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Few studies have explored the learning difficulties and misconceptions that students encounter when using information and communication technology for e-learning. To address this issue, this research developed a system for evaluating the learning efficiency of medical students by applying two-tier diagnosis assessment. The effectiveness of the proposed system was evaluated in 11 resident doctors of dermatology enrolled according to a one-group pre- and post-test experimental design. After using the proposed e-learning system, the resident doctors had significantly improved learning efficiency and high satisfaction with the system functions. Although the number of subjects in this study was low, the significant improvements in clinical skills observed at the end of the educational training program indicate that the proposed integrated e-learning system is user-friendly and effective for self-education in the diagnosis skills required by medical students and dermatology residents.

Ion irradiation has emerged as a powerful tool for the efficient control of uniaxial lattice expansion to fine tune and modulate the otherwise inaccessible complex correlated phases in oxide thin-films. We report the fine tuning of the magnetic moment, ferromagnetic-paramagnetic and metal-insulator transition temperatures in the NiCo2O4 inverse-spinel oxide by creating oxygen deficiencies, employing high energy He-ion irradiation. Tailoring of oxygen vacancies and consequently a uniaxial lattice expansion in the out-of-plane direction drives the system toward the increase of the magnetic moment by two-times in magnitude. The magnetic moment increases with the He-ion irradiation fluence up to 2.5 × 1 0 16 / cm 2 . Our results are corroborated well by spin-polarized electronic structure calculations with density functional theory and X-ray absorption spectroscopic data, which show peak-height change and energy shift of Co-L2,3 and Ni-L2,3 edges driven by the oxygen vacancies. These results demonstrate a new pathway of tailoring oxygen vacancies via He-ion irradiation, useful for designing new functionalities in other complex oxide thin-films. [ABSTRACT FROM AUTHOR]

Superlattices are of great importance due to their potential as new materials genome to synthesize new functional materials. Thus, tuning of the ground state of superlattices is crucial to further control their physical properties. In this study, superlattices (SLs) consisting of alternating layers of SrRuO 3 (SRO) (5 nm) and La 0.5 Ca 0.5 MnO 3 (LCMO) (5 nm) are epitaxially grown on SrTiO 3 (STO) and LaAlO 3 (LAO) substrates with 10-unit-cell periods. A variation in the substrate-induced-strain for this choice of SLs triggers observation of remarkable properties, such as magnetic anisotropy and large magnetic hysteresis. The strain states experienced by LCMO and SRO in these SLs result in strong ferromagnetic interlayer coupling and weak antiferromagnetic interlayer coupling at low temperatures in SLs of LCMO-SRO/STO and a strong antiferromagnetic interlayer coupling in SLs of LCMO-SRO/LAO. Besides, a large magnetic hysteresis resulting from the predominant magnetic anisotropy of SRO together with the strength of magnetic coupling is observed in SLs of LCMO-SRO/LAO along the out-of-plane direction of the LAO substrate. These four different magnetic behaviors along four different directions of substrate orientations are interpreted in terms of preferential orbital occupation and competing magnetic exchange coupling together with magnetic anisotropy. This study demonstrates the subtleties in controlling the strength of magnetic coupling at the interface and stands as a model system to realize fascinating magnetic phenomena in layer-by-layer hetero-epitaxial oxide films., Competing Interests: The authors declare no competing financial interest.

Psoriasis is a chronic inflammatory disease. The aim of this study was to evaluate the effects of methotrexate and retinoid on risks for developing cerebrovascular disease among psoriatic patients. A population-based nested case-control study was conducted using the Taiwanese National Health Insurance database. Cox proportional hazards models were adopted. The hazard ratio (HR) of newly developed cerebrovascular disease was 1.28 (95% confidence interval (CI) = 1.162-1.413; p < 0.0001) for psoriatic vs. non-psoriatic subjects. In terms of the effects of methotrexate or retinoid on the occurrence of cerebrovascular disease, a significant protection effect (HR = 0.50; 95% CI = 0.27-0.92; p = 0.0264) was found for patients with methotrexate prescription. Retinoid prescription showed no protective effect. Further analyses revealed that a low cumulative methotrexate dose is associated with significant protective effect (HR = 0.53; 95% CI = 0.28-1.00; p = 0.0486) while a high cumulative dose was not (HR 0.80; 95% CI = 0.11-5.68; p = 0.8214). These results suggest that psoriatic patients receiving low-dose methotrexate treatment may have reduced risk for developing cerebrovascular disease. Further prospective study should be performed to validate the vasculoprotective effect of this treatment strategy.