114 research outputs found

    Gravity theory in SAP-geometry

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    The aim of the present paper is to construct a field theory in the context of absolute parallelism (Teleparallel) geometry under the assumption that the canonical connection is semi-symmetric. The field equations are formulated using a suitable Lagrangian first proposed by Mikhail and Wanas. The mathematical and physical consequences arising from the obtained field equations are investigated.Comment: 14 pages, References added and a reference updated, minor correction

    LEADING CAUSES AND POSSIBLE ENVIRONMENTAL CONTRIBUTORS FOR END STAGE RENAL DISEASE IN ALMADINAH REGION IN SAUDI ARABIA

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    To find-out the leading causes and the possible environmental contributors for End Stage Renal Disease (ESRD) in Al-Madinah region, KSA.. 156 patients suffering from ESRD and 160 apparently healthy subjects of comparable age and sex were included. None of the participants was occupationally exposed to lead, cadmium and/or mercury. None affection of the control subjects with renal diseases was confirmed. Patients with undefined leading causes for ESRD (44) and an equal number of the control subjects were subjected to determine their blood levels of lead, cadmium and mercury. The study revealed that the main leading causes of ESRD in Al-Madinah region were hypertension, obstructive uropathy and diabetes mellitus. Environmental pollutants of lead (Pb) and cadmium (Cd) contributed to ESRD in Al-Madinah region particularly in urban areas. Mercury (Hg) was not a pollutant in Al-Madinah region. The study recommended early diagnosis and proper control of hypertension, obstructive uropathy and diabetes mellitus. It also recommended regular environmental monitoring for (Pb) and cadmium (Cd) levels and finds the sources of their elevations and efforts should be raised up to eliminate them

    Acute effects of cigarette smoking in habitual smokers, a focus on endothelial function

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    AbstractBackgroundThe chronic effect of cigarette (cig.) smoking is well established. The acute effect of smoking abolishes the concept, argued by heavy smokers, to decrease the number of smoked cigarettes instead of quitting.AimTo detect the acute effects of cigarette smoking and the duration of these effects.Patients and methodsThirty four smokers (age 21–35years) were studied at 3 occasions; 9h after the last cig. smoking, 5min after one cig. smoking and 30min after 3 cig. smoking within 30min. They were subjected to measurement of both ventricular functions using standard and tissue Doppler imaging (TDI), aortic distensibility, stiffness and endothelial function assessment by endothelium-dependent flow-mediated dilatation (FMD) and maximum vasodilatation.ResultsAfter one cigarette smoking, we found a statistically significant effect on blood pressure, Heart Rate, FMD percent, Dilation Ratio, aortic distensibility (P=0.007), and aortic stiffness index (ASI) (P=0.01). Furthermore the LV diastolic function was significantly impaired after smoking. Despite disappearance of acute effect of 3 cig. smoking within 30min on blood pressure, Heart Rate and aortic distensibility, a significant difference was still found as regards FMD percent and dilation ratio denoting the extension of the endothelial dysfunction for more than 30min after the last cigarette.ConclusionMany acute changes occur following one cigarette smoking even in habitual smokers. Persistence of endothelial dysfunction parameters after smoking indicates the failure of circulation adaptation in response to such offense that might contribute to the precipitation of acute events in vulnerable patients

    Student Partnership in E-learning: the Development of Online Resources for Students by Students in Dentistry

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    Dentistry is a dynamic and ever changing specialty that has been strongly influenced by developments in technology and therefore our teaching strategies must evolve to keep pace with these changes. E-learning has become an integral part of the dental curriculum, with a marked increase in use over recent years. However dental students have up until now been the recipients rather than active participants in the development of dental e-learning resources. Bovill et al (2011) conclude that it is incumbent upon us to reconsider students' roles in their education and reposition students to take a more active part - as co- creators of teaching approaches, course design and curricula. In this paper the presenters will outline the design and product of a self- selected study module (SSM) offered to year five dental students in e-learning. The SSM offers the opportunity for students to work as small teams with the school learning technologist and academic staff to identify, design, develop and evaluate quality-assured e-learning objects. Each group (n=2) with the guidance and quality assurance of academic staff will create a resource that can be integrated within the current University of Glasgow BDS curriculum for future years. It will become a useful revision resource that will supplement the learning and teaching received elsewhere within the course and will be accessible to all dental students in Scotland via the Scottish Dental Education Online (SDEO) programme. The SSM provides the opportunity of student participation in learning with technology and designing aspects of the curriculum, and aligns with the University's Learning and Teaching strategic objective of building staff-student partnerships to promote student engagement with learning

    The Use of Ceramic Waste Powder (CWP) in Making Eco-Friendly Concretes

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    The global production of ceramic waste powder (CWP), which is produced during the final polishing process of ceramic tiles, exceeds 22 billion tons. The disposal of CWP in landfills will cause significant environmental problems (i.e., soil, air, and groundwater pollution). CWP is characterized by its chemical composition that is mainly composed of silica (SiO2) and alumina (Al2O3). Both minerals represent more than 80% of the CWP composition. CWP has potentials to be used as an ingredient to partially or entirely replacing Portland cement to make eco-friendly concretes. This chapter summarizes the effect of using CWP in making eco-friendly concretes, with a particular focus on using CWP as a partial cement replacement in conventional-vibrated concrete (CVC) and self-compacting concrete (SCC), and the production of zero-cement alkali-activated concrete (AAC)

    Can a foreign body migrate against natural body barriers?

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    Pericardial foreign bodies (FBs) are a rare cause of chest pain in children. They can reach the pericardium through several routes including direct or iatrogenic implantation, transbronchial or transesophageal migration of inhaled or swallowed FBs. We reported a case of a 4-year-old girl presenting with persistent chest pain for 1 month. The child described the pain as ‘stitching’ in nature localized on the left side of the sternum. The child presented with increased pain intensity and a new onset of fever and cough. No history of chocking or swallowing of FB and no signs of trauma or child abuse were noted. Chest radiography revealed a needle in the left side of the chest. Computed tomography scan and echocardiography were used to precisely localize the needle and exclude intracardiac extension. ECG showed elevated ST segment and cardiac enzymes were normal. Removal of the needle was carried out surgically under fluoroscopic guidance. A small portion of the needle was found intrapericardially complicated by localized purulent pericarditis. The child had uneventful recovery and was discharged from the hospital on postoperative day 3.Keywords: foreign bodies, pain, pediatrics, pericardium, thoracic surger

    Do CRP levels predict severity in COVID-19 hospitalized Egyptian patients?

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    Background:  Coronavirus disease 2019 (COVID-19) is a rapidly spreading virus with a wide range of clinical manifestations. To manage treatment programs and promptly assess patient severity, prognostic factors must be identified early. Objectives: The purpose of this study was to investigate if there was a link between the severity of COVID-19 and the C-reactive protein (CRP) level on admission. Methods: On admission clinical and laboratory data from 323 patients with laboratory-confirmed COVID-19 were gathered from an Isolation Hospital records from April 10, 2020 to July 30, 2020. CRP was determined in all participants using an automated analyzer and a commercially available latex-enhanced immuno-turbidimetric assay. Results: The most prevalent presenting symptom was fever (39.3%), followed by cough (38.4%).  Coronavirus disease 2019 severity and ICU admission were both predicted by high CRP levels (p < /em><0.001).  C-reactive protein levels were also greater in those who had more chest discomfort, as indicated by CT chest abnormalities (p < /em><0.001). Conclusion: Serum CRP is a simple and effective prognosticator for early prediction of COVID-19 severity

    MicroRNA expression analysis in endometriotic serum treated mesenchymal stem cells

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    Endometriosis is defined by presence of endometrial-like-tissue outside the uterus. Recently, ectopic endometriotic lesions have been suggested to originate by abnormal differentiation of endometrial mesenchymal stem cells (eMSCs). MicroRNAs (miRNAs) play an important role in the pathophysiology of endometriosis. Through a PCR array approach, we aimed to assess the differential expression of microRNAs in human eMSC treated in culture with sera derived from women with severe endometriosis. Sera were collected from five patients with severe endometriosis and three control women and added individually in the culture medium to conduct experimental and control eMSC sets, respectively. Regular microscopic follow-up for cell morphology was performed. SYBR Green based real-time PCR array was used to assess the expression of 84 miRNAs. Bioinformatics analysis was done to predict the target genes of the significantly dysregulated miRNAs and their enriched biological processes and pathways. Thirty-two miRNAs were found significantly dysregulated in experimental cultures. Functional enrichment analysis revealed several endometriosis associated biological processes and pathways were enriched by target genes of these miRNAs. In conclusion, treatment of human eMSCs with sera of severe endometriosis cases affects the expression of certain miRNAs and their target genes. This may result in altering cell functions and consequently, endometriosis development

    Crack sliding model for non-shear FRP-reinforced slender concrete elements under shear

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    Fiber-reinforced polymer (FRP)-reinforced concrete (RC) elements fail under one-way shear in a devastating and complicated manner with no adequate warning. In recent decades, there has been pioneering research in this area; however, there is no agreement among researchers regarding mechanically-based models. Thus, in this current study, a plasticity-based model is developed for FRP-RC elements under shear. A selected model was firstly assessed for its accuracy, consistency, and safety against an extensive experimental database. Secondly, a plasticity-based model (i.e., crack shear sliding model) was adapted, refined, and proposed for FRP-RC elements under one-way shear. The two proposed models were found to be reliable and more accurate with respect to selected existing methods. Modeling of FRP’s axial rigidity is more consistent only under Young’s modulus with respect to the experimental database. Several concluding remarks on the selected existing models are outlined and discussed to assist the future development of these models and design codes
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