Saudi Arabia and its Gulf Co-operation Council neighbours : a study in international boundary management.

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Design principles for thermally comfortable and low energy homes in the extreme hot-humid climatic Gulf region, with reference to Dammam, Saudi Arabia

Indoor thermal comfort and its consequent energy consumption, are an increasingly important area of consideration in both developed and developing countries. The Gulf States, characterised by their composite extreme hot-humid climate and Airconditioning dependent society are renowned for their high energy consumption. The main aim of this research is to review and report on ways to enhance occupant thermal comfort in homes through improved building and system design and use that minimises energy consumption possible, in the extreme climate of Dammam, Saudi Arabia. The thesis does this by measuring and analysing the thermal performance of the buildings, the thermal satisfaction and comfort responses of their occupants and the energy consumption in them during August 2013 for the summer period and January 2014 for the winter period of the study. The comfort of occupants was assessed using the adaptive thermal comfort method. Neutral indoor air temperatures were, in several homes, surprisingly high. Moreover, most of the studied dwellings do not represent thermally comfortable homes as defined within either PMV or adaptive comfort limits. The study went on to review a broad range of factors that might strongly influence neutral temperatures indoors including the properties of the dwellings, occupant behaviours and attitudes towards high energy demand, loads and costs. The findings are discussed and conclusions drawn on individual design features that contribute to the comfort or discomfort experienced by occupants. It was found that lifestyle, attitudes and other socio-cultural factors have a clear influence on the comfort and in turn energy use in individual dwellings. Although several respondents did not sincerely care about the electricity as it is cheap, in late 2015 the Saudi government hiked the price of domestic energy bills by 60% as a result of low oil prices, putting pressure on many ordinary families to take more notice of their day to day living expenses. The recent electricity price hike provides an economic impetus for the design guidance proffered in the conclusions of this thesis to be taken seriously by householders and implemented by both them and regulating authorities in order to enhance domestic buildings and in turn reduce the CO2 emissions to the global atmosphere. The conclusion of this study is broadly applicable to other regions with similar climatic conditions and cultural contexts such as the Gulf countries

Exploring the Role of Technology in Formative Assessment in an International Baccalaureate Secondary School: Perspectives of Students and Teachers

Although technology has been available in secondary school teaching and learning practices for some time, research suggests that teachers and students in some contexts have been slow to adopt and integrate technology in formative assessment and feedback processes. This presents a challenge to advancing pedagogy in the 21st century, since the use of technology in formative assessment and feedback by teachers during the learning process is increasingly regarded as instrumental in achieving improved outcomes for students. This study used a conceptual framework that blended affordance theory, the Technology Acceptance Model from information systems research, and constructivism as learning to explore this problem and the intersection between formative assessment and technologies to reveal students' and teachers' corresponding attitudes, perceptions, use and utilisation. A mixed methods research design comprised surveys, observations, and semi-structured interviews in a London, UK secondary school context. The study highlights changes and limitations in technological affordances and the amount of teacher and student involvement and autonomy arising from their utilisation. The study found disparities and variability in the utilisation and perception of technology-assisted formative assessment and feedback among participants and discipline groups. These disparities diminished the efficacy of the teachers in measuring student progress and evaluating teaching methods using the technology, while concurrently presenting obstacles to students gaining the support they require. Therefore, the study recommends that developers focus on subject-specialist pedagogy-based and teacher-led software, while continually updating and supporting technology systems integration with teaching and assessment. Moreover, teachers should receive discipline-appropriate technology-aided formative assessment and feedback training, and students should have a technological framework to guide them in receiving and responding to teachers’ formative assessment and feedback practices. Such a holistic application should be the next aim for more effectively integrating technology in the International Baccalaureate school education system

Maximum Likelihood Estimation in the Inverse Weibull Distribution with Type II Censored Data

We consider maximum likelihood estimation for the parameters and certain functions of the parameters in the Inverse Weibull (IW) distribution based on type II censored data. The functions under consideration are the Mean Residual Life (MRL), which is very important in reliability studies, and Tail Value at Risk (TVaR), which is an important measure of risk in actuarial studies. We investigated the performance of the MLE of the parameters and derived functions under various experimental conditions using simulation techniques. The performance criteria are the bias and the mean squared error of the estimators. Recommendations on the use of the MLE in this model are given. We found that the parameter estimators are almost unbiased, while the MRL and TVaR estimators are asymptotically unbiased. Moreover, the mean squared error of all estimators decreased for larger sample sizes and it increased when the censoring proportion is increased for a fixed sample size. The conclusion is that the maximum likelihood method of estimation works well for the parameters and the derived functions of the parameter like the MRL and TVaR. Two examples on a real data set are presented to illustrate the application of the methods used in this paper. The first one is on survival time of pigs while the other is on fire losses.The authors would like to thank the referees for their suggestions and thoughtful comments that resulted in a much-improved version of the paper. This research was supported by a grant from the Office of Research Support at Qatar University, Grant no. QUST-1-CAS-2022-318

The Effect of Symptoms on the Survival Time of Coronavirus Patients in the Sudanese Population

The COVID-19 pandemic has rapidly spread worldwide, resulting in substantial rates of illness and death. Gaining insight into the various factors that impact the duration of survival among individuals diagnosed with COVID-19 is of utmost importance to inform clinical practices and public health strategies This study aims to evaluate the relationship between the acuteness of symptoms and the survival time of coronavirus patients in Sudan. The Kaplan-Meier curves and log-rank test were used to determine the symptom pattern. The results of COVID-19 and Cox regression were utilized to determine the most critical symptoms affecting coronavirus patients. The log-rank test revealed that there are differences in the pattern of age and symptoms among coronavirus patients. Cox regression revealed that symptoms affect on the survival time of coronavirus patients. The Cox proportional Hazard Model shows that the hazard of age at any time increases by 116.5%, diarrhea increases by 9%, headache increases by 62.0%, fatigability increases by 13.3%, and other symptoms increase by 47.3%. This study differs from prior studies in several ways. No current study in Sudan has used survival analysis to discover the most relevant symptoms affecting survival time

MRI Contrast Agents: Developments, Challenges, and Future Trends

Contrast agents in medicine are chemical materials used to improve tissue and fluid contrast in the body during medical imaging. It is mainly used in improving the visibility of blood vessels and the gastrointestinal tract. Some types of contrast materials are used in a medical imaging examination and can be classified according to the imaging technique used. The first contract agent dates back to 1988 which is called gadopentetate dimeglumine (Magnevist®) and was allocated for Magnetic Resonance Imaging (MRI). Then, I has become available in clinical use. Afterwards, many studies have examined the capability of MRI contrast agents to be used in diagnostic imaging in all parts of the body including the skin, the central nervous system, heart and circulation, breast, lungs, musculoskeletal and lymphatic systems, and even the gastrointestinal tract. Nowadays, MRI contrast agents are widely used in clinical practice and have expanded beyond the imitational expectations to be a key tool in disease diagnosis around the world. Contrast-Enhanced (CE) MRI keeps in development and new technologies have emerged and new agents were introduced, with great opportunity being provided to ensure better imaging and patient management practices. Also, new clinical challenges were associated with the progress in CE-MRI. This paper aims to overview the historical development of MRI and contrast materials in order to shed light on the clinical development of CE-MRI. Also, the paper overviews the contemporary perspectives and clinical challenges associated with CE-MRI with the provision of significant future trends

Crystal structures of 4-phenylpiperazin-1-ium 6-chloro-5-ethyl-2,4-dioxopyrimidin-1-ide and 4-phenylpiperazin-1-ium 6-chloro-5-isopropyl-2,4-dioxopyrimidin-1-ide

The title molecular salts, C10H15N2+·C6H6ClN2O2−, (I), and C10H15N2+·C7H8ClN2O2−, (II), consist of 4-phenylpiperazin-1-ium cations with a 6-chloro-5-ethyl-2,4-dioxopyrimidin-1-ide anion in (I) and a 6-chloro-5-isopropyl-2,4-dioxopyrimidin-1-ide anion in (II). Salt (I) crystallizes with two independent cations and anions in the asymmetric unit. In the crystal structures of both salts, the ions are linked via N—H...O and N—H...N hydrogen bonds, forming sheets which are parallel to (100) in (I) and to (001) in (II). In (I), the sheets are linked via C—H...Cl hydrogen bonds, forming a three-dimensional framework

Study of lipid profiles high and normal body mass index in polycystic ovary syndrome women in Aljouf, Saudi Arabia

Background: For women of reproductive age, polycystic ovary syndrome (PCOS) is the most prevalent endocrinological condition. Hyperandrogenism, persistent ovulatory dysfunction, obesity, and insulin resistance have all been associated with PCOS. However, recently PCOS is detected in high-body weight and normal-body-weight women. No information was available to evaluate specific lipid profiles. The goal of this study is to analyze the lipid profiles of women with polycystic ovarian syndrome who have high or normal body weight. Methods: This polycystic ovarian syndrome (PCOS) retrospective study was carried out between January 2021 and January 2022 at Sakaka’s Maternity and Children Hospital (MCH), Aljouf, Saudi Arabia. A total of 68 PCOS women were included in the study; we divided them into high (n=34) and normal body weight (n=34) according to the calculation of BMI. We obtain the test results of lipid profiles and demographic data from hospital record files. Results: We noticed changes but no significance in our research of lipid profiles in high and normal PCOS participants. The CHOL, TG, HDL, and LDL, 159.30±4.193, 97.89±7.140, 60.91±9.564, and 99.47±9.22 shown in the high BMI PCOS women respectively. While, 129.28±3.702, 83.69±4.49, 46.84±1.68 and86.53±4.36 were detected in normal BMI PCOS women respectively. There were none that were statistically significant, with the exception of cholesterol p=0.001. Conclusions: Our results show that POCS women with normal body weight and PCOS women with high BMI have different changes in their lipid profiles, but no significance has been found other than higher cholesterol levels. Therefore, losing weight can stop lipid profiles from altering, which may reduce difficulties in the future

Progressive Collapse Resistance of RC Beam–Slab Substructures Made with Rubberized Concrete

Abnormal loads can produce localized damage that can eventually cause progressive collapse of the whole reinforced concrete (RC) structure. This might have devastating financial repercussions and cause numerous severe casualties. Numerical simulation, using the finite element method (FEM), of the consequences of abnormal loads on buildings is thus required to avoid the significant expenses associated with testing full-scale buildings and to save time. In this paper, FEM simulations, using ABAQUS software, were employed to investigate the progressive collapse resistance of the full-scale three-dimensional (3D) beam–slab substructures, considering two concrete mixes, namely: normal concrete (NC) and rubberized concrete (RuC) which was made by incorporating crumb rubber at 20% by volume replacement for sand. The FEM accuracy and dependability were validated using available experimental test results. Concrete and steel material non-linearity were considered in the FE modelling. The numerical study is extended to include eight new models with various specifics (a set of parameters) for further understanding of progressive collapse. Results showed that slabs contribute more than a third of the load resistance, which also significantly improves the building’s progressive collapse resistance. Moreover, the performance of the RuC specimens was excellent in the catenary stage, which develops additional resilience to significant deformation to prevent or even mitigate progressive collapse

Thermoregulatory and Physiological Responses of Najdi Sheep Exposed to Environmental Heat Load Prevailing in Saudi Arabia

The objective of this study was to evaluate the thermoregulatory and physiological responses of Najdi rams raised under hot summer conditions prevailing in Kingdom Saudi Arabia. The core temperature (Tcore) showed circadian rhythm characterized by biphasic achrophases, which were associated with the feeding times during both seasons. Average daily Tcore was significantly (P<0.05) higher under hot summer conditions. However, the amplitudes of the rhythmic oscillation during winter and summer seasons were 0.85 and 0.56C, respectively. Rectal (Tre) and skin temperatures (Tsk) were significantly (P<0.05) higher under hot summer conditions and exhibited similar patterns during both seasons concurrent with the pattern of temperature humidity index (THI), reaching the maximum values late in the afternoon and the minimum values early in the morning. Respiratory rate (RR) and heart rate (HR) showed the same pattern of the thermal parameters and were significantly (P<0.05) higher under hot summer conditions. Serum concentrations of total protein, globulin, glucose, sodium and chloride were significantly (P<0.05) increased while those of albumin and calcium were decreased under hot summer conditions. The results obtained from this study indicate that hot summer conditions of Saudi Arabia is thermally stressful to Najdi rams. Therefore, Najdi sheep production under such conditions would require environmental and/or nutritional modification to alleviate the impact of heat stress