+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Modeling the isovolumic relaxation period

, : Modeling the isovolumic relaxation period. Catheterization & Cardiovascular Diagnosis 11(3): 255-268

The isovolumic relaxation period of the left ventricular pressure curve in man is assumed to be best represented by an exponential decay. To determine which model most closely approximates the empiric pressure data of isovolumic relaxation in man, several models were compared. They included linear, exponential with a zero mmHg pressure asymptote, exponential with a variable asymptote and 2nd-to 5th-order polynomials. In addition, 4 different methods of computing parameters of isovolumic relaxation by the exponential model with a variable asymptote were tested. The isovolumic relaxation period approximates an exponential, that the theoretic asymptote is variable, and that the Levenburg-Marquardt algorithm can be used efficiently to model this period.


PMID: 3893739

DOI: 10.1002/ccd.1810110305

Other references

Norton, J.M.; Low, J.M.; Klotz, M.G., 1996: The gene encoding ammonia monooxygenase subunit A exists in three nearly identical copies in Nitrosospira sp. NpAV. The gene encoding ammonia monooxygenase subunit A (AmoA) was found in three copies in the genome of the chemolithotrophic soil bacterium, Nitrosospira sp. NpAV. The open reading frame and flanking regions of the three copies were isolated from dig...

Palu, E.G.; Silva, A.B. da; Pasqual, M., 2004: In vitro callogenesis in anthers of Coffea arabica L. A protocol was developed for the in vitro regeneration of flower buds and anthers from coffee cultivars Acaia Cerrado and Rubi. The explants of Acaia Cerrado were in vitro-cultured on IC medium supplemented with 2,4-D (0, 1, 2 and 4 mg/litre) + ki...

Schafer, E.R.; Pew, J.C., 1942: The grinding of Engelmann Spruce for newsprint and magazine quality mechanical pulps. This report compares the grinding characteristics of Engelmann Spruce and White Spruce for newsprint and magazine quality pulps. KEYWORDS: Picea engelmanni pulp \ Picea glauca P.

Noelle, H., 1963: Influence of natural and artificial fever on nitrogen balance. Nitrogen balance studies for periods of 20, 36 and 61 days were carried out in 4 patients with various ailments. Exact consumption of food was realized by giving Biosorbin (Protein 19%, fat 12%, carbohydrate 61%) as well as minerals and vitamins b...

Holtrop, M.E.; King, G.J., 1977: The ultrastructure of the osteoclast and its functional implications. Recent findings on the ultrastructure of the osteoclast indicate that special attention should be given to the ruffled border, clear zone, and the vacuoles and vesicles of the cell and their significance for the mechanism of breakdown of bone matr...

King, L.; Tulandi, T.; Whitley, R.; Constantinescu, T.; Ells, C.; Zelkowitz, P., 2015: What's the message? A content analysis of newspaper articles about assisted reproductive technology from 2005 to 2011. Infertility and its treatment is the subject of considerable media coverage. In order to evaluate the representation of assisted reproductive technology (ART) in the popular media, we conducted a content analysis of North American newspaper articl...

Zapata Solari, C., 2017: The Revista de Gastroenterologia del Peru and its perspectives for the present year. Revista de Gastroenterologia del Peru 37(1): 7-8

Ricci, M., 1969: Recent acquisitions on the immunobiological properties of reagins. Folia Allergologica 16(2): 113-119

Halford, S.E.; Lennette, D.A.; Schlesinger, M.J., 1972: A mutationally altered alkaline phosphatase from Escherichia coli. II. Structural and catalytic properties of the activated enzyme. Journal of Biological Chemistry 247(7): 2095-2101

Jan, M.; Sattar, A.; Mehmood, F.; Ali, Y., 2000: Chemical and technological evaluation of fortified wheat bread (Chapati) with oilseed flours. Wheat chapattis (unleavened bread) were prepared after fortifying wheat flour with different oilseed flours at 5 and 10%. Chapattis were evaluated for nutritive value and for acceptability by sensory evaluation. At the 5 and 10% fortification leve...