A simple theoretical approach is presented for estimating vascular distensibility of small blood vessels from noninvasively obtained pressure-flow data in the hand and forearm of human subjects. To the extent that Poiseuille's law applies to blood flow in these vascular beds, conductance (the reciprocal of vascular resistance) can be calculated from these data as the ratio of blood flow to mean...

BACKGROUND Qualitative research is frequently context bound, lacks generalizability, and is limited in scope. OBJECTIVES The purpose of this article was to describe a method, theoretical coalescence, that provides a strategy for analyzing complex, high-level concepts and for developing generalizable theory. Theoretical coalescence is a method of theoretical expansion, inductive inquiry, of th...

We discuss a formal development for the certification of Newton’s method. We address several issues encountered in the formal study of numerical algorithms: developing the necessary libraries for our proofs, adapting paper proofs to suit the features of a proof assistant, and designing new proofs based on the existing ones to deal with optimizations of the method. We start from Kantorovitch’s t...

The concept of the theory of continuous groups of transformations has attracted the attention of applied mathematicians and engineers to solve many physical problems in the engineering sciences. Three applications are presented in this paper. The first one is the problem of time-dependent vertical temperature distribution in a stagnant lake. Two cases have been considered for the forms of the w...

Bioanalytical method development largely depends on the experience and the preference of the developer. Mathematical models could help in selecting the proper conditions to develop a selective and robust method, using liquid chromatography, liquid-liquid extraction, solid phase extraction and protein precipitation. This paper reviews the literature providing relevant equations and algorithms to...

In this work we propose a new method for solving the blind source separation (BSS) problem using a support vector machine (SVM) workbench. Thus, we provide an introduction to SVM-ICA, a theoretical approach to unsupervised learning based on learning machines, which has frequently been proposed for classification and regression tasks. The key idea is to construct a Lagrange function from both th...

We propose a torque method for the theoretical determination of the magnetocrystalline anisotropy ~MCA! energy for systems with uniaxial symmetry. While the dependence of the total energy on the angle between the magnetization and the normal axis (u) can be expressed as E(u)5E01K2sin (u)1K4sin (u), we show that the MCA energy @defined as EMCA5E(u590°)2E(u50°)5K21K4# can be easily evaluated thro...

Background: To improve the quality of education, evaluating clinical and theoretical teaching and giving feedbacks to the teachers to obviate the drawbacks is of important value. Evaluation results are reliable if the gathered data are correct and precise and it can be achieved only if there are precise tools to gather data. This study was performed to prepare valid forms to evaluate theoretica...

This article documents two facts that are provocative in juxtaposition. First: There is multidecade durability of theory controversies in psychology, demonstrated here in the subdisciplines of cognitive and social psychology. Second: There is a much greater frequency of Nobel science awards for contributions to method than for contributions to theory, shown here in an analysis of the last two d...