/or long distance transport that, up to now, is only assessed by typological identification or archaeological evidence. Experimental implementation on actual archaeological material has confirmed that strength increased w…
Energy management of multi-carrier smart buildings for integrating local renewable energy systems
2016
The proposed paper aims at defining a Building Management System (BMS) able to control energy flows inside a smart building integrated with various energy networks and Renewable Energy Resources (RES). The smart building envisaged in this work interacts with different energy carriers and is equipped with cogeneration and RES systems, as well as storage devices, which enable a certain degree of flexibility in the energy usage. The smart building is modelled as a multi-carrier hub, by defining the graphical and mathematical model of the building system. Moreover, the control criteria of the BMS are explained and the implementation of the BMS itself is depicted, along with some early results. …