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Healthcare workers (HCWs) were at increased risk for mental health problems during the COVID-19 pandemic, with prior data suggesting women may be particularly vulnerable. Our global mental health study aimed to examine factors associated with gender differences in psychological distress and depressive symptoms among HCWs during COVID-19. Across 22 countries in South America, Europe, Asia and Africa, 32,410 HCWs participated in the COVID-19 HEalth caRe wOrkErS (HEROES) study between March 2020 and February 2021. They completed the General Health Questionnaire-12, the Patient Health Questionnaire-9 and questions about pandemic-relevant exposures. Consistently across countries, women reported elevated mental health problems compared to men. Women also reported increased COVID-19-relevant stressors, including insufficient personal protective equipment and less support from colleagues, while men reported increased contact with COVID-19 patients. At the country level, HCWs in countries with higher gender inequality reported less mental health problems. Higher COVID-19 mortality rates were associated with increased psychological distress merely among women. Our findings suggest that among HCWs, women may have been disproportionately exposed to COVID-19-relevant stressors at the individual and country level. This highlights the importance of considering gender in emergency response efforts to safeguard women’s well-being and ensure healthcare system preparedness during future public health crises.

Background The Beirut Port Blast on August 4, 2020 is the largest (non-nuclear) explosion on record. St George Hospital University Medical Center (SGHUMC), a leading academic medical centre in Lebanon, adjacent to the Port, sustained a massive loss in lives and infrastructure. Objective The current study uses the baseline data of an ongoing longitudinal study to explore the prevalence, severity, and predictors of probable Acute Stress Disorder (ASD) among health workers at SGHUMC following the blast. Methods In the context of COVID-19 tests administered 9–15 days after the blast, SGHUMC staff were asked to complete a questionnaire that included socio-demographic details, the Beirut Port Exposure Inventory, and the Acute Stress Disorder Scale (ASDS). Results A total of 570 health workers participated in the study. The prevalence of probable DSM-5 ASD [95%CI] was 38.34% [31.41; 45.32]. Many specific exposures were related, on a bivariate level, to ASD be it as a probable DSM-5 diagnosis or its severity as measured by the ASDS. A classification and regression tree (CART) analysis identified the highest risk predictors of probable DSM-5 ASD diagnosis to be: being a female, seeing dead or mutilated bodies, death of a close one, and being scared at the time of the explosion. Nurses carried the highest risks of all health workers with a probable DSM-5 ASD prevalence of 51.28%, (OR = 3.72 [95% CI: 2.22; 6.25]). Being scared at the time of the blast was the most single predictor of probable ASD. Conclusion Both the prevalence and severity of probable DSM-5 ASD in this sample are higher than most reported in the literature, which may be explained by the severity of the trauma and the ongoing stress in the context of the pandemic. Fear at the time of the explosion was independently the most predictive parameter of probable ASD. HIGHLIGHTS On 4 August 2020, 2700 tons of ammonium nitrate exploded in the port of Beirut 38.34% of all health workers and 51.2% of nurses at St Georges Hospital University Medical Center, which faces the port, had probable DSM-5 ASD in this ongoing longitudinal study

The optical properties of polyvinylidene fluoride (PVDF) polymer nanocomposite films incorporating SrTiO3/carbon nanotubes (CNTs) as nanofillers are investigated. PVDF/SrTiO3/CNTs films were prepared by the solution casting technique. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) analyses confirmed the incorporation of SrTiO3/CNTs into the PVDF matrix. The addition of nanofillers influenced the crystalline structure, morphology, and optical properties of the films. SEM images showed spherulite morphology, which is a spherical aggregate of crystalline polymer chains. The addition of a SrTiO3/CNTs nanofiller modified the polymer's electronic structure, causing a variation in the energy gap. The addition of SrTiO3/CNTs at 0.1 wt% increased the band gap, refractive index, and nonlinear optical properties of the PVDF films. These improvements indicate the potential of these nanocomposite films in optoelectronic applications such as solar cells, image sensors, and organic light-emitting diodes. [ABSTRACT FROM AUTHOR]

Water pollution by synthetic anionic dyes is one of the most critical ecological concerns and challenges. Therefore, there is an urgent need to find an efficient adsorbent and photocatalyst for dye removal. In the present study, we aimed to fabricate a hybrid mesoporous composite of spongy sphere-like SnO2 and three-dimensional (3D) cubic-like MgO (SnO2/MgO) as a promising adsorbent/photocatalyst to remove the anionic sunset yellow (SSY) dye from real wastewater at neutral pH conditions. The as-synthesized SnO2 and MgO composite was investigated using XRD, SEM, EDX, TEM, XPS, BET, and zeta potential. The experimental study of the SSY removal using SnO2/MgO composite was performed at different conditions, such as pH, stirring time, dose, and temperature. More than 99% of 10 mg/L SSY was effectively adsorbed from aqueous solution using 40 mg of SnO2/MgO composite at pH 7 and a stirring time of 60 min. The SSY adsorption behavior was well fitted by pseudo-second order and the Langmuir model, indicating that the SSY was chemisorbed to the composite-active sites as a monolayer. On the other hand, photocatalytic degradation process exhibited better results in terms of speed of removal and used quantity of photocatalyst, where 20 mg of SnO2/MgO composite can be used to remove > 99% of SSY dye within 30 min. Mechanism of SSY adsorption and photocatalytic degradation was discussed. In addition, elution experiments demonstrated that the SnO2/MgO composite as an SSY adsorbent could be reused for nine cycles without considerable reduction in the SSY adsorption efficiency. Therefore, this work exhibited that the mesoporous SnO2/MgO composite can be considered an effective adsorbent/photocatalyst to remove SSY dye from real industrial effluent water at neutral pH conditions. [ABSTRACT FROM AUTHOR]

In this research article, the investigations of how nano-zinc oxide (N-ZnO) could be changed the functional and antimicrobial features of cellulose acetate (CA) films were established. As a result, three forms of CA films comprising 0.5%, 1.0%, and 2.0% N-ZnO have been assembled. Following that, the physicochemical and barrier properties were assessed. Further, the anti-bacterial activities of prepared nanocomposite films towards Escherichia coli have been investigated using Fourier-transform infrared spectroscopy (FTIR). The obtained results demonstrated that 2.0% N-ZnO had the greatest impact on physicochemical and barrier properties. The FTIR spectra revealed that all N-ZnO concentration interactions were physical, with no chemical reactions between the nanoparticles and CA framework. The incorporation of N-ZnO improved the humidity level, water absorption, and uptake capability of CA films, which are essential factors in packaging manufacturing. The anti-bacterial effect of 2.0% N-ZnO formulation exhibited a stronger anti-bacterial impact compared to the remaining formulations. Subsequently, N-ZnO improved the overall properties of CA films and the most satisfactory concentration for utilizing N-ZnO in CA-based nanocomposite films was 2% N-ZnO. [ABSTRACT FROM AUTHOR]

In this article, we examine the effects of Sm substitution by Zn on the structures and electrochemical characteristics of SmxZn1−xFe2O4 alloys prepared by sol–gel technique. The structural properties of the electrodes are studied by X‐ray diffraction and scanning electron microscope (SEM). The structural properties of these alloy are well influenced by the substitution rate. The SEM images of the powder of all samples (x = 0, 0.2, 0.4, and 0.6) shows the presence of agglomerates in the powder particles. Moreover, EDX investigation demonstrates that the chemical and theoretical compositions of all the prepared alloys are almost the same. The electrochemical performance of the oxide electrodes was analyzed at temperature 298 K using chronopotentiometry, chronoamperometry, and cyclic voltammetry techniques. During the first cycles, the electrochemical discharge capacity increases for all alloys. Obviously, this evolution is rapid for the unsubstituted alloy, but it becomes slower by increasing the substitution rate. The highest discharge capacity value was obtained for the ZnFe2O4 electrode of the order of 180 mAh/g while the highest retained capacity was observed for the Sm0.6Zn0.4Fe2O4 electrode. The kinetic results showed that the exchange current density I0 and the hydrogen diffusion coefficient DH of the anodes increased with increasing substitution rate and the best values were obtained for the Sm0.6Zn0.4Fe2O4 anode. [ABSTRACT FROM AUTHOR]

In the recent work, the scheelite-type ABO4 compound (A = Nd and B = Os) is synthesized via a hydrothermal route directly grown on carbon cloth (NdOsO4/CC). The as-obtained electrocatalysts are analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDXS), and Brunauer–Emmett–Teller (BET) to confirm the elemental, structural, morphological, and textural properties, respectively. The scheelite-type materials can easily regulate the oxygen evolution reaction (OER) owing to the presence of oxygen vacancy and high conductivity. Therefore, the fabricated material is employed for electrochemical studies utilizing electrochemical impedance spectroscopy (EIS), CV polarization curves, linear sweep voltammetry (LSV), and chronoamperometry (CA) in an alkaline medium and responds to low overpotential of 238.0 mV and small Tafel slope of 85.0 mV dec−1 with the enduring stability of 20 h. In the current study, oxygen-deficient scheelite-type perovskites, such as ABO4, appear to represent a novel class of high-performance electrocatalyst for processes involving active oxygen intermediates, like OER and oxygen reduction reaction (ORR) in future applications. [ABSTRACT FROM AUTHOR]

Oxygen and hydrogen generated by water electrolysis may be utilized as a clean chemical fuel with high gravimetric energy density and energy conversion efficiency. The hydrogen fuel will be the alternative to traditional fossil fuels in the future, which are near to exhaustion and cause pollution. In the present study, flowery-shaped In2MnSe4 nanoelectrocatalyst is fabricated by anion exchange reaction directly grown on nickel foam (NF) in 1.0 M KOH medium for oxygen evolution reaction (OER). The physiochemical and electrical characterization techniques are used to investigate the chemical structure, morphology, and electrical properties of the In2MnSe4 material. The electrochemical result indicates that synthesized material exhibits a smaller value of Tafel slope (86 mV/dec), lower overpotential (259 mV), and high stability for 37 h with small deterioration in the current density for a long time. Hence, the fabricated material responds with an extraordinary performance for the OER process and for many other applications in the future. [ABSTRACT FROM AUTHOR]

This study aims to prepare and examine the structure, thermal and dielectric properties of Polyvinylidene fluoride (PVDF)/Polyvinylpyrrolidone (PVP)/Co0.6Zn0.4Fe2O4 nanocomposite films. The data were collected via X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and dielectric measurements. The XRD spectrum of the Co0.6Zn0.4Fe2O4 ferrite sample showed a spinel crystal structure with an average size 15 nm. In the X-ray diffraction spectra of the PVDF-Co0.6Zn0.4Fe2O4 polymer nanocomposites, β-phase diffraction peak appeared at 2θ = 0.2°. SEM images of all the nanocomposite films exhibited a homogeneous distribution of nanostructured Co0.6Zn0.4Fe2O4. FTIR spectra depicted the absorption bands for α, β and γ-phase of PVDF as well as the carbonyl group of PVP. From TGA analysis, the activation energy for thermal decomposition decreased from 285.73 to 248.97 kJ/mol.K. Besides, there is a decrease in both ΔH and ΔG values with an increase in the Co0.6Zn0.4Fe2O4 concentration. The static dielectric constant (εs), the high-frequency dielectric constant (ε∞) and the dielectric strength (Δε) for these nanocomposites were lower than the pure PVDF/PVP film. The DC conductivity values were 2.27 × 10−14, 1.63 × 10−8, 2.04 × 10−10 and 1.61 × 10−8 S/cm for 0.0, 1.0, 3.0 and 5.0 wt% of Co0.6Zn0.4Fe2O4. [ABSTRACT FROM AUTHOR]

Summary: The hydrogen storage properties of zinc ferrite spinel (ZnFe2O4) alloy were studied, in this work. This alloy, formed applying the sol‐gel technique, was employed as anode in Ni‐MH accumulators. X‐ray diffractogram analysis showed the appearance of the compound spinel with cubic structure. In fact, the crystallite size, specified by the TEM technique, was equal to 30 nm. The hydrogen storage properties of zinc ferrite spinel alloy were examined applying various electromechanical methods (chronopotentiometry, cyclic voltammetry, and chronoamperometry) at the C/10 rate and at room temperature. The maximum discharge capacity value was almost equal to 145 mAh/g. After 100 cycles, a good cycling stability was attained and correlation between the (DH/a2) ratio and the discharge capacity as noticed. The electrolyte/ZnFe2O4 anode interface prior to and following activation was studied utilizing electrochemical impedance spectroscopy. [ABSTRACT FROM AUTHOR]