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Postulating that academic papers can positively impact the actual teaching practices of science teachers, this study analysed the process of understanding and utilising academic papers by science teachers to teach scientific creativity in their schools. The 45–hour graduate course of three science teachers was explored to identify the difficulties teachers encountered in trying to understand academic papers and to discover how to solve these difficulties. Second, which aspects should be considered when developing teaching materials for scientific creativity to be used in schools were analysed. A transformation model of an academic paper was proposed to understand this process, and the results were organised accordingly. According to this model, it was emphasized to translate academic papers from a general and abstract state to a local and concrete state. Therefore, the role of science educators as knowledge translators was discussed for more practical and effective use of academic papers in school. This study is expected to contribute to research-based teaching by linking academic research with teaching practice. Keywords: case study, research-based teaching, scientific creativity, teacher’s learning process, teaching plan

This research examined theory-based teaching processes of science teachers to understand the mechanism by which theory and practice were connected. Four science teachers desgined lesson plans by applying the empirical-abductive learning cycle (EALC) model and modified lesson plans through a collaborative interview with the researcher. Data were obtained from lesson plans and interviews. Using the constant comparison method with open coding, data were analyzed to find out obstacles or facilitators acted in the process of applying the EALC model to design lesson plans and reveal the path through which theory and practice were connected. As a result, it was found that perceptive prejudice about the role and necessity of the EALC model was the main obstacle. The collaboration process helped teachers understand the EALC model clearly and deeply. The development of this cognitive understanding changed their prejudice about the EALC model and led them to reflect their teaching practices with the eyes of theory. Through this process, a separated state between theory and practice was developed to a connected state. With the belief that it is a good starting point for coordination between theory and practice, further studies are proposed. Keywords: abductive thinking, lesson plan, learning cycle, hypothesis generation, theory-based teaching

Teachers’ and parents’ perceptions of scientific creativity are assumed to be an important environmental factor for scientific creativity, so this research surveyed their perceptions of the behavioral characteristics of scientific creativity and compared their perceptions to those of students. This is achieved with a list of behavioral characteristics of creative physicists during their growth period. For this survey, 48 science teachers, 112 parents, and 145 science gifted students participated. Out of the 30 items of the list, they selected 10 items that were considered important indicators to become creative scientists in the future, and they ranked them according to their importance. The results showed that the three groups all perceived ‘conducting experiments, asking questions, thinking logically to solve difficult problems, and sharing ideas’ as important for scientific creativity. For the items that were perceived to be less important, it was discussed why these items might be necessary for scientific creativity. Comparative result showed that parents gave more importance to learning-related aspects, teachers to thinking-related aspects, and students to activities such as making and experimenting. This research showed the behavioral characteristics that should be encouraged to improve students’ scientific creativity at school and at home. Keywords: behavioral characteristics, creativity perception, creative environment, scientific creativity

Isotope dilution mass spectrometry (ID-MS) based on liquid chromatography tandem mass spectrometry (LC/MS/MS) was developed for the accurate determination of sorbic acid in tea-drink. An isotope analogue of sorbic acid, 13 C 2 -sorbic acid, was obtained by custom synthesis. MS was operated in the negative mode with selected reaction monitoring (SRM) mode of [M-H]- → [M-CO 2 H]- channel at m/z 111 → 67 for sorbic acid and at m/z 113 → 68 for its isotope analogue. Chromatographic separation was accomplished with a C18 column and an isocratic mobile phase of 55% of 50 mM ammonium acetate (pH 4.5) and 45% of methanol. Homogeneous reference materials were prepared for validation of this method, including repeatability and reproducibility tests, by fortifying tea-drink with sorbic acid in our laboratory. Repeatability and reproducibility studies showed that the ID-LC/MS method is a reliable and reproducible method which provides less than 3.8% of relative standard deviation (RSD) for the analysis of sorbic acid.

ATP pyrophosphatases (ATP PPases) are widely distributed in archaea and eukaryotes. They share an HUP domain at the N-terminus with a conserved PP-­motif that interacts with the phosphates of ATP. The PF0828 protein from Pyrococcus furiosus is a member of the ATP PPase superfamily and it also has a 100-residue C-terminal extension that contains a strictly conserved EGG(E/D)xE(T/S) motif, which has been named the EGT-motif. Here, crystal structures of PF0828 alone and in complex with ATP or AMP are reported. The HUP domain contains a central five-stranded β-sheet that is surrounded by four helices, as in other related structures. The C-terminal extension forms a separate domain, named the EGT domain, which makes tight interactions with the HUP domain, bringing the EGT-motif near to the PP-motif and defining the putative active site of PF0828. Both motifs interact with the phosphate groups of ATP. A loop in the HUP domain undergoes a large conformational change to recognize the adenine base of ATP. In solution and in the crystal PF0828 is a dimer formed by the side-by-side arrangement of the HUP domains of the two monomers. The putative active site is located far from the dimer interface.

This paper investigates the role of regional food festivals for destination branding and explores the characteristics of regional food festivals that contribute to building a destination brand. It was found that regional food festivals can play a decisive role for destination branding. Activities using local food and activities promoting the regions' attractions were suggested to be offered by food festivals for enhancing the impact of festivals for destination branding and improving the positive image of the destination and local food. The findings of the study offer insights to regional food festival organizers and destination marketers for success in destination marketing

A certified reference material (CRM), KRISS CRM 108-10-003, has been developed for analysis of acrylamide in potato chips, as a representative of carbohydrate-rich food cooked in high-temperature oil. The material was prepared by grinding commercially available potato chips to a paste which was then homogenized, bottled in 15-g units, and stored at -70 °C. Certification, homogeneity and stability testing, were carried out by liquid chromatography-isotope-dilution mass spectrometry (ID-LC-MS). A single ID-LC-MS measurement was performed for each of 10 selected units for certification and homogeneity assessment. The mean measurement result for the 10 bottles, 0.455 ± 0.012 mg kg(-1), was assigned as the certified value of the CRM. The between-bottle homogeneity was 0.8% of the certified value. The within-bottle homogeneity, tested by measuring three replicate sub-samples from each of three randomly selected bottles, was similar to the between-bottle homogeneity. The stability of the CRM under storage conditions (-70 °C) was tested for 21 months and no change in the acrylamide content was observed within the measurement uncertainty. Stability of the CRM at -20 °C (storage at user's site) and room temperature (for regular use and transportation) was also tested. Also presented is the newly designed procedure for evaluating the uncertainty of the certified value for the characterization scheme used in this study.

extraction steps. For the chromatographic separation, a C18 column with isocratic mobile phase of 50:50 (v/v) ammonium acetate buffer at pH 4.5 and methanol mixture was used. MS was operated with electrospray ionization in the negative mode. Benzoic acid and its isotope analogue were detected by selectively monitoring the collisionally-induced dissociation channels of [M-H] � → [M-CO2H] � at m/z 121 → 77 and m/z 127 → 83, respectively. Repeatability and reproducibility studies showed that the ID-LC/MS/MS method is a reliable and reproducible method which can provide less than 0.3% of relative standard deviation (RSTD) of method precision for analysis of benzoic acid.

The purpose of this study was to investigate the improvement of allergic dermatitis in chemical allergen-induced mice by Lactobacillus sakei probio 65. L. sakei probio-65 was isolated from kimchi, a traditional Korean fermented food. This strain was resistant to gastric acidity, bile, and several antibiotics and possessed antimicrobial activity against several pathogenic microorganisms. To investigate whether the probiotic activity of L. sakei probio 65 was effective for treating allergic dermatitis, the organism was supplied to mice triggered by allergen (1-chloro-2,4-dinitrobenzene). Mice that received L. sakei probio 65 showed a more rapid recovery compared to control mice, as assessed by visual evaluation of the severity of allergic dermatitis and levels of immunoglobulin (Ig) E and interleukin (IL)-4. L. sakei probio 65 exhibited good probiotic properties in vitro and in mice and was effective in reducing allergen-induced skin inflammation through the regulation of both elevated IgE and IL-4 in sensitized mice.

TenA (transcriptional enhancer A) has been proposed to function as a transcriptional regulator based on observed changes in gene-expression patterns when overexpressed in Bacillus subtilis. However, studies of the distribution of proteins involved in thiamine biosynthesis in different fully sequenced genomes have suggested that TenA may be an enzyme involved in thiamine biosynthesis, with a function related to that of the ThiC protein. The crystal structure of PF1337, the TenA homolog from Pyrococcus furiosus, is presented here. The protomer comprises a bundle of alpha-helices with a similar tertiary structure and topology to that of human heme oxygenase-1, even though there is no significant sequence homology. A solvent-sequestered cavity lined by phylogenetically conserved residues is found at the core of this bundle in PF1337 and this cavity is observed to contain electron density for 4-amino-5-hydroxymethyl-2-methylpyrimidine phosphate, the product of the ThiC enzyme. In contrast, the modestly acidic surface of PF1337 shows minimal levels of sequence conservation and a dearth of the basic residues that are typically involved in DNA binding in transcription factors. Without significant conservation of its surface properties, TenA is unlikely to mediate functionally important protein-protein or protein-DNA interactions. Therefore, the crystal structure of PF1337 supports the hypothesis that TenA homologs have an indirect effect in altering gene-expression patterns and function instead as enzymes involved in thiamine metabolism. journal: Acta Crystallographica Section D: Biological Crystallography content_type: research papers peer_reviewed: Yes review_process: Single blind received: 22 November 2004 accepted: 15 February 2005 published_online: 20 April 2005 supplementary_materials: This article has supplementary materials copyright: © 2005 International Union of Crystallography ispartof: Acta Crystallographica D vol:61 issue:Pt 5 pages:589-98 ispartof: location:United States status: published

This paper investigates the visitor benefits gained from attending a multicultural festival in South Korea. It aims to improve the understanding of such festivals, and explore the contribution of multicultural festivals to building multicultural societies. Four key factors were identified in terms of benefits gained: transformational, cognitive, social, and affective benefits. Differences were found between the visitor benefits of the dominant population and those of migrants. The findings may assist stakeholders to better understand how multicultural festivals contribute to social harmony and social integration, particularly in countries experiencing significant shifts in ethnic composition. Refereed/Peer-reviewed

In this paper, we propose two operating scenarios of employing cognitive radio to downlink of relay networks. The first scenario uses ISM band while the second scenario exploits opportunity of channel use at UHF spectrum. The capacity gain over conventional relay is investigated in terms of the normalized system capacity. We first statistically model the spectrum usage pattern in those bands and derive the achievable data rate and outage probability in order to analyze performance gain in the view of practical system establishment. Then, we define system capacity by normalizing the effect of bandwidth so that a fair comparison of performance is accomplished. Through our analysis and simulations, it is shown that the proposed scenarios are able to achieve significant gains over a conventional cellular relay system in terms of the normalized system capacity. As a result, relay combined with cognitive radio can be considered as a viable solution to get higher downlink capacity.

Hyperhomocysteinemia is associated with an increase in the incidence of vascular diseases, including retinal vascular diseases. We examined the effects of high plasma levels of homocysteine on retinal glial cells and vascular endothelial growth factor (VEGF) expression. Male Sprague-Dawley rats were fed either a 3.0 g/kg homocystine diet or a control diet for 2 week. The homocystine-diet group had higher plasma levels of homocysteine and thiobarbituric acid reactive substances (TBARSs) and lower plasma levels of folate, retinol, alpha-tocopherol, and retinal expression of CuZn superoxide dismutase (SOD) than the controls. The rats fed the homocystine-diet showed an increase in vimentin, glial fibrillary acidic protein (GFAP), and VEGF immunoreactivity in the retina as compared to the controls. The increase in vimentin immunoreactivity in the hyperhomocysteinemic rats was correlated with changes in GFAP immunoreactivity in astrocytes within the ganglion cell layer. We found for the first time that short-term hyperhomocysteinemia-induced oxidative stress activates retinal glial cells and increases VEGF expression in the retina.

Structural genomics efforts have produced structural information, either directly or by modeling, for thousands of proteins over the past few years. While many of these proteins have known functions, a large percentage of them have not been characterized at the functional level. The structural information has provided valuable functional insights on some of these proteins, through careful structural analyses, serendipity, and structure-guided functional screening. Some of the success stories based on structures solved at the Northeast Structural Genomics Consortium (NESG) are reported here. These include a novel methyl salicylate esterase with important role in plant innate immunity, a novel RNA methyltransferase (H. influenzae yggJ (HI0303)), a novel spermidine/spermine N-acetyltransferase (B. subtilis PaiA), a novel methyltransferase or AdoMet binding protein (A. fulgidus AF_0241), an ATP:cob(I)alamin adenosyltransferase (B. subtilis YvqK), a novel carboxysome pore (E. coli EutN), a proline racemase homolog with a disrupted active site (B. melitensis BME11586), an FMN-dependent enzyme (S. pneumoniae SP_1951), and a 12-stranded beta-barrel with a novel fold (V. parahaemolyticus VPA1032).

To evaluate the effects of dietary folic acid supplementation on the cerebral vascular damage induced by hyperhomocysteinemia, rats were fed a diet containing 3.0 g/kg homocystine for 2 wk and then either 3.0 g/kg homocystine or 3.0 g/kg homocystine plus 0.008 g/kg folic acid for 8 wk. Control rats consumed the AIN-93 Maintenance diet throughout the experiment. The cerebral expression of glucose transporter-1 was measured by Western blot analysis and cerebrovascular structural alterations were evaluated by electron microscopy. The homocystine diet significantly increased the plasma levels of homocysteine and TBARS and decreased the cerebral expression of glucose transporter-1 (GLUT-1) with a concomitant increase in the percentage of damaged cerebral vessels. The inclusion of dietary folic acid for 8 wk caused plasma homocysteine levels to be the same as in control rats and it significantly upregulated the cerebral expression of GLUT-1 that was significantly reduced by hyperhomocysteinemia. Folic acid supplementation also significantly decreased the incidence of damaged vessels due to hyperhomocysteinemia. These results and the electron microscopy findings suggested that folic acid supplementation might reduce the detrimental effects on the endothelium caused by experimentally induced hyperhomocysteinemia.

Escherichia coli YiaK catalyzes the reduction of 2,3-diketo-l-gulonate in the presence of NADH. It belongs to a large family of oxidoreductases that is conserved in archaea, bacteria, and eukaryotes but shows no sequence homology to other proteins. We report here the crystal structures at up to 2.0-A resolution of YiaK alone and in complex with NAD-tartrate. YiaK has a new polypeptide backbone fold and a novel mode of recognizing the NAD cofactor. In addition, NAD is bound in an unusual conformation, at the interface of a dimer of the enzyme. The crystallographic analysis unexpectedly revealed the binding of tartrate in the active site. Enzyme kinetics studies confirm that tartrate and the related d-malate are inhibitors of YiaK. In contrast to most other enzymes where substrate binding produces a more closed conformation, the binding of NAD-tartrate to YiaK produces a more open active site. The free enzyme conformation is incompatible with NAD binding. His44 is likely the catalytic residue of the enzyme.

We present here the 2.3-A crystal structure of the Escherichia coli YdiB protein, an orthologue of shikimate 5-dehydrogenase. This enzyme catalyzes the reduction of 3-dehydroshikimate to shikimate as part of the shikimate pathway, which is absent in mammals but required for the de novo synthesis of aromatic amino acids, quinones, and folate in many other organisms. In this context, the shikimate pathway has been promoted as a target for the development of antimicrobial agents. The crystal structure of YdiB shows that the protomer contains two alpha/beta domains connected by two alpha-helices, with the N-terminal domain being novel and the C-terminal domain being a Rossmann fold. The NAD+ cofactor, which co-purified with the enzyme, is bound to the Rossmann domain in an elongated fashion with the nicotinamide ring in the pro-R conformation. Its binding site contains several unusual features, including a cysteine residue in close apposition to the nicotinamide ring and a clamp over the ribose of the adenosine moiety formed by phenylalanine and lysine residues. The structure explains the specificity for NAD versus NADP in different members of the shikimate dehydrogenase family on the basis of variations in the amino acid identity of several other residues in the vicinity of this ribose group. A cavity lined by residues that are 100% conserved among all shikimate dehydrogenases is found between the two domains of YdiB, in close proximity to the hydride acceptor site on the nicotinamide ring. Shikimate was modeled into this site in a geometry such that all of its heteroatoms form high quality hydrogen bonds with these invariant residues. Their strong conservation in all orthologues supports the possibility of developing broad spectrum inhibitors of this enzyme. The nature and disposition of the active site residues suggest a novel reaction mechanism in which an aspartate acts as the general acid/base catalyst during the hydride transfer reaction.