The Experts below are selected from a list of 2373 Experts worldwide ranked by ideXlab platform
Shraddha Srivastava - One of the best experts on this subject based on the ideXlab platform.
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mediolateral Footpath stabilization during walking in people following stroke
PLOS ONE, 2018Co-Authors: Peichu Kao, Shraddha SrivastavaAbstract:Community dwelling stroke survivors most often fall while walking. Understanding how post-stroke individuals control mediolateral Footpath during walking may help elucidate the mechanisms that contribute to walking instability. By applying the Uncontrolled Manifold (UCM) approach, we investigated (1) how post-stroke individuals coordinate lower-extremity joint motions to stabilize mediolateral Footpath of the swing leg, and (2) how the inter-joint coordination in Footpath stabilization correlates to their walking stability. Nine stroke subjects and nine healthy controls walked on a treadmill at four different speeds. UCM analysis partitions the variance of kinematic configurations across gait cycles into “good variance” (i.e., the variance component leading to a consistent Footpath) or “bad variance” (i.e., the variance component leading to an inconsistent Footpath). We found that both groups had a significantly greater “good” than “bad” variance (p<0.05) for most of the swing phase, suggesting that mediolateral Footpath is an important variable stabilized by the central nervous system during walking. Stroke subjects had significantly greater relative variance difference (ΔV) (i.e. normalized difference between “good” and “bad” variance) (p<0.05), indicating a stronger kinematic synergy in Footpath stabilization, than the controls. In addition, the kinematic synergy in mediolateral Footpath stabilization is strongest during mid-swing but weakest during late swing in healthy gait. However, this phase-dependent strategy is preserved for mid-swing but not for late swing in stroke gait. Moreover, stroke and healthy subjects demonstrated different relationships between UCM and walking stability measures. A stronger kinematic synergy in healthy gait is associated with better walking stability whereas having more “good variance” or stronger kinematic synergy in stroke gait is associated with less walking stability. The current findings suggest that walking with too much “good variance” in people following stroke, despite no effect on the Footpath, may adversely affect their walking stability to some extent.
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coordination of muscles to control the Footpath during over ground walking in neurologically intact individuals and stroke survivors
Experimental Brain Research, 2016Co-Authors: Shraddha Srivastava, Peichu Kao, Darcy S Reisma, Jill S Higginso, Joh P ScholzAbstract:The central nervous system (CNS) is believed to use the abundant degrees of freedom of muscles and joints to stabilize a particular task variable important for task success, such as Footpath during walking. Stroke survivors often demonstrate impaired balance and high incidences of falls due to increased Footpath variability during walking. In the current study, we use the uncontrolled manifold (UCM) approach to investigate the role of motor abundance in stabilizing Footpath during swing phase in healthy individuals and stroke survivors. Twelve stroke survivors and their age- and gender-matched controls walked over-ground at self-selected speed, while electromyographic and kinematic data were collected. UCM analysis partitioned the variance of muscle groups (modes) across gait cycles into “good variance” (i.e., muscle mode variance leading to a consistent or stable Footpath) or “bad variance” (i.e., muscle mode variance resulting in an inconsistent Footpath). Both groups had a significantly greater “good” than “bad” variance, suggesting that Footpath is an important task variable stabilized by the CNS during walking. The relative variance difference that reflects normalized difference between “good” and “bad” variance was not significantly different between groups. However, significant differences in muscle mode structure and muscle mode activation timing were observed between the two groups. Our results suggest that though the mode structure and activation timing are altered, stroke survivors may retain their ability to explore the redundancy within the neuromotor system and utilize it to stabilize the Footpath.
Suksun Horpibulsuk - One of the best experts on this subject based on the ideXlab platform.
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strength evaluation of utilizing recycled plastic waste and recycled crushed glass in concrete Footpaths
Construction and Building Materials, 2019Co-Authors: Yat Choy Wong, Suksun Horpibulsuk, Alireza Mohammadinia, Arul ArulrajahAbstract:Abstract The increasing rate of waste generation and the consequent environmental penalties of landfilling waste glass and waste plastic need global attention to pursue innovative sustainable industrial applications that can divert these wastes from landfills for useful construction activities. This study entails incorporating recycled plastic waste (RPW) and recycled crushed glass (RCG) as coarse aggregate replacement in concrete mixture and to evaluate its feasibility as concrete Footpath construction. The coarse aggregates in concrete were replaced by RPW and RCG aggregates in proportions of 0%, 10%, 20%, 30%, 40%, and 50% was investigated. The properties of concrete evaluated in this study include uniaxial strength, tensile strength and capillary water uptake. Results from this investigation showed that incorporation of RPW and RCG in concrete can be a viable solution for the recycling of plastic waste and crushed glass in industrial applications. Although, the compressive and splitting tensile strength values of the concrete samples containing RPW and RCG aggregate were found to be reduced due to low adhesion between the recycled aggregates and the cement gel matrix as well as low aggregate crushing resistance, coarse aggregate replacement were found to be still viable up to 20% by volume for RPW and up to 30% by volume for RCG for use in Footpath construction.
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recycled concrete aggregate municipal glass blends as a low carbon resource material for Footpaths
Road Materials and Pavement Design, 2018Co-Authors: Arul Arulrajah, Yanjun Du, Monzur Alam Imteaz, Suksun Horpibulsuk, Jack Shuilong ShenAbstract:Construction and Demolition (C&D) materials comprising recycled concrete aggregate (RCA), fine recycled glass (FRG) and a blend comprising 85% RCA with 15% FRG (85RCA/15FRG) were evaluated for thei...
Alireza Mohammadinia - One of the best experts on this subject based on the ideXlab platform.
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strength evaluation of utilizing recycled plastic waste and recycled crushed glass in concrete Footpaths
Construction and Building Materials, 2019Co-Authors: Yat Choy Wong, Suksun Horpibulsuk, Alireza Mohammadinia, Arul ArulrajahAbstract:Abstract The increasing rate of waste generation and the consequent environmental penalties of landfilling waste glass and waste plastic need global attention to pursue innovative sustainable industrial applications that can divert these wastes from landfills for useful construction activities. This study entails incorporating recycled plastic waste (RPW) and recycled crushed glass (RCG) as coarse aggregate replacement in concrete mixture and to evaluate its feasibility as concrete Footpath construction. The coarse aggregates in concrete were replaced by RPW and RCG aggregates in proportions of 0%, 10%, 20%, 30%, 40%, and 50% was investigated. The properties of concrete evaluated in this study include uniaxial strength, tensile strength and capillary water uptake. Results from this investigation showed that incorporation of RPW and RCG in concrete can be a viable solution for the recycling of plastic waste and crushed glass in industrial applications. Although, the compressive and splitting tensile strength values of the concrete samples containing RPW and RCG aggregate were found to be reduced due to low adhesion between the recycled aggregates and the cement gel matrix as well as low aggregate crushing resistance, coarse aggregate replacement were found to be still viable up to 20% by volume for RPW and up to 30% by volume for RCG for use in Footpath construction.
Peichu Kao - One of the best experts on this subject based on the ideXlab platform.
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mediolateral Footpath stabilization during walking in people following stroke
PLOS ONE, 2018Co-Authors: Peichu Kao, Shraddha SrivastavaAbstract:Community dwelling stroke survivors most often fall while walking. Understanding how post-stroke individuals control mediolateral Footpath during walking may help elucidate the mechanisms that contribute to walking instability. By applying the Uncontrolled Manifold (UCM) approach, we investigated (1) how post-stroke individuals coordinate lower-extremity joint motions to stabilize mediolateral Footpath of the swing leg, and (2) how the inter-joint coordination in Footpath stabilization correlates to their walking stability. Nine stroke subjects and nine healthy controls walked on a treadmill at four different speeds. UCM analysis partitions the variance of kinematic configurations across gait cycles into “good variance” (i.e., the variance component leading to a consistent Footpath) or “bad variance” (i.e., the variance component leading to an inconsistent Footpath). We found that both groups had a significantly greater “good” than “bad” variance (p<0.05) for most of the swing phase, suggesting that mediolateral Footpath is an important variable stabilized by the central nervous system during walking. Stroke subjects had significantly greater relative variance difference (ΔV) (i.e. normalized difference between “good” and “bad” variance) (p<0.05), indicating a stronger kinematic synergy in Footpath stabilization, than the controls. In addition, the kinematic synergy in mediolateral Footpath stabilization is strongest during mid-swing but weakest during late swing in healthy gait. However, this phase-dependent strategy is preserved for mid-swing but not for late swing in stroke gait. Moreover, stroke and healthy subjects demonstrated different relationships between UCM and walking stability measures. A stronger kinematic synergy in healthy gait is associated with better walking stability whereas having more “good variance” or stronger kinematic synergy in stroke gait is associated with less walking stability. The current findings suggest that walking with too much “good variance” in people following stroke, despite no effect on the Footpath, may adversely affect their walking stability to some extent.
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coordination of muscles to control the Footpath during over ground walking in neurologically intact individuals and stroke survivors
Experimental Brain Research, 2016Co-Authors: Shraddha Srivastava, Peichu Kao, Darcy S Reisma, Jill S Higginso, Joh P ScholzAbstract:The central nervous system (CNS) is believed to use the abundant degrees of freedom of muscles and joints to stabilize a particular task variable important for task success, such as Footpath during walking. Stroke survivors often demonstrate impaired balance and high incidences of falls due to increased Footpath variability during walking. In the current study, we use the uncontrolled manifold (UCM) approach to investigate the role of motor abundance in stabilizing Footpath during swing phase in healthy individuals and stroke survivors. Twelve stroke survivors and their age- and gender-matched controls walked over-ground at self-selected speed, while electromyographic and kinematic data were collected. UCM analysis partitioned the variance of muscle groups (modes) across gait cycles into “good variance” (i.e., muscle mode variance leading to a consistent or stable Footpath) or “bad variance” (i.e., muscle mode variance resulting in an inconsistent Footpath). Both groups had a significantly greater “good” than “bad” variance, suggesting that Footpath is an important task variable stabilized by the CNS during walking. The relative variance difference that reflects normalized difference between “good” and “bad” variance was not significantly different between groups. However, significant differences in muscle mode structure and muscle mode activation timing were observed between the two groups. Our results suggest that though the mode structure and activation timing are altered, stroke survivors may retain their ability to explore the redundancy within the neuromotor system and utilize it to stabilize the Footpath.
Mark A Tully - One of the best experts on this subject based on the ideXlab platform.
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a comparison of road and Footpath based walkability indices and their associations with active travel
Journal of transport and health, 2017Co-Authors: Sharo Cruise, Ruth F Hunte, Frank Kee, Mick Donnelly, Gerai Ellis, Mark A TullyAbstract:Abstract Background Many studies have used the concept of ‘walkability’ to assess how conducive a neighbourhood is to physical activity, especially active travel. Studies in the United States and Australia have traditionally used a road-based network system of intersection density to derive a walkability index. However, other studies suggest that analyses based on Footpath networks may provide a more robust basis for assessing the walkability of built environments in the European context as they better capture alternative opportunities for physical activity such as parks and greenways. To date, no studies have examined whether a road- or Footpath-based network is more closely related to actual physical activity behaviour. Therefore, the aims of this paper were to examine associations between active travel and walkability indices based on both road- and Footpath-based intersection density and to establish which measure provided the best fit to the data. Methods Cross-sectional survey and geographical information system (GIS) data were collected from February 2010-January 2011. A series of crude and fully adjusted zero-inflated negative binomial regression analyses examined associations between road- and Footpath-based walkability and the average minutes per week of active travel. Results Model fit indices suggested that the models using road-based walkability provided a marginally better fit. However, regression results indicated similar findings with respect to the effect of road- and Footpath-based walkability on active travel. Conclusion Results suggest that Footpath-based indices of walkability are comparable to road-based indices in their associations with active travel and are an alternative model, particularly for assessing environmental change in non-road-based built environment interventions.
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connectivity and physical activity using Footpath networks to measure the walkability of built environments
Environment and Planning B-planning & Design, 2016Co-Authors: Gerai Ellis, Ruth F Hunte, Mark A Tully, Michael Donnelly, Luke Kellehe, Frank KeeAbstract:There is now a strong body of research that suggests that the form of the built environment can influence levels of physical activity, leading to an increasing interest in incorporating health objectives into spatial planning and regeneration. There have been a number of strands to this research, one of which has sought to develop objective measurements of the built environment using geographic information systems involving measures of connectivity and proximity to compare the relative ‘walkability’of different neighbourhoods. The development of the ‘walkability index’ has become a popular indicator of the spatial distribution of those built environment features that are considered to have the greatest positive influence on levels of physical activity. The success of this measure is built on its ability to capture succinctly correlates of physical activity using routinely available spatial data, which includes using road centre lines to measure connectivity. In this paper we discuss two key aspects of the walkability index. First, as suggested by others, that the use of a Footpath network, rather than road centre lines, may be far more effective in evaluating walkability. This may be particularly important for assessing changes in walkability arising from pedestrian-focused infrastructure projects, such as greenways. Second, we explore the implications of this for how connectivity can be measured. We take six different measures of connectivity and first analyse the relationships between them and then test their correlation with actual levels of physical activity of local residents in Belfast, Northern Ireland. We find that the best measurements appear to be intersection density and metric reach and use this finding to discuss the implications for developing tools that may better support decision-making in spatial planning.