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The selection of suitable reference evapotranspiration (ETo) models in case of climatic data scarcity is a challenging task as it plays a pivotal role in agriculture and water resource management. Therefore, the research work deals with selecting the appropriate mass transfer reference evapotranspiration model using multi criteria decision technique (MCDM) in a semi-arid region of the southern part of Kingdom of Saudi Arabia i.e., Abha. The ten mass transfer methods with ten criteria (statistical indices) using available weather parameters from 1980 to 2018 have been illustrated in this study. Models were calibrated (1980-2006) and validated for the period (2007-2018). The objective weight was computed by criteria importance through inter criteria correlation (CRITIC) method and performance score by weighted sum model (WSM), weighted product model (WPM), weighted aggregates sum product assessment (WASPAS) and evaluation based on distance from average solution (EDAS) methods which in turn rank the evapotranspiration method. The rankings obtained from MCDM techniques were validated with ranking by GPI method using spearman ranking coefficient. The result from MCDM shows that Saif model is the best model and that also GPI yielded same result. The methodology applied in this study can be adopted in any other region which in turns proved to be beneficial for crop cultivators, crop advisors, researchers, and water resource management. [ABSTRACT FROM AUTHOR]

Reference evapotranspiration (ETo) is an important parameter for climatological, hydrological and agricultural management. The FAO56 Penman-Monteith (FAO56-PM) model is one of the most accurate models. But it needs a detailed climate dataset from weather stations. Therefore, empirical reference evapotranspiration models (ETo) that need a reduced set of climate data can become an alternative approach. In this study, nine different evapotranspiration models were calibrated for the 19782000 period and validated based on the period between 2001-2017 with respect to standard FAO56-PM method based on the real climatic data obtained from Aseer metrological department, Saudi Arabia. The ranking of all the evaluated models based on the multi-criteria decision making was done in order to get the best alternative to the FAO56-PM Model. The result showed that Mahringer and Trabert models are the most appropriate with RMSE values of 2.13 mm/day and 2.47 mm/day, respectively and the value of percent error were 77.27% and 89.43%, respectively. Moreover, the values of mean bias error were found to be -2.03 mm/day and -2.35 mm/day, respectively. The calibration and validation of different ETo equations tend to increase their performance. Thus, the validated evapotranspiration model that used less climatic parameters could predict the ETo condition accurately for any region. [ABSTRACT FROM AUTHOR]

The main aim of this research work is to assess the performance of the various mass transfer-based method with respect to standard FAO56-PM. Daily meteorological data from 1979 to 2018 has been used to compute reference evapotranspiration (ETo). The climatic data from 1979 to 2006 were used for the development of the calibrated equations and data from 2007 to 2018 were applied for validation purpose. The evaluated, calibrated and further validation of calibrated models were compared using statistical tools in order to ranked the models effectiveness using Global Performance Indicator (GPI) where higher GPI value shows better model. The models were then arranged using GPI and it was found that proposed model resulted with best GPI value of 5.02, 2.85 and 5.19 during evaluation, calibration and validation respectively followed by Albrecht model. The results of this study could be used by the water management system, crop cultivators, crop advisors, researchers from research centres. Moreover, it is beneficial for the decision maker in the vast field of agriculture, hydrology and environment. The calibration and validation of different ETo equations tend to increase their performance. Thus, the validated evapotranspiration model that used less climatic parameters can predict the ETo condition accurately for Asir region. [ABSTRACT FROM AUTHOR]

The FAO-56 Penman-Monteith model is recognized as the standard method for estimating reference evapotranspiration (ETo) which requires daily meteorological data as inputs. Among all input data, vapour pressure deficit (VPD) is one of the critical parameter that drives evapotranspiration (ETo), and is of fundamental importance in crop models. In this study effort has been made to compare six vapour pressure models during four seasons. Three vapour pressure models (Models 1–3) selected as mentioned in Irrigation and Drainage Paper-56 of the Food and Agriculture Organization (FAO-56) and Models 4-6 has been selected from literature survey. Model 1, which uses daily maximum and minimum temperature, relative humidity (RH), is the preferred method to estimate actual air pressure (AE) hence it is used as standard for comparing other models. The effectiveness of vapour pressure models were measured by statistical tools and ranked according to Global Performance Indicator (GPI) where higher value of GPI represent best model. The ranking order using GPI shows that Model 5 resulted in best estimation capability with a GPI of 2.77. Moreover, the effect of variation in wind speed on the performance of the vapour pressure models in ETo estimation is also assessed. [ABSTRACT FROM AUTHOR]

Purpose: To describe two children who developed anterior uveitis after vaccination for common childhood diseases. Methods: A retrospective study of two Saudi patients who were seen at The Eye Center, Riyadh, Saudi Arabia. Results: Aged 12 and 14, respectively, the two patients developed anterior non-granulomatous uveitis 6 and 4 weeks after having the combined vaccination for measles, mumps and rubella (MMR). No other definite cause of uveitis was detected from history or from laboratory work up. Both patients responded to traditional regimens of uveitis therapy. However, they required a treatment period of several months. Conclusion: Anterior uveitis may occur following MMR vaccination. Cases of vaccination thus require ophthalmic awareness if visual symptoms or a painful red eye develop. [ABSTRACT FROM AUTHOR]

Introduction: Human Immunodeficiency Virus infection continue to represent a global health concern influenced by various social, economic, and cultural factors. The MENA are among the top regions in the world with the fastest-growing HIV epidemic. Thus, adequate knowledge and a positive attitude of people toward HIV/AIDS are of utmost importance to prevent the spreading of the disease. Accordingly, this study aims to evaluate the knowledge and attitude of the public and healthcare population toward HIV/AIDs., Methods: A cross-sectional analysis was conducted among residents within our population from October 2018 until August 2019. An anonymous online questionnaire was used to investigate the population's demographic characteristics, HIV/AIDS-related knowledge, and attitudes toward HIV-infected patients. Participants completed a 40-item questionnaire designed to measure their knowledge and attitude toward HIV/AIDS. The data was collected via surveys, administered through electronic tablets to the participants at public places (n = 5,757) and through an online version of the questionnaire on Google Forms (n = 2500), which was sent through social media platforms. Descriptive statistics were used to analyse the data using the R-statistical software program., Results: A total of 8,257 participants were included in our analysis. Saudi Arabian citizens represented 79% of the participants, while participants from the MENA countries represented 11.7% and 3% from the other Gulf Cooperation Council countries. Fifty-nine (59%) knew that HIV is a contagious infection, and 13.8% were unaware that HIV could be transmitted sexually. A few healthcare professionals reported negative attitudes toward HIV infected patients. Many risk factors, including age, gender, nationality, and education, significantly affected the knowledge and attitude scores. In this survey, we found that social media is the primary source of participants' information., Conclusions: Overall correct knowledge score of individuals about HIV/AIDS was relatively low. This study showed that the general population was knowledgeable to a certain degree about HIV/AIDS and its modes of transmission. Nevertheless, they lack a detailed understanding of the disease's nature, modes of transmission, and existing treatment. Policymakers in the region should further eliminate social discrimination and stigma in HIV-infected patients., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Elghazaly et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Aims and Background: The main objective of this study was to determine the causes of uveitis at a referral center in Riyadh, Saudi Arabia., Methods: We carried out a retrospective review of clinical records of 200 uveitis cases referred to The Eye Center, a referral center in Riyadh, Saudi Arabia. There were 120 (60%) males and 80 (40%) females with an age range of 7 to 91 years and a mean age of 35 (SD +/- 17). Patients had complete ophthalmic and medical examinations. Laboratory studies were requested whenever indicated. Patients were followed up for a minimum of 12 months., Results: In the period 1995-2000, we encountered 200 cases of uveitis among a total of 20,191 consecutive new cases, yielding a prevalence of 1%. Acute anterior uveitis of undetermined origin was found in 58 (29%) of 200 patients. There were 13 (6.5%) cases of Behçet's disease, 7 (3.5%) of Fuchs' heterochromic iridocyclitis, 6 (3%) of sarcoidosis, and 5 (2.5%) patients had Vogt-Koyanagi-Harada syndrome (VKH). Among the infectious causes, herpetic uveitis was found in 32 (16%) patients, tuberculosis in 21 (10.5%), and toxoplasmosis in 13 (6.5%) cases. Seventeen (8.5%) cases were of miscellaneous origin and in 28 (14%) cases the etiologic diagnosis was undetermined., Conclusion: Acute anterior uveitis of undetermined origin was the most common cause of uveitis, followed by Behçet's disease. Herpetic uveitis was the most common infectious cause of uveitis. Ocular tuberculosis and toxoplasmosis were found to be common causes of infectious uveitis at this referral center in Saudi Arabia.

Objective: To evaluate the impact of Saudi national protocol on the diagnosis and management of asthma for optimizing theophylline use in children with severe asthma. To also review theophylline clearance and provide guidelines for individualization of doses., Methods: Theophylline level was estimated in blood samples of 66 children with severe asthma who were admitted to King Abdulaziz University Hospital during the period 1998-1999. The theophylline doses given to these patients was reviewed and patients were categorized into 2 groups: Group one had received doses recommended by Saudi national protocol +/- 10%, group 2 had received doses <90% of that recommended by Saudi national protocol. The distribution of theophylline levels in blood samples of each group was estimated. Theophylline steady state level was used to estimate theophylline clearance using a standard pharmacokinetic equation., Results: Out of the total samples from group one, 70% of theophylline levels were within therapeutic range, while only 10% of the total samples of group 2 were within therapeutic range. The mean theophylline clearance in children (1-8 years) was estimated as 0.092 +/- 0.023 and was found significantly higher than the mean theophylline clearance (0.069 +/- 0.014) which is observed in older children (9-13 years)., Conclusion: Saudi national protocol theophylline dose guidelines had a favorable impact on the optimization of theophylline use in children with severe asthma. Guidelines that ensure accurate adjustment of doses on individual basis in view of drug level were suggested.

Objective: To record and update the sero-epidemiological status of Hepatitis A virus in Eastern Saudi Arabia. To investigate the main viral etiology of clinical hepatitis in children and discuss the possibility of introducing a Hepatitis A virus vaccine in this Province., Methods: Examining serum specimens by Enzyme Linkage Immuno-Sorbet Assay technique for these parameters: Immunoglobulin M anti-hepatitis A virus, total immunoglobulin anti-hepatitis A virus, and in selected cases we checked for hepatitis B surface antigen and anti-hepatitis C virus. The study was carried out in the Virology Diagnostic Labs, of Dammam Regional Laboratories & Blood Bank, Dammam. A total of 12,357 serum samples were collected from 5876 healthy children, 5798 healthy adults, and 683 from clinically diagnosed hepatitis in children. The period of study was 12 years from February 1987 to January 1999., Results: Hepatitis A virus prevalence showed 3% for pre-school age, 80% in older children and 93% in adults, while total prevalence was 86%. Breaking down the prevalence among children showed 3% in the <6 years age group, 62% in the 6 - <8 years age group, 71% in the 8 - <10 years age group, 83% in the 10 - <12 years age group and 93% in the 12 - <18 years age group. While the grand total among children was 78%. The prevalence of hepatitis viruses causing clinical hepatitis in children showed: 65% for hepatis A virus, 21% for hepatitis B virus, 7% for hepatitis C virus, 2% for double infection of hepatitis B virus + hepatitis C virus and 5% for non A, non B, non C., Conclusion: Hepatitis A virus infection starts dramatically high in school-age children, and then rises gradually with an increase in age. This reflects that our region is of pattern I class. There is no difference in the prevalence due to seasons of year, climate or sex. Hepatitis A virus is the leading cause of clinical hepatitis in children, followed by hepatitis B virus and hepatitis C virus. There is a possibility of starting to introduce hepatitis A virus vaccine among pre-school age children, as well as among hepatitis A virus negative adults that live in a higher socioeconomic environment within the country, which can be considered as islands of pattern II among pattern I areas.

Objective: Alpha-thalassemia is frequently encountered in eastern Saudi Arabia. We wanted to find out laboratory based incidence and laboratory features of Hemoglobin H disease in the Dammam region., Methods: We retrospectively analyzed the results of Hemoglobin electrophoresis carried out during the last 5 years in our laboratory. Hemoglobin electrophoresis was performed on cellulose acetate, pH 8.6 using Helena or Biomidi kits. Hemoglobin S was confirmed by sickle solubility test. Variant hemoglobin if present, was confirmed by citrate agar (pH 6.0) electrophoresis. Helena rapid electrophoresis system was used for plate densitometry. The diagnosis of Hemoglobin H disease was made on the basis of the presence of Hemoglobin H on electrophoresis supplemented by demonstration of Hemoglobin H inclusions in red blood cells., Results: Fifteen thousand, four hundred and ninety two blood samples were analyzed by Hemoglobin electrophoresis. We found 100 cases of Hemoglobin H disease, only one case was non-Saudi. The age ranged between 45 days to 85 years. There were 51 females and 49 males. Children (less than 12 years) were 35 and of adults there were 65. There were 35 adult females and 30 adult males. The mean +/- standard deviation of Hemoglobin H in children was 13.54 +/- 7, in adult females the mean +/- standard deviation of Hemoglobin H was 12 +/- 5.4, and in adult males it was 11.99 +/- 6.4. The Hemoglobin H inclusions seen in red blood cells ranged from 2.6-80 in children and 10-80 in adults. The sickle cell trait was co-existent in 7 cases. Hemoglobin Bart's along with Hemoglobin H was seen in 32 cases. Hemoglobin F was present, beyond first year of life in 34 cases. The Hemoglobin A2 as measured by densitometry was significantly low in all of the 3 age groups as compared to corresponding controls. The complete blood count results were available for analysis in only 26 cases of Hb H disease. The mean +/- SD values of Hb (g/dl), Hct (ratio), MCV (fl), MCH (pg) MCHC (g/dl), RDW-SD (fl) and RDW-CV (%) in these patients (all age groups together) were 8.15 +/- 1,.278 +/-.04, 59.4 +/- 5.8, 17.65 +/- 2.1, 29.4 +/- 1.7, 37.8 +/- 8.7 and 25.1 +/- 4.6. The mean Hb, Hct, MCV, MCH and MCHC were significantly reduced in all 3 age groups as compared to corresponding controls. RBC counts and RDW-CV were elevated in Hb H disease compared to corresponding controls. The blood film showed typical red cell morphology., Conclusion: Hb H disease is not infrequently encountered in the Dammam region. This condition should be kept in mind while evaluating patients for anemia. The genetic studies to determine the exact alpha-thalassemia determinants producing Hb H disease in eastern Saudi Arabia are needed.

In a 7-year retrospective analysis (1991-97) of the records of the Department of Haematology, Regional Laboratory and Blood Bank (Dammam), 54 patients from all parts of Saudi Arabia's Eastern Province were diagnosed with hereditary coagulation factor deficiencies. The largest group of patients, 42 haemophiliacs, included 4 non-Saudi patients. There were 39 haemophilia A or factor VIII deficiency patients, 2 haemophilia B or factor IX deficiency patients and 1 combined factor VIII and V deficiency patient. There were 5 Saudi patients with probable factor XIII deficiency, and 7 patients, all but one who were Saudi, had von Willebrand disease. The distribution of haemophilia patients in Eastern Province showed some differences compared with those reported from Riyadh and from Western countries. Among Saudis in Eastern Province, the number with suspected factor XIII deficiency, although low, was higher than that reported for other regions. The number of patients with haemophilia B and von Willebrand disease was lower than expected, when compared with the number of haemophilia A cases.

The Michaelis-Menten pharmacokinetic parameters Vmax and Km were calculated for 17 epileptic Saudi patients receiving phenytoin. Their ages ranged from 2.5 to 47 years (mean 21 years) and their weight ranged from 9.5 to 80 kg (mean 53 kg). Eight were females and 9 were males. Phenytoin serum concentrations at steady-state were measured using the fluorescence polarization immunoassay. The mean (+/- s.e.m) for Vmax and Km were, respectively, 10.93 +/- 0.78 mg.kg-1.day-1 and 7.75 +/- 0.66 mg.l-1 for children and 6.91 +/- 0.4 mg.kg-1.day-1 and 6.44 +/- 1.01 mg.l-1 for adults. The derived values of Vmax and Km were used to predict the steady-state serum phenytoin concentrations following a change in dose for 7 adult patients. There was a highly significant correlation between observed and predicted steady-state concentrations (r = 0.968, p less than 0.001). Linear regression analysis of Vmax vs age revealed a significant decline in Vmax with age (r = 0.877, p less than 0.01). There is a significant increase in Vmax with weight (r = 0.816, p less than 0.01). A plot of Km vs age and weight showed a poor correlation (r = 0.302, r = 0.218, respectively) and a large amount of variability. Based on this data, the daily phenytoin doses for children and adults are 7.21 mg.kg-1 and 4.83 mg.kg-1, respectively, in order to achieve and maintain a steady-state phenytoin concentration of 15 mg.l-1.