Survival of a sars-cov-2 surrogate on flow-pack polyethylene and polystyrene food trays at refrigeration and room temperature conditions

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of the current pandemic referred to as coronavirus disease 2019, is spread by direct and indirect transmission between humans, including contact with contaminated surfaces, frozen food, packaging materials, and storage environments. Food contamination may occur in the “farm-to-table” lifecycle through contact with food handlers and environments. In the present study, the survival of a SARS-CoV-2 surrogate (feline coronavirus (FCoV)) at room temperature and refrigeration conditions for different time intervals on two types packaging widely used packaging, namely flow-pack polyethylene and polystyrene food trays, was investigated. FCoV was stable on the flow-pack polyethylene for 48 h and 120 h at room temperature and 4◦C, respectively, while it persisted on polystyrene food trays for 36 h at room temperature and for 120 h at +4◦C. The results of our study highlight the possible implications of food packaging in the spread of SARS-CoV-2 during the current pandemic

Pressure dependence of the refractive index of monoclinic and yttria-stabilized cubic zirconia

The pressure dependence of the refractive index of monoclinic and yttria-stabilized cubic zirconia was measured up to 3 and 8 GPa, respectively, using an interferometric method with the diamond-anvil cell. The experimental results show a practically linear behavior for both crystalline structures. For cubic zirconia, the refractive index remains practically constant under pressure, while for the biaxial monoclinic phase, one component of the refractive index decreases and the other component increases with pressure, despite the rather isotropic lattice compression in the corresponding crystalline directions. The behavior of the electronic polarizability of the oxygen ion was investigated through the LorentzLorenz relation, yielding the following Mueller parameters: for the cubic phase A0= 1.02, and for the monoclinic phase A0=1.05 for the component nearly parallel to the b direction, and A0=0.85 for the component in the direction of the projection of the "a" axis on the sample plane. In the case of monoclinic zirconia, the behavior of the polarizability under pressure is about 20% more anisotropic than the compression of the respective lattice parameters, indicating a distinct effect of the interatomic interactions over the oxygen íons for the two directions under consideration

Processing of amorphous carbon films by ultrafast temperature treatment in a confined geometry

A pressure cell with an anvil made of sapphire and the other made of tungsten carbide, was constructed to process thin film samples using a high power Nd:YAG pulsed laser, in a regime of ultrafast quenching rate and confined geometry. The sapphire anvil worked as the optical window to the laser beam and also as a good thermal conductor substrate. Thin films of amorphous carbon deposited over copper substrate were processed under pressure by Nd:YAG laser pulses. This process induces the formation of a high temperature region at the sample surface during a very short time interval of the order of the 8 ns laser pulse duration. To avoid the complete evaporation of the film, an external pressure of about 0.5 to 1.0 GPa was applied, confining the sample. With the aid of the nanosecond pulsed laser, absorbed on a very thin film sample, this specially designed apparatus provides the means to produce ultrafast quenching as the formation of a plume is suppressed and heat dissipation is accelerated by the high thermal conductivity of the copper substrate and sapphire anvil. The processed samples were analyzed by microRaman spectroscopy and the results indicated the formation of polyynic carbyne structures, as revealed by the presence of a characteristic Raman peak at about 2150 cm-1. Another set of Raman peaks observed at 996, 1116, and 1498 cm-1, also appeared when the amorphous carbon film was processed with a sequence of more than three consecutive laser pulses. These peaks, whose general aspect is very similar to that of polyacethylene (CnHn), could be ascribed to the cumulenic carbyne structure, stabilized by some dispersed copper atoms

Assignment of the human cytokeratin 3 gene (KRT3) to 12q12-->q13 by FISH.

We used fluorescence in situ hybridization to localize the human gene for cytokeratin 3 (KRT3), a member of the type II subfamily of cytokeratins, within the human genome. The results show that KRT3 is located within chromosome region 12q12-->q13. All human type II keratin genes mapped to date have been assigned to chromosome 12, where they are likely to be organized into one homotypic cluster

Tuning Anatase-Rutile Phase Transition Temperature: TiO2/SiO2 Nanoparticles Applied in Dye-Sensitized Solar Cells

TiO2/SiO2 nanoparticles with 3, 5, and 10 molar percent of silica, were synthesized by hydrothermal method and characterized by SEM, TEM, N2 adsorption-desorption isotherms, X-ray diffraction, and Raman and UV-Vis spectroscopy. While pristine TiO2 thermally treated at 500°C presents a surface area of 36 m2 g-1 (±10 m2 g-1), TiO2/SiO2 containing 3, 5, and 10 molar percent of silica present surface areas of 93, 124, and 150 m2 g-1 (±10 m2 g-1), respectively. SiO2 is found to form very small amorphous domains well dispersed in the TiO2 matrix. X-ray diffraction and Raman spectroscopy data show that anatase-to-rutile phase transition temperature is delayed by the presence of SiO2, enabling single-anatase phase photoanodes for DSSCs. According to the I×V measurements, photoanodes with 3% of SiO2 result in improved efficiency, which is mainly related to increased surface area and dye loading. In addition, the results suggest a gain in photocurrent related to the passivation of defects by SiO2