14,118 research outputs found

    The structure of teaching practices across countries. A combination of factor analysis and network analysis

    Get PDF
    Teaching practices are pivotal for student learning. Due to pedagogical traditions and national cultures, the structure of teaching practices may differ across countries. This study investigates the structure of teaching practices across 12 countries grouped into four major linguistic/cultural clusters. First, factor analysis is applied to investigate if the theoretical distinction between teacher-directed and student-centred practices is generalizable across countries. Then, network analysis is used to explore how individual classroom assessment practices relate to either teacher-directed or student-centred practices. Main findings include that: (1) teacher-directed and student-centred practices are two distinct factors across countries; (2) the overall structure and connectivity of teaching practices differs across countries, with smaller differences within linguistic/cultural clusters; and (3) assessment practices with the aim to structure and guide learning strongly relate to teacher-directed practices, whereas assessment practices with the aim to individualize instruction more relate to student-centred practices. We discuss the global patterning and implications

    Haplotype analysis of the PPARgamma Pro12Ala and C1431T variants reveals opposing associations with body weight.

    Get PDF
    BACKGROUND: Variation at the PPARG locus may influence susceptibility to type 2 diabetes and related traits. The Pro12Ala polymorphism may modulate receptor activity and is associated with protection from type 2 diabetes. However, there have been inconsistent reports of its association with obesity. The silent C1431T polymorphism has not been as extensively studied, but the rare T allele has also been inconsistently linked to increases in weight. Both rare alleles are in linkage disequilibrium and the independent associations of these two polymorphisms have not been addressed. RESULTS: We have genotyped a large population with type 2 diabetes (n = 1107), two populations of non-diabetics from Glasgow (n = 186) and Dundee (n = 254) and also a healthy group undergoing physical training (n = 148) and investigated the association of genotype with body mass index. This analysis has demonstrated that the Ala12 and T1431 alleles are present together in approximately 70% of the carriers. By considering the other 30% of individuals with haplotypes that only carry one of these polymorphisms, we have demonstrated that the Ala12 allele is consistently associated with a lower BMI, whilst the T1431 allele is consistently associated with higher BMI. CONCLUSION: This study has therefore revealed an opposing interaction of these polymorphisms, which may help to explain previous inconsistencies in the association of PPARG polymorphisms and body weight

    Rare decay π0e+e\pi^{0}\to e^+ e^- constraints on the light CP-odd Higgs in NMSSM

    Get PDF
    We constrain the light CP-odd Higgs A10A_{1}^{0} in NMSSM via the rare decay π0e+e\pi^{0}\to e^{+}e^{-}. It is shown that the possible 3σ3\sigma discrepancy between theoretical predictions and the recent KTeV measurement of B(π0e+e){\cal B}({\pi}^{0}\to e^+ e^-) cannot be resolved when the constraints from ΥγA10\Upsilon\to\gamma A_1^0, aμa_{\mu} and π0γγ\pi^{0}\to \gamma \gamma are combined. Furthermore, the combined constraints also exclude the scenario involving mA10=214.3m_{A_1^0}=214.3 MeV, which is invoked to explain the anomaly in the Σ+pμ+μ\Sigma^{+}\to p \mu^{+}\mu^{-} decay found by the HyperCP Collaboration.Comment: 16 pages, 5 figures. Title changed, pi-A mixing included. Version to appear in PL

    Quality control in clinical raster-scan optoacoustic mesoscopy

    Get PDF
    Optoacoustic (photoacoustic) mesoscopy bridges the gap between optoacoustic microscopy and macroscopy and enables high-resolution visualization deeper than optical microscopy. Nevertheless, as images may be affected by motion and noise, it is critical to develop methodologies that offer standardization and quality control to ensure that high-quality datasets are reproducibly obtained from patient scans. Such development is particularly important for ensuring reliability in applying machine learning methods or for reliably measuring disease biomarkers. We propose herein a quality control scheme to assess the quality of data collected. A reference scan of a suture phantom is performed to characterize the system noise level before each raster-scan optoacoustic mesoscopy (RSOM) measurement. Using the recorded RSOM data, we develop a method that estimates the amount of motion in the raw data. These motion metrics are employed to classify the quality of raw data collected and derive a quality assessment index (QASIN) for each raw measurement. Using simulations, we propose a selection criterion of images with sufficient QASIN, leading to the compilation of RSOM datasets with consistent quality. Using 160 RSOM measurements from healthy volunteers, we show that RSOM images that were selected using QASIN were of higher quality and fidelity compared to non-selected images. We discuss how this quality control scheme can enable the standardization of RSOM images for clinical and biomedical applicationsThis project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 871763 (WINTHER) and under grant agreement No 687866 (INNODERM). Dr. He would like to thank the Helmholtz Imaging Platform (HIP: Deep4OM). Dr. Aguirre would like to thank support from the Madrid Autonomous Region Talento Project 2020-T1/TIC-2066

    IL-4 and T cells are required for the generation of IgG1 isotype antibodies against cardiolipin.

    No full text
    Infection with Mycobacterium tuberculosis induces Abs against a vast array of mycobacterial lipids and glycolipids. One of the most prominent lipid Ags recognized is cardiolipin (CL). The kinetics of the generation of anti-CL Abs during infection reveals that IgM titers to CL increase over time. Interestingly, at day 30 postinfection CL-specific IgG1 appears, an isotype usually dependent on T cell help. Using an immunization schedule with CL/anti-CL Ab complexes, which induces antiphospholipid syndrome in mice, we show that the generation of IgG1 to CL requires IL-4 and that optimal production is T cell dependent. IgG1 production to CL was impaired in nude (nu/nu) mice devoid in conventional T cells, but was not affected in mice deficient for either alphabeta TCR(+), gammadelta TCR(+), CD4(+), CD8(+), or NK1.1(+) T cells. We conclude that IgG1 production to CL depends on T cell help and IL-4, which can be provided by different T cell populations. This is the first report that IL-4 is indispensable for the induction of IgG1 Abs to lipid Ags

    Performance study of global weight window generator based on particle density uniformity

    Get PDF
    The variance reduction techniques are necessary for Monte Carlo calculations in which obtaining a detailed calculation result for a large and complex model is required. The GVR method named as global weight window generator (GWWG) was proposed by the FDS team. In this paper, two typical calculation examples, ISPRA-Fe benchmark in SINBAD (Shielding Integral Benchmark Archive Database) and TF Coils (Toroidal Field coils) of European HCPB DEMO (Helium Cooled Pebble Bed demonstration fusion plant), are used to study the performance of GWWG method. It can be seen from the calculation results that the GWWG method has a significant effect in accelerating the Monte Carlo calculation. Especially when the global convergence calculation results are needed, the acceleration effect (FOMG) can reach 105^{5} or more. It proves that the GWWG method is an effective tool for deep-penetration simulations using Monte Carlo method

    Benzyltriphenylphosphonium perchlorate

    Full text link
    corecore