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This study deals with the use of remote sensing (RS), geographic information systems (GISs), hydrologic modeling (water modeling system, WMS), and hydraulic modeling (Hydrologic Engineering Center River Analysis System, HEC-RAS) to evaluate the impact of flash flood hazards on the sustainable urban development of Tabuk City, Kingdom of Saudi Arabia (KSA). Determining the impact of flood hazards on the urban area and developing alternatives for protection and prevention measures were the main aims of this work. Tabuk City is exposed to frequent flash flooding due to its location along the outlets of five major wadis. These wadis frequently carry flash floods, seriously impacting the urban areas of the city. WMS and HEC-HMS models and RS data were used to determine the paths and morphological characteristics of the wadis, the hydrographic flow of different drainage basins, flow rates and volumes, and the expansion of agricultural and urban areas from 1998 to 2018. Finally, hydraulic modeling of the HEC-RAS program was applied to delineate the urban areas that could be inundated with floodwater. Ultimately, the most suitable remedial measures are proposed to protect the future sustainable urban development of Tabuk City from flood hazards. This approach is rarely used in the KSA. We propose a novel method that could help decision-makers and planners in determining inundated flood zones before planning future urban and agricultural development in the KSA.

Numerous works have been reported in order to enhance the barrier properties of the polystyrene (PS). In this work, hydrophilic graphene oxide (GO), prepared by the Hummer method, was surface-grafted with hydrophobic poly(4-vinylbenzyl chloride), p(VBC), via in situ radical polymerization approach. The graphene oxide/poly(4-vinylbenzyl chloride), GP(VBC), was then dispersed in the polystyrene matrix in order to obtain nano-composite thin films of different filler ratios (5, 10, 15, 20, and 25) wt%. The modified GO and its corresponding films were characterized by X-ray diffraction, Fourier transform infrared, transmission electron microscope, field emission scanning electron microscope, thermal gravimetric analysis, and contact angle. Mechanical properties of the films were studied as well. The results indicated that the surface modification step improved the dispersion of GO within the polystyrene film due to the hydrophobic nature of modified GO. Consequently, an obvious enhancement of thermal stability and mechanical properties of the PS films loaded with GP(VBC) compared with the pure films was noticed. The rate of water vapor permeability showed an abrupt decrease even at the lowest loading percentage of the filler, which is 5 wt%. The antimicrobial activity of the fabricated polystyrene nano-composite films was also investigated against deleterious pathogens. As a net result, the composite films revealed superior properties thanks to the inclusion of the GP(VBC). This present work paves the way for the next generation of high barrier and bactericide polystyrene packaging with an economic impact.

Bladder cancer is the tenth most common cancer worldwide, where its burden remains a challenge and needs new novel therapies. Several reports indicate expression of CYP4Z1 and CYP1B1 in many tumours. Their expressions are associated with a poor prognosis, and therefore proposed as promising biomarkers or targets for anticancer therapy. By using immunohistochemistry, expression of CYP4Z1 and CYP1B1 was evaluated in a panel of different types of bladder cancer, and the enzymes’ relation to histopathological features were assessed. Results showed an increased expression of CYP4Z1 (54.3%) and CYP1B1 (76.9%) in the majority of bladder cancers compared to weak or lack of expression of both enzymes in normal tissues. CYP4Z1expression was significantly associated with tumour grade and stage where the expression was markedly increased in a high grade and advanced stage of the disease ( p  < 0.05). Additionally, CYP1B1 expression was also associated with TNM staging ( p  < 0.05) and its expression was increased in patients with lymph node metastasis. The expression profiles of CYP4Z1 and CYP1B1 suggest that both enzymes have the potential to be biomarkers or targets for novel anticancer therapy for bladder cancer. Nevertheless, further studies are needed to better delineate whether these enzymes are druggable targets.

Mountain areas in the southern western corner of the Kingdom of Saudi Arabia frequently suffer from various types of landslides due to rain storms and anthropogenic activities. To resolve the problem related to landslides, landslide susceptibility map is important as a quick and safe mitigation measure and to help making strategic planning by identifying the most vulnerable areas. This paper summarizes findings of landslide susceptibility analysis at Al-Hasher area, Jizan, KSA, using two statistical models: frequency ratio and index of entropy models with the aid of GIS tools and remote sensing data. The landslide locations (inventory map) were identified in the study area using historical records, interpretation of high-resolution satellite images that include Geo-Eye in 2.5 m and Quickbird in 0.6m resolution, topographic maps of 1:10,000 scale, and multiple field investigations. A total of 207 landslides (80% out of 257 detected landslides) were randomly selected for model training, and the remaining 50 landslides (19%) were used for the model validation. Ten landslide conditioning factors including slope angle, slope-aspect, altitude, curvature, lithology, distance to lineaments, normalized difference vegetation index (NDVI), distance to roads, precipitation, and distance to streams, were extracted from spatial database. Using these conditioning factors and landslide locations, landslide susceptibility and weights of each factor were analyzed by using frequency ratio and index of entropy models. Our findings showed that the existing landslides of high and very high susceptibility classes cover nearly 80.4% and 79.1% of the susceptibility maps produced by frequency ratio and index of entropy models respectively. For verification, receiver operating characteristic (ROC) curves were drawn and the areas under the curve (AUC) were calculated for success and prediction rates. For success rate the results revealed that for the index of entropy model (AUC = 77.9%) is slightly lower than frequency ratio model (AUC = 78.8%). For the prediction rate, it was found that the index of entropy model (AUC = 74.9%) is slightly lower than the frequency ratio model (AUC = 76.7%). The landslide susceptibility maps produced from this study could help decision makers, planners, engineers, and urban areas developers to make suitable decisions.

Animal glue stains are commonly found in manuscripts, and their removal is a delicate process that requires selective treatment to avoid damaging the fragile cellulose fibers. Therefore, this study developed a novel hybrid double network hydrogel (HDNH) consisting of synthetic polymer (Polyacrylamide), natural polymers (Agarose or sodium alginate), and Zinc Oxide nanoparticles (ZnONPs) for removing animal glue stains from paper manuscripts. The cleaning mechanism relies on the capillary HDNH to draw the aged animal glue into the gel matrix. To establish the suitability of this HDNH as a paper-cleaning material, the gels were first characterized physicochemically and microstructurally, and the HDNH formulation was confirmed. At the same time, mechanical, physicochemical, morphological, optical, and wettability techniques were performed on the paper samples under investigation, both before and after the cleaning treatment, to evaluate the HDNHs’ cleaning capabilities. The results show that the Polyacrylamide/Agarose/ZnONPs (HDNH/Ag/ZnONPs) provide superior performance in removing most of the accumulated glue layers while maintaining the structural and chemical integrity of the paper substrate. Agarose provides a very rigid, highly porous structure with a superior capacity to retain water, preventing the paper from becoming waterlogged. Polyacrylamide provides flexibility and mechanical durability, allowing the hydrogel to be peeled off in one piece.

Enamel prisms possess a unique microstructure, and their damage due to erosion is irreversible, making enamel restoration through non-invasive regeneration a significant challenge. This in-vitro study aimed to reconstruct the prism-like structure of enamel damaged by citric acid erosion through non-invasive biomimetic remineralization. Grape seed extract (GSE), combined with ethylenediaminetetraacetic acid (EDTA) and agarose hydrogel, was prepared via a hydrothermal technique. Additionally, a separate solution containing monoethanolamine (MEA) and potassium phosphate dibasic (K 2 HPO 4 ) was prepared. Both solutions were applied as a treatment protocol for 30 h on citric acid-eroded enamel surfaces. Three groups were compared: the control non-eroded enamel group (G0), the eroded non-treated enamel group (G1), and the treated enamel group (G2). The enamel surfaces were analyzed using atomic force microscopy (AFM), scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM-EDX), and transmission electron microscopy (TEM). Significant topographic changes were observed in the G2 group compared to the G0 and G1 groups. AFM analysis revealed the formation of a new layer on the eroded surface as revealed by the increased arithmetical mean deviation of the roughness (Sa = 255.7 ± 40.61 nm) and the smoother surface profile (Sku = 2.98 ± 0.53) of G2 compared to both G0 and G1. SEM examination showed the presence of uniform, prism-like, regenerative tissues, and EDX analysis confirmed the formation of hydroxyapatite (HAp) with a predominant calcium oxide (1.93 Ca/P molar ratio) phase on the treated enamel surface. TEM analysis indicated a crystal size of 12–15 nm. In conclusion, the application of GSE/EDTA agarose hydrogel and MEA/ K 2 HPO 4 solution successfully repaired the eroded enamel surface, generating a uniform, prism-like enamel structure by providing the necessary inorganic mineral ions and the organic protein matrix template required for biomimetic remineralization.

This study deals with the production of natural fiber plastic composites (NFPCs) to reduce environmental pollution with agricultural and plastic waste. Where the NFPCs were prepared from waste/pure polyethylene (WPE) (pure polyethylene (50%)/recycled polyethylene (50%)) and modified sunflower waste via an eco-friendly and economic biological process. The sunflower fibers (SF) were treated via whole selective fungal isolate, namely, Rhizopus oryzae (acc no. OM912662) using two different incubation conditions; submerged (Sub), and solid-state fermentation (SSF) to enhance the fibers' compatibility with WPE. The treated and untreated fibers were added to WPE with various concentrations (10 and 20 wt%). The morphology and structure of fibers were characterised by a scanning electron microscope (SEM) and attenuated total reflection-Fourier transform infrared (ATR-FTIR). Furthermore, the mechanical properties, morphology, biodegradation and water vapour transmission rate (WVTR) for the prepared NFPCs were investigated. The results showed that compatibility, mechanical properties and biodegradation of NFPCs were improved by the addition of sunflower fibers treated by SSF conditions.

Tephorosia purpurea subsp. apollinea was extracted with methanol and n-hexane to obtain sub-fractions. The chemical compounds identified with GC-MS and HPLC in T. purpurea subsp. apollinea extracts showed antioxidant and anticancer properties. The antioxidant and anticancer activities were investigated using DDPH and ABTS assays, and MTT assay, respectively. Stigmasta-5,24(28)-dien-3-ol, (3 β,24Z)-, 9,12,15-octadecatrienoic acid methyl ester, phytol, chlorogenic acid, and quercetin were the major chemical compounds detected in T. purpurea subsp. apollinea. These compounds possessed antioxidant and anticancer properties. The methanol extract showed antioxidant properties with DDPH and ABTS radical scavenging of 84% and 94%, respectively, relative to ascorbic acid and trolox. The anticancer effects of T. purpurea subsp. apollinea against the cancer cell lines MCF7 (IC50 = 102.8 ± 0.6 μg/mL), MG63 (IC50 = 118.3 ± 2.5 μg/mL), T47D (IC50 = 114.7 ± 1.0 μg/mL), HeLa (IC50 = 196.3 ± 2.3 μg/mL), and PC3 (IC50 = 117.7 ± 1.1 μg/mL) were greater than its anticancer effects against U379 (IC50 = 248.4 ± 7.5 μg/mL). However, it had no adverse effects on the normal cells (WI38) (IC50 = 242.9 ± 1.8 μg/mL). Therefore, the major active constituents presented in T. purpurea subsp. apollinea can be isolated and studied for their potential antioxidant and anticancer effects against breast, cervical, and prostate cancers and osteosarcoma.

Green composites are increasingly attracting interest due to their potential to address environmental issues by merging sustainable fillers with biodegradable polymers. The current study investigates the incorporation of zinc lignin hybrid (Zn-LSF) nanoparticles into a polyurethane matrix at varying ratios. The hybrid’s elemental composition was determined using X-ray fluorescence (XRF), and Energy-dispersive X-ray spectroscopy ( EDAX). The functional groups of both the hybrid and the prepared polyurethane films were identified by Fourier-transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) was employed to analyze the morphology of the Zn-LSF/polyurethane films. Mechanical properties and permeability were also evaluated. Furthermore, the antimicrobial activity and toxicity of the composites were assessed. The results demonstrated that the zinc lignin hybrid is non-toxic, provides antimicrobial properties, and enhances the mechanical strength of polyurethane along with a UV-shielding effect for the prepared polyurethane films. These findings suggest that, the prepared composites have potential as a sustainable, multifunctional additive for safe polyurethane food packaging.

Polystyrene membranes were found to be an effective-assisted material in the growth of undoped and doped indium–tin–oxide (ITO) with different concentrations from 3 to 7 wt% of CuO nanoparticles. Nanocomposites were characterized by XRD, FT-IR, HR-SEM/TEM, and dielectric measurements. Polystyrene-assisted ITO nanocomposites (ITO/PS) showed the high crystalline phase with lattice fringes, and well agreed on the cubic phase of ITO. As the concentration of CuO increases in ITO/PS nanocomposite, the conductivity decreases. Differential scanning calorimetry/thermogravimetric analysis showed a good thermal stability of the prepared nanocomposites. The increase of CuO wt% did not affect the major degeneration temperature and the thermal stability of undoped composite. The highest conductivity was obtained for ITO doped with 7 wt% of CuO. The formed Polystyrene-assisted ITO:Cu nanocomposites demonstrated a considerable antimicrobial activity against non-filamentous fungi ( Candida albicans ), Gram-positive bacteria ( Bacillus mycoides ), and Gram-negative bacteria ( Escherichia coli ) at all tested concentrations (3.0–7.0 wt% of CuO) with maximum activity at 7.0 wt% of CuO.