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Abstract We report the evolution of the superconducting properties of a commercial coated conductor during deoxygenation and reoxygenation processes. By analyzing the changes on the critical temperature, T c, and critical current density, J c, at 4 and 77 K, we have identified the conditions that cause a complete deoxygenation of the coated conductor and, also, the reoxygenation conditions that allow a recovery of the superconducting properties. A complete suppression of superconductivity happens at ~ 500–550 °C under a pure argon flow. After a complete deoxygenation, we observed that a reoxygenation process at ~ 400–450 °C in pure oxygen flow allows, not only a full recovery, but even an improvement in J c, both at 4 and 77 K. Such an increase of J c is kept or even enhanced, especially at 77 K, in the presence of magnetic fields up to ~ 6 T. A microstructural analysis by transmission electron microscopy did not give evidence of major differences in the densities of Y2O3 nanoparticles and stacking faults between the pristine and reoxygenated samples, suggesting that these defects should not be the cause of the observed enhancement of J c . Therefore, the combined action of other types of defects, which could appear as a consequence of our reoxygenation process, and of a new level of oxygen doping should be responsible of the J c enhancement. The higher J c that can be achieved by using our simple reoxygenation process opens new parameter space for CCs optimization, which means choosing a proper pO2-temperature–time trajectory for optimizing J c.

Abstract To achieve a sustainable human presence on the Moon, it is critical to develop technologies utilising the local resources (a.k.a. in-situ resource utilisation or ISRU) for construction and resource extraction. In this study, we investigate the viability of microwave heating of two lunar soil simulants (JSC-1A and OPRH3N) under vacuum conditions, to simulate a lunar surface environment compared to previous studies performed at atmospheric pressure. All simulants are thermally treated in a bespoke 2.45 GHz microwave apparatus using three input powers: 1000 W, 600 W and 250 W. The microstructures and mechanical properties of the microwaved samples are analysed to identify their potential applications. Our key findings are: (i) higher input powers generate materials in shorter fabrication times with higher mechanical strengths and higher yields despite the same total energy input; (ii) the microstructures of the microwaved samples under vacuum are very different from those under atmospheric conditions due to the widespread vesicles/bubbles; and (iii) different heating rates caused by different input powers can be utilised for specific ISRU purposes: higher input powers for extra-terrestrial construction and lower input powers for resource extraction. Findings from this study have significant implications for developing a microwave-heating payload for lunar ISRU demonstration missions.

Abstract The D614G mutation in the Spike protein of the SARS-CoV-2 has effectively replaced the early pandemic-causing variant. Using pseudotyped lentivectors, we confirmed that the aspartate replacement by glycine in position 614 is markedly more infectious. Molecular modelling suggests that the G614 mutation facilitates transition towards an open state of the Spike protein. To explain the epidemiological success of D614G, we analysed the evolution of 27,086 high-quality SARS-CoV-2 genome sequences from GISAID. We observed striking coevolution of D614G with the P323L mutation in the viral polymerase. Importantly, the exclusive presence of G614 or L323 did not become epidemiologically relevant. In contrast, the combination of the two mutations gave rise to a viral G/L variant that has all but replaced the initial D/P variant. Our results suggest that the P323L mutation, located in the interface domain of the RNA-dependent RNA polymerase, is a necessary alteration that led to the epidemiological success of the present variant of SARS-CoV-2. However, we did not observe a significant correlation between reported COVID-19 mortality in different countries and the prevalence of the Wuhan versus G/L variant. Nevertheless, when comparing the speed of emergence and the ultimate predominance in individual countries, it is clear that the G/L variant displays major epidemiological supremacy over the original variant.

Abstract Folliculotropic Mycosis Fungoides (FMF) is a rare variant of Mycosis Fungoides involving the scalp leading to alopecia. The clinical and trichoscopic features in 18 patients were analyzed and compared with the reports in the literature. Gender, age, disease stage, site of onset were taken into consideration. Clinical and trichoscopic analyses were performed on each patient. From a clinical point of view, Folliculotropic Mycosis Fungoides lesions involving the scalp presented as generalized alopecia (27.8%) or patchy-plaque alopecia (72.2%). Trichoscopic analysis revealed six most frequent features: single hair (83.3%), dotted dilated vessels (77.8%), broken-dystrophic hairs (66.7%), vellus hairs (61.1%), spermatozoa-like pattern vessels (55.6%), and yellow dots (55.6%). Additional identified trichoscopic patterns were dilation of follicular openings, scales-crusts, purpuric dots, short hair with split-end, pigtail hairs, perifollicular hyperkeratosis, milky-white globules, black dots, white dots/lines and absence of follicular dots. These trichoscopic features were further correlated to clinical presentations and stage of the disease. The rarity of the disease is a limitation. The relatively high number of patients allowed to identify several clinical and trichoscopic patterns that could be featured as specific or highly suspicious for FMF in order to consider trichoscopy as a complementary diagnostic approach and improve the differential diagnoses between FMF and other scalp disorders.

Abstract For a sustainable human presence on the Moon, it is critical to develop technologies that could utilise the locally available resources (a.k.a. in situ resource utilisation or ISRU) for habitat construction. As the surface soil is one of the most widely available resources at the Moon, we have investigated the viability of microwave heating of a lunar soil simulant (JSC-1A). JSC-1A was thermally treated in a bespoke microwave apparatus using 2.45 GHz frequency, using five different microwave powers in the range of 250 W to 1000 W. The structural properties of the resulting products were analysed to determine whether their microstructures and mechanical strengths differ under different input powers; and whether input power plays a crucial role in triggering thermal runaway, for identifying the optimum power for developing a microwave-heating. Our key findings are: (i) the higher input powers (800 W and 1000 W) generate the highest yields and microstructures with the greatest mechanical strengths, at the shortest fabrication times, and (ii) thermal runaway improves the microwave heating efficiency despite the rapid increase in temperature, once it is triggered. Our findings are of key importance for developing a microwave-heating payload for future lunar ISRU demonstration missions, contributing towards 3D printing-based extra-terrestrial construction processes.