Search

Your search keyword '"Cornejo, Ivan"' showing total 24 results
Start Over Author "Cornejo, Ivan"
24 results on '"Cornejo, Ivan"'

14. Simulation of Flow Patterns in Particulate Filters with Various Viscous Models

Author

Mesquida, Ileana M. Vega, Cornejo, Ivan, Nikrityuk, Petr, and Hayes, Robert E.

Abstract

There has been an increased focus on using gasoline direct injection engines operating at the stoichiometric point due to their potential to improve fuel economy. Nonetheless, particulate matter emitted by gasoline vehicles negatively affect human health. Gasoline particulate filters are the most promising technology in the reduction of particulate matter emissions along with fuel efficiency. Depending on the particle’s size, its deposition and trajectory highly depend on flow pattern; however, the flow regime within gasoline particulate filters is still yet to be solved. The present investigation uses a representation of a gasoline particulate filter to demonstrate the effects of turbulence in the flow behaviour therein. These effects are analysed utilising different Reynolds-average-Navier-Stokes models and the laminar model with inflow velocities and filter wall permeability. The results demonstrate that turbulence significantly modifies flow pattern within the channels and porous wall as well as the pressure drop.

Published
2024
Full Text
View/download PDF

24. Influence of Fluid Volume Variations on the Calculated Value of the Left Ventricular Mass Measured by Echocardiogram in Patients Submitted to Hemodialysis.

Author

Martin, Luis Cuadrado, Barretti, Pasqual, Cornejo, Ivan Velasco, Felipe, Maria Justina, Forti, Adjair Humberto, Matsubara, Beatriz Bojikian, Okoshi, Katashi, Padovani, Carlos Roberto, Teixeira-Caramori, Jacqueline, Ferreira Tucci, Paulo José, and da Silva Franco, Roberto Jorge

Subjects
TUMORS, HEART diseases, ECHOCARDIOGRAPHY, HEMODIALYSIS patients
Abstract

The left ventricular mass (LVM) measurement is of major importance for renal patients, as ventricular hypertrophy is an important prognostic index. The echocardiogram of the ventricular mass is larger before than it is after hemodialysis, which can confuse data interpretation. The aim of this work is to study the influence of alterations in fluid volume on the variations in measurements of ventricular mass observed during the course of a hemodialysis. Sixteen patients with chronic renal insufficiency in hemodialysis were evaluated at the Dialysis Unit of the University Hospital—UNESP, Botucatu, São Paulo State. The left ventricular mass was calculated from echocardiograms taken before and after hemodialysis and simultaneous ultra-filtration (12 patients: UF GROUP) and before and after hemodialysis isovolemic phase with sequential ultra-filtration (10 patients: ISO GROUP). Six of these patients were submitted to measurements of left ventricular mass before and after hemodialysis in both isovolemic and simultaneous ultra-filtration procedures. In the UF group, there was significant reduction in the following parameters before and after dialysis: diastolic diameter from 54.0 ± 6.0 mm to 45.6 ± 7.6 mm; left ventricular mass from 342 ± 114 g to 265 ± 117 g; and its respective index (IMVE) from 214 ± 68 g/m2 to 168 ± 71 g/m2. The ISO group showed no statistically significant variation. The behavior of the variables of six patients submitted to both observations confirm these results. In conclusion, the variations in echocardiogram measurements of the left ventricular mass relating to hemodialysis appear to be induced by alterations of the volemic condition. [ABSTRACT FROM AUTHOR]

Published
2003
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results