224 research outputs found

    Evolution of a late triassic fluvial system, NW Libya

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    Fluvial systems, channel sandbodies and valley fills have been widely studied and documented in the literature, with particular attention paid to their internal structures. Although fluvial architecture and channel body geometry have been widely linked to baselevel change, tectonics and accommodation space, few studies have taken a holistic approach of additionally incorporating climatic signatures, diagenesis and width/thickness (W/T) of low net to gross fluvial systems. To remedy this situation, one of the first studies of a series of excellent fluvial exposures of the Late Triassic Abu Shaybah Formation (216.5 -199.6 Ma; c.15.9 Myrs), located along the Jabal Nafusah of northern Libya have been examined. The fluvial deposits of the Abu Shaybah Formation have been recognized to be part of an incised valley fill situated along a major strike slip fault zone, now demarked by the Jabal Nafusah escarpment. The associated architecture of the fluvial systems are identified by channel sand bodies with low W/T 10-15. The architecture of the Abu Shaybah Formation changes up section as it becomes less influenced by tectonic activity, while climatic signatures become more marked by variables in stream discharges and sediment flux, recognized by channel aggradation and degradation of the fluvial systems. Such an occurrence has been used to help correlate the fluvial succession laterally and recognise how tectonism provides the space for and distribution of rivers while climate controls the sediment supply and facies evolution. Detailed petrographie analysis of the Abu Shaybah Formation has revealed the importance of new clay mineral growths for the identification of sequence boundaries. This research demonstrates the importance of taking a holistic approach when studying fluvial successions and has important implications for low net to gross fluvial reservoirs as a potential exploration target in the Al Kufrah and Sirte Basins

    Synthesis and Characterizations of Titanium Tungstosilicate and Tungstophosphate Mesoporous Materials

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    The work reports a development approach for the synthesis of novel multi-components mesoporous materials of titanium tungstate (meso-TiW) titanium tungstosilicate (meso-TiWSi) and tungstophosphate (meso-TiWP) mixed oxides that have high surface area and ordered mesoporous structures at nanometer length scale. Using the solvent evaporation-induced self-assembly (EISA) new oxides of bi- and tri-component of meso-TiW, meso-TiWSi and meso-TiWP oxides with different compositions and porosity were achieved. The physicochemical properties of the mesoporous oxides were characterized by X-ray diffraction, BET surface area analyzer, scanning, and transmission electron microscopes. Subject to the oxide composition, the obtained meso-TiW, meso-TiWSi and meso-TiWP exhibits high surface area, ordered 2D hexagonal mesostructured with order channels extended over a large area. The produced meso-TiW, meso-TiWSi, and meso-TiWP adsorbents exhibit good adsorption efficiency for the removal of Pb(II), Cd(II) and Hg(II) ions from water solution due to the presence of high surface area and accessibility of surface active sites. The adsorption efficiency of these mesoporous oxide reaches up to 95% and is found to be dependent contact time and adsorbents dose. The synthesis strategy is particularly advantageous for the production of new complex (multi-component) inorganic mesoporous materials that might have an application in the field of environmental, catalysis or energy storage and production

    An investigation into the implementation of Building Information Modeling in the Middle East

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    Architectural, Engineering and Construction (AEC) industry. There have been many changes in the past few years in the use of BIM and how to implement BIM in the AEC Industry. The purpose of this research is to examine the current status of BIM in the Middle East by exploring the extent of adoption of BIM among stakeholders in the AEC industry in this region. To this end surveys were sent out to 297 and empirical statistics have been applied. The respondents acknowledged they were aware of the benefits of BIM in terms of it being a more effective method for designing and managing construction projects by supporting collaboration, improving the quality of the design by providing the ability to closely visualize designs in 3D and rendered forms and providing a platform which would facilitate the sharing of information relevant for design, construction and maintenance of buildings over their entire lifecycle. However, only 20% of AEC organizations in the Middle East are using BIM or are in the process of adopting BIM, with more professionals beginning to adopt BIM although most professionals within this region still look at BIM just as an advanced AutoCAD tool. Raising awareness related to the benefits of BIM and increasing training opportunities in the Middle East are necessary in order to allow all stakeholders to benefit substantially from BIM

    The Arabic version of the Juvenile Arthritis Multidimensional Assessment Report (JAMAR)

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    The Juvenile Arthritis Multidimensional Assessment Report (JAMAR) is a new parent/patient reported outcome measure that enables a thorough assessment of the disease status in children with juvenile idiopathic arthritis (JIA). We report the results of the cross-cultural adaptation and validation of the parent and patient versions of the JAMAR in the Arabic language. The reading comprehension of the questionnaire was tested in 10 JIA parents and patients. Each participating centre was asked to collect demographic and clinical data and the JAMAR in 100 consecutive JIA patients or all consecutive patients seen in a 6-month period and to administer the JAMAR to 100 healthy children and their parents. The statistical validation phase explored descriptive statistics and the psychometric issues of the JAMAR: the 3 Likert assumptions, floor/ceiling effects, internal consistency, Cronbach\u2019s alpha, interscale correlations, test\u2013retest reliability, and construct validity (convergent and discriminant validity). A total of 100 JIA patients (27.0% systemic JIA, 23.0% oligoarticular, 25.0% RF negative polyarthritis, and 25.0% other categories) and 100 healthy children, were enrolled in one paediatric rheumatology centre. The JAMAR components discriminated well healthy subjects from JIA patients. All JAMAR components revealed satisfactory psychometric performances. In conclusion, the Arabic version of the JAMAR is a valid tool for the assessment of children with JIA and is suitable for use both in routine clinical practice and in clinical research

    Evaluation of efficient vehicular ad hoc networks based on a maximum distance routing algorithm

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    Traffic management at road intersections is a complex requirement that has been an important topic of research and discussion. Solutions have been primarily focused on using vehicular ad hoc networks (VANETs). Key issues in VANETs are high mobility, restriction of road setup, frequent topology variations, failed network links, and timely communication of data, which make the routing of packets to a particular destination problematic. To address these issues, a new dependable routing algorithm is proposed, which utilizes a wireless communication system between vehicles in urban vehicular networks. This routing is position-based, known as the maximum distance on-demand routing algorithm (MDORA). It aims to find an optimal route on a hop-by-hop basis based on the maximum distance toward the destination from the sender and sufficient communication lifetime, which guarantee the completion of the data transmission process. Moreover, communication overhead is minimized by finding the next hop and forwarding the packet directly to it without the need to discover the whole route first. A comparison is performed between MDORA and ad hoc on-demand distance vector (AODV) protocol in terms of throughput, packet delivery ratio, delay, and communication overhead. The outcome of the proposed algorithm is better than that of AODV

    Revamping established project procurement approaches to support BIM implementation

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    Purpose Previous studies have established to a great extent that regulatory frameworks and, in particular, procurement approaches – that are common in a particular context – have a major impact on the success of building information modelling (BIM) implementation in construction projects. Despite the close links between these two concepts, research on the effect of procurement approaches on BIM implementation is scarce. To address this gap, this paper aims to investigate the barriers that affect BIM implementation through the lens of procurement approaches. Design/methodology/approach A mixed-method approach was adopted using a questionnaire survey (n = 116) and interviews with key stakeholders (n = 12) in Jordan. The outcomes of the quantitative parts were augmented with findings from interviews. Findings It was revealed that the deployment of unfavourable construction procurement approaches represents a major hurdle towards BIM implementation. Though essential for enhancing BIM implementation, it is revealed that a fundamental change from the common design-bid-build (DBB) to more collaborative procurement approaches remains infeasible in view of the realities that govern the construction industry. Research limitations/implications It was revealed the deployment of unfavourable construction procurement approaches represents a major hurdle towards BIM implementation. Though essential for enhancing BIM implementation, it is revealed that a fundamental change from the common DBB to more collaborative procurement approaches remains infeasible given the realities that govern the construction industry. Originality/value As the first of its kind, a set of recommendations for establishing supportive, workable procurement that does not deviate significantly from common procedures and practices is presented. Rather than advocating a shift to procurement approaches that are aligned with BIM, the findings offer novel insight into the necessity of developing a framework within the boundaries of the current and widely adopted procurement approaches to address the identified construction procurement issues and facilitate BIM implementation

    The Omani Arabic version of the Juvenile Arthritis Multidimensional Assessment Report (JAMAR)

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    The Juvenile Arthritis Multidimensional Assessment Report (JAMAR) is a new parent/patient reported outcome measure that enables a thorough assessment of the disease status in children with juvenile idiopathic arthritis (JIA). We report the results of the cross-cultural adaptation and validation of the parent and patient versions of the JAMAR in the Omani Arabic language. The reading comprehension of the questionnaire was tested in 10 JIA parents and patients. Each participating centre was asked to collect demographic, clinical data and the JAMAR in 100 consecutive JIA patients or all consecutive patients seen in a 6-month period and to administer the JAMAR to 100 healthy children and their parents. The statistical validation phase explored descriptive statistics and the psychometric issues of the JAMAR: the 3 Likert assumptions, floor/ceiling effects, internal consistency, Cronbach\u2019s alpha, interscale correlations, test\u2013retest reliability, and construct validity (convergent and discriminant validity). A total of 57 JIA patients (22.8% systemic, 28.1% oligoarticular, 35.1% RF negative polyarthritis, 14.0% other categories) and 85 healthy children, were enrolled in two centres. Notably, none of the enrolled JIA patients is affected with enthesitis-related arthritis or undifferentiated arthritis. The JAMAR components discriminated well healthy subjects from JIA patients. All JAMAR components revealed satisfactory psychometric performances. In conclusion, the Omani Arabic version of the JAMAR is a valid tool for the assessment of children with JIA and is suitable for use both in routine clinical practice and clinical research

    The Libyan Arabic version of the Juvenile Arthritis Multidimensional Assessment Report (JAMAR)

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    The Juvenile Arthritis Multidimensional Assessment Report (JAMAR) is a new parent/patient reported outcome measure that enables a thorough assessment of the disease status in children with juvenile idiopathic arthritis (JIA). We report the results of the cross-cultural adaptation and validation of the parent and patient versions of the JAMAR in the Libyan Arabic language. The reading comprehension of the questionnaire was tested in 10 JIA parents and patients. Each participating centre was asked to collect demographic, clinical data, and the JAMAR in 100 consecutive JIA patients or all consecutive patients seen in a 6-month period and to administer the JAMAR to 100 healthy children and their parents. The statistical validation phase explored descriptive statistics and the psychometric issues of the JAMAR: the 3 Likert assumptions, floor/ceiling effects, internal consistency, Cronbach\u2019s alpha, interscale correlations, test\u2013retest reliability, and construct validity (convergent and discriminant validity). A total of 100 JIA patients (22.0% systemic, 26.0% oligoarticular, 25.0% RF negative polyarthritis, and 27.0% other categories) and 100 healthy children, were enrolled in a paediatric rheumatology centre. The JAMAR components discriminated well healthy subjects from JIA patients. Notably, there is no significant difference between the healthy subjects and their affected peers in the school-related problems variable. All JAMAR components revealed satisfactory psychometric performances. In conclusion, the Libyan Arabic version of the JAMAR is a valid tool for the assessment of children with JIA and is suitable for use both in routine clinical practice and clinical research

    Management of Mucopolysaccharidosis Type I in Saudi Arabia: Insights from Saudi Arabia

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    Mucopolysaccharidosis (MPS) is a group of rare disorders that are characterized by intracellular accumulation of glycosaminoglycans with subsequent cellular and organ dysfunction. In the Middle East, especially Saudi Arabia, higher prevalence of MPS type I was observed compared to reported rates from European countries and the United States (U.S). The present work was developed as a part of the Saudi MPS Group’s efforts to address the current situation of MPS type I in Saudi Arabia and to reach a national consensus in the management of MPS type I. The first “Management of MPS Type I Advisory Board” meeting was held in Riyadh on May 2, 2019, to reflect the expert opinions regarding different aspects of MPS type I and develop this manuscript; eight consultants from different specialties (medical genetics, pediatric rheumatology, and pediatric endocrinology), representing six Saudi institutions, in addition to a global expert in genetics participated in the meeting
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