Portable battery-driven oxygen concentrators provide an alternative to the use of oxygen cylinders for treatment of hypoxemia during field anesthesia. The aim of this study was to evaluate the use of the EverGo Portable Oxygen Concentrator (Respironics, Murrysville, Pennsylvania 15668, USA) with pulse-dose delivery for improvement of arterial oxygenation during anesthesia of wildlife. This conc...

We present dimensionless effective transport coefficients (formation factors) for arrays of cylinders of various orientation distributions, namely, cylinders randomly positioned and oriented with their axes parallel to a line, parallel to a plane, or in the three-dimensional space with no preferred orientation. Both cases of conducting cylinders dispersed in a nonconducting matrix and nonconduc...

BACKGROUND Expired gas (exhalome) analysis of ventilated critical ill patients can be used for drug monitoring and biomarker diagnostics. However, it remains unclear to what extent volatile organic compounds are present in gases from intensive care ventilators, gas cylinders, central hospital gas supplies, and ambient air. We therefore systematically evaluated background volatiles in inspired g...

Recently, Guibas et al. 10 studied deformable necklaces – flexible chains of balls, called beads, in which only adjacent balls can intersect. In this paper, we investigate the problem of covering a necklace by cylinders. We consider several problems under different optimization criteria. We show that optimal cylindrical cover of a necklace with n beads in R by k cylinders can be computed in pol...

Introduction Several MR methods require a mathematical model of microvasculature to extract physiological parameters such as blood volume fraction (BVf), vessel size index (VSI) and blood oxygen saturation. In the case of BVf and VSI, MR estimates obtained in healthy and tumoral tissues – although well correlated with histology – seemed too large [1]. As tumoral development can strongly alter t...

Laminar natural convection from an array of horizontal isothermal cylinders confined between two vertical walls, at low Rayleigh numbers, is investigated by theoretical and numerical methods. The height of the walls is kept constant, however, number of the cylinders and their spacing, the distance between the walls and Rayleigh number have been varied. The optimal spacing (confining walls) and ...

Oxygen tension plays an important role in regulating various cellular functions in both normal physiology and disease states. Therefore, drug testing using conventional in vitro cell models under normoxia often possesses limited prediction capability. A traditional method of setting an oxygen tension in a liquid medium is by saturating it with a gas mixture at the desired level of oxygen, which...

In patients prescribed long-term oxygen therapy (LTOT), compliance is often poor. Both patient- and treatment-related factors seem to be involved. As a base for improvements in LTOT, the characteristics and complaints of LTOT patients were investigated. A survey was set up in a random sample of clients of the largest oxygen company in the Netherlands. Patients were selected if they were > or = ...

The stability of viscous flow between rotating cylinders in the presence of a constant axial magnetic field is considered. The boundary conditions for general conductivities are examined. It is proved that the Principle of Exchange of Stabilities holds at zero magnetic Prandtl number, for all Chandrasekhar numbers, when the cylinders rotate in the same direction, the circulation decreases outwa...