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Integrating Internet resources into the learning of English as a foreign language in a Taiwanese high school : a case study.
This research study explores use of Internet resources for learning English as a foreign language (EFL) in Taiwanese high school EFL education. The overall objectives of this research are to examine qualitatively 40 high school students\u27 performance, attitudes, and learning strategies using an experimental Internet-integrated learning mode; to consider its potential impact on current EFL education in Taiwan; and to gain insight into the feasibility of integrating the Internet into Taiwanese high school EFL standard curriculum. Subjects were engaged in thematic, purposeful, collaborative Internet-integrated learning activities where English is used for data searching, group discussion, and individual presentation, as well as for acquiring knowledge of other subject matter. E-mail messages, mailing lists, interviews, questionnaires and subjects\u27 writing samples were collected and analyzed. Students\u27 performances were recorded through fieldnotes, audiotaping, and videotaping. Results indicate that the Internet-integrated learning environment sufficiently scaffolded subjects in information processing and knowledge construction of the target language via exploration, discovery, and meaning-negotiated interactions. Results are discussed in terms of meeting the demands of information and human resources required for effective EFL learning and reshaping the role of instructor as guide and co-learner. Also discussed is how the Internet-integrated mode facilitates interdisciplinary, collaborative and learner-centered EFL learning and incorporates students\u27 and teachers\u27 interests and expertise. Finally, recommendations are offered for future research studies, including possibly developing a compatible assessment system and establishing an EFL instruction web station to convince and support teachers interested in conducting authentic, cross-cultural, and learner-centered EFL instruction with the aid of rich and dynamic multimedia resources on the Internet
Development of Passive Quarter Car Suspension Prototype
In this paper, a construction of a prototype to represent passive vehicle suspension system for quarter car model is considered. The prototype is represented by two degree-of freedom quarter-car model which are conventionally used by researchers. This laboratory equipment is developed in order to familiarize students with 2 DoF passive suspension system model. It consists of two masses, two springs and a damper. This equipment is easily dismantled and could be assembled with different spring and damper constants which contribute to different characteristics of the suspension system. A number of experiments have been carried out using the experiment setup in order to identify the suspension system characteristics i.e. experiments with different vehicle body mass, different period for one pulse and different pulse width of input pressure of the road excitation have been conducted. The experiment results are evaluated based on the vehicle body displacement and tire displacement of the prototype. Experiment results show that the pulse width of the input pressure or road profile is directly affected the characteristic of this passive suspension system. Lastly, simulations were done in order to compare the simulation and experiment results. Next step is to implement active control to this system via active actuators
Mutagenesis of the fusion peptide-like domain of hepatitis C virus E1 glycoprotein: involvement in cell fusion and virus entry
<p>Abstract</p> <p>Background</p> <p>Envelope (E) glycoprotein E2 of the hepatitis C virus (HCV) mediates binding of the virus to target cell receptors. Nevertheless, the precise role of E1 in viral entry remains elusive.</p> <p>Methods</p> <p>To understand the involvement of the fusion peptide-like domain positioned at residues 264 to 290 within envelope glycoprotein E1 in HCV infection, mutants with Ala and Asn substitutions for residues conserved between HCV and E proteins of flaviviruses or the fusion proteins of paramyxoviruses were constructed by site-directed mutagenesis and their effects on membrane fusion and viral infectivity were examined.</p> <p>Results</p> <p>None of these mutations affected the synthesis or cell surface expression of envelope proteins, nor did they alter the formation of a non-covalent E1-E2 heterodimer or E2 binding to the large extracellular loop of CD81. The Cys residues located at positions 272 and 281 were unlikely involved in intra- or intermolecular disulfide bond formation. With the exception of the G267A mutant, which showed increased cell fusion, other mutants displayed reduced or marginally inhibited cell fusion capacities compared to the wild-type (WT) E1E2. The G267A mutant was also an exception in human immunodeficiency virus type 1 (HIV-1)/HCV E1E2 pseudotyping analyses, in that it showed higher one-cycle infectivity; all other mutants exhibited greatly or partially reduced viral entry versus the WT pseudotype. All but the G278A and D279N mutants showed a WT-like profile of E1E2 incorporation into HIV-1 particles. Since C272A, C281A, G282A, and G288A pseudotypes bound to Huh7 cells as effectively as did the WT pseudotype, the reduced infectivity of these pseudotypes was due to their ability to inhibit cell fusion.</p> <p>Conclusion</p> <p>Our results indicate that specific residues, but not the structure, of this fusion peptide-like domain are required for mediating cell fusion and viral entry.</p
Cardiotoxicity Associated with Trastuzumab Therapy in Taiwan: A Single Medical Center's 5-Year Experience
AbstractIntroductionTrastuzumab, a recombinant humanized monoclonal antibody, targets the external domain of HER2 to improve the efficacy of HER2-positive breast cancer treatment and inhibit carcinoma cellular proliferation. The purpose of this study was to identify early changes in cardiac function and dimensional changes in heart size in patients treated with trastuzumab.Materials and MethodsSeventy three female patients with Her2/neu overexpression (IHC 3+/Fish +) in breast cancer underwent echocardiography before and after trastuzumab therapy.ResultsCardiac complications developed in 14 patients (19.2%), including asymptomatic left ventricle systolic dysfunction (n = 12), symptomatic heart failure (n = 2), new asymptomatic left bundle branch block (n = 1), new negative T waves on electrocardiogram (n = 2), pericardial effusion (n = 1), and death (n = 1). No significant deterioration in diastolic function was noted, and right heart diameters and function did not change significantly. Most patients remained in an asymptomatic stage of cardiac disease. A significant decrease in left ventricular ejection fraction (LVEF) was observed in 14 patients (19.2%), and new mitral regurgitation (≥ grade 1) was noted after 3 months of trastuzumab therapy in 7 patients (9.6%).ConclusionsTrastuzumab led to measurable decreases in LVEF (but only 2.7% was symptomatic heart failure) and new mitral regurgitation. Therefore, regular follow-up with echocardiography is essential for early detection and prevention of trastuzumab-induced cardiomyopathy
Use of Rubber Dams During Root Canal Treatment in Taiwan
Background/PurposeIsolation of teeth with rubber dams is an important procedure for infection control in dentistry, especially in endodontic treatment. This study surveyed the prevalence of rubber dam usage in nonsurgical root canal treatment (RCT) by dentists under the National Health Insurance system in Taiwan.MethodsA total of 1,332 completed RCT cases were randomly selected from a large database from the Bureau of National Health Insurance in Taiwan in 2004. The radiographs and dental charts of the selected cases were evaluated for the prevalence of rubber dam usage in RCT. The frequencies of rubber dam usage for RCT by dentists were compared between hospitals and private dental clinics and among six different regions in Taiwan.ResultsThe overall prevalence of rubber dam usage for RCT by dentists under the National Health Insurance system in Taiwan was 16.5%. The frequency of rubber dam usage for RCT by dentists in hospitals (32.8%) was significantly higher than that (10.3%) in private dental clinics (p < 0.0001). However, there was no significant difference in the frequency of rubber dam usage for RCT by dentists among six different geographic regions in Taiwan.ConclusionThe prevalence of rubber dam usage for RCT by dentists in Taiwan is relatively low. Because rubber dam isolation of an endodontically-treated tooth can provide better infection control, increase patient protection, and improve treatment efficiency, there is an urgent need to advise dentists in Taiwan to use rubber dams for every RCT case
Aqueous Extract from Hibiscus sabdariffa Linnaeus Ameliorate Diabetic Nephropathy via Regulating Oxidative Status and Akt/Bad/14-3-3γ in an Experimental Animal Model
Several studies point out that oxidative stress maybe a major culprit in diabetic nephropathy. Aqueous extract of Hibiscus sabdariffa L. (HSE) has been demonstrated as having beneficial effects on anti-oxidation and lipid-lowering in experimental studies. This study aimed at investigating the effects of Hibiscus sabdariffa L. on diabetic nephropathy in streptozotocin induced type 1 diabetic rats. Our results show that HSE is capable of reducing lipid peroxidation, increasing catalase and glutathione activities significantly in diabetic kidney, and decreasing the plasma levels of triglyceride, low-density lipoprotein (LDL) and increasing high-density lipoprotein (HDL) value. In histological examination, HSE improves hyperglycemia-caused osmotic diuresis in renal proximal convoluted tubules (defined as hydropic change) in diabetic rats. The study also reveals that up-regulation of Akt/Bad/14-3-3γ and NF-κB-mediated transcription might be involved. In conclusion, our results show that HSE possesses the potential effects to ameliorate diabetic nephropathy via improving oxidative status and regulating Akt/Bad/14-3-3γ signaling
Resveratrol Downregulates Interleukin-6-Stimulated Sonic Hedgehog Signaling in Human Acute Myeloid Leukemia
IL-6 and sonic hedgehog (Shh) signaling molecules are considered to maintain the growth of cancer stem cells (CSCs). Resveratrol, an important integrant in traditional Chinese medicine, possesses certain antitumor effects. However, the mechanisms on regulating acute myeloid leukemia (AML) are unclear. This study first used human subjects to demonstrate that the plasma levels of IL-6 and IL-1β in AML patients were higher and lower, respectively, than healthy donors. The expression of Shh preproproteins, and C- and N-terminal Shh peptides increased in bone marrow and peripheral blood mononuclear cells isolated from AML patients, and the plasma N-Shh secretion was greater. To further clarify the effect of IL-6 and resveratrol in Shh signaling, human AML HL-60 cells were tested. IL-6 upregulated Shh and Gli-1 expression and was accompanied by an increase of cell viability. Resveratrol significantly decreased CSC-related Shh expression, Gli-1 nuclear translocation, and cell viability in IL-6-treated HL-60 cells and had synergistic effect with Shh inhibitor cyclopamine on inhibiting cell growth. Conclusions. IL-6 stimulated the growth of AML cells through Shh signaling, and this effect might be blocked by resveratrol. Further investigations of Shh as a prognostic marker and resveratrol as a therapeutic drug target to CSCs in AML are surely warranted
O-GlcNAc modifications regulate cell survival and epiboly during zebrafish development
<p>Abstract</p> <p>Background</p> <p>The post-translational addition of the monosaccharide O-linked β-<it>N</it>-acetylglucosamine (O-GlcNAc) regulates the activity of a wide variety of nuclear and cytoplasmic proteins. The enzymes O-GlcNAc Transferase (Ogt) and O-GlcNAcase (Oga) catalyze, respectively, the attachment and removal of O-GlcNAc to target proteins. In adult mice, Ogt and Oga attenuate the response to insulin by modifying several components of the signal transduction pathway. Complete loss of <it>ogt </it>function, however, is lethal to mouse embryonic stem cells, suggesting that the enzyme has additional, unstudied roles in development. We have utilized zebrafish as a model to determine role of O-GlcNAc modifications in development. Zebrafish has two <it>ogt </it>genes, encoding six different enzymatic isoforms that are expressed maternally and zygotically.</p> <p>Results</p> <p>We manipulated O-GlcNAc levels in zebrafish embryos by overexpressing zebrafish <it>ogt</it>, human <it>oga </it>or by injecting morpholinos against <it>ogt </it>transcripts. Each of these treatments results in embryos with shortened body axes and reduced brains at 24 hpf. The embryos had 23% fewer cells than controls, and displayed increased rates of cell death as early as the mid-gastrula stages. An extensive marker analysis indicates that derivatives of three germ layers are reduced to variable extents, and the embryos are severely disorganized after gastrulation. Overexpression of Ogt and Oga delayed epiboly and caused a severe disorganization of the microtubule and actin based cytoskeleton in the extra-embryonic yolk syncytial layer (YSL). The cytoskeletal defects resemble those previously reported for embryos lacking function of the Pou5f1/Oct4 transcription factor <it>spiel ohne grenzen</it>. Consistent with this, Pou5f1/Oct4 is modified by O-GlcNAc in human embryonic stem cells.</p> <p>Conclusion</p> <p>We conclude that O-GlcNAc modifications control the activity of proteins that regulate apoptosis and epiboly movements, but do not seem to regulate germ layer specification. O-GlcNAc modifies the transcription factor Spiel ohne grenzen/Pou5f1 and may regulate its activity.</p
Antidiabetic effect and mode of action of cytopiloyne
Cytopiloyne was identified as a novel polyacetylenic compound. However, its antidiabetic properties are poorly understood. The aim of the present study was to investigate the anti-diabetic effect and mode of action of cytopiloyne on type 2 diabetes (T2D). We first evaluated the therapeutic effect of cytopiloyne on T2D in db/db mice. We found that one dose of cytopiloyne reduced postprandial glucose levels while increasing blood insulin levels. Accordingly, long-term treatment with cytopiloyne reduced postprandial blood glucose levels, increased blood insulin, improved glucose tolerance, suppressed the level of glycosylated hemoglobin A1c (HbA1c), and protected pancreatic islets in db/db mice. Next, we studied the anti-diabetic mechanism of action of cytopiloyne. We showed that cytopiloyne failed to decrease blood glucose in streptozocin- (STZ-)treated mice whose β cells were already destroyed. Additionally, cytopiloyne dose dependently increased insulin secretion and expression in β cells. The increase of insulin secretion/expression of cytopiloyne was regulated by protein kinase C α (PKC α ) and its activators, calcium, and diacylglycerol (DAG). Overall, our data suggest that cytopiloyne treats T2D via regulation of insulin production involving the calcium/DAG/PKC α cascade in β cells. These data thus identify the molecular mechanism of action of cytopiloyne and prove its therapeutic potential in T2D
Non-ideal optical isotropy of blue phase liquid crystal
Since 1981, blue phase liquid crystal (BPLC) was regarded as optical isotropy and high contrast ratio (CR) should be achieved easily. However, low CR of BPLC display was reported in all literatures. Here, we show BPLC is non-ideal optical isotropy which leads to poor CR. In our report, BPLC not only revealed primary structure of double-twist cylinder and secondary structure of lattice but also revealed tertiary structure of self-alignment on electrode surface. This finding will be useful to improve CR and inspire researches in display industry and academics
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