bluuebunny/crossref_metadata_2025_split huggingface dataset:
On formulations of compressible mantle convection
Authors: Gassmöller Rene , Dannberg Juliane , Bangerth Wolfgang , Heister Timo , Myhill Robert 
Published: February 2020

SUMMARY
Mantle convection and long-term lithosphere dynamics in the Earth and other planets can be treated as the slow deformation of a highly viscous fluid, and as such can be described using the compressible Navier–Stokes equations. Since on Earth-sized planets the influence of compressibility is not a dominant effect, density deviations from a reference profile are at most on the order of a few percent and using the full governing equations poses numerical challenges, most modelling studies have simplified the governing equations. Common approximations assume a temporally constant, but depth-dependent reference profile for the density (the anelastic liquid approximation), or drop compressibility altogether and use a constant reference density (the Boussinesq approximation). In most previous studies of mantle convection and crustal dynamics, one can assume that the error introduced by these approximations was small compared to the errors that resulted from poorly constrained material behaviour and limited numerical accuracy. However, as model parametrizations have become more realistic, and model resolution has improved, this may no longer be the case and the error due to using simplified conservation equations might no longer be negligible: while such approximations may be reasonable for models of mantle plumes or slabs traversing the whole mantle, they may be unsatisfactory for layered materials experiencing phase transitions or materials undergoing significant heating or cooling. For example, at boundary layers or close to dynamically changing density gradients, the error arising from the use of the aforementioned compressibility approximations can be the dominant error source, and common approximations may fail to capture the physical behaviour of interest. In this paper, we discuss new formulations of the continuity equation that include dynamic density variations due to temperature, pressure and composition without using a reference profile for the density. We quantify the improvement in accuracy relative to existing formulations in a number of benchmark models and evaluate for which practical applications these effects are important. Finally, we consider numerical aspects of the new formulations. We implement and test these formulations in the freely available community software aspect, and use this code for our numerical experiments.
A decade of sun protection in Australian early-childhood services: analysis of cross-sectional and repeated-measures data
Authors: Hunkin Hugh , Morris Julia�N 
Published: February 2020

AbstractLimiting ultraviolet radiation exposure during early childhood can significantly reduce the risk of developing skin cancer, making early childhood a critical time for sun protection strategies. This study aimed to measure sun protection practices utilized in Australian early-childhood services over the past decade and evaluate the impact of Cancer Council Australia’s SunSmart Early-Childhood Program. Results are presented from cross-sectional and repeated-measures survey data, completed by directors or other staff at randomly sampled early-childhood services in 2008, 2013 and 2018 (N�=�3243). Most sun protection practices were used by a significantly greater proportion of services in 2018 relative to earlier years, such as requiring the use of sunscreen (98.4%), and sun-protective hats (99.7%) and clothing (88.8%). However, only a small and declining proportion of services (16.3%–22.4%) required the use of specific items of sun-protective clothing. SunSmart program members reported enacting significantly more sun protection practices compared to non-members, while new members showed an increase in the use of those practices relative to services whose status did not change (d�=�0.48). The results demonstrate improvements in sun protection in Australian early-childhood settings, and highlight the benefits and limitations of the SunSmart program.
Use of Dacron as an Alternative Carrier for Evaluating Oxidizing Sterilants in the AOAC Sporicidal Test
Authors: McDonnell Gerald , Amato Rasa , Malchesky Paul S , Harrington Stephanie , Muzic David S , Marchant Roger E 
Published: February 2020

Abstract
The AOAC sporicidal method (966.04) recommends the use of porcelain penicylinders and black waxed silk sutures as carriers for demonstrating the sporicidal activity of sterilants. However, the silk carriers are not suitable for evaluating the sporicidal efficacy of oxidizing agents, and an inert polyester material (Dacron) is recommended as an alternative. Dacron provides an equivalent microbial and physical challenge to silk. Microbiologically, both materials demonstrated similar HCl resistance, which is required by the AOAC test, as well as equivalent spore loading and spore wash-off. Electron microscopy showed that both materials present the same braided microstructure, providing an equivalent physical challenge to the test sterilant. Dacron was more consistent than silk, and did not require extraction prior to spore loading. The extraction method for black waxed silk was variable and incomplete, which may compromise the activity of oxidizing sterilants and add to method variability. Silk was also structurally altered in the presence of oxidizing sterilants and increased sterilant degradation. Dacron did not affect the sterilant and was inert in the presence of oxidizing agents. Dacron sutures are proposed as inert alternatives to silk for evaluating the sporicidal efficacy of oxidizing agents.
Determination of Paraffins in Food Simulants and Packaging Materials by Liquid Chromatography with Evaporative Mass Detection and Identification of Paraffin Type by Liquid Chromatography/Gas Chromatography and Fourier Transform Infrared Spectroscopy
Authors: Simal-Gándara Jesús , Sarria-Vidal Miguel , Rijk Rinus 
Published: February 2020

Abstract
A liquid chromatographic method with evaporative mass detection (EMD) is described for the determination of paraffins in food contact materials that do not contain polyolefin oligomers, or paraffins migrating from these materials into fatty food simulants or certain simple foods. A normal-phase column operating at maximum column efficiency separates nonparaffinic and paraffinic materials without resolving the latter into individual components, and EMD is used to quantitate the paraffins. An on-line qualitative method that uses liquid chromatography/gas chromatography with flame ionization detection discriminates between paraffin waxes and oils in food contact materials, food simulants, and certain simple foods; a Fourier transform infrared spectrophotometric qualitative method also discriminates between waxes and oils, but is usually restricted to food contact materials that do not contain polyolefins and to migration experiments with organic solvents as fatty food simulants (with some other fatty food simulants, paraffin type must then be identified in the food contact material).
Measurement of Bromate in Bread by Liquid Chromatography with Post-Column Flow Reactor Detection
Authors: Himata Katsuichi , Noda Masaaki , Ando Susumu , Yamada Yuji 
Published: February 2020

Abstract
This method is suitable for the determination of bromate residues in a variety of baked goods. The peer-verified method trial was performed on white bread, multigrain bread, and coffee cake spiked with known levels of potassium bromate. The analytical portion is extracted with deionized water to remove bromate from the bulk of the baked product. The aqueous extract is carried through a series of steps to remove co-extractives that would interfere with the liquid chromatography (LC) in the determinative step or hasten the deterioration of the LC column. The extract is filtered before passing it through a reversed-phase solid-phase extraction (SPE) column and a cation-exchange column in the silver form to remove lipids and chloride, respectively. Ultrafiltration is then used to remove proteins with molecular weights of &gt;30 000 daltons. Finally, a cation-exchange column in the sodium form is used to remove silver ions from the extract. The determinative step uses LC with a reversed-phase column and an ion-pairing agent in the mobile phase. Detection is based on the post-column reaction of bromate with o-dianisidine to form an oxidation product that is quantitated spectrophotometrically at 450 nm. Overall agreement between the submitting and peer laboratories was quite good. For bromate levels of 10–52 ppb, overall mean recoveries were 76.9 and 78.8% for the submitting and peer laboratories, respectively. The standard deviations were higher for the results of the peer laboratory, probably because of the generally higher level of baseline noise present in the chromatograms. The results demonstrate that the method provides adequate accuracy with low-fat as well as high-fat foods. Bromate at levels as low as 5 ppb (ng/g) can be detected with the method.
Application of Partial Least-Squares Calibration to Phosphorimetric Data for Determination of Polycyclic Aromatic Hydrocarbons in Spiked Environmental Samples
Authors: Carretero A Segura , Galera M Martinez , Blanco C Cruces , García M D Gil , Gutiérrez A Fernández , Vidal J L Martínez 
Published: February 2020

Abstract
A partial least-squares calibration method is proposed, for the first time, for phosphorescence signals. The proposed method is based on the determination of phenanthrene, fluoranthene, and benz[a]anthracene by room temperature phosphorimetry, using microemulsion solutions. The emission and first-derivative emission spectra of the ternary mixtures were tested to perform the calibration matrix. Improved recoveries were found for the prior differentiation step in the analysis of ternary mixtures of these polycyclic aromatic hydrocarbons in road dust samples. The proposed method yielded recoveries ranging from 93.2 to 115.3%, with relative standard deviations of &lt; 6.8%.
Value Assignment of Nutrient Concentrations in Five Standard Reference Materials and Six Reference Materials
Authors: Sharpless Katherine E , Gill Lisa M 
Published: February 2020

Abstract
A number of food-matrix reference materials (RMs) are available from the National Institute of Standards and Technology (NIST) and from Agriculture Canada through NIST. Most of these materials were originally value-assigned for their elemental composition (major, minor, and trace elements), but no additional nutritional information was provided. Two of the materials were certified for selected organic constituents. Ten of these materials (Standard Reference Material® [SRM] 1563 Cholesterol and Fat-Soluble Vitamins in Coconut Oil [Natural and Fortified], SRM 1566b Oyster Tissue, SRM 1570a Spinach Leaves, SRM 1974a Organics in Mussel Tissue (Mytilus edulis), RM 8415 Whole Egg Powder, RM 8418 Wheat Gluten, RM 8432 Corn Starch, RM 8433 Corn Bran, RM 8435 Whole Milk Powder, and RM 8436 Durum Wheat Flour) were recently distributed by NIST to 4 laboratories with expertise in food analysis for the measurement of proximates (solids, fat, protein, etc.), calories, and total dietary fiber, as appropriate. SRM 1846 Infant Formula was distributed as a quality control sample for the proximates and for analysis for individual fatty acids. Two of the materials (Whole Egg Powder and Whole Milk Powder) were distributed in an earlier interlaboratory comparison exercise in which they were analyzed for several vitamins. Value assignment of analyte concentrations in these 11 SRMs and RMs, based on analyses by the collaborating laboratories, is described in this paper. These materials are intended primarily for validation of analytical methods for the measurement of nutrients in foods of similar composition (based on AOAC INTERNATIONAL's fat–protein–carbohydrate triangle). They may also be used as “primary control materials” in the value assignment of in-house control materials of similar composition. The addition of proximate information for 10 existing reference materials means that RMs are now available from NIST with assigned values for proximates in 6 of the 9 sectors of the AOAC triangle. Five of these materials have values assigned for total dietary fiber—the first such information provided for materials available from NIST.
Effect of Temperature and Solvent Composition on Extraction of Fumonisins B1 and B2 from Corn Products
Authors: Lawrence James F , Niedzwiadek Barbara , Scott Peter M 
Published: February 2020

Abstract
Fumonisins B1 and B2 were extracted from naturally contaminated corn products by using different extraction solvent compositions (methanol–water, acetonitrile–methanol–water, ethanol–water, and 100% water) and a range of temperatures from ambient to 150°C. Ground samples of several corn products and 1 rice sample were mixed with an adsorbent material (Hydromatrix™), and the fumonisins were extracted in 2 sequential 5 min static extractions at various temperatures. The combined extracts were cleaned up and analyzed by reversed-phase liquid chromatography with fluorescence detection after o-phthaldialdehyde–mercaptoethanol derivatization. The results showed a clear influence of temperature and solvent composition on recovery of fumonisins from some matrixes. With acetonitrile–methanol–water (1 + 1 + 2) the quantity of fumonisins extracted from naturally contaminated taco shells almost tripled in going from 23° to 80°C, and increased by another 30% when ethanol–water (3 + 7) was used as extraction solvent at 80°C. Similar results were obtained with nacho chips. These effects were less pronounced with cornmeal, and small differences due to temperature and solvent composition were observed for corn flakes and rice. The ethanol–water extraction solvent combinations were specifically evaluated in an effort to use the cheapest, least toxic, and most environmentally friendly solvents for organic residue analysis. At 80°C, ethanol–water combinations performed equally or better than methanol–water (8 + 2) or acetonitrile–methanol–water (1 + 1 + 2), combinations which are commonly used for fumonisin extractions. Even 100% water was successful for extracting fumonisins from the products, except for rice. However, increased amounts of water created technical problems and required an increased amount of Hydromatrix in the samples prior to extraction.
Characterization of Varietal Differences in Essential Oil Components of Hops (Humulus lupulus) by SFC–FTIR Spectroscopy
Authors: Auerbach Rita H , Dost Kenan , Davidson George 
Published: February 2020

Abstract
A supercritical fluid chromatographic method combined with Fourier-transform infrared spectroscopy detection (SFC–FTIR) was developed for determination of varietal differences in essential oil constituents in hops (Humulus lupulus). Infrared spectra (IR) of the major constituents of essential oil of hops were taken as films deposited on AgCl discs and compared with those obtained after chromatographic separation in the IR flow-cell with supercritical carbon dioxide (scCO2). Spectra from AgCl discs were comparable to those in scCO2, but in scCO2 most of the bands appeared approximately 8–10 cm−1 to higher wave numbers. Open-tubular SFC–FTIR analysis of the essential oil of 4 different hop varieties was performed. The SFC–FTIR chromatograms showed differences in the location and relative intensity of the peaks depending on the variety, which was further confirmed by consideration of their FTIR spectra.
Multiresidue Method for the Determination of Residues of 251 Pesticides in Fruits and Vegetables by Gas Chromatography/Mass Spectrometry and Liquid Chromatography with Fluorescence Detection
Authors: Fillion Julie , Sauvé François , Selwyn Jennifer 
Published: February 2020

Abstract
A method is described for the determination of 251 pesticide and degradation product residues in fruit and vegetable samples. Extraction of the sample with acetonitrile is followed by a saltingout step. Co-extractives are removed by passing a portion of the acetonitrile extract through an octadecyl (C18) solid-phase extraction cleanup cartridge and then, in a second cleanup, through a carbon cartridge coupled to an amino propyl cartridge. Determination is by gas chromatography with mass-selective detection in the selected-ion monitoring mode, and by liquid chromatography with post-column reaction and fluorescence detection for N-methyl carbamates. The method has been used for analysis of various fruits and vegetables, such as apple, banana, cabbage, carrot, cucumber, lettuce, orange, pear, pepper, and pineapple. Limits of detection range between 0.02 and 1.0 mg/kg for most compounds. Over 80% of the compounds have a limit of detection of ≤0.04 mg/kg.
Use of a Particle Beam Interface Combined with Mass Spectrometry/Negative Chemical Ionization to Determine Polar Herbicide Residues in Soil by Liquid Chromatography
Authors: Jiménez Juan J , Bernal José L , Del Nozal María J , Martín María T 
Published: February 2020

Abstract
The use of mass spectrometry/negative chemical ionization (MS/NCI), in combination with selected-ion monitoring, allows sensitive and selective determination of polar and thermally unstable herbicide residues by liquid chromatography coupled to a particle beam interface. The method has been applied to the analysis of soil samples for herbicide residues, using various procedures for their extraction and employing matrix-standard calibration to avoid quantitative errors due to transfer of matter through the interface. Data for the fragment ions found in the MS/NCI procedure and chromatograms from analyses of real samples are also presented.
Rapid Target Analysis for Pesticides in Water by Online Coated Capillary Microextraction Combined with Liquid Chromatography and Tandem Mass Spectrometry
Authors: Hartmann Holger , Burhenne Jürgen , Müller Karin , Frede Hans G , Spiteller Michael 
Published: February 2020

Abstract
The applicability of online trace enrichment with custom-made coated capillaries combined with tandem mass spectrometry was demonstrated for the target analysis of selected pesticides (mainly herbicides, e.g., triazines, phenylureas, and acetanilides) in water. The developed method allows rapid determination of several widely used plant protectants within a total analysis time of 11 min. Good linearity (r ≥ 0.995) was obtained for the selected pesticides in the range of 0.050–50 μg/L. The relative standard deviations (RSDs) of the peak areas were ≤3.8% for spiked Milli-Q water (5 μg/L). The RSDs obtained in analyses of spiked (1 μg/L) water samples (brook water, river water, sewage plant effluent) ranged from 2.9 to 6.8%, indicating low influence of the matrix on enrichment and detection. The detection limits, which ranged from 10 to 90 ng/L, fulfilled the requirements of the European regulations for drinking water. The polyacrylate coating of the extraction capillary showed good stability in the presence of water and acetonitrile and allowed ≥100 extractions with 1 capillary.
Detection of Anabolic Residues in Misplaced Implantation Sites in Cattle
Authors: Daxenberger Andreas , Lange Iris G , Meyer Karsten , Meyer Heinrich H D 
Published: February 2020

Abstract
Eight weeks before slaughter, 26 heifers, 2 calves, and 1 steer were implanted with licensed anabolic preparations at off-label injection sites. After slaughter, 24 of 31 implantation sites (77%) were detected. Residual pellets of Revalor H contained a mean of 42.9 mg trenbolone acetate (range 19.8–57.7 mg) and 4.6 mg (1.96–6.45 mg) estradiol, corresponding to 30%(19.8–57.7%) and 32.7% (14.0–46.6%) of the originally applied dose, respectively. In the tissue areas containing residual Revalor H pellets, total residues ranged from 14.8 μg to 12.6 mg trenbolone acetate, 41.7 μg to 1.45 mg trenbolone, and 11.1 μg to 3.39 mg estradiol. The outer tissue areas of the injection sites contained &lt;2 μg hormones. The preparations Synovex H, Finaplix H, Implus S, and Component EC behaved similarly to Revalor H. Residues of Synovex Plus were low, whereas the Compudose silicone rubber contained 58.8%of the implanted dose, but left no significant tissue residues. If implantation sites are processed in meat manufacturing, international threshold levels of the respective substances will be exceeded in tons of meat products.
Determination of Sulfonamides in Swine Meat by Immunoaffinity Chromatography
Authors: Li Jun Suo , Li Xi Wang , Yuan Jian Xiang , Wang Xin 
Published: February 2020

Abstract
A procedure was developed for the preparation of anti-sulfonamide (SA) group-specific antibodies and immunosorbents. Sulfonamide haptens and conjugates were synthesized by building spacer arms on an N1 group of 4-aminobenzensulfonamide. The anti-SA group-specific antibodies and immunosorbents were prepared successfully. After extraction with methanol–water (8 + 2), sulfamonomethoxine, sulfadimethoxine, and sulfaquinoxaline were cleaned up on immunoaffinity columns and determined by reversed-phase liquid chromatography with UV detection at 270 nm. The recoveries from fortified swine meat (10–100 μg/kg) ranged from 70.8 to 94.1%, with coefficients of variation of 3.4–12.9%. Limits of detection were 1–2 μg/kg.
Changes in Content and Composition of Dietary Fiber in Yellow Onions and Red Delicious Apples During Commercial Storage
Authors: Marlett Judith A 
Published: February 2020

Abstract
Changes in pectin composition and solubility are part of the softening process in apples during ripening and postharvest storage. Lignification may also occur with long-term storage. In the United States, apples and onions are harvested once yearly and then stored and marketed for the next 12 months. The changes that occur in the dietary fiber content and composition in Red Delicious apples and yellow Spanish onions during storage were studied, and the loss of fiber in peeled apples was determined. Dietary fiber was extracted by the enzymatic–chemical method of Theander and Westerlund. Storage had no effect on total or insoluble fiber content of apples; Klason lignin concentration was greater in samples stored for 12 months than in those stored for 0, 4, or 8 months. Peeling reduced apple fiber concentration about 25% by decreasing neutral and acidic sugars and Klason lignin in the insoluble fraction. The total fiber content of onions increased with storage, primarily by increasing the insoluble fiber content of uronic acids. The results suggest that the standardized, environmentally controlled storage of apples, as used in Washington State, has little effect on dietary fiber content. In contrast, the less rigorously controlled storage conditions for yellow Spanish onions increases the insoluble fiber fraction and uronic acid content.