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Dye-sensitized solid-state solar cells (DSSC) based on n-type and p-type have been fabricated with highest recorded power conversion efficiency. The working electrode of the cell is composed of D149 dye-coated -based interconnected nanoparticulate (20 nm) mesoporous layer with -based dense layer which was prepared on fluorine-doped tin oxide (FTO) glass substrates. deposition was carried out according to the previously reported procedure which ensures enhanced p-type conductivity of . The surface morphologies of the dense layer, porous layer and layer have been visualized using scanning electron microscopy (SEM). The cells were fabricated with the configuration of FTO/ dense layer/ porous layer/D149/CuSCN/Graphite/Cr-coated FTO. Then the cells were characterized using I-V data as functions of the dense layer resistance (which is proportional to the thickness of the dense layer) and the porous layer thicknesses. The optimum dense layer is found to have 1500 Ω/□ sheet resistance. The cell with porous layer thickness of 9 μm at this dense layer resistance shows the maximum power conversion efficiency of 2.28%. The solar cell parameters of this optimized cell are an open circuit voltage of 0.55 V, a fill factor of 0.51 and a short-circuit current density of 8.2 mA cm-2. [ABSTRACT FROM AUTHOR]

The surface modification of a TiO2 electrode with diethyldithiocarbamate (DEDTC) in dye-sensitized solar cells (DSSCs) was studied. Results from X-ray photoelectron spectroscopy (XPS) indicate that over half of the sulfur atoms become positively charged after the DEDTC treatment of the TiO2 surface. DSSCs were fabricated with TiO2 electrodes modified by adsorbing DEDTC using a simple dip-coating process. The conversion efficiency of the DSSCs has been optimized to 6.6% through the enhancement of the short-circuit current density (JSC = 12.74 mA/cm2). This is substantially higher compared to the efficiency of 5.9% (JSC = 11.26 mA/cm2) for the DSSCs made with untreated TiO2 electrodes. [ABSTRACT FROM AUTHOR]

Objectives: Studies reviewing orofacial mycoses in coronavirus disease-2019 (COVID-19) caused by severe acute respiratory syndrome 2 (SARS-CoV-2) infection are sparse. Here we review the major oral and maxillofacial mycoses of COVID-19, the associated comorbidities, and the probable precipitating factors., Methods: English-language manuscripts published between March 2020 and October 2021 were searched using PubMed, OVID, SCOPUS, and Web of Science databases, using appropriate keywords., Results: We identified 30 articles across 14 countries, which met the inclusion criteria of PRISMA guidelines. These yielded a total of 292 patients with laboratory-confirmed COVID-19, 51.4% (n = 150) of whom presented with oral and maxillofacial fungal infections, mainly comprising candidosis, mucormycosis, and aspergillosis. Candida infections were the most prevalent, present in 64% (n = 96), followed by mucormycosis, and only a single case of aspergillosis was noted. Oral and maxillofacial mycoses were predominantly seen in those with comorbidities, especially in those with diabetes (52.4%). Oral mucormycosis was noted in 8.6% (n = 13) and mainly manifested on the hard palate. An overall event rate of oral/maxillofacial mucormycosis manifestation in patients with COVID-19 with diabetes mellitus type 1/2 was about 94% (49/52; 95% confidence interval, 0.73%-0.89%), implying a very high association between diabetes mellitus and the latter condition. All fungal infections appeared either concurrently with COVID-19 symptoms or during the immediate recovery period., Conclusions: SARS-CoV-2 infection-related immunosuppression, steroid therapy, as well as comorbidities such as diabetic hyperglycemia appear to be the major predisposing factors for the onset of oral and maxillofacial mycoses in patients with COVID-19 across all age groups., Competing Interests: Conflict of interest None disclosed., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

In this work we have designed and developed a low cost and simple instrument to purify air in an enclosure. The device sucks up the air in the enclosed area, kills the microorganisms and let clean air flow out. A combination of an ultra violet light and an electric field are used to kill the microorganisms in air. Three electric field chambers (radial, parallel, perpendicular) are used to clean air more effectively. Stainless steel meshes were used to increase the density of the electric fields. The outer covers were made with plastic and wood. The instrument was tested against an evaporated bacterial solution (Staphylococcus aureus) by letting it flow through the instrument and measuring the bacterial concentration of the output air. The results showed the instrument is extremely effective even when tested against high bacterial concentrations. The instrument is extremely useful to clean air in closed rooms such as in hospitals, schools, etc. and prevent the spread of airborne diseases., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Author(s).)