Determination of the Weibull parameters from the mean value and the coefficient of variation of the measured strength for brittle ceramics

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.

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Determination of Plasminogen in Clots and Thrombi

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655625 ◽

1966 ◽

Vol 16 (01/02) ◽

pp. 038-050 ◽

Cited By ~ 6

Author(s):

Ulla Hedner ◽

Inga Marie Nilsson ◽

B Robertson

Keyword(s):

Mean Value ◽

Main Mechanism ◽

Clot Lysis ◽

Post Mortem ◽

Digestion Time ◽

Normal Volunteers ◽

Casein Solution ◽

The Mean

SummaryThe plasminogen content was determined by a casein method in plasma and serum from 20 normal volunteers. The mean plasminogen content was found to be 10.1 ACU (the arbitrary caseinolytic unit defined in such a way that using a 3% casein solution and a digestion time of 20 min. at 37°C, 10 ACU gave an extinction of 0.300). No difference between serum and plasma regarding the plasminogen content was found.Plasminogen was determined in drained and drained plus washed clots prepared from 2 ml plasma. The highest values found in the drained clots were 0.9 ACU/clot and 0.2 ACU/clot in the drained plus washed clots.Plasminogen was also determined in drained and drained plus washed clots prepared from plasma with added purified plasminogen. The plasminogen was recovered in the washing fluid. According to these tests, then, purified added plasminogen is washed out of the clots.The plasminogen content of 20 thrombi obtained post mortem was also determined. The mean value was found to be 0.7 ACU/cm thrombus. Judging from our results, the “intrinsic clot lysis theory” is not the main mechanism of clot dissolution.

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Determination of the Probability Distribution of the Mean Sound Level

Archives of Acoustics ◽

10.2478/v10168-010-0041-1 ◽

2010 ◽

Vol 35 (4) ◽

pp. 543-550 ◽

Cited By ~ 4

Author(s):

Wojciech Batko ◽

Bartosz Przysucha

Keyword(s):

Probability Distribution ◽

Probability Distribution Function ◽

Mean Value ◽

Sound Level ◽

Function Form ◽

Noise Levels ◽

Logarithmic Mean ◽

The Mean ◽

Estimation Of Uncertainty

AbstractAssessment of several noise indicators are determined by the logarithmic mean <img src="/fulltext-image.asp?format=htmlnonpaginated&src=P42524002G141TV8_html\05_paper.gif" alt=""/>, from the sum of independent random resultsL1;L2; : : : ;Lnof the sound level, being under testing. The estimation of uncertainty of such averaging requires knowledge of probability distribution of the function form of their calculations. The developed solution, leading to the recurrent determination of the probability distribution function for the estimation of the mean value of noise levels and its variance, is shown in this paper.

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ENZYMATISCH-FLUOROMETRISCHE BESTIMMUNG DER CORTISOLBINDUNGSKAPAZITÄT DES PLASMA

Acta Endocrinologica ◽

10.1530/acta.0.0560099 ◽

1967 ◽

Vol 56 (1) ◽

pp. 99-106 ◽

Cited By ~ 7

Author(s):

K. Leybold ◽

J. Rieper ◽

L. Weissbecker

Keyword(s):

Binding Capacity ◽

Liver Microsomes ◽

Mean Value ◽

Female Rats ◽

Plasma Samples ◽

Simple Method ◽

Adult Men ◽

The Mean ◽

Precision And Accuracy

ABSTRACT A simple method for the determination of cortisol-binding capacity is described. For saturation of the cortisol-binding proteins, plasma samples are incubated with an excess of cortisol. In the next step NADPH and liver microsomes of female rats are added. The microsomal Δ4-3-ketosteroid hydrogenase only reduces non protein-bound cortisol to tetrahydrocortisol-5α. Then the steroids are extracted by dichloromethane, and after some purification steps analyzed by fluorometry. Tetrahydrocortisol gives practically no fluorescence. The cortisol determined by this method corresponds to protein-bound cortisol and indicates the extent of cortisolbinding capacity. Precision and accuracy of the method were found to be good. The values of cortisol-binding capacity obtained by our method are compared with the results of other authors. The mean value of adult men was 25.5 ± 3.4 μg/100 ml, that of pregnant women, mens IX-X, 42.3 ± 4.2 μg/100 ml.

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Transrenal passage of nitrates and nitrites in calves (short communication)

Archives Animal Breeding ◽

10.5194/aab-42-235-1999 ◽

1999 ◽

Vol 42 (3) ◽

pp. 235-240

Author(s):

A. Jacková ◽

P. Siklenka ◽

J. Pleva

Keyword(s):

Short Communication ◽

Clinical Signs ◽

Potassium Nitrate ◽

Mean Value ◽

Significant Elevation ◽

Total Hemoglobin ◽

The Mean ◽

Nitrate And Nitrite ◽

Nitrite Content

Abstract. In a study with 12 calves on milk nutrition, the course of methemoglobinemia as well as ttansrenal passage of nitrates and nitrites after single per os administrations of 4 g NaNO2 per animal and 30 g KNO3 per animal in the form of water Solutions has been observed. The response of the organism of calves to per os administered doses of sodium nitrite and potassium nitrate was observed by the determination of tlie methemoglobin percentage in blood and the nitrate and nitrite content in urine before the administration ofthe respective dose and after h 1, 2, 3 and 4 after the administration. A significant elevation in the values of methemoglobin was recorded after h 2 after the administration of 4g NaNO3 per animal. The mean value of methemoglobin in blood was 18.84% of total hemoglobin. A slight decline in the values occurred as early as after h 3 after the administration. Of clinical signs, cyanosis of visible mucosae was observed. The highest nitrite and nitrate values in urine were determined after h 2 after per os administration of 4g NaNO2, With the administration of 30g KNO3 per animal, the most pronounced elevation in methemoglobinemia was observed after h 3, when the means values of methemoglobin was 11,75%. Of clinical signs, only slight cyanosis of mucosae was detectable. Maximum values of nitrates in urine of experimental calves after h 3 after the administration of 30 g KNO3 per animal, with the mean value of 29,9 mM NO3−1 clearly demonstrate a good transrenal passage of nitrates in calves on milk nutrition.

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Branching exponent heterogeneity and wall shear stress distribution in vascular trees

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.2001.280.3.h1256 ◽

2001 ◽

Vol 280 (3) ◽

pp. H1256-H1263 ◽

Cited By ~ 23

Author(s):

Kelly L. Karau ◽

Gary S. Krenz ◽

Christopher A. Dawson

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Coefficient Of Variation ◽

Vessel Diameter ◽

Mean Value ◽

Heterogeneous Distribution ◽

Uniform Shear ◽

The Mean ◽

Wall Shear ◽

Stress Dependent

A bifurcating arterial system with Poiseuille flow can function at minimum cost and with uniform wall shear stress if the branching exponent ( z) = 3 [where z is defined by ( D 1) z = ( D 2) z + ( D 3) z ; D 1 is the parent vessel diameter and D 2 and D 3 are the two daughter vessel diameters at a bifurcation]. Because wall shear stress is a physiologically transducible force, shear stress-dependent control over vessel diameter would appear to provide a means for preserving this optimal structure through maintenance of uniform shear stress. A mean z of 3 has been considered confirmation of such a control mechanism. The objective of the present study was to evaluate the consequences of a heterogeneous distribution of z values about the mean with regard to this uniform shear stress hypothesis. Simulations were carried out on model structures otherwise conforming to the criteria consistent with uniform shear stress when z = 3 but with varying distributions of z. The result was that when there was significant heterogeneity in z approaching that found in a real arterial tree, the coefficient of variation in shear stress was comparable to the coefficient of variation in z and nearly independent of the mean value of z. A systematic increase in mean shear stress with decreasing vessel diameter was one component of the variation in shear stress even when the mean z = 3. The conclusion is that the influence of shear stress in determining vessel diameters is not, per se, manifested in a mean value of z. In a vascular tree having a heterogeneous distribution in zvalues, a particular mean value of z (e.g., z = 3) apparently has little bearing on the uniform shear stress hypothesis.

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Determination of high-density lipoprotein phospholipids in serum.

Clinical Chemistry ◽

10.1093/clinchem/26.9.1275 ◽

1980 ◽

Vol 26 (9) ◽

pp. 1275-1277 ◽

Cited By ~ 11

Author(s):

Y Yamaguchi

Keyword(s):

High Density Lipoprotein ◽

Density Lipoprotein ◽

Mean Value ◽

High Density ◽

High Density Lipoproteins ◽

Low Density ◽

Very Low Density Lipoproteins ◽

Color Development ◽

The Mean

Abstract I describe a method for measuring high-density lipoprotein phospholipids. Magnesium chloride and dextran sulfate are used to precipitate all low-density and very-low-density lipoproteins. The supernate contains only high-density lipoproteins, the phospholipid concentration of which is determined by an enzymic method. The precision of the method (CV) is 2.35% (10 repeated assays), and the mean value for HDL-phospholipids was 1006 (SD 248) mg/L for 30 apparently healthy subjects. I used electrophoresis and enzymic color development to confirm the presence of HDL-phospholipids. Results are compared with those obtained by an ultracentrifugation method.

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Determination of oxygenated, mixed venous blood CO2 tension by a breath-holding method

Journal of Applied Physiology ◽

10.1152/jappl.1960.15.2.225 ◽

1960 ◽

Vol 15 (2) ◽

pp. 225-228 ◽

Cited By ~ 10

Author(s):

John H. Knowles ◽

William Newman ◽

Wallace O. Fenn

Keyword(s):

Venous Blood ◽

Mean Value ◽

Rate Of Change ◽

Breath Holding ◽

Mixed Venous Blood ◽

Clinical Method ◽

Straight Line ◽

Zero Rate ◽

The Mean

At the end of a normal expiration the subject inhaled a given volume of gas mixtures containing different concentrations of CO2 in O2 from 5 to 17%. These were held in the lung for 3 and then again for 12 seconds and were then expired and analyzed. Analyses were made with an infrared analyzer and times were obtained from the graphical record. If the rate of change of CO2 tension is plotted against the mean CO2 tension a straight line results which passes through zero rate at the tension which equals the tension of CO2 in the mixed oxygenated venous blood. From the slope of this straight line it is possible to calculate the cardiac output if the lung volume and slope of the CO2 dissociation curve of the blood are known. Data are presented from 37 experiments on 10 subjects. The method is believed to be theoretically sound but has not been validated as a practical clinical method. Occasional erratic points were obtained, especially in untrained subjects. The standard error of the mean value for venous CO2 tension was 1.9 mm Hg. Submitted on July 13, 1959

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Optimization of Sweep Codistillation Apparatus for Determination of Coumaphos and Other Organophosphorus Pesticide Residues in Animal Fat

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/70.3.442 ◽

1987 ◽

Vol 70 (3) ◽

pp. 442-445

Author(s):

Robert L Brown ◽

Clinton N Farmer ◽

Roderick G Millar

Keyword(s):

Coefficient Of Variation ◽

Pesticide Residues ◽

Organophosphorus Pesticides ◽

Organophosphorus Pesticide ◽

Optimum Conditions ◽

Animal Fat ◽

Sweep Time ◽

Coefficients Of Variation ◽

The Mean

Abstract Optimum conditions have been developed for the quantitative recovery of coumaphos from animal fat by using a commercial sweep codistillation unit. Under the conditions specified (255°C distillation temperature, 250 mL/min of nitrogen, 60 min sweep time) and using Florisil trapping, the mean recovery of coumaphos was 91% with a coefficient of variation of 6%. Other organophosphorus pesticides recovered include diazinon, chlorpyrifos, ethion, and bromophos-ethyl with recoveries ranging from 90 to 96% and coefficients of variation ranging between 4 and 6%.

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Determination of Zearalenone in Corn: Collaborative Study

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/59.3.666 ◽

1976 ◽

Vol 59 (3) ◽

pp. 666-670

Author(s):

Odette L Shotwell ◽

Marion L Goulden ◽

Glenn A Bennett

Keyword(s):

Statistical Analysis ◽

Thin Layer ◽

Coefficient Of Variation ◽

Collaborative Study ◽

Corn Sample ◽

Yellow Corn ◽

Coefficients Of Variation ◽

The Mean

Abstract Corn samples spiked at levels of 100, 300, 1000, and 2000 μg zearalenone/kg were sent to 22 collaborators for analysis by the Eppley method. All samples were yellow corn except one white corn sample spiked at 2000 μg/kg. Results from 16 collaborators were statistically analyzed. Only 4 of 16 collaborators detected zearalenone in the sample containing 100 μg/kg, but 11 detected the toxin in the sample containing 300 μg/kg. Average recoveries from all samples were 129% at 300 μg/kg, 101% at 1000 μg/kg, and 88% at 2000 μg/kg. The between-laboratory coefficients of variation were 53.0% at 300 μg/kg, 38.2% at 1000 μg/kg, and 27.0% at 2000 μg/kg. Five naturally contaminated corn samples, one in triplicate, were also provided. The mean level of zearalenone in the naturally contaminated samples ranged from 431 to 7622 μg/kg. The mean coefficient of variation for all samples was 40.5%. Two collaborators measured quantities of zearalenone on thin layer chromatographic plates densitometrically. Their results were not included in the statistical analysis, but the results indicated that densitometric measurement, given proper dilutions of solutions, could be used. The method has been adopted as official first action.

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