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PurposeThe goal of this study was to determine the accuracy of displacement‐encoding with stimulated echoes (DENSE) MRI in a tissue motion phantom with displacements representative of those observed in human brain tissue. MethodsThe phantom was comprised of a plastic shaft rotated at a constant speed. The rotational motion was converted to a vertical displacement through a camshaft. The phantom generated repeatable cyclical displacement waveforms with a peak displacement ranging from 92 µm to 1.04 mm at 1‐Hz frequency. The surface displacement of the tissue was obtained using a laser Doppler vibrometer (LDV) before and after the DENSE MRI scans to check for repeatability. The accuracy of DENSE MRI displacement was assessed by comparing the laser Doppler vibrometer and DENSE MRI waveforms. ResultsLaser Doppler vibrometer measurements of the tissue motion demonstrated excellent cycle‐to‐cycle repeatability with a maximum root mean square error of 9 µm between the ensemble‐averaged displacement waveform and the individual waveforms over 180 cycles. The maximum difference between DENSE MRI and the laser Doppler vibrometer waveforms ranged from 15 to 50 µm. Additionally, the peak‐to‐peak difference between the 2 waveforms ranged from 1 to 18 µm. ConclusionUsing a tissue phantom undergoing cyclical motion, we demonstrated the percent accuracy of DENSE MRI to measure displacement similar to that observed for in vivo cardiac‐induced brain tissue. 

Abstract Engineering education has increasingly embraced active learning techniques within a variety of curricula. In particular, project-based active learning techniques have a significant potential to enhance students' learning experience. In this study, we implemented project-based techniques in biomedical engineering (BME) classes, and we investigated the effects of active learning on students' self-efficacy as an effective predictor of students' academic persistence and their career decision-making. Differences in self-efficacy were compared across genders. A high level of internal consistency was observed for both academic and career-oriented scales, as determined by Cronbach's alpha values of 0.908 and 0.862, respectively. While average scores of all survey questions indicated improvement in students' academic and career-oriented self-efficacy measures, significant improvements were observed in “clearer vision of programming application in engineering” and “BME careers,” as well as in “expectation of success in a future BME career that involves developing medical devices” after the completion of the project-based activity (p = 0.002, 0.023, and 0.034, respectively). For two of the survey questions, female students reflected a significantly lower “self-confidence about understanding the most complex course material” as well as a significantly lower “willingness to have a future career in BME that involves intensive computer programing” as compared to male students (p = 0.035 and 0.024, respectively). We have further discussed possible explanations for the observed differences and multiple potential ways to enhance gender equality in STEM fields from a self-efficacy standpoint.