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Dynamic activity, definition

One endurance-related measure uses either the number of repetitions that can be performed at 20, 25, or 50% of maximum peak torque or force. The units used to reflect endurance in this case are number of repetitions at a specified torque or force level. One difficulty with this definition has been described previously, that is, the issue of relative vs. absolute muscle endurance. Rothstein and Rose [1982] demonstrated that elderly subjects with selected muscle fiber type atrophy were able to maintain 50% of their peak torque longer than young subjects. However, if a high force level is required to perform the task, then the younger subject would have more endurance in that particular activity [Rothstein, 1982]. Another difficulty is that the repetition method can be used only for dynamic activities. If isometric activities are involved, then the time an activity can be sustained at a specified force or torque level is measured. Why have different units of endurance Time could be used in both cases. Furthermore, the issue of absolute vs. relative muscle endurance becomes irrelevant if the demands of the task are measured. [Pg.1257]

Electrochemical cells may be used in either active or passive modes, depending on whether or not a signal, typically a current or voltage, must be actively appHed to the cell in order to evoke an analytically usehil response. Electroanalytical techniques have also been divided into two broad categories, static and dynamic, depending on whether or not current dows in the external circuit (1). In the static case, the system is assumed to be at equilibrium. The term dynamic indicates that the system has been disturbed and is not at equilibrium when the measurement is made. These definitions are often inappropriate because active measurements can be made that hardly disturb the system and passive measurements can be made on systems that are far from equilibrium. The terms static and dynamic also imply some sort of artificial time constraints on the measurement. Active and passive are terms that nonelectrochemists seem to understand more readily than static and dynamic. [Pg.49]

In this chapter, a short introduction to DFT and to its implementation in the so-called ab initio molecular dynamics (AIMD) method will be given first. Then, focusing mainly on our own work, applications of DFT to such fields as the definition of structure-activity relationships (SAR) of bioactive compounds, the interpretation of the mechanism of enzyme-catalyzed reactions, and the study of the physicochemical properties of transition metal complexes will be reviewed. Where possible, a case study will be examined, and other applications will be described in less detail. [Pg.42]

When the isoconversional method is applied to the set of dynamic runs, an activation energy lying in the 69-73 kJ mol-1 range is obtained, without any definite trend with conversion. The value is very close to the one reported by Montserrat and Malek (1993) using this method again, this is an apparent value without any physical meaning. [Pg.175]

Hamiltonian proposed by Muller and Plesset gives rise to a very successful and efficient method to treat electron correlation effects in systems that can be described by a single reference wave function. However, for a multireference wave function the Moller-Plesset division can no longer be made and an alternative choice of B(0> is needed. One such scheme is the Complete Active Space See-ond-Order Perturbation Theory (CASPT2) developed by Anderson and Roos [3, 4], We will briefly resume the most important definitions of the theory one is referred to the original articles for a more extensive description of the method. The reference wave function is a CASSCF wave function that accounts for the largest part of the non-dynamical electron correlation. The zeroth-order Hamiltonian is defined as follows and reduces to the Moller-Plesset operator in the limit of zero active orbitals ... [Pg.230]

What happens to the other proteins that are adsorbed on foreign materials We know that many proteins are quite firmly bound to the surface and that it is difficult to wash some of these off. We also know that many of these proteins have definite biological function other than merely osmotic activity. We also know that the strength of these adsorption forces varies with different proteins, but apparently a dynamic state exists with proteins being adsorbed, desorbed, and new proteins adsorbed. It would seem quite coincidental if Hageman factor were the only one of these proteins that altered its biological function as a result of this adsorption and desorption. It seems quite obvious that materials which are compatible with blood must not appreciably alter any of the vital blood proteins. [Pg.181]


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Activity, definition

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