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Atherosclerosis, a progressive disease of the large arteries, is the primary cause of heart disease, and stroke. Endothelial cell (EC) dysfunction precedes the development of atherosclerosis. ECs are mainly affected by three mechanical factors; pressure from pulse, shear stress from blood flow, and strain due to the elasticity of the blood vessel. ECs require these mechanical factors to function at optimal levels. Deviation from these levels can result in damage to ECs and lead to disease initiation. An additional factor for EC dysfunction is increased wall stiffness due to the non-linear mechanical properties of the arterial wall. As the main coronaries are located on the epicardium, these vessels stretch and twist with each heartbeat, resulting in a non-uniform spatial distribution in strain and thus in wall stiffness. Therefore, the purpose of this investigation was to develop a non-invasive method to characterize local strain stiffness responsible for changes in EC function. To this end, a commercially available digital image correlation (DIC) was used to characterize local strain measurements under physiological conditions. Sylgard 184 was used to create synthetic models with varying elastic modulus that mimic arterial geometry. The models were then coated with micron size particles and local strain measurements could then be estimated on a Sylgard tube to an approximate accuracy of 2.1%. These preliminary results demonstrate the potential of such a system to characterize local strain undergoing arterial hemodynamics., INTRODUCTION Atherosclerosis is a progressive disease of the large arteries [1]. It is the primary cause of heart disease and stroke, and is the underlying cause of about fifty percent [...]

The 2 recommended lung cancer staging strategies, mediastinal nodal staging and endosonography, are compared. The studies have shown that a staging strategy combining endosonography and surgical staging when compared with surgical staging alone has resulted in greater sensitivity for mediastinal nodal metastases and fewer unnecessary thoracotomies among patients with non-small cell lung cancer (NSCLC).

Objective: Food literacy (FL) and nutrition literacy (NL) are concepts that can help individuals to navigate the current food environment. Building these skills and knowledge at a young age is important for skill retention, confidence in food practices and supporting lifelong healthy eating habits. The objectives of this systematic review were to: (i) identify existing tools that measure FL and NL among children and/or adolescents and (ii) describe the psychometric properties. Design: A 4-phase protocol was used to systematically retrieve articles. The search was performed in May 2021. Study characteristics and psychometric properties were extracted, and a narrative synthesis was used to summarise findings. Risk of bias was assessed using the COSMIN checklist. Setting: Six databases were searched to identify current tools. Participants: Children (2–12 years) and adolescents (13–18 years) participated in this study. Results: Twelve tools were identified. Three tools measured FL, 1 tool measured NL, 4 tools measured both FL and NL, and 4 tools measured subareas of NL—more specifically, critical NL, food label and menu board literacy. Most tools were self-reported, developed based on a theoretical framework and assessed some components of validity and/or reliability for a specific age and ethnic group. The majority of tools targeted older children and adolescents (9–18 years of age), and one tool targeted preschoolers (3–6 years of age). Conclusions: Most widely used definitions of FL and NL do not acknowledge life-stage specific criterion. Continued efforts are needed to develop a comprehensive definition and framework of FL and NL appropriate for children, which will help inform future assessment tools. [ABSTRACT FROM AUTHOR]

Reflective thinking and learning skills are essential for engineers in the knowledge economy. This paper describes an approach to develop these and other transferable skills through individual and collaborative reflective learning using open-source software. The learning activities and an open-source e-portfolio system called Dotfolio were tested by freshman engineering students. Findings from a survey-based study, which investigated students' beliefs about reflective learning and their expectations and experiences related to the task and open-source tool, are reported. From the beginning of the semester the students understood the significance of reflective learning and chose to work with the tool. However, they were less positive about the collaboration with peers during this activity. At the end of the semester, students were significantly more positive about the tool, but even more negative about the collaboration. The main problems encountered by the tutors and learners were plagiarism and a tension between the privacy of students' reflections and knowledge sharing. The open-source modular architecture allowed for the use of student and tutor feedback for the addition of new features that addressed their concerns. Index Terms--e-learning, e-portfolio, engineering, higher education, open source, reflective learning, undergraduate level.

Atherosclerosis is the leading cause of heart attacks and strokes in the U.S., accounting for up to 800,000 deaths annually. Metallic stents are the number one choice to re-open clogged arteries but problems caused by stent fracturing are hindering their effectiveness. This is especially common in the superficial femoral artery and is reported to be more widespread of a problem in this area of the body than others. This high rate of fracturing is believed to be caused by the unique combination of biomechanical forces that the artery experiences in day to day activities. Although standalone failure tests are performed quite regularly on stents, the problem still continues. A different approach is needed to identify the specific cause of failure in these stents and its impact on the biological performance. Therefore, the purpose of this project was to design and build a medical testing device that can subject a stent to the axial and torsional biomechanical forces experienced by stents deployed in femoral arteries. The system was developed by utilizing a linear actuator to mimic the axial forces, and a servo motor to mimic torsional forces. All of these components were controlled using a custom LABVIEW[C] interface. The system is capable of linear movement at a rate of one inch per second and can deliver torsional force at any angle between zero and ninety degrees. The developed novel system is thus capable of mimicking a wide range of motion to better elucidate the relationship between biomechanical factors and device durability. Keywords: Stent Mechanics, Axial, Torsional, Superficial Femoral Artery, INTRODUCTION With atherosclerosis accounting for 1 in 4 of every death in the U.S. [1], the need for rigorous testing on stents deployed in the superficial femoral artery (SFA) is [...]

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Byline: Rafael A. Calvo, Nicholas L. Carroll, Robert A. Ellis This paper discusses the design, development and use of a portal system for the administration and integration of teaching activities to improve their effectiveness and coherence. The system provides: a knowledge repository of syllabus and instructional design of courses in a university; functionality that enables staff to perform administrative activities online; a collaboration environment supporting the knowledge repository. The three types of functionality are integrated to benefit key stakeholders: students, who can benefit from a better understanding of the relationships between courses; teachers, who are able to see a reduction in their administration activities; and administrators, who can use the system as a reporting tool.