This paper shows that an arbitrary Gaussian pure state can be deterministically generated in a dissipative open system that has quasilocal interactions between the subsystems and couples to the surrounding environment in a local manner. A quasilocal interaction, which means that the interaction occurs among only a few subsystems, is a crucial requirement for practical engineering of a dissipative system. The key idea is that first an auxiliary system having a local interaction with the environment is prepared and then that auxiliary system is coupled to the underlying target system via a set of two-body Hamiltonians in such a way that a desired pure state is generated. Moreover, we show that even with a simple single-mode auxiliary system, the deterministic generation of an arbitrary approximate Gaussian cluster state is possible, by devising an appropriate switching scheme. We discuss in a specific example how much a dissipation-induced pure Gaussian state can be perturbed by decoherence and parameter error.

The purpose of this study was to compare the snatch techniques of Japanese and international female weightlifters. Two high-speed cameras operating at 250 Hz were used to record the snatch lifts of the 5 best weightlifters in the snatch and 5 Japanese weightlifters during the 2008 Asian Weightlifting Championships held in Japan. The results revealed that the forward velocity of the barbell for the Japanese weightlifters during the second pull was significantly greater than that for the best weightlifters and that barbell trajectories of Japanese weightlifters except for the 53-kg class crossed the vertical reference line with great forward displacement of the barbell. In addition, the best weightlifters extended the knee and hip joints during the second pull earlier than the Japanese weightlifters did. These findings indicate that it is important to improve the way of pulling the barbell during the second pull for Japanese female weightlifters.

The purpose of the study was to examine the factors contributing to performance of a side medicine-ball throw (S-MBT) and a fast side medicine-ball throw (FS-MBT) and to analyze some of the factors which account for the difference in side medicine ball throw performance between the sexes. Sixteen males and ten females were evaluated by S-MBT, FS-MBT, isometric maximal trunk rotation torque (IMTRT), One repetition maximum of Parallel Squat (1RM(PS)) and Bench Press (1RM(BP)), Bench Press peak power (BP(PP)), Static Squat Jump peak power (SSJ(PP)) and vertical jump height. Males demonstrated significantly greater scores than females in all measurements. Significant correlations were observed in males, but not in females, between the distances during S-MBT and the IMTRT values (r = 0.596-0.739, P < 0.05-0.01) and the 1RM(PS) values (r = 0.683-0.725, P < 0.01). In FS-MBT performance, significant correlations were observed in males, but not in females, between the ball velocity values during FS-MBT and the IMTRT values (r = 0.611-0.687, P < 0.05-0.01), 1RM(BP) values (r = 0.596-0.655, P < 0.05-0.01) and 1RM(PS) values (r = 0.679-0.718, P < 0.01). These results suggested that the contributing factors of S-MBT and FS-MBT performance were deferent in males and females. Hence, the side medicine-ball throw test would be useful to examine the trunk rotation power of male athletes, but may have a limited potential as a predictor of trunk rotation power for female athletes.

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Ikeda, Y, Sasaki, Y, and Hamano, R. Factors influencing spike jump height in female college volleyball players. J Strength Cond Res 32(1): 267-273, 2018-The purpose of this study was to examine factors influencing spike jump (SPJ) performance by female competitive volleyball players through comparisons of the kinematic data of SPJ with those of the standing long jump (SLJ) and vertical jump (VJ). Seventeen female competitive volleyball players were asked to perform SPJ, SLJ, and VJ. Motion data of SPJ including the approach phase were recorded. Regarding SLJ and VJ, jumping motion and ground reaction force were recorded during each performance. The results obtained showed that SPJ height correlated with vertical velocity at take-off, horizontal velocity at third step contact, and the deceleration of horizontal velocity from third step contact to take-off. Regarding the relationship among SPJ, SLJ, and VJ, the relationship between SPJ and SLJ was stronger than that with VJ. The contributions of the hip, knee, and ankle muscles to the propulsive phase of SLJ were 39.7%, 21.1%, and 39.2%, respectively, whereas their contributions to VJ were 36.2%, 30.2%, and 33.6%, respectively. The vertical velocity of SPJ at take-off correlated with hip work and ankle peak power in SLJ and knee peak power in VJ. These results suggest the importance of enhancing horizontal and vertical jumping abilities separately to improve the height of SPJ because the primary generator for power production seems to depend on jump direction.

This study investigated factors that determine the velocity of the center of mass (CM) and flight distance from a track start to devise effective technical and physical training methods. Nine male and 5 female competitive swimmers participated in this study. Kinematics and ground reaction forces of the front and back legs were recorded using a video camera and force plates. The track start was modeled as an inverted pendulum system including a compliant leg, connecting the CM and front edge of the starting block. The increase in the horizontal velocity of the CM immediately after the start signal was closely correlated with the rotational component of the inverted pendulum. This rotational component at hands-off was significantly correlated with the average vertical force of the back plate from the start signal to hands-off (r = .967, P < .001). The flight distance / height was significantly correlated with the average vertical force of the front plate from the back foot-off to front foot-off (r = .783, P < .01). The results indicate that the legs on the starting block in the track start play a different role in the behavior of the inverted pendulum.