KINEMATIC CHARACTERISTICS OF KICK START FOR ELITE COMPETITIVE JAPANESE MALE SPRINT SWIMMERS

The purpose of this study was to compare the kinematic characteristics of the kick start technique at the start phase demonstrated by male elite competitive sprint swimmers and male collegiate swimmers in consideration of the performance enhancement. An elite competitive sprint swimmer and eleven collegiate male swimmers performed maximal effort during competitive swimming at the start followed by 25 m crawl swim during experimental trials. The trials were recorded using three synchronized video cameras shooting at 60 fps. Two-dimensional video analysis was performed in the sagittal plane. Calculated variables at take-off were horizontal velocity, speed, attitude angle, angle of projection, whereas those at entry were entry angle, attitude angle, angle of attack. In addition, block time horizontal coordinates for start position and 15 m time were calculated. Based on the results of this study, the kick start technique for the top competitive sprint swimmer was characterized as having shorter block time and higher horizontal velocity at take-off

Capability Leapfrogging in the Japanese IT Services Industry

The focal question that we address is about how firms transition their IT product capabilities to the IT services capabilities. In particular, we were interested in exploring the unexpected observation that some incumbent firms in the Japanese IT industry were able to leapfrog capability development for transitioning to the IT services model, while others struggled to do so. We use a multi-method (Mingers 2001) approach consisting of four complementary stages for addressing the research question: (a) multiple case studies in eleven leading Japanese IT firms, (b) a large scale survey of division managers in 208 firms in Japan, (c) quantitative sequence analysis of archival product development logs for over 1,800 IT products in 208 Japanese firms during the ongoing transition, and (d) a Monte Carlo simulation of a subset of the insights obtained in the preceding stages

Wasserstein Gradient Flow over Variational Parameter Space for Variational Inference

Variational inference (VI) can be cast as an optimization problem in which the variational parameters are tuned to closely align a variational distribution with the true posterior. The optimization task can be approached through vanilla gradient descent in black-box VI or natural-gradient descent in natural-gradient VI. In this work, we reframe VI as the optimization of an objective that concerns probability distributions defined over a \textit{variational parameter space}. Subsequently, we propose Wasserstein gradient descent for tackling this optimization problem. Notably, the optimization techniques, namely black-box VI and natural-gradient VI, can be reinterpreted as specific instances of the proposed Wasserstein gradient descent. To enhance the efficiency of optimization, we develop practical methods for numerically solving the discrete gradient flows. We validate the effectiveness of the proposed methods through empirical experiments on a synthetic dataset, supplemented by theoretical analyses

Early-Onset Chronic Inflammatory Disease Associated with Maternal Microchimerism

Maternal microchimerism (mMc) refers to the presence of a small population of cells originating from the mother. Whether mMc leads to autoimmune responses in children remains controversial. We describe here an 11-year-old boy with persistent fever and elevated levels of C-reactive protein from infancy onward. During infancy, the patient presented with high fever, skin rashes, and hepatic dysfunction. Careful examination including a liver biopsy failed to reveal the cause. At 4 years old, petechiae developed associated with thrombocytopenia and positive anti-dsDNA autoantibodies. Steroid pulse therapy was effective, but the effect of low-dose prednisone was insufficient. At age 9, an extensive differential diagnosis was considered especially for infantile onset autoinflammatory disorders but failed to make a definitive diagnosis. On admission, the patient exhibited short stature, hepatosplenomegaly, generalized superficial lymphadenopathy, and rashes. Laboratory findings revealed anemia, elevated levels of inflammation markers, and hypergammaglobulinemia. Serum complement levels were normal. Serum levels of IL-6 and B-cell activating factor were elevated. Viral infections were not identified. Although HLA typing revealed no noninherited maternal antigens in lymphocytes, female cells were demonstrated in the patient’s skin and lymph nodes, suggesting that maternal microchimerism might be involved in the pathogenesis of fever without source in infants

Na-ion dynamics in Quasi-1D compound NaV2O4

We have used the pulsed muon source at ISIS to study high-temperature Na-ion dynamics in the quasi-one-dimensional (Q1D) metallic antiferromagnet NaV2O4. By performing systematic zero-field and longitudinal-field measurements as a function of temperature we clearly distinguish that the hopping rate increases exponentially above Tdiff=250 K. The data is well fitted to an Arrhenius type equation typical for a diffusion process, showing that the Na-ions starts to be mobile above Tdiff . Such results makes this compound very interesting for the tuning of Q1D magnetism using atomic-scale ion-texturing through the periodic potential from ordered Na-vacancies. Further, it also opens the door to possible use of NaV2O4 and related compounds in energy related applications.Comment: Accepted for publication in Journal of Physics: Conference Series (2014

ROLES OF THE EXTREMITIES DURING KICK START IN COMPETITIVE SWIMMING

This study was aimed at examining the role of the hands and feet at takeoff by measuring the forces applied to the starting block by the right/left hands and feet. A small, waterproof force plate and a three-axis force sensor (operating at 500 Hz) were placed at the front and back of a custom-made starting block with an inclination angle of 10�� and on the right and left sides of the front of the starting block, respectively, to measure the force exerted on the starting block. Five male collegiate competitive swimmers were requested to perform kick starts from the starting block. The rear and front feet had the greatest contribution to the horizontal and vertical velocities, respectively, at kick start. In addition, the hand and foot exerted downward and upward forces, respectively, to the vertical velocity at kick start, revealing bilateral differences in the horizontal and vertical velocities of the hand

A Cross-sectional Multivariate Analysis of the Relationship Between Dental Health and Metabolic Syndrome

Article信州医学雑誌 67(3): 167-181(2019)journal articl

DIFFERENCES IN STROKE TECHNIQUE TO EXERT HAND PROPULSION BEWEEN ADVANCED AND INTERMEDIATE SWIMMERS

The aim of this study was to investigate differences in hand propulsion exerted by advanced and intermediate swimmers during insweep and upsweep phases in the front crawl stroke. Swimmers wore pressure sensors on their hands while performing the front crawl stroke in the swimming pool where a motion capture system was set up. The hand propulsive drag (PD) and lift (PL) were estimated during the two phases. The advanced swimmers exerted more PD than PL (70% vs 30%) during the insweep phase and used a similar amount of PD to PL in the upsweep phase. The intermediate swimmers used a similar amount of PD to PL in the insweep phase and exerted more PD than PL in the upsweep phase (65% vs 35%). The advanced swimmers used the different technique to exert hand propulsion in the two phases as compared to the intermediate ones

Essential roles of angiotensin II in vascular endothelial growth factor expression in sleep apnea syndrome

SummaryBackgroundHypoxia-induced endothelial cell dysfunction has been implicated in increased cardiovascular disease associated with obstructive sleep apnea syndrome (OSAS). OSAS mediates hypertension by stimulating angiotensin II (Ang II) production. Hypoxia and Ang II are the major stimuli of vascular endothelial growth factor (VEGF), which is a potent angiogenic cytokine and also contributes to the atherogenic process itself.Methods & resultsWe observed serum Ang II and VEGF levels and peripheral blood mononuclear cell (PBMC) and neutrophil VEGF expression. Compared to controls, subjects with OSAS had significantly increased levels of serum Ang II and VEGF and VEGF mRNA expression in their leukocytes. To examine whether Ang II stimulates VEGF expression in OSAS, we treated PBMCs obtained from control subjects with Ang II and with an Ang II receptor type 1 (AT1) blocker, olmesartan. We observed an increased expression of VEGF in the Ang II-stimulated PBMCs and decreased in VEGF mRNA and protein expression in the PBMCs treated with olmesartan.ConclusionsThese findings suggest that the Ang II-AT1 receptors pathway potentially are involved in OSAS and VEGF-induced vascularity and that endothelial dysfunction might be linked to this change in Ang II activity within leukocytes of OSAS patients