Due to its high activities in groundwater, the radionuclide 222Rn is a sensitive natural tracer to detect and quantify groundwater inflow into lakes, provided the comparatively low activities in the lakes can be measured accurately. Here we present a simple method for radon measurements in the low-level range down to 3 Bq m−3, appropriate for groundwater-influenced lakes, together with a concep...

OBJECTIVE The goal of this research was to compare side-to-side (STS) and end-to-side (ETS) anastomoses in a computer model of the arteriovenous fistula with computational fluid dynamic analysis. METHODS A matrix of 17 computer arteriovenous fistula models (SolidWorks, Dassault Systèmes, France) of artery-vein pairs (3-mm-diameter artery + 3-mm-diameter vein and 4-mm-diameter artery +6-mm-dia...

The pulmonary diffusing capacity for carbon monoxide was measured by single breath (DcoSB) and steady state (DcoSS) techniques in 48 patients with various pulmonary circulatory disorders and the results compared with the type of hemodynamic abnormality. Patients with pure inflow obstruction (primary pulmonary hypertension, recurrent pulmonary emboli) had the lowest Dco (mean DcoSB = 14.3 ml/min...

BACKGROUND The recently introduced automated cardiac flow measurement (ACM) technique provides a quick and an accurate automated calculation of stroke volume and cardiac output. This is obtained by spatio-temporal integration of digital Doppler velocity profile data. OBJECTIVE To evaluate the use of the ACM method in the non-invasive assessment of aortic regurgitant volume and per cent regurg...

Background: The recently introduced automated cardiac flow measurement (ACM) technique provides a quick and an accurate automated calculation of stroke volume and cardiac output. This is obtained by spatio-temporal integration of digital Doppler velocity profile data. Objective: To evaluate the use of the ACM method in the non-invasive assessment of aortic regurgitant volume and per cent regurg...

I present results from numerical simulations of gas dynamics outside luminous accretion disks in active galactic nuclei. The gas, gravitationally captured by a super massive black hole, can be driven away by the energy and momentum of the radiation emitted during black hole accretion. Assuming axisymmetry, I study how the mass accretion and outflow rates, and the flow dynamics respond to change...

Natural selection is presumed to be the driving force behind the occurrence of phenotypically and genetically divergent populations in sympatry within many north temperate freshwater fishes. If, however, these populations have different ancestral origins, history could also contribute to their divergence. We previously found evidence for the role of selection in the evolution of divergent outfl...

The aim of this study was to gain better understanding of the variable anatomical features of double inlet left ventricle hearts without cavopulmonary connection that would potentially facilitate favorable streaming. Thirty-nine post-mortem specimens of double inlet left ventricle without cavopulmonary connection were investigated. The focus was on anatomical characteristics that could influenc...

The aim of this study was to determine if reliable patient-specific wall shear stress (WSS) can be computed when diameter-based scaling laws are used to impose the boundary conditions for computational fluid dynamics. This study focused on mildly diseased human coronary bifurcations since they are predilection sites for atherosclerosis. Eight patients scheduled for percutaneous coronary interve...

BACKGROUND Historically, the primary hazard with liver surgery has been intraoperative blood loss. This led to the refinement of inflow and outflow occlusive techniques. The utility of the different methods of inflow and outflow techniques for hepatic surgery were reviewed. METHODS A search of the English literature (Medline, Embase, Cochrane library, Cochrane clinical trials registry, hand s...