bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quality Control of Modified Xiaoyao San Through the Determination of 22 Active Components by Ultra-Performance Liquid Chromatography
Authors: Qin Feng , Huang Jun , Qiu Xinjian , Hu Sihang , Huang Xi 
Published: December 2011

Abstract
A simple, sensitive, and reliable ultra-performance liquid chromatography (UPLC) method has been developed for simultaneous determination of 22 major constituents in modified xiaoyao san (MXS), a multiherbal formula. The chromatographic separation was performed on an ACQUITY UPLC BEH C18 column (150 × 2.1 mm, 1.7 μm, particle size), with an aqueous 0.5% acetic acid and acetonitrile mobile phase gradient. The method was validated for linearity (r2 &gt;0.9937), intraday and interday precision (RSD &lt;8.51%), recovery (91.18–107.73%), LOD (0.02–4.17 ng/mL), and LOQ (0.05–12.50 ng/mL). The established method was successfully applied to quantify the 22 marker compounds in MXS, which provided a useful basis of overall evaluation of the quality of MXS.
Polyacrylic Acid-Modified Alumina for Solid-Phase Extraction and Preconcentration of Trace Iron and Chromium from Plant Samples
Authors: Sabermahani Fatemeh , Taher Mohammad Ali 
Published: December 2011

Abstract
A new method is presented for simultaneous preconcentration of trace Fe(III) and Cr(III) by using polyacrylic acid-alumina as a sorbent. The separation/preconcentration conditions of analytes were investigated, including effect of pH, flow rate, elution conditions, sample volume, and interfering ions. At pH 4, the maximum sorption capacities of Fe3+ and Cr3+ were 8.0 and 13.0 mg/g, respectively, by the column method. The linearity was maintained in the concentration range of 0.175–6.0 × 103 ng/mL for iron and 0.175–8.0 × 103 ng/mL for chromium in the original solution. The RSD values under optimum conditions were ±1.73 and ±1.28% for 2.0 μg/mL Fe and Cr, respectively. The preconcentration factor was 400 for both of the elements, and detection limits were 0.025 and 0.023 ng/mL for Fe and Cr in the original solutions. The proposed method was successfully applied to the determination of trace amounts of Fe and Cr in plant samples.
BIOTECON Diagnostics foodproof®E. coli O157 Detection Kit, 5′ Nuclease for E. coli O157 in Combination with foodproof ShortPrep II Kit
Authors: Junge Benjamin , Grönewald Cordt , Berghof-Jäger Kornelia 
Published: December 2011

Abstract
The method describes the detection of Escherichia coli O157 in food. The method is based on real-time PCR using hydrolysis probes (5′ Nuclease). This advanced PCR method was designed to reduce the time necessary to achieve results from PCR reactions and enable the user to monitor the amplification of the PCR product simultaneously in real time. After DNA isolation using the BIOTECON foodproof® ShortPrep II Kit designed for the rapid preparation of E. coli O157 DNA for direct use in PCR, the real-time detection of E. coli O157 DNA is carried out using the foodproof E. coli O157 Detection Kit. The kit provides primers and hydrolysis probes for sequence-specific detection, convenient premixed reagents, and controls for reliable interpretation of results. For repeatability studies three different foods (egg salad, large bockwurst/frankfurter, and apple juice) were analyzed, chosen from the 15 food groups recommended by the AOAC Research Institute for E. coli O157 detection. From each food, 20 samples were inoculated with a low level (1–10 CFU/25 g) and 20 samples with a high level (10–50 CFU/25 g) of E. coli O157. Additionally, five nonspiked samples were prepared from each food. Depending on the matrix, the food samples were examined with the test kits and compared with the cultural methods according to the U.S. Food and Drug Administration Bacteriological Analytical Manual or the U.S. Department of Agriculture/Food Safety and Inspection Service Microbiology Laboratory Guidebook.
Simple Analysis of Naphthalene, Fluorene, and Anthracene in Whole Blood by Gas Chromatography/Mass Spectrometry After Headspace-Solid Phase Microextraction
Authors: Akdoğan Hatice Ardag 
Published: December 2011

Abstract
A simple and sensitive method for the simultaneous analysis of naphthalene, fluorene, and anthracene in whole blood was developed using headspace-solid-phase microextraction (SPME) and GC/MS. A 0.5 g whole blood sample, 5 μL naphthalene, fluorene, and anthracene (50 μg/mL) as spiked standards, and 0.5 mL sodium hydroxide were placed into a 12 mL vial and sealed rapidly. The vial was immediately heated to 70°C in an aluminium block heater, the needle of the SPME device was inserted through the septum of the vial, and the extraction fiber was exposed to the headspace for 15 min. Afterwards, the compounds extracted by the fiber were desorbed simultaneously by exposing the fiber in the gas chromatograph injection port. No interferences were found, and the time for analysis was about 30 min for one sample. This method was applied to a suicide case in which the victim ingested naphthalene, fluorene, and anthracene.
LC/MS Method Using Cloud Point Extraction for the Determination of Permitted and Illegal Food Colors in Liquid, Semiliquid, and Solid Food Matrixes: Single-Laboratory Validation
Authors: Ates Ebru , Mittendorf Klaus , Senyuva Hamide 
Published: December 2011

Abstract
A cloud point extraction method is reported using LC/MS for the determination of regulated water-soluble food colors (Allura Red, Sunset Yellow, erythrosine, and tartrazine) and banned fat-soluble synthetic azo dyes (Sudan I, II, III, and IV; Red B; 7B; Black B; Red G; Metanil Yellow; and Rhodamine B). The extraction of all 14 colors was carried out with cloud point extraction using the nonionic surfactant Triton X 114. Optimized conditions for cloud point extraction were 3% Triton X 114 (w/v), 0.1 M ammonium acetate, and heating at 50°C for 30 min. This approach proved effective in giving quantitative recoveries from a diverse range of food matrixes, and optimized LC gave baseline chromatographic separation for all colors including Sudan IV and Red B. Single-laboratory validation was performed with spiking into liquid matrixes (wine and homemade wine), semiliquid matrixes (sauce and homemade paprika paste), and solid matrixes (spice and homemade chili powder) using the respective blank matrixes for matrix-matched calibration. The LOQ values for water-soluble colors were in the range of 15–150 mg/kg, and for the fat-soluble colors, 0.1–1.5 mg/kg. The mean recovery values were in the range of 69.6–116.0% (except Allura Red and Sunset Yellow in wine, for which recoveries were lower). The mean RSDs for colors were in the range of 4.0–14.8%. A small survey was conducted of samples of confectionery products, dried fruits, wines, bitter sodas, juices, sauces, pastes, and spices, which demonstrated the applicability of the method to a diverse selection of real food samples. Allura Red was detected in strawberry jelly and Sunset Yellow in artificial saffron.
Reveal®E. coli 2.0 Method for Detection of Escherichia coli O157:H7 in Raw Beef
Authors: Hoerner Rebecca , Feldpausch Jill , Gray R Lucas , Curry Stephanie , Lewis Paul , Tolan Jerry , Goldy Tim , Klein Frank , Neiditch Barry , Hosking Edan , Norton Paul , Rice Jennifer , Mozola Mark N 
Published: December 2011

Abstract
Reveal®E. coli 2.0 is a new lateral-flow immunodiagnostic test for detection of E. coli O157:H7 and O157:NM in raw beef trim and ground beef. Compared with the original Reveal E. coli O157:H7 assay, the new test utilizes a unique antibody combination resulting in improved test specificity. The device architecture and test procedure have also been modified, and a single enrichment protocol was developed which allows the test to be performed at any point during an enrichment period of 12 to 20 h. Results of inclusivity and exclusivity testing showed that the test is specific for E. coli serotypes O157:H7 and O157:NM, with the exception of two strains of O157:H38 and one strain of O157:H43 which produced positive reactions. In internal and independent laboratory trials comparing the Reveal 2.0 method to the U.S. Department of Agriculture–Food Safety and Inspection Service reference culture procedure for detection of E. coli O157:H7 in 65 and 375 g raw beef trim and ground beef samples, there were no statistically significant differences in method performance with the exception of a single internal trial with 375 g ground beef samples in which the Reveal method produced significantly more positive results. There were no unconfirmed positive results by the Reveal assay, for specificity of 100%. Results of ruggedness testing showed that the Reveal test produces accurate results even with substantial deviation in sample volume or device incubation time or temperature. However, addition of the promoter reagent to the test sample prior to introducing the test device is essential to proper test performance.
Spectrofluorimetric Determination of Some Water-Soluble Vitamins
Authors: Mohamed Abdel-Maaboud I , Mohamed Horria A , Abdel-Latif Niveen M , Mohamed Marwa R 
Published: December 2011

Abstract
Two simple and sensitive spectrofluorimetric methods were developed for determination of three water-soluble vitamins (B1, B2, and B6) in mixtures in the presence of cyanocobalamin. The first one was for thiamine determination, which depends on the oxidation of thiamine HCl to thiochrome by iodine in an alkaline medium. The method was applied accurately to determine thiamine in binary, ternary, and quaternary mixtures with pyridoxine HCl, riboflavin, and cyanocobalamin without interference. In the second method, riboflavin and pyridoxine HCl were determined fluorimetrically in acetate buffer, pH 6. The three water-soluble vitamins (B1, B2, and B6) were determined spectrofluorimetrically in binary, ternary, and quaternary mixtures in the presence of cyanocobalamin. All variables were studied in order to optimize the reaction conditions. Linear relationship was obeyed for all studied vitamins by the proposed methods at their corresponding λexc or λem. The linear calibration curves were obtained from 10 to 500 ng/mL; the correlation ranged from 0.9991 to 0.9999. The suggested procedures were applied to the analysis of the investigated vitamins in their laboratory-prepared mixtures and pharmaceutical dosage forms from different manufacturers. The RSD range was 0.46–1.02%, which indicates good precision. No interference was observed from common pharmaceutical additives. Good recoveries (97.6 ± 0.7–101.2 ± 0.8%) were obtained. Statistical comparison of the results with reported methods shows excellent agreement and indicates no significant difference in accuracy and precision.
Suitability of an Orbitrap Mass Spectrometer for the Screening of Pesticide Residues in Extracts of Fruits and Vegetables
Authors: Alder Lutz , Steinborn Angelika , Bergelt Sebastian 
Published: December 2011

Abstract
For about 500 pesticides, the sensitivity of a benchtop high-resolution mass spectrometer using the Orbitrap for mass separation was compared to that of a widely used (low-resolution) tandem mass spectrometer. Both instruments were coupled to LC and used electrospray ionization. The selectivity of the Orbitrap in the full-scan acquisition mode without fragmentation was evaluated at a resolution of 100 000 full width at half maximum for all pesticides detectable with sufficient sensitivity. For this purpose, quasimolecular ions were extracted within 5 ppm windows from total ion chromatograms of two types of extracts of cucumber, lemon, wheat flour, raisin, and tea. In each of the obtained reconstructed ion chromatograms (individual chromatograms for 500 pesticides, each pesticide in 10 different extracts) the sum of signals not arising from the analyte was used to get a measure on selectivity. In addition, the target analyte list was checked for ions of similar mass. The influence of matrix on the ability to detect low concentrations of fortified pesticides was also studied, with the help of spiked extracts. This part of the survey tested whether analyte peaks were lost because of insufficient mass resolution or an early closing C-Trap (used to control the ion current into the Orbitrap). Finally, the stability of the ion ratio [M+H]+/[M+Na]+ was tested, which may be helpful to confirm the identity of an analyte.
Functionalization of Nanostructured Hematite Thin‐Film Electrodes with the Light‐Harvesting Membrane Protein C‐Phycocyanin Yields an Enhanced Photocurrent
Authors: Bora Debajeet K. , Rozhkova Elena A. , Schrantz Krisztina , Wyss Pradeep P. , Braun Artur , Graule Thomas , Constable Edwin C. 
Published: December 2011

AbstractThe integration of light‐harvesting proteins and other photosynthetic molecular machinery with semiconductor surfaces plays an important role in improving their performance as solar‐cell materials. Phycocyanin is one such protein that can be employed for this purpose. Phycocyanins have light‐harvesting properties and belong to the phycobilisome protein family. They are present in cyanobacteria, which capture light energy and funnel it to reaction centers during photosynthesis. Here, a way of increasing the photocurrent of hematite by covalent cross‐coupling with phycocyanin is reported. For this, a hematite–phycocyanin integrated system is assembled by consecutive adsorption and cross‐coupling of protein molecules, separated by an agarose layer and a linker molecule, on the top of a mesoporous hematite film. The hematite–phycocyanin assembly shows a two‐fold increased photocurrent in comparison with pristine hematite film. The increase in the photocurrent is attributed to the enhanced light absorption of the hematite film after integration with the protein, as is evident from the UV–vis spectra and from the photocurrent‐action spectrum. The assembly shows long‐term stability and thus constitutes a promising hybrid photoanode for photo‐electrochemical applications.
Smart and structural thermosets from the cationic copolymerization of a vegetable oil
Authors: Meiorin Cintia , Aranguren Mirta I. , Mosiewicki Mirna A. 
Published: December 2011

AbstractCopolymers based on tung oil (TO) and presenting a very wide range of properties were obtained. Depending on the chemical composition, materials fitted for structural or functional applications were prepared. The use of divinylbenzene (DVB) as a comonomer in the cationic polymerization of the triglyceride allowed us to obtain polymers with a high thermal stability in an ample temperature range and with a room‐temperature modulus close to 1 GPa for percentages of TO up to 40 wt % styrene (St) as a partial replacement of DVB in a copolymer containing 50 wt % TO resulted in a material with shape‐memory behavior with switch temperatures in the range 25–40°C. The mechanical properties and shape‐memory behavior of copolymers with different chemical compositions were analyzed. It was observed that an increase in the DVB content increased the glass‐transition temperature and modulus, which was associated with an increase in the crosslinking density and the contribution of the rigid aromatic structure of the comonomer. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Effect of acrylic monomer content on the properties of waterborne poly(urethane‐urea)/acrylic hybrid materials
Authors: Son Su‐Jin , Kim Ki‐Beom , Lee Young‐Hee , Lee Dong‐Jin , Kim Han‐Do 
Published: December 2011

AbstractStable waterborne poly(urethane‐urea) (WBPU; soft segment content: 57%; dimethylol propionic acid: 19 mol %/5.8 wt %)–polyacrylate(methyl methacrylate/n‐butyl acrylate) (weight ratio: 4/1) hybrid latex (emulsions) with different acrylic contents [0, 10, 20, 30, and 40 wt % based on poly(urethane‐urea)] and without external surfactant were successfully prepared by in situ polymerization during a prepolymer mixing process. However, the as‐polymerized hybrid latex containing 50 wt % of acrylic monomer content was found to be unstable, indicating that about 50 wt % of acrylic monomer content was beyond the limit value of self‐emulsifying ability of WBPU anionomer prepared in this study. The breadth of particle size distribution of hybrid latex increased markedly from 20–75 to 55–275 nm with increasing acrylic monomer content from 0 to 40 wt %. The pristine WBPU and hybrid latex samples containing 10, 20, and 30 wt % of acrylic monomer showed unimodal distributions, whereas the hybrid sample having 40 wt % acrylic monomer content displayed a bimodal distribution with the broadest breadth. As acrylic monomer content increased, the yield point of stress–strain curve, hardness, glass transition, and water resistance of hybrid film samples increased, whereas their abrasion resistance, elongation at break, and elasticity decreased. The tensile strength of hybrid film samples (10–30 wt % of acrylic monomer content) was almost the same as that of pristine WBPU film sample, indicating the intimate molecular mixing between poly(urethane‐urea) and polyacrylate molecules in hybrids. However, the hybrid sample having 40 wt % acrylic monomer showed significantly diminished performance, which might be due to the deviation from intimate molecular mixing. From these results, the optimum acrylic monomer content was found to be about 30 wt %, which realized reasonably advantages of both poly(urethane‐urea) and acrylic polymer. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Rheokinetic of a gelled resol resin curing by dynamic‐temperature rheometry based on rectangular torsion strain
Authors: Domínguez J. C. , Oliet M. , Alonso M. V. , Rojo E. , Rodríguez F. 
Published: December 2011

AbstractThe rheological behavior of a phenolic resol resin during its curing process was studied through a rheological dynamic‐temperature analysis. Two heating ramps from 0 to 120°C (1°C/min) and from 0 to 150°C (5°C/min) were performed. The resin's complex viscosity data were obtained by applying a rectangular torsion strain. The overall change of complex viscosity with temperature was due to a combination of thermal softening, described by the Andrade equation, and the resin crosslinking process. The four‐ and six‐parameter Arrhenius rheokinetic model was applied to the profiles obtained for the resin's complex viscosity, and the viscous flow and activation energies of curing kinetics were established. Two calculation methods are proposed to obtain the flow and curing parameters of the material. The six‐parameter Arrhenius model was more suitable for predicting changes in the resin's complex viscosity, obtaining an activation energy of ∼ 38.0 kJ/mol for the resol resin curing process. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
The pathophysiologic role of the protein kinase Cδ pathway in the intervertebral discs of rabbits and mice: In vitro, ex vivo, and in vivo studies
Authors: Ellman Michael B. , Kim Jae‐Sung , An Howard S. , Kroin Jeffrey S. , Li Xin , Chen Di , Yan Dongyao , Buechter Doug D. , Nakayama Keiichi , Liu Bo , Morgan Stephanie , Im Hee‐Jeong 
Published: December 2011

AbstractObjectiveProtein kinase Cδ (PKCδ) activation has been shown to be a principal rate‐limiting step in matrix‐degrading enzyme production in human articular chondrocytes. The aim of this study was to assess the role of the PKC pathways, specifically PKCδ, in intervertebral disc tissue homeostasis.MethodsUsing in vitro, ex vivo, and in vivo techniques, we evaluated the pathophysiologic role of the PKCδ pathway by examining 1) proteoglycan deposition, 2) matrix‐degrading enzyme production and activity, 3) downstream signaling pathways regulated by PKCδ, and 4) the effect on in vivo models of disc degeneration in genetically engineered PKCδ‐knockout mice.ResultsStudies of pathway‐specific inhibitors revealed a vital role of the PKCδ/MAPK (ERK, p38, JNK) axis and NF‐κB in disc homeostasis. Accordingly, in an in vivo model of disc injury, PKCδ‐knockout mice were markedly resistant to disc degeneration.ConclusionSuppression of the PKCδ pathway may be beneficial in the prevention and/or treatment of disc degeneration. The results of this study provide evidence for a potential therapeutic role of pathway‐specific inhibitors of the PKCδ cascade in the future.
Magnetotransport Properties and Kondo Effect Observed in a Ferromagnetic Single‐Crystalline Fe1−xCoxSi Nanowire
Authors: Lee Sunghun , In Juneho , Chang Jung‐Won , Seo Kwanyong , Jung Myung‐Hwa , Kim Jinhee , Kim Bongsoo 
Published: December 2011

AbstractWe report unconventional magnetotransport properties of an individual Fe1−xCoxSi nanowire. We have studied the dependence of the resistivity on the angle between the directions of the magnetization and electrical current below the Curie temperature (TC). The observed anisotropic magnetoresistance (MR) ratio is negative, thereby indicating that the conduction electrons in a minority spin band of the Fe1−xCoxSi nanowire dominantly contribute to the transport. Unlike typical ferromagnets, positive MR is observed in the overall temperature range. MR curves are linear below TC and show a quadratic form above TC, which can be explained by the change of density of states that arises as the band structures of the Fe1−xCoxSi nanowire shift under a magnetic field. The temperature dependence of the resistivity curve is sufficiently explained by the Kondo effect. The Kondo temperature of the Fe1−xCoxSi nanowire is lower than that of the bulk state due to suppression of the Kondo effect. The high single crystallinity of Fe1−xCoxSi nanowires allowed us to observe and interpret quite subtle variations in the prominent intrinsic transport properties.
Nanoporous Carbon Materials for Electrochemical Sensing
Authors: Poh Hwee Ling , Pumera Martin 
Published: December 2011

AbstractNanoporous carbon materials are highly important materials for a wide array of applications. Here we show that nanoporous carbon can act as highly active materials for electrochemical sensing. We observed that nanoporous carbon material exhibits a faster heterogeneous electron transfer than graphite and pure carbon nanotubes. Nanoporous carbon exhibits a superior electrochemical performance for sensing of important biomarkers such as dopamine, ascorbic acid, uric acid, NADH, DNA bases, and forensic‐related compounds such as nitroaromatic explosives.
Reaction of Acetals with Various Carbon Nucleophiles under Non‐Acidic Conditions: CC Bond Formation via a Pyridinium‐Type Salt
Authors: Fujioka Hiromichi , Yahata Kenzo , Hamada Tomohito , Kubo Ozora , Okitsu Takashi , Sawama Yoshinari , Ohnaka Takuya , Maegawa Tomohiro , Kita Yasuyuki 
Published: December 2011

AbstractMild substitution reactions of acetals with carbon nucleophiles via the pyridinium‐type salts generated by the treatment of acetals with TESOTf‐2,4,6‐collidine or 2,2′‐bipyridyl have been developed. Various carbon nucleophiles, such as organocuprates, silyl enol ethers, enamines, etc., reacted with the pyridinium‐type salts to give the corresponding substituted products in good yields. The reactions proceeded under very mild conditions (non‐acidic conditions) and thus acid‐sensitive functional groups can be tolerated during the reaction. In addition, only an acetal can form the pyridinium‐type salt and react with nucleophiles in the presence of a ketal. This unusual selectivity is in contrast to general methods conducted under acidic conditions.
Identification of NWP humidity biases using high‐peaking water vapour channels from IASI
Authors: Hilton F. I. , Newman S. M. , Collard A. D. 
Published: December 2011

AbstractHigh‐peaking water vapour channels from the Infrared Atmospheric Sounding Interferometer (IASI) have been used to diagnose biases in the Met Office short‐range forecasts of upper tropospheric humidity during the Joint Airborne IASI Validation Experiment (JAIVEx) field campaign. These biases are compared with those from the European Centre for Medium‐Range Weather Forecasts (ECMWF). The Met Office forecasts are found to be too dry relative to IASI observations and in comparison with ECMWF forecasts globally. IASI is shown to be a useful tool for investigating such biases, and subsequent changes to the Met Office data assimilation scheme have successfully reduced this forecast bias. © 2011 Royal Meteorological Society and British Crown copyright, the Met Office