3,656 research outputs found

    The relationship between propositional teacher knowledge and classroom teaching practice:The case of Chinese novice mathematics teachers

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    Propositional teacher knowledge is recognised as valuable in classroom teaching practice, yet little attention has been paid to it relative to practical knowledge. This mixed-methods study aimed to understand the relationship between teachers’ propositional knowledge and their classroom teaching practice in the collaborative school context using the case of Chinese (Shanghai) novice secondary mathematics teachers. The first quantitative phase, analysing 95 teachers from the 2018 TALIS, finds that propositional Mathematics Pedagogical Content Knowledge (MPCK), General Pedagogy Knowledge (GPK) and Cross-curricular Teaching Knowledge (CTK) positively relate to effective teaching practice. The qualitative follow-up phase, interviewing six teachers with secondary mathematics teaching experience, suggests the value of propositional knowledge in three other areas, including Mathematical Content Knowledge (MCK), Curriculum Knowledge (CK), and Technological Pedagogical Content Knowledge (TPCK), as well as possible barriers in transforming propositional knowledge into practical knowledge. Overall results suggest that a collaborative school context aids this transition, helping teachers develop their practical knowledge to enhance the effectiveness of their teaching.</p

    A combination of plasma DAO and citrulline levels as a potential marker for acute mesenteric ischemia

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    Introduction: There is no valid and reliable diagnostic test for early  diagnosis of acute mesenteric ischemia (AMI). The aim of this study was to measure the plasma levels of diamine oxidase (DAO) and citrulline inAMI to gain insight into its early diagnosis.Material and methods: A total of 21 Wistar albino rats were divided into three groups, that is, control group, short-term ischemia group, and prolonged ischemia group. The superior mesenteric artery was occluded for15 min in the short-term ischemia group and for 12 h in the prolonged ischemia group. Twelve hours later, the experiment was terminated and plasma DAO and citrulline levels were measured. Intestinal tissue wasevaluated for the histopathological changes.Results: Compared to the control group, the short-term and prolonged ischemia groups showed significant increases in the plasma levels of DAO, whereas the plasma citrulline levels decreased significantly. Prolongedischemia caused a larger increase in the plasma DAO levels and a larger decrease in the plasma citrulline levels compared to the short-term ischemia (p0.011 and p0.021, respectively). Intestinal damage was shown to develop more in the prolonged ischemia group (p0.001).Conclusion: In the early period of AMI, the plasma DAO levels increase while citrulline levels decrease, and the extent of these changes depends on the duration of ischemia.Keywords: animal model; experimental; intestines; diamine oxidase; citrullin

    A Hybrid 3D/2D Field Response Calculation for Liquid Argon Detectors with PCB Based Anode Plane

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    Liquid Argon Time Projection Chamber (LArTPC) technology is commonly utilized in neutrino detector designs. It enables detailed reconstruction of neutrino events with high spatial precision and low energy threshold. Its field response (FR) model describes the time-dependent electric currents induced in the anode-plane electrodes when ionization electrons drift nearby. An accurate and precise FR is a crucial input to LArTPC detector simulations and charge reconstruction. Established LArTPC designs have been based on parallel wire planes. It allows accurate and computationally economic two-dimensional (2D) FR models utilizing the translational symmetry along the direction of the wires. Recently, novel LArTPC designs utilize electrodes formed on printed circuit board (PCB) in the shape of strips with through holes. The translational symmetry is no longer a good approximation near the electrodes and a new FR calculation that employs regions with three dimensions (3D) has been developed. Extending the 2D models to 3D would be computationally expensive. Fortuitously, the nature of strips with through holes allows for a computationally economic approach based on the finite-difference method (FDM). In this paper, we present a new software package "pochoir" that calculates LArTPC field response for these new strip-based anode designs. This package combines 3D calculations in the volume near the electrodes with 2D far-field solutions to achieve fast and precise field response computation. We apply the resulting FR to simulate and reconstruct samples of cosmic-ray muons and 39^{39}Ar decays from a Vertical Drift (VD) detector prototype operated at CERN. We find the difference between real and simulated data within 5 %. Current state-of-the-art LArTPC software requires a 2D FR which we provide by averaging over one dimension and estimate that variations lost in this average are smaller than 7 %.Comment: 16 pages, 12 figure

    Position-specific Performance Indicators that Discriminate between Successful and Unsuccessful Teams in Elite Women’s Indoor Field Hockey: Implications for Coaching

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    The aim of this investigation was to establish median performance profiles for the six playing positions in elite women’s indoor hockey and then identify whether these position-specific profiles could discriminate between qualifying (top four), mid-table and relegated teams in the 2011-12 England Hockey premier league. Successful passing in relegated teams was significantly lower (p<0.008) than in mid-table and qualifying teams in four of the five outfield positions. Furthermore, the right backs of qualifying teams demonstrated significantly fewer (p<0.008) unsuccessful passes (x̃=15.5 ±CLs 15.0 and 10.0 respectively) and interceptions (x̃=4.0 ±CLs 4.0 and 3.0 respectively) than relegated teams (x̃=19.5 ±CLs 21.0 and 17.0; x̃=7.5 ±CLs 8.0 and 6.0 respectively). Finally, the right forwards of relegated teams demonstrated significantly fewer (p<0.008) successful interceptions (x̃=4.0 ±CLs 5.0 and 4.0 respectively) than qualifying teams (x̃=5.0 ±CLs 6.0 and 3.0 respectively) and significantly more (p<0.008) unsuccessful interceptions (x̃=5.5 ±CLs 6.0 and 4.0 respectively) than mid-table teams (x̃=3.0 ±CLs 3.0 and 2.0 respectively). Based on these findings, coaches should adapt tactical strategies and personnel deployment accordingly to enhance the likelihood of preparing a qualifying team. Research should build from these data to examine dribbling, pressing and patterns of play when outletting

    Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

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    The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum

    Dolphin morbillivirus infection in different parts of the Mediterranean Sea

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    Morbillivirus were isolated from Mediterranean striped dolphins (Stenella coeruleoalba) dying along the coasts of Italy and Greece in 1991. They were antigenically identical to the morbilliviruses isolated from striped dolphins in Spain in 1990
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