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  1. This work-in-progress paper seeks to examine faculty choice of teaching strategies to improve students’ engineering self-efficacy [1], [2] (belief in one’s abilities to successfully accomplish tasks in engineering) as well as their reflections on the effectiveness of the teaching strategy. Increases in self-efficacy have been related to improved academic and career outcomes [3], especially for women in non-traditional fields such as engineering. The goal of the study is to determine simple yet effective strategies that can be implemented in engineering classrooms to improve self-efficacy. Seven engineering faculty members participated in a faculty learning community (FLC), a semester long program to learn about teaching strategies in each of the four areas of self-efficacy; mastery experiences (e.g., active learning, scaffolding), vicarious learning (e.g., guest lectures, peer mentors, group work), social persuasion (e.g., constructive feedback, positive self-talk), and emotional arousal (e.g., test anxiety, building rapport). The faculty then chose and implemented strategies in each of the four areas in one of their engineering courses. Monthly meetings of the FLC during implementation allowed faculty to share their experiences and suggestions for refinements in their teaching strategy. The paper examines the faculty member choice (why they chose to use particular strategies in their course) as well as their reflections on how well the strategy worked (impact on student learning vs ease of implementation). In addition, the paper examines in-class observations and student survey responses to determine if they felt a particular strategy was useful. The research seeks to identify strategies that faculty members chose and are viewed as effective by both the faculty and students. The presentation will seek additional feedback from the wider community on the effectiveness of teaching strategies to improve self-efficacy and future work will include the analysis of additional surveys that were administered to measure student self-efficacy with the goal of determining simple and effective strategies that can be implemented in engineering classrooms. 
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  2. This research evaluates the impact of switching college engineering courses from in-person instruction to emergency remote learning among engineering students at a university in the Midwest. The study aimed to answer the question: What were the concerns and perceived challenges students faced when traditional in-person engineering courses suddenly transitioned to remote learning? The goal of this study is to uncover the challenges students were facing in engineering online courses and to understand students’ concerns. Our findings can help improve teaching instruction to provide students with previously unavailable educational assistance for online engineering courses. We collected online survey responses during weeks 8 and 9 of the academic semester, shortly after the COVID-19 shutdown and emergency transition to remote learning in Spring 2020. The survey included two open-ended questions which inquired about students’ feedback about moving the class online, and one two-item scale which assessed students’ confidence in online engineering learning. Data analysis for the open-ended questions was guided by the theoretical framework - Social Cognitive Career Theory [1] that explores how context, person factors and social cognitions contribute to career goals, interests and actions. A phenomenological approach [2] was conducted to understand the experience of these students. Open coding and axial coding [2] methods were used to create initial categories then themes related to students' concerns and challenges. Data from the two-item scale was evaluated using descriptive statistics: means, standard deviations, and ranges. Four main themes with separate sub-categories emerged from the student responses: 1) Instructor’s ability to teach course online (Instructional limitations, Seeking help, Increased Workload), 2) Student’s ability to learn online (Time Management, Lower engagement and motivation, Harder to absorb material, Hard to focus, Worry about performance), 3) Difficulties outside of class (Technology issues), and 4) No concerns. Students seemed more concerned about their ability to learn the material (48% of responses) than the instructor’s ability to teach the material (36% of responses). The instructional limitations or lack of instructional support (22% of responses) and time management (12% of responses) were among the major concerns in the sub-categories. The results from two-item scale indicated participants' s confidence in their ability to master their classroom knowledge was at an intermediate level via online instruction (6/10), and participants' confidence in the instructor's ability to teach knowledge in online classes is moderate to high (7/10). The results align with the open-ended question response in which students were somewhat more concerned about their ability to learn than the instructor’s ability to teach. The themes and analysis will be a valuable tool to help institutions and instructors improve student learning experiences. 
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  3. null (Ed.)
    The outbreak of COVID-19 and sudden transition to remote learning brought many changes and challenges to higher education campuses across the nation. This paper evaluates the impact of the transition to remote learning on the engineering-related social cognitions of self-efficacy (belief in one’s abilities to successfully accomplish tasks in engineering) and outcome expectations (beliefs about the consequences of performing engineering behaviors). These social cognitions can be attributed to important academic and career outcomes, such as the development of STEM interests and goals (Lent et al., 2019) and may be especially important in the success of women in non-traditional fields such as engineering. As an extension to a NSF RIEF (Research Initiation in Engineering Formation) study evaluating engineering social cognitions, students in 8 engineering classes were surveyed at the beginning of Spring 2020 semester (N=224), shortly after the transition to remote learning (N = 190), and at the end of the semester (N=101). The classes surveyed included a common early engineering class at the sophomore level (Engineering Statics) and required junior level courses in different departments. The students were surveyed using reliable and validated instruments to measure engineering self-efficacy (Lent et al. 2005, Frantz et al. 2011), engineering outcome expectations (Lent et al. 2003, Lee et al. 2018), and engineering persistence intentions (Lent et al. 2003). The results show a gradual increase in the mean scores on the engineering self-efficacy and outcome expectation measures through the semester. Two tailed t-tests of matched participants showed no significance when comparing the data between the beginning and mid-semester surveys, as well as the mid-semester and end surveys. However, significance was found in the two engineering self-efficacy measures between the beginning and end of semester surveys. Results are compared across courses at different levels and across gender. Results indicate that despite the sudden change in instructional mode, students’ perceptions of engineering self-efficacy and outcome expectations showed a slight increase or no change. 
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  4. null (Ed.)
    Abstract Tropical precipitation change under global warming varies with season. The present study investigates the characteristics and cause of the seasonality in rainfall change. Diagnostically, tropical precipitation change is decomposed into thermodynamic and dynamic components. The thermodynamic component represents the wet-get-wetter effect and its seasonality is due mostly to that in the mean vertical velocity, especially in the monsoon regions. The dynamic component includes the warmer-get-wetter effect due to the spatial variations in sea surface temperature (SST) warming, while the seasonality is due to that of the climatological SST and can be largely reproduced by an atmospheric model forced with the monthly climatological SST plus the annual-mean SST warming pattern. In the eastern equatorial Pacific where the SST warming is locally enhanced; for example, rainfall increases only during the March–May season when the climatological SST is high enough for deep convection. To the extent that the seasonality of tropical precipitation change over oceans arises mostly from that of the climatological SST, the results support the notion that reducing model biases in climatology improves regional rainfall projections. 
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  5. Abstract

    Tropical climate response to greenhouse warming is to first order symmetric about the equator but climate models disagree on the degree of latitudinal asymmetry of the tropical change. Intermodel spread in equatorial asymmetry of tropical climate response is investigated by using 37 models from phase 6 of the Coupled Model Intercomparison Project (CMIP6). In the simple simulation with CO2increase at 1% per year but without aerosol forcing, this study finds that intermodel spread in tropical asymmetry is tied to that in the extratropical surface heat flux change related to the Atlantic meridional overturning circulation (AMOC) and Southern Ocean sea ice concentration (SIC). AMOC or Southern Ocean SIC change alters net energy flux at the top of the atmosphere and sea surface in one hemisphere and may induce interhemispheric atmospheric energy transport. The negative feedback of the shallow meridional overturning circulation in the tropics and the positive low cloud feedback in the subtropics are also identified. Our results suggest that reducing the intermodel spread in extratropical change can improve the reliability of tropical climate projections.

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  6. Summary

    Meiotic chromosome pairing between homoeologous chromosomes was reported in many nascent allopolyploids. Homoeologous pairing is gradually eliminated and replaced by exclusive homologous pairing in well‐established allopolyploids, an evolutionary process referred to as the diploidization of allopolyploids. A fundamental question of the diploidization of allopolyploids is whether and to what extent the DNA sequence variation among homoeologous chromosomes contribute to the establishment of exclusive homologous chromosome pairing.

    We developed aneuploid tetraploid maize lines that contain three copies of chromosome 10 derived from inbred lines B73 and H99. We were able to identify the parental origin of each copy of chromosome 10 in the materials using oligonucleotide‐based haplotype‐specific chromosome painting.

    We demonstrate that the two identical copies of chromosome 10 from H99 pair preferentially over chromosome 10 from B73 in different stages of prophase I and metaphase I during meiosis. Thus, homologous chromosome pairing is favored to partners with the most similar DNA sequences and can be discriminated based on cryptic sequence variation.

    We propose that innate preference of homologous chromosome pairing exists in nascent allopolyploids and serves as the first layer that would eventually block all homoeologous chromosome pairing in allopolyploids.

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  7. Abstract

    Protein ubiquitination regulates protein stability, cellular localization, and enzyme activity. Deubiquitinases catalyze the removal of ubiquitin from target proteins and reverse ubiquitination. USP13, a deubiquitinase, has been shown to regulate a variety of cellular responses including inflammation; however, the molecular regulation of USP13 has not been demonstrated. In this study, we revealed that USP13 is degraded in response to lipopolysaccharide (LPS) in Kupffer cells. USP13 levels are significantly decreased in inflamed organs, including liver tissues from septic mice. LPS reduces USP13 protein stability, not transcription, in Kupffer cells. Furthermore, LPS increases USP13 polyubiquitination. Inhibition of proteasome, but not lysosome or immunoproteasome, attenuates LPS‐induced USP13 degradation, suggesting USP13 degradation is mediated by the ubiquitin‐proteasome system. A catalytically inactive form of USP13 exhibits similar degree of degradation compared with USP13 wild‐type, suggesting that USP13 degradation is not dependent on its activity. Furthermore, USP13 degradation is dependent on new protein synthesis. Inhibition of c‐Jun N‐terminal kinase (JNK) attenuates USP13 degradation, indicating that JNK‐dependent new protein synthesis is necessary for USP13 degradation. This study reveals a molecular mechanism of regulation of USP13 degradation in Kupffer cells in response to bacterial endotoxin.

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