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      • KCI등재

        Polyaniline-engineered zinc sulphide nanocomposite as a highly efficient electrocatalyst for the oxygen evolution process

        Alenad Asma M.,Fatima Sofia,Khalid Usman,Bano Nigarish,Abid Abdul Ghafoor,Manzoor Sumaira,Farid Hafiz Muhammad Tahir,Messali Mouslim,Alzahrani Huda A.,Taha Taha Abdel Mohaymen 한국세라믹학회 2023 한국세라믹학회지 Vol.60 No.5

        Hydrogen is the ideal future fuel, since it is clean, saves energy, and is abundant in nature. Though there are several methods for producing hydrogen, only a few of them are environmentally friendly. To employ water electrolysis to make hydrogen and solve the energy shortage problem, highly active electrocatalysts must be created. Zinc sulphide/polyaniline (ZnS/PANI) nanocomposite was successfully produced using a straightforward two-step coprecipitation and polymerization procedure. Different analyses were used to characterize the fabricated materials. The findings show that the ZnS/PANI nanocomposite's morphology has a consistent porous shape, and the electrical structure of the active sites determines how well catalysts can make contact with the intermediates. Multiple attempts have been made to create the most affordable, functional electrocatalyst for oxygen evolution reactions (OER). However, clean energy production from such materials is sluggish. In comparison to pure PANI nanofibers (143.14 m2 g−1 and 0.4827 nm) and ZnS nanostructures (249.85 m2 g−1 and 0.4224 nm), the composite ZnS/PANI displays a greater Brunauer–Emmett–Teller (BET) surface area around 372.65 m2 g−1 along with nanoporous size of 0.393 nm due to the interaction, which provides distinctive features in contrast to ZnS and PANI. Synergistically, composite ZnS/PANI indicates lower overpotentials of 132 mV for oxygen evolution performance at 10 mA cm−2. An improved OER activity is observed by composite ZnS/PANIs as high current density, lower overpotential and reduced Tafel value of 53 mV dec−1. This catalyst also exhibited a significant double-layer capacitance and a large electrochemically active surface area. ZnS/PANI is a magnificent electrocatalyst for oxygen evolution.

      • Correlation of Preoperative Ki67 and Serum CA15.3 Levels with Outcome in Early Breast Cancers - a Multi Institutional Study

        Rasmy, A,Abozeed, W,Elsamany, S,El Baiomy, M,Nashwa, A,Amrallah, A,Hasaan, E,Alzahrani, A,Faris, M,Alsaleh, K,AlFaraj, A Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.7

        Background: To investigate the association between preoperative pathological Ki-67 labeling index and serum tumor marker cancer antigen 15-3 (CA 15-3) with clinic-pathological parameters and treatment outcomes in early breast cancer. Materials and Methods: A retrospective study at 4 cancer centers in Saudi Arabia and Egypt was performed. Data were collected for female patients diagnosed with unilateral early breast cancer between March 2010 and October 2013. Cases treated with neoadjuvant chemotherapy (NACT) followed by surgery and radiotherapy were included. NACT included 6-8 cycles of anthracycline and taxane based regimens. Trastuzumab and hormonal treatments were added according to HER2 and hormone receptor status. Baseline serum CA15.3 and pathological Ki67 levels were evaluated and correlated with disease free survival (DFS) and overall survival (OS). Results: A total of 280 pts was included. The median age was 49 years (38-66 y) and median overall survival was 35 (20-38) months (mo). Estrogen receptors (ER), progesterone receptors (PR) and HER 2 receptors were positive in 233 (83.2%), 198 (70%) and 65 cases (23.2%), respectively. High preoperative Ki67 and CA15.3 were noted in 177 (63.2%) and 131 (46.8%). A total of 45 (16%) patients had distal or local recurrence and 24 (8.6%) died of their disease. Most of the relapsed cases had high preoperative Ki-67 (n=41, 91%) and CA15.3 (n=28, 62%) values. All of the patients who died had a high Ki-67 but CA15.3 was high in 9 (37%) only. Mean DFS/OS in patients with high preoperative Ki-67 was 32 months /32 months as compared to 37 months/35 months in those with normal Ki-67 (p<0.001). Correlation of preoperative CA15.3 and survival was statistically not significant. Conclusions:Preoperative Ki-67 can be a predictive and prognostic marker. Higher levels are associated with poor DFS and OS in patients with early BC.

      • The Difference of Invariance, Reliability of The Student Engagement Scale (ESE) In Distance-Learning During Covid-19 Pandemic in Light of Some Students' Characteristics

        Almaleki, Deyab A.,Alzahrani, Abdulrahman J.,Alkhairi, Mohammed A.,Albalawi, Farhan A.,Albogami, Hosin A.,Alhajory, Easa S.,Readi, Wadea A.,Idrees, Mohammed A.,Alshamrani, Saleh M.,Alwusaidi, Osama A. International Journal of Computer ScienceNetwork S 2022 International journal of computer science and netw Vol.22 No.8

        This study aimed to test the factor structure of the measure of student participation in distance education. The study population consisted of all teachers in public education and faculty members in higher education in the Kingdom of Saudi Arabia by applying it to a sample of bachelor's and graduate students at the college of Education at umm al-Qura University. The (ESE) was applied to a random sample representing the study population consisting of (216) respondents. The results of the study showed that the scale consists of three main factors, with showed a high degree of construct validity through fit indices of the confirmatory factor analysis. The results have shown a gradual consistency of the measure's invariance that reaches the high level of the Measurement Invariance across the gender and study groups variables.

      • Predictive Value of IHC4 Score for Pathological Response to Neoadjuvant Chemotherapy in Hormone Receptor-Positive Breast Cancer

        Elsamany, Shereef,Elmorsy, Soha,Alzahrani, Abdullah,Rasmy, Ayman,Abozeed, Waleed N,Mohammed, Amrallah A,Sherisher, Mohamed A,Abbas, Mohammed M,Mashhour, Miral Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.17

        Purpose: This study aimed to explore the value of IHC4 in predicting pathological response after neoadjuvant chemotherapy in patients with hormonal receptor (HR)-positive breast cancer (BC). Materials and Methods: In this retrospective exploratory study, data for 68 HR-positive BC patients who received neoadjuvant chemotherapy were recorded. IHC4 scores were calculated based on estrogen receptors/progesterone receptors, Ki-67 and HER2 status. Logistic and ordinal regression analyses in addition to likelihood ratio test were used to explore associations of IHC4 scores and other clinico-pathological parameters with pathological complete response (pCR) and pathological stage. Results: Taking the 25th percentile as the cut-off, a lower IHC4 score was associated with an increased probability of pCR (low; 52.9% vs. High; 21.6%, OR=4.1, 95% CI=1.28-13.16, p=0.018) and a lower pathological stage (OR=3.9, 95% CI=1.34-11.33, p=0.012). When the IHC4 score was treated as a continuous variable, a lower score was again associated with an increased probability of pCR (OR=1.010, 95% CI=1.001-1.018, p=0.025) and lower pathological stage (OR=1.009, 95% CI=1.002-1.017, P=0.008). Lower clinical stage was associated with a better pCR rate that was of borderline significance (P=0.056). When clinical stage and IHC4 score were incorporated together in a logistic model, the likelihood ratio test gave a P-value of 0.004 after removal of the IHC4 score and 0.011 after removal of the stage, indicating a more significant predictive value of the IHC4 score for pCR. Conclusions: This study suggests that the IHC4 score can predict pathological response to neoadjuvant chemotherapy in HR-positive BC patients. This finding now needs to be validated in a larger cohort of patients.

      • A nonlocal system for the identification of active vibration response of chiral double walled CNTs

        Sami Alghamdi,Muzamal Hussain,Mohamed A. Khadimallah,Sehar Asghar,Emad Ghandourah,Ahmed Obaid M. Alzahrani,M.A. Alzahrani 국제구조공학회 2022 Steel and Composite Structures, An International J Vol.42 No.3

        In this study, an estimation regarding nonlocal shell model based on wave propagation approach has been considered for vibrational behavior of the double walled carbon nanotubes with distinct nonlocal parameters. Vibrations of double walled carbon nanotubes for chiral indices (8, 3) have been analyzed. The significance of small scale is being perceived by developing nonlocal Love shell model. The influence of changing mechanical parameter Poisson’s ratio has been investigated in detail. The dominance of boundary conditions via nonlocal parameter is shown graphically. It is found that on increasing the Poisson’s ratio, the frequencies increases. It is noted that the frequencies of clamped-clamped frequencies are higher than that of simply-supported and clamped-free edge conditions. The outcomes of frequencies are tested with earlier computations.

      • KCI등재

        Blocking Toll-like receptor 9 attenuates bleomycin-induced pulmonary injury

        Badr Alzahrani,Mohamed M. S. Gaballa,Ahmed A. Tantawy,Maha A. Moussa,Salma A. Shoulah,Said M. Elshafae 대한병리학회 2022 Journal of Pathology and Translational Medicine Vol.56 No.2

        Background: Acute respiratory distress syndrome (ARDS) is one of the most common complications in coronavirus disease 2019 patients suffering from acute lung injury (ALI). In ARDS, marked distortion of pulmonary architecture has been reported. The pulmonary lesions in ARDS include hemodynamic derangements (such as alveolar edema and hemorrhage), vascular and bronchiolar damage, interstitial inflammatory cellular aggregations, and eventually fibrosis. Bleomycin induces ARDS-representative pulmonary damage in mice and rats; therefore, we used bleomycin model mice in our study. Recently, Toll-like receptor 9 (TLR9) was implicated in the development of ARDS and ALI.Methods: In this study, we evaluated the efficiency of a TLR9 blocker (ODN2088) on bleomycin-induced pulmonary damage. We measured the apoptosis rate, inflammatory reaction, and fibroplasia in bleomycin- and bleomycin + ODN2088-treated mice.Results: Our results showed a significant amelioration in bleomycin-induced damage to pulmonary architecture following ODN2088 treatment. A marked decrease in pulmonary epithelial and endothelial apoptosis rate as measured by cleaved caspase-3 expression, inflammatory reaction as indicated by tumor necrosis factor α expression, and pulmonary fibrosis as demonstrated by Van Gieson staining and α-smooth muscle actin immunohistochemistry were observed following ODN2088 treatment.Conclusions: All these findings indicate that blocking downstream TLR9 signaling could be beneficial in prevention or mitigation of ARDS through hemodynamic derangements, inflammation, apoptosis, and fibrosis.

      • Artificial Intelligence Application using Nutcracker Optimization Algorithm to Enhance Efficiency & Reliability of Power Systems via Optimal Setting and Sizing of Renewable Energy Sources as Distributed Generations in Radial Distribution Systems

        Nawaf A. AlZahrani,Mohammad Hamza Awedh,Ali M. Rushdi International Journal of Computer ScienceNetwork S 2024 International journal of computer science and netw Vol.24 No.1

        People have been using more energy in the last years. Several research studies were conducted to develop sustainable energy sources that can produce clean energy to fulfill our energy requirements. Using renewable energy sources helps to decrease the harm to the environment caused by conventional power plants. Choosing the right location and capacity for DG-RESs can greatly impact the performance of Radial Distribution Systems. It is beneficial to have a good and stable electrical power supply with low energy waste and high effectiveness because it improves the performance and reliability of the system. This research investigates the ideal location and size for solar and wind power systems, which are popular methods for producing clean electricity. A new artificial intelligent algorithm called Nutcracker Optimization Algorithm (NOA) is used to find the best solution in two common electrical systems named IEEE 33 and 69 bus systems to examine the improvement in the efficiency & reliability of power system network by reducing power losses, making voltage deviation smaller, and improving voltage stability. Finally, the NOA method is compared with another method called PSO and developed Hybrid Algorithm (NOA+PSO) to validate the proposed algorithm effectiveness and enhancement of both efficiency and reliability aspects.

      • KCI등재

        Thermal energy performance due to convection process of nanofluid in a porous medium due to split lid motion in a right triangular enclosure

        Ullah M Zaka,Hussain S T,Haq Rizwan Ul,Alzahrani A Khamis,Mallawi Fouad 한국CDE학회 2022 Journal of computational design and engineering Vol.9 No.3

        In the current phenomena, a study is carried out for the convection process of nanofluid within the porous media enclosed in a triangular permeable cavity. The heat generation effect within the nanofluid is developed when the two heat sources are applied through the split lids. To analyse the behaviour of nanofluids and steam lines, we have considered an elliptic (cold, adiabatic, and heated)-shaped obstacle that is placed inside the cavity. Mathematical modelling is carried out through continuity, momentum equation, and energy equations in the form of a system of non-linear partial differential equations. These equations are produced after incorporating the relations of viscosity, density, shapes of nanoparticle, and thermal conductivity for nanofluids Constraints are adjusted according to the forced convection due to the upper moving wall of the cavity. Four different cases of the upper double lid-driven wall are considered. All the emerging parameters, namely Reynolds number $( {25 \le {\rm{Re}} \le 750} ),$ heat generation $( { - {{10}^4} \le Q \le 40} ),\ $ nanoparticle volume fraction $\ ( {0 \le \phi \le 0.2} )$, and Darcy number ${10^{ - 5}} \le Da \le {10^{ - 3}}$, are analysed through variation of velocities, temperature profile, isotherms, and streamlines. Various cases at the surface of the inner elliptical obstacle provide significant contributions in the variation of heat transfer rate and velocity profiles. Nanoparticles provide a considerable increase in the heat transfer rate. The Darcy number shows the substantial variation in the formation of the isothermal region. An increase in heat generation parameter Q provides an improvement in temperature distribution inside the cavity and it also caused the formation of a single isothermal region around the heated obstacle.

      • KCI등재

        Biochemical and ultrastructural changes in the ovaries of red palm weevil, Rhynchophorus ferrugineus (Coleoptera: Curculionidae) following acute imidacloprid poisoning

        Salaheldin A. Abdelsalam,Abdullah M. Alzahrani,Omar M. Elmenshawy,Azza Sedky,Ashraf M. Abdel-Moneim 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.3

        This study aims to inspect the effects of Imidacloprid (IMI) acute toxicity in the ovaries of the red palm weevil (Rhynchophorus ferrugineus). The LC50 of IMI was determined to be 15.7 ppm. We assessed the biochemical changes resulting from treatment with four IMI concentrations (10, 15, 20 and 30 ppm). IMI reduced acetylcholine esterase activity in a dose-dependent manner. Glutathione (GSH) content decreased with increasing concentration of IMI; however, GSH was not affected and accompanied by an increase in catalase activity with the highest concentration of IMI. Lipid peroxidation increased steadily as IMI concentration increased. Based on the ultrastructural analyses of the follicle cells and the ooplasm of developing oocytes, acute IMI toxicity produced damaged yolk bodies, pale nuclei, and shrinking microvilli. Fractionation of rough endoplasmic reticulum, deformed mitochondria, and autophagic bodies were also observed. In conclusion, these ovarian pathobiochemical changes could be used as biomarkers of acute IMI exposure.

      • KCI등재

        Facile synthesis of SmSe2 over multiwalled carbon nanotubes for efficient water-splitting applications

        Alenad Asma M.,Aman Salma,Ahmad Naseeb,Rashid Abdul Rasheed,Abid Abdul Ghafoor,Manzoor Sumaira,Nisa Mehar Un,Messali Mouslim,Alzahrani Huda A.,Taha Taha Abdel Mohaymen 한국세라믹학회 2024 한국세라믹학회지 Vol.61 No.1

        The next generation of lightweight, flexible electronic equipment allows mechanical bending compatible with roll-to-roll technologies. In a novel method, a hydrothermal, wide potential is applied for the synthesis of samarium selenide–multiwalled carbon nanotubes (SmSe2–MWCNT) composite material. The chemical and physical characteristics for SmSe2–MWCNT are investigated with electrochemical assessments and X-ray diffraction (XRD) as well as via scanning electron microscopy (SEM). Under alkaline conditions, the SmSe2/MWCNT electrocatalyst shows a good activity for oxygen evolution reaction (OER). SmSe2–MWCNT nanocomposites appear to be good OER candidates in alkaline environments because of high ratio of catalytically active sites and faster electron movement, which increased the material’s conductivity, with current density, overpotential, and Tafel slope of 10 mA cm−2, 315 mV, and 73 mV dec−1, respectively, and displayed decent stability of 20 h via chronoamperometry test. The findings demonstrate that the SmSe2–MWCNT electrode could be employed as a potential candidate for hydrogen production.

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