118 research outputs found

    Structural Efficiency of Steel Stiffening Deck Systems in Suspension Bridges Due to Gravity Loads

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    In this paper, suspended stiffened decks in suspension bridges are considered. Three steel deck-stiffening systems are compared structurally; the plate girder, the box girder and the stiffening truss. A three-span continuous suspension bridge model is considered. Analysis is made by the second order non-linear deflection theory in its linearized form. Developed software is used for the analysis to determine the induced tension in the cable, moments, shears and deflections of the girders for any general live load case. AASHTO criteria for steel girders are adopted. AASHTO highway live loads -HL 93- are applied to Khartoum-Tuti Suspension Bridge in Khartoum, Sudan for each type of the stiffening systems. Ten load cases are considered and discussed. Results have shown that the most efficient type to resist gravity loads is the stiffening truss, followed by the box girder and last is the plate girde

    Support Vector Regression Based S-transform for Prediction of Single and Multiple Power Quality Disturbances

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    This paper presents a novel approach using Support Vector Regression (SVR) based S-transform to predict the classes of single and multiple power quality disturbances in a three-phase industrial power system. Most of the power quality disturbances recorded in an industrial power system are non-stationary and comprise of multiple power quality disturbances that coexist together for only a short duration in time due to the contribution of the network impedances and types of customers’ connected loads. The ability to detect and predict all the types of power quality disturbances encrypted in a voltage signal is vital in the analyses on the causes of the power quality disturbances and in the identification of incipient fault in the networks. In this paper, the performances of two types of SVR based S-transform, the non-linear radial basis function (RBF) SVR based S-transform and the multilayer perceptron (MLP) SVR based S-transform, were compared for their abilities in making prediction for the classes of single and multiple power quality disturbances. The results for the analyses of 651 numbers of single and multiple voltage disturbances gave prediction accuracies of 86.1% (MLP SVR) and 93.9% (RBF SVR) respectively. Keywords: Power Quality, Power Quality Prediction, S-transform, SVM, SV

    The Legal Aspects and the Enhanced Role of Cybersecurity in Protecting the Electronic Voting Process in the Context of Jordan Parliament Election Law No. (4) of 2022

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    This study, entitled: The legal aspects and the enhanced role of cybersecurity in protecting the electronic voting process , dealt with the concept of the electronic voting process, in addition to the most important characteristics of that process, as well as highlighting the pros and cons related to the electronic voting system. Then, the researchers singled out a proposed approach for the electronic voting process in terms of the adopted mechanism and cyber protection in accordance with the provisions of the Jordanian Election Law No. (4) of 2022. At the end of the research, the researchers recommended activating the text of Article 40 of the electoral law by issuing legislation that regulates the electronic voting process and enhances the protection of cyber security, and then updating the technical and legislative system of the Independent Election Commission and the Ministry of Political Development

    Rapid thermal annealing: An efficient method to improve the electrical properties of tellurium compensated Interfacial Misfit GaSb/GaAs heterostructures

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    The effect of thermal annealing on Te compensated Interfacial Misfit GaSb/GaAs heterostructures is investigated by using two different thermal annealing procedures, namely rapid thermal annealing and furnace annealing. The electrical properties of the devices are studied by using Current–Voltage, Capacitance–Voltage and Deep Level Transient Spectroscopy techniques. It is observed that rapid thermal annealing treatment is superior in terms of improvement of the electrical characteristics compared to furnace annealing treatment. The lowest leakage current and defect concentration are obtained when rapid thermal annealing is employed

    Primary healthcare policy implementation in the Eastern Mediterranean region: Experiences of six countries

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    Background: Primary healthcare (PHC) is essential for equitable access and cost-effective healthcare. This makes PHC a key factor in the global strategy for universal health coverage (UHC). Implementing PHC requires an understanding of the health system under prevailing circumstances, but for most countries, no data are available. Objectives: This paper describes and analyses the health systems of Bahrain, Egypt, Lebanon, Qatar, Sudan and the United Arab Emirates, in relation to PHC. Methods: Data were collected during a workshop at the WONCA East Mediterranean Regional Conference in 2017. Academic family physicians (FP) presented their country, using the WONCA framework of 11 PowerPoint slides with queries of the country demographics, main health challenges, and the position of PHC in the health system. Results: All six countries have improved the health of their populations, but currently face challenges of non-communicable diseases, aging populations and increasing costs. Main concerns were a lack of trained FPs in community settings, underuse of prevention and of equitable access to care. Countries differed in the extent to which this had resulted in coherent policy. Conclusion: Priorities were (i) advocacy for community-based PHC to policymakers, including the importance of coordination of healthcare at the community level, and UHC to respond to the needs of populations; (ii) collaboration with universities to include PHC as a core component of every medical curriculum; (iii) collaboration with communities to improve public understanding of PHC; (iv) engagement with the private sector to focus on PHC and UHC

    Investigation of the structural, optical and electrical properties of indium-doped TiO2 thin films grown by Pulsed Laser Deposition technique on low and high index GaAs planes

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    © 2020 Elsevier B.V. The properties of In-doped TiO2 grown by Pulsed Laser Deposition on (1 0 0) and (3 1 1)B GaAs substrates have been investigated. X-ray diffraction and photoluminescence results have shown that samples grown on (3 1 1)B GaAs planes have better crystallographic properties than those grown on (1 0 0). Both anatase and rutile phases were detected in samples with lower In-doping (In = 5 nm) while only rutile phase was observed for higher In-doped samples (In = 15 nm). Furthermore, In-doping adversely affected the electrical properties of samples grown on (1 0 0) substrates while it enhanced those of (3 1 1)B samples. Two shallow defects were detected in all samples except for (3 1 1)B sample (In = 15 nm) where three shallow defects were observed. The presence of more shallow defects in this sample is evidenced by a red-shift in the absorption spectrum. It was concluded that sample (3 1 1)B (In = 15 nm) is best among all other samples and makes it more suitable for solar cell applications

    Dense sampling of ethnic groups within African countries reveals fine-scale genetic structure and extensive historical admixture

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    Previous studies have highlighted how African genomes have been shaped by a complex series of historical events. Despite this, genome-wide data have only been obtained from a small proportion of present-day ethnolinguistic groups. By analyzing new autosomal genetic variation data of 1333 individuals from over 150 ethnic groups from Cameroon, Republic of the Congo, Ghana, Nigeria, and Sudan, we demonstrate a previously underappreciated fine-scale level of genetic structure within these countries, for example, correlating with historical polities in western Cameroon. By comparing genetic variation patterns among populations, we infer that many northern Cameroonian and Sudanese groups share genetic links with multiple geographically disparate populations, likely resulting from long-distance migrations. In Ghana and Nigeria, we infer signatures of intermixing dated to over 2000 years ago, corresponding to reports of environmental transformations possibly related to climate change. We also infer recent intermixing signals in multiple African populations, including Congolese, that likely relate to the expansions of Bantu language-speaking peoples

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

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    Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

    SARS-CoV-2 Infection Is at Herd Immunity in the Majority Segment of the Population of Qatar.

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    BACKGROUND: Qatar experienced a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic that disproportionately affected the craft and manual worker (CMW) population, who comprise 60% of the total population. This study aimed to assess ever and/or current infection prevalence in this population. METHODS: A cross-sectional population-based survey was conducted during July 26 to September 09, 2020, to assess both anti-SARS-CoV-2 positivity through serological testing and current infection positivity through polymerase chain reaction (PCR) testing. Associations with antibody and PCR positivity were identified through regression analyses. RESULTS: The study included 2641 participants, 69.3% of whom were <40 years of age. Anti-SARS-CoV-2 positivity was 55.3% (95% CI, 53.3%-57.3%) and was significantly associated with nationality, geographic location, educational attainment, occupation, and previous infection diagnosis. PCR positivity was 11.3% (95% CI, 9.9%-12.8%) and was significantly associated with nationality, geographic location, occupation, contact with an infected person, and reporting 2 or more symptoms. Infection positivity (antibody and/or PCR positive) was 60.6% (95% CI, 58.6%-62.5%). The proportion of antibody-positive CMWs who had a prior SARS-CoV-2 diagnosis was 9.3% (95% CI, 7.9%-11.0%). Only seven infections were ever severe, and only 1 was ever critical-an infection severity rate of 0.5% (95% CI, 0.2%-1.0%). CONCLUSIONS: Six in every 10 CMWs in Qatar have been infected, suggestive of reaching the herd immunity threshold. Infection severity was low, with only 1 in every 200 infections progressing to be severe or critical. Only 1 in every 10 infections had been previously diagnosed, which is suggestive of mostly asymptomatic or mild infections
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