bluuebunny/crossref_metadata_2025 huggingface dataset:
‘Shark in the Fish Tank’: Secrets and Stigma in Relational Desistance from Crime
Authors: Gålnander Robin
Published: February 2020

Processes of desistance from crime are intricate and, aside from concrete non-offending, they involve a change in self-perception and an acceptance and recognition of reform by others. A criminalized lifestyle often comes with significant stigma, which together with segregation or exclusion from conventional society can render the procurement of such acceptance and recognition difficult. This article is based on findings from repeated in-depth interviews with desisting women who are just setting out to approach mainstream society. Focusing on the women’s experiences of managing concealable stigma when (re)turning to conventional society, the analysis advances the understanding of individual reform with a focus on relational aspects of desistance from crime.
Developing a measure of information seeking about phishing
Authors: Williams Emma J , Joinson Adam N
Published: February 2020

Phishing e-mails are fraudulent e-mails used to gain access to sensitive information or secure computer systems. They persuade users to click on malicious links, download attachments or provide sensitive information, such as usernames or passwords. One approach that aims to reduce people’s susceptibility to phishing is the provision of information to users regarding the phishing threat and the techniques used within phishing e-mails. In line with this, awareness campaigns are often used within organizations and wider society to raise awareness of phishing and encourage people to engage with protective information. However, the potential effectiveness of such approaches in reducing susceptibility remains uncertain. In particular, there is a lack of research investigating (i) whether the propensity to access such information may in itself influence susceptibility to phishing and (ii) the different factors that motivate people to engage with information in the first place. In order to understand how current and future interventions regarding phishing may be consumed by users, as well as their potential impact on phishing susceptibility, it is important to conduct theoretically based research that provides a foundation to investigate these issues. This study provides a first step in addressing this by developing and validating a theoretically based survey measure across two studies centred upon the constructs of protection motivation theory (perceived vulnerability, severity, self-efficacy and response efficacy) to assess the factors that influence whether people choose to keep up to date with protective information about phishing. This survey measure is then used within Study 2 to provide an initial investigation of the role of these constructs in (i) self-reported user intentions to keep up to date with phishing techniques in the future and (ii) phishing discrimination ability, assessed using a phishing quiz. Overall, higher perceived threat severity, self-efficacy and response efficacy were associated with greater intentions, while greater perceived vulnerability was associated with lower intentions. No relationship was found with phishing discrimination ability. By understanding the factors that influence user intention to maintain knowledge and seek information about phishing threats, it will be possible to ensure that, as effective interventions are developed, their potential impact can be maximized.
Host Tree Species Affects Spruce Budworm Winter Survival
Authors: Berthiaume Richard , Hébert Christian , Charest Martin , Dupont Alain , Bauce Éric
Published: February 2020

With current trends in global warming, it has been suggested that spruce budworm outbreaks may spread to northern parts of the boreal forest. However, the major constraints for a northward expansion are the availability of suitable host trees and the insect winter survival capacity. This study aimed to determine the effect of larval feeding on balsam fir, white spruce and black spruce on various spruce budworm life history traits of both the parental and the progeny generations. Results indicated that the weight of the overwintering larval progeny and their winter survival were influenced by host tree species on which larvae of the parental generation fed. White spruce was the most suitable host for the spruce budworm, producing the heaviest pupae and the heaviest overwintering larvae while black spruce was the least suitable, producing the smallest pupae and the smallest overwintering progeny. Overwintering larvae produced by parents that fed on black spruce also suffered higher winter mortality than individuals coming from parents that fed on balsam fir or white spruce. With current trends in global warming, spruce budworm is expected to expand its range to northern boreal forests where black spruce is the dominant tree species. Such northern range expansion might not result in outbreaks if low offspring winter survival on black spruce persist.
Bishop Bateman and Bury St Edmunds: The Two Laws Clash
Authors: McDonald Peter
Published: February 2020

Bishop Bateman’s assertion of his authority over the exempt abbey of Bury St Edmunds in 1345 brought him into conflict with a house closely linked to both papacy and Crown, and came at a time of Anglo-papal tensions. Bateman was no anti-papalist but, as a legal rigorist, wanted to satisfy himself about Bury’s claims to exemption and restrain its monks’ extra-mural misbehaviour. He had some basis for this in canon law, but the ensuing lawsuit at the papal curia seemed to be going against him until swept aside by a writ of prohibition. The monastery looked to the Crown as its chief protector, and the English courts asserted royal rights aggressively. They found Bateman and his commissaries in contempt for breaching the prohibition and for asserting that only the pope could confer exemption; the abbey’s papal privileges were only confirmations of royal charters. They confiscated Bateman’s temporalities and imposed massive fines, and the pope was powerless to intervene. This amounted to a repudiation of 250 years of canon law, harking back to the eleventh-century Eigenkirche. But Edward III needed Bateman as a diplomat, and imposed a compromise under which both sides withdrew their suits and he pardoned the bishop. As Anglo-papal relations settled after 1350, the Crown let canon law stand and did not enforce the doctrines developed in this case. Edward was content with bringing his bishops to heel, and the two systems resumed their normal co-operation. Still, the courts had set a new precedent for royal control.
Neck cannulation for bypass in redo sternotomy in children and adults with congenital heart disease
Authors: Mustafa Muhammad R , Neijenhuis Ralph M L , Furci Barbara , Tsang Victor T
Published: February 2020

OBJECTIVES

Patients with complex congenital heart disease carry an increased risk of damage to retrosternal structures each time they undergo redo sternotomy. The aim of this study was to evaluate the safety and efficacy of neck cannulation for peripheral cardiopulmonary bypass to alleviate the risks in high-risk redo sternotomy patients.

METHODS

Children and adults with congenital heart disease undergoing high-risk redo sternotomy were included in this retrospective study. The primary outcome was the safety and efficacy of neck cannulation for cardiopulmonary bypass. The secondary outcome was to assess preoperative risk factors as an indication for neck cannulation. The right common carotid artery and right internal jugular vein were cannulated and full cardiopulmonary bypass was initiated with vacuum-assisted venous drainage. Redo sternotomy was performed on a decompressed heart, and bifrontal regional cerebral oxygen saturation was monitored via near-infrared spectroscopy.

RESULTS

In total, 35 patients were included. No mortality, neurological or vascular complications occurred postoperatively. Mean left- and right-sided near-infrared spectroscopy were 70.0% (±10.5) and 64.2% (±12.0), respectively, and the mean difference was 5.7% (±6.9). Main preoperative risk factors were; adherent ascending aorta (45.7%), adherent conduit (40%), severely dilated retrosternal right ventricle (17.1%) and skeletal deformations (14.3%).

CONCLUSIONS

Cannulation of the right neck vessels for peripheral cardiopulmonary bypass prior to high-risk redo sternotomy in children and adults with congenital heart disease is a safe and effective strategy. In combination with near-infrared spectroscopy monitoring, adequate cerebral oxygenation can be ensured while the risk of catastrophic haemorrhage is minimized.
Spectrophotometric Determination of Maleic Hydrazide in Tobaccos
Authors: Hoffman I
Published: February 2020

Maleic hydrazide (6-hydroxy-3-(2H) pyridazinone) has properties that make it an important regulator for the control of sucker growth in tobacco. The stability and persistence of maleic hydrazide in plants was reviewed by Smith and co-workers (3). Several procedures have been reported for its determination in plant material (1, 2, 4) but these have proved to be unsatisfactory when applied to tobacco. This failure is due primarily to the strong red interfering color which results when tobacco in sodium hydroxide solution is distilled with added zinc. The reported procedures attempt to minimize this interference by the use of empirical constants and absorbance ratio factors. This paper outlines a modified procedure of greatly increased sensitivity which removes the interference entirely, and which is applicable to various types of tobacco tested (flue-cured, cigar, burley, and aromatic)
One-Step Chromatographic Cleanup of Chlorinated Hydrocarbon Pesticide Residues in Butterfat. II. Chromatography on Florisil
Authors: Moats William A
Published: February 2020

The procedure for chromatography on Florisil was modified by using methylene chloride-petroleum ether mixtures to improve separation of insecticides from fat. Combined with paper chromatography, it provides a screening procedure for insecticide residues in dairy products that is comparable in speed and simplicity to total chloride methods but is of superior sensitivity.
Microcoulometric Gas Chromatographic Determination of Thiodan and Tedion in Green Vegetables
Authors: Burke Jerry , Mills Paul A
Published: February 2020

Thiodan and Tedion are extracted from vegetables by alcohol-hexane, cleaned up on a Florisil column, and determined by microcoulometric gas chromatography. Fractional elution from the Florisil column separates Thiodan from DDT, which has a conflicting GLC retention time. Dieldrin and endrin are eluted with Thiodan from Florisil; their GLC retention times conflict with that of Thiodan. However, if they are present, identification and semiquantitative estimation are possible.

Eluents from the Florisil column are not sufficiently “clean” for GLC when waxy-type vegetables (cole crops) are being analyzed, and additional treatment with the AOAC carbon mixture is utilized.
Rapid Method for Chlorinated Pesticide Residues in Nonfatty Foods
Authors: Mills Paul A , Onley J H , Gaither R A
Published: February 2020

Portions of several previously reported methods have been combined, condensed, and modified to provide a rapid, simple procedure for determining chlorinated organic pesticide residues in nonfatty foods. The method is believed to be applicable to 21 pesticides in a variety of foods. Results are reported for 5 pesticides in 11 foods.
Recovery of Sulphenone from Agriculturally Treated Crops
Authors: Shuman Harry
Published: February 2020

Hexane as a stripping solvent in the first action method for determination of Sulphenone makes possible the direct application of the relatively simple acetonitrile cleanup to an aliquot of strip solution prior to isolation of p-chlorophenyl phenyl sulfone by Magnesol chromatography. Benzene stripping (as in method 24.106(a) for DDT) is superior to the current hexane stripping procedure, 24.146, for Sulphenone residues on apples, but shows no advantage over the hexane procedure for peaches. Pears have not been included in the study but it is reasonable to assume that firm pears (able to withstand tumbling at 75-100 rpm) would be classified with apples. It is proposed that two stripping procedures be included in the method for Sulphenone, based on differences in epidermal characteristics and firmness of the fruit. The stripping efficiency of these procedures should be 95% for apples and firm pears, 90% for peaches, and 80-90% for soft pears.
Programmed Temperature Gas Chromatography (PTGC) and Microcoulometric Detection of Chlorinated Insecticides
Authors: Burke Jerry
Published: February 2020

Commercial models of a programmed temperature gas chromatograph and microcoulometric detection system were combined to study programmed temperature gas chromatography (PTGC) of chlorinated insecticides. PTGC permitted the analysis of samples containing materials whose volatilities cover a wide range. PTGC produced better chromatograms and was faster than isothermal gas chromatography. PTGC did not achieve separations which were not possible by isothermal gas chromatography. Operating parameters for a PTGC residue screening operation were determined. Relative retention times at these conditions are given for 22 pesticides. Other advantages of the PTGC instrumentation are noted.
Procedure for Distinguishing Compound OW-9 Residues from Aramite Residues on Citrus Fruits
Authors: Blinn R C , Gunther F A
Published: February 2020

The acaricide OW-9 is a mixture of two organosulfites closely related in structure to Aramite. Because OW-9 responds to the previously Aramiteselective “ethylene oxide method,” a procedure was designed to distinguish OW-9 residues from those resulting from illegal uses of Aramite. Vapor phase and thin-layer chromatographic techniques have satisfactorily separated Aramite from the OW-9 compounds so that they can be identified by several means.
Comparison of Laboratory Techniques for the Determination of Pesticide Residues in Milk
Authors: Henderson J Lloyd
Published: February 2020

Of the techniques available for specific pesticide residues, fly bioassay is non-specific and not very sensitive; total organic chloride determination also lacks specificity; the AOAC colorimetric method produces variable results, lacks sensitivity for low levels of residues, and does not cover the range of residues likely to be present in milk. Chromatographic tests are most satisfactory. Microcoulometric gas chromatography has many advantages but requires a skilled analyst. Electron-capture gas chromatography is promising but has not been fully developed. The Mills test, which combines column cleanup with identification by paper chromatography, is a rapid, practical screening test. In a collaborative comparison of the chromatographic procedures, microcoulometry tended to give higher results than the Mills test; electron-capture gave lower results than the other two methods. Details of all tests must be followed closely for good results.
Applications of Oscillographic Polarography to the Determination of Organophosphorus Pesticides. II. A Rapid Screening Procedure for the Determination of Parathion in Some Fruits and Vegetables
Authors: Gajan Raymond J
Published: February 2020

A rapid screening technique is described for polarographic determination of less than 0.1 ppm of parathion residues on some fruits and vegetables. Methyl anthranilate does not interfere. Results compare favorably with those by two other procedures. The technique shows promise for use with other pesticides possessing nitro groups.
Determination of Parathion, Methyl Parathion, EPN, and Their Oxons in Some Fruit and Vegetable Crops
Authors: Coffix D E , Mckixley W P
Published: February 2020

Parathion, methyl parathion, EPN, and their corresponding oxons are extracted from plant material with acetonitrile, cleaned up by elution from polyethylene-coated alumina with a 40% acetonitrile solution, partitioned between chloroform and water, and eluted from magnesol with chloroform. Total content is estimated by a spectrophotometric measurement at 400 mμ of the p-nitrophenol produced by alkaline hydrolysis. They can be separated and identified by paper chromatography. The procedure for quantitative estimation after paper chromatographic separation is suitable for quantities of 2—20 μg. This procedure has been applied to organophosphate standards added to lettuce, apples, and strawberries. Recoveries varied from 84 to 100% of the added compound.
Determination of Glyodin Residues on Pears and Peaches
Authors: Kleinman A
Published: February 2020

A collaborative study has been made of the recovery of glyodin added to pears and peaches at levels slightly below and slightly above the tolerance. Recoveries of individual collaborators average from 72 to 112% of added amounts of glyodin. The method is recommended as official, first action for apples and peaches. Study should be continued on peaches and extended to include other fruits subject to the tolerance.
Collaborative Study of Maleic Hydrazide Residue Analysis
Authors: Lane J R
Published: February 2020

With the Naugatuck Chemical Method G-114-A, an expanded laboratory version of the Lane, Gullstrom, and Newell modification of the original Wood method, five collaborators made distilled standard curves (10—200 μg) with maximum variation of + 10% and—4% from an average laboratory curve obtained over several years and with curves of maleic hydrazide distilled from potatoes with maximum variation of + 14% and—9%. Average recoveries of unknowns of duplicate determinations gave a 9 5% confidence limit of 13.5 μg at the 100 μg level, and 6.4 μg at the 25 μg level.
Determination of Fusel Oil in Distilled Spirits
Authors: Schoeneman Robert L
Published: February 2020

The Mathers-Schoeneman modification of the Komarowsky Reaction for fusel oil, using 4-hydroxybenzaldehyde-3-sulfonic acid, has been collaboratively studied in comparison with the official fusel oil method using p-dimethylaminobenzaldehyde. Because of certain advantages of the Mathers-Schoeneman fusel oil method, it is recommended that it be adopted as an alternative official, first action method.
Photometric Determination of Phosphate in Wines
Authors: Nelson Raymond A , Beck John E
Published: February 2020

The collaborative study of the photometric molybdovanadate method for the determination of phosphate in wines, which was adopted as first action last year, has been completed. It is recommended that the method be adopted as official, final action.
Determination of Total Acids in Wines: American Society of Enologists-AOAC Joint Report on Wines
Authors: Guymon J F
Published: February 2020

The organization of the American Society of Enologists and its activities relative to developing new or improved procedures for analysis of wines are reviewed by its liaison officer to the AOAC. A modification of the official method for acidity in wines has been collaboratively studied and its adoption is recommended.
Fusel Oil Determination by Gas-Liquid Chromatography
Authors: Martin Glenn E , Caggiano Gian , Schlesinger Howard
Published: February 2020

A method was developed for the determination of fusel oil by gas-liquid chromatography. Separation is effected in a ¼” column containing 20% Ucon polar as the liquid phase, on a solid support of Gas Chrom P at isothermal condition 90° C. The method is simple and expeditious, and the amount of each component alcohol can be determined individually.
Sodium and Potassium in Wines and Distilled Spirits
Authors: Meuron Herman J
Published: February 2020

The flame photometric method of Pro and Mathers for sodium and potassium in wines and distilled spirits has been studied by 10 collaborators: 4 government laboratories, 1 private laboratory, 1 distiller, and 3 wineries. The method uses simple dilutions without further treatment or ashing for sample preparation. Wines are diluted from 50 to 200 times with water, and distilled spirits are used straight or diluted up to 5 times with 50% ethanol. Standard curves are prepared; water is used for comparison with wines and 50% ethanol is used when determining distilled spirits. The method is rapid and convenient and is adaptable to any type of flame spectrophotometer. The collaborative results indicate that the method is satisfactory within the accuracy needed for use by regulatory and enforcement agencies and by the wine and distilled spirits manufacturers.
Colorimetric Determination of Urea in Feeds
Authors: Potts T J
Published: February 2020

A collaborative study was undertaken this year on the DMAB method for the colorimetric determination of urea in dry corn samples, which was compared with method 22.023-22.024. The DMAB method uses p-dimethylami-nobenzaldehyde as the color producer for spectrophotometry measurement. Mean values showed excellent recovery by both the official procedure and the DMAB procedure. Over-all standard deviation and coefficient of variation for all three dry corn samples containing urea indicated greater precision and accuracy by the DMAB procedure; collaborators expressed preference for this method. Further work is recommended to finalize the determination of urea in feeds.
Collaborative Study of the Determination of Ethoxyquin in Feeds
Authors: Gordon Richard S
Published: February 2020

The previously reported method for the determination of Santoquin (ethoxyquin) in feeds yielded highly reproducible results; duplicate determinations varied ± 2.6% from the mean. The use of different fluorometers gave a greater range of background values than previously. However, the average values obtained from all laboratories using the method was 99.9% of the true value over the entire range of Santoquin concentrations (0—200 ppm) studied, and 97.2% of the absolute value in the range of Santoquin concentration (100—150 ppm) ordinarily encountered in mixed feed. The standard deviation from all laboratories in the 100—150 ppm range is about 7.4% of the value observed. It is recommended that the method as previously reported be adopted as official, first action and the task force expanded to include more laboratories with a still greater variety of fluorometers before recommending that the method be adopted as official, final action.
Determination of Phosphate Composition of Stock Food Calcium Phosphate
Authors: Bernhart D N , Chess W B
Published: February 2020

A method has been developed to determine the phosphate composition of commercial stock food grade calcium phosphates with an over-all accuracy of ± 2% absolute. It is based on the EDTA solubility of all the o-phosphates, water-solubility of monocalcium phosphate, thermal conversion of dicalcium phosphate to pyrophosphate, and thermal stability of tricalcium phosphate. Results are given for both known and commercial samples.
A More Accurate Method for Determination of Caffeine in Decaffeinated Coffee
Authors: Yeransian J A , Kadin H , Borker E , Stefanucci A
Published: February 2020

An interfering, non-caffeine, nitrogen-containing material has been found in the final micro Bailey-Andrew extract of caffeine in decaffeinated coffee. This material has been identified as a polypeptide or polypetides with proline, leucine, and valine the predominant amino acids. These interfering materials tend to give high results when decaffeinated coffees are analyzed by the micro Bailey-Andrew procedure. A new chromatographic method, utilizing acid-Celite and alumina columns for purification and UV determination of the caffeine, is described. This method gives a more accurate measure of the caffeine content than the micro Bailey-Andrew. It has been applied successfully to decaffeinated green, roasted, and instant coffees.
Historical AOAC Data on Four FEMA Samples of Vanilla Extracts
Authors: Wendt Arthur S
Published: February 2020

Collaborative studies were made using AOAC methods for alcohol, lead numbers, resins, and vanillin on one genuine pure single fold vanilla extract and three prepared adulterated extracts. It is shown that these classical methods for the analysis of vanilla extract are not adequate to detect a well prepared adulterated vanilla extract.
Variation in Quantity of Methanol Recovered from Raisins
Authors: Brown M Alice , Woodward James R , DeEds Floyd
Published: February 2020

The amount of naturally occurring methanol in fruit must be known so that the quantity left as fumigation residue can be determined. In a study of methanol content of raisins, which had given inconsistent results, the raisins were subjected to different conditions of treatment immediately prior to methanol determination. Conditions that favored pectin esterase activity gave higher values for methanol content than conditions known to inactivate enzymes. Evidence was also obtained that both chemical and enzymic hydrolysis of methyl ester groups of pectic materials occur during analysis.
Lemon Juice Composition. I. Characterization of California-Arizona Lemon Juice by Its Total Amino Acid and l-Malic Acid Content
Authors: Vandercook Carl E , Rolle Laurence A , Ikeda Robert M
Published: February 2020

The total amino acid and i-malic acid content of 61 samples of commercial California-Arizona lemon juice and lemon juice concentrates were studied. In characterizing these juices, relationships were observed between the natural citric acid content and the amounts of their total amino acids and l-malic acid. Total amino acids were determined by formol titration, while the l-malic acid was determined by measuring the optical rotation of a uranylmalate complex. Paper chromatograms of the individual amino acids are used to supplement these methods of analysis for characterizing lemon juice.
Lemon Juice Composition. II. Characterization of California-Arizona Lemon Juice by Its Polyphenols Content
Authors: Vandercook Carl E , Rolle Laurence A
Published: February 2020

The total polyphenolics content of 61 samples of California-Arizona lemon juice were determined by measuring their ultraviolet spectra in an alcoholic solution. In characterizing these juices, relationships were observed between total polyphenolics content and citric acid content. Paper chromatograms of the individual polyphenolics are used to supplement the spectral method.
Chick Edema Factor. III. Application of Microcoulometric Gas Chromatography to Detection of Chick Edema Factor in Fats or Fatty Acids
Authors: Firestone David , Ibrahim Walid , Horwitz William
Published: February 2020

A rapid screening test for detecting chick edema factor in fats consists of adsorption chromatography of extracted unsaponifiables on alumina, followed by analysis of specific fractions by a microcoulometric gas chromatograph which is sensitive only to halogens. This chromatographic method appears to be more sensitive than the chick bioassay.

Toxic fat yielded gas chromatographic peaks with retention times relative to aldrin of 5 or more. All samples which failed to reveal those chromatographic peaks have been shown to be nontoxic in the chick bioassay.
Comparison of Methods for Determination of Lysine in Cereals
Authors: Pomeranz Y , Miller B S
Published: February 2020

The lysine contents of 10 milled wheat products and cereal foods were determined by microbiological, enzymatic, two-dimensional paper chromatographic, and ion exchange chromatographic methods. The assay of lysine by two-dimensional paper chromatography produced very low results. The results from the microbiological method were comparable to those by the ion exchange method. The decarboxylase method consistently gave low results which averaged 82% of those obtained by the microbiological assay. Possible reasons for these low results are presented and discussed.
Bioassay of Chick Edema Factor—1962 Collaborative Study
Authors: Flick D F , Winbush James , Friedman Leo
Published: February 2020

The lower limits of sensitivity of the method by Douglass and Flick for the bioassay of the chick edema factor were more clearly delineated by studies this year in which toxic fatty material (TFM) was fed in duplicate trials at 0.00, 0.25, 0.50, 0.75, and 1.00 g per 16 g cottonseed oil, USP. Nine laboratories collaborated in these studies. Results indicated that the following criteria to establish presence of chick edema factor is valid: "t" value exceeds + 1.3, the mean log (pericardial fluid volume X 100) of the negative control group is 1.1460 or less, and the mean log (pericardial fluid volume X 100) of the test group is 1.1461 or more.
Determination of Potassium in Tobacco
Authors: Ogg C L
Published: February 2020

method for potassium in tobacco, based on extraction with 0.5N HCl and flame photometry of the extract, was evaluated by a collaborative test between 12 laboratories. Results indicate that more work on the method is needed. The coefficients of variation for the six samples increased as the per cent potassium increased. The distribution of values for the separate samples indicates that the flame photometry rather than the extraction procedure was responsible for the lack of good precision between laboratories on the samples high in potassium. Modifications are suggested for improving the method.
Elution Column Preparation of Leaf Sample for Flame Photometry. II. Determination of Calcium in Tobacco
Authors: Dobbins James T
Published: February 2020

A simplified method of preparing tobacco samples for calcium determination was sought. Timed leachings of tobacco indicated that cation exchange phenomena operated in systems containing calcium, potassium, tobacco cellulose, and water. Affinities of the cations involved were such that hydrogen ion exchanged with calcium and displaced it into solution. An elutive treatment was developed, based on this property, whereby the readsorption of calcium could be successfully reduced. A radiation buffer technique of flame photometric examination eliminated the effect of potassium interference on calcium determination, allowing calcium and potassium to be run on the same eluate when treated as follows: Tobacco is mixed with acid-washed Celite 545, topped with pure acid-washed Celite 545, and eluted with 3N HCl. The eluate is made to 1000 ml and a portion is withdrawn and compared against standards containing the equivalent amount of acid for potassium determination. A 50 ml aliquot of eluate is then made to 100 ml with sufficient potassium of any convenient concentration, such as 15 ml of 2000 ppm potassium, so as to yield a final solution containing 300 ppm K. Calcium is compared to similarly prepared flame photometry standards.
Petroleum Ether Extractables in Tobacco
Authors: Wickham J E , Blackmore R H
Published: February 2020

Eleven collaborators participated in a study of two methods for the determination of the petroleum ether extractables in tobacco: Method I, a Soxhlet extraction of a 1 g, finely-ground tobacco sample for 3 hours; Method II, a Goldfisch extraction of a 1 g, finelyground tobacco sample for 8 hours. The petroleum ether extract was evaporated on a steam bath until the ether odor disappeared, and the residues were dried in a forced draft oven for 1 hour at 100 ± 1° C. Samples were cooled in a desiccator containing anhydrous CaCl2 before weighing the petroleum ether extractables. Good reproducibility was obtained for both methods on duplicate analyses within laboratories. However, the precision between laboratories was not as good as that within laboratories.
Comparison of Chemical and Microbiological Methods for the Determination of Procaine Penicillin in Premixes and Mixed Feeds
Authors: Katz Stanley E
Published: February 2020

A chemical and a microbiological method of analysis for procaine penicillin in premixes and mixed feeds have been compared. The microbiological assay method was a typical cylinderplate assay procedure. The chemical method was based upon the conversion by base of penicillins to penicilloic acids. In the eight premixes studied, the chemical-to-microbiological ratio of results varied from 0.92 to 1.17. In four mixed feeds, the ratio varied from 0.97 to 1.09. In general, the chemical method yielded slightly higher results than the microbiological method. There was little difference between methods in regard to reproducibility and accuracy.
Microbiological Method for Assaying Nystatin in Animal Feeds
Authors: Pagano Joseph F
Published: February 2020

A microbiological assay procedure for the determination of nystatin2 in animal feeds at levels as low as 2 5 ppm has been developed. The assay procedure and two feed samples were submitted to five collaborating laboratories for evaluation. The results of the collaborative assay study are presented, and it is recommended that the method be adopted as official, first action.
A Quantitative Fluorometric Method for the Determination of Serpasil (Reserpine,® CIBA) in Feeds at the Micro Level
Authors: Tishler F , Sheth P B , Giaimo M B
Published: February 2020

A fluorometric method is described for the determination of reserpine in feeds at the 2.0 (0.0002%), 1.0 (0.0001 %), and 0.2 (0.00002%) ppm levels. The previously reported method for 0.2 ppm has been modified slightly to include 2.0 and 1.0 ppm, each of whose procedures differed from one another and from that of 0.2 ppm. Blended feed samples containing 2.2 and 0.22 ppm of reserpine were analyzed by the collaborating laboratories. Based upon the results received, it is recommended that the proposed procedure be adopted as official, first action.
Acetyl-(para-Nitrophenyl)-Sulfanilamide in Feeds
Authors: Cavett J W
Published: February 2020

The Bratton-Marshall Sulfa Method was adapted i n 1956 to the analysis of APNPS in feed. A collaborative study was made on two samples of feed containing 0.021 and 0.030% APNPS. In this method, the feed sample was extracted with methanol, and an aliquot of the methanol extract was treated with zinc sulfate to precipitate foreign matter. After filtration, an aliquot of the filtrate was deacetylated by making it acid with HC1 and boiling for 1 hour in a water bath. An aliquot of the deacetylated solution was then treated with the Bratton-Marshall reagents, and the amount of APNPS was determined colorimetrically at 540 mμ, using a standard curve. Results were good on the 36 determinations made, and the method for APNPS in feeds is recommended for adoption as official, first action.
Ethopabate in Feeds
Authors: Szalkowski C R
Published: February 2020

A method for ethopabate was submitted to a collaborative study. Unmedicated commercial poultry feeds assayed by this method showed an apparent ethopabate content of 0.2—0.4 ppm; when blended with a premix of ethopabate and amprolium at levels of 2-10 ppm ethopabate and 125-250 ppm amprolium, recoveries obtained ranged from 96 to 105%. In studies of 17 other drugs added, only sulfaquinoxaline and nicarbazin produced high results. This assay method is suitable for the determination of ethopabate in feeds down to levels of 2 ppm.
Diethylstilbestrol Occurrence in Eggs of Subcutaneously Injected Hens
Authors: Umberger Ernest J , Banes Daniel , Kunze Frieda M , Colson Sylvia H
Published: February 2020

Residues of diethylstilbestrol were shown to remain in eggs of laying hens for at least a week after the hens were injected with 25 mg of diethylstilbestrol in oil. Most of the drug occurred in the yolk. The diethylstilbestrol occurs free or in a loosely bound form readily cleaved by mild hydrochloric acid hydrolysis. Results of hydrolysis with beta-glucuronidase indicate that none of the drug occurs in the eggs as the glucuronide.
Separation and Identification of Sodium Salts of Acidic, Propionic, Butyric, and Valeric Volatile Fatty Acids by Paper Chromatography
Authors: Young James A , Schwartzman George
Published: February 2020

A simplified and faster method has been developed to confirm the identity of volatile fatty acids after they have been steam distilled, separated by a silicic acid column, and titrated with NaOH. The method is equally useful for the qualitative detection of propionates in bakery products. The concentrated eluate or distillate is spotted on paper and chromatographed with a mixture of tertiary butanol, n-butanol, and coned NH4OH as the mobile solvent. The unknowns are determined by comparing the Rf values with known sodium salts of the C2-C5 volatile fatty acids.
Comparison of Chemical and Organoleptic Data Obtained on Thawed and Unthawed Frozen Cod, Haddock, and Perch Fillets
Authors: Hillig Fred , Shelton L R , Yates William , Bethea Sammie , Campbell Cynthia M
Published: February 2020

Chemical indexes of decomposition in the drip as well as in the fillets of frozen cod, haddock, and perch are presented. Fillets that were not brined and thawed gave data similar to fillets that were brine-dipped and thawed; indexes in the drip approximate those found in the fillet from which the drip was obtained. Methods of thawing the fillets for organoleptic and chemical examination are discussed and evaluated.
A Specific Bioassay Method for Determining Vapona® Insecticide (DDVP) and Its Residues
Authors: Sun Yun-Pei , Johnson Elmer R
Published: February 2020

A method is described for the specific bioassay of Vapona® insecticide (DDVP) and its residues in the presence of one or a mixture of several insecticides. Less than 1% interference as apparent DDVP may be expected from many insecticides tested. Recoveries of fortified DDVP in crop extracts alone or in combination with 50 ppm of 1—4 cholinesterase-inhibiting insecticides are generally very satisfactory. With small amounts of kerosene, 0.1 ppm of DDVP can be detected in most crop extracts without cleanup.
Factors Affecting Residue-Film Bioassay of Insecticide Residues
Authors: Sun Yun-Pei , Johnson Elmer R , Pankaskie Joe E , Earle Norman W , Sun Juncx-Yi Tung
Published: February 2020

Many factors could affect the mortality of insects and bioassay results: preparation of extracts; method of preparing deposits; loss of volatile insecticides; effect of extractives and additives; age, stage, sex, weight, and species of insects; method of handling insects; size and position of test jars; food used during the test; effect of temperature, humidity, and light; exposure time; contamination of samples; interpretat i on of results; and method of calculating sensitivity. Almost all of these factors affect the mortality of insects, but only a few of them significantly interfere with the final bioassay results if a comparable series of standards is carried on side by side. To obtain more accurate results, all test jars, including the standards, should contain equal amounts of the same extractives; a corresponding standard curve should be prepared from an uncontaminated check for each series of tests; and insects used for each series of tests should be properly sampled from a mixture of several cultures. Within certain limits, the sensitivity of a bioassay may be easily increased by the manipulation of some factors, such as the volume of extract per test jar, age of test insects, size of test container, exposure time, and temperature.
Gas Chromatography of Unsaponifiable Matter. II. Identification of Vegetable Oils by Their Sterols
Authors: Eisner Jerome , Firestone David
Published: February 2020

Corn, cottonseed, olive, milo maize, rice bran, safflower, peanut, soybean oil, and cocoa butter were saponified and the sterols isolated from the unsaponifiable matter on a Florisil column. Gas chromatography of an average of six samples of each oil revealed characteristic patterns which indicated that each oil could be identified when present alone. Three major sterols are present: β-sitosterol, γ-sitosterol, and stigmasterol. β-Sitosterol was the major sterol found to exist in each of the oils investigated. Two other minor sterols were detected, one of which might be α1-sitosterol, an isomer of stigmasterol, and the other a sterol with a saturated side chain.
Microchemical Method for Oxygen
Authors: Steyermakk Al
Published: February 2020

A specific gravimetric procedure was submitted to the collaborators for this year’s study on the determination of oxygen in organic compounds. Three compounds were analyzed: one contained no oxygen, one contained only carbon, hydrogen, and oxygen, and the other was a sulfa compound. The results obtained were good, and the method is recommended as official, first action.
Use of Acetone in the Quinoline Molybdate Reagent for Phosphorus
Authors: Hoffman W M , Wiles C C
Published: February 2020

The quinoline molybdate method has been simplified considerably by the use of a single precipitating solution. This solution, which contains quinoline, sodium molybdate, citric acid, and acetone, is designated the "quimociac" reagent. Acetone in the reagent eliminates the ammonia interference in the precipitation of quinoline phosphomolybdate and makes the method suitable for the determination of available phosphorus in fertilizers.
Nitrogen in Fertilizers: 1962 AOAC Collaborative Study
Authors: Davis H A , Durgin Owen B
Published: February 2020

Studies were continued on methods for determining nitrogen in fertilizers: (1) the reduced iron method, 2.039; (2) the modified reduced iron method of Gehrke, et ah; (3) the chromous reduction method of Nelson; and (4) the chromium powder method of Perrin. Eight collaborators were provided with a 7—7—7 liquid sample, four of the same stock as 1961 samples (Nos. 3, 4, 5, and 6 ) , and a sample of reagent grade KNOs . Collaborative results indicated no "best" method; each method will give equally reliable results from an over-all standpoint. Personal likes or familiarity with a particular technique may produce more consistent results with one method than with another in the individual laboratory; no uniform preference was indicated. Studies of these methods should be continued, and certain editorial changes in terms relating to "organic N" are recommended.
Agricultural Liming Materials: Mechanical Analysis and EDTA Titration
Authors: Gehrke Charles W , Johnson Frank J
Published: February 2020

Mechanical analyses were conducted in this laboratory on burnt lime, hydrated lime, ground marl, and slag. A "wash" sieving procedure for ground limestone was compared with the "dry" sieving method, 1.002. Data show that added clay plus "wetting" of the sample, followed by dry-sieving, results in more material remaining on sieves mesh No. 40 and 100; a washing technique essentially eliminates this effect. The rate of reaction between different soil types and freshly ground dry agricultural limestone or limestone that was aggregated by wetting and drying varies only slightly.
Collaborative Study on Assay of Sulfur Dioxide in Dried Apricots
Authors: Brekke John E
Published: February 2020

The official (Monier-Williams) method for sulfur dioxide determination in food was compared with a new colorimetric method in a collaborative study. Dried apricots were the test material. Recovery of S 0 2 by the colorimetric method was found to be satisfactory The new method gave results not significantly different from the Monier- Williams volumetric assay but significantly different from the Monier-Williams gravimetric assay.
Alginates in Dressings for Foods
Authors: Wiger Oscar R
Published: February 2020

A collaborative study was conducted for the detection of alginates in dressings for foods. The niethod involved precipitation of alginates with acetonealcohol, removal of oil with dioxane, decolorizing with attapulgus clay, and development of color with ferric hydroxide- sulfuric acid reagent. Recoveries were satisfactory from mayonnaise and salad dressing at the 0.5% level; recoveries from french dressing were unsatisfactory. The method is recommended as official, first action for mayonnaise and salad dressing.
Two-Dimensional Paper Chromatography of Vanilla Extracts
Authors: Fitelson J
Published: February 2020

A second collaborative study of this method has been made with 5 samples. No difficulties were experienced with the method, and the results were satisfactory. While a few collaborators failed to detect adulteration in some of the samples, no collaborators judged satisfactory samples as adulterated. Collaborators agree that the method is simple and provides more information than the single dimension paper chromatography test in many cases. The 2-dimension method has been recommended for adoption as official, final action.
Analysis of Ergotamine Tartrate Suppository Preparations
Authors: Alexander Thomas G
Published: February 2020

The official method for the analysis of ergotamine tartrate tablets has been adapted to the analysis of ergotamine tartrate suppository preparations. A collaborative study was conducted on this modified method. The method is recommended for adoption as official, first action.
Spectrophotometric Determination of Heroin Hydrochloride, Methapyrilene Hydrochloride, and Quinine Hydrochloride
Authors: Endriz John D
Published: February 2020

A rapid, accurate spectrophotometric method has been developed for the simultaneous determination of heroin, methapyrilene, and quinine in the presence of diluents commonly found in illicit narcotic samples. The absorbance curves for heroin, methapyrilene, and quinine show that at the points of maximum absorption of methapyrilene at 313 mμ and quinine at 348 mμ, methapyrilene and quinine do not seriously interfere with the maximum absorption of heroin at 280 mμ. Also, methapyrilene in dilute acid solution absorbs only slightly at the quinine maximum of 348 mμ. The common diluents such as lactose, mannitol, and starch usually found in illicit heroin mixtures do not interfere. The procedure described is sufficiently accurate for forensic purposes and has the advantage of speed over the extraction methods.
Determination of Ethisterone by the Potassium Bromide Disk Technique
Authors: Hayden Alma L
Published: February 2020

Results of determining ethisterone by the KBr disk technique are presented. Two mixtures and tablets from 2 commercial sources were analyzed by the Associate Referee and 4 collaborators. In general, the average recoveries agreed, within 4.5%, with the amounts of ethisterone which were added or declared. In most cases, the recoveries from replicate determinations agreed within 3.8%. The method is recommended for adoption as official, first action.
Colorimetric Determination of Bismuth in Bismuth Subsalicylate Oil Suspension
Authors: Pinella Salvatore J
Published: February 2020

A study was made of a colorimetric determination of bismuth in bismuth subsalicylate oil suspension, similar to that of Official Methods of Analysis. The method depends upon the formation of a yellow bismuth-thiourea complex which exhibits maximum absorption at 465 mμ. Sesame oil is removed by ether extraction after HNO3 hydrolysis and the bismuth nitrate formed is converted to bismuth-thiourea complex with 2.5% thiourea solution in HNO3 (1 + 9). The color complex is stable and follows Beer’s law. The method is comparatively specific for bismuth, since only vanadium and antimony give similar color. It is satisfactory at concentrations as low as 50 μg of bismuth in the final solution. Nine collaborators reported favorable results; it is recommended that the method be adopted as official, first action.
Simultaneous Determination of Esters of 2,4-D and 2,4,5-T in Pesticide Formulations
Authors: Milner M P , Holzer F J , Leary J B
Published: February 2020

A simple and reliable method is described for simultaneously determining esters of 2,4-D and 2,4,5-T. After extraction of the sample with chloroform, the chloroform is evaporated and a hexane solution of the residue is passed over a Florisil column to remove interferences. The esters are then eluted from the column with chloroform and measured spectrophotometrically by using that part of the ultraviolet spectrum where difference between 2,4-D and 2,4,5-T makes possible the measurement of both in the presence of each other.
Infrared and Ultraviolet Spectrophotometric Methods for Rotenone
Authors: Rund Robert C
Published: February 2020

Nine collaborators participated in this year’s study, and their results on the official method vs. ultraviolet vs. infrared are presented and interpreted. The unique part of this program was the testing of these methods on resins, circumventing variations introduced by extraction. The spectrophotometric procedures were shown to be suitable for official, first action adoption and were so recommended.