The distances between three or four radiopaque markers located on the left ventricular epicardial surface at the apex and in the region of the minor axes in 22 subjects showed close correlations with left ventricular chamber radii, length, volume and wall thickness determined from biplane angiograms over the range of stroke volume. The markers were previously placed during heart surgery. Regres...

A digital detector provides numerical information at each pixel. This value may be difficult to be interpreted quantitatively. In this paper, the main factors to be considered during physical interpretation are reviewed: beam-hardening effect, scattering diffusion, type of detector. Some of them induce degradation on the digital radiograph while others modify the nature of available information...

Background: Muscle fatigue is an important issue in neuromuscular rehabilitation. Better control of this phenomenon would result in better prevention of its consequent physiological damages.Objective: To provide a mathematical representation of muscle fatigue as a function of time.Methods: We conducted this study by combining the EMG-based estimation methods of muscle activation with the availa...

T4 lysozyme (T4L) is an important model system for investigating the relationship between protein structure and function. Despite being extensively studied, a reliable, quantitative activity assay for T4L has not been developed. Here, we present an improved T4L turbidity assay as well as an affinity-based T4L expression and purification protocol. This assay is designed for 96-well format and ut...

Distributions on classifications are met wherever we work with categorical variables. A vast investigation has been done in developing methods for statistical analysis of nominal variables (e.g. variables with simple classification), partially are solved also problems for ordered classifications and classifications with assigned numbers. In this paper we propose a general model which enables us...

Shaft vibrational frequency is a quantitative measurement of the rate of vibration (oscillation) of a shaft as expressed over a known unit of time. In the late 1970's a few individuals began working on developing a way to identify a quantitative measurement of shaft stiffness to be able to ensure a more accurate progression of stiffness through sets of golf clubs. Vibrational frequency became a...

− According to the realist interpretation, measurement is the estimation of numerical relations (or ratios) between magnitudes of a quantitative attribute and a unit. The history of scientific measurement, from antiquity to the present may be interpreted as revealing a progressive deepening in the understanding of this position. First, the concept of ratio was broadened to include ratios betwee...