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Using an aerosol–climate coupled model, this paper has investigated the changes in distributions of anthropogenic and natural particles due to 4 × CO2-induced global warming, under the low emission scenario of Representative Concentration Pathway 4.5 (RCP4.5). Special attention is paid to the seasonal variations of aerosol size modes. With rising CO2 levels, surface warming, and changes in atmospheric circulations and hydrologic cycles are found during both summer (JJA) and winter (DJF). For anthropogenic particles, changes in fine anthropogenic particulate matter (PM2.5, particles with diameters smaller than 2.5 μm) decrease over high-latitude regions and increase over the tropics in both DJF and JJA. Global mean column concentrations of PM2.5 decrease by approximately 0.19 mg m−2, and concentrations of coarse anthropogenic particles (CPM, particles with diameters larger than 2.5 μm) increase by 0.005 mg m−2 in JJA. Changes in anthropogenic particles in DJF are similar to those in JJA, but the magnitudes of maximum regional changes are much smaller than those in JJA. The coarse anthropogenic particles (CPM, particles with diameters larger than 2.5 μm) increase over northern Africa and the Arabian Peninsula during JJA, whereas changes in anthropogenic CPM during DJF are minimal. During both JJA and DJF, changes in anthropogenic CPM are about two orders of magnitude smaller than those of anthropogenic PM2.5. Enhanced wet deposition by large-scale precipitation under rising CO2-induced surface warming is the critical factor affecting changes in anthropogenic particles. For natural particles, the distribution of change in the natural PM2.5 burden is similar to that of natural CPM, but much larger than natural CPM during each season. Both natural PM2.5 and CPM burdens increase over northern Africa and the Arabian Peninsula during JJA, but decrease over most of the continental regions during DJF. Changes in surface wind speed, divergence/convergence of surface wind, and precipitation are primary reasons for the variation of natural particles. [ABSTRACT FROM AUTHOR]

The total number of discovered plant species is increasing yearly worldwide. Plant species differ from one region to another. Some of these discovered plant species are beneficial while others might be poisonous. Computer vision techniques can be an effective way to classify plant species and predict their poisonous status. However, the lack of comprehensive datasets that include not only plant images but also plant species' scientific names, description, poisonous status, and local name make the issue of poisonous plants species prediction a very challenging issue. In this paper, we propose a hybrid model relying on transformers models in conjunction with support vector machine for plant species classification and poisonous status prediction. First, six different Convolutional Neural Network (CNN) architectures are used to determine which produces the best results. Second, the features are extracted using six different CNNs and then optimized and employed to Support Vector Machine (SVM) for testing. To prove the feasibility and benefits of our proposed approach, we used a real case study namely, plant species discovered in the Arabian Peninsula. We have gathered a dataset that contains 2500 images of 50 different Arabic plant species and includes plants images, plant species scientific name, description, local name, and poisonous status. This study on the types of Arabic plants species will help in the reduction of the number of poisonous plants victims and their negative impact on the individual and society. The results of our experiments for the CNN approach in conjunction SVM are favorable where the classifier scored 0.92, 0.94, and 0.95 in accuracy, precision, and F1-Score respectively. [ABSTRACT FROM AUTHOR]

This paper presents an annotated English translation of the rite of Vespers contained in the Melkite Alexandrian Arabic Book of Hours (Horologion) found in the 13th century Christian Arabic manuscript Sinai Arabic 232. Most of the texts comprising this service have been identified from the contemporary Greek Horologion, the Constantinople Euchologion and the Coptic Agpeya. This very unusual combination is discussed. While further research on Sin. Ar. 232 and other Arabic Horologia is necessary before we may draw more definitive conclusions, enough seems clear at this point to suggest that the Egyptian Melkites originally used a Hierosolymitan type Horologion and that this, in due time, was both Alexandrinised and Byzantinised. We can therefore say that Sin. Ar. 232 is an Egyptian redaction of a Middle Byzantine Horologion with archaic Hierosolymitan features. No other Arabic Horologia have been studied to date, and no earlier Melkite or Coptic Alexandrian Horologia are known. Considerable further research on Arabic Horologia is needed. [ABSTRACT FROM AUTHOR]

The goal of the present paper is to provide a revaluation of the classification of the Bedouin dialects of Northern Arabia and the Southern Levant, based on published or publicly available data and on first-hand data recently collected amongst some Bedouin tribes in Northern Jordan. We suggest extending previous classifications that identify three types of dialects, namely A (ʿnizi), B (šammari), and C (šāwi). Although intermediary or mixed types combining šammari features with šāwi features were already noted, our data suggest that further combinations are possible, either because they had so far been unnoticed or because recent levelling and dialect mixing have blurred the boundaries between some of the varieties. [ABSTRACT FROM AUTHOR]

Coastal reclamation for residential, tourism, and commercial developments in the Arabian Peninsula and other global regions has dramatically increased in recent decades. This phenomenon is undoubtedly innovative and novel; however, it disrupts the natural balance of marine environments and degrades coastal and marine resources. Moreover, the long-term sustainability of such developments might be undermined by rising water levels, earthquakes, and the behavior of filling material and others. This paper analyzed the extent of land reclamation in the Dammam Metropolitan Area (DMA) along the eastern coast of Saudi Arabia within the last two decades and its environmental sustainability impacts. The study used satellite images to compare the coastal boundary of the study area from 2000 to 2020. The study analyzed five major reclamation projects and found that a total of 6081 hectares of land has been reclaimed from the Arabian Gulf, thereby altering the coastal profile of DMA significantly. The environmental sustainability implication of these projects includes the degradation and loss of ecosystem services and marine habitat, urban sprawl, and flood risk. Therefore, environmental regulations, such as the strict prohibition of coastal reclamation, and ecosystem-based urban planning, are needed for sustainable coastal land development. [ABSTRACT FROM AUTHOR]

Khat (Catha edulis) is a recreational, chewed herbal drug that has been used as a psychostimulant for centuries in East Africa and the Arabian Peninsula, namely in Somalia, Ethiopia, and Yemen. However, the growing worldwide availability of khat has produced widespread concern. The plant comprises a large number of active substances, among which cathinone, cathine, and norephedrine are the main constituents, which can be included in the group of sympathomimetics of natural origin. In fact, these compounds are amphetamine analogues, and, as such, they have amphetamine-like nervous system stimulant effects. Chewing the leaves gives people a sensation of well-being and increases energy, alertness, and self-confidence. The chronic use of khat is, however, associated with severe cardiac, neurological, psychological, and gastrointestinal complications. The psychological dependence and withdrawal symptoms of khat are the reasons for its prolonged use. The aim of this paper is to review current knowledge on the khat plant with toxicokinetic and toxicodynamic perspectives. Namely, this review paper addresses in vitro, in vivo, and human studies. The models used, as well as the concentrations and doses with the respective biological effects, are discussed. Additionally, the main drug interactions involved with khat are described. [ABSTRACT FROM AUTHOR]

This study addresses the imperative to comprehend gravity shifts resulting from groundwater storage (GWS) variations in the Arabian Peninsula. Despite the critical importance of water resource sustainability and its relationship with gravity, limited research emphasizes the need for expanded exploration. The investigation explores the impact of GWS extraction on the gravity field, utilizing Gravity Recovery and Climate Experiment (GRACE) and Global Land Data Assimilation System (GLDAS) data in addition to validation using the WaterGAP Global Hydrology Model (WGHM). Spanning April 2002 to June 2023, this study predicts GWS trends over the next decade using the Seasonal Autoregressive Integrated Moving Average (SARIMA) model. The comprehensive time-series analysis reveals a significant GRACE-derived groundwater storage (GWS) trend of approximately −4.90 ± 0.32 mm/year during the study period. This trend has a notable impact on the gravity anomaly (GA) values, as observed through the decomposition analysis. The projected GWS indicates a depletion rate of 14.51 km3/year over the next decade. The correlation between GWS and GA is substantial at 0.80, while the GA and rainfall correlation is negligible due to low precipitation rates. Employing multiple linear regression explains 80.61% of the variance in gravity anomaly due to GWS, precipitation, and evapotranspiration. This study investigates climate change factors—precipitation, temperature, and evapotranspiration—providing a holistic understanding of the forces shaping GWS variations. Precipitation and evapotranspiration exhibit nearly equal values, limiting GWS replenishment opportunities. This research holds significance in studying extensive GWS withdrawal in the Arabian Peninsula, particularly concerning crust mass stability. [ABSTRACT FROM AUTHOR]

The emergence of wind energy as a potential alternative to traditional sources of fuel has prompted notable research in recent years. One primary factor contributing to efficient utilization of wind energy from a wind farm is the type of turbines used. However, selection of a specific wind turbine type is a difficult task due to several criteria involved in the selection process. Important criteria include turbine's power rating, height of tower, energy output, rotor diameter, cut-in wind speed, and rated wind speed. The complexity of this selection process is further amplified by the presence of conflicts between the decision criteria. Therefore, a decision is desired that provides the best balance between all selection criteria. Considering the complexities involved in the decision-making process, this paper proposes a two-level decision turbine selection strategy based on fuzzy logic and multi-criteria decision-making (MCDM) approach. More specifically, the fuzzy arithmetic mean operator is used in the decision process. The proposed approach is applied to wind data collected from the site of Qassim, Saudi Arabia. Results indicate that the proposed approach was effective in finding the optimal turbine from a set of 20 turbines of various capacities. [ABSTRACT FROM AUTHOR]

This study analyzes high-grade carbonate rocks from several strategic deposits in the Arabian Peninsula and neighboring countries. The rocks are used locally for quicklime and dololime production in twin-shaft regenerative kilns. Stable C-O-Sr isotopes, along with chemical, mineralogical-petrographic analyses, micropaleontological investigations, cathodoluminescence microscopy, organic carbon speciation, and electron paramagnetic resonance spectroscopy, were used to trace the provenance of these rocks from economically significant non-metallic deposits. The resulting database can help identify and differentiate industrial raw materials that may appear similar chemically and/or macroscopically but have different textures/microstructures that can affect the properties of the derived burnt lime products. Various technological tests, including slaking reactivity, sticking tendency at high-temperature (i.e., 1300 °C), and physico-mechanical behavior of the lime, were performed to evaluate their suitability and predict lime performance in twin-shaft regenerative kilns. Comparison of laboratory and plant results validated the resulting database. [ABSTRACT FROM AUTHOR]

In order to prove that the Arabian Plate is a tectonically active region even in its shield areas, we obtained the attenuation structure t p * of the upper mantle beneath the Arabian Plate by applying the spectral inversion method to the newly established seismic network in Saudi Arabia operated by the Saudi Geological Survey (SGS). The data sets consisted of good quality vertical components of the teleseismic events for more than 4400 spectral ratios. The result showed significant and diverse t p * structures between the eastern and western regions of the Arabian Plate. High t p * was the predominant feature underneath the Arabian Shield (western Arabia) and low t p * within the Arabian Platform (eastern Arabia). The obtained t P * values range from −1.0 s to 1.0 s. The observed high t p * patterns followed a line from north to south through the Arabian Shield along the Red Sea margin. The high t p * distribution closely followed the volcanic region, in particular the Makka–Madina–Nafud Volcanic (MMNV) line. The maximum t p * values were observed in the southern region of the Arabian Shield, at the southern part of the Red Sea, where the African and Arabian Plates diverge. The observed high t p * will be attributed to the previously revealed low-velocity anomaly and thermal activities beneath the Arabian Shield, and it is also correlated with the topography (high elevation) in the region. [ABSTRACT FROM AUTHOR]

Energy transition in the region of the Gulf Cooperation Countries (GCC) has recently commenced and is now being implemented through large-scale renewable projects, nuclear plants, and energy efficiency measures in the built environment. This paper highlights how alternative energies are associated with non-economic factors such as prestige, modernity, and (soft or symbolic) power. It analyzes the specific ways of delivering energy diversification in the Gulf through renewable megaprojects, the reorganization of the energy sector, and the incorporation of nuclear energy as an add-on source. These decisions serve GCC states in showcasing modernity, maintaining centralized control, posturing geopolitically, and extending the rent distribution mechanisms. On one hand, the energy transition in the Gulf has been domesticated through policies and strategies suiting the political systems in the region. This can have an acceleration effect on this transition. On the other hand, the implications of the adaptation of the energy transition to the reality of the Gulf remain open. The success of this transition will depend on the ability of GCC states to ecologically modernize the Gulf societies, reduce environmental risks, and enhance GCC-wide cooperation. [ABSTRACT FROM AUTHOR]

The study improves the understanding of the basal part of the Eocene Seeb Formation of Oman, informally known as "Unit 1", in terms of microfacies, lithostratigraphy and shale migration within the context of regional tectonics. We logged four sections bed-by-bed over a distance of 8.3 km, collected samples and analyzed thin-sections as well as XRD samples. For the first time, the microfacies and stratigraphic correlation of the lowermost part of the limestone-dominated Seeb Formation were studied in detail. In the analyzed area, Unit 1 is ~20 to 40 m thick, with the thickness increasing to the SE. In the upper part of Unit 1 is a laterally continuous shale horizon. The limestones of Unit 1 contain mostly packstones and grainstones. The dominant standard microfacies types are SMF 18-FOR and SMF 16. The former is dominated by benthic foraminifera, and the latter by peloids. Both SMFs indicate restricted lagoonal conditions. Foraminifera are common in Unit 1 and indicate a middle Eocene age. Considering the abundance of encountered foraminiferal bioclasts, it appears probable that the lagoon barrier was mainly composed of foraminiferal tests. Gutter casts, slumps and debrites indicate an active, partly unstable syndepositional slope, which was likely initially created by uplift of the Saih Hatat Dome and Jabal Nakhl Subdome. Differential regional uplift due to a more pronounced overall doming in the NW (Jabal Nakhl Subdome) than in the SE (Saih Hatat Dome) explains more accommodation space and greater thickness towards the SE. For the first time, we report visco-plastic shale migration/intrusion within the Seeb Formation, related to a shale horizon of Unit 1. This shale locally migrated as indicated by (1) local thickness variations, (2) detached limestone boulders floating in the shale, (3) limestone beds that have been cut-off by the shale and (4) dragged by the shale (5) an upward shale intrusion/injection which then spread parallelly to bedding similar to a salt tongue and (6) tilting overlying limestones. We suggest that shale migration is related to post-"mid"-Eocene E-W convergence between Arabia and India and to faulting or to the second, late Paleogene/early Neogene, faulting interval of the Frontal Range Fault. The shale horizon in the upper part of Unit 1 is a marker bed, which can be correlated across the study area. [ABSTRACT FROM AUTHOR]

Fine aggregates are the main ingredients that control the success of the preparation and performance of strain-hardening cementitious composites (SHCCs). Worldwide deserts can be used as eternal sources of fine aggregates for the preparation of SHCCs. Arabian Peninsula desert sand spreads over the largest desert area in the world, covering an area of 2,300,000 km2 among the Arabian Gulf countries. White and dune desert sands were procured for use in this study. The morphological structure is important in selecting the appropriate sand for use in the preparation of SHCCs. The utilization of microfibers such as polyvinyl alcohol (PVA) has become common practice for the preparation of SHCCs. The presence of desert sand is proven to enhance the dispersibility of PVA due to its spherical structure, which alleviates the friction among the ingredients forming SHCCs. Two mechanisms are defined under the tensile force at the interface of microfibers and natural sand, namely, a strong frictional force leading to rupture or a weaker force causing pullout. The synergy between fibers and fine aggregate grains depends on their surface characteristics, which can be modified using different types of mineral admixtures. In this research, the alignment of microfibers as an indication of the quality of dispersion could be evaluated using a proposed approach based on an advanced technique of microstructural analysis. PVA dispersion and its relation to strain-hardening properties are visually correlated to the surface interaction of the mineral admixture and dune sand. The microdurability and cost effectiveness of SHCCs could be assessed using the proposed approach, as depicted by the results obtained in this research work. [ABSTRACT FROM AUTHOR]

Catha edulis Forsk., commonly known as Khat, is a stimulant plant that is chewed in the Horn of Africa and the southern regions of the Arabian Peninsula. It is often used alongside conventional drugs, but there is a lack of research on its interactions with other drugs. In this study, our aim was to investigate the possibility of an herb–drug interaction between KT extract and metformin (MT) by exploring the effect of KT on the in vivo pharmacokinetics of MT in diabetic Wistar albino rats and monitoring blood glucose levels through time intervals, comparing when MT was given alone and co-administered with KT. Rats were given 500 mg/kg of KT extract and 300 mg/kg of MT daily for 7 days. The pharmacokinetic parameters of MT were analyzed using UPLC-MS/MS. The quantification was conducted using multiple reaction monitoring (MRM) in positive ion mode. The transitions used were (m/z) 130.006→59.939 for MT and 260.125→116.018 for propranolol as an internal standard (IS). An Acquity UPLC BEH HSS T3 C18 column was used with isocratic elution, and the mobile phase was formic acid (0.1%): acetonitrile (70:30 v/v) at a flow rate of 0.25 mL/min. In addition, the study delved into the in vitro impact of KT on the CYP3A4 enzyme, seeking to identify any potential disruptions in MT's metabolism that could alter its pharmacokinetics. The effect of KT extract on CYP3A4 enzyme activity was investigated using fluorescence-based enzyme assays and a CYP3A4 Inhibitor Screening Kit. The results indicated that the combined treatment showed increased systemic exposure to MT, with Cmax and AUC levels increasing by 33.42% and 45.23%, respectively. Additionally, the combination treatment led to significantly lower fasting blood glucose (FBG) levels compared to the groups treated with MT alone. It was found that at a concentration of 500 µg/mL, the CYP3A4 enzyme activity was maximally suppressed by approximately 57%, while at 250 µg/mL, it was inhibited by almost 50%. In comparison, the standard Ketoconazole only inhibited CYP3A4 activity by approximately 58%. Therefore, the in vitro results suggest that KT extract has the potential to affect CYP3A4 activity at high doses. In conclusion, the combination treatment resulted in a significant increase in MT's blood sugar-lowering effects. Therefore, it is important to be aware of this potential interaction and to monitor blood sugar levels closely when using KT alongside MT. [ABSTRACT FROM AUTHOR]

Simple Summary: The incidence and developing status of multidrug-resistant bacteria and fungi, as well as their related mortality, is reviewed by a systematic published literature search from nine countries in the Arabian Peninsula. In order to analyse the emerging status and mortality, a total of 382 research articles were selected from a comprehensive screening of 1705 papers. More than 850 deaths reported since 2010 in the Arabian Peninsula due to the infection of multidrug-resistant bacteria and fungi. Multidrug-resistant bacteria Acinetobacter baumannii, Mycobacterium tuberculosis, Staphylococcus aureus, and fungi Candida auris are the most prevalent and causing high deaths. To control these infections and associated deaths in the Arabian Peninsula, continuous preventive measures, accurate methods for early diagnosis of infection, active surveillance, constant monitoring, developing vaccines, eradicating multidrug resistance modulators, and data sharing among countries are required. We aimed to identify the prevalence and emerging status of multidrug-resistant bacteria and fungi and their associated mortality in nine countries in the Arabian Peninsula. Original research articles and case studies regarding multidrug-resistant bacteria and fungi in the Arabian Peninsula, published during the last 10 years, were retrieved from PubMed and Scopus. A total of 382 studies were included as per the inclusion and exclusion criteria, as well as the PRISMA guidelines, from a thorough screening of 1705 articles, in order to analyse the emerging status and mortality. The emerging nature of >120 multidrug-resistant (MDR) bacteria and fungi in the Arabian Peninsula is a serious concern that requires continuous monitoring and immediate preventive measures. More than 50% (n = 453) of multidrug-resistant, microbe-associated mortality (n = 871) in the Arabian Peninsula was due to MDR Acinetobacter baumannii, Mycobacterium tuberculosis and Staphylococcus aureus infection. Overall, a 16.51% mortality was reported among MDR-infected patients in the Arabian Peninsula from the 382 articles of this registered systematic review. MDR A. baumannii (5600 isolates) prevailed in all the nine countries of the Arabian Peninsula and was one of the fastest emerging MDR bacteria with the highest mortality (n = 210). A total of 13,087 Mycobacterium tuberculosis isolates were reported in the region. Candida auris (580 strains) is the most prevalent among the MDR fungal pathogen in the Arabian Peninsula, having caused 54 mortalities. Active surveillance, constant monitoring, the development of a candidate vaccine, an early diagnosis of MDR infection, the elimination of multidrug resistance modulators and uninterrupted preventive measures with enhanced data sharing are mandatory to control MDR infection and associated diseases of the Arabian Peninsula. Accurate and rapid detection methods are needed to differentiate MDR strain from other strains of the species. This review summarises the logical relation, prevalence, emerging status and associated mortality of MDR microbes in the Arabian Peninsula. [ABSTRACT FROM AUTHOR]

In this study, we investigated HLA class I and class II allele and haplotype frequencies in Emiratis and compared them to those of Asian, Mediterranean, and Sub-Saharan African populations. Methods: Two-hundred unrelated Emirati parents of patients selected for bone marrow transplantation were genotyped for HLA class I (A, B, C) and class II (DRB1, DQB1) genes using reverse sequence specific oligonucleotide bead-based multiplexing. HLA haplotypes were assigned with certainty by segregation (pedigree) analysis, and haplotype frequencies were obtained by direct counting. HLA class I and class II frequencies in Emiratis were compared to data from other populations using standard genetic distances (SGD), Neighbor-Joining (NJ) phylogenetic dendrograms, and correspondence analysis. Results: The studied HLA loci were in Hardy–Weinberg Equilibrium. We identified 17 HLA-A, 28 HLA-B, 14 HLA-C, 13 HLA-DRB1, and 5 HLA-DQB1 alleles, of which HLA-A*02 (22.2%), -B*51 (19.5%), -C*07 (20.0%), -DRB1*03 (22.2%), and -DQB1*02 (32.8%) were the most frequent allele lineages. DRB1*03~DQB1*02 (21.2%), DRB1*16~DQB1*05 (17.3%), B*35~C*04 (11.7%), B*08~DRB1*03 (9.7%), A*02~B*51 (7.5%), and A*26~C*07~B*08~DRB1*03~DQB1*02 (4.2%) were the most frequent two- and five-locus HLA haplotypes. Correspondence analysis and dendrograms showed that Emiratis were clustered with the Arabian Peninsula populations (Saudis, Omanis and Kuwaitis), West Mediterranean populations (North Africans, Iberians) and Pakistanis, but were distant from East Mediterranean (Turks, Albanians, Greek), Levantine (Syrians, Palestinians, Lebanese), Iranian, Iraqi Kurdish, and Sub-Saharan populations. Conclusions: Emiratis were closely related to Arabian Peninsula populations, West Mediterranean populations and Pakistanis. However, the contribution of East Mediterranean, Levantine Arab, Iranian, and Sub-Saharan populations to the Emiratis' gene pool appears to be minor. [ABSTRACT FROM AUTHOR]

Camel milk is known as a source of nutritional and health supplements. It is known to be rich in peptides and functional proteins. One main issue facing it is related to its contamination, mainly with aflatoxins. The present study aimed to evaluate camel milk samples from different regions while trying to reduce its toxicity using safe approaches based on probiotic bacteria. Collected samples of camel milk were sourced from two main regions: the Arabic peninsula and North Africa. Samples were tested for their contents of aflatoxins (B1 and M1) using two techniques to ensure desired contamination levels. Additionally, feed materials used in camel foods were evaluated. Applied techniques were also tested for their validation. The antioxidant activity of camel milk samples was determined through total phenolic content and antioxidant activity assays. Two strains of probiotic bacteria (Lactobacillus acidophilus NRC06 and Lactobacillus plantarum NRC21) were investigated for their activity against toxigenic fungi. The result revealed high contamination of aflatoxin M1 for all samples investigated. Furthermore, cross-contamination with aflatoxin B1 was recorded. Investigated bacteria were recorded according to their significant inhibition zones against fungal growth (11 to 40 mm). The antagonistic impacts were between 40% and 70% against toxigenic fungi. Anti-aflatoxigenic properties of bacterial strains in liquid media were recorded according to mycelia inhibition levels between 41 to 52.83% against Aspergillus parasiticus ITEM11 with an ability to reduce aflatoxin production between 84.39% ± 2.59 and 90.4% ± 1.32 from media. Bacteria removed aflatoxins from the spiked camel milk in cases involving individual toxin contamination. [ABSTRACT FROM AUTHOR]

We present a supervised machine learning (ML) approach to improve the accuracy of the regional horizontal distribution of the aerosol optical depth (AOD) simulated by the CHIMERE chemistry transport model over North Africa and the Arabian Peninsula using Moderate Resolution Imaging Spectroradiometer (MODIS) AOD satellite observations. Our method produces daily AOD maps with enhanced precision and full spatial domain coverage, which is particularly relevant for regions with a high aerosol abundance, such as the Sahara Desert, where there is a dramatic lack of ground-based measurements for validating chemistry transport simulations. We use satellite observations and some geophysical variables to train four popular regression models, namely multiple linear regression (MLR), random forests (RF), gradient boosting (XGB), and artificial neural networks (NN). We evaluate their performances against satellite and independent ground-based AOD observations. The results indicate that all models perform similarly, with RF exhibiting fewer spatial artifacts. While the regression slightly overcorrects extreme AODs, it remarkably reduces biases and absolute errors and significantly improves linear correlations with respect to the independent observations. We analyze a case study to illustrate the importance of the geophysical input variables and demonstrate the regional significance of some of them. [ABSTRACT FROM AUTHOR]

This study evaluated the historical precipitation simulations of 49 global climate models (GCMs) of the Coupled Model Intercomparison Project Phase 6 (CMIP6) in reproducing annual and seasonal precipitation climatology, linear trends, and their spatial correlation with global SST across Africa and the Arabian Peninsula during the period of 1980–2014, using Global Precipitation Climatology Centre (GPCP) data as a reference. Taylor's diagram was used to quantify the strengths and weaknesses of the models in simulating precipitation. The CMIP6 multi-mean ensemble (MME) and the majority of the GCMs replicated the dominant features of the spatial and temporal variations reasonably well. The CMIP6 MME outperformed the majority of the individual models. The spatial variation of the CMIP6 MME closely matched the observation. The results showed that at annual and seasonal scales, the GPCP and CMIP6 MME reproduced a coherent spatial pattern in terms of the magnitude of precipitation. The humid region received >300 mm and the arid region received <50 mm across Africa and the Arabian Peninsula. The models from the same modeling centers replicated the precipitation levels across different seasons and regions. The CMIP6 MME and the majority of the individual models overestimate (underestimate) in humid (arid and semi-arid)-climate zones. The annual and pre-monsoon seasons (i.e., DJFMA) were better replicated in the CMIP6 GCMs than in the monsoon-precipitation model (MJJASON). The CMIP6 MME (GPCP) showed stronger wetting (drying) trends in the northern hemisphere. In contrast, a strong drying trend in the CMIP6 MME and a weak wetting trend in the GPCP were shown in the Southern Hemisphere. The CMIP6 MME captures the spatial pattern of linear trends better than individual models across different climate zones and regions. The relationship between precipitation and sea-surface temperature (SST) exhibited a high spatial correlation (−0.80 and 0.80) with large variability across different regions and climate zones. The GPCP (CMIP6 MME) exhibited a heterogenous (homogeneous) spatial pattern, with higher correlation coefficients recorded in the CMIP6 MME than in the GPCP in all cases. Individual models from the same modeling centers showed spatial homogeneity in correlation values. The differences exhibited by the individual GCMs highlight the significance of each model's unique dynamics and physics; however, model selection should be considered for specific applications. [ABSTRACT FROM AUTHOR]

Artemisia species are very important medicinal plants, particularly in the Middle East and in developing countries. Their products have been used in traditional and medicine contemporary for the treating of infectious ulcers, gangrenous ulcers, inflammations, and malaria. Artemisinin derived from Artemisia species has been used as a drug in many countries for malaria disease treatment. Hence, this study aimed to identify and evaluate the bioactive compounds of three species of Artemisia (Artemisia judaica, Artemisia monosperma, and Artemisia sieberi) growing in Saudi Arabia. Therefore, several analytical techniques, such as gas chromatography–mass spectrometry (GC-MS), UV-Visible spectrophotometry (UV-Vis), and high-performance liquid chromatography (HPLC), with reference standards, were used. The GC-MS analysis of the artemisia species revealed many bioactive constituents associated with plant secondary metabolites; some of these identified phytochemical components have biological activity. A. Judaica showed the highest number of bioactive compounds, followed by A. sieberi and A. monosperma. Further, the total phenol, total flavonoid, total tannin, terpenoids, and TCA were estimated. Furthermore, biomolecules such gallic acid, tannin acid, quercetin, and artemisinin in different artemisia species were quantified using HPLC with the reference standard. The amount of artemisinin in the leaf extract of these species (A. sieberi, A. Judaica, and A. monosperma) was found to be about 3.01, 2.5, and 1.9 mg/g DW, respectively. Moreover, the antioxidant activity of the samples was estimated. The obtained results have shown that these species possessed high antioxidant activity, and the scavenging of the DPPH radical and hydrogen peroxide were found to be raised with the increase in the plant extract concentration. This reflects the number of bioactive compounds in these species. The findings of this research support and justify the utilization of Artemisia species in folk medicine in the Middle East. [ABSTRACT FROM AUTHOR]

This work aimed to study the synoptic evolution and dynamics of the dust activity associated with the desert cyclone occurring over North Africa and the Arabian Peninsula on 4–8 April 2007 based on ECMWF analysis (ERA5) data. This desert cyclone formed over North Africa (Algeria) in the lee of the Atlas Mountains in response to a powerful upper-level trough transporting cold air into northern Africa coming from high latitudes. The development of the cyclone was initiated when the contrast in temperature between the Mediterranean Sea and northern Africa (the desert) was strong, which increased the meridional temperature gradient. The isobaric vorticity analysis illustrated that the strong advection of positive vorticity and warm air ahead of the cyclone triggered cyclogenesis and low-level jet (LLJ) formation. The strong LLJ maintained the development of the cyclone inside the area of baroclinicity at a low-level. The horizontal divergence of 700 hPa level covered the region downstream of the cyclone trough and is coupled with the lower-level convergence. The study of frontogentical function concluded that the first stage of cyclogenesis is associated with frontogenesis working at the initial front of the cyclone. The vertical motions are then dominated by the direct transverse circulation with the ascent of the warmer and descent of the colder air. The mass transport within the circulation causes pressure falls along the surface front connected with convergence leading to the production of vorticity. The dust emissions linked to the cyclone during its duration and along its path were also investigated. [ABSTRACT FROM AUTHOR]

Wild medicinal plants are the main source of active ingredients and provide a continuous natural source for many folk medicinal products, a role that is important for society's health with an impressive record of utilization. Thus, surveying, conserving, and precisely identifying wild medicinal plants is required. The current study aimed to precisely identify fourteen wild-sourced medicinal plants from southwest Saudi Arabia, within the Fifa mountains area located in Jazan province, using the DNA barcoding technique. Two DNA regions (nuclear ITS and chloroplast rbcL) were sequenced and analyzed for the collected species using BLAST-based and phylogeny-based identification methods. Based on our analysis, ten of the fourteen species were successfully identified by DNA barcoding, five were identified as morphologically inspected, and three were morphologically indifferent. The study was able to distinguish some key medicinal species and highlight the importance of combining morphological observation with DNA barcoding to ensure the precise identification of wild plants, especially if they are medicinally relevant and associated with public health and safety usage. [ABSTRACT FROM AUTHOR]

This research extends Hasan Fathy's (1986) principle of vernacular architecture by focusing on the Rawshan through an investigation of two criteria: aesthetics and energy efficiency. The paper discusses the views of both the Saudi public and key decision-makers on reviving vernacular architecture in the context of Saudi Arabia's rapidly developing economy, characterized by relatively high rates of energy consumption and CO2 emissions. This research explores (a) the interaction in domestic buildings of Saudi occupants with their windows, and how these are perceived as an interface with the external environment; (b) awareness and knowledge of the use of shading elements (such as Rawshans) to reduce the use of artificial lighting while maintaining indoor privacy; (c) Saudi awareness of, and familiarity with, the Rawshan as a vernacular element and a secular architectural tradition; and (d) Saudi views on the revival of traditional architectural elements with a focus on the Rawshan. An online survey (n = 812) was conducted across Saudi Arabia complemented by interviews with expert decision-makers (n = 23) to (a) assess criteria such as privacy, aesthetics, daylight, ventilation, and energy consumption in Saudi residences and (b) investigate the level of acceptance of an optimized retrofitted Rawshan design. [ABSTRACT FROM AUTHOR]

This paper examines the climate change impact on the spatiotemporal soil salinity dynamics during the last 30 years (1987–2017) in the arid landscape. The state of Kuwait, located at the northwest Arabian Peninsula, was selected as a pilot study area. To achieve this, a Landsat- Operational Land Imager (OLI) image acquired thereabouts simultaneously to a field survey was preprocessed and processed to derive a soil salinity map using a previously developed semi-empirical predictive model (SEPM). During the field survey, 100 geo-referenced soil samples were collected representing different soil salinity classes (non-saline, low, moderate, high, very high and extreme salinity). The laboratory analysis of soil samples was accomplished to measure the electrical conductivity (EC-Lab) to validate the selected and used SEPM. The results are statistically analyzed (p ˂ 0.05) to determine whether the differences are significant between the predicted salinity (EC-Predicted) and the measured ground truth (EC-Lab). Subsequently, the Landsat serial time's datasets acquired over the study area with the Thematic Mapper (TM), Enhanced Thematic Mapper Plus (ETM+) and OLI sensors during the last three decades over the intervals (1987, 1992, 1998, 2000, 2002, 2006, 2009, 2013, 2016 and 2017) were radiometrically calibrated. Likewise, the datasets were atmospherically and spectrally normalized by applying a semi-empirical line approach (SELA) based on the pseudo-invariant targets. Afterwards, a series of soil salinity maps were derived through the application of the SEPM on the images sequence. The trend of salinity changes was statistically tested according to climatic variables (temperatures and precipitations). The results revealed that the EC-Predicted validation display a best fits in comparison to the EC-Lab by indicating a good index of agreement (D = 0.84), an excellent correlation coefficient (R2 = 0.97) and low overall root mean square error (RMSE) (13%). This also demonstrates the validity of SEPM to be applicable to the other images acquired multi-temporally. For cross-calibration among the Landsat serial time's datasets, the SELA performed significantly with an RMSE ≤ ± 5% between all homologous spectral reflectances bands of the considered sensors. This accuracy is considered suitable and fits well the calibration standards of TM, ETM+ and OLI sensors for multi-temporal studies. Moreover, remarkable changes of soil salinity were observed in response to changes in climate that have warmed by more than 1.1 °C with a drastic decrease in precipitations during the last 30 years over the study area. Thus, salinized soils have expanded continuously in space and time and significantly correlated to precipitation rates (R2 = 0.73 and D = 0.85). [ABSTRACT FROM AUTHOR]

At the center of the Republic of Djibouti, an eroded rift called Asal is located where tectonic and magmatic activities can be observed at the surface. Multiple studies were carried out with different exploration methods, such as structural, geophysical and hydrogeological, to understand rifting processes and characterize the subsurface of this rift. Among these subsurface exploration methods, the deep geoelectrical structures need to be better defined with the magnetotelluric (MT) method to better delineate the deep resistivity structures. With the objective of improving our understanding of the deep rift structure, magnetotelluric (MT) data acquired in the Asal rift were analyzed and inverted to build a 2D electrical conductivity model of the hydrothermal system. To achieve this, a dimensionality analysis of the MT data along a 2D profile perpendicular to the rift axis was carried out. Results of this analysis justify the approximation of 2D conductivity structure. Then, 2D inversion models were achieved to build models of the conductive structures. Dimensionality analysis results revealed the existence of electrical anisotropy. Consistent correlation between geoelectric strike and electrical anisotropy direction was suggested. Electrical anisotropy direction determined from the ellipticity of the phase tensor for the short periods was interpreted as the consequence of tectonic activity and horizontal deformation of the rift. Moreover, electrical anisotropy direction for the long periods was assumed to be related to the effects of combined magmatic-tectonic activities with predominant magma/dyke intrusion, which implies the vertical deformation and the subsidence of the rift and may imply the alignment of Olivine. Moreover, the variation and rotation of paleo and recent stress fields direction of plate motion in Asal rift located at the junction of three diverging plates—Arabia, Nubia and Somalia—over geological time can generate both magmatic and tectonic activities which in turn can induce a preferred direction of electrical anisotropy which is the direction of the highest conductivity. While the north-south electrical anisotropy direction is parallel to the direction of Red Sea Rift propagation, the north-east electrical anisotropy direction is aligned with the extension direction between Arabia and Somalia plates. Results of the 2D inversion models presented for the Asal rift allowed to identify two superimposed conductive units close to the surface and are interpreted as a shallow aquifer and a wide potential hydrothermal system. These conductive mediums are overlying a relatively resistive medium. The latter is associated with a magmatic system likely containing hot and/or partly molten rocks. The 2D conductivity model developed in this study could be considered as conceptual model of Asal rift prior to modeling multiphase fluid flow and heat transfer and/or could be used to identify the hydrothermal system for future drilling target depth of geothermal exploration. [ABSTRACT FROM AUTHOR]

This research assessed stress regimes and fields in eastern Iran using fault-slip data and the tectonic events associated with these changes. Our stress analysis of the brittle structures in the Shekarab Mountains revealed significant changes in stress regimes from the late Cretaceous to the Quaternary. Reconstructing stress fields using the age and sense of fault movements showed that during the late Cretaceous, the direction of the maximum horizontal stress axes (σ1) under a compressional stress regime was ~N290°. This stress regime led to the uplifting of ophiolites and peridotites in eastern Iran. During the Eocene, the σ1 direction was NE-SW. The late Eocene and Oligocene stress states showed two distinct transpression and transtension stress regimes. This transition from transpression to transtension in the eastern Shekarab Mountains was the consequence of regional variations in stress regimes. The Quaternary stress state indicates that the tectonic regime in the Quaternary is strike-slip and the σ1 direction is ~N046°, which coincides with the current convergence direction of the Arabia–Eurasia plates. Our paleostress analysis revealed that four distinct stress regimes have been recognized in the area, including compressional, transtensional, transpressional, and strike-slip regimes. Our findings indicated that the diversity of the tectonic regimes was responsible for the formation of a variety of geological structures, including folds with different axes, faults with different mechanisms, and the current configuration of the Sistan suture zone. [ABSTRACT FROM AUTHOR]

The Ficus populifolia Vahl. in the Arabian Peninsula is threatened, peripheral, and geographically isolated from its main population in Africa. Here, the entire plastome of F. populifolia from the Arabian Peninsula was sequenced and analyzed to provide a baseline genetic resource for future research. The F. populifolia plastome has a classic quadripartite structure with a size of 160,610 bp, the large and small single copies of 88,729 and 20,097 bp, respectively, and each pair of inverted repeats are 25,892 bp. The genome includes 113 unique genes, 79 protein-coding genes, 30 tRNAs, and 4 rRNAs. The results reveal a total of 49 long repeats, including (30) palindromic, (14) forward, and (5) reverse repeats. Similarly, a total of 186 simple sequence repeats were identified, 83.8% of which were mononucleotides. The genomic comparison with four Ficus species indicated that the plastome of F. populifolia was highly conserved, with some hypervariable noncoding regions. The phylogenomic analysis of 28 species of Ficus, based on 78 coding genes, revealed that F. populifolia is closely related to the African species F. lyrata. The genomic data generated in this study provide valuable resources for future investigations on the population genetics, authentication, and genetic conservation of the wild Arabian population of F. populifolia. [ABSTRACT FROM AUTHOR]

Arabian Shield occupying the western part of the Arabian Peninsula is an area where strong heterogeneities in crustal structures are associated with several factors, such as an ongoing rifting process in the Red Sea basin, massive recent effusive volcanism in several large basaltic fields (harrats), as well as traces of complex tectonic evolution of this area in Precambrian due to the accretion of several terrains. Geophysical studies of the crust give important information to identify the roles of these and other factors. Receiver function is one of the most robust and relatively inexpensive tools to derive the depths of the major interfaces, of which Moho is the most important, as well as mean velocity parameters in the crust. Based on the H-k stacking method, we have determined the Moho depths and the mean Vp/Vs ratios below a number of seismic stations distributed on the Arabian Shield. As in most of previous studies, we have identified a gradual increase of the crustal thickness from 25 km in the coastal areas of the Red Sea to ~40 km in the eastern margin of the shield. The crustal thickness distribution appears to be consistent with seismic velocity anomalies derived at 30 km depth in the tomography model by (El Khrepy, 2021). For the Vp/Vs ratio, we observe strong variations over the entire study area, and in some cases even between stations located close to each other. This is especially clear in areas of recent magmatism, such as in Harrats Lunayyir and Rahat, where stations with high Vp/Vs ratios correspond to zones with fresh monogenic cones and historical magmatic activity. [ABSTRACT FROM AUTHOR]

This paper investigates the temperature and precipitation extremes over the Arabian Peninsula using data from the regional climate model RegCM4 forced by three Coupled Model Intercomparison Project Phase 5 (CMIP5) models and ERA–Interim reanalysis data. Indices of extremes are calculated using daily temperature and precipitation data at 27 meteorological stations located across Saudi Arabia in line with the suggested procedure from the Expert Team on Climate Change Detection and Indices (ETCCDI) for the present climate (1986–2005) using 1981–2000 as the reference period. The results show that RegCM4 accurately captures the main features of temperature extremes found in surface observations. The results also show that RegCM4 with the CLM land–surface scheme performs better in the simulation of precipitation and minimum temperature, while the BATS scheme is better than CLM in simulating maximum temperature. Among the three CMIP5 models, the two best performing models are found to accurately reproduce the observations in calculating the extreme indices, while the other is not so successful. The reason for the good performance by these two models is that they successfully capture the circulation patterns and the humidity fields, which in turn influence the temperature and precipitation patterns that determine the extremes over the study region. [ABSTRACT FROM AUTHOR]

Acacia ehrenbergiana (Hayne), also known as Salam, is a highly drought resistant shrub distributed in North and East Africa, and the Arabian Peninsula. The plant is gathered for its gum and fiber, and is an important legume species for indigenous populations. In this study, the phytochemical analysis, antibacterial, and antioxidant properties of various alcoholic and aqueous extracts of Acacia ehrenbergiana grown in Qatar were investigated. The qualitative phytochemical screening of this species exhibited the presence of glycosides, tannins, flavonoids, terpenoids, saponins, phenol, and anthraquinones in various extracts. The agar diffusion method was performed to check the antibacterial activity. The acetone and ethanol extracts showed 85% antibacterial activity of the control against Gram-negative E. coli, while the acetone extract had 65% activity against the Bacillus Gram-positive species. The highest activity against Staphylococcus aureus was 65% for the butanol extract. The antioxidant capacities were evaluated by the DPPH method. Various extracts exhibited antioxidant activities similar to or higher than standard antioxidants, with the highest percent inhibition of 95% for the acetone and ethanol extracts. The acetone extracts were further purified by reverse phase combiflash chromatography followed by HPLC. Three of the pure compounds isolated were subjected to MS, FTIR, and NMR spectral analysis and were found to be stigmasterol, spinasterol, and theogallin. In conclusion, the observed antibacterial and antioxidant activities as well as the presence of secondary metabolites with potential medicinal activities makes Acacia ehrenbergiana a potent valuable endemic medicinal plant. [ABSTRACT FROM AUTHOR]

Simple Summary: The poultry industry is of great importance worldwide; however, mycotoxins contamination, especially aflatoxins, has harmful effects on poultry production. Therefore, finding out new strategies to alleviate aflatoxin contamination is an important trend of research. In our study, we focused on the in ovo injection techniques using the methanolic extract of brae beery "Arctostaphylos uva-ursi" (Ar. uu) to modulate the aflatoxinB1 (AFB1) adverse effects in broiler embryos. As a result, 0.1 g of Ar. uu in ovo injection alleviates AFB1 embryotoxicity by enhancing chicks' physiological responses and optimizing antioxidant status, which is reflected in a low mortality rate and heavier relative weight of the hatched chicks. The in ovo injection of AFB1 + Ar. uu significantly declined AFB1-induced toxicity in embryos and increased broiler chicks embryo's survival by 62.5%, increased relative embryo weight by ∼65.25% compared to eggs injected with AFB1 alone. Regarding immune responses, the in ovo injection of Ar. uu enhances the embryo's humoral immune responses and regulates oxidative stress biomarkers. In general, the in ovo injection of Ar. uu modulates broiler chicks' embryotoxicity caused by AFB1. In ovo injection of nutrients can modulate the embryo's physiological responses against aflatoxin B1 (AFB1) embryotoxicity. This hypothesis was tested using in ovo injection of Arctostaphylos uva-ursi (Ar. uu.) methanolic extract. The total polyphenols, total flavonoids, total antioxidant capacity, and GC-MS analysis were all assessed in the Ar. uu. methanolic extract. A total of 180 ten-day-old embryonated eggs were distributed into six groups of 30 replicates each. The first group was used as a control (non-injected), and the second, third, fourth, fifth, and sixth groups were injected with 10 µ double-distilled water (DDW), 500 µL methanol, 0.01 g Ar. uu./500 µL methanol, 50 ng AFB1/10 µL DDW, and 50 ng AFB1 in 10 µ DDW + 0.01 g Ar. uu./500 µL methanol, respectively. The relative embryo weight, residual yolk sac weight, tibia length and weight, and survival were recorded. Total and differential leukocytes, oxidative stress, and humoral immune responses were observed. The residual yolk sac was lower (p < 0.05) in the Ar. uu. group than other groups. The embryonic growth (tibia weight and length) was enhanced in AFB1 + Ar. uu.-injected embryos compared with those injected with AFB1 alone. In conclusion, in ovo injection of Arctostaphylos uva-ursi could modulate AFB1-induced toxicity in chicken embryos. [ABSTRACT FROM AUTHOR]

Photovoltaics (PV) output power is highly sensitive to many environmental parameters and the power produced by the PV systems is significantly affected by the harsh environments. The annual PV power density of around 2000 kWh/m2 in the Arabian Peninsula is an exploitable wealth of energy source. These countries plan to increase the contribution of power from renewable energy (RE) over the years. Due to its abundance, the focus of RE is on solar energy. Evaluation and analysis of PV performance in terms of predicting the output PV power with less error demands investigation of the effects of relevant environmental parameters on its performance. In this paper, the authors have studied the effects of the relevant environmental parameters, such as irradiance, relative humidity, ambient temperature, wind speed, PV surface temperature and accumulated dust on the output power of the PV panel. Calibration of several sensors for an in-house built PV system was described. Several multiple regression models and artificial neural network (ANN)-based prediction models were trained and tested to forecast the hourly power output of the PV system. The ANN models with all the features and features selected using correlation feature selection (CFS) and relief feature selection (ReliefF) techniques were found to successfully predict PV output power with Root Mean Square Error (RMSE) of 2.1436, 6.1555, and 5.5351, respectively. Two different bias calculation techniques were used to evaluate the instances of biased prediction, which can be utilized to reduce bias to improve accuracy. The ANN model outperforms other regression models, such as a linear regression model, M5P decision tree and gaussian process regression (GPR) model. This will have a noteworthy contribution in scaling the PV deployment in countries like Qatar and increase the share of PV power in the national power production. [ABSTRACT FROM AUTHOR]

Given the current concerns about climate change, particularly, the stratospheric temperature effect on climatic surface temperature, it is of fundamental importance to investigate the impact of the lower stratospheric temperature on regional climate. This paper examines the lower stratospheric temperature (LST) at 50 hPa in the winter season and its relation to the surface air temperature (ST) over the Arabian Peninsula in the period 1951–2016. Generally, LST had an insignificant decreasing trend over the entire period, with a relatively high standard deviation of 1.3 °C. According to the coefficient of variability (COV), the fluctuation in the LST from year to year is relatively high, especially in the last reference period (1981–2010). An insignificant increasing (0.05 °C per year) trend through the period between 1951 and 1992 was observed, while an insignificant decreasing (−0.05 °C per year) trend was observed during the second period of 1993–2016. From the spectral analysis, the periodicity cycles of LST time series at periods of about 2.2, 2.54, and 13.2 years with respect to the 95% significance confidence level were found. LST may be influenced by quasi-biennial oscillation and the sunspot cycle. A strong relationship was found between LST and ST over the Arabian Peninsula. [ABSTRACT FROM AUTHOR]

The long-held tradition of wearing daggers in southern Arabia is in decline. This research examines the rich history of the southern Arabian dagger, outlining its story over time, craftsmanship, and changing use, from a weapon to a ceremonial piece. A significant contribution in the field of visual art is offered, firstly by demonstrating the beauty of this metal artwork form, and secondly by examining the notions of pride, masculinity and identity with regard to southern Arabian dagger wearing. It is argued here that men in this region continue to attach meaning to the dagger. Additionally, existing critical studies, including the various efforts being made to respect and preserve the dagger's cultural significance, are highlighted. It is contended here that for these reasons, the southern Arabian dagger will not be lost to history. [ABSTRACT FROM AUTHOR]

From 1975 to 2021, the United Arab Emirates (UAE) imported more than 1300 live Arabian oryxes (AOs) and scimitar-horned oryxes (SHOs) for conservation programs. The objective of this study was to estimate the prevalence of orbiviruses Bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) in AOs and SHOs from captive herds in the UAE. Between October 2014 and April 2015, 16 AOs and 13 SHOs originating from Texas (USA) and 195 out of about 4000 SHOs from two locations in the UAE were blood sampled to be tested by indirect enzyme-linked immunosorbent assay (ELISA) and real-time reverse transcriptase polymerase chain reaction (RT-qPCR) assays. Eight imported AOs (50% CI [24.7–75.4%]) and eight imported SHOs (61.5% CI [31.6–86.1%]) were found BTV seropositive, in contrast with three out of 195 SHOs (1.5% CI [0.3–4.4%]) from the Emirates. BTV-2 genome was detected in 6/16 of the Arabian Oryx, and amongst those, one out of six was seronegative. None of the tested samples was found positive for EHDV. Our results illustrate the wide local variation regarding BTV seroprevalence in domestic and wild ruminants in the Arabian Peninsula. These results stress the need for pre-import risk assessment when considering translocation of wild ruminant species susceptible to orbiviruses not only in the country of destination but also where transit happens. [ABSTRACT FROM AUTHOR]

The continued growth in the human population of the world will generate an increased demand for food that will be hard to meet with existing agricultural systems, as an equivalent increase in agricultural land is not available. Predicted changes in the climate will likely exacerbate the situation by increasing sea levels and the salinisation of coastal areas. Although most of our crop plants are sensitive to salinity, salt-tolerant plants, halophytes, have evolved and offer a potential as crops that can yield in saline areas or areas irrigated with saline water. We searched the literature for halophytes, identified using the database eHALOPH, native to the countries of the Gulf Cooperation Council that could be developed as crops, with the aim of attracting the attention of plant breeders, agriculturists, farmers, and others in the region to the possible uses of halophytes. Halophytic species can be grown and irrigated with brackish water where good drainage is available and used for forage or fodder, to stabilise land, and to produce biomass for fuel. In the longer-term, the cultivation of horticultural crops and those grown for nutraceuticals or pharmaceuticals is feasible. [ABSTRACT FROM AUTHOR]

Western Arabia routinely experiences geophysical phenomena that deform the surface of the earth in a variety of ways. These phenomena include earthquakes, volcanic eruptions, sinkholes, and earth fissuring and fracturing. We perform a time-series analysis of interferometric synthetic aperture radar (InSAR) observations derived from the ESA Sentinel-1 radar satellite constellation to map regional surface displacements in western Arabia as a function of time. We rely on InSAR products generated by the JPL-Caltech ARIA project to detect regions with short wavelength anomalies, and then manually reprocess InSAR products at a higher resolution for these regions to maximize spatial and temporal coverage. We post-process InSAR products using MintPy workflows to develop the InSAR time series. We report short wavelength anomalies localized within alluvial valleys across western Arabia and find a 5 cm/year line-of-sight surface displacement within the Al-Yutamah Valley. Part of the observed subsidence is correlated with surface fractures that developed in conjunction with severe rainfall events in regions characterized mainly by alluvial sediments at the surface. Regions of observed subsidence that are not associated with any surface fractures or fissures are correlated with the presence of basalt layers at the surface. Both regions are subject to groundwater exploitation. The observed subsidence is inferred to be driven by groundwater withdrawal perhaps modulated by the presence of a preexisting depositional environment (e.g., paleo-lake deposits) that promotes unconsolidated soil compaction. [ABSTRACT FROM AUTHOR]

The titania pulp—a semi product received from the industrial production of titania white—was submitted for the thermal heating at 400–600 °C under Ar and H2 to obtain TiO2 with different structure and oxygen surface defects. Heating of titania in H2 atmosphere accelerated dehydration and crystallisation of TiO2 compared to heating in Ar. TiO2 prepared at 500 and 600 °C under H2 had some oxygen vacancies and Ti3+ centres (electron traps), whereas TiO2 obtained at 450 °C under H2 exhibited some hole traps centres. The presence of oxygen vacancies induced adsorption of atmospheric CO2. It was evidenced, that ethylene reacted with TiO2 after UV irradiation. Formic acid was identified on TiO2 surface as the reaction product of ethylene oxidation. Hydroxyl radicals were involved in complete mineralisation of ethylene. TiO2 prepared at 500 °C under H2 was poorly active because some active sites for coordination of ethylene molecules were occupied by CO2. The most active samples were TiO2 with high quantity of OH terminal groups. At 50 °C, the physically adsorbed water molecules on titania surface were desorbed, and then photocatalytic decomposition of ethylene was more efficient. TiO2 with high quantity of chemisorbed OH groups was very active for ethylene decomposition. The acidic surface of TiO2 enhances its hydroxylation. Therefore, it is stated that TiO2 having acidic active sites can be an excellent photocatalyst for ethylene decomposition under UV light. [ABSTRACT FROM AUTHOR]

Human coronaviruses cause both upper and lower respiratory tract infections in humans. In 2012, a sixth human coronavirus (hCoV) was isolated from a patient presenting with severe respiratory illness. The 60-year-old man died as a result of renal and respiratory failure after admission to a hospital in Jeddah, Saudi Arabia. The aetiological agent was eventually identified as a coronavirus and designated Middle East respiratory syndrome coronavirus (MERS-CoV). MERS-CoV has now been reported in more than 27 countries across the Middle East, Europe, North Africa and Asia. As of July 2017, 2040 MERS-CoV laboratory confirmed cases, resulting in 712 deaths, were reported globally, with a majority of these cases from the Arabian Peninsula. This review summarises the current understanding of MERS-CoV, with special reference to the (i) genome structure; (ii) clinical features; (iii) diagnosis of infection; and (iv) treatment and vaccine development. [ABSTRACT FROM AUTHOR]

Euphorbia cactus Ehrenb ex Boiss. is a plant species reported from central Africa and the southern Arabian Peninsula, belonging to the family of Euphorbiaceae. The plant has ethnobotanical values and is well-known for its milky latex, which has been turned into medicine to treat various ailments. To the best of our knowledge, there have been no literature reports available on phytochemical constituents and antiproliferative mechanism of E. cactus. In the current study, the phytochemical investigation of E. cactus methanolic extract (ECME) resulted in the isolation and characterization of four secondary metabolites, which are reported for the first time from this plant species. In addition, the results of 1,1-diphenyl-2-picrylhydrazyl (DPPH•) and ferrous ion chelating (FIC) assays expressed maximum antioxidant activity by ECME and the isolated phytochemicals. Furthermore, ECME exerted a promising antiproliferative effect against different cancer cell lines, and the A549 lung cancer cells were the most sensitive with an IC50 value of 20 µg/mL. The antiproliferative action of ECME in A549 cells was associated with cell accumulation in the G2/M phase and an increase in early and late apoptosis. In addition, RT-PCR and western blot analysis revealed that ECME decreased the anti-apoptotic (Bcl-2) expression, while the expression of pro-apoptotic (Bax) and caspase-3 were increased. This study provides the first insight into the phytochemical constituents and the antiproliferative mechanism of ECME, implying that it could be exploited as a promising natural source for developing new cancer therapies. Further preclinical research is warranted to support the current results. [ABSTRACT FROM AUTHOR]

Date palm (Phoenix dactylifera L.) is the most important edible fruit crop in Saudi Arabia. Date palm cultivation and productivity are severely affected by various fungal diseases in date palm-producing countries. In recent years, black scorch disease has emerged as a devastating disease affecting date palm cultivation in the Arabian Peninsula. In the current survey, leaves and root samples were collected from deteriorated date palm trees showing variable symptoms of neck bending, leaf drying, tissue necrosis, wilting, and mortality of the entire tree in the Al-Ahsa region of Saudi Arabia. During microscopic examination, the fungus isolates growing on potato dextrose agar (PDA) media produced thick-walled chlamydospores and endoconidia. The morphological characterization confirmed the presence of Thielaviopsis punctulata in the date palm plant samples as the potential agent of black scorch disease. The results were further confirmed by polymerase chain reaction (PCR), sequencing, and phylogenetic dendrograms of partial regions of the ITS, TEF1-α, and β-tubulin genes. The nucleotide sequence comparison showed that the T. punctulata isolates were 99.9–100% identical to each other and to the T. punctulata isolate identified from Iraq-infecting date palm trees. The pathogenicity of the three selected T. punctulata isolates was also confirmed on date palm plants of Khalas cultivar. The morphological, molecular, and pathogenicity results confirmed that T. punctulata causes black scorch disease in symptomatic date palm plants in Saudi Arabia. Furthermore, seven commercially available fungicides were also tested for their potential efficacy to control black scorch disease. The in vitro application of the three fungicides Aliette, Score, and Tachigazole reduced the fungal growth zone by 86–100%, respectively, whereas the in vivo studies determined that the fungicides Aliette and Score significantly impeded the mycelial progression of T. punctulata with 40% and 73% efficiency, respectively. These fungicides can be used in integrated disease management (IDM) strategies to curb black scorch disease. [ABSTRACT FROM AUTHOR]

Considering the high risk of flooding during tropical cyclones (TCs), there is great practical significance in researching and predicting precipitation during TC landfalls. Using NECP FNL reanalysis data and GPM_MERGIR datasets, two TCs with similar trajectories, ARB 01 in 2002 and Luban in 2018, were analyzed. For ARB 01 and Luban, there are separate effects of wind shear at different heights on the development of vertical motion. Meridional wind shear affects the main deviation direction of vertical motion (downshear), while zonal wind shear mainly affects the deviation direction of vertical motion to the left or right of downshear. The divergent configuration of wind promotes the development of vertical motion. The influence of wind speed provided ideal conditions for ARB 01 to generate symmetric precipitation along its path when it made landfall. Additionally, more water vapor support was obtained from the southern Indian Ocean, which enabled ARB 01 to have a larger and broader average precipitation rate after landing. [ABSTRACT FROM AUTHOR]

Primary ciliary dyskinesia (PCD) is a poorly understood disorder. It is primarily autosomal recessive and is prevalent in tribal communities of the United Arab Emirates due to consanguineous marriages. This retrospective study aimed to assess the pathogenicity of the genetic variants of PCD in indigenous patients with significant clinical respiratory problems. Pathogenicity scores of variants obtained from the chart review were consolidated using the Ensembl Variant Effect Predictor. The multidimensional dataset of scores was clustered into three groups based on their pathogenicity. Sequence alignment and the Jensen–Shannon Divergence (JSD) were generated to evaluate the amino acid conservation at the site of the variation. One-hundred and twelve variants of 28 genes linked to PCD were identified in 66 patients. Twenty-two variants were double heterozygous, two triple heterozygous, and seven homozygous. Of the thirteen novel variants, two, c.11839 + 1G > A in dynein, axonemal, heavy chain 11 (DNAH11) and p.Lys92Trpfs in dynein, axonemal, intermediate chain 1 (DNAI1) were associated with dextrocardia with situs inversus, and one, p.Gly21Val in coiled-coil domain-containing protein 40 (CCDC40), with absent inner dynein arms. Homozygous C1orf127:p.Arg113Ter (rs558323413) was also associated with laterality defects in two related patients. The majority of variants were missense involving conserved residues with a median JSD score of 0.747. Homology models of two deleterious variants in the stalk of DNAH11, p.Gly3102Asp and p.Leu3127Arg, revealed structural importance of the conserved glycine and leucine. These results define potentially damaging PCD variants in the region. Future studies, however, are needed to fully comprehend the genetic underpinnings of PCD. [ABSTRACT FROM AUTHOR]

The Arabian Peninsula, located at the nexus of Africa, Europe, and Asia, was implicated in early human migration. The Arab population is characterized by consanguinity and endogamy leading to inbreeding. Global genome-wide association (GWA) studies on metabolic traits under-represent the Arab population. Replicability of GWA-identified association signals in the Arab population has not been satisfactorily explored. It is important to assess how well GWA-identified findings generalize if their clinical interpretations are to benefit the target population. Our recent study from Kuwait, which performed genome-wide imputation and meta-analysis, observed 304 (from 151 genes) of the 4746 GWA-identified metabolic risk variants replicable in the Arab population. A recent large GWA study from Qatar found replication of 30 GWA-identified lipid risk variants. These complementing studies from the Peninsula increase the confidence in generalizing metabolic risk loci to the Arab population. However, both the studies reported a low extent of transferability. In this review, we examine the observed low transferability in the context of differences in environment, genetic correlations (allele frequencies, linkage disequilibrium, effect sizes, and heritability), and phenotype variance. We emphasize the need for large-scale GWA studies on deeply phenotyped cohorts of at least 20,000 Arab individuals. The review further presents GWA-identified metabolic risk variants generalizable to the Arab population. [ABSTRACT FROM AUTHOR]

The Arabian Peninsula is a region characterized by diverse climatic conditions due to its location and geomorphological characteristics. Its precipitation patterns are characterized by very low annual amounts with great seasonal and spatial variability. Moreover, extreme events often lead to flooding and pose threat to human life and activities. Towards a better understanding of the spatiotemporal features of precipitation in the region, a thirty-year (1986-2015) climatic analysis has been prepared with the aid of the state-of-the-art numerical modeling system RAMS/ICLAMS. Its two-way interactive nesting capabilities, explicit cloud microphysical schemes with seven categories of hydrometeors and the ability to handle dust aerosols as predictive quantities are significant advantages over an area where dust is a dominant factor. An extended evaluation based on in situ measurements and satellite records revealed a good model behavior. The analysis was performed in three main components; the mean climatic characteristics, the rainfall trends and the extreme cases. The extremes are analyzed under the principles of the extreme value theory, focusing not only on the duration but also on the intensity of the events. The annual and monthly rainfall patterns are investigated and discussed. The spatial distribution of the precipitation trends revealed insignificant percentage differences in the examined period. Furthermore, it was demonstrated that the eastern part and the top half of the western Arabian Peninsula presented the lowest risk associated with extreme events. Apart from the pure scientific interest, the present study provides useful information for different sectors of society and economy, such as civil protection, constructions and reinsurance. [ABSTRACT FROM AUTHOR]

In hot and humid climatic conditions, cooling tends to dominate building thermal energy use. Cooling loads can be reduced through the adoption of efficient building envelope materials, such as Structural Insulated Panels (SIPs). This study quantifies the life cycle cost and operational energy of a representative case-study house in Bahrain using SIPs and hollow concrete blocks (HCBs) for the envelope over a period of 50 years. Operational energy is calculated using a dynamic energy simulation tool, operational costs are calculated based on the energy demand and local tariff rates, and construction costs are estimated using market prices and quotations. The life cycle cost is quantified using the Net Present Cost technique. Results show that SIPs yield a 20.6% reduction in cooling energy use compared to HCBs. For SIP costs of 12 and 17 USD/m2, the SIP house was cheaper throughout, or had a higher capital cost than the HCB house (breaking even in year 33), respectively. We propose policy recommendations with respect to material pricing, electricity tariffs, and energy efficiency, to improve the operational energy efficiency of houses in Bahrain and similar countries along the Arabian Peninsula. [ABSTRACT FROM AUTHOR]

During the past 100 years, Rift Valley fever virus (RVFV), a mosquito-borne virus, has caused potentially lethal disease in livestock, and has been associated with significant economic losses and trade bans. Spillover to humans occurs and can be fatal. Here, we combined data on RVF disease in humans (22 countries) and animals (37 countries) from 1931 to 2020 with seroprevalence studies from 1950 to 2020 (n = 228) from publicly available databases and publications to draw a more complete picture of the past and current RVFV epidemiology. RVFV has spread from its original locus in Kenya throughout Africa and into the Arabian Peninsula. Throughout the study period seroprevalence increased in both humans and animals, suggesting potentially increased RVFV exposure. In 24 countries, animals or humans tested positive for RVFV antibodies even though outbreaks had never been reported there, suggesting RVFV transmission may well go unnoticed. Among ruminants, sheep were the most likely to be exposed during RVF outbreaks, but not during periods of cryptic spread. We discuss critical data gaps and highlight the need for detailed study descriptions, and long-term studies using a one health approach to further convert the patchwork of data to the tale of RFV epidemiology. [ABSTRACT FROM AUTHOR]

Rift Valley fever phlebovirus (RVFV) infects humans and a wide range of ungulates and historically has caused devastating epidemics in Africa and the Arabian Peninsula. Lesions of naturally infected cases of Rift Valley fever (RVF) have only been described in detail in sheep with a few reports concerning cattle and humans. The most frequently observed lesion in both ruminants and humans is randomly distributed necrosis, particularly in the liver. Lesions supportive of vascular endothelial injury are also present and include mild hydropericardium, hydrothorax and ascites; marked pulmonary congestion and oedema; lymph node congestion and oedema; and haemorrhages in many tissues. Although a complete understanding of RVF pathogenesis is still lacking, antigen-presenting cells in the skin are likely the early targets of the virus. Following suppression of type I IFN production and necrosis of dermal cells, RVFV spreads systemically, resulting in infection and necrosis of other cells in a variety of organs. Failure of both the innate and adaptive immune responses to control infection is exacerbated by apoptosis of lymphocytes. An excessive pro-inflammatory cytokine and chemokine response leads to microcirculatory dysfunction. Additionally, impairment of the coagulation system results in widespread haemorrhages. Fatal outcomes result from multiorgan failure, oedema in many organs (including the lungs and brain), hypotension, and circulatory shock. Here, we summarize current understanding of RVF cellular tropism as informed by lesions caused by natural infections. We specifically examine how extant knowledge informs current understanding regarding pathogenesis of the haemorrhagic fever form of RVF, identifying opportunities for future research. [ABSTRACT FROM AUTHOR]

The comparison between crustal stress and surface strain azimuthal patterns has provided new insights into several complex tectonic settings worldwide. Here, we performed such a comparison for Egypt taking into account updated datasets of seismological and geodetic observations. In north-eastern Egypt, the stress field shows a fan-shaped azimuthal pattern with a WNW–ESE orientation on the Cairo region, which progressively rotated to NW–SE along the Gulf of Aqaba. The stress field shows a prevailing normal faulting regime, however, along the Sinai/Arabia plate boundary it coexists with a strike–slip faulting one (σ1 ≅ σ2 > σ3), while on the Gulf of Suez, it is characterized by crustal extension occurring on near-orthogonal directions (σ1 > σ2 ≅ σ3). On the Nile Delta, the maximum horizontal stress (SHmax) pattern shows scattered orientations, while on the Aswan region, it has a WNW–ESE strike with pure strike–slip features. The strain-rate field shows the largest values along the Red Sea and the Sinai/Arabia plate boundary. Crustal stretching (up to 40 nanostrain/yr) occurs on these areas with WSW–ENE and NE–SW orientations, while crustal contraction occurs on northern Nile Delta (10 nanostrain/yr) and offshore (~35 nanostrain/yr) with E–W and N–S orientations, respectively. The comparison between stress and strain orientations over the investigated area reveals that both patterns are near-parallel and driven by the same large-scale tectonic processes. [ABSTRACT FROM AUTHOR]

The genus Hydnora (Hydnoraceae) is one of the basal angiosperms in the order Piperales, found in the semi-arid regions of Africa, and the Southern Arabian Peninsula. Plants in this genus play essential roles in communities around the world as revealed by various studies. Currently, there are eight species of the genus Hydnora; seven in Africa and one in the Arabian Peninsula. Notably, Hydnora abyssinica A.Br. and Hydnora africana Thunb. are widely distributed compared to other species. They are widely used for their medicinal and nutritional values. The information on ethnobotany, chemistry, pharmacology, and distribution of genus Hydnora was gathered using phytochemical and ethnobotanical books, electronic sources, and published articles. Preliminary phytochemical screening shows that flavonoids, phenolics, proanthocyanidins, and tannins are the main compounds in H. abyssinica and H. africana. Furthermore, 11 compounds have been isolated from H. abyssinica. The biological activities of H. abyssinica and H. africana have been reported. They include antibacterial, antiproliferative, antioxidant, antidiarrhea, and antifungal potentials. Despite the Hydnora species being practiced in ancient folkloric medicine, their traditional uses and pharmacological value are poorly documented. Based on the available information on ethnobotany, phytochemistry, pharmacology, and distribution, we aim to provide research gaps and challenges for a better understanding of this genus. This may be resourceful in the development of effective phytomedicines, and aid in conservation. The available studies on this genus on some aspects such as phytochemistry, pharmacological activities, and distribution are under-reported hence the need for further research. [ABSTRACT FROM AUTHOR]