FACTOR ANALYSIS OF SPRINT PHASES ON THE SPEED CURVE OF THE 100M DASH

Previous studies have indicated that the speed curve of the 100m dash consists of some distinct phases which can be used to analyze an athlete's performance. The purpose of this study was to introduce a method using a portable computer as a device for the measurement of sprint time and the illustration of the speed curve, and to clarify a simple model of sprint phases on the factor structure. Based on the data of 133 participants, principal factor solution was given to the correlation matrix, and varimax rotation was applied to simplify the factorial structure of sprint phases. Finally, two factors were extracted and interpreted. It is suggested that this method is useful for measurement and evaluation in the 100m dash, and that a simple model of sprint phases may be explained by these two factors. These findings are important in predicting the ability of 100m sprinters and in considering coaching methods in terms of technique, training, strategy, etc

Mechanism of cardiac arrhythmias induced by epinephrine in dogs with hypokalemia

To investigate the mechanism of ventricular arrhythmias induced by epinephrine in dogs with hypokalemia, 30 adult mongrel dogs were separated into a control group (n = 13) and a hypokalemia group (n = 17). In the hypokalemia group, sodium polystyrene sulfonate (5 g/kg body weight) was infused into the colon. In both groups, the serum concentrations of sodium, potassium and calcium were measured every 15 minutes for 60 minutes. The mean ( ± standard deviation) serum potassium level of the hypokalemia group decreased significantly from 3.81 ± 0.21 to 2.92 ± 0.36 mEq/liter; there were no significant changes in other electrolytes. After 60 minutes, epinephrine (10 μg/kg) was injected intravenously in the hypokalemia and control groups, and the arrhythmia ratio (the number of ventricular ectopic beats divided by the total heart rate) was calculated for 5 minutes. Each group was further classified into subgroups of dogs with an arrhythmia ratio higher or lower than 10%. An arrhythmia ratio over 10% was observed in 7.7% of the control group and 53% of the hypokalemia group.Immediately after 5 minutes of epinephrine injection, myocardial mitochondria and plasma membrane fraction were prepared from each group. Mitochondrial calcium content and phospholipase activity of plasma membrane fraction were determined. Significant increases in both mitochondrial calcium content and phospholipase activity were observed in the dogs with hypokalemia and an arrhythmia ratio greater than 10%. In the hypokalemia group, there was a clear reciprocal correlation (r = − 0.79) between serum potassium concentration at 60 minutes and mitochondrial calcium content, and a clear correlation (r = 0.80) between mitochondrial calcium content and phospholipase activity. It was also demonstrated that the dogs with a higher than 10% arrhythmia ratio had a low serum potassium concentration, high mitochondrial calcium content and high phospholipase activity. These results suggest that hypokalemia enhances the calcium influx induced by epinephrine, resulting in activation of phospholipase, which is responsible for the development of ventricular arrhythmias

Behavior of Latent Vector of Trivariate Wishart Matrix

This paper is concerned with the probability density function of the latent vector corresponding to the largest latent root of Wishart matrix. The latent vector may be expressed by the polar coordinates. Sugiyama (1966) give the exact expression of the probability density function of the polar coordinates. The function contained the alternating series, thus the function may not be converged on the domain of definition, numerically. In this paper we derived an improved expression of the function to be the positive series, for which we provide graphs of a population latent vector and latent roots.【査読有

Inverted type bulk-heterojunction organic solar cell using electrodeposited titanium oxide thin films as electron collector electrode

金沢大学理工研究域物質化学系We developed an inverted type bulk-heterojunction organic solar cell with 1 cm2 active area using a fluorine-doped tin oxide/electrodeposited amorphous (TiOx) or anatase (TiO2) titanium oxide electrode instead of the low work-functional electrode such as Al. The cell with TiO2 showed the power conversion efficiency (η) of 2.5% by irradiating AM 1.5-100 mW cm- 2 simulated sunlight. While, the performance of the cell with TiOx was almost maintained in an ambient atmosphere under continuous light irradiation of 10 h, although slightly small initial η value of 2.1% was observed. Crown Copyright © 2008

Inverted bulk-heterojunction organic solar cell using chemical bath deposited titanium oxide as electron collection layer

金沢大学理工研究域物質化学系Chemical bath deposited titanium oxide (TiOx ) as an electron collection layer is introduced between the organic layer and the indium tin oxide (ITO) electrode for improving the performance of inverted bulk-heterojunction organic thin film solar cells with 1 cm2 active area, where regioregular poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61 butyric acid methyl ester (PCBM) were mainly used as the photo-active layer. The uniform and thin TiOx film was easily prepared onto the ITO electrode in air by simple chemical bath deposition method. The cell performance was almost maintained in an ambient atmosphere under continuous light irradiation of 100 h despite non-sealing. The cell with bulk-heterojunction organic thin film consisted of [6.6] diphenyl C62 bis(butyric acid methyl ester) (bis-PCBM) and P3HT prepared under best condition showed the power conversion efficiency (PCE) of 3.8% under the AM1.5G simulated sunlight. © 2010 Elsevier B.V. All rights reserved

Multifrequency VLBI Observations of the Broad Absorption Line Quasar J1020+4320: Recently Restarted Jet Activity?

This paper reports very-long-baseline interferometry observations of the radio-loud broad absorption line (BAL) quasar J1020+4320 at 1.7, 2.3, 6.7, and 8.4 GHz using the Japanese VLBI network (JVN) and European VLBI network (EVN). The radio morphology is compact with a size of ~10 pc. The convex radio spectrum is stable over the last decade; an observed peak frequency of 3.2 GHz is equivalent to 9.5 GHz in the rest frame, suggesting an age of the order of ~100 years as a radio source, according to an observed correlation between linear size and peak frequency of compact steep spectrum (CSS) and giga-hertz peaked spectrum (GPS) radio sources. A low-frequency radio excess suggests relic of past jet activity. J1020+4320 may be one of the quasars with recurrent and short-lived jet activity during a BAL-outflowing phase.Comment: 7 pages, 2 figures, 2 tables, accepted for publication in PAS