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Hardness of thin films is a noteworthy property in the electronic and mechanical industry and is generally observed to be dependent on the degree of roughening facilitated from surface heights' surface spatial heterogeneity at the mesoscopic observation scale. Nonetheless, owing to enhanced scale fluctuations and higher-order central moments, conventional parameters provide limitations and errors in capturing the spatial heterogeneity of surfaces. Herein, we have utilized scale-independent fractal parameters to analyze the spatial heterogeneity of surface heights in Ti1−xSixN ternary hard films deposited with varying Si doping concentrations using sputtering technique. The fractal dimension, lacunarity coefficient, Moran index, surface entropy, Otsu's separability, and fractal succolarity were computed to provide an overarching understanding of the surface heights' spatial heterogeneity. Principal component analysis was employed on the data sets to identify the parameter(s) accounting for the maximum variance and accordingly, the structure–property relation between spatial heterogeneity of surface and hardness is analyzed and discussed in the context of the fractal dimension of surface heights. The results indicate the possibility of mesoscopic surface engineering and, consequently, tuning of hardness and modulus of elasticity in Ti1−xSixN hard films by mere changing of surface spatial heterogeneity facilitated by the fractal dimension of surface heights. [ABSTRACT FROM AUTHOR]

Reverse transcription-quantitative PCR (RT-qPCR)-based assays are extensively being utilized to detect coronavirus disease 2019 (COVID-19). However, due to a lack of RT-qPCR testing capability, these tests cannot be carried out in community clinics. The intention of our study was to evaluate the specificity and sensitivity of Rapid Antigen Detection (RAT) tests versus those of RT-qPCR using nasopharyngeal and oropharyngeal specimens. Respiratory swab specimens were collected from the COVID-19 patients admitted at Dr. Bhimrao Ambedkar Memorial Hospital, Raipur, CG, India, during March to April 2022. RAT and RT-qPCR were performed using standard methods as per guidebook instructions, and subjects were chosen using a convenience sample technique. 100 swabs from patients, who had earlier verified positive and 100 from who had earlier verified negative for SARS-CoV-2 via RT-qPCR, were taken for study. Study was approved by the institutional ethical committee before data collection and initiation of the study. We evaluated for the sensitivity and specificity of the STANDARD Q COVID-19 Ag test kit (SD Biosensor). On testing, an over-all sensitivity and specificity of the kit was recorded as 74% and 100%, respectively in comparison to the RT-qPCR kit. Further, the assay's sensitivity was shown to be 100%, 94.87%, 77.27%, and 55.56%, respectively, for samples with cycle thresholds (Ct) of 15-25, 25-30, 30- 35, and >35. We draw the conclusion that the RT-qPCR assay has superior sensitivity and specificity to the antigen assay. However, in all situations where RT-qPCR testing is difficult, the antigen assay could serve as a rapid and simple option for separating SARS-CoV-2 contagious from non-contagious patients. [ABSTRACT FROM AUTHOR]

Efficient sarcolemmal repair is required for muscle cell survival, with deficits in this process leading to muscle degeneration. Lack of the sarcolemmal protein dysferlin impairs sarcolemmal repair by reducing secretion of the enzyme acid sphingomyelinase (ASM), and causes limb girdle muscular dystrophy 2B (LGMD2B). The large size of the dysferlin gene poses a challenge for LGMD2B gene therapy efforts aimed at restoring dysferlin expression in skeletal muscle fibers. Here, we present an alternative gene therapy approach targeting reduced ASM secretion, the consequence of dysferlin deficit. We showed that the bulk endocytic ability is compromised in LGMD2B patient cells, which was addressed by extracellularly treating cells with ASM. Expression of secreted human ASM (hASM) using a liver-specific adeno-associated virus (AAV) vector restored membrane repair capacity of patient cells to healthy levels. A single in vivo dose of hASM-AAV in the LGMD2B mouse model restored myofiber repair capacity, enabling efficient recovery of myofibers from focal or lengthening contraction-induced injury. hASM-AAV treatment was safe, attenuated fibro-fatty muscle degeneration, increased myofiber size, and restored muscle strength, similar to dysferlin gene therapy. These findings elucidate the role of ASM in dysferlin-mediated plasma membrane repair and to our knowledge offer the first non-muscle-targeted gene therapy for LGMD2B., Introduction Skeletal muscle cells (myofibers) enable physical movement and are frequently damaged by strenuous activity, overload, and eccentric contractions (1, 2). Mutations that increase myofiber fragility or impede repair result [...]

Cells are routinely exposed to agents that cause plasma membrane (PM) injury. While pore‐forming toxins (PFTs), and chemicals cause nanoscale holes dispersed throughout the PM, mechanical trauma causes focal lesions in the PM. To examine if these distinct injuries share common repair mechanism, membrane trafficking is monitored as the PM repairs from such injuries. During the course of repair, dispersed PM injury by the PFT Streptolysin O activates endocytosis, while focal mechanical injury to the PM inhibits endocytosis. Consequently, acute block of endocytosis prevents repair of diffuse, but not of focal injury. In contrast, a chronic block in endocytosis depletes cells of early endosomes and inhibits repair of focal injury. This study finds that both focal and diffuse PM injury activate Ca2+‐triggered exocytosis of early endosomes. The use of markers including endocytosed cargo, Rab5, Rab11, and VAMP3, all reveal injury‐triggered exocytosis of early endosomes. Inhibiting Rab5 prevents injury‐triggered early endosome exocytosis and phenocopies the failed PM repair of cells chronically depleted of early endosomes. These results identify early endosomes as a Ca2+‐regulated exocytic compartment, and uncover the requirement of their dual functions – endocytosis and regulated exocytosis, to differentially support PM repair based on the nature of the injury. [ABSTRACT FROM AUTHOR]

The anatase phase of TiO2 is highly suitable for photocatalytic application consequently, prerequisite an unpretentious scale‐independent understanding of its roughening‐facilitated surface topography dynamics. Herein, the nonlinear roughening in anatase thin films and its correlation with the nonlinear trend of optical properties in the framework of fractal geometry are investigated. The self‐affine nature of analyzed surfaces is confirmed from the autocorrelation function. The dynamic scaling exponents indicate the existence of Kardar–Parisi–Zhang scaling in surface growth. In addition, the trend of generalized Hurst exponent and mass exponent indicates insignificant multifractal characteristics in the analyzed surfaces. Moreover, fractal analysis explains and aids to description of roughening trend from stereometric and Minkowski functionals analysis. Furthermore, the significance of fractal dimension for probing the surface roughening is validated from the principal component analysis. Consequently, variation in optical bandgap and linear refractive index are investigated in regards to the fractal dimension and root mean‐squared surface slope and regression equations are proposed for tuning of bandgap. [ABSTRACT FROM AUTHOR]

In this article, we have studied the detailed electrical and optical characteristics of crystalline α-, γ-, and α + γ-manganese sulfide (MnS) thin films. Highly ordered thin films of α-, γ-, and α + γ-MnS were prepared by direct current reactive sputtering on glass substrates at different substrate temperatures (room temperature to 400 °C) while maintaining other parameters at optimized values. The X-ray diffraction measurement revealed the synthesis of γ-, α + γ-, and α-phase of MnS thin films with preferred orientations (002), (002) + (200), and (200), respectively. The morphological and topographical results demonstrated that the particle size as well as the average roughness of MnS samples varied as a linear function of the substrate temperature. The x-ray photoelectron spectroscopy study revealed that the γ-MnS sample prepared at room temperature has the lowest oxygen related vacancy (12.7%). The optical characteristics such as refractive index n, extinction coefficient k, and optical bandgap Eg are determined in the broad wavelength range of 246–688 nm using spectroscopic ellipsometry. Moreover, the nonlinear refractive index n2 and the third-order nonlinear optical susceptibility χ(3) are determined using the Tichy–Ticha relation and Wemple–Didomenico parameters. The ratio of the carrier concentration to the effective mass N/m* has also been determined, indicating best electrical properties for γ-MnS films. The current research on the optical and electrical properties of highly ordered α-, γ-, and α + γ-MnS thin films is expected to have a significant impact on advanced optoelectronic, photonic, and energy applications. [ABSTRACT FROM AUTHOR]

Ultraviolet (UV) radiation reaching the Earth's surface is a major societal concern, and therefore, there is a significant consumer demand for cosmetics formulated to mitigate the harmful effects of UV radiation. Synthetic sunscreens being formulated to block UV penetration include inorganic metal oxide particles and organic filters. Lately, organic UV-absorbing compounds are manufactured from non-renewable petrochemicals and, as a result, there is a need to develop a sustainable manufacturing process for efficient, high-level production of a naturally occurring group of UV-absorbing compounds, namely mycosporine-like amino acids (MAAs), for use as a sunscreen additive to skincare products. Currently, the commercial production of MAAs for use in sunscreens is not a viable proposition due to the low yield and the lack of fermentation technology associated with native MAA-producing organisms. This review summarizes the biochemical properties of MAAs, the biosynthetic gene clusters and transcriptional regulations, the associated carbon-flux-driving processes, and the host selection and biosynthetic strategies, with the aim to expand our understanding on engineering suitable cyanobacteria for cost-effective production of natural sunscreens in future practices. [ABSTRACT FROM AUTHOR]

Ultraviolet radiation (UVR) has been scientifically proven to cause skin disorders such as sunburn, skin cancer and the symptoms of chronic exposure. Natural sun screening compounds have recently gained tremendous attention from the cosmetic and cosmeceutical sectors for treating skin disorders such as hyperpigmentation and aging. A wide range of natural UV-absorbing compounds have been used to replace or reduce the number of synthetic sunscreen molecules. One of the primary causes of photoaging is DNA damage, mainly caused by UVR. Photoprotection provided by traditional sunscreens is purely preventative and has no efficacy after DNA damage has been initiated. As a result, the quest for DNA-repair mechanisms that block, reverse, or postpone pathologic processes in UV-exposed skin has stimulated anti-photoaging research and methods to increase the effectiveness of traditional sunscreens. This review summarizes many natural compounds from microalgae, lichens, and plants that have demonstrated potential photoprotection effects against UV radiation-induced skin damage. Furthermore, it offers an overview of current breakthroughs in DNA-repair enzymes utilized in sunscreens and their influence on photoaging. [ABSTRACT FROM AUTHOR]