This paper discusses the role of knee positioning and range-of- motion on the closed-stance forehand tennis swing. The analyses of tennis swing mechanics were performed using a computer model comprised of a full-body model of a human and an inertial model of a racket. The model was driven by subject forehand swings (16 female college-level subjects) recorded with a high-speed digital motion ana...

OBJECTIVE This article aims to analyze the difference in stresses generated in the bracket-cement-tooth system by means of a peel load in single and double-mesh bracket bases using a three-dimensional finite element computer model. MATERIAL AND METHODS A three-dimensional finite element model of the bracket-cement-tooth system was constructed and consisted of 40,536 bonds and 49,201 finite el...

Tensile bond strength and bond failure location were evaluated in vitro for two types of aesthetic brackets (non-silanated ceramic, polycarbonate) and one stainless steel bracket, using bovine teeth as the substrate and diacrylate resin as the adhesive. The results show that metallic bracket had the highest bond strength (13.21 N) followed by the new plastic bracket (12.01 N), which does not re...

The symplectic and Poisson structures on reduced phase spaces are reviewed, including the symplectic structure on coadjoint orbits of a Lie group and the Lie-Poisson structure on the dual of a Lie algebra. These results are applied to plasma physics. We show in three steps how the Maxwell-Vlasov equations for a collisionless plasma can be written in Hamiltonian form relative to a certain Poisso...

Gene rearrangements within the process of gene assembly in ciliates can be represented using a 4-regular graph. Based on this observation, Burns et al. [Discrete Appl. Math., 2013] propose a graph polynomial abstracting basic features of the assembly process, like the number of segments excised. We show that this assembly polynomial is essentially (i) a single variable case of the transition po...

statement of problem: bracket de-bonding during initial orthodontic archwire placement immediately after bracket set up or following re-bonding a single bracket can be a clinical concern. purpose: the aim of this in vitro study was to assess the effect of time on the shear bond strength of a no-mix orthodontic composite adhesive. materials and methods: seventy freshly extracted human upper firs...

We study the quantization of Chern-Simons theory with group G coupled to dynamical sources. We first study the dynamics of Chern-Simons sources in the Hamiltonian framework. The gauge group of this system is reduced to the Cartan subgroup of G. We show that the Dirac bracket between the basic dynamical variables can be expressed in term of dynamical r−matrix of rational type. We then couple min...

We form a new 'blended' data set of sea level anomaly (SLA) fields by combining gridded daily fields derived from altimeter data with coastal tide gauge data. Within approximately 55-70 km of the coast, the altimeter data are discarded and replaced by a linear interpolation between the tide gauge and remaining offshore altimeter data. To create a common reference height for altimeter and tide g...

The Global Positioning System, GPS technology has been widely used in positioning and attitude determination. It is well known that the accuracy, availability and reliability of the positioning results are heavily dependent on the number and geometric distribution of tracked GPS satellites. Because of this limitation, in some situations, such as in urban canyons, underground space or inside of ...

BACKGROUND Fixed orthodontic mechanotherapy is associated with friction between the bracket - wire - ligature interfaces during the sliding mechanics. A sound knowledge of the various factors affecting the magnitude of friction is of paramount importance. The present study was done to analyze and compare the frictional forces generated by a new ceramic (Clarity Advanced) bracket with the conven...