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Developing user-friendly learning platform tailored to illustrating the integrative nature of specific subjects can be very effective in enhancing the involvement of students in the classroom. The focus of this paper is twofold; first, highlighting a specific project from a teaching perspective for the design and implementation of a multipurpose experimental test facility for plug-in electric vehicle, renewable energy and energy storage management in the smart grid context. Second, proposing the application of this project as an interactive tool to assist in demonstrating the system behaviour, when teaching the new emerging subjects in power engineering courses particularly, Smart Grid. Indeed, the scope of the test facility with the developed simulation tool is specially structured and oriented to education, training and research studies, where problem-based learning can be easily implemented. The electrical test hardware in this design can be operated independently as a multipurpose experimental setup for plug-in electric vehicle. In addition, it can also be interconnected with a small size wind or photovoltaic system to facilitate a complete hybrid integrated platform for testing and model verification. A variety of illustrative examples are presented to show the features of the test facility with its operation and how the components of this facility were selected. Additionally, several test scenarios are depicted using the developed simulation tool, which cover the assessment of grid integration with its components in the event of unforeseen circumstances. A recommendation that can be drawn from this paper is to motivate academics who are actively involved in conducting research on smart grid, to make use of their hardware or software designs in the process of teaching and learning so that undergraduate students can get the opportunity of observation and experimentation. In this sense, suggestions for future work are proposed. [ABSTRACT FROM AUTHOR]

Purpose: To assess the inter-observer agreement of color duplex ultrasound of central vein stenosis in hemodialysis patients. Patients and methods: This prospective study was conducted on 35 hemodialysis patients with suspected central vein stenosis. All patients underwent color flow duplex examination of the subclavian, internal jugular and brachiocephalic veins in hemodialysis patients. Image analysis was performed by two reviewers for diameter reduction, peak venous velocity ratio, post-stenotic turbulent flow, waveform changes, and thrombus formation. Results: There was no significant difference between both observers for diameter reduction (p = 0.105) and for the mean peak systolic velocity ratio (p = 0.515). The overall inter-observer agreement of color duplex ultrasound of central vein stenosis was excellent (k = 0.84, percent agreement = 89.7%, P = 0.001). There was excellent inter-observer agreement of both reviewers for diameter reduction (k = 0.928, percent agreement = 97.14%), peak venous velocity ratio (k = 0.7, percent agreement = 85.7%), waveform changes (k = 0.62, percent agreement = 77.14%), post-stenotic turbulent flow (k = 0.866, percent agreement = 88.6%), thrombus formation (k = 1, percent agreement = 100%). Conclusion: We concluded that color duplex ultrasound is a reliable and reproducible method for diagnosis of central vein stenosis in hemodialysis patients. [ABSTRACT FROM AUTHOR]

Recent seismic events have raised concerns over the safety and vulnerability of reinforced concrete moment resisting frame “RC-MRF” buildings. The seismic response of such buildings is greatly dependent on the computational tools used and the inherent assumptions in the modelling process. Thus, it is essential to investigate the sensitivity of the response demands to the corresponding modelling assumption. Many parameters and assumptions are justified to generate effective structural finite element (FE) models of buildings to simulate lateral behaviour and evaluate seismic design demands. As such, the present study focuses on the development of reliable FE models with various levels of refinement. The effects of the FE modelling assumptions on the seismic response demands on the design of buildings are investigated. the predictive ability of a FE model is tied to the accuracy of numerical analysis; a numerical analysis is performed for a series of symmetric buildings in active seismic zones. The results of the seismic response demands are presented in a comparative format to confirm drift and strength limits requirements. A proposed model is formulated based on a simplified modeling approach, where the most refined model is used to calibrate the simplified model. [ABSTRACT FROM AUTHOR]

Background: A routine, multiphase, computed tomography (CT) protocol is associated with high radiation exposure to potential kidney donors. To reduce radiation exposure, several authors have suggested a reduction in the number of phases. Purpose: To evaluate a low-radiation-dose, dual-phase protocol (i.e. a protocol with an unenhanced phase and combined vascular and excretory phase) for the preoperative evaluation of potential renal donors. Material and Methods: Sixty-five potential renal donors were divided into two groups. The first group was scanned with a routine quadric-phase protocol (non-contrast, arterial, venous, and delayed), and the second group was scanned with a triple-phase protocol (dual phase protocol + venous phase). In the second group, we replaced CT angiography with a routine abdominal CT technique. In addition to the evaluation of renal arteries, veins, and excretory systems, the radiation dose of the suggested protocol was compared to that of the routine quadric-phase protocol. Results: The suggested protocol was efficient in the evaluation of renal arteries, veins, and excretory systems in all studied potential renal donors. Renal arteries were well visualized in the combined vascular excretory phase using the routine abdominal CT technique; no significant difference was noted when these results were compared to those obtained from the CT angiography used in the quadric-phase protocol. The mean effective radiation dose of our suggested dual-phase protocol was only 34% of the dose resulting from the routine quadric-phase protocol. Conclusion: Use of a low-radiation, dual-phase, CT protocol, which relied on both an unenhanced phase and a combined vascular and excretory phase, significantly reduced radiation dose. Furthermore, the proposed protocol provides adequate visualization of renal arteries and veins, and affords sufficient opacification of the urinary tract using improved acquisition triggering. [ABSTRACT FROM AUTHOR]

Background: Cardiac imaging is the cornerstone of the pretranscatheter aortic valve replacement (TAVR) assessment. Multi‐detector computed tomography (MDCT) is considered the conventional imaging modality. However, there is still no definitive gold standard. Targeted cohort of inoperable high‐risk patients with underlying comorbidities, particularly renal impairment, makes apparent the need for MDCT alternative. We aimed to demonstrate the correlation extent between MDCT and three‐dimensional transesophageal echocardiography (3DTEE) aortic annular area measures and to answer the question: Is 3DTEE a good alternative to MDCT? Methods: A systematic literature search and meta‐analysis were conducted to evaluate the degree of correlation and agreement between 3DTEE and MDCT aortic annular sizing. A thorough assessment of EMBASE, PubMed, and Cochrane Central Register of Controlled Trials (CENTRAL) was performed. All studies comparing 3DTEE and MDCT in relation to aortic annular sizing were included. Results: Thirteen studies were included (N = 1228 patients). A strong linear correlation was found between 3DTEE and MDCT measurements of aortic annulus area (r = 0.84, P < 0.001), mean perimeter (r = 0. 0.85, P < 0.001), and mean diameter (r = 0.80, P < 0.001). Bland–Altman plots revealed smaller mean 3DTEE values in comparison to MDCT for aortic annular area, the mean difference being −2.22 mm2 with 95% limits of agreement −12.79 to 8.36. Conclusion: Aortic annulus measurements obtained by 3DTEE demonstrated a high level of correlation with those evaluated by MDCT. This makes 3DTEE a feasible choice for aortic annulus assessment, with advantage of real time assessment, lack of contrast, and no radiation exposure. [ABSTRACT FROM AUTHOR]

Introduction: Foreign-body (FB) aspiration in the airway of children is a life-threatening clinical situation responsible for many deaths each year. The aim of this study was to evaluate the different clinical presentations, methods of diagnosis, types and complications of FB inhalation in the pediatric age group. Materials and Methods: The study included patients who presented with a definitive or suspicious history of FB aspiration. Detailed data for each patient were recorded concerning the age, sex, nature and site of the FB, presenting symptoms and signs, and radiological findings. Results: Fifty-six patients were enrolled in this study. The age of patients ranged from 6 months to 14 years, with a mean age of 4.5 years. Sixty percent of patients were under 3 years of age. The time interval between aspiration of foreign body and onset of diagnosis ranged from 2 hours to 5 months. Thirtyfour (60.7%) patients had normal chest X-ray findings, while opaque FB was seen in eight patients (14.3%). Signs of bronchitis were seen in five patients (9%), while pneumonia and atelectasis were seen in six (10.7%) and three cases (5.3%), respectively. Conclusion: FB aspiration is a life-threatening clinical situation, with children <3 years of age being most commonly affected. FB aspiration must be considered a matter of emergency, especially in the case of organic FBs. This study aimed to increase the awareness of laryngo-tracheo-bronchial FBs, as early diagnosis and management decrease the incidence of complications and make removal of aspirated FB easier. [ABSTRACT FROM AUTHOR]