Work in Progress: Rigorously Assessing the Anecdotal Evidence of Increased Student Persistence in an Active, Blended, and Collaborative Mechanical Engineering Environment

This work in progress describes an ongoing study of an active, blended, and collaborative (ABC) course environment used in a core mechanical engineering course. This course has built on the growing body of literature citing active learning (Freeman et al., 2014), blended structures (Bowen & Ithaka, 2012), and collaborative engagement (Jeong & Chi, 2007) as positive influences on college and university science, technology, engineering, and math (STEM) outcomes. For the last six years, “Dynamics”, a core mechanical engineering course at a large public university, has utilized in-class activities, frequently-watched problem-solving videos, and a collaborative blog space to realize an ABC environment. On one key metric of course success, the rate of students who drop, fail, or withdraw from (DFW), the course has experienced near-constant improvements since the ABC structures were introduced. In this study, the authors utilize rigorous longitudinal methods to determine whether this drop in DFW rates can be directly attributed to increased implementation of ABC features. The authors hypothesize that as instructors become accustomed to the ABC environment and increase the level of in-class activity, use of blended resources, and collaboration, the likelihood of DFW in each subsequent year would drop. However, in the same time period, each subsequent class entered with higher levels of performance on proxy measures for prior knowledge. We therefore build a logistic regression model to predict individual-level DFW and determine whether the anecdotal drops in DFW that we observe can be attributed to the expansion of the ABC environment. More specifically, we predict likelihood of DFW based on students’ prior knowledge (grade in the preceding course, SAT math score), key demographics (gender, race/ethnicity), the semester and year they took Dynamics, their instructor, their year in school, and their major. We test for year fixed effects {year_t, t = 1, 2, ..., 7} to determine whether odds ratios for DFW consistently and significantly decrease over time. We also test for instructor effects, in particular for differences between the instructors who were involved in the design and development of the ABC environment and more independent instructors who only partially implemented the ABC course components. We anticipate results that will provide more rigorous, less biased, and efficient estimates for the individual- and class-level components that explain variance in DFW rates. These results would provide immediate implications for the next phase of our work, as we assess the next on-term implementation of the course in 2016. Our findings would also have long-term significance for other classes in mechanical engineering and related disciplines and for classes at other institutions that are considering implementing a comprehensive ABC learning environment

Transforming a Dynamics Course to an Active, Blended, and Collaborative Format: Focus on the Faculty

Mechanical engineering programs are increasingly applying educational research by transforming courses to be more interactive and to use a blend of online and face-to-face materials. However, the process of an existing course adopting these new practices is not well studied, and even less is understood about the faculty experience from on-boarding to delivery of a new curriculum or pedagogy. In this study, we follow the translation of an active, blended, and collaborative (ABC) curriculum for a core dynamics course from a large public university (where the ABC curriculum was developed) to a small private university. We use interpretive phenomenology to focus on the lived experience of the instructor newly implementing these course materials, format, and pedagogical approach. Specifically, we address the following research questions: (1) What is the lived experience of a mechanical engineering instructor at a different institution as she adopts and adapts the provided materials and format? (2) How does the experience of this instructor evolve throughout the semester? We use rich qualitative data to understand the experience of the instructor, who taught this course in its prior format and, in Fall 2015, taught the “off-term” core dynamics course via the new ABC structure. Through weekly reflection prompts, pre- and post-semester interviews, and supplementary process data (e.g., notes of weekly meetings between the new implementer and ABC team at the large public university), we describe and characterize the multi-faceted instructor experience. This includes her experience learning about the curriculum and online tools, implementing the class and adjusting her teaching practices, and assessing her students’ engagement with the course and understanding of dynamics concepts. Our findings suggest further areas of inquiry for studies of faculty practices around curriculum adoption, including probing opportunities for cross-institutional collaborations to share materials and transform courses, interrogating variation in mechanical engineering department and student cultures, and studying sources of faculty development and support throughout the course transformation process

Analyzing an Abbreviated Dynamics Concept Inventory and Its Role as an Instrument for Assessing Emergent Learning Pedagogies

The Dynamics Concept Inventory (DCI) is a validated assessment tool commonly used to evaluate student growth within core, gateway-level mechanics courses. This research explored the evaluative use of this tool within the context of Freeform – an emergent course system that buttresses active class meetings with blended and collaborative virtual learning environments, themselves founded upon extensive multimedia content and interactive forums – at Purdue University. The paper specifically considers a number of related issues including: (i) the thoughtful development (via expert content validation) and statistical reliability of an abbreviated DCI instrument, which is more amenable to in-class implementation than the much longer full DCI; (ii) the correlation of abbreviated-DCI performance with exam scores and final course grades for a dynamics course using the Freeform framework with an emphasis on both conceptual understanding and traditional problem-solving skills; and (iii) various inter-section performance metrics in a preliminary study on how an implementation of the abbreviated-DCI may help elucidate the impact of the instructor within the Freeform framework. The results of these analyses supported the validity and reliability of the abbreviated DCI tool, and demonstrated its usefulness in a formal research setting. The preliminary study suggested that the Freeform framework might normalize differences in instructor pedagogical choices and student performance across class sections. These findings indicate that the abbreviated DCI holds promise as a research instrument and lay the groundwork for future inquiry into the impact of the Freeform instructional framework on students and instructors alike

The Changing Landscape for Stroke\ua0Prevention in AF: Findings From the GLORIA-AF Registry Phase 2

Background GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation) is a prospective, global registry program describing antithrombotic treatment patterns in patients with newly diagnosed nonvalvular atrial fibrillation at risk of stroke. Phase 2 began when dabigatran, the first non\u2013vitamin K antagonist oral anticoagulant (NOAC), became available. Objectives This study sought to describe phase 2 baseline data and compare these with the pre-NOAC era collected during phase 1. Methods During phase 2, 15,641 consenting patients were enrolled (November 2011 to December 2014); 15,092 were eligible. This pre-specified cross-sectional analysis describes eligible patients\u2019 baseline characteristics. Atrial fibrillation disease characteristics, medical outcomes, and concomitant diseases and medications were collected. Data were analyzed using descriptive statistics. Results Of the total patients, 45.5% were female; median age was 71 (interquartile range: 64, 78) years. Patients were from Europe (47.1%), North America (22.5%), Asia (20.3%), Latin America (6.0%), and the Middle East/Africa (4.0%). Most had high stroke risk (CHA2DS2-VASc [Congestive heart failure, Hypertension, Age  6575 years, Diabetes mellitus, previous Stroke, Vascular disease, Age 65 to 74 years, Sex category] score  652; 86.1%); 13.9% had moderate risk (CHA2DS2-VASc = 1). Overall, 79.9% received oral anticoagulants, of whom 47.6% received NOAC and 32.3% vitamin K antagonists (VKA); 12.1% received antiplatelet agents; 7.8% received no antithrombotic treatment. For comparison, the proportion of phase 1 patients (of N = 1,063 all eligible) prescribed VKA was 32.8%, acetylsalicylic acid 41.7%, and no therapy 20.2%. In Europe in phase 2, treatment with NOAC was more common than VKA (52.3% and 37.8%, respectively); 6.0% of patients received antiplatelet treatment; and 3.8% received no antithrombotic treatment. In North America, 52.1%, 26.2%, and 14.0% of patients received NOAC, VKA, and antiplatelet drugs, respectively; 7.5% received no antithrombotic treatment. NOAC use was less common in Asia (27.7%), where 27.5% of patients received VKA, 25.0% antiplatelet drugs, and 19.8% no antithrombotic treatment. Conclusions The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in Asia and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701

Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

Beyond Aggregated Data: A Study of Group Differences in Conceptual Understanding and Resource Usage in an Undergraduate Dynamics Course

As pedagogical innovations continue to be developed and adopted in engineering education, it is important to understand how these innovations affect the students’ experiences and achievements. A common data analysis practice when evaluating educational innovations is to aggregate the data from all of the students together. However, this data aggregation inherently biases the results toward the characteristics of the dominant student group, leaving the experiences of minority groups largely unexplored. In this dissertation, I investigate the students’ experiences and achievements in an undergraduate dynamics course, and I intentionally use analysis methods that disaggregate the data to better understand the behaviors and performance of smaller subgroups of students, not just the majority. This dissertation presents three studies that examine: 1) the validity, reliability, and fairness of a standardized set of conceptual questions on the final exam, with a focus on gender fairness, 2) how and why the students use the available resources, and 3) how the students’ holistic resource usage patterns relate to their academic achievement. My motivation for choosing these studies was that conceptual assessments and customized resources are two key components of the learning environment for the dynamics course. However, the quality of the conceptual exam questions used for the course had yet to be evaluated. Similarly, the learning environment for the course incorporates many customized resources, including a custom-written “lecturebook” (a hybrid of a textbook and a workbook) and an extensive online library of videos, but little was known about how the students used these resources, or how the students’ pattern of resource usage related to their performance in the course. The first study in this dissertation used multiple-group confirmatory factor analysis to investigate item-level gender bias in a 12-item Abbreviated Dynamics Concept Inventory (aDCI), which was a set of standardized conceptual questions included on the final exam. The results suggested that two items were slightly biased against women, with stereotypically-masculine contexts and content as possible sources of the bias. The bias in the aDCI items likely unfairly lowered some women’s final exam scores, highlighting the need for engineering educators to consider the fairness of their assessments. The second study used a cluster analysis of survey responses to identify nine archetypical patterns of resource usage, all of which differed from the average resource-usage pattern of the aggregated sample. An analysis of forty-four student interviews, organized by resource-usage cluster, determined that students exhibited their resource-usage behaviors largely because of how they perceived the resource’s availability, accessibility, and quality. The results illustrate that there is no “typical” way in which the students used the resources, so it is important for instructors to consider a wide array of usage behaviors when designing a course’s learning environment and resources. The third study utilized a multiple regression analysis to find that on average a student’s resource-usage pattern is not related to their achievement when controlling for many other demographic, cognitive, and non-cognitive factors that can affect resource usage and performance. However, two individual resource-usage patterns were significantly related to achievement. Students who primarily used their lecturebook and their peers for support performed better than their similar peers in other resource-usage clusters. Conversely, students who rarely used their lecturebook had lower course grades than their peers. Drawing from the results of the second study, general study-habit suggestions for the students in the course were extracted from the qualitative themes found in the interviews of the students in these two clusters

Minimal-Sensing, Passive Force Identification Techniques for a Composite Structural Missile Component

Structural health monitoring systems are often limited to the use of one sensor due to cost, complexity, and weight restrictions. Therefore, there is a need to develop load and damage identification techniques that utilize only one sensor. Two passive force estimation techniques are investigated in this work. The techniques focus on either the shape or the amplitude of the magnitude of the applied force in the frequency domain. Both techniques iteratively reduce an underdetermined set of equations of motion into many overdetermined systems of equations to solve for the force estimates. The techniques are shown to locate and quantify impulsive impacts with over 97% accuracy and non-impulsive impacts with at least 87% accuracy. A filament-wound rocket motor casing is used as a test structure. Impacts not acting at a specific input degree of freedom are also accurately located depending on the distance away from the modeled input degrees of freedom, and damaging impact forces are quantified by making assumptions about the impulsive nature of the applied force