Aim: We aimed to investigate the potential inhibitory effects of diterpenes on SARS-CoV-2 main

protease (Mpro). Materials & methods: We performed a virtual screening of diterpenoids against Mpro

using molecular docking, molecular dynamics simulation and absorption, distribution, metabolism and

excretion) analysis. Results: Some tested compounds followed Lipinski’s rule and showed drug-like

properties. Some diterpenoids possessed remarkable binding affinities with SARS-CoV-2 Mpro and

drug-like pharmacokinetic properties. Three derivatives exhibited structural deviations lower than 1 A˚ .

Conclusion: The findings of the study suggest that some of the diterpenes could be candidates as potential

inhibitors for Mpro of SARS-CoV-2.

The pure conjugated polyarylene azomethine (CPAA) and its nanocomposites (CPAA-TiO₂) with different concentrations of TiO₂ nanoparticles were successfully prepared by in-situ technique and analyzed by different advanced techniques. XRD has confirmed the structural properties and crystallinity of (CPAA) and nanocomposites. The SEM clearly shows that the (CPAA) is uniform and homogeneous, with tightly connected aggregate layers in shape. However, the amount of TiO₂ in the nanocomposites greatly affects their morphology, revealing structural differences and indicating a reaction between (CPAA) and TiO₂, especially at a higher concentration of 5% TiO₂. A new composite of (CPAA) was introduced and the photocatalytic effect for MB was studied. The removal efficiency of (pure-CPAA) over MB dye under simulated sunlight was 62%. However, (CPAA-TiO₂ 1%) destroyed 90% of MB dyes. It was …

Polybenzoxazines are a class of luminescent polymers that exhibit light emission properties, making them suitable for various applications. This manuscript presents the synthesis, characterization, and thermal behavior of a novel luminescent polybenzoxazine, named P‐BZ‐CP. The synthesis of P‐BZ‐CP involved a three‐stage process, starting with the formation of Bis‐OHOMe through the reaction of cyclopentanone and vanillin, followed by a Mannich condensation reaction with p‐toluidine to obtain the monomer M‐BZ‐CP. Thermal ring‐opening polymerization of M‐BZ‐CP at 250°C resulted in the synthesis of P‐BZ‐CP. Comprehensive characterization techniques, including NMR, FTIR, XRD, SEM, TGA, and DSC, were employed to analyze the structure and properties of both M‐BZ‐CP and P‐BZ‐CP. The thermal behavior of M‐BZ‐CP curing was investigated using DSC, highlighting the temperature‐dependent …

This study employed the ball milling process to successfully craft nanostructures of Cu-doped ZnO/SnO2 (ZOSn/Cu), which were thoroughly characterized through various methods. The X-ray diffraction (XRD) analysis revealed the presence of the Zn2SnO4 cubic spinel phase in the nanostructure samples, along with diffraction peaks corresponding to ZnO or SnO2 phases. Notably, the photocatalytic degradation performance of the structured catalysts was greatly improved compared to undoped ZOSn/Cu nanostructures, achieving MB elimination rates of 60% and 80% after 120 min of irradiation, with an overall degradation of approximately 90%. The ZOSn/Cu electrode, designed for energy storage, demonstrated superior performance, boasting a specific capacitance of 380.0 Fg−1, outperforming the pure ZOSn/Cu electrode. Its trimetallic composition of zinc, copper, and tin contributed to enhanced electrochemical properties. This electrode demonstrated excellent cyclic stability, maintaining around 90% of its capacity, along with key characteristics like corrosion resistance, high conductivity, and a wealth of active sites. These properties make it highly promising for advanced energy storage applications.

Many existing control techniques proposed in the literature tend to overlook faults and physical limitations in the systems, which significantly restricts their applicability to practical, real-world systems. Consequently, there is an urgent necessity to advance the control and synchronization of such systems in real-world scenarios, specifically when faced with the challenges posed by faults and physical limitations in their control actuators. Motivated by this, our study unveils an innovative control approach that combines a neural network-based sliding mode algorithm with fuzzy logic systems to handle nonlinear systems. This proposed controller is further enhanced with an intelligent observer that takes into account potential faults and limitations in the control actuator, and it integrates a fuzzy logic engine to regulate its operations, thus reducing system chatter and increasing its adaptability. This strategy enables the system to maintain regulation in the face of control input constraints and faults and ensures that the closed-loop system will achieve convergence within a finite-time frame. The detailed explanation of the control design confirms its finite-time stability. The robust performance of the proposed controller applied to autonomous and non-autonomous systems grappling with control input limitations and faults demonstrates its effectiveness.

Black sand along the Red Sea is often composed of volcanic minerals and heavy minerals. The Red Sea region is known for its unique geological features, and black sand beaches can be found in various areas along its shores. The study presents a comprehensive semi-quantitative chemical analysis of black sand samples collected from various locations along the red sea, revealing significant variations in their elemental compositions. The main oxides were identified in each sample, determined through X-ray diffraction (XRD) and X-ray fluorescence (XRF) analyses, indicate diverse mineralogical compositions. The spatial distribution of minerals at each site is depicted through mapping. Additionally, Fourier-transform infrared (FTIR) spectra offer information on the functional groups present in the samples, revealing the existence of hydroxyl groups, aliphatic compounds, and adsorbed water molecules. For Qusier …

In Egypt, while many studies have focused on the radiometry and mineralogy of black sands, research on their effects on nearby aquatic organisms is rare. This study aimed to assess the combined effects of heat stress (HS) and black sand nanoparticles (BS-NPs) on renal function, antioxidant responses (TAC, SOD, CAT), neuro-stress indicators (AchE, cortisol), and to conduct histopathological investigations in the kidney and spleen tissues of African catfish Clarias gariepinus over a 15-day period to exposure to control, HS (32 °C), BS (6.4 g/kg diet) and HS + BS groups. The outcomes revealed that thermal stress alone showed no significant difference from the control. However, creatinine and uric acid levels were significantly higher in the BS-NPs and HS + BS-NPs groups (p < 0.001). Antioxidant markers (TAC, SOD, and CAT) were substantially reduced across all treated groups (0.05 ≥ p < 0.0001 …

The water flea, Daphnia magna, serves as a key model organism for investigating the response of aquatic organisms to environmental stressors, including hypoxia. Hypoxia-inducible factor 1-alpha (HIF-1α) is a central regulatory protein involved in the cellular response to hypoxic conditions. In this study, we used CRISPR/Cas9 gene editing to create D. magna mutant lines with targeted alterations in the HIF-1α gene. Mutants demonstrated decreased survival and reproductive output and down-regulated genes for the HIF-1α–mediated pathway in low-oxygen conditions. These findings suggest that the HIF-1α pathway is a critical component of resistance to hypoxia in D. magna. This study provides novel insights into the molecular basis of hypoxia tolerance of HIF-1α in D. magna and expands our understanding of how aquatic organisms can adapt to or be challenged by changing oxygen levels in the face of global …