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  1. The purpose of this work was to test the inter-rater reliability (IRR) of a rubric used to grade technical reports in a senior-level chemical engineering laboratory course that has multiple instructors that grade deliverables. The rubric consisted of fifteen constructs that provided students detailed guidance on instructor expectations with respect to the report sections, formatting and technical writing aspects such as audience, context and purpose. Four student reports from previous years were scored using the rubric, and IRR was assessed using a two-way mixed, consistency, average-measures intraclass correlation (ICC) for each construct. Then, the instructors met as a group to discuss their scoring and reasoning. Multiple revisions were made to the rubric based on instructor feedback and constructs rated by ICC as poor. When fair or poor constructs were combined, the ICCs improved. In addition, the overall score construct continued to be rated as excellent, indicating that while different instructors may have variation at the individual construct level, they evaluate the overall quality of the report consistently. A key learning from this process was the importance of the instructor discussion around their reasoning for the scores and the importance of an ‘instructor orientation’ involving discussion and practice using the rubrics in the case of multiple instructors or a change in instructors. The developed rubric has the potential for broad applicability to engineering laboratory courses with technical writing components and could be adapted for alternative styles of technical writing genre. 
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    Free, publicly-accessible full text available June 1, 2024
  2. Laboratory experimentation is a key component of the development of professional engineers. However, experiments conducted in chemical engineering laboratory classes are commonly more prescriptive than the problems faced by practicing engineers, who have agency to make consequential decisions across the experiment and communication of results. Thus, understanding how experiments in laboratory courses vary in offering students opportunities to make such decisions, and how students navigate higher agency learning experiences is important for preparing graduates ready to direct these practices. In this study, we sought to answer the following research question: What factors are measured by the Consequential Agency in Laboratory Experiments survey? To better understand student perceptions of their agency in relation to laboratory experiments, developed an initial version of the Consequential Agency in Laboratory Experiments survey, following research-based survey development guidelines. We implemented it in six upper-division laboratory courses across two universities. We used exploratory factor analysis to investigate the validity of the data from the survey for measuring relevant constructs of authenticity, agency in specific domains, responsibility, and opportunity to make decisions. We found strong support for items measuring agency as responsibility, authenticity, agency in the communication domain, agency in the experimental design domain, and opportunity to make decisions. These findings provide a foundation for developing a more precise survey capable of measuring agency across various laboratory experiment practices. Such a survey will enable future studies that investigate the impacts of increasing agency in just one domain versus in several. In turn, this can aid faculty in developing higher agency learning experiences that are more feasible to implement, compared to authentic research experiences. 
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    Free, publicly-accessible full text available July 1, 2024
  3. Laboratory experimentation is a key component of the development of professional engineers. However, experiments conducted in chemical engineering laboratory classes are commonly more prescriptive than the problems faced by practicing engineers, who have agency to make consequential decisions across the experiment and communication of results. Thus, understanding how experiments in laboratory courses vary in offering students opportunities to make such decisions, and how students navigate higher agency learning experiences is important for preparing graduates ready to direct these practices. In this study, we sought to answer the following research question: What factors are measured by the Consequential Agency in Laboratory Experiments survey? To better understand student perceptions of their agency in relation to laboratory experiments, developed an initial version of the Consequential Agency in Laboratory Experiments survey, following research-based survey development guidelines. We implemented it in six upper-division laboratory courses across two universities. We used exploratory factor analysis to investigate the validity of the data from the survey for measuring relevant constructs of authenticity, agency in specific domains, responsibility, and opportunity to make decisions. We found strong support for items measuring agency as responsibility, authenticity, agency in the communication domain, agency in the experimental design domain, and opportunity to make decisions. These findings provide a foundation for developing a more precise survey capable of measuring agency across various laboratory experiment practices. Such a survey will enable future studies that investigate the impacts of increasing agency in just one domain versus in several. In turn, this can aid faculty in developing higher agency learning experiences that are more feasible to implement, compared to authentic research experiences. 
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    Free, publicly-accessible full text available July 1, 2024
  4. Laboratory experimentation is a key component of the development of professional engineers. However, experiments conducted in chemical engineering laboratory classes are commonly more prescriptive than the problems faced by practicing engineers, who have agency to make consequential decisions across the experiment and communication of results. Thus, understanding how experiments in laboratory courses vary in offering students opportunities to make such decisions, and how students navigate higher agency learning experiences is important for preparing graduates ready to direct these practices. In this study, we sought to answer the following research questions: How do students perceive their agency in course-based undergraduate research experiences? What factors are measured by the Consequential Agency in Laboratory Experiments survey? To better understand student perceptions of their agency in relation to laboratory experiments, we first conducted a case study of a course-based research experience (CURE) in a senior-level chemical engineering laboratory course. We then surveyed six upper-division laboratory courses across two universities using an initial version of the Consequential Agency in Laboratory Experiments survey. We used exploratory factor analysis to investigate the validity of the data from the survey for measuring relevant constructs of authenticity, agency in specific domains, responsibility, and opportunity to make decisions. We found that with instructional support, students in the CURE recognized that failure could itself provide opportunities for learning. They valued having the agency to make consequential decisions, even when they also found the experience challenging. We also found strong support for items measuring agency as responsibility, authenticity, agency in the communication domain, agency in the experimental design domain, and opportunity to make decisions. These findings give us insight into the value of higher agency laboratory experiments, and they provide a foundation for developing a more precise survey capable of measuring agency across various laboratory experiment practices. Such a survey will enable future studies that investigate the impacts of increasing agency in just one domain versus in several. In turn, this can aid faculty in developing higher agency learning experiences that are more feasible to implement, compared to CUREs. 
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    Free, publicly-accessible full text available July 1, 2024
  5. Free, publicly-accessible full text available March 1, 2024
  6. Abstract

    Social relationships have physiological impacts. Here, we investigate whether loss of the mother/offspring relationship has lasting effects on fecal glucocorticoid metabolite (fGCM) concentrations in wild African elephant orphans several years following their mothers’ deaths. We find no difference in fGCM concentrations between orphans and nonorphans, but find lower fGCM concentrations in elephants with more age mates in their family. We also unexpectedly identify lower concentrations in orphans without their natal family versus nonorphans and natal orphans, which we speculate may be due to the development of hypocortisolism following a prolonged period without familial support. An index of plant productivity (i.e. food) shows the largest correlation with fGCM concentrations. Our findings indicate no lasting differences in glucocorticoid concentrations of surviving orphan elephants who are with their family, suggest the presence of age mates may reduce glucocorticoid concentrations in elephants, and emphasize that basic survival needs are the primary regulators of the stress response.

     
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  7. We document the smaller average employment size and lower financial access of Black-owned businesses compared to White-owned businesses. Controlling for other characteristics, we find that observed differences in finance account for 60 percent of the 11.3 percent racial gap in number of employees; differences in returns account for 103 percent. The results imply that if both the levels and returns on finance were equalized across races, then Black-owned firms would be 18.4 percent larger than their actual size. Equalizing financial factors alone would reverse the firm size gap so that Black-owned firms would be larger than White-owned firms by 7.1 percent. 
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  8. In contrast to the dynamic treatment of other aspects of the curriculum, and despite being at the center of chemical engineering education, laboratory experiments have remained largely unchanged for decades. To characterize the potential impact changes to laboratory courses could have, we explored student perceptions across a department and characterized the kinds of opportunities students have to use their agency in these courses across universities. We used a survey to measure students’ sense of agency across several laboratory courses in a chemical engineering department. We found students in laboratory courses across the chemical engineering laboratory sequence, including those engaged in authentic course-based research did not perceive the experiments as agentive or authentic. We infer students draw upon abundant low-agency experiences in laboratory experiments. We report on the agency that instructors report students possessing across two chemical engineering departments to understand variation across institutions. Maximizing learning in laboratory courses may hinge on clearer communication about authentic experiments or systematic redesign of earlier courses. 
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  9. Structured illumination microscopy (SIM) reconstructs optically-sectioned images of a sample from multiple spatially-patterned wide-field images, but the traditional single non-patterned wide-field images are more inexpensively obtained since they do not require generation of specialized illumination patterns. In this work, we translated wide-field fluorescence microscopy images to optically-sectioned SIM images by a Pix2Pix conditional generative adversarial network (cGAN). Our model shows the capability of both 2D cross-modality image translation from wide-field images to optical sections, and further demonstrates potential to recover 3D optically-sectioned volumes from wide-field image stacks. The utility of the model was tested on a variety of samples including fluorescent beads and fresh human tissue samples.

     
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