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191.
Miller Matthew J.; Sendrowitz Kerrin; Connacher Christopher; Blanco Susana; de la Pe?a Cristina Mu?iz; Bernardi Shaina; Morere Lauren 《Canadian Metallurgical Quarterly》2009,56(4):495
In this study, the authors examined the degree to which social-cognitive career theory (SCCT; R. W. Lent, S. D. Brown, & G. Hackett, 1994) explained the development of social justice interest and commitment. Data from 274 college students and latent variable path modeling were used to test theoretically and empirically derived SCCT direct and indirect effects structural models. The direct effects model estimated the direct effect of social supports and barriers on social justice commitment and the indirect effects model estimated the effect of social supports and barriers indirectly through self-efficacy. Overall, the present findings supported the use of SCCT within the social justice domain, as social justice self-efficacy and outcome expectations were useful in explaining the development of college students’ social justice interest and commitment. The present findings supported the indirect effects model of social justice interest and commitment over the direct effects model. Finally, unique to prior tests of SCCT in vocational and academic domains, social supports and barriers exhibited an indirect effect on commitment through outcome expectations. Study limitations, future directions for research, and implications for facilitating college students’ social justice interest and commitment are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
192.
Infant formula developed by manufacturers requires a rigorous control of composition, particularly those elements added routinely in an attempt to mimic the mineral composition of human milk. A total of 97 different types of powdered infant formulae (preterm, adapted starter, adapted follow-up, toddler, specialised and soy-based formulae) commercially available in Spain were studied. It is noteworthy great differences in mineral (Ca, P, Mg) and trace element (Zn, Fe, Cu, Mn) contents found between analysed and listed in label information. The development of a fast, simple and direct slurry method for the determination of these essential micronutrients in infant formula by inductively coupled plasma optical emission spectrometry (ICP OES) and flame atomic absorption spectrometry (FAAS) was performed in order to help in quality control tasks. Infant formula samples were solubilised using different amounts of several different solvents. An addition of 250 μL of a solution 10% tetramethylammonium hydroxide and 25% ammonium hydroxide were required for the accurate quantification of Ca and P, Mg, Zn, Fe, Cu and Mn, respectively. The standard reference material 1549 non-fat milk powder was solubilised to compare the validity of assayed methodology following slurry nebulisation and traditional microwave-assisted acid digestion method. Good agreement of the analytical results by both ICP OES and FAAS, with the certified values was obtained. Method performance parameters (accuracy, precision and methodological detection limits) were determined for studied elements to check the quality and usefulness of the optimised slurry method. The analytical procedure was applied successfully to the analysis of a representative group of infant formulae. Levels of analysed elements were graphically represented, showing an acceptable comparability between slurry and acid-mineralisation method set by linear correlation coefficients and slopes close to the unit. The described simple and slurry method is appropriate, as an attractive alternative, for routine control analysis of added essential elements in infant formulae regardless of predominant protein type used in manufacture. 相似文献
193.
Wickerhamomyces anomalus killer strains are important for fighting pathogenic yeasts and for controlling harmful yeasts and bacteria in the food industry. Targeted disruption of key genes in β‐glucan synthesis of a sensitive Saccharomyces cerevisiae strain conferred resistance to the toxins of W. anomalus strains BS91, BCA15 and BCU24 isolated from olive brine. Competitive inhibition of the killing activities by laminarin and pustulan refer to β‐1,3‐ and β‐1,6‐glucans as the main primary toxin targets. The extracellular exoglucanase‐encoding genes WaEXG1 and WaEXG2 from the three strains were sequenced and were found to display noticeable similarities to those from known potent W. anomalus killer strains. Accession Nos for WaEXG1 genes for the strains in brackets are JQ734563 (BS91), JQ734564 (BCA15) and JQ734565 (BCU24); for WaEXG2 genes JQ734566 (BS91), JQ734567 (BCA15) and JQ734568 (BCU24), respectively. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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This paper deals with the study of volatile compounds released by recycled paper and board. The aim of the study was to demonstrate the feasibility of headspace procedure coupled to gas chromatography/mass spectrometry (GC/MS) applied to complex paper‐based samples together with a chemometric procedure as a powerful method for screening potential volatile contaminants released by the recycled and virgin paper samples. Using this procedure, the identification of virgin or recycled paper could be achieved based on the identification on specific markers of the recycled pulp. Fifteen different samples within virgin and recycled paper were studied. After equilibration, the vapour phase of the samples was analysed by automatic headspace coupled online to GC/MS. The analytical approach for volatile compounds, their identification and the selection of some compounds as markers for recycled pulp are shown and discussed. A discriminate analysis applied to the set of results obtained allows classification of the samples into four different groups according to the content of recycled pulp (0, 10–30 and > 80% of recycled pulp), the surface treatment of the paper (no surface treatment, clay coating and plastic coating), the grammage (from < 100 to > 300 g/m2) and the sample thickness (from < 300 to > 600 µm). The matrix effect on the volatilization of some compounds from the paper samples and the analytical behaviour are also discussed. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
196.
Sara Salucci Sabrina Burattini Michela Battistelli Valentina Baldassarri Maria Cristina Maltarello Elisabetta Falcieri 《International journal of molecular sciences》2013,14(1):532-546
Ultraviolet B (UVB) radiation acts as a strong apoptotic trigger in many cell types, in tumor and normal cells. Several studies have demonstrated that UVB-induced cell death occurs through the generation of reactive oxygen species. The consequent oxidative stress includes the impairment of cellular antioxidants, the induction of DNA damage and the occurrence of apoptosis. In this review, we investigated UVB apoptotic action in various cell models by using ultrastructural, molecular and cytofluorimetric techniques. Myeloid leukemia HL-60, T-lymphoblastoid Molt-4 and myelomonocytic U937 human cells, generally affected by apoptotic stimuli, were studied. Human chondrocytes and C2C12 skeletal muscle cells, known to be more resistant to damage, were also considered. All of them, when exposed to UVB radiation, revealed a number of characteristic apoptotic markers. Membrane blebbing, cytoplasm shrinkage and chromatin condensation were detected by means of electron microscopy. DNA cleavage, investigated by using agarose gel electrophoresis and TUNEL reaction, was observed in suspended cells. Differently, in chondrocytes and in skeletal muscle cells, oligonucleosomic DNA fragmentation did not appear, even if a certain TUNEL positivity was detected. These findings demonstrate that UVB radiation appears to be an ideal tool to study the apoptotic behavior. 相似文献
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199.
Joachim Mittendorf Prof. Dr. Stefan Weigand Dr. Cristina Alonso‐Alija Dr. Erwin Bischoff Dr. Achim Feurer Dr. Michael Gerisch Dr. Armin Kern Dr. Andreas Knorr Dr. Dieter Lang Dr. Klaus Muenter Dr. Martin Radtke Dr. Hartmut Schirok Dr. Karl‐Heinz Schlemmer Dr. Elke Stahl Dr. Alexander Straub Dr. Frank Wunder Dr. Johannes‐Peter Stasch Dr. 《ChemMedChem》2009,4(5):693-693
200.
Cristina Megías 《LWT》2009,42(1):228-926
The purification of a peptidic fraction with angiotensin converting enzyme (ACE) inhibitory activity from sunflower protein hydrolysates by affinity chromatography was recently described. We now describe that reverse-phase HPLC fractionation of this product yields several fractions with IC50 one order of magnitude higher than those previously purified by reverse-phase HPLC following gel filtration chromatography, showing that affinity chromatography is much more effective than gel filtration chromatography as a first step for purification of ACE inhibitory peptides. The amino acid composition of these fractions is presented, but attempts to determine their amino acid sequence failed, showing that these fractions contained more than one peptide. 相似文献