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Ken R. Lodewyk

dimensions from the Five-Factor Model (e.g., changing neuroticism to emotionality) while adding another dimension called honesty-humility (H) ( Ashton & Lee, 2007 ). Extensive research using the HEXACO in various cultures, languages, and age levels (e.g.,  Ashton & Lee, 2007 ; Lee & Ashton, 2004 ) has

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Mont Hubbard, Michael Kallay and Payam Rowhani

We have developed a mathematical model and computer simulation of three-dimensional bobsled turning. It is based on accurate descriptions of existing or hypothetical tracks and on dynamic equations of motion including gravitational, normal, lift, drag, ice friction, and steering forces. The three-dimensional track surface model uses cubic spline geometric modeling and approximation techniques. The position of the sled on the track is specified by the two variables α and β in the along-track and cross-track directions, differential equations for which govern the possible motions of the sled. The model can be used for studies involving (a) track design, (b) calculation of optimal driver control strategies, and (c) as the basis for a real-time bobsled simulator. It can provide detailed quantitative information (e.g., splits for individual turns) that is not available in runs at actual tracks. The model also allows for comparison of driver performance with the numerically computed optimum performance, and for safe experimentation with risky driving strategies.

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Onno G. Meijer, Yakov M. Kots and V. Reggie Edgerton

In 1963, an article on “Tonus” (tone), written by Nikolai A. Bernstein and Yakov M. Kots. appeared in the second edition of the Bols'aja Medicinskaja Enciclopedija [Grand Medical Encyclopedia]. The paper is now published for the first time in the English language, with Mark L. Latash as translator. In accordance with then contemporary neurophysiology and neuropsychology, the paper presented “tone” as a graded phenomenon (as opposed to all-or-none), serving to prepare the segmental level for phasic contractions. Influenced by Granit and Matthews, the authors proposed that the suprasegmental level controls the threshold and the slope of the stretch reflex. In their introduction to the present edition, the editors understand this proposal in the context of low-dimensional control, that is. control in terms of one or a few variables (as opposed to central commands specifying all the details). Selected episodes from the history of low dimensional control and its logical counterpart, spinal intelligence, are used to illustrate how difficult these ideas were to accept. As so often in new scientific developments, confusion was the rule, and in this respect the paper on “Tonus” is no exception. In the epilogue, Kots gives his personal memories of the context in which the paper was written. At the time, he was working on “equitonometry” (equitonometric), measuring tonic balance with gravity eliminated. Results of equitonometric research quite naturally led to the idea that suprasegmental centers control the threshold and the slope of me tonic stretch reflex. As Kots remembers, that was “no big deal.”

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Elisa S. Arch, Sarah Colón and James G. Richards

motion. 5 – 7 While this method provides a gross measure of overall bra motion, breasts consist of nonuniform, soft-tissue masses that likely move in complex 3-dimensional patterns. Thus, a single reference point on the nipple may not accurately capture motion that occurs in all regions of the breast. A

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Steven J. Obst, Lee Barber, Ashton Miller and Rod S. Barrett

.7 Hashizume et al 6 , c 3D MRI     35   41 41   40   Hashizume et al 6 , c 2D MRI     46   49 53   56   Manal et al 5 , d 2DUS 34.6   35.6   36.4 36.9   35.9   Clarke et al 7 , e 3D MRI     50.5   51.5 50     53 Current study f 3DUS     41.0 42.0 43.2   46.0   48.8 Abbreviations: 2D = 2-dimensional; 3D = 3

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Mary M. Rodgers, Srinivas Tummarakota and Junghsen Lieh

A three-dimensional (3-D) inverse dynamic model of wheelchair propulsion was developed using the Newton-Euler method based on body coordinate systems. With this model, the arm was assumed to be three rigid segments (hand, forearm, and upper arm) connected by the wrist, elbow, and shoulder joints. A symbolic method was adopted to generate the equations of motion. The model was used to compute the joint forces and moments based on the inputs obtained from a 3-D motion analysis system, which included an instrumented wheelchair, video cameras, and a data acquisition system. The linear displacements of markers placed on the joints were measured and differentiated to obtain their velocities and accelerations. Three-dimensional contact forces and moments from hand to handrim were measured and used to calculate joint forces and moments of the segments.

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Yongwoo Lee, Wonjae Choi, Kyeongjin Lee, Changho Song and Seungwon Lee

). Gaming systems based on virtual reality are potentially useful for technologies that allow users to synchronize their movements with the avatar on the screen ( Saposnik et al., 2010 ). Computer-generated three-dimensional environments create an atmosphere that is more realistic than two dimensions. A

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Brad W. Willis, Katie Hocker, Swithin Razu, Aaron D. Gray, Marjorie Skubic, Seth L. Sherman, Samantha Kurkowski and Trent M. Guess

reinjury and demonstrate increased rates of knee pain and prevalence of osteoarthritis. 1 – 4 Investigations into preventive screening techniques monitoring ACL injury risk factors aimed at mitigating female injury rates are warranted. 1 , 2 The use of 3-dimensional marker-based motion capture systems in

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Anna Bjerkefors, Johanna S. Rosén, Olga Tarassova and Anton Arndt

the test (n = 6). Three dimensional kinematic data were recorded using a 12-camera optoelectronic system (Oqus4; Qualisys AB, Gothenburg, Sweden) at a sampling frequency of 150 Hz. Between 39 and 64 reflective markers (12 mm diameter) were placed on various anatomical landmarks of the participants to

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Alexander W. Hooke, Sohit Karol, Jaebum Park, Yoon Hyuk Kim and Jae Kun Shim

The purpose of this study was to investigate central nervous system (CNS) strategies for controlling multifinger forces during a circle-drawing task. Subjects drew 30 concentric, discontinuous clockwise and counter clockwise circles, at self and experimenter-set paces. The three-dimensional trajectory of the pen’s center of mass and the three-dimensional forces and moments of force at each contact between the hand and the pen were recorded. Uncontrolled Manifold Analysis was used to quantify the synergies between pen-hand contact forces in radial, tangential and vertical directions. Results showed that synergies in the radial and tangential components were significantly stronger than in the vertical component. Synergies in the clockwise direction were significantly stronger than the counterclockwise direction in the radial and vertical components. Pace was found to be insignificant under any condition.