Method, Validity, and Variability in the Age Determination of Yellowtail Rockfish (Sebastes flavidus), Using Otoliths

1979 ◽  
Vol 36 (4) ◽  
pp. 377-383 ◽  
Author(s):  
Daniel K. Kimura ◽  
Ruth R. Mandapat ◽  
Sandra L. Oxford
Keyword(s):  
Standard Deviation ◽  
Coefficient Of Variation ◽  
Variance Components ◽  
Variance Component ◽  
Age Determination ◽  
Annular Zone ◽  
Total Variability ◽  
Males And Females ◽  
Age Category

A method using otoliths is presented for the age determination of yellowtail rockfish (Sebastes flavidus). Most of the details of this method are applicable to other species of rockfish. The method is validated in younger fish by documenting growth of the otolith annular zone by month, and by comparison with ages read from scales. Further validation is provided by length-at-age data, which show monotone growth for both males and females. Age reader variability was analyzed for each age category using random effects analysis of variance. This analysis showed that within-reader variances were similar for the two readers. Although there were significant variance components due to between-reader differences for aging some age categories, the contribution of this variance component to total variability was negligible. The standard deviation for an age determination of an otolith was similar for both readers, ranging from about 0.6 at 8 yr to about 1.6 at 19 yr. For both readers, the coefficient of variation was approximately 0.08 at all ages. Key words: Sebastes flavidus, age determination, otoliths

Use of Stabilized Plasma Arc Excitation in Determining the Element Boron in Gasoline

1965 ◽  
Vol 19 (2) ◽  
pp. 57-58 ◽  
Author(s):  
M. S. Vigler ◽  
J. K. Failoni
Keyword(s):  
Standard Deviation ◽  
Sample Preparation ◽  
Ethyl Alcohol ◽  
Coefficient Of Variation ◽  
Internal Standard ◽  
National Bureau ◽  
Plasma Arc ◽  
Buffer Solution ◽  
Arc Excitation

This report describes the use of a stabilized plasma arc source in the quantitative spectrographs determination of boron in gasoline. The advantage is that the plasma arc requires no preliminary sample preparation other than addition of nickel hexoate internal standard in ethyl alcohol buffer solution. The National Bureau of Standards # 1063 menthyl borate may be used for preparing calibration curves. The method is applicable to the determination of boron in the range of 0.0001 to 0.0010 per cent. The standard deviation is 0.000055 per cent; the coefficient of variation is 8.1 per cent.

Determination of Soy Products in Meat-Soy Blends

1974 ◽  
Vol 57 (4) ◽  
pp. 841-846
Author(s):  
Marvin W Formo ◽  
Guy R Honold ◽  
David B Maclean
Keyword(s):  
Standard Deviation ◽  
Atomic Absorption ◽  
Computer Analysis ◽  
Coefficient Of Variation ◽  
Ground Beef ◽  
Atomic Absorption Spectrophotometry ◽  
Average Concentration ◽  
Soy Flour ◽  
Absorption Spectrophotometry

Abstract The concentrations of various elements and fiber in ground beef and textured soy flour were measured, respectively, by atomic absorption spectrophotometry and a modified AOAC fiber method. The average concentration, standard deviation, and coefficient of variation for magnesium, manganese, and fiber, respectively, in textured soy flour are 2948 mg/kg, 186 mg/kg, 6.3% ; 33.4 mg/kg, 3.4 mg/kg, 10.1% ; 2.03%, 0.27%, 13.3%. The average concentration, standard deviation, and coefficient of variation for magnesium, manganese, and fiber, respectively, in regular ground beef are 151 mg/kg, 7.4 mg/kg, 4.9% ; 0.125 mg/kg, 0.025 mg/kg, 20%; 0.01%. From computer analysis of the data from an interlaboratory study of the analysis of textured soy flour–ground beef mixtures, the expected total errors (one standard deviation in absolute percentages) of the method applied to a product containing 20% textured soy flour hvdrated 1+2 were as follows for the respective indices used: magnesium 1.8%, manganese 2.7%, and fiber 8.8%. Analysis of ground beef and textured soy flour for ash, hemicellulose, stachyose, phosphorus, potassium, copper, and zinc revealed that these constituents were not suitable indices of textured soy flour content in textured soy flour-ground beef mixtures.

scholarly journals An Inter-Laboratory Comparison for the Urinary Acrolein Biomarker 3-Hydroxypropyl-Mercapturic Acid (3-HPMA)

2017 ◽  
Vol 27 (5) ◽  
pp. 65-76
Author(s):  
Gerhard Scherer ◽  
Wolf-Dieter Heller ◽  
Michael McEwan ◽  
Thomas Göen ◽  
Peter Joza ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Coefficient Of Variation ◽  
Solid Phase ◽  
Mercapturic Acid ◽  
Heavy Smoking ◽  
Peak Areas ◽  
Good Repeatability ◽  
Work Up ◽  
Globally Distributed

Summary An inter-laboratory comparison study on the acrolein biomarker of exposure 3-hydroxypropyl-mercapturic acid (3-HPMA) with 12 laboratories from 7 globally distributed countries was performed. The laboratories received coded triplicates of 4 spiked and lyophilized urine samples (LU, 12 samples) as well as 5 authentic urine pool samples (PU, 15 samples) covering the 3-HPMA concentration range from background (non-smoking) to heavy smoking levels for analysis by using their own (in-house) analytical method. All laboratories applied liquid chromatography with tandem mass spectrometry (LC-MS/MS), with most of them (10 of 12) using solid phase extraction (SPE) as sample work-up procedure. The intra-laboratory variation (indicating repeatability) was determined by calculating the standard deviation (sr) and the coefficient of variation (CVr) of the triplicates, whereas the inter-laboratory variation (indicating reproducibility) was determined by calculating the standard deviation between laboratories (sR) and the corresponding coefficient of variation (CVR). After removal of outlier samples or laboratories, the mean CVr values for LU and PU test samples ranged from 2.1–3.6% (mean: 2.8%) and 2.4–3.7% (mean: 3.3%), respectively, indicating good repeatability for the determination of 3-HPMA in both sample types. CVR for LU and PU test samples ranged from 9.1–31.9% (mean: 18.8%) and 13.9–27.0% (mean: 18.5%), respectively, indicating limited reproducibility in 3-HPMA analysis for both sample types. Re-calculation of the PU results by applying an embedded calibration (EC), derived from the reported peak areas for the LU test samples, somewhat improved the CVR values (range: 9.6–28.8%, mean: 16.7%). It is concluded that the intra-laboratory variation (repeatability) in the determination of 3-HPMA in urine is in general acceptable in the participating laboratories, while the inter-laboratory variability requires further improvement. The relatively small reduction in the inter-laboratory variability (sR and CVR) by applying an EC suggests that other methodological factors than the standard reference material for 3-HPMA have to be addressed to achieve further improvement in reproducibility.

scholarly journals Secondary Dentin as an Aid in Gender Predilection: A Forensic Study

2021 ◽  
Author(s):  
Himanshu Singh ◽  
Vedant Patel ◽  
Rahul A. Razdan ◽  
Deepak Jha ◽  
Prachi Nayak ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Forensic Odontology ◽  
Analysis Software ◽  
Image Analysis Software ◽  
Males And Females ◽  
The Mean ◽  
Secondary Dentine ◽  
Dentin Thickness

Abstract Background Forensic odontology deals with age, sex, and race determination of the deceased at crime scenes, disasters, or natural calamities. Studies regarding the role of secondary dentin in age estimation have been documented on a several occasions in the literature but use of secondary dentin in gender predilection has not yet been documented. So, the present study was aimed at using the secondary dentin as a diagnostic tool in gender predilection. Materials and Methods The study included a total of 20 samples (10 males and 10 females). Extracted teeth were collected and placed in 10% neutral buffered formalin solution. The sections were ground on Arkansas stone until the appropriate thickness of the ground sections was achieved. The freshly prepared ground section was mounted on a slide using DPX mounting media. Ground sections were visualized under a microscope and the thickness of secondary dentine was measured using the image analysis software. Results The data were collected and subjected to group statistics. The secondary dentin thickness of all the samples, males and females, was measured. It was observed in our study that the mean thickness of secondary dentin was more in male samples (0.2970) with the standard deviation of 0.01494, as compared with that of females where the mean thickness was found to be 0.1970 with the standard deviation of 0.02058. Conclusion This study has shown that variation in secondary dentin thickness does exist between male and female groups. This criterion can be considered as an aid for gender determination in the future.

The study of variability in some wool traits in a coarse wool breed of sheep

1973 ◽  
Vol 80 (2) ◽  
pp. 233-238 ◽  
Author(s):  
R. A. Guirgis
Keyword(s):  
Statistical Analysis ◽  
Standard Deviation ◽  
Major Part ◽  
Fibre Diameter ◽  
Coefficient Of Determination ◽  
Main Contributor ◽  
Total Variability ◽  
The Mean ◽  
Staple Length

SummaryWool samples from 47 Barki yearlings were taken from five positions during two years to study the variability in the fleece, the cause of variability and associations between different fleece traits. Statistical analysis has indicated the following significant points.An antero-posterior gradient occurred in the different traits under study. When medullation was discarded, though it was of a low magnitude (3·9%), a reduction of 5·89% in the mean fibre diameter and of 18·33% in its standard deviation occurred.The position most representative of the whole fleece varied with the trait. It is recommended to take three sampling positions forming a triangle, withers, mid-side and hip, to represent the Barki fleece.The animals contributed the major part in the variability of mean fibre diameter (1), the standard deviation of fibre diameter (S.D.1), percentage medullation, mean fibre diameter after discarding the medullated fibres (2), the standard deviation of fibre diameter after discarding the medullated fibres (S.D.2), the contribution of medullation to the total variability, percentage fine fibres and percentage coarse fibres. The positions were the main contributor to the variability of percentage kemp fibres, staple length, medullation index and to a certain extent to that of the kemp score. The year played a significant part in the variability except for 2 and S.D.2.The highest correlations with the standard deviation of fibre diameter were those of percentage medullation and kemp score. These three variables when considered separately accounted for 0·47, 0·35 and 0·31 respectively of the variability in S.D.Equations were obtained to predict the standard deviation from both the mean fibre diameter and the percentage medullation and to predict the mean fibre diameter from the staple length and the kemp score. The coefficient of determination of the first set of equations ranged from 0·47 to 0·56 while that of the second set ranged between 0·07 and 0·51 for different positions.

scholarly journals Sex Determination Using Inion-Opistocranium-Asterion (IOA) Triangle in Nigerians’ Skulls

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
C. N. Orish ◽  
B. C. Didia ◽  
H. B. Fawehinmi
Keyword(s):  
Sexual Dimorphism ◽  
Linear Regression ◽  
Coefficient Of Variation ◽  
Individual Identification ◽  
Male And Female ◽  
Gender Determination ◽  
Important Concern ◽  
Males And Females ◽  
The Right

Background. Determination of sex is an important concern to the forensic anthropologists as it is critical for individual identification. This study has investigated the existence of sexual dimorphism in the dimensions and the area of the IOA triangle. Methods. A total of 100 adult dry skulls, (78 males; 22 females) from departments of anatomy in Nigerian universities were used for this study. Automatic digital calliper was used for the measurement. Coefficient of variation, correlation, linear regression, percentiles, and sexual dimorphism ratio were computed from the IOA triangle measurements. The IOA triangle area was compared between sexes. Results. The male parameters were significantly (P<0.05) higher than female parameters. The left opistocranium-asterion length was 71.09±0.56 and 61.68±3.35 mm and the right opistocranium-asterion length was 69.73±0.49 and 60.92±2.10 mm for male and female, respectively. A total area of IOA triangle of 1938.88 mm2 and 1305.68 mm2 for male and female, respectively, was calculated. The left IOA indices were 46.42% and 37.40% in males and females, respectively, while the right IOA indices for males and females were 47.19% and 38.87%, respectively. Conclusion. The anthropometry of inion-opistocranium-asterion IOA triangle can be a guide in gender determination of unknown individuals.

Mass Loss on Drying for Instant Coffee: Collaborative Study

1980 ◽  
Vol 63 (2) ◽  
pp. 178-179
Author(s):  
William P Clinton ◽  
Paul H Manni ◽  
John M Ferry
Keyword(s):  
Standard Deviation ◽  
Mass Loss ◽  
Coefficient Of Variation ◽  
Collaborative Study ◽  
Instant Coffee ◽  
Reproducibility Standard Deviation ◽  
Repeatability Standard Deviation ◽  
Working Method

Abstract A collaborative study was undertaken to define an acceptable routine working method for determination of mass loss in instant coffee. Fourteen laboratories of 24 invited to participate submitted results. The repeatability standard deviation and coefficient of variation were 0.026 and 0.7%, respectively. The reproducibility standard deviation and coefficient of variation were 0.153 and 3.8%, respectively. The method has been adopted as official first action.

Collaborative Study on the Analysis of Amyl p-Dimethylaminobenzoate in Suntan Preparations by Chromatography and Ultraviolet Spectrophotometry

1970 ◽  
Vol 53 (1) ◽  
pp. 84-86
Author(s):  
Henry M. Davis
Keyword(s):  
Standard Deviation ◽  
Coefficient Of Variation ◽  
Collaborative Study ◽  
Uv Spectrophotometry ◽  
Partition Chromatography ◽  
Ultraviolet Spectrophotometry

Abstract A method for the determination of amyl p-dimethylaminobenzoate in suntan preparations was submitted for collaborative study. The sunscreen is isolated by partition chromatography and determined by UV spectrophotometry. The data of two collaborators were discarded. Results for the six collaborators show recoveries of 94-101% for samples containing from 10.2 to 23.1 mg sunscreen. The standard deviation varied from 0.18 to 0.72 and the coefficient of variation from 1.84 to 3.6%. It is recommended that the method be adopted as official first action.

Liquid Chromatographic Determination of Chlortetracycline Hydrochloride in Ruminant and Poultry/Swine Feeds

1991 ◽  
Vol 74 (5) ◽  
pp. 780-784 ◽  
Author(s):  
David C Holland ◽  
Kent C Faul ◽  
Jose E Roybal ◽  
Robert K Munns ◽  
Wilbert Shimoda
Keyword(s):  
Standard Deviation ◽  
Coefficient Of Variation ◽  
Methylene Chloride ◽  
Chromatographic Determination ◽  
Average Recovery ◽  
Liquid Chromatographic Determination ◽  
Feed Premix ◽  
Liquid Chromatographic

Abstract A liquid chromatographic (LC) method is described for the determination of chlortetracycline hydrochloride (CTC) in poultry/swine and ruminant feeds in the 10-100 ppm range and in premix. CTC is extracted from ground feed/premix with acidified acetone, and the extract is filtered through a Millex-HV filter or disposable C 18 column. The filtrate Is partitioned with methylene chloride when additional cleanup is necessary. A Nova-Pak C 18 column Is used for LC separation with determination at 370 nm. The average recovery of CTC from premix was 95% with a standard deviation (SD) of 1.70 and a coefficient of variation (CV) of 1.79%. The overall average recovery from feeds was 77% with an SO of 3.18 and a CV of 4.10%.

scholarly journals A Method for the Determination of Nicotine in Lung Tissue of Hamsters / Eine Methode zur Bestimmung des Nikotins in Hamsterlungen

1966 ◽  
Vol 3 (6) ◽  
Author(s):  
H. Elmenhorst
Keyword(s):  
Standard Deviation ◽  
Hydrochloric Acid ◽  
Lung Tissue ◽  
Coefficient Of Variation ◽  
Steam Distillation ◽  
Analytical Procedure ◽  
Limit Of Detection ◽  
Experimental Animals ◽  
Inferior Limit

AbstractA method for the determination of nicotine in lung tissue is presented. The nicotine is extracted from homogenized lung tissue by means of a mixture of hydrochloric acid and methanol. It is then spectrophotometrically determined after the disturbing accompanying substances have been eliminated by a preliminary acid steam distillation. The method's inferior limit of detection is 40 µg of nicotine contained in 3 lungs, which corresponds to 17.7 µg of nicotine per gramme of lung tissue. In the case of nicotine contents of 50 µg per analytical procedure the standard deviation of the method was found to be 1.7 µg, and the resulting coefficient of variation was calculated to be 3.4 %. The procedure is simple and therefore suitable for the study of numerous samples. The exposure of hamsters to inhaled raw cigarette smoke revealed that the nicotine content of lungs of experimental animals augments with the number of burnt cigarettes and the duration of inhalation. The reproducibility of Dontenwill's inhalation procedure was tested and proved to be satisfactory. The coefficient of variation within two series of inhalation experiments was found to be between 4.1 and 5.2 %

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