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Selected AbstractsHow Do We Know?: Students Examine Issues of Credibility With a Complicated Multimodal Web-Based TextCURRICULUM INQUIRY, Issue 2 2009Mark Baildon ABSTRACT As reading continues to become governed by a spatial "logic of the image" rather than strictly a temporal or linear logic of written language (Kress, 2003), and readers increasingly engage with a range of Internet-based texts, a host of challenges ensue for educators and students alike. One of the most vexing of these challenges deals with discernments of credibility. Determining the credibility of multimodal texts, especially on/within the Internet with its "vast network of relations of credibility" (Burbules & Callister, 2000), is particularly challenging because these texts mix images, music, graphic arts, video, and print to make sophisticated claims supported by various forms or types of evidence. This article examines how a group of ninth-grade students grappled with issues of credibility after viewing the controversial Internet video, Loose Change, a well-documented and comprehensive multimedia account that argues the "real story" of September 11 was covered up by the U.S. government. Findings from the study highlight the range of knowledge and literacy practices students mobilized to "read" the video and the challenges they experienced reading and evaluating the video as a multimodal text. Implications of this work point to the need to consider epistemological issues and further develop tools that can support teachers and students in critically assessing multimodal texts. [source] Anthocyanin profile of Spanish Vitis vinifera L. red grape varieties in danger of extinctionAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2007S. GÓMEZ-ALONSO Abstract This paper reports on a study of the anthocyanin fraction in berry skins of ten minority red and pink grapevine varieties from Castilla-La Mancha (Spain) and two traditional varieties from this growing region, Tempranillo and Garnacha Tinta, as references. These varieties were correctly identified beforehand by analysing six microsatellite regions recommended by the GENRES 081 project; five varieties were identified with genotypes identical to those described previously, and five new genotypes not described for any variety according to the literature consulted. Grape skin extracts of each variety were analysed by HPLC-UV-Vis, and four perfectly differentiated anthocyanin profiles were obtained. In six out of ten varieties (Churriago, Unknown 1, Unknown 2, Ariño, Brujidera and Moravia Agria) the major anthocyanin was malvidin-3-glucoside (39%). Tinto Velasco contained more than 29% delphinidin-3-glucoside, Gordera Roja and Teta de Vaca Tinta more than 40% peonidin-3-glucoside, and Rojal more than 29% cyanidin-3-glucoside. Results of this work point out the existence of unusual anthocyanic profiles in several of these indigenous varieties, and highlight the necessity of studying the effects of variety on other flavonoids and their impact on wine colour. [source] Sphingosine kinase 1 inhibition sensitizes hormone-resistant prostate cancer to docetaxelINTERNATIONAL JOURNAL OF CANCER, Issue 11 2009Lysann Sauer Abstract It has recently been shown that docetaxel chemotherapy is effective in prolonging life in patients with prostate cancer (PCa). We have investigated potential ways of increasing the effectiveness of chemotherapy in this disease. We have previously reported that sphingosine kinase 1 (SphK1) inhibition is a key step in docetaxel-induced apoptosis in the PC-3 PCa cell line and that pharmacologicalSphK1 inhibition is chemosensitizing in the docetaxel-resistant PCa LNCaP cell line. In this study we have addressed the mechanism of docetaxel-induced apoptosis of PC-3 cells and identified SphK1-dependent and -independent components. We have shown that SphK1 inhibition by docetaxel is a two-step process involving an initial loss of enzyme activity followed by a decrease in SphK1 gene expression. Using hormoneresistant PC-3 and DU145 PCa cells we have demonstrated that both pharmacological and siRNA-mediated SphK1 inhibition leads to a four-fold decrease in the docetaxel IC50 dose. This work points out to potential ways of increasing the effectiveness of chemotherapy for PCa by SphK1 inhibition. © 2009 UICC [source] 5, flanking region of var genes nucleate histone modification patterns linked to phenotypic inheritance of virulence traits in malaria parasitesMOLECULAR MICROBIOLOGY, Issue 6 2007Jose Juan Lopez-Rubio Summary In the human malaria parasite Plasmodium falciparum antigenic variation facilitates long-term chronic infection of the host. This is achieved by sequential expression of a single member of the 60-member var family. Here we show that the 5, flanking region nucleates epigenetic events strongly linked to the maintenance of mono-allelic var gene expression pattern during parasite proliferation. Tri- and dimethylation of histone H3 lysine 4 peak in the 5, upstream region of transcribed var and during the poised state (non-transcribed phase of var genes during the 48 h asexual life cycle), ,bookmarking' this member for re-activation at the onset of the next cycle. Histone H3 lysine 9 trimethylation acts as an antagonist to lysine 4 methylation to establish stably silent var gene states along the 5, flanking and coding region. Furthermore, we show that competition exists between H3K9 methylation and H3K9 acetylation in the 5, flanking region and that these marks contribute epigenetically to repressing or activating var gene expression. Our work points to a pivotal role of the histone methyl mark writing and reading machinery in the phenotypic inheritance of virulence traits in the malaria parasite. [source] On the discontinuity of the costates for optimal control problems with Coulomb frictionOPTIMAL CONTROL APPLICATIONS AND METHODS, Issue 4 2001Brian J. Driessen Abstract This work points out that the costates are actually discontinuous functions of time for optimal control problems with Coulomb friction. In particular these discontinuities occur at the time points where the velocity of the system changes sign. To our knowledge, this has not been noted before. This phenomenon is demonstrated on a minimum-time problem with Coulomb friction and the consistency of discontinuous costates and switching functions with respect to the input switches is shown. Copyright © 2001 John Wiley & Sons, Ltd. [source] Phosphatase inhibitors with anti-angiogenic effect in vitroAPMIS, Issue 1 2010LENE SYLVEST Sylvest L, Bendiksen CD, Houen G. Phosphatase inhibitors with anti-angiogenic effect in vitro. APMIS 2010; 118: 49,59. Levamisole has previously been identified as an inhibitor of angiogenesis in vitro and in vivo, but the mechanism behind the anti-angiogenic behavior has not yet been established. However, one known effect of levamisole is the inhibition of alkaline phosphatase, and this fact encouraged us to test other phosphatase inhibitors for their anti-angiogenic effects by using the same method as used to identify levamisole: an ELISA-based co-culture angiogenesis assay giving quantitative and qualitative results. Historically, intracellular phosphatases have been associated with the downregulation of signaling pathways, and kinases with their upregulation, but lately, the phospatases have also been coupled to positive signaling, which is why inhibition of phosphatases has become associated with anti-tumorigenic and anti-angiogenic effects. The results obtained in this work reveal several agents with anti-angiogenic potential and give a strong indication that phosphatase inhibition is linked to anti-angiogenic activity. An apparent disruption of endothelial tube formation was seen for seven of eight phosphatase inhibitors tested in the angiogenesis assay. By looking at the morphological results, it was seen that most of the inhibitors impaired proliferation and elongation of the endothelial cells, which still had a differentiated appearance. One inhibitor, PTP inhibitor IV, seemed to impair endothelial cell differentiation and induced the same morphology as when cells were treated with levamisole, although at a 200 times lower concentration than that of levamisole. Hence, our work points out compounds with a potential that may be of use in the search for new medical products for the treatment of malignant tumors, or other conditions where angiogenesis plays a central role. [source] Effect of ellagitannins, ellagic acid and volatile compounds from oak wood on the (+)-catechin, procyanidin B1 and malvidin-3-glucoside content of model winesAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2008A.M. JORDÃO Abstract Background and Aims:, During ageing in oak barrels, wine undergoes changes because of the release of polyphenols and other molecules from wood. The aim of this study was to evaluate the influence of some oak wood-derived volatile compounds, ellagic acid and oak wood extracts on the levels of (+)-catechin, procyanidin B1 and malvidin-3-glucoside. Methods and Results:, Phenolics and the oak wood derived volatile compounds studied were quantified by HPLC and by GC, respectively. Additionally, the new compounds formed in the solutions were characterised by their spectral properties. Ellagic acid and/or oak wood extracts slowed the decline in the levels of (+)-catechin and procyanidin B1. In contrast, the decrease in malvidin-3-glucoside was more pronounced in the presence of ellagic acid and oak wood chip extracts. Furfural slowed (+)-catechin degradation, while breakdown of malvidin-3-glucoside was slightly more pronounced in the presence of guaiacol, furfural, vanillin and eugenol. (+)-Catechin, procyanidin B1 and malvidin-3-glucoside did not significantly affect the rate of the degradation of ellagitannins during the storage time studied. Finally, new HPLC peaks were detected in the solutions containing (+)-catechin and ellagic acid, as well as with malvidin-3-glucoside with ellagic acid and oak wood extract. Conclusions:, Malvidin 3-glucoside and (+)-catechin and procyanidin B1 presented distinct behaviours during time in the presence of volatile and non-volatile compounds from oak wood. Significance of the Study:, This work points out the importance of oak wood components in the degradation of anthocyanins and tannins, as well as the reactions that occur during the ageing of red wine. [source] | ||||||||||