Search Results (9)

Background/Objectives: Global warming and the rise in the average temperature in recent years have increased the risk of heat stroke and also deteriorated performance among athletes. Kendo, a traditional Japanese martial art and also a competitive sport, is reported to have high incidents of heat stroke and related mortality. However, there is no heat management guideline for this specific sport to date and research on its heat management practices and risk factors for heat stroke are limited. The present study conducted a scoping review on studies focused on heat stress and the heat management practices of Kendo players. Methods: A literature search was conducted using five databases (PubMed, SCOPUS, Ichu-shi Web, CiNii, and Google Scholar) and also manually from the references of searched articles. Results: Overall, the studies that have investigated the heat stress of Kendo players are scarce and outdated. Of the 15 references that met screening criteria, 11 studies were conducted in a field setting. The vast majority were conducted on male university students and there was a lack of research on females and on different age groups. Common measures of heat management practices used in previous studies were weight changes before and after training (n = 14), body temperature (n = 9), and heart rate (n = 8). Only a few studies used multiple measures to determine heat stress. Conclusions: Considering the continuation of global warming and the increasing risk of heat stroke, further investigation on heat stress, its association with health and performance, and current heat management practices in Kendo players are warranted. Full article

In Kendo, there is no consensus as to which hand should produce more pressure when attacking the opponent with the bamboo sword, let alone how to teach the pressure distribution during coaching. There is the theory that a Kendo attack can be divided into five phases, which has not entered the coaching practice, either. The aim of this study was to measure the grip pressure during Kendo attacks, investigate the pressure distribution between the two hands, and find evidence for the existence of the alleged five attack phases. We instrumented a bamboo sword with grip pressure sensors and investigated the grip pressure in 23 participants. In all attack targets and in both hands, the pressure across all attack phases was significantly different. In general, the left-hand pressure was consistently and significantly higher than the right-hand one, across all five attack phases, for the hand, head, and flank attack targets. The surprising exception was the throat target with only two attack phases, the strike phase of which showed a greater pressure in the right hand. Across all participants, the left-hand pressure was greater in 60.22–100% in any phase of the four attack targets, except for the strike phase of the throat target. Through these results, we could verify the effect of the teaching customs in Kendo, as well as provide first-time evidence of the existence of the five attack phases. Full article

The standard HEVC codec and its extension for coding multiview videos, known as MV-HEVC, have proven to deliver improved visual quality compared to its predecessor, H.264/MPEG-4 AVC’s multiview extension, H.264-MVC, for the same frame resolution with up to 50% bitrate savings. MV-HEVC’s framework is similar to that of H.264-MVC, which uses a multi-layer coding approach. Hence, MV-HEVC would require all frames from other reference layers decoded prior to decoding a new layer. Thus, the multi-layer coding architecture would be a bottleneck when it comes to quicker frame streaming across different views. In this paper, an HEVC-based Frame Interleaved Stereo/Multiview Video Codec (HEVC-FISMVC) that uses a single layer encoding approach to encode stereo and multiview video sequences is presented. The frames of stereo or multiview video sequences are interleaved in such a way that encoding the resulting monoscopic video stream would maximize the exploitation of temporal, inter-view, and cross-view correlations and thus improving the overall coding efficiency. The coding performance of the proposed HEVC-FISMVC codec is assessed and compared with that of the standard MV-HEVC’s performance for three standard multi-view video sequences, namely: “Poznan_Street”, “Kendo” and “Newspaper1”. Experimental results show that the proposed codec provides more substantial coding gains than the anchor MV-HEVC for coding both stereo and multi-view video sequences. Full article

The purpose of this study was to clarify coaches’ competencies (COM) regarding dual-career (DC) support for student athletes in Japan. The questionnaire survey was conducted at 31 universities with an online survey URL that was distributed to 300 collegiate athletic coaches. In total, there were 152 respondents (female, 19; male, 133; mean age, 43.15 ± 12.07 years; coaching experience, 12.83 ± 9.72 years). The online survey adopted a Japanese-translated version of the Dual-Career Competency Questionnaire (DCCQ), which has been translated into nine languages and is widely used in European counties. The scale consists of six factors and 33 items, each rated on a five-point scale of importance (IM) and possession (PO). The Japanese version of the DCCQ was validated through a confirmatory factor analysis, and the internal consistency of the items was confirmed by calculating the Cronbach’s alpha coefficient. In addition, we examined differences between the IM and PO for DC support by t-tests and by calculating effect sizes. The validity and reliability of the Japanese version of the DCCQ were confirmed based on the goodness-of-fit index and Cronbach’s alpha coefficients, respectively. Our examination of the differences between IM and PO in DC support revealed that coaches perceived the importance of DC support but did not possess the necessary COM to offer DC support. That finding was similar to those of previous European studies. In particular, the Japanese coaches who participated in our online survey recognized the importance of COM in terms of “collaboration with various stakeholders and departments” for DC support but did not feel as though they held sufficient COM in that regard. In other words, the improvement of DC support requires the development of a coaching program that fosters COM to work with various stakeholders. This key insight provides a direction and specific focus for programs to improve coaches’ DC support for student athletes. Full article

This article is focused on the creation of a data model of an information system to support the processes of population sheltering (PoS). PoS processes have undergone significant changes in the Czech Republic. The PoS system was transformed for the use of improvised shelters. For sustainable PoS, it is necessary to standardize the approach of crisis management staff. Key research hypotheses: the data model must respect the methodological framework of planning and implementation of the PoS, especially when used for the design and implementation of the improvised shelters; the standardization of residential buildings can be used to facilitate and streamline the sustainable process of planning of the PoS; the unified data model of the PoS can be considered suitable for standardization and development in the field of sustainable planning and implementation of the PoS. Softwares such as SW QGIS desktop 2.6.0, OpenStreetMap (OSM) spatial database, ESRI shapefile format, and S-JTSK/Krovak East North 5514 coordinate system were used for the verification of the spatial data model, and ASP.NET MVC 4.7.2 Microsoft SQL Server Express 2019, jQuery 3.3.1, Bootstrap 3.4.1, Kendo UI 2019.1.220, and virtual Windows Server 2016 were used for the implementation of the physical data model. The physical data model substantiates the benefits. Full article

In Kendo, the ability to execute a technique within the shortest time is essential for winning. The purpose of this study was to utilise an in-house developed automatic headgear-scoring sensor with a buzzer to determine the auditory response reaction time (ARRT) of professional (PK) and amateur (AK) Kendo practitioners. ARRT is defined as the time required for a participant to hit a target after a buzzer is sounded. A total of 14 participants took part in this study. The participants were requested to hit the opponent’s headgear target, which consisted of a pressure sensor, upon hearing the buzzer. The average reaction time of PK is 0.44 s, and for AK 0.58 s, with a significant difference between the two groups (p < 0.0001). The in-house developed automatic headgear-scoring sensor with buzzer can be utilised to assist a Kendo practitioner in training to shorten the response reaction time to improve competition performance. Full article

Glecaprevir/pibrentasvir (G/P) are direct-acting antivirals (DAAs) that achieve a high sustained virological response (SVR) rate for hepatitis C virus (HCV) infection. We investigated G/P effectiveness for HCV patients based on real-world experience and the clinical features of retreatment cases. HCV patients (n = 182) were compared for clinical features and outcomes between first treatment (n = 159) and retreatment (n = 23) G/P groups. Overall, 77 patients (42.3%) were male, the median age was 68 years, and 86/66/1/4 cases had genotype 1/2/1 + 2/3, respectively. An SVR was achieved in 97.8% (178/182) of cases by intention-to-treat analysis and 99.4% (178/179) of cases by per-protocol analysis. There were no remarkable differences between the first treatment and retreatment groups for male (42.8% vs. 39.1%, p = 0.70), median age (68 vs. 68 years, p = 0.36), prior hepatocellular carcinoma (5.8% vs. 8.7%, p = 0.59), or the fibrosis markers AST-to-platelet ratio index (APRI) (0.5 vs. 0.5, p = 0.80) and fibrosis-4 (FIB-4) index (2.2 vs. 2.6, p = 0.59). The retreatment group had a significantly more frequent history of interferon treatment (12.3% vs. 52.2%, p < 0.01) and the Y93H mutation (25.0% vs. 64.7%, p = 0.02). The number of retreatment patients who had experienced 3, 2, and 1 DAA treatment failures was 1, 3, and 19, respectively, all of whom ultimately achieved an SVR by G/P treatment. In conclusion, G/P was effective and safe for both HCV first treatment and retreatment cases despite the retreatment group having specific resistance mutations for other prior DAAs. As G/P treatment failure has been reported for P32 deletions, clinicians should consider resistance mutations during DAA selection. Full article

Complex human behavior, including interlimb and interpersonal coordination, has been studied from a dynamical system perspective. We review the applications of a dynamical system approach to a sporting activity, which includes continuous, discrete, and switching dynamics. Continuous dynamics identified switching between in- and anti-phase synchronization, controlled by an interpersonal distance of 0.1 m during expert kendo matches, using a relative phase analysis. In the discrete dynamical system, return map analysis was applied to the time series of movements during kendo matches. Offensive and defensive maneuvers were classified as six coordination patterns, that is, attractors and repellers. Furthermore, these attractors and repellers exhibited two discrete states. Then, state transition probabilities were calculated based on the two states, which clarified the coordination patterns and switching behavior. We introduced switching dynamics with temporal inputs to clarify the simple rules underlying the complex behavior corresponding to switching inputs in a striking action as a non-autonomous system. As a result, we determined that the time evolution of the striking action was characterized as fractal-like movement patterns generated by a simple Cantor set rule with rotation. Finally, we propose a switching hybrid dynamics to understand both court-net sports, as strongly coupled interpersonal competition, and weakly coupled sports, such as martial arts. Full article

Kendo is one of the most ancient swordsmanship arts in Japan. The aims of this study are to develop and test an innovative smart Kote glove for assisting the Kendoka to distinguish scoring from non-scoring Kote (wrist) strikes. An in-house developed pressure sensing platform was utilized to develop the smart Kote glove. Ten kendo practitioners, comprising of five Dan (black belts equivalent) and five Kyu (lower level/ungraded of both genders), participated in this study. The results showed significant differences between Dan and Kyu participants in both accuracy and sharpness of the strikes. Dan grade participants showed higher percentage of hitting the target comparing to Kyu grade (92% and 75% respectively). The percentage of scoring was also significantly higher in Dan (78%) than in Kyu (37%) grades. The average impact force of scoring by Dan grade (1159 ± 379 N) was higher than by Kyu grade (852 ± 429 N). Full article