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BACKGROUND: Urinalysis is a simple, valuable, and low-cost tool for the detection of proteinuria, a significant risk factor for renal and cardiovascular diseases. The purpose of this study was to determine the rate of proteinuria and its associated risk factors in patients attending Family Medicine Clinics in Dammam, Saudi Arabia, as no study of that nature had previously been conducted. MATERIALS AND METHODS: In this register-based cross-sectional study, data including urinary protein and other urinalysis components ordered between January 2018 and January 2020 were collected from electronic medical records. In addition, data regarding nationality, gender, age, blood pressure, body mass index, serum human chorionic gonadotropin, fasting glucose, hemoglobin A1c (HbA1c), 25-hydroxy Vitamin D level, blood urea nitrogen (BUN), uric acid, creatinine, estimated glomerular filtration rate (eGFR), and lipid profile was also obtained. Proteinuria was classified as negative if no or trace protein was present, and positive if protein was ≥1+, and was considered overt proteinuria. RESULTS: In total, results of 2942 urinalysis tests were included. The mean age of the patients was 42.4 ± 14.5 years; majority of the patients were females (62.3%) and were Saudis (68.8%). The rate of proteinuria was 4.2%. Saudi nationality, female gender, age ≥ 40 years, high systolic blood pressure, high diastolic blood pressure, fasting glucose ≥126, HbA1c ≥6.5%, BUN >20 mg/dl, creatinine >1.3 mg/dl, low eGFR <60, and high low-density lipoproteins cholesterol were significantly associated with proteinuria based on bivariate analysis. Using a logistic regression model, a statistically significant association was observed between proteinuria and advancing age, the presence of urinary casts, elevated serum creatinine level, and Saudi nationality. CONCLUSION: The only variables that were independently associated with proteinuria using the logistic regression were the presence of casts in the urine, Saudi nationality, high creatinine level, and older age. These variables should be borne in mind by treating physicians.

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Improving the predictive capability of molecular properties in ab initio simulations is essential for advanced material discovery. Despite recent progress making use of machine learning, utilizing deep neural networks to improve quantum chemistry modeling remains severely limited by the scarcity and heterogeneity of appropriate experimental data. Here we show how training a neural network to replace the exchange-correlation functional within a fully differentiable three-dimensional Kohn-Sham density functional theory framework can greatly improve simulation accuracy. Using only eight experimental data points on diatomic molecules, our trained exchange-correlation networks enable improved prediction accuracy of atomization energies across a collection of 104 molecules containing new bonds, and atoms, that are not present in the training dataset.

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The development of bright free-electron lasers (FEL) has revolutionized our ability to create and study matter in the high-energy-density (HED) regime. Current diagnostic techniques have been successful in yielding information on fundamental thermodynamic plasma properties, but provide only limited or indirect information on the detailed quantum structure of these systems, and on how it is affected by ionization dynamics. Here we show how the valence electronic structure of solid-density nickel, heated to temperatures of around 10 of eV on femtosecond timescales, can be probed by single-shot resonant inelastic x-ray scattering (RIXS) at the Linac Coherent Light Source FEL. The RIXS spectrum provides a wealth of information on the HED system that goes well beyond what can be extracted from x-ray absorption or emission spectroscopy alone, and is particularly well suited to time-resolved studies of electronic-structure dynamics.

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The free-free opacity in plasmas is fundamental to our understanding of energy transport in stellar interiors and for inertial confinement fusion research. However, theoretical predictions in the challenging dense plasma regime are conflicting and there is a dearth of accurate experimental data to allow for direct model validation. Here we present time-resolved transmission measurements in solid-density Al heated by an XUV free-electron laser. We use a novel functional optimization approach to extract the temperature-dependent absorption coefficient directly from an oversampled pool of single-shot measurements, and find a pronounced enhancement of the opacity as the plasma is heated to temperatures of order of the Fermi energy. Plasma heating and opacity enhancement are observed on ultrafast timescales, within the duration of the femtosecond XUV pulse. We attribute further rises in the opacity on ps timescales to melt and the formation of warm dense matter.

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Autonomous wheelchairs are important tools to enhance the mobility of people with disabilities. Advances in computer and wireless communication technologies have contributed to the provision of smart wheelchairs to suit the needs of the disabled person. This research paper presents the design and implementation of a voice controlled electric wheelchair. This design is based on voice recognition algorithms to classify the required commands to drive the wheelchair. An adaptive neuro-fuzzy controller has been used to generate the required real-time control signals for actuating motors of the wheelchair. This controller depends on real data received from obstacle avoidance sensors and a voice recognition classifier. The wheelchair is considered as a node in a wireless sensor network in order to track the position of the wheelchair and for supervisory control. The simulated and running experiments demonstrate that, by combining the concepts of soft-computing and mechatronics, the implemented wheelchair has become more sophisticated and gives people more mobility.

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Ag and Ni/ZnO photocatalyst nanostructures were successfully synthesized by a sol-gel method. In this work, the photocatalyst sample was systematically studied based on several factors affecting the performance of photocatalyst, which are size, morphology, band gap, textural properties and the number of active sites presence on the surface of the nanocatalyst. X-ray diffraction revealed that Ag/ZnO nanomaterials experienced multiple phases, meanwhile for Ni/ZnO the phase of nanomaterials were pure and single phase for stoichiometry less than 5%. Field emission scanning electron microscope (FESEM) showed almost all of the synthesized nanomaterials possessed a mixture of nanorods and spherical-like shape morphology. The Ag/ZnO showed high photocatalytic activity, producing at least 14th trials of nanocatalyst reusability on degradation of methyl orange under UV irradiation. Interestingly, this phenomenon was not observed in larger surface area of Ni/ZnO nanomaterials which supposedly favour photocatalytic activity, but instead producing poor photocatalytic performance. The main reasons were studied and exposed by temperature-programmed desorption of carbon dioxide (TPD-CO2) which showed that incorporation of Ag into ZnO lattice has enhanced the number of active sites on the surface of the nanocatalyst. Whereas incorporation of Ni in ZnO has lowered the number of active sites with respect to undoped ZnO. Active sites measurement is effective and significant, providing opportunities in developing an intensive study as an additional factor.

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Proton radiography is a technique in high-energy density science to diagnose magnetic and/or electric fields in a plasma by firing a proton beam and detecting its modulated intensity profile on a screen. Current approaches to retrieve the integrated field from the modulated intensity profile require the unmodulated beam intensity profile before the interaction, which is rarely available experimentally due to shot-to-shot variability. In this paper, we present a statistical method to retrieve the integrated field without needing to know the exact source profile. We apply our method to experimental data, showing the robustness of our approach. Our proposed technique allows for the retrieval not only of the path-integrated fields, but also of the statistical properties of the fields.

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BACKGROUND: Although vitamin and mineral supplements are popular in many countries, few studies have documented their use among college students. Moreover, there is not much national data on the use of supplements by Saudi medical students. The aim of this study was to determine the prevalence of the use of vitamin and mineral supplements by female medical students at Imam Abdulrahman Bin Faisal University (IAU) in Dammam, Saudi Arabia, and to identify characteristics associated with the use of supplements in this population. MATERIALS AND METHODS: For this cross-sectional study, all female medical students at IAU in Dammam, Saudi Arabia, were approached during September to November 2016. Results were presented as frequency distribution. Chi-square test and logistic regression analysis were performed to determine factors associated with supplement use; P < 0.05 was considered statistically significant. RESULTS: Completed questionnaires were returned by 474 students (response rate of 77%). The prevalence of the use of vitamin and mineral supplements was 44.6%; Vitamin D was the most commonly used supplement. Association of supplement use with a higher family income and the habit of regular exercise was statistically significant. However, this use of supplements was not significantly associated with smoking or marital status. CONCLUSION: The use of supplements, particularly Vitamin D, by female medical students was 44.6%. The highest percentage of users belonged to families with higher incomes and had the habit of exercising regularly.

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A new trend describes the development and validation of a simple, sensitive and selective kinetic spectrophotometric methods for the determination of sulfadiazine in pharmaceutical formulations has been conducted. In this paper, sulfadiazine was derivatized as a new organic compound 4(4-sulphophenylazo) pyrogallol, 4-SPAP, by coupling pyrogallol with diazotized sulfadiazine in medium of controlled pH. 4-SPAP was characterized by techniques of FT-IR, H-NMR, GC-Mass, TG and DSC thermal analysis methods. Solvatochromic behavior in solvents of various polarities was also investigated. The determination of sulfadiazine was accomplished by initial rate and fixed time methods. These methods were based on the reaction of the compound containing sulfadiazine, 4-SPAP, with Ca(II) to form colored product with a maximum absorbance at 520 nm. The two methods were adopted for constructing the calibration curves and examined for their suitability for the quantitation of sulfadiazine in pharmaceuticals. The limit of detection (LOD) and limit of quantification (LOQ) were found to be, by initial rate method, 0.35 and 1.05 µg·mL-1and that by fixed time method were found to be 0.69 and 2.07 µg·mL-1, respectively. The percent relative standard deviations (%RSD) for the results ranged from 1.04% to 1.76% and 0.85% to 1.42% for the initial rate and fixed time methods of the proposed kinetic spectrophotometric method, respectively. The existence of common excipients in the pharmaceutical formulation did not produce any significant interference. Statistical comparison was reported as indicated from the F- and t-test data of the proposed methods with that of reference method showing excellent agreement and indicating no significant difference in their accuracy and precision.

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Channeling experiments were performed at the OMEGA EP facility using relativistic intensity (>10^{18}W/cm^{2}) kilojoule laser pulses through large density scale length (∼390-570 µm) laser-produced plasmas, demonstrating the effects of the pulse's focal location and intensity as well as the plasma's temperature on the resulting channel formation. The results show deeper channeling when focused into hot plasmas and at lower densities, as expected. However, contrary to previous large-scale particle-in-cell studies, the results also indicate deeper penetration by short (10 ps), intense pulses compared to their longer-duration equivalents. This new observation has many implications for future laser-plasma research in the relativistic regime.

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AIM: In acute kidney injury (AKI), regions of the kidney are hypoxic. However, for reasons yet unknown, adaptation to hypoxia through hypoxia-inducible factor (HIF) is limited. Here, we studied miR-22, a potential HIF repressor, in normal kidneys, as well as in rhabdomyolysis-induced AKI, a condition where miR-22 is up-regulated. METHODS: AKI in mice was provoked by IM injection of glycerol. Tissue homogenates were processed to determine the levels of candidate RNAs and proteins, as well as global gene expression profiles. Reporter assays quantified in vitro miR-22 activity and its modulation by mimic or inhibitor molecules, under normoxia or hypoxia (1% O2 ) respectively. In vivo, anti-miR-22 molecules were applied to normal mice or prior to induction of AKI. Renal outcome was assessed by measuring plasma creatinine, plasma urea and the levels of the injury markers Kim-1 and Ngal. RESULTS: Renal miR-22 is inducible by hypoxia and represses hypoxia-inducible factor (HIF). Specific inhibition of miR-22 regulates 1913 gene transcripts in kidneys controls and 3386 in AKI, many of which are involved in development or carcinogenesis. Specific inhibition of miR-22 up-regulates tissue protective HIF target genes, yet renal function and injury markers are unchanged or worsened. CONCLUSIONS: miR-22 is a HIF repressor constitutively expressed in the adult kidney and up-regulated in AKI. Specific inhibition of miR-22 is efficient in vivo and profoundly affects renal gene expression in health and disease, including up-regulation of HIF. However, the net effect on rhabdomyolysis-induced AKI outcome is neutral or even negative.

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X-ray emission spectroscopy is a well-established technique used to study continuum lowering in dense plasmas. It relies on accurate atomic physics models to robustly reproduce high-resolution emission spectra, and depends on our ability to identify spectroscopic signatures such as emission lines or ionization edges of individual charge states within the plasma. Here we describe a method that forgoes these requirements, enabling the validation of different continuum lowering models based solely on the total intensity of plasma emission in systems driven by narrow-bandwidth x-ray pulses across a range of wavelengths. The method is tested on published Al spectroscopy data and applied to the new case of solid-density partially-ionized Fe plasmas, where extracting ionization edges directly is precluded by the significant overlap of emission from a wide range of charge states.

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Here we investigate, using relativistic fluid theory and Vlasov-Maxwell simulations, the local heating of a dense plasma by two crossing electron beams. Heating occurs as an instability of the electron beams drives Langmuir waves, which couple nonlinearly into damped ion-acoustic waves. Simulations show a factor 2.8 increase in electron kinetic energy with a coupling efficiency of 18%. Our results support applications to the production of warm dense matter and as a driver for inertial fusion plasmas.

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BACKGROUND: With the report of high prevalence rate of Vitamin D deficiency in the literature since the 1980s, the condition can be considered an epidemic in Saudi Arabia. However, no specific steps have been taken by the Ministry of Health to tackle the problem. Moreover, little is known about general practitioners' (GPs) knowledge, attitude, and practice (KAP) of Vitamin D supplementation for infants. OBJECTIVES: To measure the KAP of GPs, of Vitamin D supplementation for infants in Dammam, Saudi Arabia. MATERIALS AND METHODS: This was a cross-sectional study of GPs practicing in primary healthcare centers in the Dammam area of Saudi Arabia. All the 110 GPs working in primary health centers (PHCs) in Dammam were invited to participate in the study. Data was collected with the help of a self-administered questionnaire. Data was analyzed using SPSS 20.0. Statistical analysis included descriptive analysis of all the variables, expressed as the mean (standard deviation [SD]) or the median if not normally distributed. RESULTS: Ninety-three GPs working in the Dammam area participated in the study. Thirty percent had excellent knowledge of Vitamin D. Ninety two percent had a positive attitude toward Vitamin D supplementation and sixty percent regularly prescribed Vitamin D supplementation for infants. CONCLUSION: The majority of GPs had a positive attitude toward Vitamin D supplementation for infants. However, their knowledge and practice need improvement.

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AIMS: The aim was to compare Eastern, Makkah, and Asir regions in term of residents' perception of the achievement of training objectives, and to assess various rotations based on residents' perception. SETTINGS AND DESIGN: This cross-sectional study was done among family medicine residents in the Eastern, Makkah, and Asir regions. METHODOLOGY: A questionnaire was developed by the investigator and validated by two experts. All residents, except R1 residents, were included. All data were collected by the investigator by direct contact with the residents. STATISTICAL ANALYSIS USED: Cronbach's alpha, analysis of variance, t-test, and univariate regression model as appropriate, were used. RESULTS: Reliability of the questionnaire was found to be 75.4%. One hundred and seven (response rate: 83.6%) residents completed the questionnaire. There were 51 (47.7%), 27 (25.2%), and 29 (27.1%) residents in the program in the Eastern region, Makkah, and Asir, respectively. The mean age was 29.1 ± 2.5 years; half of the residents were male, most of (83.2%) were married, and more than half (54.2%) of had worked in primary health care before joining the program. Overall, 45% of the residents perceived that they had achieved the training objectives. The highest rotations as perceived by the residents were psychiatry and otolaryngology while the lowest were orthopedics and ophthalmology. There were significant differences among the study regions with regard to the rotations in family medicine, internal medicine, orthopedics, general surgery, and emergency medicine. CONCLUSIONS: Overall, a good percentage of the residents perceived that they had achieved the training objectives. The rotations differed in the studied regions. Psychiatry and otolaryngology had the highest percentage of family medicine residents who perceived that they had achieved the training objectives while lowest was in internal medicine and obstetrics and gynecology. The highest rotations as perceived by the family medicine residents were psychiatry and otolaryngology while lowest were orthopedics and ophthalmology. Sharing of experience and further studies are needed to improve the program rotations.

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The aim of this study was to determine the risk factors of skin disorders among female schoolchildren in primary and intermediate schools in Al-khobar city, Eastern Saudi Arabia. This is a cross-sectional study conducted in Al-Khobar city during the period of January to March 2003. It involved 2239 female schoolchildren randomly selected from 30 regular public and private primary and preparatory schools. A multi-stage stratified random sampling technique with proportional allocation was used. Data was collected using a pre-designed structured questionnaire and clinical examination. Dandruff was negatively associated with private schools and positively associated with age, body mass index and overcrowding. The association of atopic dermatitis with family history of atopy and bronchial asthma was documented in this study. Those who were at high risk of getting acne were schoolchildren who had more baths per week and lived in villas with a high number of rooms (in other words the high socioeconomic class). Pediculosis had a negative association with a high level of father education and high socioeconomic status and a positive association with living in a flat and the number of siblings. It was concluded that sex, socioeconomic status, family history, parents' education, home type, and overcrowding were found to be risk factors for some skin disorders. Accordingly, it is recommended that a preventive health education program for schoolchildren with different levels of skin diseases be started considering the predictive variables that increase the prevalence of these diseases.

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El propósito de este estudio fue determinar los factores de riesgo de las enfermedades dermatológicas en escolares femeninas de escuelas primarias e intermedias en la ciudad de Al-Khobar, Arabia Saudita Oriente. Se realizó un estudio transversal en la ciudad Al-Khobar durante el período de enero a marzo de 2003. se estudiaron 2239 niñas en edad escolar, seleccionadas al azar de 30 escuelas primarias y preparatorias regulares, públicas y privadas. Se utilizó una técnica de muestreo al azar, estratificada de múltiple fase, con distribución proporcional. La data se colectó mediante el uso de un cuestionario estructurado pre-diseñado y evaluación clínica. La caspa estuvo asociada negativamente con las escuelas privadas y positivamente con la edad, el índice de masa corporal y el nacimiento. Este estudio documentó la asociación de dermatitis atópica con historia familiar de atopia y asma bronquial. Las escolares que tuvieron más alto riesgo de padecer acné‚ son aquellas que tuvieron más baños por semana y que vivían en villas con un alto número de habitaciones (en otras palabras, de la clase socioeconómica alta). La pediculosis tuvo una asociación negativa con un alto nivel de educación y alto estrato socieconómico del padre y una asociación positiva con el habitar en un apartamento y el número de hermanos. Se concluye que el género, el estrato socieconómico, la historia familiar, la educación de los padres, el tipo de vivienda y el hacinamiento fueron factores de riesgo para algunos desórdenes dermatológicos. En consecuencia, se recomienda que se comience un programa de educación sanitaria preventivo para escolares con diferentes grados de enfermedades dermatológicas , considerando las variables presdecibles que incrementan la prevalencia de estas enfermedades.

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OBJECTIVE: To determine the prevalence and pattern of skin disorders among female schoolchildren in primary and intermediate schools in Al-Khobar city, Eastern Saudi Arabia. METHODS: This is a cross-sectional study conducted in Al-Khobar city, Kingdom of Saudi Arabia during the period from January-March 2003. It involved 2239 female schoolchildren randomly selected from 30 regular public and private primary and preparatory schools. We used a multi-stage stratified random sampling technique with proportional allocation. We collected data using a pre-designed structured questionnaire and clinical examination. RESULTS: The prevalence of skin diseases among female schoolchildren in Al-Khobar city was 98.6%. The most common skin disease and conditions group was the pigmentary disorders (91.6%), followed by a group of dermatitis/eczema and related conditions (26.7%), and disorders of skin appendages (25.3%). The common skin diseases and conditions in this study were melanocytic nevi (MN) (68%), post-inflammatory pigmentation (56.6%), scars (26.8%), acne (22.5%), dandruff (18.1%), pediculosis capitis (5.2%) and eczema (3.1%). Postinflammatory hyper/hypo pigmentation was more common among primary schoolchildren, whereas MN, dandruff, keratosis pilaris, acne and folliculitis were significantly more common among preparatory schoolchildren. CONCLUSION: The prevalence of skin disorders among female schoolchildren in Al-Khobar city was very high. Therefore, we recommended the introduction of a preventive health education program for schoolchildren at different levels and their families and teachers on skin diseases.

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OBJECTIVES: The aim of this study was to determine the most frequent skin disorders in obese female schoolchildren in primary and intermediate schools in the Al-Khobar area, Eastern Saudi Arabia. METHODOLOGY: This was a cross-sectional study conducted in the Al-Khobar area. It involved 2239 female schoolchildren randomly selected from 30 regular public and private primary and preparatory schools. A multi-stage stratified random sampling technique with proportional allocation was used. Data was collected using clinical examination and anthropometric measurements. RESULT: THE SKIN DISEASES THAT WERE MOST COMMON IN OBESE SCHOOLCHILDREN WERE: dandruff, acne, xerosis, acanthosis nigricans, folliculitis, alopecia, stria distensae (stretch marks) and callosity. CONCLUSIONS AND RECOMMENDATIONS: obesity is associated with specific skin disorders. Health education programs on skin diseases and obesity should be provided to all schoolchildren, their families and teachers.