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Computer-based testing is a powerful tool for scaling exams in large lecture classes. The decision to adopt computer-based testing is typically framed as a tradeoff in terms of time; time saved by auto-grading is reallocated as time spent developing problem pools, but with significant time savings. This paper seeks to examine the tradeoff in terms of accuracy in measuring student understanding. While some exams (e.g., multiple choice) are readily portable to a computer-based format, adequately porting other exam types (e.g., drawings like FBDs or worked problems) can be challenging. A key component of this challenge is to ask “What is the exam actually able to measure?” In this paper the authors will provide a quantitative and qualitative analysis of student understanding measurements via computer-based testing in a sophomore level Solid Mechanics course. At Michigan State University, Solid Mechanics is taught using the SMART methodology. SMART stands for Supported Mastery Assessment through Repeated Testing. In a typical semester, students are given 5 exams that test their understanding of the material. Each exam is graded using the SMART rubric which awards full points for the correct answer, some percentage for non-conceptual errors, and zero points for a solution that has a conceptual error. Every exam is divided into four sections; concept, simple, average, and challenge. Each exam has at least one retake opportunity, for a total of 10 written tests. In the current study, students representing 10% of the class took half of each exam in Prairie Learn, a computer-based auto-grading platform. During this exam, students were given instant feedback on submitted answers (correct or incorrect) and given an opportunity to identify their mistakes and resubmit their work. Students were provided with scratch paper to set up the problem and work out solutions. After the exam, the paper-based work was compared with the computer submitted answers. This paper examines what types of mistakes (conceptual and non-conceptual) students were able to correct when feedback was provided. The answer is dependent on the type and difficulty of the problem. The analysis also examines whether students taking the computer-based test performed at the same level as their peers who took the paper-based exams. Additionally, student feedback is provided and discussed. 

Background Hypertension drives myocardial remodeling, leading to changes in structure, composition and mechanical behavior, including residual stress, which are linked to heart disease progression in a gender-specific manner. Emerging therapies are also targeting constituent-specific pathological features. All previous studies, however, have characterized remodeling in the intact tissue, rather than isolated tissue constituents, and did not include sex as a biological variable. Objective In this study we first identified the contribution of collagen fiber network and myocytes to the myocardial residual stress/strain in Dahl-Salt sensitive rats fed with high fat diet. Then, we quantified the effect of hypertension on the remodeling of the left ventricle (LV), as well as the existence of sex-specific remodeling features. Methods We performed mechanical tests (opening angle, ring-test) and histological analysis on isolated constituents and intact tissue of the LV. Based on the measurements from the tests, we performed a stress analysis to evaluate the residual stress distribution. Statistical analysis was performed to identify the effects of constituent isolation, elevated blood pressure, and sex of the animal on the experimental measurements and modeling results. Results Hypertension leads to reduced residual stress/strain in the intact tissue, isolated collagen fibers, and isolated myocytes in male and female rats. Collagen remains the largest contributor to myocardial residual stress in both normotensive and hypertensive animals. We identified sex-differences in both hypertensive and normotensive animals. Conclusions We observed both constituent- and sex-specific remodeling features in the LV of an animal model of hypertension.