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Abstract The total and differential cross sections of the elastic proton–neutron and antiproton–neutron scattering are studied in a holographic QCD model, focusing on the Regge regime. Taking into account the Pomeron and Reggeon exchange, which are described by the Reggeized spin-2 glueball and vector meson propagator respectively, those cross sections are obtained. It is presented that the currently available experimental data of the total cross sections can be well described within the model. Once a single adjustable parameter is determined with the total cross section data, the differential cross sections can be calculated without any additional parameters. Although the available differential cross section data are limited, it is found that our predictions are consistent with those.

Natural fiber-based composites are essential for the environment in this era of depletion of petroleum resources and for new green environmental rules, as they have limited detrimental behavior or response against the environment. In this paper, firstly, the suitability of replacing glass fiber with natural bamboo fiber in a flax/glass/epoxy hybrid composite under a fixed bending load is investigated using Finite Element Analysis (FEA) software ABAQUS with proper model validation. Finally, five different lay-up sequences of flax/bamboo/epoxy hybrid composite laminate for fixed volume fractions of flax and bamboo strips are investigated numerically to develop design strategies for binary hybrid composite. It is found that the bending stiffness and equivalent modulus of elasticity for model FB-1 are increased by 37.53 % and 37.52 % respectively compared to the base model while the energy absorption for model FB-3 is highest which is 105.89 % higher than the base model. Analysis of various lay-up sequences showed that flexural behavior can be improved by fabricating binary hybrid composites using the concept of a sandwich structure. It is shown that all highly stiff laminas should be placed on the outer sides of the composite to achieve the maximum bending stiffness whereas they should be placed at the center to attain the maximum energy absorption.

Aluminum is widely used in industries such as automobile and aerospace due to its lightweight, but its pure form lacks sufficient strength and the properties of aluminum can be modified by adding alloying elements. This paper presents the effect of adding Magnesium (Mg), Copper (Cu), and Zinc (Zn) on the mechanical, microstructural, heat treatment properties, and corrosion behavior of aluminum-based alloys. The aluminum-based alloys were manufactured with varying percentages (1 %, 3 %, 5 %, 8 %, and 10 %) of the three alloying elements using sand casting. Tension, compression, Brinell hardness, and corrosion tests were conducted to examine the effect of these alloying elements on the alloys' properties. The tensile strength is improved significantly with the increase in alloying elements for all alloys but the compressive strength and hardness are improved for Al–Cu alloy only. After heat treatment, the hardness of Al–Mg alloy increased at 8 % and 10 % Mg content while the hardness of Al–Cu alloy decreased after heat treatment for all concentrations of Cu. The hardness of Al–Zn alloys remained unaffected by the heat treatment process. The corrosion rate is minimum for Al–Mg and it is maximum for Al–Cu alloys but at 10 % concentrations, the corrosion rate of Al–Mg alloy is higher than Al–Cu alloy. The microstructural observation before and after heat treatment revealed that the grain refinement occurred for Al–Mg and Al–Cu alloys but the microstructure remained unaffected for Al–Zn alloys. The outcomes of this study offer valuable insights into customizing the mechanical characteristics of aluminum-based alloys to suit particular applications.

Printed circuit board (PCB) is the most important part of any electronic device which is made of copper-clad laminate and glass fiber-reinforced composites. Since the ply orientation of fiber-reinforced composites and lamina thickness have a significant influence on the mechanical properties of the whole composite laminate it is necessary to investigate the effects of ply orientation and lamina thickness on the bending properties of PCB so that they can be manufactured to meet the service requirements. In this work, the bending properties of PCB were investigated for seven different ply orientations of glass fiber-reinforced composite laminas and for eight different thickness combinations (for a constant laminate thickness) of glass fiber-reinforced composite lamina and copper-clad laminate. A commercially available finite element analysis software (Abaqus) was used to simulate a three-point bending test of PCBs and the simulation results were validated using experimental results. It is found that the bending stiffness is maximum for the cross-ply laminate. The introduction of angle ply improves the maximum von-Mises stress of the PCB with an insignificant cost of bending stiffness (less than 5% reduction). It is found that the bending stiffness and the maximum von-Mises stress of the PCB can be regulated through the variation of thickness of the constituent lamina. The laminate stiffness can be increased by increasing the thickness of stiffer laminas or by placing the stiffer laminas towards the surface of the laminate. The outcome of this research would provide a comprehensive understanding of the bending characteristics of the multi-layered PCBs which can be directly utilized by the PCB manufacturers. However, the effects of ply orientation and lamina thickness variation on the behavior of the PCBs subject to temperature variation, impact loading, vibration, and other conditions that might affect the service life of the PCBs should be investigated.

Background and Objectives: Statistics are of paramount significance to physicians as they allow them to critically interpret the medical literature and to contribute to it. However, teaching statistics to medical students and physicians, as well as learning statistics, is nothing short of difficult and anxiety-inducing to a great extent. Materials and Methods: In this study, an example of a novel approach to teaching statistics to medical students is introduced at a single college of medicine in Saudi Arabia. In this retrospective report, a new approach that has been developed and delivered to students is described. Results: The approach, referred to as the personal experience pathway, is part of a major curriculum change to the MBBS program. The track presents statistics to students as a tool, rather than a subject, that students will need to interpret results, either present in the literature or those of the research projects they are conducting. The outcome of this process has been assessed through measuring students' scholarly output through student self-reporting and has been followed up over four student cohorts graduating between the years 2019 and 2022. The approach has successfully equipped students with a solid foundation of statistical understanding that has allowed them to publish in peer-reviewed journals. Such scholarly output has increased significantly over the last two years. Conclusions: The current study presents a framework through which the detailed curriculum plan could be applied to other medical schools, nationally and internationally, which will better prepare future statistically oriented physicians. [ABSTRACT FROM AUTHOR]

Since the beginning of the COVID-19 pandemic, scientists have struggled significantly to understand the complexity of COVID-19 pathophysiology. COVID-19 has demonstrated a notoriously unpredictable clinical course. This unpredictability constituted a significant obstacle to clinicians in predicting the disease course among COVID-19 patients, more specifically, in predicting who would develop severe cases and possibly die from the infection. This brief report aims to assess the diagnostic value of using a complete blood count (CBC) and applying high-dimensional analysis, i.e., principal component analysis (PCA), on it to differentiate between patients with mild and severe COVID-19 infection. The data of 855 patients were retrieved from multiple centres in Saudi Arabia. Descriptive statistics, such as counts, percentages, and medians (interquartile ranges) were used to describe patients' characteristics and CBC parameters. Analytical statistics, such as the Mann–Whitney U test, were used to compare between survivors and non-survivors. PCA was applied using the CBC parameters, and the results were compared between survivors and non-survivors. Patients in this study had a median age of 41, with an almost equal ratio of men to women. Most participants were Saudis, and non-survivors were 13.22% of the total cohort. The median values of all CBC indices were within reference ranges; however, some statistically significant differences were observed between survivors and non-survivors. Non-survivors had lower hemoglobin levels and lower hematocrit, lymphocyte, and eosinophil counts but higher WBC and neutrophil counts compared to survivors. PCA on the CBC results of survivors yielded a significantly different profile than non-survivors, indicating the possibility of its use in the context of COVID-19. The diagnostic value of CBC in the clinical management of COVID-19 should be utilized in clinical guidelines for managing COVID-19 cases. [ABSTRACT FROM AUTHOR]

Background: Diabetes is a chronic condition that may become dangerous if there is insufficient insulin to help the body function properly. The proper care for diabetes depends on how well patients observe guidelines and prescriptions; consequently, patient education is critical. Poor learning may cause bad treatment and complications or other problems related to the disease. Objectives: This study aims to evaluate patients' knowledge of diabetes, assigning a knowledge (K) score out of 100, and investigate the possible impact of educating patients, through general means or via healthcare professionals, on patient knowledge of diabetes control demonstrated in the absence/presence of diabetic complications. Methods: This multi-center interview-based cross-sectional study used a questionnaire in Madinah, Saudi Arabia. This study was conducted on adults with diabetes who were aged 15–80. We used the Michigan Diabetic Knowledge Test (MDKT) to assess the knowledge of patients with diabetes. Results: This study included 364 participants. The gender distribution was 48.33% male and 51.67% female. Most of them had type 2 diabetes (T2DM) without insulin (48.63%), followed by those with T2DM on insulin (36.26%), and patients with type 1 diabetes (T1DM) (15.11%). Patients with T2DM had significantly higher K scores than patients with type 1. Additionally, T2DM non-insulin patients' k-scores significantly exceeded those with T1DM. General and healthcare education both helped increase patients' K-scores. Mostly, patients with diabetes without any complications had significantly higher knowledge compared to those having them. Lastly, regardless of whether the education was delivered by general or professional means, the effect on glycated hemoglobin (HbA1C) levels was not significant. Conclusions: Our study revealed that patients with T2DM exhibited higher knowledge than patients with T1DM. Furthermore, receiving education, whether by a healthcare professional or by general means, improved the knowledge levels of patients with T2DM but not patients with T1DM. Regarding diabetes complications, it was found that those with a higher level of knowledge had fewer complications. However, no evidence receiving education influenced the levels of HbA1C, neither in patients with T1DM nor T2DM. [ABSTRACT FROM AUTHOR]

Although the field of classroom learning environments has undergone remarkable expansion and internationalisation, no study in Afghanistan in any subject area or at any educational level has ever adopted a learning environment framework or involved the assessment and investigation of classroom environments. Our study in Afghanistan included seven learning environment scales from the widely-used What Is Happening In this Class? (WIHIC) questionnaire, together with two scales assessing the student attitudes of Enjoyment and Self-regulation. After minor modifications to suit the Afghani context, scales were translated into Dari (one of the two dominant languages in Afghanistan) and then independently back-translated to check the accuracy of the original translation. Analyses of data from 1619 grade 10-12 science students supported the validity and reliability of the Dari-language scales. Past research in other countries was replicated in Afghanistan in that positive and statistically-significant associations were found between the learning environment and student attitudes. Some consistent patterns of gender differences and school-location differences (urban/rural) were identified.

COVID-19 has been notoriously unpredictable in its clinical course. Such unpredictability poses a challenge to clinicians in predicting patients who will develop severe cases and possibly die from the infection. This study aims to assess and compare the diagnostic value of the NLR and SII as biomarkers in predicting COVID-19 severity, represented by mortality, with a multicentre comparative study including 855 patients in Saudi Arabia. Descriptive and analytical statistics were used to compare haematological indices between survivors and non-survivors. The median age of patients included was 41 years old, with an almost equal ratio of men to women. Most participants were Saudis, and the mortality rate in the study cohort was 13.22%. Non-survivors, as compared to survivors, were significantly older, had lower RBC counts, haemoglobin and haematocrit levels, as well as significantly higher WBC and neutrophil counts. Both the NLR and SII were capable of differentiating between survivors and non-survivors, with the latter having significantly higher values. However, the NLR was superior to the SII in such differentiation, as it had a larger area under the curve. This study further confirms the diagnostic values of the NLR and SII as biomarkers in predicting COVID-19 severity and mortality, with the NLR being more sensitive and specific. Clinical guidelines on managing COVID-19 cases should benefit from these findings by harnessing the value of the NLR in COVID-19 management. [ABSTRACT FROM AUTHOR]

In this paper an attempt has been made to investigate Afghan students’ prob­ lems and offer mental health services. For this purpose, the study used the library research. Like Afghanistan in the past four decades involved of war, so the scientific work and research have faced more challenges. Therefore, in the field of children and students according psychopathology few research has been done. Despite be­ ing problems and challenges of students in the field of education and mental health service delivery, and identifying mental health, effective work has not been done. The study found that, more than six million eligible students do not have access to education, 300 schools are closed due to insecurity, only 60 percent of teachers are relative educated graduated fourteen grade or higher than, rate of teacher to students is from 32 up to 93, and 50 percent of schools are without building. So, in the past four years more than 2000 female students have been poisoned or mass hysteria. Whereas, the 48 percent of men and 75.8 percent of women are illiterate. In this study it also found that students with learning difficulties more traumatic ex­ periences 62 percent, 67.7 percent depression, and 72.2 percent had anxiety, also shown. Beyond, dispersed reports of suicide have also been given to the effect of failing to exam. According to mental health services, in all around the country there is only one hospital with 100 beds, 16 psychological counselling centers, countable and little psychiatrists. In addition, we found, that 20 percent of mentally ill clients refer to physician, whereas 80 percent of them are going to non­physician. The purpose of this article is to review in general the educational situation of Afghan students; opportunities, possibilities, and challenges facing them. So continued to talk to psychological problems such as anxiety, depression, and trauma, which they are faced, and mental health services that are provided for them.