6,611,040 research outputs found
Validation of a new spectrometer for noninvasive measurement of cardiac output
Acetylene is a blood-soluble gas and for many years its uptake rate during rebreathing tests has been used to calculate the flow rate of blood through the lungs (normally equal to cardiac output) as well as the volume of lung tissue. A new, portable, noninvasive instrument for cardiac output determination using the acetylene uptake method is described. The analyzer relies on nondispersive IR absorption spectroscopy as its principle of operation and is configured for extractive (side-stream) sampling. The instrument affords exceptionally fast (30 ms, 10%–90%, 90%–10%, at 500 mL min–1 flow rates), interference-free, simultaneous measurement of acetylene, sulfur hexafluoride (an insoluble reference gas used in the cardiac output calculation), and carbon dioxide (to determine alveolar ventilation), with good (typically ±2% full-scale) signal-to-noise ratios. Comparison tests with a mass spectrometer using serially diluted calibration gas samples gave excellent (R2>0.99) correlation for all three gases, validating the IR system's linearity and accuracy. A similar level of agreement between the devices also was observed during human subject C2H2 uptake tests (at rest and under incremental levels of exercise), with the instruments sampling a common extracted gas stream. Cardiac output measurements by both instruments were statistically equivalent from rest to 90% of maximal oxygen consumption; the physiological validity of the measurements was confirmed by the expected linear relationship between cardiac output and oxygen consumption, with both the slope and intercept in the published range. These results indicate that the portable, low-cost, rugged prototype analyzer discussed here is suitable for measuring cardiac output noninvasively in a point-of-care setting
Plant Remains from Shelby Mound (41CP71), Camp County, Texas
Nine lots of botanical samples collected during 1988 and 1992 excavations at the Shelby Mound site (41CP71) were submitted for identification prior to their eventual curation at Stephen F. Austin State University. Some botanical samples from these excavations have been previously reported. Excavations at Shelby Mound were conducted in a 10 x 10 ft. unit divided into four 5 x 5 ft. squares. Botanical samples were recovered using 1/4-inch screen. Shelby Mound, also known as the Tracy site and the Greasy Creek site, is a large Late Caddo village, community cemetery, and mound center. Most of the community cemetery at the site was destroyed by looters more than 30 years ago
Together Towards Improvement: a process for self-evaluation: special
"Increasingly, there is the realisation that if improvement in a school’s provision is to be
initiated and sustained effectively, then it is crucial that the culture of self-evaluation is
promoted and that the process of self-evaluation is embedded within a school’s way of
working.
These materials are but one of a range of resources that may be used to help foster that
culture and support the process of self-critical evaluation of current practices, with the aim
of improving the quality of the pupils’ experiences and the standards they achieve." - Page 3
A-H-S-T Community School District, Auditor of State's Report on Reaudit, For the Period July 1, 2002 through June 30, 2003
Community School District Audit Report - Reaudi
Review of Bombing the City: Civilian Accounts of the Air War in Britain and Japan, 1939-1945 by Aaron William Moore
Review of Bombing the City: Civilian Accounts of the Air War in Britain and Japan, 1939-1945 by Aaron William Moore
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