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Facies development and sedimentology of the Middle Miocene carbonates of the Raghama Formation, northeastern Saudi Arabia

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Acta Geochimica 2024年第1期43卷 87-96页

作者： mansour h.al-hashim Abdelbaset S.El-Sorogy Meshal Wadani Department of Geology and Geophysics College of ScienceKing Saud University2455Riyadh 11451Saudi Arabia

Ragahama Formation comprises a siliciclastic continental deposits followed by marine carbonates, representing prograding alluvial fans from adjacent high hinterlands seaward into lagoons and fringing reef environments. The present work aimed to document the facies development and sedimentology of the Raghama carbonates exposed along the eastern coastal plain of the Red Sea, northwestern Saudi Arabia. Four stratigraphic sections were measured and sampled(D1–D4) and thin sections and major and trace element analyses were prepared and applied for petrographic and geochemical approaches. The carbonates were subdivided into three successive fore-reef, reef-core, and back-reef depositional facies. Sandy stromatolitic boundstone, microbial laminites, dolomitic ooidal grainstone, bioclastic coralline algal wackestone, sandy bioclastic wackestone, and coral boundstones were the reported microfacies types. Petrographic analysis reveals that the studied carbonates were affected by dissolution, dolomitization, and aggrading recrystallization, which affects both the original micrite matrix and grains or acts as fracture and veinlet filling leading to widespread vuggy and moldic porosity. No evidence of physical compaction, suggesting rapid lithification and recrystallization during early diagenesis and prior to substantial burial and intensive flushing by meteoric waters. Most of the original microstructure of corals were leached and destructed. This is indicated by the higher depletion in Sr and Ca levels and increase in Mg,Na, Fe, and Mn levels, especially in section D1, in comparison with the worldwide carbonates.

关键词： Raghama Formation Miocene Diagenesis Geochemistry Saudi Arabia

Geochemistry,Petrogenesis and alteration of Rare-Metal-Bearing Granitoids and Mineralized Silexite of the al-Ghurayyah Stock,Arabian Shield,Saudi Arabia

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Journal of Earth Science 2023年第5期34卷 1488-1510页

作者： hisham A.Gahlan Mokhles K.Azer Paul D.Asimow mansour h.al-hashim Department of Geology and Geophysics College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia Geological Sciences Department National Research CentreCairoEgypt Division of Geological&Planetary Sciences California Institute of TechnologyPasadena CA 91125USA

New data are presented for the rare-metal bearing A-type granitoids of the alGhurayyah stock in the northwestern segment of the Arabian Shield, a composite pluton intruding metamorphosed volcano-sedimentary successions of the Silasia Formation. Metals in the granitoids are variably enriched, with up to 1 990 μg/g Zn, 7 680 μg/g Zr, 2 316 μg/g Nb, 232 μg/g Ta, 485 μg/g hf, 670 μg/g Th, 137 μg/g U and 1 647 μg/g total rare earth elements(REE). The silexite is highly mineralized and yields higher maximum concentrations of several metals than the granitoids, including up to 1 860 μg/g Y, 9 400 μg/g Zr, 878 μg/g hf, 1 000 μg/g Th, and 2 029 μg/g total REE. The al-Ghurayyah stock has been assigned to an intraplate setting. Lithospheric delamination led to generation of mantle melts that supplied heat to melt the juvenile crust of the ANS. The fluorine and rare-metal enriched parental magma evolved by fractional crystallization. The quartz-rich silexite, distinct in character from ordinary hydrothermal vein quartz, is inferred to be co-genetic with the granitoids on the basis of their similar REE patterns;it is interpreted as a small volume of residual magma enriched in SiO2, volatiles, and trace metals. Mineralization took place both at the magmatic stage and later during a hydrothermal stage that concentrated these elements to economic grades.

关键词： Arabian Shield al-Ghurayyah rare metals silexite peralkaline granite hydrothermal metasomatism

Structural Setting and Kinematic Analysis of the halaban Region,Eastern Arabian Shield,Saudi Arabia

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Acta Geologica Sinica(English Edition) 2021年第3期95卷 750-760页

作者： Osama M.KASSEM Yousef A.alAMRI Faisal K.ZAIDI Abdel Aziz M.al BASSAM mansour h.al-hashim Department of Geology and Geophysics Faculty of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Kingdom of Saudi Arabia Department of Geology National Research CenterAl-Behoos str.12622 DokkiCairoEgypt

The vorticity analysis technique was applied to measure the different lithological units,such as schist,metagranite and metavolcano-sedimentary rocks,which are present in the halaban *** work aims to interpret the relationship between the different lithologies and the tectonic setting,in order to elucidate the nature of kinematic analysis in the halaban *** kinematic analyses were applied to feldspar porphyroclasts,quartz and hornblende for twenty-six *** kinematic vorticity number(Wm)for deformed rocks in the study area ranged from~0.6 to *** direction of the long axes for finite strain data(X axes)revealed a WNW trend with shallow *** direction of the short axes for finite strain data(Z axes)were represented by vertical with associated horizontal *** results of the kinematic vorticity and strain analyses are characterized by simple shear with different degrees of deformation in the halaban ***,our finite strain data shows no significant volume change during *** subhorizontal foliation was synchronized with thrusting and ***,throughout the overlying nappes,the same attitudes of tectonic contacts are observable,the nappes in the orogens being formed from simple shear deformation.

关键词： vorticity analysis strain analysis deformation halaban area Eastern Arabian Shield

MARIE:One-Stage Object Detection Mechanism for Real-Time Identifying of Firearms

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 279-298页

作者： Diana Abi-Nader hassan harb ali Jaber ali mansour Christophe Osswald Nour Mostafa Chamseddine Zaki Computer Science Department Faculty of SciencesLebanese UniversityBeirut146404Lebanon College of Engineering and Technology American University of the Middle EastEgaila54200Kuwait Lab-STICC CNRS UMR 6285ENSTA-BretagneBrest29200France

Security and safety remain paramount concerns for both governments and individuals *** today’s context,the frequency of crimes and terrorist attacks is alarmingly increasing,becoming increasingly intolerable to ***,there is a pressing need for swift identification of potential threats to preemptively alert law enforcement and security forces,thereby preventing potential attacks or violent *** advancements in big data analytics and deep learning have significantly enhanced the capabilities of computer vision in object detection,particularly in identifying *** paper introduces a novel automatic firearm detection surveillance system,utilizing a one-stage detection approach named MARIE(Mechanism for Realtime Identification of Firearms).MARIE incorporates the Single Shot Multibox Detector(SSD)model,which has been specifically optimized to balance the speed-accuracy trade-off critical in firearm detection *** SSD model was further refined by integrating MobileNetV2 and InceptionV2 architectures for superior feature extraction *** experimental results demonstrate that this modified SSD configuration provides highly satisfactory performance,surpassing existing methods trained on the same dataset in terms of the critical speedaccuracy *** these innovations,MARIE sets a new standard in surveillance technology,offering a robust solution to enhance public safety effectively.

关键词： Firearm and gun detection single shot multi-box detector deep learning one-stage detector MobileNet inception convolutional neural network

Characteristics of newly-formed cementum following emdogain application

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International Journal of Oral Science 2011年第1期3卷 21-26页

作者： Khalid al-hezaimi mansour al-Askar Abdulaziz al-Rasheed Eng.A.B.Bagshan Growth Factors and Bone Regeneration Research Chair King Saud UniversityRiyadhSaudi Arabia Department of Periodontology School of Dentistry King Saud UniversityRiyadh Saudi Arabia Eng.A.B.Bagshan Growth Factors and Bone Regeneration Research Chair King Saud UniversityRiyadh Saudi Arabia Department of Periodontology School of Dentistry King Saud UniversityRiyadhSaudi Arabia

Periodontal regenerative techniques have been proposed; however, the outcomes remain debatable. The present investigation assessed the regenerated cementum following enamel matrix derivative application in dehiscence-type defects. Buccal osseous dehiscences were surgically created on the maxillary cuspid, and the second and fourth premolars in five female beagle dogs. The treatment group （n=15 sites） received the enamel matrix derived application, whereas the control groups （n=15） did not. The dogs were sacrificed 4 months following treatment and the specimens were histologically and histometrically examined. The newly formed cementum was uneven in thickness and mineralization, overlapped the old cementum and exhibited functional orientation, cementocyte lacunae and collagen fibril bundles. Most of the histological specimens showed the presence of a gap between the newly formed cementum and the underlying dentin. Control sites did not exhibit any cementum formation. The present study concluded that newly formed cementum is of cellular type and exhibits multiple characteristics.

关键词： regeneration cementum enamel matrix protein

Diagnostic value of18F-FDG PET in the assessment of myocardial viability in coronary artery disease：A comparative study with99mTc SPECT and echocar-diography

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Journal of Geriatric Cardiology 2014年第3期11卷 229-236页

作者： mansour al Moudi Zhong-hua Sun Department of Medical Imaging and Nuclear Medicine King Saud Medical City Riyadh Saudi Arabia Discipline of Medical Imaging Department of Imaging and Applied Physics Curtin University GP0 Box U1987 Perth Western Australia 6845 Australia

ObjectiveTo investigate the diagnostic value of 18F-fluorodeoxyglucose positron emission tomography （18F-FDG PET） in the as-sessment of myocardial viability in patients with known coronary artery disease （CAD） when compared to99mTc single photon emission computed tomography （SPECT） and echocardiography, with invasive coronary angiography as the gold *** patients with diagnosed CAD met the selection criteria, with 10 of them （9 men, mean age 59.5 ± 10.5 years） undergoing all of these imaging proce-dures consisting of SPECT and PET, echocardiography and invasive angiography. Diagnostic sensitivity of these less invasive modalities for detection of myocardial viability was compared to invasive coronary angiography. Inter- and intra-observer agreement was assessed for di-agnostic performance of SPECT and *** all patients with proven CAD, 50% had triple vessel disease. Diagnostic sensitivity of SPECT, PET and echocardiography was 90%, 100% and 80% at patient-based assessment, respectively. Excellent agreement was achieved between inter-observer and intra-observer agreement of the diagnostic value of SPECT and PET in myocardial viability （k= 0.9）. Conclusion18F-FDG PET has high diagnostic value in the assessment of myocardial viability in patients with known CAD when com-pared to SPECT and echocardiography. Further studies based on a large cohort with incorporation of18F-FDG PET into patient management are warranted.

关键词： Coronary artery disease Diagnostic value Positron emission tomography Single photon emission computed tomography Vi-ability

Combined corneal CXL and photorefractive keratectomy for treatment of keratoconus: a review

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International Journal of Ophthalmology(English edition) 2019年第12期12卷 1929-1938页

作者： mansour M.al-Mohaimeed Department of Ophthalmology College of Medicine Qassim University

Keratoconus and iatrogenic keratectasia are the corneal ectatic disorders occurring due to biomechanical weakening of the cornea resulting in distorted images,myopia, and irregular astigmatism. Corneal collagen cross-linking(CXL) is performed to arrest keratoconus successfully. The main aim of this review is to discuss the safety and efficacy of the adjuvant therapies, such as the combination of CXL and photorefractive keratectomy(PRK) for the treatment of corneal ectatic disorders. A comprehensive literature search was performed using PubM ed, MEDLINE, and Scopus using keywords ‘collagen’‘keratoconus’,‘keratectasia’,‘collagen cross-linking’,and ‘photorefractive keratectomy’. Search results were restricted to clinical studies published in English. Corneal CXL effectively arrests the progression of keratoconus by enhancing corneal rigidity. however, functional vision is not improved by cross-linking. Combining CXL to refractive surgeries such as topography-guided PRK or transepithelial PRK is found to be a safe and effective method in providing corneal stability as well as significantly improving functional visual acuity with few minor complications. This combined technique also prevents regression of keratoconus and reduce the risk of keratectasia. CXL combined with PRK is a promising therapeutic approach in ophthalmology that can be successfully used to treat progressive keratoconus and other corneal ectatic disorders and to enhance visual acuity.

关键词： corneal collagen cross-linking photorefractive keratectomy keratoconus

Factors affecting single-step transepithelial photorefractive keratectomy outcome in the treatment of mild,moderate,and high myopia:a cohort study

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International Journal of Ophthalmology(English edition) 2022年第5期15卷 786-792页

作者： mansour M.al-Mohaimeed Department of Ophthalmology College of MedicineQassim UniversityQassimBuraidah 51452Saudi Arabia

AIM:To investigate the effect of preoperative factors on visual acuity,higher-order aberrations(hOAs),and index of success for spherical change(***)after transepithelial photorefractive keratectomy(t-PRK)for treating different grades of ***:This was a retrospective one-armed cohort study where patients with high,moderate,or mild myopia treated with single-step t-PRK using Amaris 500 hz excimer laser were evaluated for visual acuity,refractive status,corneal topography,hOAs,***,and mean efficiency and safety index before and 6 mo after ***:A total of 154 eyes of 77 patients with mild(n=59),moderate(n=83),and high(n=12)myopia were *** efficiency and safety indices for vision recovery by single-step t-PRK were 98%and 100%,*** achieved spherical equivalent(SE)was within 1 diopter(D)in 151(98%)*** median of the *** was 1.18[interquartile range(IQR)1.0,1.4].The change in *** was significantly correlated with age(P=0.007),6.5 mm ablation zone(Mann-Whitney U test,Pal–Wallis test,Pherical aberration,and aberration coefficient types of hOA increased significantly(Wilcoxon test,Pherical aberration and aberration coefficient hOAs by myopia grades(Phas promising short-term outcomes for refractive corrections and vision improvement to treat all three grades of myopia.

关键词： myopia refractive surgery trans-epithelial photorefractive keratectomy higher-order aberrations

An Efficient Path Planning Strategy in Mobile Sink Wireless Sensor Networks

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Computers, Materials & Continua 2022年第10期73卷 1237-1267页

作者： Najla Bagais Etimad Fadel Amal al-mansour Department of Computer Science Faculty of Computing and Information TechnologyKing Abdul-Aziz UniversityJeddah21589Saudi Arabia

Wireless sensor networks (WSNs) are considered the backbone ofthe Internet of Things (IoT), which enables sensor nodes (SNs) to achieveapplications similarly to human intelligence. however, integrating a WSNwith the IoT is challenging and causes issues that require careful *** the lifetime of a network through appropriately utilising energyconsumption is among the essential challenges due to the limited resourcesof SNs. Thus, recent research has examined mobile sinks (MSs), which havebeen introduced to improve the overall efficiency of WSNs. MSs bear theburden of data collection instead of consuming energy at the routeing bySNs. In a network, some areas generate more data through SNs that containfrequent, urgent messages. These messages carry sensitive data that must bedelivered immediately to user applications. Collecting such messages via MSs,especially on a large scale, increases delays, which are not tolerable in some realapplications. This issue has not been studied much. Thus, the present studyutilises the advantages of the priority parameter to concentrate on these areasand proposes a new model named ‘energy efficient path planning of MS-basedarea priority’ (EEPP-BAP). This method involves non-urgent and urgentmessages. It is comprised of four procedures. Initially, after SNs are distributedrandomly in a wide monitoring field, the monitoring field is partitionedinto equal zones according to priority, either differently or equally. Next isclustering based on the cluster head (Ch) selected to perform the particleswarm optimisation algorithm (PSO). Then, the MS moves first to the zoneswith higher priority and less distance to perform the brain storm optimisationalgorithm. Finally, for urgent messages from the other zones at which theMS continues, the proposed approach establishes a routeing technique usingmulti-hop communication based on the MS position and using PSO. The proposed solution is aimed at delivering urgent messages to MSs free of

关键词： Wireless sensor network priority urgent message swarm intelligence optimisation mobile sink clustering energy efficiency