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In this study, we investigate an optimized design of ZnO/BaZrS3/BaZr1−0.95Ti0.05S3 chalcogenide perovskites solar cells using a theoretical model that considers different recombination mechanisms effect in terms of bulk recombination, interface recombination and tunneling enhanced recombination. The influence of thickness and doping of both window and absorber layers, as well as the absorber band gap, was investigated using the proposed model. The model was validated through numerical simulations, showing a good agreement. The proposed model is utilized as the fitness criterion within the MOPSO framework to optimize the solar cell performance. The optimized design achieved an efficiency of 12.26%, outperforming the conventional design with an efficiency of 8.66%. This significant improvement underscores the effectiveness of tuning band alignment at the interface and also to the global design optimization strategy in enhancing the performance of chalcogenide perovskite solar cells. [ABSTRACT FROM AUTHOR]

An alternative synthesis route to obtain ultramicroporous zeolitic imidazolate framework‐8 (ZIF‐8) is reported that is rapid and does not require organic solvent or heating. The polyethylene glycol‐templated ZIF‐8 nanoparticles (<50 nm size) exhibited a high BET (Brunauer, Emmett and Teller) surface area of 1853 m2/g, a total pore volume of 0.73 cm3/g, and 0.54 nm ultramicropores. A new approach is introduced here to better understand gas adsorption in porous metal organic frameworks (MOFs) that combines theoretical and experimental isotherm data obtained for five gases with statistical physics modelling. The multiscale analytical model reveals that the gas molecules, irrespective of their structure, adsorb in a mixed orientation at low temperature, and a parallel multi‐molecular orientation at higher temperature. The number of gas molecules adsorbed per site ranged from 0.83–2.2 while the number of adsorbent layers ranged between 1.4–5.6, depending on the gas and the temperature. The multilayer adsorption processes involved adsorption energies from 2.85 kJ/mol–9.77 kJ/mol for all gases, consistent with physisorption via van der Waals and London dispersion forces. The initial adsorption energies were higher and therefore stronger. A particularly high capacity for CO2 of 1088 mg(CO2)/g at 298 K was observed while H2 adsorption was only 9 mg(H2)/g. The other gases adsorbed at 145 mg/g–245 mg/g at 298 K. Thermodynamic functions that governed the adsorption process such as the internal energy, the enthalpy, and Gibbs free energy, are also reported, as well as the adsorption entropies, for the 5 gases. [ABSTRACT FROM AUTHOR]

This article aims to introduce a set of hybrid matrix polynomials associated with λ-polynomials and explore their properties using a symbolic approach. The main outcomes of this study include the derivation of generating functions, series definitions, and differential equations for the newly introduced two-variable Hermite λ-matrix polynomials. Furthermore, we establish the quasi-monomiality property of these polynomials, derive summation formulae and integral representations, and examine the graphical representation and symmetric structure of their approximate zeros using computer-aided programs. Finally, this article concludes by introducing the idea of 1-variable Hermite λ matrix polynomials and their structure of zeros using a computer-aided program.

Smart cities like Neom require efficient and reliable transportation systems to support their vision of sustainable and interconnected urban environments. High-speed trains (HSTs) play a crucial role in connecting different areas of the city and facilitating seamless mobility. However, to ensure uninterrupted communication along the rail lines, advanced communication systems are essential to expand the coverage range of each base station (BS) while reducing the handover frequency. This paper presents the dual transceiver free space optical (FSO) communication system as a solution to achieve these objectives in the operational environment of HSTs in Neom city. Our channel model incorporates log-normal (LN) and gamma–gamma (GG) distributions to represent channel impairments and atmospheric turbulence in the city. Furthermore, we integrated the siding loop model, providing valuable insights into the system in real-world scenarios. To assess the system’s performance, we formulated the received signal-to-noise ratio (SNR) of the network under assumed fading conditions. Additionally, we analyzed the system’s bit error rate (BER) analytically and through Monte Carlo simulation. A comparative analysis with reconfigurable intelligent surfaces (RIS) and relay-assisted FSO communications shows the superior coverage area and efficiency of the dual transceiver model. A significant reduction of up to 76% and 99% in the number of required BSs compared to RIS and relay, respectively, is observed. This reduction leads to fewer handovers and lower capital expenditure (CAPEX) costs.

This study investigates the genetic determinants of seed coat color and pattern variations in cowpea (Vigna unguiculata), employing a genome-wide association approach. Analyzing a mapping panel of 296 cowpea varieties with 110,000 single nucleotide polymorphisms (SNPs), we focused on eight unique coat patterns: (1) Red and (2) Cream seed; (3) White and (4) Brown/Tan seed coat; (5) Pink, (6) Black, (7) Browneye and (8) Red/Brown Holstein. Across six GWAS models (GLM, SRM, MLM, MLMM, FarmCPU from GAPIT3, and TASSEL5), 13 significant SNP markers were identified and led to the discovery of 23 candidate genes. Among these, four specific genes may play a direct role in determining seed coat pigment. These findings lay a foundational basis for future breeding programs aimed at creating cowpea varieties aligned with consumer preferences and market requirements.

A noteworthy advancement within the discipline of q-special function analysis involves the extension of the concept of the monomiality principle to q-special polynomials. This extension helps analyze the quasi-monomiality of many q-special polynomials. This extension is a helpful tool for considering the quasi-monomiality of several q-special polynomials. This study aims to identify and establish the characteristics of the 2-variable q-Hermite–Appell polynomials via an extension of the concept of monomiality. Also, we present some applications that are taken into account.

In this paper, by using the Golden Calculus, we introduce the generalized Apostol-type Frobenius–Euler–Fibonacci polynomials and numbers; additionally, we obtain various fundamental identities and properties associated with these polynomials and numbers, such as summation theorems, difference equations, derivative properties, recurrence relations, and more. Subsequently, we present summation formulas, Stirling–Fibonacci numbers of the second kind, and relationships for these polynomials and numbers. Finally, we define the new family of the generalized Apostol-type Frobenius–Euler–Fibonacci matrix and obtain some factorizations of this newly established matrix. Using Mathematica, the computational formulae and graphical representation for the mentioned polynomials are obtained.

A powerful steroid hormone precursor, 1,25 dihydroxycholecalciferols (1,25(OH)2D3), and dietary phytoestrogen (genistein) are essential compounds that act by binding to nuclear receptors and altering gene expression. They have many biological benefits, some of which have anticancer properties. We studied the impact of 1,25(OH)2D3 and genistein on the proliferation, progression, and metastasis of MCF-7 and MDA-MB-231 cells when they were used alone or in combination and investigated whether there was a synergistic effect between genistein and 1,25(OH)2D3. To achieve these goals, a variety of assays, including flow cytometry, cell invasion assays, cell adhesion assays, Western blotting, and RT‒PCR, were used.Our findings showed that genistein, 1,25(OH)2D3, and the two combined all effectively declined the growth of MCF-7 and MDA-MB-231 cells by arresting the cells in the G0/G1 phase and inducing an apoptotic pathway. Stimulation of apoptosis was achieved by upregulating the expression of BAX and CASP3 genes and downregulating the expression levels of BCL-2 gene. Furthermore, both compounds suppress metastasis by reducing cell adhesion and cell migration/invasion by elevating the expression level of E-cadherin and reducing the expression level of P-cadherin and N-cadherin. Additionally, both genistein and 1,25(OH)2D3 increased the expression level of ERK1 and reduced the expression levels of JNK, p38, Ras, and MEK proteins, which reduced metastasis, enhanced the response to cancer treatment, and improved overall survival. Thus, genistein and 1,25(OH)2D3 can both be considered key candidates in the search for new breast cancer treatments.

Abstract Lithium-ion batteries based on high-voltage cathode materials, such as LiCoPO4, despite being promising in terms of specific power, still suffer from poor cycle life due to the lower stability of common non-aqueous electrolytes at higher voltages. One way to overcome this issue might be decreasing the working potential of the battery by doping LiCoPO4 by Fe, thus reducing electrolyte degradation upon cycling. However, such modification requires a deep understanding of the structural behavior of cathode material upon lithiation/delithiation. Here we used a combination of operando synchrotron-based XRD and XAS to investigate the dynamics of d-metal local atomic structure and charge state upon cycling of LiCo0.5Fe0.5PO4 mixed d-metal olivine cathode material. Principal components analysis (PCA) of XAS data allowed the extraction of spectra of individual phases in the material and their concentrations. For both Co and Fe two components were extracted, they correspond to fully lithiated and delithiated phases of LixMPO4 (where M = Fe, Co). Thus, we were able to track the phase transitions in the material upon charge and discharge and quantitatively analyze the M2+/M3+ electrochemical conversion rate for both Fe and Co. Rietveld's refinement of XRD data allowed us to analyze the changes in the lattice of cathode material and their reversibility upon (de)lithiation during cycling. The calculation of DFT and Bader charge analysis expects the oxygen redox procedure combined with d-metals redox, which supplements iron charge variations and dominates at high voltages when x

Conclusions: The results of this study provide an overview of the variations in microbiota diversity present in Saudi IBD patients compared to healthy controls. Results: The key finding was three negative bacterial biomarkers, Paraprevotellaceae, the Muribaculaceae families of Bacteroidetes phylum, and the Leuconostocaceae family of Firmicutes phylum, which had a higher relative abundance in healthy individuals compared to IBD patients. It was also found that primary microbiota signatures at certain genera and species levels, including Prevotella copri, Bifidobacterium adolescentis, Ruminococcus callidus, Coprococcus sp., Ruminococcus gnavus, Dorea formicigenerans, Leuconostoc, Dialister, Catenibacterium, Eubacterium biforme, and Lactobacillus mucosae, were absent in almost all IBD patients, while Veillonella dispar was absent in all healthy individuals. Methods: After obtaining an informed consent, fecal samples were collected from 11 participants with IBD (patients) and 10 healthy individuals (controls). The bacterial components of the microbial population were identified by next-generation sequencing of partial 16S rRNA. Statistically significant dissimilarities were observed between samples for all metrics. Background: Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory condition attributed to a complex interaction between imbalances in the gut microbiome, environmental conditions, and a deregulated immune response. The aim of the study was to investigate the composition of the gut microbiome of Saudi patients with IBD.

The polyaniline-based nanocomposite is a promising candidate for hosting sulfur in cathode materials-based lithium-sulfur batteries. This is because of its strong affinity towards lithium polysulfide and high conductivity. However, with its lower specific surface area and the less polar group, frame structures are unstable, limiting their performance in electrochemical energy storage devices. We have developed PANI – GO – S nanocomposite in ice to grow continuous well-ordered pores structures with high conductivity. The prepared nanocomposite (1 wt%) was mixed with LiNi0.5Mn0.5O2 with polyvinylidene fluoride (PVDF) in N-methyl pyrrolidone (NMP) solvent to make the slurry for the cathode fabrication. The cyclic voltammetry of PANI and its nanocomposite indicates a typical characteristic of the redox peaks at 1.9 V and 2.7 V and the oxidation peak appeared at 2.6 V and 2.2 V that indicates the changing into Li2S to S2− and later sulfur elemental S8. The high specific capacity of the LNMO (PANI – GO – S) nanocomposite obtained 868 mAh g−1 up to 400 cycles and above that its value around is around 748 mAh g−1 with the retention rate of 76 % with the same coulomobic efficiency of 98% confirms that the nanocomposite high stability and high corrosion resistance. This outcome of the LNMO (PANI – GO – S) nanocomposite presents a new strategy to fabricate advanced cathodes and high specific capacity of the cathode in a lithium-based electrochemical charge storage cell.

Hanan E Alyahyawi,1 Raed A Alharbi,1 Saleha Keder Alatawi,2 Waled AM Ahmed,3 Shaia SR Almalki1 1Department of Laboratory Medicine, Faculty of Applied Medical Sciences, Albaha University, Al Bahah, Saudi Arabia; 2Department of Optometry, Faculty of Applied Medical Sciences, Albaha University, Al Bahah, Saudi Arabia; 3Department of Nursing, Faculty of Applied Medical Sciences, Albaha University, Al Bahah, Saudi ArabiaCorrespondence: Shaia SR Almalki, Department of Laboratory Medicine, Faculty of Applied Medical Sciences, Albaha University, Al Bahah, Saudi Arabia, Tel +966- 556556714, Email shalmalki@bu.edu.saAbstract: The global pandemic of coronavirus disease 2019 (COVID 19) is reported to have started in Wuhan City, Hebei Province, China. It has spread rapidly all over the world, including Saudi Arabia, having a severe health emergency. This new virus was named as the 2019 novel coronavirus (2019-nCoV), and now severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) based on previous practice and phylogenetic and taxonomic investigations. SARS-CoV-2 belongs to the family of Coronaviridae, Betacoronavirus, Sarbecovirus subgenus, genome β. Throughout the COVID 19 pandemic, several strains of SARS-CoV-2 have been recognized around the world. The SARS-CoV-2 variants have caused significant morbidity and mortality worldwide and in Saudi Arabia as well. The rate at which COVID-19 spread across borders and affected countries has highlighted the significance of health care systems to nations and global operations. This review focuses on the origin, epidemiology, pathophysiology, transmission, and the impact of this disease, while highlighting the knowledge about SARS-CoV-2 variants.Keywords: prevalence, incidence, COVID-19, coronavirus, SARS-CoV-2, review

Abstract Background Immune checkpoint inhibitors, including PD-L1 (programmed death ligand-1) inhibitors have well documented anticancer therapeutic effect in most types of cancers but its use in the treatment of ovarian cancer is not yet proven. The aim of our study is to explore the predictive biomarkers in ovarian cancer and its association with the outcomes. We have investigated the role of PD-L1 expressions in the tumor microenvironment cells including immune cells and cancer stem cells in different types of ovarian cancer. Methods A total of 119 surgical archived ovarian cancer samples were collected from the pathology department at King Fahad Specialist Hospital, Dammam, Saudi Arabia that included serous carcinomas, clear cell carcinomas, mucinous carcinomas, endometrioid carcinomas, and granulosa cell tumors. Immunohistochemistry (IHC) staining was performed using (i) PD-L1 antibodies to detect PD-L1 expressions; (ii) CD8 and CD4 to detect Tumor Infiltrating Lymphocytes (TILs); and (iii) CD44, LGR5, and ALDH2 to detect stem cell markers. The clinicopathological data were collected from patients’ medical record to investigate the association with PD-L1, TILs, and stem cells expressions. Results We report high PD-L1 expressions in 47.8% of ovarian cancer samples. PD-L1 expressions were detected in different types of epithelial ovarian cancer and were not associated with poor prognosis of ovarian cancer. However, determining the expression levels of TILs in the ovarian cancer tissues found that 81% (n = 97) of ovarian cancer samples have TILs that express both of CD8 and CD4 and significantly associated with high PD-L1 expressions. Interestingly, we have found that ovarian cancer tissues with high expressions of PD-L1 were associated with high expressions of stem cells expressing CD44 and LGR5. Conclusions PD-L1 is highly expressed in the serous type of ovarian carcinomas and the overall expression of PD-L1 is not associated with poor survival rate. Furthermore, PD-L1 expressions are strongly associated with TILs and stem cell markers in ovarian cancer. Inhibiting the PD-L1 using immune checkpoint inhibitors might downregulate stem cell population that known to be associated with cancer recurrence.

In forensic toxicology, precise determination of toxic trace metals in biological samples is critical. Inductively coupled plasma optical emission spectrometry (ICP OES), which has a low limit of detection, high sensitivity, accurate testing, and high analytical efficiency, is one of the most widely used techniques for determining the level of toxic trace metals in biological samples. This study aimed to assess the efficiency of ICP-OES in estimating cadmium (Cd) and lead (Pb) in whole blood samples when viewed axially, dual, and radially. All the samples that were analyzed were digested in 1.5 ml HNO3 and 2 ml H2O2. Selectivity, linearity, recovery, limits of detection (LOD), and quantification (LOQ) were used to validate the system. Cd-axial and radial recovery values were between 82–96 and 84–97%, while Pb-axial and radial recovery values were between 85–94 and 83–99%. Dual Cd-axial and radial recovery values were between 80–92 and 82–94%, while dual Pb-axial and radial recovery values were between 77–92 and 75–96%. The results demonstrated that the axillary and radially view is preferable to the dual view when using separate axially and radially view inductively coupled plasmas (ICP). In axillary and radially views, Cd's recovery rates were better than Pb's in the separate mode, but overall they were satisfactory. The recovery values for Cd and Pb in the dual view were acceptable but not sufficient.

The present paper highlights heat transfer and entropy generation due to mixed convection for an inclined channel. The channel is heated by its upper wall and cooled by two jets of nanofluids penetrating through its lower wall. The studied configuration is chosen to model, in qualitative way, a cooling system for photovoltaic panel. The set of partial differential equations that governing the flow was numerically solved using COMSOL software. Effects of the inclination angle of the channel, Reynolds number and nanoparticles fraction, on heat transfer, hydrodynamic and created entropy are examined. The inclination angle, the Reynolds number and the nanoparticle fraction are ranging from 0° to 30°, from 50 to 150 and from 0% to 8% respectively. It was found that the effect of the angle of inclination, on heat transfer and thermal irreversibility, is weak and that it cannot exceed 2%. Whereas the nanofluid concentration and the Reynolds numbers alter at once the created entropy and the heat transfer. Results show an increase of nearly 15% of Nusselt number and thermal irreversibility when the nanoparticle concentration reaches 8%. The local irreversibility maps reveal that the created entropy is significantly localized at the impact locations of the cooling jets. Since irreversibility is synonymous with the aging of the system, which naturally leads to usury, it can be concluded that the channel may be damaged at these locations.