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Mostafa A Abolfotouh,1 Adel F Almutairi,2 Zainab Almutairi,3 Mahmoud Salam,2 Anwar Alhashem,1 Abdallah A Adlan,4 Omar Modayfer5 1Research Training and Development Section, King Abdullah International Medical Research Center/ King Saud bin-Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia; 2Science and Technology Unit, King Abdullah International Medical Research Center/ King Saud bin-Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia; 3Stem Cells Donor Registry, King Abdullah International Medical Research Center/ King Saud bin-Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia; 4Bioethics Section, King Abdullah International Medical Research Center/ King Saud bin-Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia; 5Division of Mental Health, King Abdulaziz Medical City, Ministry of National Guard-Health Affairs, Riyadh, Saudi Arabia Background: It has been reported that the majority of individuals with mental illnesses (MIs) do not seek help. Few studies have focused on correlates of a positive attitude toward professional help-seeking for MI. This study aimed to determine levels of knowledge, perception, and attitudes toward MI, determine attitudes toward mental health help-seeking, and identify sociodemographic predictors of correct knowledge and favorable attitudes among the Saudi public. Methods: A cross-sectional survey was conducted on 650 Saudi adults aged >18 years who attended the Saudi Jenadriyah annual cultural and heritage festival during February 2016. The previously validated Attitudes to Mental Illness Questionnaire was used. Attitude to professional help-seeking was also assessed, using a tool retrieved from the World Mental Health Composite International Diagnostic Interview part II. Multiple regression analyses were applied, and statistical significance considered at P0.05). Conclusion: The Saudi public reported lack of knowledge of MI and stigmatizing attitudes toward people with MI in relation to treatment, work, marriage, and recovery and toward professional help-seeking. Sociodemographic characteristics predicted correct knowledge and favorable attitudes, while Saudi culture was the likely factor behind negative judgments about mentally ill persons. Efforts to challenge this negative publicity and stigma through antistigma campaigns and public education through schools and media are recommended. Keywords: psychiatric illness, discrimination, people with mental illness, PWMI, stigma, antistigma, negative publicity, judgment of mental issues, professional help-seeking, social distance

Mahmoud A Mahmoud,1 Zaid Saud Almutairi,2 Abdulrahman M Mahmoud,2 Hind Bashir Alanazi,2 Sundus M Abdulrahman,2 Khalid A Bin Abdulrahman3 1Department of Family and Community Medicine, College of Medicine, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, Kingdom of Saudi Arabia; 2College of Medicine, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, Kingdom of Saudi Arabia; 3Department of Medical Education, College of Medicine, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, Kingdom of Saudi ArabiaCorrespondence: Mahmoud A Mahmoud, Email drmhmod@gmail.comBackground: Public health education increasingly emphasizes experiential learning and community engagement. Peer review complements traditional staff evaluation, enhancing learning outcomes and refining teaching strategies. This study aims to investigate the perceptions and experiences of medical students with peer evaluation of community health projects. Staff evaluation for the same projects will be used for comparison.Methods: A cross-sectional survey study involving medical students from the epidemiology and community health course at the College of Medicine, Imam Mohammad Ibn Saud Islamic University (IMSIU). Students assessed their peers’ community health projects using a self-administered questionnaire. Staff evaluations were also compared. Data was analyzed by IBM SPSS 29.Results: The study included 187 participants, primarily medical students (98.3%), who evaluated 20 community health projects. Three teaching staff members also rated the same projects. Medical students ranked effort expended (4.34), topic importance (4.26), and apparent participation (4.26) in descending order of value. The Staff evaluated the topic’s relevance as the highest (4.43), but they rated the tools as lower (3.9). Medical students ranked tools sufficiency significantly higher, with a mean of (4.16 vs 3.90) than Staff (p < 0.05). Both groups evaluated the project’s level of innovation and the clarity of its target audience in a comparable manner. The analysis of the Full Project Level indicated no substantial disparity between medical students and Staff, as evidenced by the p-value of 0.920.Conclusion: This study validates that peer evaluation of student projects is equally practical as evaluation conducted by faculty members. Consequently, allocating resources toward enhancing peer students’ learning and evaluation capabilities is justifiable.Keywords: student peer evaluation, medical students, community health, student projects, Saudi Arabia

In healthcare applications, automatic and intelligent movement recognition systems in Ambient Assisted Living (AAL) are designed for elderly and disabled persons. The AAL provides assistance as well as secure feelings to disabled persons and elderly individuals. In AAL, the movement recognition process has been emerging in recent days. The automatic and safe living of the disabled person is ensured by performing movement recognition in AAL. Movement recognition in the AAL is developed for disabled and elderly people and is also performed to provide healthcare assistance to the elderly and disabled person. The weighted deep learning model and a hybrid heuristic algorithm are proposed to achieve this goal. The required input data is initially gathered from the standard data sources. Subsequently, the essential deep features are extracted from the input data using a Convolutional Autoencoder. Finally, the resultant features are subjected to the movement recognition model, termed as Weighted Residual Recurrent Neural Network. For achieving a better training and testing process, the weights in the RRNN model are optimally selected by using the hybrid algorithm named Hybrid Rat Swarm with Coati Optimization Algorithm, which is developed with the integration of the Rat Warm Optimization and Coati Optimization. The movement recognition results are used for providing medical assistance to elderly and disabled persons. Lastly, the efficacy of the suggested strategy is validated with different measures. From the experiments, the proposed system attains standard results in terms of improved system performance and accuracy that can aid in significantly recognizing human movements., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Multifunctional polymer composites containing micro/nano hybrid reinforcements have attracted intensive attention in the field of materials science and engineering. This paper develops a multi-phase analytical model for investigating the effective electrical conductivity of micro-silicon carbide (SiC) whisker/nano-carbon black (CB) polymer composites. First, CB nanoparticles are dispersed within the non-conducting epoxy to achieve a conductive CB-filled nanocomposite and its electrical conductivity is predicted. Some critical microstructures such as volume percentage and size of nanoparticles, and interphase characteristics surrounding the CB are micromechanically captured. Next, the electrical conductivity of randomly oriented SiC-containing composites in which the nanocomposite and whisker are considered as the matrix and reinforcement phases, respectively, is estimated. Influences of whisker aspect ratio and volume fraction on the effective electrical conductivity of the SiC/CB-containing polymer composites are explored. Some comparison studies are performed to validate the accuracy of the model. It is observed before the percolation threshold that the addition of nanoparticles with a uniform dispersion can improve the electrical conductivity of the polymer composites containing SiC/CB hybrids. Moreover, the results show that the electrical conductivity is more enhanced by the decrease in nanoparticle size. Interestingly, the composite percolation threshold is significantly reduced when SiC whiskers with a higher aspect ratio are added. This work will be favorable for the design of electro-conductive polymer composites with high performances.

Ingestion of foreign bodies, particularly button batteries (BB), is a common pediatric emergency. Esophageal impaction of BB is associated with life-threatening complications. Damage can be manifested within hours from ingestion; therefore, immediate removal is recommended. A 23-month-old boy presented to the emergency department following an incidental chest X-ray that revealed a BB lodged in the upper esophagus, initially overlooked during a prior visit. The family reported that the child had been experiencing persistent cough, intermittent fever, vomiting, and poor oral intake over the last two months. Upon admission, the child was stable, but laboratory tests indicated elevated inflammatory markers. A multidisciplinary team was promptly assembled for management, leading to a successful extraction of the BB in the operating room. Postoperatively, the child developed secondary hemophagocytic lymphohistiocytosis and methicillin-sensitive Staphylococcus aureus infection, which were effectively treated. After discharge, the patient was followed up in the clinic, and no complications were observed. Although BB ingestions are not the commonest among all types of foreign body ingestion, their serious complications have been evidence-based published., Competing Interests: Human subjects: Consent for treatment and open access publication was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Abaalkhail et al.)

This laboratory study aimed to evaluate the effect of different surface patterns using femtosecond laser treatment on the enclosed mold shear bond strength (EM-SBS) of resin composite to zirconia (ZrO 2 ) surfaces and to contrast it with the widely used tribochemical silica coating (TBC) surface conditioning method. A set of fifteen rectangular ZrO 2 blocks were randomly divided into five groups according to surface pretreatment: Control G 0 -no treatment; G 1 -TBC with silane application; G 2 -femtosecond laser irradiation with horizontal lines 30 µm apart; G3 -femtosecond laser irradiation with horizontal lines 15 µm apart; and G 4 -femtosecond laser irradiation with cross lines 30 µm apart. The pretreated surfaces were characterized by a surface profilometer, tensiometer and scanning electron microscope. The EM-SBS of resin composite stubs to ZrO 2 was measured followed by fractographic analysis. The surface roughness and water contact angle were observed to be statistically higher among the femtosecond laser groups compared to the TBC and control groups. The G 4 group exhibited the highest EM-SBS among all the groups, irrespective of the ageing conditions used. At the end of 5000 thermocycles, G 4 exhibited EM-SBS of 14.05 ± 4.21 MPa compared to 13.80 ± 3.01 MPa in G 1 and 5.47 ± 0.97 MPa in G 0 . The two-way ANOVA revealed a significant effect of both study groups and ageing conditions on the EM-SBS ( p < 0.001). Utilization of femtosecond laser technology holds promise as a potential and alternative mechanical retention approach for enhancing the bonding strength of the resin composite to ZrO 2 .

Methods: A retrospective analysis of patients aged ≥18 years and having dental implants placed at Dubai Health Authority in 2010. Relevant information related to systemic-, patient-, implant-, site-, surgical- and prosthesis-related factors were collected. The strength of association between the prevalence of peri-implant mucositis and peri-implantitis and each variable was measured by chi-square analysis. A binary logistic regression analysis was performed to identify possible risk factors., Results: A total of 162 patients with 301 implant-supported restorations were included in the study. The age of the patients ranged between 19 and 72 with a mean age of 46.4 ± 11.7 years. The prevalence of peri-implant mucositis at the patient and implant levels were 44.4% and 38.2%, respectively. For peri-implantitis, the prevalence at the patient level was 5.6%, while the prevalence at the implant level was 4.0%. The binary logistic regression identified three risk factors (smoking habits, histories of treated periodontitis and lack of peri-implant maintenance) for peri-implantitis., Conclusion: Within the limitations of this study, smoking habits, history of treated periodontitis and lack of peri-implant maintenance were significant risk factors for peri-implantitis. Early detection of these factors would ensure appropriate planning and care of patients at high risk of developing peri-implant diseases., Competing Interests: The authors report no conflicts of interest related to this review., (Copyright © 2022 Momen A. Atieh et al.)

Utilizing solid particles as a heat-transfer medium in concentrated solar power applications has gained growing attention lately. Unlike molten salts, solid particles offer many benefits, which include: high operating temperatures (greater than 1000 °C), a lack of freezing issues and corrosivity, abundant availability, high thermal energy storage capacity, a low cost, and applicability in direct irradiation. Comprehensive knowledge of thermophysical and optical properties of solid particles is essential to ensure an effective harnessing of solar energy. The most important considerations when selecting solid particles include: thermophysical and optical properties, thermal resistance, crack resistance, satisfactory health and safety risks, availability, and low cost. It is also imperative to consider optical and thermophysical characteristics that might change from what they were "as received" after cyclic heating for a long period. Therefore, the knowledge of thermal performance of particulate materials becomes significant before using them as a heat-transfer medium. In this study, some particulate materials were chosen to study their feasibilities as heat-transfer and storage media for a particle-based central receiver tower system. These particulate materials included white sand, red sand, ilmenite, and Carbobead CP. The candidate particulate materials were heated at high temperatures for 6 h and then cooled to room temperature. After that, cyclic heating was performed on the particulate materials for 500 h at 1200 °C. The optical properties were represented by weighted solar absorptance, and the thermophysical properties of the particulates were measured "as received" and after cyclic heating (aging). EDX and XRD were conducted to quantify the chemical composition and interpret the changes in appearance associated with the particulate materials after cyclic heating. The results showed a considerable agglomeration in all particulates except for white sand in the 6 h heating test, and high agglomeration in the ilmenite. A slight decrease in the optical properties in the white sand and Carbobead CP was found after the aging test. The specific heat was decreased for red and white sand. The EDX and XRD results for white sand and Carbobead CP showed chemical stability, indicating high durability and reliability.

Finding HLA-matched donors for patients in need of hematopoietic stem cell transplantation (HSCT) stands a better chance in their own ethnic group. This information led many nations to establish unrelated stem cell donor registries. We started our Saudi Stem Cell Donor registry (SSCDR) in 2011. The calculated donor pool size was nearly 1 million donors to find a matched donor for every patient. So far we have recruited 75,145 donors. In this exercise we attempted to investigate the chances of finding a matched donor for Saudi patients in need of HSCT. A total of 445 patients were recruited for this study. Donor searches were carried out locally and internationally using Prometheus software and World Marrow Donor Association Search and Match Service, respectively. Only 24% of the patients found a matched donor in our registry, 12% found a donor in other registries, making it a total of 36% of our patients who have the chance to find a full 10/10 HLA-matched donor. However, when we included 9/10 and 8/10 with the full matched donors, the chances go up to 83%. The top scoring registries for number of patients finding 10/10 matched donors were SSCDR (108), Deutsche Stammzellspenderdatei Nabelschnurblut (n = 52), King Faisal Specialist Hospital & Research Centre Stem Cell Donor Registry (n = 52), NMDP-National Marrow Donor Program/Be The Match (n = 43), TURKOK-Turkish Stem Cell Coordination Centre (n = 39), DKMS United Kingdom (n = 24), and Ezer Mizion Bone Marrow Donor Registry (n = 20). The patient who found the highest number of donors in international registries carried the European haplotype A1-B8-DR3; a total of 272 donors were found, and none of them were from our registry. Patients with the highest matched donor numbers in SSCDR carried haplotypes that were not common in international registries. Having a local registry increases the chances of finding a matched donor for our patients; however, international registries can still add to the chances of finding matched donors. Increasing our donor pool will increase chances of our patients finding a matched donor., (Copyright © 2021 The American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Two-dimensional (2D) materials 1,2 and the associated van der Waals (vdW) heterostructures 3-7 have provided great flexibility for integrating distinct atomic layers beyond the traditional limits of lattice-matching requirements, through layer-by-layer mechanical restacking or sequential synthesis. However, the 2D vdW heterostructures explored so far have been usually limited to relatively simple heterostructures with a small number of blocks 8-18 . The preparation of high-order vdW superlattices with larger number of alternating units is exponentially more difficult, owing to the limited yield and material damage associated with each sequential restacking or synthesis step 8-29 . Here we report a straightforward approach to realizing high-order vdW superlattices by rolling up vdW heterostructures. We show that a capillary-force-driven rolling-up process can be used to delaminate synthetic SnS 2 /WSe 2 vdW heterostructures from the growth substrate and produce SnS 2 /WSe 2 roll-ups with alternating monolayers of WSe 2 and SnS 2 , thus forming high-order SnS 2 /WSe 2 vdW superlattices. The formation of these superlattices modulates the electronic band structure and the dimensionality, resulting in a transition of the transport characteristics from semiconducting to metallic, from 2D to one-dimensional (1D), with an angle-dependent linear magnetoresistance. This strategy can be extended to create diverse 2D/2D vdW superlattices, more complex 2D/2D/2D vdW superlattices, and beyond-2D materials, including three-dimensional (3D) thin-film materials and 1D nanowires, to generate mixed-dimensional vdW superlattices, such as 3D/2D, 3D/2D/2D, 1D/2D and 1D/3D/2D vdW superlattices. This study demonstrates a general approach to producing high-order vdW superlattices with widely variable material compositions, dimensions, chirality and topology, and defines a rich material platform for both fundamental studies and technological applications.

This work involved the simulation of both a multiphase gas-liquid flow and the electromagnetic field representing a two-electrode capacitance sensor in a circular pipe. The simulation investigates in particular the sensitivity of the sensor orientation around the pipe (i.e., top-to-bottom or side-to-side) that best capture the induced flow patterns. The presented numerical work is a simplified simulation by COMSOL multi-physics which was validated by a systematic and an extensive experimental work, using (a) a specially designed simple capacitance sensor (i.e., concave two electrodes), (b) different gas-liquid superficial velocity combinations, (c) different flow section inclinations, and (d) high-speed camera images. The numerical modelling capacitance values were validated against the experimentally measured values which shows a satisfactory level of agreement with a deviation of less than ±2%. The quantity of finite points was between 280,000 and 340,000, which was influenced by the simulated flow pattern. The simulated cases captured the generated flow patterns and their variation inside the pipe, which was in a good agreement when compared to the experimental work as time-dependent values. It was found that the best orientation for the utilized two-electrode capacitance sensor was the top-to-bottom configuration. This is because the sensor's electrical field distribution was more sensitive, and capable of detecting a greater range of capacitance values. The sensitivity of the top-to-bottom configuration was 1.25-1.64 times greater than that of the side-to-side configuration. Therefore, for design purposes and performance optimization, it is recommended to use the top-to-bottom configuration.

The current study is motivated by the strict environmental regulations regarding the utilization and consumption of ecofriendly materials. In this context, the aim of this study has been to prepare and characterize different date palm tree (Phoenix dactylifera L.) fibers processed through the conventional water retting method. The chemical, elemental, crystallinity, thermal and morphological characterization of trunk (DPTRF), leaf stalk (DPLST), sheath or leaf sheath (DPLSH) and fruit bunch stalk (DPFBS) fibers was carried out. Chemical analysis revealed that the four types of date palm fibers display noteworthy differences in the content of cellulose, hemicellulose and lignin. Also, the amount of calcium is relatively high in all the date palm fibers; besides this, DPTRF exhibited 69.2% crystallinity, which is lower than that of DPLSH with 72.4% crystallinity. Moreover, DPLST and DPFBS fibers are more thermally stable (higher thermal degradation temperature) than DPTRF and DPLSH samples. Morphological analysis revealed that the fracture surface of DPFBS was relatively rougher, which would probably lead to increased bonding strength with polymers in composites. Overall, we conclude that DPFBS would be promising alternative sustainable and biomass material for the isolation of respective cellulose nanofibers and cellulose nanocrystals as potential reinforcement in polymer composites., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: S100 proteins have been implicated in various aspects of cancer, including epithelial-mesenchymal transitions (EMT), invasion and metastasis, and also in inflammatory disorders. Here we examined the impact of individual members of this family on the invasion of pancreatic ductal adenocarcinoma (PDAC) cells, and their regulation by EMT and inflammation., Methods: Invasion of PDAC cells was analysed in zebrafish embryo xenografts and in transwell invasion assays. Expression and regulation of S100 proteins was studied in vitro by immunoblotting, quantitative PCR and immunofluorescence, and in pancreatic lesions by immunohistochemistry., Results: Whereas the expression of most S100 proteins is characteristic for epithelial PDAC cell lines, S100A4 and S100A6 are strongly expressed in mesenchymal cells and upregulated by ZEB1. S100A4/A6 and epithelial protein S100A14 respectively promote and represses cell invasion. IL-6/11-STAT3 pathway stimulates expression of most S100 proteins. ZEB1 synergises with IL-6/11-STAT3 to upregulate S100A4/A6, but nullifies the effect of inflammation on S100A14 expression., Conclusion: EMT/ZEB1 and IL-6/11-STAT3 signalling act independently and congregate to establish the expression pattern of S100 proteins, which drives invasion. Although ZEB1 regulates expression of S100 family members, these effects are masked by IL-6/11-STAT3 signalling, and S100 proteins cannot be considered as bona fide EMT markers in PDAC.

Rhodamine B based fluorescence thermometry is commonly used in microfluidics to measure fluid temperatures in microchannels. Notable absorption of Rhodamine B into PDMS channel walls, however, causes difficulties in obtaining accurate temperature measurements due to a steady increase in the overall fluorescent signal. A simple and effective technique is reported that removes the fluorescent signal from absorbed Rhodamine B dye by means of photobleaching with a high intensity light source before taking images for thermometry analysis. The temperature field at the convergence of hot and cold streams in a Y-channel fabricated in PDMS/glass microfluidic chip is studied to demonstrate the execution of the photobleaching technique.