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Hsu Y.-C.,National Taiwan University of Physical Education and Sport | Chen A.-P.,National Chiao Tung University
Neurocomputing | Year: 2014

In this study, a novel procedure combining computational intelligence and statistical methodologies is proposed to improve the accuracy of minimum-variance optimal hedge ratio (OHR) estimation over various hedging horizons. The time series of financial asset returns are clustered hierarchically using a growing hierarchical self-organizing map (GHSOM) based on the dynamic behaviors of market fluctuation extracted by measurement of variances, covariance, price spread, and their first and second differences. Instead of using original observations, observations with similar patterns in the same cluster and weighted by a resample process are collected to estimate the OHR. Four stock market indexes and related futures contracts, including Taiwan Weighted Index (TWI), Standard & Poor[U+05F3]s 500 Index (S&P 500), Financial Times Stock Exchange 100 Index (FTSE 100), and NIKKEI 255 Index, are adopted in empirical experiments to investigate the correlation between hedging horizon and performance. Results of the experiments demonstrate that the proposed approach can significantly improve OHR decisions for mid-term and long-term hedging compared with traditional ordinary least squares and naïve models. © 2014 Elsevier B.V.


Tsaih P.-L.,National Taiwan University | Shih Y.-L.,National Taiwan University of Physical Education and Sport | Hu M.-H.,National Taiwan University Hospital
American Journal of Physical Medicine and Rehabilitation | Year: 2012

Objective: The aim of this study was to investigate the effects of a taskoriented ambulation training program in regaining walking, balance, and activity of daily living performance for ambulation-challenged residents with walking potential in long-term care facilities. Design: Fifty ambulation-challenged residents with walking potential were randomly assigned to an individualized task-oriented ambulation training group (30-45 mins, three times a week) or a routine nursing care control group for 4 wks. Each subject was evaluated by a blind evaluator before and after training. Walking function was assessed using walking speed, the Timed Up and Go Test, and the 6-Minute Walk Test. Balance and activities of daily living were measured using the Berg Balance Scale and the Barthel Index, respectively. Results: The training group showed significantly more improvement in walking speed, time to complete the Timed Up and Go Test, and the total score of Berg Balance Scale from baseline to posttest than the control group did. No significant difference between groups was observed on the 6-Minute Walk Test or the Barthel Index. Conclusions: Ambulation-challenged residents with walking potential, as defined by slowing of walking speed with concomitant knee muscle weakness and joint range limitation, showed significant improvement in walking function and balance after a 4-wk task-oriented ambulation training in long-term care facilities. Copyright © 2012 Lippincott Williams & Wilkins.


Chen L.-J.,National Taiwan University of Physical Education and Sport | Stevinson C.,Loughborough University | Ku P.-W.,National Changhua University of Education | Ku P.-W.,National Yang Ming University | And 3 more authors.
International Journal of Behavioral Nutrition and Physical Activity | Year: 2012

Background: Limited research has explored the relationship between non-leisure-time physical activity (NLTPA), including domestic and work-related physical activities, with depressive symptoms. This study was designed to elucidate independent associations between leisure-time physical activity (LTPA), NLTPA, and specific parameters of physical activity (frequency, duration and intensity) with depressive symptoms in older adults.Methods: A total of 2,727 persons aged ≥ 65 years participating in the 2005 Taiwan National Health Interview Survey were studied. Depressive symptoms were measured by the Center for Epidemiological Studies Depression Scale. Information regarding energy parameters for each type of LTPA and NLTPA during the past 2-week period was analyzed. After adjusting for socio-demographic variables, lifestyle behaviors and health status, multivariate logistic regression models were used to compute adjusted odds ratios (AOR) for LTPA and NLTPA for predicting depressive symptoms.Results: LTPA but not NLTPA was significantly associated with depressive symptoms. Compared with participants expending 2000+ kcal/week through LTPA, the risk of experiencing depressive symptoms was significantly higher for those expending 1-999 kcal/week (AOR = 2.06, 95% CI: 1.25-3.39), and those who expending 0 kcal/week (AOR = 3.72, 95%CI: 2.28-6.06). Among the three parameters of LTPA (intensity, duration and frequency) examined, only intensity was independently associated with depressive symptoms.Conclusions: These findings imply that exercise recommendations for older adults should emphasize the importance of higher intensity activity, rather than frequency or duration, for improved mental well-being. However, well-designed prospective cohort studies or intervention trials are needed to confirm these findings. © 2012 Chen et al; licensee BioMed Central Ltd.


Hsu C.-J.,China Medical University at Taichung | Wu M.-H.,China Medical University at Taichung | Wu M.-H.,National Taiwan University of Physical Education and Sport | Chen C.-Y.,China Medical University at Taichung | And 4 more authors.
Cell Communication and Signaling | Year: 2013

Chemokine (C-C motif) ligand 3 (CCL3), also known as macrophage inflammatory protein-1α, is a cytokine involved in inflammation and activation of polymorphonuclear leukocytes. CCL3 has been detected in infiltrating cells and tumor cells. Chondrosarcoma is a highly malignant tumor that causes distant metastasis. However, the effect of CCL3 on human chondrosarcoma metastasis is still unknown. Here, we found that CCL3 increased cellular migration and expression of matrix metalloproteinase (MMP)-2 in human chondrosarcoma cells. Pre-treatment of cells with the MMP-2 inhibitor or transfection with MMP-2 specific siRNA abolished CCL3-induced cell migration. CCL3 has been reported to exert its effects through activation of its specific receptor, CC chemokine receptor 5 (CCR5). The CCR5 and AMP-activated protein kinase (AMPK) inhibitor or siRNA also attenuated CCL3-upregulated cell motility and MMP-2 expression. CCL3-induced expression of MMP-2 and migration were also inhibited by specific inhibitors, and inactive mutants of AMPK, p38 mitogen activated protein kinase (p38 or p38-MAPK), and nuclear factor κB (NF-κB) cascades. On the other hand, CCL3 treatment demonstrably activated AMPK, p38, and NF-κB signaling pathways. Furthermore, the expression levels of CCL3, CCR5, and MMP-2 were correlated in human chondrosarcoma specimens. Taken together, our results indicate that CCL3 enhances the migratory ability of human chondrosarcoma cells by increasing MMP-2 expression via the CCR5, AMPK, p38, and NF-κB pathways. © 2013 Hsu et al.; licensee BioMed Central Ltd.


Chen F.-C.,National Pingtung University of Science and Technology | Wu S.-K.,National Taiwan University of Physical Education and Sport
Motor Control | Year: 2013

The purpose of this study was to examine the relationships between perceived hole size (perception), performance, and body movement (action) in golf putting for children with probable developmental coordination disorder (DCD) and typically developing children (TDC). Forty-eight children (24 probable DCD, 24 TDC) performed putting in easy and hard conditions. Body movement was measured during putting, performance was measured as the distance between ball and hole, and perceived hole size was recorded using a Microsoft Paint drawing exercise 1 m away from the hole. The present results revealed that perceived hole size was positively related to putting performance, body movement was negatively associated with putting performance, and that there were negative correlations between body movement and perceived hole size. While children with probable DCD tended to perceive the hole as smaller, perform worse, and show more body movement, TDC exhibited the opposite. These findings help characterize the relationships between perception, performance, and action in children with probable DCD and TDC during golf putting. © 2013 Human Kinetics, Inc.


Chen F.C.,National Pingtung University of Science and Technology | Tsai C.L.,National Cheng Kung University | Wu S.K.,National Taiwan University of Physical Education and Sport
Experimental Brain Research | Year: 2014

Gibson (The ecological approach to visual perception, Houghton Mifflin, Boston, 1979/1986) defined affordances as opportunities for motor behaviors, and highly emphasized the interaction between perception and action. Research on children with developmental coordination disorder commonly reports difficulties in judgments of affordances (perception) and in postural control (action). However, how perception and action are coupled has not been studied yet. The present study sought to evaluate the relationship between control of postural sway and perception of affordances in children at risk for developmental coordination disorder (RDCD) and typically developing children (TDC). We hypothesized that the relationship between perception and action would differ between groups. Participants made a series of judgments about their maximum sitting height (SHmax) while standing with and without wearing 10 cm blocks on feet. Postural sway and the judgment accuracy were recorded. Our findings showed that RDCD swayed more during judgment sessions and made less accurate judgments compared to TDC. In addition, TDC reduced postural sway from inter-judgment to judgment sessions, whereas the postural sway of RDCD remained identical between sessions. Last, while TDC reduced postural sway across judgment trials and revealed a learning effect of the judgments about SHmax in the block condition, RDCD never modulated postural sway and did not learn their SHmax in both non-block and block conditions. Overall, modulation of postural sway differed between groups during judgment sessions and between inter-judgment and judgment sessions, whereby their perceptual judgments about SHmax were differentially influenced. To summarize, this study demonstrated a difference in perception and action coupling between RDCD and TDC. © 2014 Springer-Verlag.


Ku P.-W.,National Changhua University of Education | Stevinson C.,Loughborough University | Chen L.-J.,National Taiwan University of Physical Education and Sport
Journal of Epidemiology | Year: 2012

Background: Few studies have explored the relations between naturally occurring changes in physical activity and cognitive performance in later life. This study examined prospective associations between changes in physical activity and cognitive performance in a population-based sample of Taiwanese older adults during an 11-year period. Methods: Analyses were based on nationally representative data from the Taiwan Health and Living Status of the Elderly Survey collected in 1996, 1999, 2003, and 2007. Data from a fixed cohort of 1160 participants who were aged 67 years or older in 1996 and followed for 11 years were included. Cognitive performance (outcome) was assessed using 5 questions from the Short Portable Mental Status Questionnaire. Physical activity (exposure) was self-reported as number of sessions per week. The latent growth model was used to examine associations between changes in physical activity and cognitive performance after controlling for sociodemographic variables, lifestyle behaviors, and health status. Results: With multivariate adjustment, higher initial levels of physical activity were significantly associated with better initial cognitive performance (standardized coefficient β = 0.17). A higher level of physical activity at baseline (1996) was significantly related to slower decline in cognitive performance, as compared with a lower level of activity (β = 0.22). The association between changes in physical activity and changes in cognitive performance was stronger (β = 0.36) than the previous 2 associations. The effect remained after excluding participants with cognitive decline before baseline. Conclusions: Physical activity in later life is associated with slower age-related cognitive decline.© 2012 by the Japan Epidemiological Association.


Chen L.-J.,National Taiwan University of Physical Education and Sport | Fox K.R.,University of Bristol | Ku P.-W.,National Changhua University of Education | Ku P.-W.,National Yang Ming University | Taun C.-Y.,National Taiwan University of Physical Education and Sport
Journal of School Health | Year: 2013

BACKGROUND: This study examined the association between fitness change and subsequent academic performance in Taiwanese schoolchildren from 7th grade to 9th grade. METHODS: The 7th graders from 1 junior high school district participated in this study (N=669). Academic performance was extracted from school records at the end of each grade. Cardiovascular (CV) fitness, sit-and-reach flexibility, bent-leg curl-ups, and height and weight for calculating body mass index (BMI) were assessed at the start of each grade. RESULTS: The results showed that improvement in CV fitness, but not muscular endurance or flexibility, is significantly related to greater academic performance. A weak and nonsignificant academic-BMI relationship was seen. CONCLUSION: CV fitness exhibits stronger longitudinal associations with academic performance than other forms of fitness or BMI for adolescents. © 2013, American School Health Association.


Ku P.-W.,National Changhua University of Education | Ku P.-W.,National Yang Ming University | Fox K.R.,University of Bristol | Chen L.-J.,National Taiwan University of Physical Education and Sport | Chou P.,National Yang Ming University
American Journal of Preventive Medicine | Year: 2012

Background: Few studies have explored the reciprocal relationships between naturally occurring changes in physical activity and depressive symptoms in later life. Purpose: This study examined the reciprocal associations between changes in physical activity and depressive symptoms in a population-based sample of Taiwanese older adults over an 11-year period. Methods: Analyses were based on nationally representative data from the Taiwan's Health and Living Status of the Elderly Survey collected in 1996, 1999, 2003, and 2007. Data from the fixed cohort of 1160 participants aged ≥67 years in 1996 with 11 years of follow-up were studied. Depressive symptoms were assessed using the ten-item Chinese version of the Center for Epidemiologic StudiesDepression Scale. Physical activity was self-reported as the number of sessions per week. Latent growth modeling was used to examine the bidirectional associations between changes in physical activity and depressive symptoms when controlling for sociodemographic variables, lifestyle behaviors, and health status. Data analyses were completed in 2011. Results: With multivariate adjustment, initial levels of physical activity were negatively associated with changes in depressive symptoms (β=-0.34, p<0.05). In contrast, early depressive symptoms were not related to change in physical activity (β=-0.17, p>0.05). Conclusions: Physical activity engagement in later life is associated with a lower risk of subsequent depressive symptoms, but the reverse association is not supported. The finding has underlying implications for future physical activity and mental health promotion in aged populations. © 2012 American Journal of Preventive Medicine.


Hsu Y.-C.,National Taiwan University of Physical Education and Sport
ICIC Express Letters | Year: 2015

The discovery of the existence of implied pitching patterns in a baseball game is an interesting problem. Most previous studies have focused on ranking the pitchers according to their pitching statistics, and using these statistics to summarize the overall performance of the baseball team and predict the winner. In this study, we have proposed the use of the decision tree model in analyzing the pitching data collected from the 2012 Asia Series to recognize the characteristics of the baseball team. The empirical results indicate that the team can be identified using the pitcher’s sequence, pitching type, and pitching speed, with 82% accuracy. Results of the comparison of the model fitness for each team imply that the pitching pattern of the weak team is monotonous and more easily recognizable compared with the powerful team. © 2015, ICIC International.

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