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The aim of this case study was to explore health-education students’ personal and collaborative meaning making activities during an online science philosophy course in the higher-education context. Through applying the dialogical perspective for learning, the focus was on studying how different contextual resources were used in building understanding within the philosophy of science and what kind of understanding the students constructed and reflected through these resources. The study focused especially on exploring how the students’ life experiences and fellow students served as resources in their meaning making activities. The results showed that prior work and discipline-related knowledge and experiences provided the students with resources for understanding the philosophical texts by applying, conceptualizing, or critically evaluating the philosophical knowledge presented in the texts. In their discursive activities, the students used fellow students as resources in elaborating the theoretical conceptualizations further, or they were engaged in sharing their similar work or discipline-related experiences and conceptions. These different resources offered tools for understanding, conceptualizing, and critically evaluating both the philosophical themes studied and the practices of one’s own work and those of the scientific community.  相似文献   
3.
A novel approach to synthesize carbon nanofibers (CNFs) directly on the surface of metal μm-sized particles to evenly disperse the carbon nanomaterials in a composite material was proposed. As a metal matrix, 5–10 μm copper particles were utilized. As a carbon source, C2H2, CH4 and CO were examined. The best conditions were found to be in C2H2 (30 cm3/min) and H2 (260 cm3/min) atmosphere at the temperature of 750 °C. The composites based on copper and CNFs prepared by vacuum hot pressing showed the increase in hardness from 35 to 60 kg/mm2 almost retaining pure copper electrical properties.  相似文献   
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The effect of decontamination methods on fresh‐cut vegetable washing waters was evaluated. NEW, ClO2, organic acid‐based product FPW, and UV‐C were tested with and without an interfering carrot juice of 1% (IS), on Yersinia enterocolitica and Yersinia pseudotuberculosis, Escherichia coli, and yeast Candida lambica. The use of ClO2 (50 ppm active chlorine) resulted in >4 log reduction of Y. enterocolitica, Y. pseudotuberculosis, E. coli and >3 log reduction of C. lambica. The antibacterial effect of NEW was less effective in the presence of IS when compared with ClO2. The inactivation of C. lambica by FPW reached a maximum of 2.8 log cfu/mL (concentration 0.125%), but the antimicrobial effect was delayed by the IS. The effect of FPW on E. coli was significantly reduced by 1% IS. The inactivation of E. coli and C. lambica with UV‐C IS decreased the inactivation and lengthened its time. Filtration improved the effect of UV‐C inactivation.

Practical applications

When chemical decontamination methods were used in fresh‐cut vegetable processing, the presence of organic matter in process water increased the reaction times and the need for higher concentrations of the chemical decontamination and the time of physical decontamination. Yersinia required longer inactivation times than E. coli. When UV‐C is used for decontamination of process waters, waters should be filtered to enhance the disinfection efficacy.  相似文献   
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In most fruit and berry products the attractive red color is unstable and easily susceptible to degradation. The colors of strawberry and raspberry juices can be enhanced and stabilized by the addition of cinnamic acids. The aim of this study was to identify the novel anthocyanin products responsible for the improved juice color. The pyranoanthocyanins formed were detected using high-performance liquid chromatography, and the fractions from this were analyzed using a nano-ESI tandem MS technique. The pyranoanthocyanins identified were formed from reactions of the main anthocyanins of strawberry and raspberry juices with ferulic acid or sinapic acid. The new anthocyanin derivatives were the 4-vinylguaiacol and 4-vinylsyringol adducts of pelargonidin and cyanidin. This is the first time that pelargonidin 3-glucoside-based vinylphenol pyranoanthocyanins and pyranoanthocyanins with more complex sugar residues have been found. This is also the first time pyranoanthocyanins have been detected in strawberry and raspberry juices.  相似文献   
6.
Plant lignans are converted to mammalian forms, enterodiol and enterolactone, in the colon. Enhanced plasma or urinary enterolactone levels have been associated with lowered risk of cardiovascular diseases and breast cancer. Processed rye bran and its fractions were compared to ascertain the fermentation rates of fermentable carbohydrates and the bioconversion of lignans. Rye bran was extruded and treated with a food‐grade xylanase. Part of the xylanase‐treated rye bran was separated into a soluble rye bran extract and an insoluble residue, and a part of the xylanase‐treated rye bran was freeze‐dried without separation. All the samples were digested by pepsin and pancreatin and subsequently fermented with a human faecal inoculum in vitro. The consumption of carbohydrates, the productions of short‐chain fatty acids (SCFA), enterodiol and enterolactone were followed as a function of time. The soluble rye bran extract showed the fastest fermentation rate and the highest extent of fermentation determined as the consumption of neutral sugar residues (arabinose, xylose and glucose), the production of SCFA and the formation of enterodiol and enterolactone. Xylanase treatment enhanced the fermentation rate of extruded rye bran. An even a higher fermentation rate was observed for rye bran extract containing soluble carbohydrates. The amount of enterolactone precursors in rye seemed to be too low for enterolactone formation using an amount of substrate suitable for carbohydrate fermentation. However, xylanase treatment enhanced the availability of plant lignans from rye bran, as enterodiol formation was increased by the use of xylanase. Copyright © 2005 Society of Chemical Industry  相似文献   
7.
Microstructures of the RuSr(2)Gd(1.5)Ce(0.5)Cu(2)O(10-delta) (Ru-1222) and RuSr(2)GdCu(2)O(8) (Ru-1212) magneto-superconductors have been investigated by using selected-area electron diffraction, convergent-beam electron diffraction, dark-field electron microscopy and high-resolution electron microscopy at room temperature. Both Ru-1212 and Ru-1222 consist of nm-size domains stacked along the [Formula: see text] direction, where the domains are formed by two types of superstructures due to ordering of rotated RuO(6) octahedra about the c-axis. In Ru-1212, both primitive-and body-centered tetragonal superstructures (the possible space groups: P4/mbm and I4/mcm) are derived to form the corresponding nm-domains. It is of great interest that Ru-1212 consists of domains of two crystallographically different superstructures, while the similar domains observed in Ru-1222 have crystallographically identical superstructure with an orthorhombic symmetry (possible space group: Aeam), related by 90 degrees rotation around the c-axis (Yokosawa et al., 2003, submitted for publication).  相似文献   
8.
Here various approaches to understanding the complex relationship among the local atomic arrangements, the distribution of charge/holes and the superconductivity characteristics are discussed for a variety of multi-layered copper-oxide superconductors. Regarding the structural parameters, i.e. bond lengths and angles, no single parameter is revealed to control the superconductivity characteristics alone. As a matter of fact, superconductivity properties are found to be correlated with the whole delicately balanced fine-structure that is described by a set of multiple parameters: it is shown that T c and Hirr are enhanced in somewhat opposite ways. Expressing the delicately balanced fine-structure through the charge/hole distribution, it is concluded that the more homogeneously distributed the charge carriers are the more enhanced is the Hirr characteristics, while the opposite is likely to apply to the T c value.  相似文献   
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The Telset system has been under development since 1975. Similar to Prestel, the system's database, for example, has the same three-way division into News-Telset, Home Telset and Business Telset as the UK system. The software is developed to run under the control of the RSX-11 V3 executive; the latter being a versatile real-time events. At the same time, however, the executive allows the system to carry out software development and run less urgent programs in parallel with the real-time application.  相似文献   
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