633 research outputs found

    Do social cues in instructional videos affect attention allocation, perceived cognitive load, and learning outcomes under different visual complexity conditions?

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    Background:There are only few guidelines on how instructional videos should be designed to optimize learning. Recently, the effects of social cues on attention allocation and learning in instructional videos have been investigated. Due to inconsistent results, it has been suggested that the visual complexity of a video influences the effect of social cues on learning.Objectives:Therefore, this study compared the effects of social cues (i.e., gaze & gesture) in low and high visual complexity videos on attention, perceived cognitive load,and learning outcomes.Methods:Participants (N=71) were allocated to a social cue or no social cue condition and watched both a low and a high visual complexity video. After each video, participants completed a knowledge test.Results and Conclusions: Results showed that participants looked faster at referenced information and had higher learning outcomes in the low visual complexity condition. Social cues did not affect any of the dependent variables, except when including prior knowledge in the analysis: In this exploratory analysis, the inclusion of gaze and gesture cues in the videos did lead to better learning outcomes.Takeaways: Our results show that the visual complexity of instructional videos and prior knowledge are important to take into account in future research on attention and learning from instructional videos

    Itinéraire d’une œuvre

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    Generation of a stable, soluble mimic of the HIV-1 envelope glycoprotein (Env) trimer on the virion surface has been considered an important first step for developing a successful HIV-1 vaccine. Recently, a soluble native-like Env trimer (BG505 SOSIP.664) has been described. This protein has facilitated major advances in the HIV-1 vaccine field, since it was the first Env immunogen that induced consistent neutralizing antibodies against a neutralization-resistant (tier 2) virus. Moreover, BG505 SOSIP.664 enabled elucidation of the atomic resolution structure of the Env trimer and facilitated the isolation and characterization of new broadly neutralizing antibodies against HIV-1. Here, we designed and characterized the BG505 SOSIP.664 trimer fused to fluorescent superfolder GFP (sfGFP), a GFP variant that allows efficient folding (BG505 SOSIP.664-sfGFP). Despite the presence of the sfGFP, the Env protein largely retained its morphology, antigenicity, glycan composition, and thermostability. In addition, we show that BG505 SOSIP.664-sfGFP can be used for fluorescence-based assays, such as flow cytometry.</p

    Structure of the Cytoplasmic Loop between Putative Helices II and III of the Mannitol Permease of Escherichia coli: A Tryptophan and 5-Fluorotryptophan Spectroscopy Study

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    In this work, four single tryptophan (Trp) mutants of the dimeric mannitol transporter of Escherichia coli, EIImtl, are characterized using Trp and 5-fluoroTrp (5-FTrp) fluorescence spectroscopy. The four positions, 97, 114, 126, and 133, are located in a region shown by recent studies to be involved in the mannitol translocation process. To spectroscopically distinguish between the Trp positions in each subunit of dimeric EIImtl, 5-FTrp was biosynthetically incorporated because of its much simpler photophysics compared to those of Trp. The steady-state and time-resolved fluorescence methodologies used point out that all four positions are in structured environments, both in the absence and in the presence of a saturating concentration of mannitol. The fluorescence decay of all 5-FTrp-containing mutants was highly homogeneous, suggesting similar microenvironments for both probes per dimer. However, Stern-Volmer quenching experiments using potassium iodide indicate different solvent accessibilities for the two probes at positions 97 and 133. A 5 Ã… two-dimensional (2D) projection map of the membrane-embedded IICmtl dimer showing 2-fold symmetry is available. The results of this work are in better agreement with a 7 Ã… projection map from a single 2D crystal on which no symmetry was imposed.

    Structure-Enabled Discovery of a Stapled Peptide Inhibitor to Target the Oncogenic Transcriptional Repressor TLE1.

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    TLE1 is an oncogenic transcriptional co-repressor that exerts its repressive effects through binding of transcription factors. Inhibition of this protein-protein interaction represents a putative cancer target, but no small-molecule inhibitors have been published for this challenging interface. Herein, the structure-enabled design and synthesis of a constrained peptide inhibitor of TLE1 is reported. The design features the introduction of a four-carbon-atom linker into the peptide epitope found in many TLE1 binding partners. A concise synthetic route to a proof-of-concept peptide, cycFWRPW, has been developed. Biophysical testing by isothermal titration calorimetry and thermal shift assays showed that, although the constrained peptide bound potently, it had an approximately five-fold higher Kd than that of the unconstrained peptide. The co-crystal structure suggested that the reduced affinity was likely to be due to a small shift of one side chain, relative to the otherwise well-conserved conformation of the acyclic peptide. This work describes a constrained peptide inhibitor that may serve as the basis for improved inhibitors

    Increased aortic stiffness and blood pressure in non-classic Pompe disease

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    Vascular abnormalities and glycogen accumulation in vascular smooth muscle fibres have been described in Pompe disease. Using carotid-femoral pulse wave velocity (cfPWV), the gold standard methodology for determining aortic stiffness, we studied whether aortic stiffness is increased in patients with Pompe disease. Eighty-four adult Pompe patients and 179 age- and gender-matched volunteers participated in this cross-sectional case-controlled study. Intima media thickness and the distensibility of the right common carotid artery were measured using a Duplex scanner. Aortic augmentation index, central pulse pressure, aortic reflexion time and cfPWV were assessed using the SphygmoCor® system. CfPWV was higher in patients than in volunteers (8.8 versus 7.4 m/s, p < 0.001). This difference was still present after adjustment for age, gender, mean arterial blood pressure (MAP), heart rate and diabetes mellitus (p = 0.001), and was shown by subgroup analysis to apply to the 40-59 years age group (p = 0.004) and 60+ years age group (p = 0.01), but not to younger age groups (p = 0.99)

    Goed bestuur in uitvoering: de praktijk van onderwijsinstellingen, woningcorporaties, zorgorganisaties en samenwerkingsverbanden

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    De Algemene Rekenkamer heeft een achtergrondstudie uitgevoerd over goed bestuur in praktijk van instellingen die binnen het publieke domein opereren. We hebben gekeken naar organisaties in de onderwijssector, de zorgsector en de huisvestingssector. Daarnaast hebben we aandacht besteed aan instellingen die samenwerkingsverbanden aangaan en sectorgrenzen overschrijden. We hebben ons geconcentreerd op de twee aspecten van goed bestuur waarvoor zowel de beleidsmakers als de instellingen zelf de meeste belangstelling hebben: het interne toezicht en de omgang met belanghebbenden
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