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Average Coefficient (average + coefficient)
Selected AbstractsCompetitive ELISA studies of neural thread protein in urine in Alzheimer's diseaseJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 1 2007Susanna Levy Abstract A specific and reliable competitive affinity assay kit has been developed to quantitatively measure neural thread protein (NTP) in first morning urine samples. This assay, called the urine neural thread protein test (UNTP), is a competitive enzyme-linked immunosorbent assay (ELISA) format affinity assay using 32-well microtiter plates. The assay detects UNTP in the 10,60,µg/mL range (an improvement over earlier assays of 103 × ), is linear and more reproducible (average coefficient of variation [CV] 6.2% in precision studies). The utility of the assay has been demonstrated in urine samples from patients with Alzheimer's disease (AD) and controls (sensitivity of 90% and specificity of 91%). Test,retest assays of subjects with AD and controls were comparatively stable at intervals of 2 days to 4.5 years, which suggests that positive (elevated) or negative (normal) NTP levels do not fluctuate significantly over time with respect to the cutoff. J. Clin. Lab. Anal. 21:24,33, 2007. © 2007 Wiley-Liss, Inc. [source] The influence of oxygen on the friction and wear behaviour of a copper,steel couple under electric currentLUBRICATION SCIENCE, Issue 1 2004A. Bouchoucha Abstract The tribological behaviour of a copper,steel couple similar to those in electrified railways has been studied as a function of mechanical, electrical, and environmental parameters. The experimental results obtained in an oxygen atmosphere show that this factor has a major influence on the wear behaviour. While there was a reduction in the average coefficient of friction compared to in argon, under oxygen there was twice the wear found under air, and six times that found under argon. In the absence of an electric current, the nature of the wear was essentially mild adhesive. However, with an electric current at the interface, fluctuations, particularly at high intensities, were recorded in both the coefficient of friction and the electrical contact resistance, and there was severe wear. Discussion of the results is based on examination of the wear surfaces and analysis of the phenomena observed during sliding contact. [source] High-precision isotopic analysis of palmitoylcarnitine by liquid chromatography/electrospray ionization ion-trap tandem mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 22 2006ZengKui Guo Single quadrupole gas chromatography/mass spectrometry (GC/MS) has been widely used for isotopic analysis in metabolic investigations using stable isotopes as tracers. However, its inherent shortcomings prohibit it from broader use, including low isotopic precision and the need for chemical derivatization of the analyte. In order to improve isotopic detection power, liquid chromatography/electrospray ionization ion-trap tandem mass spectrometry (LC/ESI-itMS2) has been evaluated for its isotopic precision and chemical sensitivity for the analysis of [13C]palmitoylcarnitine. Over the enrichment range of 0.4,10 MPE (molar % excess), the isotopic response of LC/ESI-itMS2 to [13C]palmitoylcarnitine was linear (r,=,1.00) and the average isotopic precision (standard deviation, SD) was 0.11 MPE with an average coefficient of variation (CV) of 5.6%. At the lower end of isotopic enrichments (0.4,0.9 MPE), the isotopic precision was 0.05 MPE (CV,=,8%). Routine analysis of rat skeletal muscle [13C4]palmitoylcarnitine demonstrated an isotopic precision of 0.03 MPE for gastrocnemius (n,=,16) and of 0.02 MPE for tibialis anterior (n,=,16). The high precision enabled the detection of a small (0.08 MPE) but significant (P,=,0.01) difference in [13C4]palmitoylcarnitine enrichments between the two muscles, 0.51 MPE (CV,=,5.8%) and 0.43 MPE (CV,=,4.6%), respectively. Therefore, the system demonstrated an isotopic lower detection limit (LDL) of ,0.1 MPE (2 × SD) that has been impossible previously with other organic mass spectrometry instruments. LC/ESI-itMS2 systems have the potential to advance metabolic investigations using stable isotopes to a new level by significantly increasing the isotopic solving power. Copyright © 2006 John Wiley & Sons, Ltd. [source] Genetic diversity of dog breeds: within-breed diversity comparing genealogical and molecular dataANIMAL GENETICS, Issue 3 2009G. Leroy Summary The genetic diversity of 61 dog breeds raised in France was investigated. Genealogical analyses were performed on the pedigree file of the French kennel club. A total of 1514 dogs were also genotyped using 21 microsatellite markers. For animals born from 2001 to 2005, the average coefficient of inbreeding ranged from 0.2% to 8.8% and the effective number of ancestors ranged from 9 to 209, according to the breed. The mean value of heterozygosity was 0.62 over all breeds (range 0.37,0.77). At the breed level, few correlations were found between genealogical and molecular parameters. Kinship coefficients and individual similarity estimators were, however, significantly correlated, with the best mean correlation being found for the Lynch & Ritland estimator (r = 0.43). According to both approaches, it was concluded that special efforts should be made to maintain diversity for three breeds, namely the Berger des Pyrénées, Braque Saint-Germain and Bull Terrier. [source] Consanguineous marriages in Jordan: why is the rate changing with time?CLINICAL GENETICS, Issue 6 2005H Hamamy The objective of this study was to explore the secular trend in consanguinity in Jordan and the subtypes of consanguineous marriages that may be undergoing a change. A total of 1032 individuals attending a diabetic clinic in Amman were interviewed. The questionnaire provided information on consanguinity status and date of marriage among three generations: the persons interviewed, their parents, parents of their spouses and their offspring. Data on consanguinity status among 5401 marriages was obtained. Generations were named generation 1 for marriages contracted before 1950, generation 2 for marriages contracted between 1950 and 1979, and generation 3 for marriages contracted after 1980. For generations 1, 2, and 3, first-cousin marriages constituted 20.2, 28.5 and 19.5% of all marriages, respectively, while the subtype of paternal parallel first-cousin marriages constituted 75.6, 60.3 and 43.3% of all first-cousin marriages, respectively. The offspring of first-cousin parents were significantly more prone to marry their relatives than the offspring of non-consanguineous parents, with rates of first-cousin marriages among offspring of first-cousin parents and non-related parents constituting 25.3 and 17.1% of all marriages, respectively. For generations 1, 2 and 3, the average coefficient of inbreeding was 0.0135, 0.02 and 0.0142, respectively. In conclusion, first-cousin marriage rate among a representative population from Amman showed a significant decline among marriages contracted after 1980 compared to marriages contracted between 1950 and 1979, but not to marriages contracted before 1950. The proportion of paternal parallel first cousins among first-cousin marriages showed a steady decline from one generation to the next. [source] | ||||||||||