• The dispersion of an indicator in a flowing liquid increases with time and with the distance travelled. The form of the dispersion and its rate of increase have only recently come to the attention of investigators. Poiseuille's model, parabolic flow, has been used as an approximate description of flow in the vascular system in spite of the fact that there are a priori reasons for expecting it...

Introduction. There is a problem with commonly accepted parameters for microcirculation. This problem is due to many used mathematical models. The aim of notes to reveal that hypothesis about stochasticity of microflow leads to the uniqueness of mathematical equations for passage throughout microcirculation. Thus stochasticity could be a motivation for the choice of parameters of microcirculati...

The system mean transit time (T,^) of the impulse response function describing contrast material transit through the coronary circulation was determined from serial digital angiographic images. The linearity, reproducibility, and relations with regional myocardial perfusion and conventional time-density curve parameters, time to peak concentration (TPC), and exponential washout rate (k) were as...

• In the usual procedure for determination of indicator dilution curves, the sensing or measuring device is placed at some distance from the sampling site. The fluid is transported by a sampling system, usually a cathe-ter, from the withdrawal site to the sensing point. This sampling system always introduces some distortion in the time-concentration curve, so that the recorded curve is not the ...

We compared the performance of SARS-CoV-2 neutralising antibody testing between 12 European laboratories involved in convalescent plasma trials. Raw titres differed almost 100-fold differences when blind-testing 15 samples. Calibration relation to reference reagent and standard curve obtained by a dilution series reduced inter-laboratory variability ca 10-fold. The harmonisation quantification ...

in this paper, we give some characterizations for legendre spherical, legendre normal and legendre rectifying curves in the 3-dimensional sasakian space. furthermore, we show that legendre spherical curves are also legendre normal curves. in particular, we prove that the inverse of curvature of a legendre rectifying curve is a non-constant linear function of the arclength parameter.

Load theory of attention proposes that distractor processing is reduced in tasks with high perceptual load that exhaust attentional capacity within task-relevant processing. In contrast, tasks of low perceptual load leave spare capacity that spills over, resulting in the perception of task-irrelevant, potentially distracting stimuli. Tsal and Benoni (2010) find that distractor response competit...

The selection of an external site for a radioisotope determination of cardiac output is discussed with respect to satisfying the analytical conditions of the Stewart-Hamilton dilution equation. Examples of both single-chamber and multichamber recording are illustrated, along with a discussion of the difficulties of curve calibration and extrapola. tion from multiple sites. The development of a ...

The selection of an external site for a radioisotope determination of cardiac output is discussed with respect to satisfying the analytical conditions of the Stewart-Hamilton dilution equation. Examples of both single-chamber and multichamber recording are illustrated, along with a discussion of the difficulties of curve calibration and extrapola. tion from multiple sites. The development of a ...

Aneurysmal dilatation of the left atrium occurs in mitral incompetence (Parsonnet, Bernstein, and Martland, 1946) and in mitral stenosis (Venner, 1954), and its presence may mask the underlying mitral lesion by modifying the left atrial pressure pulse (Fairley, 1961) and the indicator-dilution curve (Nixon and Snow, 1962). The purpose of this communication is to describe the important clinical,...