A METHOD TO DETERMINE THE MOMENT OF BUOYANT FORCE ACTING ON FRONT-CRAWL SWIMMERS

The purpose of this study was to develop a method to determine the moment of buoyant force acting on a front-crawl swimmer about the longitudinal-axis (buoyancy torque). The buoyancy torque was determined using three-dimensional kinematic data of one swimming trial and the dimensions of the body segments. Each body segment was modelled as a frustrum of cone, whose dimension matched the body segment parameters (relative mass, density, and centroid) reported in the literature. The buoyancy torque was found to attain its peak value (13 Nm) in the middle of the recovery phase. Sensitivity tests revealed that the individual variability in the body segment parameters would make small effects (< 3 %) on the buoyancy torque. With this method, the effect of buoyant force on body-roll can be determined to a known degree of accuracy

A New Approach for Assessing Kinematics of Torso Twist in Baseball Batting: A Preliminary Report

The motions of segments involved in striking and throwing events are generally sequenced in a proximal-to-distal fashion (Putnam 1993). Welch et al. (1995) analyzed baseball batting using a rigid-body-link model with a two-segment torso, and indicated the importance that the lower torso starts rotation in the direction of pitcher before the upper torso, which, in turn, should start before the arm segments. Also, this sequential motion is considered to allow the kinetic link system to generate synergy between the musculature of the torso and upper extremity. Specifically, the upper torso is expected to have an important function to accelerate distal upper extremity and bat. However previous studies employed a two-segment torso model and the influence of the motions of the shoulder-girdles to the torso’s sequential action for twisting was ignored. In the present study, torso’s sequential twisting was analyzed with a three-segment torso model, and the kinematics of torso twist in baseball batting was evaluated

11C-Labeling of Indolealkylamine Alkaloids and the Comparative Study of Their Biodistributions

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Preservation of Glucose Metabolism in Caudate Region at the Terminal Stage of Late-Infantile Neuronal Ceroid-Lipofuscinosis

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Characteristics of Specific in Vivo Labeling of Neuroleptic Binding Sites with 3-[11C]Methylspiperone

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Absolute value measurement of ion-scale turbulence by two-dimensional phase contrast imaging in Large Helical Device

Absolute value measurements of turbulence amplitude in magnetically confined high-temperature plasmas can effectively explain turbulence-driven transport characteristics and their role in plasma confinements. Two-dimensional phase contrast imaging (2D-PCI) is a technique to evaluate the space-time spectrum of ion-scale electron density fluctuation. However, absolute value measurement of turbulence amplitude has not been conducted owing to the nonlinearity of the detector. In this study, the absolute measurement method proposed in the previous study is applied to turbulence measurement results in the large helical device. As a result, the localized turbulence amplitude at $n_e=1.5\times 10^{19}$m$^{-3}$ is approximately $3.5\times 10^{15}$m$^{-3}$, which is 0.02\% of the electron density. In addition, the evaluated poloidal wavenumber spectrum is almost consistent, within a certain error range, the spectrum being calculated using a nonlinear gyrokinetic simulation. This result is the first to the best of our knowledge to quantitatively evaluate turbulence amplitudes measured by 2D-PCI and compare with simulations

Correct quantum chemistry in a minimal basis from effective Hamiltonians

We describe how to create ab-initio effective Hamiltonians that qualitatively describe correct chemistry even when used with a minimal basis. The Hamiltonians are obtained by folding correlation down from a large parent basis into a small, or minimal, target basis, using the machinery of canonical transformations. We demonstrate the quality of these effective Hamiltonians to correctly capture a wide range of excited states in water, nitrogen, and ethylene, and to describe ground and excited state bond-breaking in nitrogen and the chromium dimer, all in small or minimal basis sets