Analysis of Cathode Sampling and Analytical Variance of Electrowon Copper

2008 ◽  
pp. 74-74-11
Author(s):  
JT Kline
Keyword(s):  
Analytical Variance

Effect of storage on measurement of ionized calcium in serum of uremic patients.

1985 ◽  
Vol 31 (2) ◽  
pp. 287-289 ◽  
Author(s):  
N I Nikolakakis ◽  
A M De Francisco ◽  
R S Rodger ◽  
E Gaiger ◽  
T H Goodship ◽  
...  
Keyword(s):  
Whole Blood ◽  
Room Temperature ◽  
Ionized Calcium ◽  
Measured Concentration ◽  
Analytical Variance ◽  
Serum Ionized Calcium ◽  
Uremic Patients ◽  
Serum Storage

Abstract We studied, in 70 acidotic and non-acidotic uremic patients, the analytical variance in serum ionized calcium as related to duration and temperature of storage. Storage of serum or whole blood at 4 degrees C for as long as 6 h did not significantly alter the measured concentration of ionized calcium in the serum. Storage at room temperature for 6 h, or longer at 4 degrees C or -20 degrees C, resulted in inaccuracies in 39 to 79% of the samples of serum and in 38 to 92% of the samples of whole blood. These errors were not negated by correcting the values for ionized calcium to a pH of 7.40. Indeed, corrected values for calcium were even more unreliable in acidotic patients. We conclude that samples from uremic patients should be analyzed for ionized calcium within 2 h, or within 6 h if stored at 4 degrees C.

EFFECTS OF REPRODUCTIVE STAGE, SEX, AND GONADAL HORMONES ON HEXOSAMINE AND PROTEIN LEVELS OF AVIAN AND BOVINE SERA

1962 ◽  
Vol 40 (1) ◽  
pp. 639-651 ◽  
Author(s):  
D. L. Grant ◽  
P. A. Anastassiadis
Keyword(s):  
Gonadal Hormones ◽  
Reproductive Stage ◽  
Moderate Increase ◽  
Protein Ratio ◽  
Protein Levels ◽  
Analytical Variance ◽  
Hexosamine Content

The levels of avian and bovine sera were determined for a number of animals of both sexes and different reproductive stages. The contents of both hexosamine and protein were higher in bovine than in avian serum. Maturation brought a large increase of the serum hexosamine in the female fowl and a small increase in the cow. Pregnancy brought a moderate increase of the hexosamine level in the cow. The hexosamine: protein ratio was smaller and more constant in the bovine than in the avian serum. The variances of the serum hexosamine and protein determinations were partitioned into analytical and biological variance and the analytical variance of hexosamine determination was partitioned into hydrolytic and colorimetric variance. The biological variance was much larger than the analytical, and for the determination of hexosamine the colorimetric variance was larger than the hydrolytic.In another study the effect o gonadal hormones on the level of serum hexosamine and on the value of hexosamine: protein ratio in the fowl was investigated by two experiments with immature pullets. Administration of estrogen increased the hexosamine content of serum and decreased the hexosamine: protein ratio. There were indications that the effect of estrogen on serum hexosamine was enhanced by androgen and was depressed by androgen plus progesterone.

Sampling dried figs for aflatoxin – Part 1: variability associated with sampling, sample preparation, and analysis

2017 ◽  
Vol 10 (1) ◽  
pp. 31-40 ◽  
Author(s):  
H. Ozer ◽  
H.I. Oktay Basegmez ◽  
T.B. Whitaker ◽  
A.B. Slate ◽  
F.G. Giesbrecht
Keyword(s):  
Sample Preparation ◽  
Test Procedure ◽  
Portion Size ◽  
Total Variance ◽  
Sampling Variance ◽  
Regression Equations ◽  
Sampling Step ◽  
Test Portion ◽  
Analytical Variance ◽  
Aflatoxin Concentration

The variability associated with the aflatoxin test procedure used to estimate aflatoxins in bulk shipments of dried figs was investigated. Sixteen 10 kg laboratory samples were taken from each of twenty commercial bulk lots of dried figs suspected of aflatoxin contamination. Two 55 g test portions were taken from each comminuted laboratory sample using water-slurry comminution methods. Finally, two aliquots from the test portion/solvent blend were analysed for both aflatoxin B1 and total aflatoxins. The total variance associated with testing dried figs for aflatoxins was measured and partitioned into sampling, sample preparation and analytical variance components (total variance is equal to the sum of the sampling variance, sample preparation variance, and analytical variance). Each variance component increased as aflatoxin concentration increased. Using regression analysis, mathematical expressions were developed to model the relationship between aflatoxin concentration and the total, sampling, sample preparation and analytical variances when testing dried figs for aflatoxins. The regression equations were modified to estimate the variances for any sample size, test portion size, and number of analyses for a specific lot aflatoxin concentration. When using the above aflatoxin test procedure to sample a fig lot at 10 μg/kg total aflatoxins, the sampling, sample preparation, analytical, and total variances were 47.20, 0.29, 0.13, and 47.62, respectively. The sampling, sample preparation, and analytical steps accounted for 99.1, 0.6, and 0.3% of the total variance, respectively. For the aflatoxin test procedure used in this study, the sampling step is the largest source of variability.

Estimating sampling variance and local environmental heterogeneity for both known and estimated analytical variance

Chemosphere ◽  
1996 ◽  
Vol 32 (6) ◽  
pp. 1133-1151 ◽  
Author(s):  
Malcolm J.R. Clark ◽  
Mark C.A. Laidlaw ◽  
Susan C. Ryneveld ◽  
Miranda I. Ward
Keyword(s):  
Environmental Heterogeneity ◽  
Sampling Variance ◽  
Analytical Variance

Analytical variation in metabolic profile testing

1973 ◽  
Vol 40 (1) ◽  
pp. 85-92 ◽  
Author(s):  
R. Manston ◽  
G. J. Rowlands
Keyword(s):  
Quality Control ◽  
Metabolic Profile ◽  
Dairy Herds ◽  
Population Variance ◽  
Analytical Variance ◽  
Average Population ◽  
Analytical Procedures ◽  
Analytical Variation

SummaryResults are presented demonstrating quality control of the analytical procedures used during the application of metabolic profile tests to dairy herds over a period of 3 years. The significance of analytical variance is discussed in relation to the average population variance in dairy herds.It is concluded that analytical variance can be restricted to reasonable proportions providing that careful quality control is continuously employed.

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