Development of iot-based agility timer prototype and classification of agility

To date, there is limited specific device available that can measure agility time and deficient study has been conducted to study agility classification. Thus, the aim of this study is to develop an Internet of Things (IoT)-based agility timer prototype with appropriate agility experiment protocol to evaluate the agility time of combat sports athletes and perform agility profiling using supervised machine learnings. The main components of the prototype consisted of an Arduino NodeMCU board, a vibration sensor, an organic light-emitting diode (OLED), three visual stimuli (red, green and yellow LEDs) and an audio stimulus (buzzer). Through the integration with the Blynk app, the data obtained can be viewed not only on the OLED display but on Blynk App too. Prototype assessment by means of statistical analysis was found to be valid (R = 0.998, R 2 = 0.997, p < 0.05), reliable (ICC ≥ 0.9) and accurate (0.06 - 0.084 RMSE). Fifty combat sports athletes (26 Silat and 24 Taekwondo athletes) were recruited to undergo two agility experiments: Simple Agility Time (SAT) and Multiple-Choice Agility Time (MCAT). It was found that 80 % of the participants were more responsive towards the audio stimulus as compared with the visual stimulus. In terms of visual cognition, 40 % of the subjects were more responsive towards the red LED stimulus in comparison with the yellow LED and green LED stimuli. Next, supervised Support Vector Machine (SVM), K-Nearest Neighbor (KNN) and Artificial Neural Network (ANN) were implemented to classify agility time into three classes, which were high, medium and low based on two inputs: agility time and body mass index (BMI). The classification benchmark was determined based on the agility time threshold range. The findings revealed that the best supervised classifier model was ANN, which gave 100 % accuracy for each stimulus. Next, an agility calculator based on the ANN model was developed to obtain the athletes’ agility class. In conclusion, a valid, reliable and accurate IoT-based agility timer prototype was successfully developed to assess the agility time of combat sports athletes, and an agility calculator based on the ANN model was created to obtain the agility class of athletes

The effect of leadership styles, social capital, and entrepreneurial orientation on organizational effectiveness of social welfare organizations in Malaysia

This study provided a rare opportunity to thoroughly discuss the hampered effectiveness of the Social Welfare Organizations in Malaysia. In line with the above, this study aimed to examine the effect of leadership styles, social capital and entrepreneurial orientation on organizational effectiveness of the Social Welfare Organizations. In this quantitative research, simple random sampling was adopted as the sampling technique to draw conclusions about the entire population. Usable responses were received from 134 Social Welfare Organizations, which accounted to a 56.07% response rate. A combination of IBM SPSS statistical software version 22.0 (SPSS) and the Partial Least Square Structural Equation Modeling (PLS-SEM) was used as the statistical tools to analyse the collected data. Drawing upon the Resource-Based View Theory, the results indicated that the seven main hypotheses (both the direct and mediating hypotheses) were supported, whereas only eight out of fifteen sub-hypotheses were supported. In brief, the findings demonstrated the positive impact of leadership styles, social capital and entrepreneurial orientation on the organizational effectiveness of the Social Welfare Organizations in Malaysia. Also, this research provided evidence that entrepreneurial orientation had a full mediating effect on the relationship between leadership style and organizational effectiveness, while there was partial mediating effect on the relationship between social capital and organizational effectiveness. Correspondingly, Social Welfare Organizations should be encouraged to adopt those practices to enhance the effectiveness of their organizations. Further, the implications, limitations and suggestions of the study were discussed. It was also suggested that the policy-makers should focus on creating awareness regarding the importance of the social aspects and provide supportive national policies which could enhance the organizational effectiveness of Social Welfare Organizations

The role of macrophage phenotypes in atherosclerosis

Background and aim: The rupture of atherosclerotic plaque is the key underlying cause of cardiovascular episodes including heart attack and stroke. A key contributor to plaque instability is the macrophage. We found that while M1 macrophages are associated with plaque instability, M2 macrophages are not; rather they produce matrix molecules such as collagen that provide structural integrity to the cap. Modulating the balance of macrophage phenotypes in the plaques may hence be a treatment option. However, since some matrices, particularly the proteoglycans, can retain lipoproteins in the arterial wall, this study examined what proteoglycans M1 and M2 macrophages produce, and how is their degree of lipid binding. Method: Human monocyte-like THP-1 cells or the monocytes isolated from healthy donors were differentiated into M1 and M2 macrophages (and foam cells). The structure and low-density lipoprotein (LDL) binding ability of the proteoglycans were assessed. Results: M1 and M2 macrophages secreted a range of proteoglycans such as biglycan, perlecan and versican, with M2 macrophages producing more perlecan and versican. The glycosaminoglycan (GAG) chains decorating the core protein of these proteoglycans included chondroitin sulphate and heparan sulphate. The chondroitin sulphate produced by M1 macrophages were more sulphated than M2. Heparan sulphate from both cells included non-sulphated and sulphated disaccharides, with the latter being more abundant in the M1. The M1 proteoglycans bound more LDL than those of M2 and this was mediated by heparan sulphate. In contrast, LDL binding sites were found on the M2 proteoglycan core proteins, such as perlecan, with increased LDL binding evident upon cleavage of GAGs. M2 macrophages were co-localised with perlecan and lipid accumulation in plaques, suggesting that they may help in LDL retention via perlecan. When M1 and M2 macrophages transformed into foam cells, they produced less proteoglycans. However, the proteoglycans did not differ in the degree of LDL binding between the phenotypes. Conclusion: Both M1 and M2 macrophages produced proteoglycans that could bind LDL, but in different ways: the M1 macrophage-derived proteoglycans bound LDL via heparan sulphate, whereas those produced by M2 macrophages used core proteins to bind LDL. Therefore, M1 and M2 macrophages are likely to contribute to LDL retention during the development of atherosclerosis

A Composite Likelihood-based Approach for Change-point Detection in Spatio-temporal Process

This paper develops a unified, accurate and computationally efficient method for change-point inference in non-stationary spatio-temporal processes. By modeling a non-stationary spatio-temporal process as a piecewise stationary spatio-temporal process, we consider simultaneous estimation of the number and locations of change-points, and model parameters in each segment. A composite likelihood-based criterion is developed for change-point and parameters estimation. Asymptotic theories including consistency and distribution of the estimators are derived under mild conditions. In contrast to classical results in fixed dimensional time series that the asymptotic error of change-point estimator is $O_{p}(1)$, exact recovery of true change-points is guaranteed in the spatio-temporal setting. More surprisingly, the consistency of change-point estimation can be achieved without any penalty term in the criterion function. A computational efficient pruned dynamic programming algorithm is developed for the challenging criterion optimization problem. Simulation studies and an application to U.S. precipitation data are provided to demonstrate the effectiveness and practicality of the proposed method