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The characterization of a wide range of luminescent thin films can be a long and tedious endeavor. With reactive combinatorial sputtering of multiple metal targets, it possible to fabricate thin films with a gradient in composition simply by not rotating the substrate. In this work, combinatorically sputtered thin films of Cr3+ and Nd3+ doped in the Al2O3–Y2O3 system (YAlO) are studied for thin film based luminescent solar concentrators (TFLSCs) application. Contrary to mm's thick plate type LSC's, TFLSCs of just several 100 nm thick require much higher Cr3+ concentration to achieve 40% absorption which can enable several 10's of W/m2 LSC power efficiencies. Our transmission measurements on a Cr2O3 film with a thickness gradient result in an absorption cross section at 460 nm of 1.3 ± 0.7 × 10−19 cm2 showing that the TFLSC absorption requirement can be fulfilled provided that the Cr3+ concentration is in the order of 1022 ions/cm3. The Y:Al ratio of the YAlO host in our films ranged between 0.5 and 3.5, thereby including the monoclinic (Y4Al2O9), perovskite (YAlO3) and garnet (Y3Al5O12) stoichiometry's on a single film. Position dependent XRD, EDX, excitation, emission and lifetime measurements of Cr3+ and Nd3+ show that the unique gradient film sputtering method is able to characterize thin films as a function of host composition and doping concentration. Energy transfer between Cr3+ and Nd3+ in co-doped YAlO films is concluded from Cr3+ excitation bands observed while monitoring Nd3+ emission and from the matching of the rise-time of Nd3+ 1340 nm emission (4F3/2 -> 4I11/2) and the decay time of Cr, RST/Luminescence Materials

The role of aortic clamping techniques on the occurrence of neurological complications after right mini-thoracotomy mitral valve surgery is still debated. Brain injuries can occur also as silent cerebral micro-embolizations (SCM), which have been linked to significant deficits in physical and cognitive functions. Aims of this study are to evaluate the overall rate of SCM and to compare endoaortic clamp (EAC) with trans-thoracic clamp (TTC). Patients enrolled underwent a pre-operative, a post-operative, and a follow-up MRI. Forty-three patients were enrolled; EAC was adopted in 21 patients, TTC in 22 patients. Post-operative SCM were reported in 12 cases (27.9%). No differences between the 2 groups were highlighted (23.8% SCM in the EAC group versus 31.8% in the TTC). MRI analysis showed post-operative SCM in nearly 30% of selected patients after right mini-thoracotomy mitral valve surgery. Subgroup analysis on different types of aortic clamping showed comparable results. Clinical Relevance: The rate of SCM reported in the present study on patients undergoing minimally invasive MVS and RAP is consistent with data in the literature on patients undergoing cardiac surgery through median sternotomy and antegrade arterial perfusion. Moreover, no differences were reported between EAC and TTC: both the aortic clamping techniques are safe, and the choice of the surgical setting to adopt can be really done according to the patient’s characteristics.

Social media platforms provide opportunities for users across the world to connect and communicate between them and engage into acts of social support and entertainment. Yet it can also bring negative consequences as it has been associated with poor mental health and life dissatisfaction. This underlines the importance of delivering social media literacy (SML) interventions that raise awareness of the dangers and threats that are hidden within. To this date, SML initiatives have shown their benefits towards the acquisition of SML skills through the forms of school interventions and mini-games. However, studies on promoting SML through social media platforms need to be also encouraged and innovative approaches to provide interactive scenarios with hands-on experiences need to be formulated. Hence, the project COURAGE introduces a new approach towards SML by proposing the integration of educational opportunities within a controlled social media platform. To provide students the opportunity to learn whilst they naturally explore social media we propose the integration of virtual learning companions. In this paper we report seven empirical approaches towards SML skills acquisition powered by virtual learning companions. The paper concludes with a discussion towards the benefits and limitations of using this type of SML interventions.

We present a digital media literacy activity composed of (i) an educational talk and (ii) a game-based activity. The aim is to support teachers in developing learning activities to increase awareness of social media threats among students. Through this activity students directly experience phenomena like echo chambers and filter bubbles that can be provoked by harmful online interaction dynamics controlled by social media platforms’ recommender systems while remaining invisible to the affected users. Our preliminary findings show that a game-based direct experience, inspired by the wisdom of crowds phenomenon, can increase the perception of social media influence on participants with statistically significant results compared to standard lecture-based activity. We conclude that developing a tool enabling educators and scholars to easily perform the proposed activity can be helpful to improve digital media literacy effectiveness.

Social media are offering new opportunities for communication and interaction way beyond what was possible only a few years ago. However, social media are also virtual spaces where young people are exposed to a variety of threats. Digital addiction, discrimination, hate speech, misinformation, polarization as well as manipulative influences of algorithms, body stereotyping, and cyberbullying are examples of challenges that find fertile ground on social media. Educators and students are not adequately prepared to face these challenges. To this aim, the COURAGE project, presented in this paper, introduces new tools and learning methodologies that can be adopted within higher education learning paths to train educators to deal with social media threats. The overarching principles of the COURAGE project leverage the most recent advances in the fields of artificial intelligence and in the educational domain paired with social and media psychological insights to support the development of the COURAGE ecosystem. The results of the experiments currently implemented with teachers and students of secondary schools as well as the impact of the COURAGE project on societal changes and ethical questions are presented and discussed.

The provision of toxic content and misinformation is a frequent phenomenon in current social media with specific impact and risks for younger users. We report on efforts taken in the project Courage to mitigate and overcome these threats through dedicated educational technology inspired by psychological and pedagogical approaches. The aim is to empower adolescents to confidently interact with and utilize social media and to increase their awareness and resilience. For this purpose, we have adopted approaches from the field of Intelligent Tutoring Systems, namely the provision of a virtual learning companion (VLC). The technical system is a browser-based environment that allows for combining a controllable social media space with a VLC as a plugin. This environment is backed by an API that bundles Machine Learning and Natural Language Processing algorithms for detecting and classifying different types of risks. The pedagogical scenarios that are supported by this technical environment and approach range from chat-based dialogues to more complex narrative scripts.

Silicon-aluminum-oxigen (SiAlO) coatings doped with Sm2+ and prepared by reactive magnetron co-sputtering of Si, Al, and Sm targets, are attractive for luminescence solar concentrator applications but suffer from the low absorption between 300 and 600 nm. This article reports that the main cause of low absorption is a high concentration of undesired Sm3+. This finding is supported by optical transmittance, photoluminescence emission and excitation characterization, and X-ray photoelectron spectroscopy data of the Sm's 3d5/2 edge. We present an alternative deposition process for obtaining Sm doped SiAlO layers with enhanced Sm2+ absorption by incorporating Sm through the use of multilayer thin-film precursors composed of metallic Sm and SiAlO layers. After thermal post-deposition treatments, diffusion and reaction of the metallic Sm layers with the SiAlO host results in coatings showing the characteristic 5d → 4f transitions of Sm2+ in the region between 250 and 600 nm which were not detectable in Sm-doped single layers. This same deposition strategy produces Tm doped SiAlO coatings with Tm2+‘s characteristic luminescence at 1132 nm when the SiAlO host is in the mullite composition region. The photoluminescence excitation spectrum of Tm2+ is compared to phosphor with similar composition and covers the range between 300 and 700 nm., RST/Luminescence Materials, QN/Afdelingsbureau, ChemE/O&O groep