2,677 research outputs found

    Effects of English Teaching with Interactive Whiteboards in the Elementary English Classrooms

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    The purpose of the study was to probe the effectiveness of English language teaching through Interactive Whiteboards (IWBs). Three specific factors were probed: (a) the results from immediate test and retention test; (b) students’ perceptions related to the utilization of IWBs; (c) the advantages and disadvantages of the technology-supported instruction. Forty-three students from Grade 3 students in Sahes Elementary School in Taiwan were engaged in either technology-supported group or none technology-supported group. The results revealed that the experimental group through technology-supported instruction significantly outperformed the control group on students’ immediate test and retention test. Moreover, students’ perceptions related to the IWBs indicated that most of them enjoying learning English in the technology-supported classrooms. Finally, the results also showed the advantages and disadvantages through the IWBs instructions. The study revealed that teaching through technology was an effective way to help students in English learning

    Flow Generated by a Suddenly Heated Flat Plate

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    By employing the two-sided Maxwellian in Maxwell's moment method a kinetic theory description is obtained of the flow generated by a step-function increase in the temperature of an infinite flat plate. Four moments are employed in order to satisfy the three conservation equations, plus one additional equation involving the heat flux in the direction normal to the plate. For a small temperature rise the equations are linearized, and closed-form solutions are obtained for small and large time in terms of the average collision time. Initially the disturbances propagate along two distinct characteristics, but the discontinuities across these waves damp out as time increases. At large time the main disturbance propagates with the isentropic sound speed. Solutions for mean normal velocity and temperature show the transition from the nearly collision-free regime to the Navier-Stokes-Fourier regime, which is characterized by a boundary layer near the plate surface merging into a diffuse "wave". The classical continuum equations, plus a temperature jump boundary condition, seem to be perfectly adequate to describe the flow beyond a few collision times, provided one accounts properly for the interaction between the inner thermal layer and the outer diffuse wave

    Physicochemical studies of adsorptive denitrogenation by oxidized activated carbons

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    The effects of rear-wheel camber on the kinematics of upper extremity during wheelchair propulsion

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    BACKGROUND: The rear-wheel camber, defined as the inclination of the rear wheels, is usually used in wheelchair sports, but it is becoming increasingly employed in daily propulsion. Although the rear-wheel camber can increase stability, it alters physiological performance during propulsion. The purpose of the study is to investigate the effects of rear-wheel cambers on temporal-spatial parameters, joint angles, and propulsion patterns. METHODS: Twelve inexperienced subjects (22.3±1.6 yr) participated in the study. None had musculoskeletal disorders in their upper extremities. An eight-camera motion capture system was used to collect the three-dimensional trajectory data of markers attached to the wheelchair-user system during propulsion. All participants propelled the same wheelchair, which had an instrumented wheel with cambers of 0°, 9°, and 15°, respectively, at an average velocity of 1 m/s. RESULTS: The results show that the rear-wheel camber significantly affects the average acceleration, maximum end angle, trunk movement, elbow joint movement, wrist joint movement, and propulsion pattern. The effects are especially significant between 0° and 15°. For a 15° camber, the average acceleration and joint peak angles significantly increased (p < 0.01). A single loop pattern (SLOP) was adopted by most of the subjects. CONCLUSIONS: The rear-wheel camber affects propulsion patterns and joint range of motion. When choosing a wheelchair with camber adjustment, the increase of joint movements and the base of support should be taken into consideration

    Conserved Extracellular Cysteines Differentially Regulate the Potentiation Produced by Zn2+ in Rat P2X4 Receptors

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    One feature of the amino acid sequence of P2X receptors identified from mammalian species, Xenopus laevis and zebrafish is the conservation of ten cysteines in the extracellular loop. Little information is available about the role of these conserved ectodomain cysteines in the function of P2X receptors. Here, we investigated the possibility that ten conserved cysteine residues in the extracellular loop of the rat P2X4 receptor may regulate zinc potentiation of the receptor using a series of individual cysteine to alanine point mutations and functional characterization of recombinant receptors expressed in Xenopus oocytes. For the C116A, C132A, C159A, C165A, C217A and C227A mutants, 10 µM zinc did not significantly affect the current activated by an EC40 concentration of ATP. By contrast, 5 µM zinc shifted the ATP concentration-response curve to the right in a parallel manner for both the C261A and C270A mutants and the magnitudes of those shifts were similar to that of the wildtype receptor. Interestingly, for the C126A and C149A mutants, 5 µM zinc potentiated ATP-activated current, but increased the maximal response to ATP by 90% and 81% respectively, without significantly changing the EC50 value of ATP. Thus, these results suggest that cysteines and disulfide bonds between cysteines are differentially involved in the potentiation of the rat P2X4 receptor by zinc

    THE STUDY OF SHOULDER INTERNAL AND EXTERNAL ROTATION STRENGTH IN COLLEGE BASEBALL PLAYERS

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    The purpose of this study was to investigate the different of dominant arm shoulder rotation torque between the baseball pitchers, infielders, and ouffielders. Participants were 27 first-level collegiate baseball players, including 9 pitchers, 10 infielders, 8 outfielders. A Biodex lsokinetic Dynamometer was used for estimation of shoulder muscle strength. This system's test velocity was set at 60 "Is and the range of motion of dominant arm shoulder in flexion, abduction, 90' of abduction with external rotation, and 90" abduction with internal rotation. The results indicated that there was no significant different in internal rotation peak torque and ERllR ratio between pitchers, infielders, and outfielders. There was significantly different in external rotation peak torque. The infielders and ouffielders possess greater external rotation peak torque than pitchers

    Retrospective study of necrotizing fasciitis and characterization of its associated Methicillin-resistant Staphylococcus aureus in Taiwan

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    <p>Abstract</p> <p>Background</p> <p>Methicillin-resistant <it>Staphylococcus aureus </it>(MRSA) has emerged as a prevalent pathogen of necrotizing fasciitis (NF) in Taiwan. A four-year NF cases and clinical and genetic differences between hospital acquired (HA)- and community-acquired (CA)-MRSA infection and isolates were investigated.</p> <p>Methods</p> <p>A retrospective study of 247 NF cases in 2004-2008 and antimicrobial susceptibilities, staphylococcal chromosomal cassette <it>mec </it>(SCC<it>mec</it>) types, pulsed field gel electrophoresis (PFGE) patterns, virulence factors, and multilocus sequence typing (MLST) of 16 NF-associated MRSA in 2008 were also evaluated.</p> <p>Results</p> <p>In 247 cases, 42 microbial species were identified. <it>S. aureus </it>was the major prevalent pathogen and MRSA accounted for 19.8% of NF cases. Most patients had many coexisting medical conditions, including diabetes mellitus, followed by hypertension, chronic azotemia and chronic hepatic disease in order of decreasing prevalence. Patients with MRSA infection tended to have more severe clinical outcomes in terms of amputation rate (p < 0.05) and reconstruction rate (p = 0.001) than those with methicillin-sensitive <it>S. aureus </it>or non-<it>S. aureus </it>infection. NF patients infected by HA-MRSA had a significantly higher amputation rate, comorbidity, C-reactive protein level, and involvement of lower extremity than those infected by CA-MRSA. In addition to over 90% of MRSA resistant to erythromycin and clindamycin, HA-MRSA was more resistant than CA-MRSA to trimethoprim-sulfamethoxazole (45.8% <it>vs</it>. 4%). ST59/pulsotype C/SCC<it>mec </it>IV and ST239/pulsotype A/SCC<it>mec </it>III isolates were the most prevalent CA- and HA-MRSA, respectively in 16 isolates obtained in 2008. In contrast to the gene for γ-hemolysin found in all MRSA, the gene for Panton-Valentine leukocidin was only identified in ST59 MRSA isolates. Other three virulence factors TSST-1, ETA, and ETB were occasionally identified in MRSA isolates tested.</p> <p>Conclusion</p> <p>NF patients with MRSA infection, especially HA-MRSA infection, had more severe clinical outcomes than those infected by other microbial. The prevalent NF-associated MRSA clones in Taiwan differed distinctly from the most predominant NF-associated USA300 CA-MRSA clone in the USA. Initial empiric antimicrobials with a broad coverage for MRSA should be considered in the treatment of NF patients in an endemic area.</p

    Structural study in Highly Compressed BiFeO3 Epitaxial Thin Films on YAlO3

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    We report a study on the thermodynamic stability and structure analysis of the epitaxial BiFeO3 (BFO) thin films grown on YAlO3 (YAO) substrate. First we observe a phase transition of MC-MA-T occurs in thin sample (<60 nm) with an utter tetragonal-like phase (denoted as MII here) with a large c/a ratio (~1.23). Specifically, MII phase transition process refers to the structural evolution from a monoclinic MC structure at room temperature to a monoclinic MA at higher temperature (150oC) and eventually to a presence of nearly tetragonal structure above 275oC. This phase transition is further confirmed by the piezoforce microscopy measurement, which shows the rotation of polarization axis during the phase transition. A systematic study on structural evolution with thickness to elucidate the impact of strain state is performed. We note that the YAO substrate can serve as a felicitous base for growing T-like BFO because this phase stably exists in very thick film. Thick BFO films grown on YAO substrate exhibit a typical "morphotropic-phase-boundary"-like feature with coexisting multiple phases (MII, MI, and R) and a periodic stripe-like topography. A discrepancy of arrayed stripe morphology in different direction on YAO substrate due to the anisotropic strain suggests a possibility to tune the MPB-like region. Our study provides more insights to understand the strain mediated phase co-existence in multiferroic BFO system.Comment: 18 pages, 6 figures, submitted to Journal of Applied Physic
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