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Abstract This theoretical work focuses on the application of Tamm resonance-based biosensing using a one-dimensional photonic crystal for detecting skin vitiligo, a condition caused by the loss of pigment in the body. This biosensor utilizes the interaction of light with the photonic structure to identify the specific biomarkers associated with vitiligo. The proposed structure is composed of prism/Ag/skin-sample/(GaP/PS)N/glass. The MATLAB simulations are used to obtain numerical results pertaining to the work by using the transfer matrix method (TMM). The analysis of transmission spectra of the proposed structure shows its minute sensing ability of detecting skin vitiligo. The proposed sensor possesses a higher sensitivity of 1200 nm/RIU which is higher than the sensitivities of the sensor reported earlier. Moreover, the suggested biosensor possesses an extremely high-quality factor value of 40,650 with an exceptionally small full-width-half-maximum value of 0.04 nm.

Nickel-iron-based spinel oxide was prepared and supported on multi-walled carbon nanotubes to enhance the electrochemical oxidation of ethylene glycol in an alkaline medium. NiFe2O4 was prepared using facile sol-gel techniques. Then the prepared material was characterized using different bulk and surface techniques like powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and transmitted electron microscope (TEM). Different electrodes of NiFe2O4/CNT ratios were prepared to find out the optimum spinel oxide/CNT ratio. The activity of the metal spinel oxides composite was characterized toward ethylene glycol conversion by different electrochemical techniques like cyclic voltammetry (CV), Chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). The modified electrode reached an oxidation current of 43 mA cm−2 in a solution of 1.0 M ethylene glycol and 1.0 M NaOH. Furthermore, some kinetics parameters (like diffusion coefficient, and rate constant) were calculated to evaluate the catalytic performance. Additionally, the electrode showed extreme stability for long-term ethylene glycol oxidation.

Background: Maternal diabetes mellitus (MDM) is associated with increased risks for adverse neonatal outcomes. However, the impact of MDM on neonatal outcomes in Bisha, a city in Saudi Arabia, is not well documented. This study aims to investigate the impact of MDM on neonatal outcomes in the Maternity and Children’s Hospital (MCH), Bisha, Saudi Arabia. Methods: A retrospective cohort study was conducted on 181 pregnant women with diabetes and their neonates who were diagnosed at the Maternity and Children’s Hospital (MCH), Bisha, Saudi Arabia, between 5 October 2020 and 5 November 2022. The primary outcome was a composite of adverse neonatal outcomes, including stillbirth, neonatal death, macrosomia, preterm birth, respiratory distress syndrome, hypoglycemia, and congenital anomalies. Logistic regression analyses were used to adjust for potential confounders. Results: The total sample size was 181. The average age of patients was 34 years (SD = 6.45). The majority of the patients were diagnosed with GDM, 147 (81.2%), and pre-GDM, 34 (18.8%). Neonates born to mothers with MDM had a higher risk of adverse neonatal outcomes compared to those born to mothers without MDM (adjusted odds ratio [aOR] = 1.46, 95% confidence interval [CI]: 1.25–1.70). The risks of macrosomia (aOR = 1.74, 95% CI: 1.38–2.19), LBW (aOR = 1.32, 95% CI: 1.06–1.66), and RDS (aOR = 1.57, 95% CI: 1.28–1.93) were significantly higher among neonates born to mothers with MDM. The types of DM were statistically significant in terms of their correlation with the following neonatal outcomes: hypoglycemia (p-value = 0.017), macrosomia (p-value = 0.050), and neonatal death (p-value = 0.017). Conclusions: MDM is associated with an increased risk of adverse neonatal outcomes in Bisha. The early identification and management of MDM may improve neonatal outcomes and reduce the burden of neonatal morbidity and mortality in this population.

This theoretical work focuses on the application of Tamm resonance-based biosensing using a one-dimensional photonic crystal for detecting skin vitiligo, a condition caused by the loss of pigment in the body. This biosensor utilizes the interaction of light with the photonic structure to identify the specific biomarkers associated with vitiligo. The proposed structure is composed of prism/Ag/skin-sample/(GaP/PS)N/glass. The MATLAB simulations are used to obtain numerical results pertaining to the work by using the transfer matrix method (TMM). The analysis of transmission spectra of the proposed structure shows its minute sensing ability of detecting skin vitiligo. The proposed sensor possesses a higher sensitivity of 1200 nm/RIU which is higher than the sensitivities of the sensor reported earlier. Moreover, the suggested biosensor possesses an extremely high-quality factor value of 40,650 with an exceptionally small full-width-half-maximum value of 0.04 nm. [ABSTRACT FROM AUTHOR]

Over the past few years, more studies have been conducted on the use of photonic crystals (PCs) in the detection field. Particularly fascinating for use as gas sensors are these materials' outstanding spectrum sensitivity and small design. Using one-dimensional PCs as the theoretical foundation, this work aims to develop and analyze a nanoscale system that can identify the concentration of gases in ambient air and differentiate it from contaminated air. The intended structure is composed of layers of gallium nitride (GaN) and aluminum nitride (AlN) that alternate. In between these layers is a defective layer cavity that is filled with polluted air, which has a refractive index that is quite similar to pure air. The transfer matrix method (TMM) was used to perform numerical results for the proposed sensor. This sensor achieves average sensitivity of 1791 nm/RIU, average quality factor and figure of merit (FoM) of 1833 and 2287, respectively. We therefore think that the suggested detector's design offers a strong candidate for accurate and efficient detection. Recent research on photonic crystals (PCs) for gas detection emphasizes their sensitivity and compact design. This study introduces a nanoscale sensor with GaN and AlN layers and a cavity filled with polluted air. Simulations show high sensitivity, suggesting the sensor is a promising tool for efficient gas detection. [ABSTRACT FROM AUTHOR]

Double perovskites present promising opportunities for harnessing energy from both sunlight and wasted heat. In this study, we conducted a comprehensive theoretical analysis to evaluate the mechanical, electronic, optical, and transport properties of K2LiTlX6 (X = Cl, Br, I) employing the WEIN2K code. The optimized FCC unit cell's lattice parameters exhibited an increase from 10.34 to 11.98Å when substituting Cl with Br/I. To ascertain thermodynamic and structural stability, we computed the enthalpy of formation (-2.64 to -1.89 eV) and the tolerance factor (0.97 − 0.93). The results provide evidence for the thermodynamic and structural stability of the compounds. Mechanical parameter calculations, comprising bulk, Young, and shear moduli, along with Poisson's ratio in three dimensions, reveal their anisotropic nature, with greater significance observed in K2LiTlBr6 and K2LiTlI6. Moreover, the numerical values of Poisson and Pugh ratios indicated their ductile characteristics. The materials also exhibit noteworthy properties such as hardness, ultra-low lattice thermal conductivities, and greater melting and Debye temperatures, enhancing their potential applications. The direct bandgap values underwent a transformation from the visible to the infrared region (2.57 − 0.14 eV) as the halogen size increased. Using the BoltzTraP code, we calculated temperature-dependent thermodynamic parameters, showing high electrical conductivity related to thermal conductivity. The combination of a higher Seebeck coefficient and ZT highlighted the appropriateness of these compounds for future energy harvesting applications. [ABSTRACT FROM AUTHOR]

Herein, the structural, mechanical, optoelectronic, and transport properties of double perovskites A2ScCuCl6 (A = K, Rb, and Cs) have been determined through simulations using density functional theory. The stability of K2ScCuCl6, Rb2ScCuCl6, and Cs2ScCuCl6 compounds is supported by the optimization of structural configuration and estimation of negative formation energy. The mechanical parameters are computed to quantify mechanical strength, stability, and anisotropy. The compounds that were investigated exhibit semiconductor properties, with an indirect bandgap of 1.55, 1.43, and 1.30 eV using TB-mBJ potential, respectively. The density of states also reveals the band gap and semiconductor properties of the materials. The optical characteristics of the materials have been analyzed in terms of the dielectric function, absorption, reflectance, and optical loss. The projected low excitons binding energy, high absorbance in visible and ultraviolet regions, minimal reflectivity, and energy loss suggest that these materials are highly recommended for utilization in solar energy technology. We examined the transport characteristics that vary with temperature. The combination of high electrical conductivity, moderate thermal conductivity, and higher ZT values of 0.81, 0.86, and 0.77 makes them promising candidates for thermoelectric applications. This analysis ensures that these materials can be utilized in energy conversion applications. [ABSTRACT FROM AUTHOR]

The rare earth-based perovskite oxides are vastly studied for optoelectronic and photovoltaic applications. Here in this manuscript, the structural, mechanical, thermodynamic, electronic, and optical properties of AcXO3 (X = Al, Ga, In) are addressed by density functional theory (DFT) based WIEN2k code. The optimized parameters are reported from the Birch–Murnaghan equation of states in terms of lattice constant and bulk modulus. The elastic constants C11, C12, and C44 for the cubic phase satisfy the Born–Huang stability conditions. The Poisson and Pugh's ratios discriminate that the Ac(Al/Ga)O3 have brittle and AcInO3 ductile nature. The thermodynamic parameters like melting temperature, Debye temperature, and lattice thermal conductivity have also been explained in terms of elastic constants and moduli. The electronic behavior is explained by the band structures and density of states which is mainly contributed by Ac-d, X-p, and O-p states. The replacement of Al with Ga, and In reduces the bandgap from 4.1 to 2.2 eV. The optical characteristics are studied in terms of dielectric constants, absorption coefficient, reflection, refractive index, optical loss, and their dependent parameters. The absorption region shifts from ultraviolet to the visible region making them significant for diverse optoelectronic applications. [ABSTRACT FROM AUTHOR]