The Experts below are selected from a list of 22092 Experts worldwide ranked by ideXlab platform
Hiroshi Ando - One of the best experts on this subject based on the ideXlab platform.
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The Harmonic Ratio of trunk acceleRation predicts falling among older people: results of a 1-year prospective study
Journal of NeuroEngineering and Rehabilitation, 2013Co-Authors: Soichiro Hirata, Kota Tsutsumimoto, Shogo Misu, Hiroshi AndoAbstract:Background Gait variables derived from trunk accelerometry may predict the risk of falls; however, their associations with falls are not fully understood. The purpose of the study was to determine which gait variables derived from upper and lower trunk accelerometry are associated with the incidence of falls, and to compare the discriminative ability of gait variables and physical performance. Methods This study was a 1-year prospective study. Older people ( n = 73) walked normally while wearing accelerometers attached to the upper and lower trunk. Participants were classified as fallers ( n = 16) or non-fallers ( n = 57) based on the incidence of falls over 1 year. The Harmonic Ratio (HR) of the upper and lower trunk was measured. Physical performance was measured in five chair stands and in the timed up and go test. Results The HR of the upper and lower trunk were consistently lower in fallers than non-fallers ( P < 0.05). Upper trunk HR, was independently associated with the incidence of falls ( P < 0.05) after adjusting for confounding factors including physical performances. Consequently, upper trunk HR showed high discrimination for the risk of falls (AUC = 0.81). Conclusions HR derived from upper trunk accelerometry may predict the risk of falls, independently of physical performance. The discriminative ability of HR for the risk of falls may have some validity, and further studies are needed to confirm the clinical relevance of trunk HR.
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the Harmonic Ratio of trunk acceleRation predicts falling among older people results of a 1 year prospective study
Journal of Neuroengineering and Rehabilitation, 2013Co-Authors: Takehiko Doi, Soichiro Hirata, Kota Tsutsumimoto, Shogo Misu, Rei Ono, Hiroshi AndoAbstract:Gait variables derived from trunk accelerometry may predict the risk of falls; however, their associations with falls are not fully understood. The purpose of the study was to determine which gait variables derived from upper and lower trunk accelerometry are associated with the incidence of falls, and to compare the discriminative ability of gait variables and physical performance. This study was a 1-year prospective study. Older people (n = 73) walked normally while wearing accelerometers attached to the upper and lower trunk. Participants were classified as fallers (n = 16) or non-fallers (n = 57) based on the incidence of falls over 1 year. The Harmonic Ratio (HR) of the upper and lower trunk was measured. Physical performance was measured in five chair stands and in the timed up and go test. The HR of the upper and lower trunk were consistently lower in fallers than non-fallers (P < 0.05). Upper trunk HR, was independently associated with the incidence of falls (P < 0.05) after adjusting for confounding factors including physical performances. Consequently, upper trunk HR showed high discrimination for the risk of falls (AUC = 0.81). HR derived from upper trunk accelerometry may predict the risk of falls, independently of physical performance. The discriminative ability of HR for the risk of falls may have some validity, and further studies are needed to confirm the clinical relevance of trunk HR.
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Brain Atrophy and Trunk Stability During Dual-Task Walking Among Older Adults
The journals of gerontology. Series A Biological sciences and medical sciences, 2011Co-Authors: Takehiko Doi, Hiroshi Ando, Hyuma Makizako, Hiroyuki Shimada, Daisuke Yoshida, Kengo Ito, Takashi Kato, Takao SuzukiAbstract:BACKGROUND Dual-task walking is believed to be more cognitively demanding than normal walking and alters trunk movement among older adults. However, the possible association between brain atrophy and spatiotemporal gait parameters, particularly during dual-task walking, is poorly understood. In this study, we examined the relationship between dual-task walking and brain atrophy. METHODS One hundred ten elderly adults (aged 65-94 years, women n = 55) underwent magnetic resonance imaging scanning and gait experiments under normal and dual-task walking conditions. Linear acceleRations of the trunk were measured in vertical, anteroposterior, and mediolateral directions using a triaxial accelerometer attached to the lower trunk. Gait speed, stride length, and cadence were recorded. The Harmonic Ratio, a measure of trunk stability, was computed separately in each direction to evaluate the smoothness of trunk movement during walking. Brain atrophy was quantitatively assessed using magnetic resonance image data. RESULTS Gait speed, stride length, cadence, and Harmonic Ratio in all directions were lower in dual-task walking than in normal walking (p < .05). The dual-task-related changes in Harmonic Ratio were independently correlated with brain atrophy adjusted for subject characteristics only in the vertical direction (p < .05). CONCLUSIONS Our findings support the hypothesis that dual-task walking is more cognitively demanding than normal walking. Decreased trunk stability during dual-task walking is associated with brain atrophy. Additional studies are necessary to elucidate the effects of regional brain atrophy on the control of walking.
Xuejing Sun - One of the best experts on this subject based on the ideXlab platform.
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pitch determination and voice quality analysis using subHarmonic to Harmonic Ratio
International Conference on Acoustics Speech and Signal Processing, 2002Co-Authors: Xuejing SunAbstract:This paper presents an improvement of a previously proposed pitch determination algorithm (PDA). Particularly aiming at handling alternate cycles in speech signal, the algorithm estimates pitch through spectrum shifting on logarithmic frequency scale and calculating the SubHarmonic-to-Harmonic Ratio (SHR). The evaluation results on two databases show that this algorithm performs considerably better than other PDAs compared. Application of SHR to voice quality analysis task is also presented. The implementation and evaluation routines are available from <http://mel.speech.nwu.edu/sunxj/pda.htm>.
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ICASSP - Pitch determination and voice quality analysis using SubHarmonic-to-Harmonic Ratio
IEEE International Conference on Acoustics Speech and Signal Processing, 2002Co-Authors: Xuejing SunAbstract:This paper presents an improvement of a previously proposed pitch determination algorithm (PDA). Particularly aiming at handling alternate cycles in speech signal, the algorithm estimates pitch through spectrum shifting on logarithmic frequency scale and calculating the SubHarmonic-to-Harmonic Ratio (SHR). The evaluation results on two databases show that this algorithm performs considerably better than other PDAs compared. Application of SHR to voice quality analysis task is also presented. The implementation and evaluation routines are available from <http://mel.speech.nwu.edu/sunxj/pda.htm>.
Takehiko Doi - One of the best experts on this subject based on the ideXlab platform.
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Effects of white matter lesions on trunk stability during dual-task walking among older adults with mild cognitive impairment.
Age (Dordrecht Netherlands), 2015Co-Authors: Takehiko Doi, Kota Tsutsumimoto, Hyuma Makizako, Hiroyuki Shimada, Ryo Hotta, Sho Nakakubo, Takao SuzukiAbstract:The linkage between gait and cognition has been shown in cases of white matter lesion (WML) that affect gait in older adults. Dual-task walking is believed to be cognitively demanding and to alter trunk movement, and gait impairment in people with mild cognitive impairment (MCI) is highlighted under this condition. However, the association between dual-task walking and structural changes in the brain, particularly with WML, in people with MCI is still unclear. The aim of this study was to examine the association between trunk stability during dual-task walking and WML in 560 older adults with MCI. We measured magnetic resonance imaging (MRI) and gait variables. Gait variables included Harmonic Ratio in vertical, mediolateral, and anteroposterior directions, analyzed using a tri-axial accelerometer attached to the lower trunk. Walking conditions were normal walking and dual-task walking (counting backwards while walking) conditions. Demographical data and brain atrophy were measured as covariates. Subjects were classified into non-severe WML (n = 451, mean age = 73.2 years) and severe WML (n = 109, mean age = 75.9 years) groups. Linear mixed-effects model analysis controlled for covariates showed dual-task-related changes in all Harmonic Ratios associated with WML (p < 0.05). Even after adjustment for executive function, Harmonic Ratio in the mediolateral direction was significantly associated with WML (p < 0.05). Our findings revealed that WMLs were associated with trunk stability in dual-task walking. Further studies are required to investigate the neural basis for deficits in gait ability among MCI subjects.
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the Harmonic Ratio of trunk acceleRation predicts falling among older people results of a 1 year prospective study
Journal of Neuroengineering and Rehabilitation, 2013Co-Authors: Takehiko Doi, Soichiro Hirata, Kota Tsutsumimoto, Shogo Misu, Rei Ono, Hiroshi AndoAbstract:Gait variables derived from trunk accelerometry may predict the risk of falls; however, their associations with falls are not fully understood. The purpose of the study was to determine which gait variables derived from upper and lower trunk accelerometry are associated with the incidence of falls, and to compare the discriminative ability of gait variables and physical performance. This study was a 1-year prospective study. Older people (n = 73) walked normally while wearing accelerometers attached to the upper and lower trunk. Participants were classified as fallers (n = 16) or non-fallers (n = 57) based on the incidence of falls over 1 year. The Harmonic Ratio (HR) of the upper and lower trunk was measured. Physical performance was measured in five chair stands and in the timed up and go test. The HR of the upper and lower trunk were consistently lower in fallers than non-fallers (P < 0.05). Upper trunk HR, was independently associated with the incidence of falls (P < 0.05) after adjusting for confounding factors including physical performances. Consequently, upper trunk HR showed high discrimination for the risk of falls (AUC = 0.81). HR derived from upper trunk accelerometry may predict the risk of falls, independently of physical performance. The discriminative ability of HR for the risk of falls may have some validity, and further studies are needed to confirm the clinical relevance of trunk HR.
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Brain Atrophy and Trunk Stability During Dual-Task Walking Among Older Adults
The journals of gerontology. Series A Biological sciences and medical sciences, 2011Co-Authors: Takehiko Doi, Hiroshi Ando, Hyuma Makizako, Hiroyuki Shimada, Daisuke Yoshida, Kengo Ito, Takashi Kato, Takao SuzukiAbstract:BACKGROUND Dual-task walking is believed to be more cognitively demanding than normal walking and alters trunk movement among older adults. However, the possible association between brain atrophy and spatiotemporal gait parameters, particularly during dual-task walking, is poorly understood. In this study, we examined the relationship between dual-task walking and brain atrophy. METHODS One hundred ten elderly adults (aged 65-94 years, women n = 55) underwent magnetic resonance imaging scanning and gait experiments under normal and dual-task walking conditions. Linear acceleRations of the trunk were measured in vertical, anteroposterior, and mediolateral directions using a triaxial accelerometer attached to the lower trunk. Gait speed, stride length, and cadence were recorded. The Harmonic Ratio, a measure of trunk stability, was computed separately in each direction to evaluate the smoothness of trunk movement during walking. Brain atrophy was quantitatively assessed using magnetic resonance image data. RESULTS Gait speed, stride length, cadence, and Harmonic Ratio in all directions were lower in dual-task walking than in normal walking (p < .05). The dual-task-related changes in Harmonic Ratio were independently correlated with brain atrophy adjusted for subject characteristics only in the vertical direction (p < .05). CONCLUSIONS Our findings support the hypothesis that dual-task walking is more cognitively demanding than normal walking. Decreased trunk stability during dual-task walking is associated with brain atrophy. Additional studies are necessary to elucidate the effects of regional brain atrophy on the control of walking.
Takao Suzuki - One of the best experts on this subject based on the ideXlab platform.
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Effects of white matter lesions on trunk stability during dual-task walking among older adults with mild cognitive impairment.
Age (Dordrecht Netherlands), 2015Co-Authors: Takehiko Doi, Kota Tsutsumimoto, Hyuma Makizako, Hiroyuki Shimada, Ryo Hotta, Sho Nakakubo, Takao SuzukiAbstract:The linkage between gait and cognition has been shown in cases of white matter lesion (WML) that affect gait in older adults. Dual-task walking is believed to be cognitively demanding and to alter trunk movement, and gait impairment in people with mild cognitive impairment (MCI) is highlighted under this condition. However, the association between dual-task walking and structural changes in the brain, particularly with WML, in people with MCI is still unclear. The aim of this study was to examine the association between trunk stability during dual-task walking and WML in 560 older adults with MCI. We measured magnetic resonance imaging (MRI) and gait variables. Gait variables included Harmonic Ratio in vertical, mediolateral, and anteroposterior directions, analyzed using a tri-axial accelerometer attached to the lower trunk. Walking conditions were normal walking and dual-task walking (counting backwards while walking) conditions. Demographical data and brain atrophy were measured as covariates. Subjects were classified into non-severe WML (n = 451, mean age = 73.2 years) and severe WML (n = 109, mean age = 75.9 years) groups. Linear mixed-effects model analysis controlled for covariates showed dual-task-related changes in all Harmonic Ratios associated with WML (p < 0.05). Even after adjustment for executive function, Harmonic Ratio in the mediolateral direction was significantly associated with WML (p < 0.05). Our findings revealed that WMLs were associated with trunk stability in dual-task walking. Further studies are required to investigate the neural basis for deficits in gait ability among MCI subjects.
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Brain Atrophy and Trunk Stability During Dual-Task Walking Among Older Adults
The journals of gerontology. Series A Biological sciences and medical sciences, 2011Co-Authors: Takehiko Doi, Hiroshi Ando, Hyuma Makizako, Hiroyuki Shimada, Daisuke Yoshida, Kengo Ito, Takashi Kato, Takao SuzukiAbstract:BACKGROUND Dual-task walking is believed to be more cognitively demanding than normal walking and alters trunk movement among older adults. However, the possible association between brain atrophy and spatiotemporal gait parameters, particularly during dual-task walking, is poorly understood. In this study, we examined the relationship between dual-task walking and brain atrophy. METHODS One hundred ten elderly adults (aged 65-94 years, women n = 55) underwent magnetic resonance imaging scanning and gait experiments under normal and dual-task walking conditions. Linear acceleRations of the trunk were measured in vertical, anteroposterior, and mediolateral directions using a triaxial accelerometer attached to the lower trunk. Gait speed, stride length, and cadence were recorded. The Harmonic Ratio, a measure of trunk stability, was computed separately in each direction to evaluate the smoothness of trunk movement during walking. Brain atrophy was quantitatively assessed using magnetic resonance image data. RESULTS Gait speed, stride length, cadence, and Harmonic Ratio in all directions were lower in dual-task walking than in normal walking (p < .05). The dual-task-related changes in Harmonic Ratio were independently correlated with brain atrophy adjusted for subject characteristics only in the vertical direction (p < .05). CONCLUSIONS Our findings support the hypothesis that dual-task walking is more cognitively demanding than normal walking. Decreased trunk stability during dual-task walking is associated with brain atrophy. Additional studies are necessary to elucidate the effects of regional brain atrophy on the control of walking.
Kota Tsutsumimoto - One of the best experts on this subject based on the ideXlab platform.
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Effects of white matter lesions on trunk stability during dual-task walking among older adults with mild cognitive impairment.
Age (Dordrecht Netherlands), 2015Co-Authors: Takehiko Doi, Kota Tsutsumimoto, Hyuma Makizako, Hiroyuki Shimada, Ryo Hotta, Sho Nakakubo, Takao SuzukiAbstract:The linkage between gait and cognition has been shown in cases of white matter lesion (WML) that affect gait in older adults. Dual-task walking is believed to be cognitively demanding and to alter trunk movement, and gait impairment in people with mild cognitive impairment (MCI) is highlighted under this condition. However, the association between dual-task walking and structural changes in the brain, particularly with WML, in people with MCI is still unclear. The aim of this study was to examine the association between trunk stability during dual-task walking and WML in 560 older adults with MCI. We measured magnetic resonance imaging (MRI) and gait variables. Gait variables included Harmonic Ratio in vertical, mediolateral, and anteroposterior directions, analyzed using a tri-axial accelerometer attached to the lower trunk. Walking conditions were normal walking and dual-task walking (counting backwards while walking) conditions. Demographical data and brain atrophy were measured as covariates. Subjects were classified into non-severe WML (n = 451, mean age = 73.2 years) and severe WML (n = 109, mean age = 75.9 years) groups. Linear mixed-effects model analysis controlled for covariates showed dual-task-related changes in all Harmonic Ratios associated with WML (p < 0.05). Even after adjustment for executive function, Harmonic Ratio in the mediolateral direction was significantly associated with WML (p < 0.05). Our findings revealed that WMLs were associated with trunk stability in dual-task walking. Further studies are required to investigate the neural basis for deficits in gait ability among MCI subjects.
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The Harmonic Ratio of trunk acceleRation predicts falling among older people: results of a 1-year prospective study
Journal of NeuroEngineering and Rehabilitation, 2013Co-Authors: Soichiro Hirata, Kota Tsutsumimoto, Shogo Misu, Hiroshi AndoAbstract:Background Gait variables derived from trunk accelerometry may predict the risk of falls; however, their associations with falls are not fully understood. The purpose of the study was to determine which gait variables derived from upper and lower trunk accelerometry are associated with the incidence of falls, and to compare the discriminative ability of gait variables and physical performance. Methods This study was a 1-year prospective study. Older people ( n = 73) walked normally while wearing accelerometers attached to the upper and lower trunk. Participants were classified as fallers ( n = 16) or non-fallers ( n = 57) based on the incidence of falls over 1 year. The Harmonic Ratio (HR) of the upper and lower trunk was measured. Physical performance was measured in five chair stands and in the timed up and go test. Results The HR of the upper and lower trunk were consistently lower in fallers than non-fallers ( P < 0.05). Upper trunk HR, was independently associated with the incidence of falls ( P < 0.05) after adjusting for confounding factors including physical performances. Consequently, upper trunk HR showed high discrimination for the risk of falls (AUC = 0.81). Conclusions HR derived from upper trunk accelerometry may predict the risk of falls, independently of physical performance. The discriminative ability of HR for the risk of falls may have some validity, and further studies are needed to confirm the clinical relevance of trunk HR.
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the Harmonic Ratio of trunk acceleRation predicts falling among older people results of a 1 year prospective study
Journal of Neuroengineering and Rehabilitation, 2013Co-Authors: Takehiko Doi, Soichiro Hirata, Kota Tsutsumimoto, Shogo Misu, Rei Ono, Hiroshi AndoAbstract:Gait variables derived from trunk accelerometry may predict the risk of falls; however, their associations with falls are not fully understood. The purpose of the study was to determine which gait variables derived from upper and lower trunk accelerometry are associated with the incidence of falls, and to compare the discriminative ability of gait variables and physical performance. This study was a 1-year prospective study. Older people (n = 73) walked normally while wearing accelerometers attached to the upper and lower trunk. Participants were classified as fallers (n = 16) or non-fallers (n = 57) based on the incidence of falls over 1 year. The Harmonic Ratio (HR) of the upper and lower trunk was measured. Physical performance was measured in five chair stands and in the timed up and go test. The HR of the upper and lower trunk were consistently lower in fallers than non-fallers (P < 0.05). Upper trunk HR, was independently associated with the incidence of falls (P < 0.05) after adjusting for confounding factors including physical performances. Consequently, upper trunk HR showed high discrimination for the risk of falls (AUC = 0.81). HR derived from upper trunk accelerometry may predict the risk of falls, independently of physical performance. The discriminative ability of HR for the risk of falls may have some validity, and further studies are needed to confirm the clinical relevance of trunk HR.
