ZnO films with Ti atoms incorporated (TZO) in a wide range (0-18 at. %) have been grown by reactive co-sputtering on silicon and glass substrates. The influence of the titanium incorporation in the ZnO matrix on the structural and optical characteristics of the samples has been determined by Rutherford backscattering spectroscopy (RBS), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The results indicate that the samples with low Ti content (< 4 at. %) exhibit the wurtzite-like structure, with the Ti+4 ions substitutionally incorporated into the ZnO structure, forming Ti-doped ZnO films. In particular, very low concentration of Ti (<0.9 at. %) leads to a significant increase of the crystallinity of the TZO samples. Higher Ti contents give rise to a progressive amorphization of the wurtzite-like structure so samples with high Ti content (≥18at. %), displays an amorphous structure indicating the XPS analysis a predominance of Ti-O-Zn mixed oxides. The energy gap, obtained from absorption spectrophotometry, increases from 3.2 eV for pure ZnO films to 3.6 eV for those with the highest Ti content. Ti incorporation in the ZnO samples below 0.9 at. % rises both, the blue (380 nm) and green (550 nm) bands of the photoluminescence (PL) emission, thereby indicating a significant improvement of PL efficiency of the samples.

Background: In susceptible hosts, SARS-CoV2 induced hyperinflammation accounts for an increased mortality. The search of adjuvant immunomodulatory therapies has been ongoing ever since the pandemic outbreak. Aim: Our purpose was to evaluate the efficacy of cyclosporin A (CsA) as add-on therapy to standard of care in patients with severe COVID-19 pneumonia. Methods: We conducted a randomized clinical trial in patients admitted to 8 Spanish Tertiary Hospitals. Patients were stratified into two severity categories and randomized 1:1 to receive a high dose corticosteroid-based standard therapy with or without CsA. The primary endpoint was FiO2 recovery by day 12 without relapses. Results: 109 patients were included and 98 randomized: 51 of them were assigned to CsA+SoC group and 47 to Standard of Care (SoC). 96/98 of them were included in the Intention to Treat population. 35 (68.6%) patients from CsA+SoC group and 32 (71,1%) patients from SoC group reached the primary endpoint in the ITT analysis. No differences were found after stratification into age groups, severity level at admission or the combination of both. Overall, time to FiO2 normalization was 7.4 days vs 7.9 days in the experimental and control groups, respectively. Global mortality was 8.2%. Severe adverse events were uncommon and equally distributed between arms. Conclusion: Addition of CsA did not show differences over a high-dose corticosteroids-based treatment in the clinical course of included patients. A better identification of candidates who will benefit from receiving immunomodulatory drugs is necessary in future studies.