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Various Measurements (various + measurement)
Selected AbstractsRight Ventricular Function Assessment: Comparison of Geometric and Visual Method to Short-Axis Slice Summation MethodECHOCARDIOGRAPHY, Issue 10 2007Daniel Drake M.D. Background: Short-axis summation (SAS) method applied for right ventricular (RV) volumes and right ventricular ejection fraction (RVEF) measurement with cardiac MRI is time consuming and cumbersome to use. A simplified RVEF measurement is desirable. We compare two such methods, a simplified ellipsoid geometric method (GM) and visual estimate, to the SAS method to determine their accuracy and reproducibility. Methods: Forty patients undergoing cine cardiac MRI scan were enrolled. The images acquired were analyzed by the SAS method, the GM (area and length measurement from two orthogonal planes) and visual estimate. RVEF was calculated using all three methods and RV volumes using the SAS and GM. Bland,Altman analysis was applied to test the agreement between the various measurements. Results: Mean RVEF was 49 ± 12% measured by SAS method, 54 ± 12% by the GM, and 49 ± 11% by visual estimate. There were similar bias and limits of agreement between the visual estimate and the GM compared to SAS. The interobserver variability showed a bias close to zero with limits of agreement within ±10% absolute increments of RVEF in 35 of the patients. The RV end-diastolic volume by GM showed wider limits of agreement. The RV end-systolic volume by GM was underestimated by around 10 ml compared to SAS. Conclusion: Both the visual estimate and the GM had similar bias and limits of agreement when compared to SAS. Though the end-systolic measurement is somewhat underestimated, the geometric method may be useful for serial volume measurements. [source] Microflow Vessel Improving Reproducibility and Sensitivity of Electrochemical MeasurementsELECTROANALYSIS, Issue 23 2008Jan Krejci Abstract A new microflow system was designed and developed for electrochemical measurements. The electrochemical electrodes prepared using thick film technology were used in this arrangement. Results of various measurements such as simple amperometric measurement on the example of H2O2 detection, measurement with glucose oxidase (GOx) biosensor, soluble enzyme activity measurement etc. carried out using this system are reported. It was observed that the sensitivity and reproducibility of the electrochemical measurements is improved significantly. The new device performance was proved on H2O2 detection, activity of GOx measurement and heavy metals detection (measured concentration range: H2O2 10,9 to 10,1,M, glucose 10,6 to 10,2,M, activity of GOx 10,1 to 102,IU, heavy metals (Cu, Pb) 10,4 to 10,3,M). The microflow insert greatly reduces the overall size of the electrolyte vessel and measurements with sample quantity as low as 2,mL can be accomplished. [source] Performance of block-coded land mobile satellite systemsINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 3 2008Chang-Ming Lee Abstract Although various measurements have indicated that mobile satellite channels are not memoryless, most related coded system performance analysis assumes perfect interleaving is in place so that the effect of channel memory can be completely ignored. This paper presents a systematic method to accurately and efficiently predict the performance of errors-and-erasures or errors-only decoders for block-coded systems in general mobile satellite channels. Numerical results are provided to validate our analytic results. Copyright © 2008 John Wiley & Sons, Ltd. [source] Milk Fat Globule EGF Factor 8 Attenuates Sepsis-Induced Apoptosis and Organ Injury in Alcohol-Intoxicated RatsALCOHOLISM, Issue 9 2010Rongqian Wu Background:, Despite advances in our understanding of excessive alcohol-intake-related tissue injury and modernization of the management of septic patients, high morbidity and mortality caused by infectious diseases in alcohol abusers remain a prominent challenge. Our previous studies have shown that milk fat globule epidermal growth factor-factor VIII (MFG-E8), a protein required to opsonize apoptotic cells for phagocytosis, is protective in inflammation. However, it remains unknown whether MFG-E8 ameliorates sepsis-induced apoptosis and organ injury in alcohol-intoxicated rats. The purpose of this study was to determine whether recombinant murine MFG-E8 (rmMFG-E8) attenuates organ injury after acute alcohol exposure and subsequent sepsis. Methods:, Acute alcohol intoxication was induced in male adult rats by a bolus injection of intravenous alcohol at 1.75 g/kg BW, followed by an intravenous infusion of 300 mg/kg BW/h of alcohol for 10 hours. Sepsis was induced at the end of 10-hour alcohol infusion by cecal ligation and puncture (CLP). rmMFG-E8 or vehicle (normal saline) was administered intravenously 3 times (i.e., at the beginning of alcohol injection, the beginning of CLP, and 10 hours post-CLP) at a dose of 20 ,g/kg BW each. Blood and tissue samples were collected 20 hours after CLP in alcoholic animals for various measurements. Results:, Acute alcohol exposure per se did not affect the production of MFG-E8; however, it primed the animal and enhanced sepsis-induced MFG-E8 downregulation in the spleen. Administration of rmMFG-E8 reduces alcohol/sepsis-induced apoptosis in the spleen, lungs, and liver. In addition, administration of rmMFG-E8 after alcohol exposure and subsequent sepsis decreases circulating levels of TNF-, and interleukin-6 and attenuates organ injury. Conclusions:, rmMFG-E8 attenuates sepsis-induced apoptosis and organ injury in alcohol-intoxicated rats. [source] Body composition and its components in preterm and term newborns: A cross-sectional, multimodal investigationAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2010Irfan Ahmad A prospective, cross-sectional, observational study in preterm and term infants was performed to compare multimodal measurements of body composition, namely, limb ultrasound, bone quantitative ultrasound, and dual X-ray absorptiometry (DXA). One hundred and two preterm and term infants appropriate for gestational age were enrolled from the newborn nursery and neonatal intensive care unit. Infants were included when they were medically stable, in an open crib, on full enteral feeds and within 1 week of anticipated discharge. Correlations among the various measurements of body composition were performed using standard techniques. A comparison between preterm infant (born at 28,32 weeks) reaching term to term-born infants was performed. Limb ultrasound estimates of cross-sectional areas of lean and fat tissue in a region of tissue (i.e., the leg) were remarkably correlated with regional and whole-body estimates of fat-free mass and fat obtained from DXA suggesting the potential usefulness of muscle ultrasound as an investigative tool for studying aspects of body composition in this fragile population. There was a weak but significant correlation between quantitative ultrasound measurements of bone strength and DXA-derived bone mineral density (BMD). Preterm infants reaching term had significantly lower body weight, length, head circumference, muscle and fat cross-sectional area, bone speed of sound, whole-body and regional lean body mass, fat mass, and BMD compared to term-born infants. Current postnatal care and nutritional support in preterm infants is still unable to match the in-utero environment for optimal growth and bone development. The use of relatively simple bedside, noninvasive body composition measurements may assist in understanding how changes in different components of body composition early in life affect later growth and development. Am. J. Hum. Biol. 2010. © 2009 Wiley-Liss, Inc. [source] | ||||||||||