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Different Batches (different + batch)
Selected AbstractsFS01.3 Disperse (yes), orange (yes), 3 (no): what do we test in textile dye dermatitis?CONTACT DERMATITIS, Issue 3 2004Christophe J Le Coz Introduction:, Patients sensitized to para-phenylenediamine (PPD) have a high degree of patch test reactivity to Disperse Orange 3 (DO3), and a lesser one to Disperse Red 1 and Red 17. Two successive patients positive to PPD, Disperse Red 1 and 17, negative to DO3 were real eye-openers for our considerations about purity of our current allergen DO3. Materials and methods:, We realized comparative thin-layer chromatography (TLC), with DO3 from Chemotechnique®(DO3-Chem) and Trolab®(both extracted from petrolatum), and "pure" DO3 from two chemical providers. TLC clearly indicated that DO3-Chem was not DO3. HPLC analysis with pure DO3 from Chemotechnique® and comparison of structures by NMR with samples of DO3, revealed that DO3-Chem was Disperse Orange 31 (DO31). In addition, signals through the GERDA network allowed the collection of test materials and observations. Among other members, only 2 used DO3-Chem (from 2 different batches) that was DO31 too, according to TLC Results: According to their data, they observed no or a lower reactivity to DO3 than expected (4 patients DO3-Chem + among 23 PPD+ e.g.). Finally, the error was proved to be due to the provider of the dye to Chemotechnique®, who likely deleted the 1 of Disperse Orange 31 on his packaging. Discussion:, Chemical structure of DO31 indicates a possible in vivo hydrolysis into nitroaniline and a second compound, a substituted PPD derivative that clearly does not frequently react in PPD positive patients. Like drugs, patch tests are submitted to post-commercialization controls. In addition to allergens providers who should enhance their quality controls, dermato-allergologists have to be vigilant, and must active networks when they observe a rare bird. [source] Geographic variation in the field response of male European pine sawflies, Neodiprion sertifer, to different pheromone stereoisomers and estersENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2000O. Anderbrant Abstract The European pine sawfly, Neodiprion sertifer (Geoffroy) (Hymenoptera: Diprionidae), is a widespread and economically important forest insect. The sex pheromone communication system of this species has been previously investigated in North America, Japan and Europe, with the acetate or propionate of the alcohol (2S,3S,7S)-3,7-dimethyl-2-pentadecanol (diprionol) shown to be the main pheromone component. In some locations, male attraction either increased or decreased by the addition of the (2S,3R,7R)-diprionyl acetate isomer. However, these studies were made with different batches of synthetic pheromones, with different types of traps and according to different procedures, so the observed differences might not reflect true geographic variation. Here we investigate the geographic pattern of male sawfly response by using identical chemicals, traps and experimental procedures at eight field sites ranging from Japan in the east to Canada in the west. We found an increased inhibitory effect of the (2S,3R,7R)-isomer from Japan and Siberia to Europe. At the eastern sites, increasing amounts of the (2S,3R,7R)-isomer up to and equal to the amount of the (2S,3S,7S )-isomer, did not influence the trap catch, whereas at sites in Europe, as little as 1% of the (2S,3R,7R)-isomer almost completely inhibited the attraction. The response of the North American population was intermediate. The only site in which the (2S,3R,7R)-isomer was essential for the attraction of males was in Siberia. A similar pattern was found for the (2S,3R,7S)-isomer. Both the acetate and the propionate form of the (2S,3S,7S)-isomer were attractive by themselves in Japan, Europe and North America, and neither the (2S,3R,7S)-isomer nor the (2S,3R,7R)-isomer alone were attractive, in the acetate or propionate form. We discuss the significance of our findings for the development of more efficient monitoring schemes and for the causes of population divergence and speciation in the European pine sawfly. [source] Cytochrome b559 content in isolated photosystem II reaction center preparationsFEBS JOURNAL, Issue 10 2003Inmaculada Yruela The cytochrome b559 content was examined in five types of isolated photosystem II D1-D2-cytochrome b559 reaction center preparations containing either five or six chlorophylls per reaction center. The reaction center complexes were obtained following isolation procedures that differed in chromatographic column material, washing buffer composition and detergent concentration. Two different types of cytochrome b559 assays were performed. The absolute heme content in each preparation was obtained using the oxidized-minus-reduced difference extinction coefficient of cytochrome b559 at 559 nm. The relative amount of D1 and cytochrome b559,-subunit polypeptide was also calculated for each preparation from immunoblots obtained using antibodies raised against the two polypeptides. The results indicate that the cytochrome b559 heme content in photosystem II reaction center complexes can vary with the isolation procedure, but the variation of the cytochrome b559,-subunit/D1 polypeptide ratio was even greater. This variation was not found in the PSII-enriched membrane fragments used as the RC-isolation starting material, as different batches of membranes obtained from spinach harvested at different seasons of the year or those from sugar beets grown in a chamber under controlled environmental conditions lack variation in their ,-subunit/D1 polypeptide ratio. A precise determination of the ratio using an RC1-control sample calibration curve gave a ratio of 1.25 cytochrome b559,-subunit per 1.0 D1 polypeptide in photosystem II membranes. We conclude that the variations found in the reaction center preparations were due to the different procedures used to isolate and purify the different reaction center complexes. [source] Studies on the appearance of skeletal anomalies in red porgy: effect of culture intensiveness, feeding habits and nutritional quality of live preysJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2010M. S. Izquierdo Summary Despite the great interest of red porgy as a new species for Mediterranean aquaculture, its commercial production is constrained by the high incidence of skeletal deformities occurring in this species under culture conditions. Several studies have been conducted to better understand the origin of these anomalies in this species, using different system intensiveness, rotifers enrichment products or rotifers docosahexaenoic acid content. The first study showed that culture intensification increased the number of fish with an extra vertebrae, what was probably related to the different nutritional quality of live preys employed in each treatment, since water temperature, salinity and genetic background were identical for the different batches of fish studied. Total incidence of skeletal abnormalities was higher in the intensive system, particularly cranial abnormalities and kyphosis in the cephalic vertebrae. In both rearing systems the most common skeletal anomalies were vertebral column disorders, lordosis and fused vertebrae, their localization along the column being affected by the culture intensiveness. Rotifer enrichment, predominantly its docosahexaenoic acid content significantly affected deformities occurrence. A marked positive effect of rotifer docosahexaenoic acid content was found on larval survival. X-ray studies denoted elevated levels of bone abnormalities associated, in both trials, to low docosahexaenoic acid content in live preys. Among different anomalies, the presence of fused vertebrae was the most frequent deformity for both rearing trials. A 50% reduction in the number of deformed fish for each type of deformity was obtained when the larvae were fed higher docosahexaenoic acid levels, denoting the important role of this fatty acid in bone development. Further studies are needed to elucidate the importance of essential fatty acids on the development of bone deformities in fish, since the functions of these fatty acids differ among them and can lead to very different effects in fish metabolism, including bone formation. [source] Effects of organic matter and initial carbon,nitrogen ratio on the bioconversion of volatile fatty acids from sewage sludgeJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 7 2008Xiaoling Liu Abstract BACKGROUND: The biodegradable organic matter and the initial carbon,nitrogen ratio can be substantially different in different batches of sewage sludge, which results in a difference in the acidification efficiency of sludge. Using sewage sludge from three different sources, batch tests were performed to analyze the relationship between volatile fatty acids (VFAs) and consumed organic matter, and to investigate the effects of initial carbon,nitrogen (C/N) ratio on the acidification efficiency of sludge. RESULTS: Maximum yields of 152.1 ± 3.5 mg total VFAs-COD per gram volatile solid (VS) added and 22.4 ± 1.2 mg butyric acid-COD g,1 VS added were obtained from the sludge with the highest initial C/N ratio. Statistical analysis indicated that protein was the major substrate for the produced VFAs. The sludge with the least initial C/N ratio (5.01) had the least yield, and only acetic acid, which was also mainly related to protein, was detected. CONCLUSION: The initial carbon,nitrogen ratio was one of the most important factors influencing the distribution patterns of VFAs and the yield of total VFAs produced from sewage sludge. A high C/N ratio could not only improve the yield of total VFAs but also enhance the yield of butyric acid. Copyright © 2008 Society of Chemical Industry [source] Retention of visible implant and visible implant elastomer tags in brown trout in an English chalk streamJOURNAL OF FISH BIOLOGY, Issue 2 2006D. W. Summers Retention of both rigid and new soft standard size visible implant (VI) tags in brown trout Salmo trutta after 6 months varied between 42 and 97% for different batches, with no evidence of increased retention of the new type of tag. The 6 month retention of visible implant elastomer tags (VIE) also varied but with a mean of 96%. The VIE retention gradually declined with time up to 42 months. [source] Instrumental and Expert Assessment of Mahon Cheese TextureJOURNAL OF FOOD SCIENCE, Issue 7 2000J. Benedito ABSTRACT: To improve Mahon cheese texture assessment, the relationship between instrumental and sensory measurements was sought. For that purpose 30 pieces of Mahon cheese from different batches and 2 different manufacturers were examined. Textural characteristics at different curing times were evaluated by uniaxial compression, puncture, and sensory analysis. Significant linear correlations were found between instrumental and sensory measurements. A logarithmic model (Weber-Fechner) fitted data better than a linear one. Only 1 factor was extracted when considering all the instrumental and sensory variables, thus indicating that both sets of measurements are related to the same phenomenon. The best predictors for Mahon cheese sensory attributes were found to be cheese moisture, deformability modulus, and slope in puncture. [source] Estimation of kinetic and mass-transfer parameters for cellulose nitrationAICHE JOURNAL, Issue 10 2006I. V. M. Barbosa Abstract When nitrocellulose is used in the production of gun powders and rocket/missile propellants, rigid control of the cellulose nitration reaction is necessary. Nitrogen content is, by far, the most important parameter to be controlled and only off-line measurements can be performed for that. Although cellulose is a natural polymer whose characteristics may vary, the final product must have its nonuniformities compensated by blending of different batches. In this work, kinetic and mass-transfer parameters are nonlinearly fitted using typical nitration experiments. The required mathematical modeling is carried out using a continuous mixtures approach, which depends only on structural descriptions of the cellulose. The model leads to an algebraic-integro-differential population balance system of equations, solved with an approximant built with block-pulse functions. © 2006 American Institute of Chemical Engineers AIChE J, 2006 [source] CURRENT-STATUS SURVIVAL ANALYSIS METHODOLOGY APPLIED TO ESTIMATING SENSORY SHELF LIFE OF READY-TO-EAT LETTUCE (LACTUCA SATIVA)JOURNAL OF SENSORY STUDIES, Issue 2 2008MABEL ARANEDA ABSTRACT The objective of the present work was to develop a method for predicting sensory shelf life for situations in which each consumer evaluates only one sample corresponding to one storage time. This type of data is known as current-status data in survival analysis statistics. The methodology was applied to estimate the sensory shelf life of ready-to-eat lettuce (Lactuca sativa var. capitata cv."Alpha"). For each of six storage times, 50,52 consumers answered yes or no to whether they would normally consume the presented sample. The results were satisfactory, showing that the methodology can be applied when necessary. The Weibull model was found adequate to model the data. Estimated shelf lives ± 95% confidence intervals were 11.3 ± 1.2 days and 15.5 ± 0.9 days for a 25% and a 50% consumer rejection probability, respectively. PRACTICAL APPLICATIONS When considering shelf-life evaluations by consumers, the first idea is to have each consumer evaluate six or seven samples with different storage times in a single session. To do this, a reverse storage design is necessary, and in the case of a product such as lettuce, it would lead to different batches being confused with storage times. The methodology proposed in this article avoids this problem by having each consumer evaluate a single sample. Another issue with consumers tasting several samples in a single session is how representative this situation is of real consumption. The present methodology allows for a consumer to take home, e.g., a bottle of beer with an established storage time, and later collecting the information as to whether they found the beer acceptable or not. This is a situation much closer to real consumption. [source] Determination of gastrodin and vanillyl alcohol in Gastrodia elata Blume by pressurized liquid extraction at room temperatureJOURNAL OF SEPARATION SCIENCE, JSS, Issue 13 2007Eng Shi Ong Abstract Pressurized liquid extraction (PLE) at room temperature with a laboratory-assembled system was applied for the extraction of gastrodin (GA) and vanillyl alcohol (VA) in Gastrodia elata Blume. The proposed system setup for this current work was simpler as no heating and backpressure regulator was required. Extraction with PLE was carried out dynamically at a flow rate of 1.5 mL/min, at room temperature, under an applied pressure of 10,20 bars with an extraction time of 40,50 min. The extraction efficiencies of the proposed method using 20% aqueous ethanol were compared with heating under reflux using organic solvents such as methanol and ethanol/water (20:80) for different batches of medicinal plant materials. For the determination of GA and VA in G. elata Blume, the extraction efficiencies of PLE at room temperature were observed to be comparable with heating under reflux. The method precision was found to vary from 1.6 to 8.6% (RSD, n = 6) on different days. The marker compounds present in the various medicinal plant extracts were determined by gradient elution HPLC and HPLC/MS/MS. Our work demonstrated the possibility of implementation of PLE at room temperature and the advantages of minimizing the use of organic solvents in the extraction process. [source] Sensitization to petrolatum: an unusual cause of false-positive drug patch-testsALLERGY, Issue 9 2004G. Ulrich We report on an unexpected sensitization to petrolatum diagnosed with the occurrence of multiple nonrelevant and false-positive drug patch-tests performed while investigating a patient suffering from many cutaneous adverse drug reactions. All the positive drug patch-tests were prepared with GILBERT® vaseline. This petrolatum reaction is positive as it was tested with five other brands of petrolatums a few months later. As the same petrolatums, but from different batches were tested, patch-tests with GILBERT® petrolatum were doubtful, while other petrolatums were positive. White petrolatum is a mixture of semisolid hydrocarbons of the methane series. The sensitizing impurities of petrolatum are polycyclic aromatic hydrocarbons, e.g. phenanthrene derivatives. The purity of petrolatum depends on both the petroleum stock and on the production and packaging methods. Even if rare, contact sensitization to petrolatum can disturb the interpretation of drug patch-tests. It is necessary in the interpretation of drug patch-tests to test both in petrolatum and other vehicles and with all the different petrolatums used in preparing the material for drug patch-tests. So, it is essential to advise the patients sensitized to petrolatum to remove all the topical drugs, such as all the cosmetics, which contain petrolatum in their formulation. [source] Effects of different batches of Neoparamoeba perurans and fish stocking densities on the severity of amoebic gill disease in experimental infection of Atlantic salmon, Salmo salar L.AQUACULTURE RESEARCH, Issue 10 2010Philip B B Crosbie Abstract Currently, there are two methods of inducing laboratory-based amoebic gill disease (AGD) in Atlantic salmon, Salmo salar L.: cohabitation with infected fish or exposure to a suspension of amoebae. Amoebic gill disease cannot be induced with cultured amoebae; therefore, the only source of the infective organism is salmon with the disease. For experimental purposes and to maintain pathogen supply, salmon are kept in an infection tank and amoebae are isolated from salmon once the disease establishes. In this way, discrete batches of amoebae are collected periodically. This study investigated the infective ability of different batches of amoebae. Furthermore, the effect of stocking density of salmon on the progression of AGD was also examined. The infective ability of different batches of amoebae isolated periodically from AGD-affected salmon varied in terms of quantifiable pathology. Salmon stocking density had a significant impact on survival after amoebae challenge, with morbidity beginning 23 days post challenge in tanks stocked at 5.0 kg m,3 and 29 days for those stocked at 1.7 kg m,3. For uniform initiation of AGD in multiple tanks, amoebae batches should be equally divided and added to tanks until the required concentration is reached and to maintain a standard biomass between replicate tanks and treatments. 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