Three Saturn-mass planets transiting F-type stars revealed with TESS and HARPS

While the sample of confirmed exoplanets continues to increase, the population of transiting exoplanets around early-type stars is still limited. These planets allow us to investigate the planet properties and formation pathways over a wide range of stellar masses and study the impact of high irradiation on hot Jupiters orbiting such stars. We report the discovery of TOI-615b, TOI-622b, and TOI-2641b, three Saturn-mass planets transiting main sequence, F-type stars. The planets were identified by the Transiting Exoplanet Survey Satellite (TESS) and confirmed with complementary ground-based and radial velocity observations. TOI-615b is a highly irradiated ($\sim$1277 $F_{\oplus}$) and bloated Saturn-mass planet (1.69$^{+0.05}_{-0.06}$$R_{Jup}$ and 0.43$^{+0.09}_{-0.08}$$M_{Jup}$) in a 4.66 day orbit transiting a 6850 K star. TOI-622b has a radius of 0.82$^{+0.03}_{-0.03}$$R_{Jup}$ and a mass of 0.30$^{+0.07}_{-0.08}$~$M_{Jup}$ in a 6.40 day orbit. Despite its high insolation flux ($\sim$600 $F_{\oplus}$), TOI-622b does not show any evidence of radius inflation. TOI-2641b is a 0.37$^{+0.05}_{-0.04}$$M_{Jup}$ planet in a 4.88 day orbit with a grazing transit (b = 1.04$^{+0.05}_{-0.06 }$) that results in a poorly constrained radius of 1.61$^{+0.46}_{-0.64}$$R_{Jup}$. Additionally, TOI-615b is considered attractive for atmospheric studies via transmission spectroscopy with ground-based spectrographs and $\textit{JWST}$. Future atmospheric and spin-orbit alignment observations are essential since they can provide information on the atmospheric composition, formation and migration of exoplanets across various stellar types.Comment: 16 pages, 17 figures, submitted to A&

Additive manufacturing of cobalt-based dental alloys: analysis of microstructure and physicomechanical properties

The limitations of investment casting of cobalt-based alloys are claimed to be less problematic with significant improvements in metal additive manufacturing by selective laser melting (SLM). Despite these advantages, the metallic devices are likely to display mechanical anisotropy in relation to build orientations, which could consequently affect their performance "in vivo." In addition, there is inconclusive evidence concerning the requisite composition and postprocessing steps (e.g., heat treatment to relieve stress) that must be completed prior to using the devices. In the current paper, we evaluate the microstructure of ternary cobalt-chromium-molybdenum (Co-Cr-Mo) and cobalt-chromium-tungsten (Co-Cr-W) alloys built with direct metal printing and LaserCUSING SLM systems, respectively, at 0°, 30°, 60°, and 90° inclinations (Φ) in as-built (AB) and heat-treated (HT) conditions. The study also examines the tensile properties (Young's modulus, E; yield strength, R; elongation at failure, A; and ultimate tensile strength, R), relative density (RD), and microhardness (HV5) and macrohardness (HV20) as relevant physicomechanical properties of the alloys. Data obtained indicate improved tensile properties and HV values after a short and cost-effective heat-treatment cycle of Co-Cr-Mo alloys; however, the process did not homogenize the microstructure of the alloy. Annealing heat treatment of Co-Cr-W led to significant isotropic characteristics with increased E and A (except for Φ = 90°) in contrast to decreased R, R, and HV values, compared to the AB form. Similarly, the interlaced weld-bead structures in AB Co-Cr-W were removed during heat treatment, which led to a complete recrystallization of the microstructure. Both alloys exhibited defect-free microstructures with RD exceeding 99.5%

Facilitating Diagnostic Competences in Simulations in Higher Education: A Framework and a Research Agenda

Diagnosis is a prerequisite for successful professional problem-solving: A physician identifies an appropriate treatment based on a diagnosis of the patient’s disease, and a teacher selects an appropriate learning task based on an assessment of the student’s prior knowledge. Education in academic professions such as medicine or teaching is often focuses on the acquisition of conceptual knowledge from lectures and books; opportunities for students to engage in practical diagnostic situations are typically rare. However, applying such conceptual knowledge in diagnostic activities is regarded as necessary for developing diagnostic competences. In this article, we focus on simulations in which students can actively engage in practicing diagnostic activities concerning cases from professional practice. We review and link research perspectives on diagnostic competences, their components and their development. This is partly done by exploring the commonalities and differences in research on diagnostic competences in medicine and teaching. Then, we present approaches to simulation, followed by different types of instructional support in such simulations. In particular, we focus on different forms of scaffolding during problem-solving, and on the possibly complementary roles of expository forms of instruction in these kinds of environments. Building on the perspectives reviewed, we propose a framework for fostering diagnostic competences in simulations in higher education and outline an interdisciplinary research approach concerning the instructional design of such simulations

Representational scaffolding in digital simulations – learning professional practices in higher education

To advance the learning of professional practices in teacher education and medical education, this conceptual paper introduces the idea of representational scaffolding for digital simulations in higher education. We outline the ideas of core practices in two important fields of higher education, namely teacher and medical education. To facilitate future professionals’ learning of relevant practices, we emphasize the role of approximation of practice through the use of digital simulations, as they offer multiple options for selecting and adjusting representations of practice situations. Furthermore, we introduce the idea of representational scaffolding to adjust the demands of the learning task in simulations by selecting and modifying representations of practice to match relevant learner characteristics. Building on research on problem-solving and scientific reasoning, we identify leverage points for employing representational scaffolding. We suggest four sets of representational scaffolds that target relevant features of practice situations in simulations: informational complexity, typicality, required agency, and situation dynamics. Representational scaffolds might be implemented in a strategy for approximating practice that involves the media design, sequencing, and adaptation of representational scaffolding. The outlined conceptualization of representational scaffolding can systematize the design and adaptation of digital simulations in higher education and might contribute to the advancement of future professionals’ learning to further engage in professional practices. This conceptual paper offers a necessary foundation and terminology for approaching related future research. https://doi.org/10.1108/ILS-06-2022-007