“Too complex for me!” Why do performance-approach and performance-avoidance goals predict exam performance?

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High precision wavefront control in point spread function engineering for single emitter localization

Point spread function (PSF) engineering is used in single emitter localization to measure the emitter position in 3D and possibly other parameters such as the emission color or dipole orientation as well. Advanced PSF models such as spline fits to experimental PSFs or the vectorial PSF model can be used in the corresponding localization algorithms in order to model the intricate spot shape and deformations correctly. The complexity of the optical architecture and fit model makes PSF engineering approaches particularly sensitive to optical aberrations. Here, we present a calibration and alignment protocol for fluorescence microscopes equipped with a spatial light modulator (SLM) with the goal of establishing a wavefront error well below the diffraction limit for optimum application of complex engineered PSFs.We achieve high-precision wavefront control, to a level below 20 mλ wavefront aberration over a 30 minute time window after the calibration procedure, using a separate light path for calibrating the pixel-to-pixel variations of the SLM, and alignment of the SLM with respect to the optical axis and Fourier plane within 3 μm (x/y) and 100 μm (z) error. Aberrations are retrieved from a fit of the vectorial PSF model to a bead z-stack and compensated with a residual wavefront error comparable to the error of the SLM calibration step. This well-calibrated and corrected setup makes it possible to create complex '3D+λ' PSFs that fit very well to the vectorial PSF model. Proof-of-principle bead experiments show precisions below 10 nm in x, y, and λ, and below 20 nm in z over an axial range of 1 μm with 2000 signal photons and 12 background photons.ImPhys/OpleidingTechnische NatuurkundeApplied SciencesImPhys/Quantitative ImagingImPhys/Imaging Physic

The assessment of motivation for technology-based learning environments: The Italian version of the Achievement Goal Questionnaire-Revised

The increased use of technology within the educational field gives rise to the need of developing valid instruments enabling to measure key constructs in fast ways, often involving many people. Therefore, this work explored some psychometric properties\u2013in terms of factor structure and alpha coefficients\u2013of a first Italian version of the Achievement Goal Questionnaire-Revised [8], as a first step preceding a future computerized implementation of the instrument. Seventy-seven university students completed the questionnaire, referring to a specific course. Each questionnaire included 12 items, three for each goal: Mastery-approach, mastery-avoidance, performance-approach, and performance-avoidance goals. Confirmative factor analyses indicated the goodness of the hypothesized model, and its superiority compared to several alternative models; also alpha coefficients resulted adequate. These findings supported the validity of the adapted instrument, and were discussed considering possible future uses to assess motivational outcomes related to learning tasks within computer-based environments

Functionally defined therapeutic targets in diffuse intrinsic pontine glioma

Diffuse Intrinsic Pontine Glioma (DIPG) is a fatal childhood cancer. We performed a chemical screen in patient-derived DIPG cultures along with RNAseq analyses and integrated computational modeling to identify potentially effective therapeutic strategies. The multi-histone deacetylase inhibitor panobinostat demonstrated efficacy in vitro and in DIPG orthotopic xenograft models. Combination testing of panobinostat with histone demethylase inhibitor GSKJ4 revealed synergy. Together, these data suggest a promising therapeutic strategy for DIPG