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BACKGROUND: Psychometrical evaluation of persons of diverse contexts and different populations, including general or clinical. OBJECTIVE: This review study aimed to evaluate the psychometrics quality of resilience scales. METHODS: International and Iranian databases were searched with MESH terms, including psychometric, validity, reliability, Connor-Davidson resilience scale, Resilience scale, for published articles up to 1 February 2023. For each of the selected studies, the risk of bias was evaluated using the COSMIN Risk of Bias Checklist. Then the COSMIN checklist was used to evaluate the entire text of the article for methodological quality. RESULTS: Considering the inclusion criteria, 80 documents were evaluated. According to the COSMINs criteria for evaluating the risk of bias, the current study findings revealed the included studies limitations in assessing the three versions of CD-RISC cross-cultural and content validity as well as their stability (e.g. conducting test re-test), whereas the majority of psychometric studies of CD-RISC-25, and CD-RISC-2 rated as very good or adequate in terms of structural validity. In terms of quality assessment of the included studies, the current study indicated that investigating the structural validity of the CD-RISC was mainly done based on exploratory factor analysis (EFA), and confirmatory factor analysis was absent. CONCLUSION: The general result indicates the acceptability of the quality of the studies. However, concerns for measurement properties such as responsiveness and criterion validity as well as the standard error of measurement have been neglected.

The main purpose of this study was to investigate the relationship between microstructure and mechanical performance of polylactic acid when mixed with styrene-ethylene butylene-styrene copolymer and also graphene nanoplatelets. For this purpose, a series of neat polymer blends were first prepared with varying mixing ratios through a one-step melt mixing technique. Subsequently, the effect of various loadings of graphene nanoplatelets on the best mixing ratio (optimal composition) of the binary blend was investigated. To understand the different performances of various nanocomposites, the correlation of mechanical, rheological, and microstructural properties was thoroughly investigated using X-ray diffraction, scanning electron microscopy, linear viscoelastic behavior, tensile testing, and impact strength analyses. Furthermore, the influence of the mixing sequence of nanocomposites preparation on the microstructure and mechanical performance of nanocomposites was studied. Results demonstrated that the incorporation of graphene nanoplatelets as well as mixing sequence has a substantial effect on the final properties of prepared nanocomposites which was deeply discussed. [ABSTRACT FROM AUTHOR]

In this research, the degradation of a polymer blend in the presence of nanoparticles by considering the effect of nanoparticles on the degradation was investigated using emulsion models and fractional Zener model for the first time. Poly(lactic acid)/poly(caprolactone)/zinc oxide nanocomposite blends were prepared using the melt mixing method. Interface complex shear modulus for the neat polymer blend and its nanocomposites were calculated using emulsion models in a range of frequencies. All competing factors imposing elasticity on the systems, including the solid-like behavior and degradation catalytic activity of ZnO nanoparticles in the presence of polyesters, were considered. After comparing the interface complex shear modulus of samples, it was revealed that the negative elastic impact of ZnO (degradation role) governs the viscoelastic behavior of these systems. Accordingly, the samples containing ZnO nanoparticles exhibited low elasticity, which was attributed to overcoming the degradation role of ZnO compared with the hydrodynamic interaction of ZnO nanoparticles. Additionally, the results obtained from the fractional Zener model were in good harmony with the emulsion model analysis. KEYWORDS biodegradable polymers, hydrolytic degradation, nanocomposites, viscoelastic emulsion models, ZnO nanoparticles, 1 | INTRODUCTION In recent decades, one of the causes of environmental pollution is petroleum products. Due to the widespread use of polymers, it is inevitable to replace the degradable [...]

The present study explores the effect of chitosan (CS)-assembled graphene oxide (GO) on the microstructure and mechanical properties of polycaprolactone (PCL) nanocomposites. To this end, firstly, CS-assembled GO sheets were synthesized. Subsequently, the effect of adding various amounts of GO-CS nanohybrid and GO sheets on the rheological and mechanical performance of PCL-based nanocomposites was investigated. It was observed that GO-CS nanohybrid exhibited an interesting dual role based on the amount of addition: the motion-limiting role and the lubricating role. Additionally, the tensile strength and Young's modulus of the PCL nanocomposite films containing GO-CS nanohybrid and GO sheets increased as compared to pure PCL, while its influence in terms of elongation at break was the opposite. CS assembly to conventional nanoparticles (e.g., GO) was found as an interesting approach for the simultaneous enhancement of mechanical performance and processability of polymer matrices for a vast range of applications, especially in packaging and tissue engineering. [ABSTRACT FROM AUTHOR]

The Ahmadabad hematite/barite deposit is located to the northeast of the city of Semnan, Iran. Geostructurally, this deposit lies between the Alborz and the Central Iran zones in the Semnan Subzone. Hematite-barite mineralisation occurs in the form of a vein along a local fault within Eocene volcanic host rocks. The Ahmadabad deposit has a simple mineralogy, of which hematite and barite are the main constituents, followed by pyrite and Fe-oxyhydroxides such as limonite and goethite. Based on textural relationships between the above-mentioned principal minerals, it could be deduced that there are three hydrothermal mineralisation stages in which pyrite, hematite and barite with primary open space filling textures formed under different hydrothermal conditions. Subsequently, in the supergene stage, goethite and limonite minerals with secondary replacement textures formed under oxidation surficial conditions. Microthermometric studies on barite samples show that homogenisation temperatures (TH) for primary fluid inclusions range from 142 to 256°C with a temperature peak between 200 and 220°C. Salinities vary from 3.62 to 16.70 NaCl wt% with two different peaks, including one of 6 to 8 NaCl wt% and another of 12 to 14 NaCl wt%. This indicates that two different hydrothermal waters, including basinal and sea waters, could have been involved in barite mineralisation. The geochemistry of the major and trace elements in the samples studied indicate a hydrothermal origin for hematite and barite mineralisation. Moreover, the Fe/Mn ratio (>10) and plots of hematite samples of Ahmadabad ores on Al-Fe-Mn, Fe-Mn-(Ni+Co+ Cu)×10, Fe-Mn-SiX2 and MnO/TiO2 – Fe2O3/TiO2 diagrams indicate that hematite mineralisation in the Ahmadabad deposit occurred under hydrothermal conditions. Furthermore, Ba and Sr enrichment, along with Pb, Zn, Hg, Cu and Sb depletion, in the barite samples of Ahmadabad ores are indicative of a low temperature hydrothermal origin for the deposit. A comparison of the ratios of LaN/YbN, CeN/YbN, TbN/LaN, SmN/NdN and parameters of Ce/Ce* and La/La* anomalies of the hematite, barite, host volcanic rocks and quartz latite samples to each other elucidate two important points: 1) the barite could have originated from volcanic host rocks, 2) the hematite could have originated from a quartz latite lithological unit. The chondrite normalised REE patterns of samples of hematite barite, volcanic host rocks and quartz latite imply that two different hydrothermal fluids could be proposed for hematite and barite mineralisation. The comparison between chondrite normalised REE patterns of Ahmadabad barite with oceanic origin barite and low temperature hydrothermal barite shows close similarities to the low temperature hydrothermal barite deposits.

In the present study, zinc oxide nanoparticles (ZnO-NPs) were synthesized by a hydrothermal method followed by the fabrication of polylactic acid/polycaprolactone blend (PLA/PCL, 80/20 wt/wt) at various loadings of ZnO-NPs (2, 4, and 6 wt%) via melt mixing. FTIR and XRD patterns confirmed that the ZnO-NPs were successfully synthesized. The ZnO-NPs with an average diameter of about 46–73 nm were observed by the FESEM analysis. The effect of ZnO-NPs on morphological, thermal, UV absorption, mechanical, photochemical degradation, rheological and cell viability properties of PLA/PCL blend were investigated. FESEM micrographs of bionanocomposites demonstrated that polycaprolactone was dispersed as a droplet to the Polylactic acid matrix phase. DSC analysis showed that the addition of ZnO-NPs increased the degree of crystallinity and melting temperature of the PLA. Mechanical assessment of the bionanocomposites reveals that the addition of 2, 4 and 6 wt.% of ZnO-NPs into the blend sample leads to increase in the tensile modulus by about 5.4, 11 and 24%. The MTT assay results implied that cell viability of the both filled and unfilled samples is greater than 90% indicating their biocompatibility to the fibroblast cells. It is observed that the melt linear viscoelastic properties of the prepared bionanocomposites are under control of LA/PCL chain degradation and hydrodynamic nanoparticles interaction. [ABSTRACT FROM AUTHOR]

Although zinc ions have a strong antiviral impact against viral infections, they have a high level of toxicity in cell culture and in animal models. In the current work, ZnO nanoparticles (ZnO NPs) and fibrillar chitosan‐ZnO nanostructures (CS‐ZnO NSs) were synthesized in order to evaluate their cytotoxicity and inhibitory impact against HSV (herpes simplex virus) replication in vitro using the MTT, plaque, and Real‐time PCR methods. Also, different characterization approaches such as FE‐SEM, XRD, FTIR and fluorescence microscope were used to evaluate prepared NPs. The findings revealed that CS‐ZnO NSs exhibit negligible cytotoxicity in cells, whereas ZnO NPs were exceedingly harmful at high doses. Also, CS‐ZnO NSs could considerably internalize cells and reduce virus titration in HSV‐infected cells. Furthermore, their inhibitory effect against HSV replication was quite effective, which may be more related to the antiviral activity of chitosan and ZnO. In conclusion, the new fibrillar chitosan‐ZnO NS was prepared with the least toxicity for host cells. In this study, a fibrillar chitosan‐ZnO (NF‐CS‐ZnO) nano‐hybrid is developed by antiviral activity against the Herpes simplex virus. [ABSTRACT FROM AUTHOR]