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Title: Jupyter Notebook for Reduced models of unidirectional flows in compliant rectangular ducts at finite Reynolds number
The Jupyter Notebook generates all the data and makes all the plots in the published paper "Reduced models of unidirectional flows in compliant rectangular ducts at finite Reynolds number"More>>
Purdue University Research Repository
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National Science Foundation
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  1. As our nation’s need for engineering professionals grows, a sharp rise in P-12 engineering education programs and related research has taken place (Brophy, Klein, Portsmore, & Rogers, 2008; Purzer, Strobel, & Cardella, 2014). The associated research has focused primarily on students’ perceptions and motivations, teachers’ beliefs and knowledge, and curricula and program success. The existing research has expanded our understanding of new K-12 engineering curriculum development and teacher professional development efforts, but empirical data remain scarce on how racial and ethnic diversity of student population influences teaching methods, course content, and overall teachers’ experiences. In particular, Hynes et al. (2017) note in their systematic review of P-12 research that little attention has been paid to teachers’ experiences with respect to racially and ethnically diverse engineering classrooms. The growing attention and resources being committed to diversity and inclusion issues (Lichtenstein, Chen, Smith, & Maldonado, 2014; McKenna, Dalal, Anderson, & Ta, 2018; NRC, 2009) underscore the importance of understanding teachers’ experiences with complementary research-based recommendations for how to implement engineering curricula in racially diverse schools to engage all students. Our work examines the experiences of three high school teachers as they teach an introductory engineering course in geographically and distinctly different raciallymore »diverse schools across the nation. The study is situated in the context of a new high school level engineering education initiative called Engineering for Us All (E4USA). The National Science Foundation (NSF) funded initiative was launched in 2018 as a partnership among five universities across the nation to ‘demystify’ engineering for high school students and teachers. The program aims to create an all-inclusive high school level engineering course(s), a professional development platform, and a learning community to support student pathways to higher education institutions. An introductory engineering course was developed and professional development was provided to nine high school teachers to instruct and assess engineering learning during the first year of the project. This study investigates participating teachers’ implementation of the course in high schools across the nation to understand the extent to which their experiences vary as a function of student demographic (race, ethnicity, socioeconomic status) and resource level of the school itself. Analysis of these experiences was undertaken using a collective case-study approach (Creswell, 2013) involving in-depth analysis of a limited number of cases “to focus on fewer "subjects," but more "variables" within each subject” (Campbell & Ahrens, 1998, p. 541). This study will document distinct experiences of high school teachers as they teach the E4USA curriculum. Participants were purposively sampled for the cases in order to gather an information-rich data set (Creswell, 2013). The study focuses on three of the nine teachers participating in the first cohort to implement the E4USA curriculum. Teachers were purposefully selected because of the demographic makeup of their students. The participating teachers teach in Arizona, Maryland and Tennessee with predominantly Hispanic, African-American, and Caucasian student bodies, respectively. To better understand similarities and differences among teaching experiences of these teachers, a rich data set is collected consisting of: 1) semi-structured interviews with teachers at multiple stages during the academic year, 2) reflective journal entries shared by the teachers, and 3) multiple observations of classrooms. The interview data will be analyzed with an inductive approach outlined by Miles, Huberman, and Saldaña (2014). All teachers’ interview transcripts will be coded together to identify common themes across participants. Participants’ reflections will be analyzed similarly, seeking to characterize their experiences. Observation notes will be used to triangulate the findings. Descriptions for each case will be written emphasizing the aspects that relate to the identified themes. Finally, we will look for commonalities and differences across cases. The results section will describe the cases at the individual participant level followed by a cross-case analysis. This study takes into consideration how high school teachers’ experiences could be an important tool to gain insight into engineering education problems at the P-12 level. Each case will provide insights into how student body diversity impacts teachers’ pedagogy and experiences. The cases illustrate “multiple truths” (Arghode, 2012) with regard to high school level engineering teaching and embody diversity from the perspective of high school teachers. We will highlight themes across cases in the context of frameworks that represent teacher experience conceptualizing race, ethnicity, and diversity of students. We will also present salient features from each case that connect to potential recommendations for advancing P-12 engineering education efforts. These findings will impact how diversity support is practiced at the high school level and will demonstrate specific novel curricular and pedagogical approaches in engineering education to advance P-12 mentoring efforts.« less
  2. Polynoidae Kinberg, 1856 has five branchiate genera: Branchipolynoe Pettibone, 1984, Branchinotogluma Pettibone, 1985, Branchiplicatus Pettibone, 1985, Peinaleopolynoe Desbruyères & Laubier, 1988, and Thermopolynoe Miura, 1994, all native to deep-sea, chemosynthetic-based habitats. Of these, Peinaleopolynoe has two accepted species; Peinaleopolynoe sillardi Desbruyères & Laubier, 1988 (Atlantic Ocean) and Peinaleopolynoe santacatalina Pettibone, 1993 (East Pacific Ocean). The goal of this study was to assess the phylogenetic position of Peinaleopolynoe , utilizing DNA sequences from a broad sampling of deep-sea polynoids. Representatives from all five branchiate genera were included, several species of which were sampled from near the type localities; Branchinotogluma sandersi Pettibone, 1985 from the Galápagos Rift (E/V “Nautilus”); Peinaleopolynoe sillardi from organic remains in the Atlantic Ocean; Peinaleopolynoe santacatalina from a whalefall off southern California (R/V “Western Flyer”) and Thermopolynoe branchiata Miura, 1994 from Lau Back-Arc Basin in the western Pacific (R/V “Melville”). Phylogenetic analyses were conducted using mitochondrial (COI, 16S rRNA, and CytB) and nuclear (18S rRNA, 28S rRNA, and H3) genes. The analyses revealed four new Peinaleopolynoe species from the Pacific Ocean that are formally described here: Peinaleopolynoe orphanae Hatch & Rouse, sp. nov. , type locality Pescadero Basin in the Gulf of California, Mexico (R/V “Western Flyer”); Peinaleopolynoemore »elvisi Hatch & Rouse, sp. nov. and Peinaleopolynoe goffrediae Hatch & Rouse, sp. nov. , both with a type locality in Monterey Canyon off California (R/V “Western Flyer”) and Peinaleopolynoe mineoi Hatch & Rouse, sp. nov. from Costa Rica methane seeps (R/V “Falkor”). In addition to DNA sequence data, the monophyly of Peinaleopolynoe is supported by the presence of ventral papillae on segments 12–15. The results also demonstrated the paraphyly of Branchinotogluma and Lepidonotopodium Pettibone, 1983 and taxonomic revision of these genera is required. We apply the subfamily name Lepidonotopodinae Pettibone 1983, for the clade comprised of Branchipolynoe , Branchinotogluma , Bathykurila , Branchiplicatus , Lepidonotopodium , Levensteiniella Pettibone, 1985, Thermopolynoe , and Peinaleopolynoe .« less
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  4. Abstract
    The COVID-19 pandemic has dramatically altered family life in the United States. Over the long duration of the pandemic, parents had to adapt to shifting work conditions, virtual schooling, the closure of daycare facilities, and the stress of not only managing households without domestic and care supports but also worrying that family members may contract the novel coronavirus. Reports early in the pandemic suggest that these burdens have fallen disproportionately on mothers, creating concerns about the long-term implications of the pandemic for gender inequality and mothers’ well-being. Nevertheless, less is known about how parents’ engagement in domestic labor and paid work has changed throughout the pandemic, what factors may be driving these changes, and what the long-term consequences of the pandemic may be for the gendered division of labor and gender inequality more generally. <br /><br />The Study on U.S. Parents’ Divisions of Labor During COVID-19 (SPDLC) collects longitudinal survey data from partnered U.S. parents that can be used to assess changes in parents’ divisions of domestic labor, divisions of paid labor, and well-being throughout and after the COVID-19 pandemic. The goal of SPDLC is to understand both the short- and long-term impacts of the pandemic for the genderedMore>>
  5. Ascospores generated during sexual reproduction are the primary inoculum for the wheat scab fungus Fusarium graminearum. Purine metabolism is known to play important roles in fungal pathogens but its lifecycle stage-specific regulation is unclear. By characterizing the genes involved in purine de novo and salvage biosynthesis pathways, we showed that de novo syntheses of inosine, adenosine and guanosine monophosphates (IMP, AMP and GMP) are important for vegetative growth, sexual/asexual reproduction, and infectious growth, whereas purine salvage synthesis is dispensable for these stages in F. graminearum. Addition of GMP rescued the defects of the Fgimd1 mutant in vegetative growth and conidiation but not sexual reproduction, whereas addition of AMP rescued all of these defects of the Fgade12 mutant, suggesting that the function of de novo synthesis of GMP rather than AMP is distinct in sexual stages. Moreover, Acd1, an ortholog of AMP deaminase, is dispensable for growth but essential for ascosporogenesis and pathogenesis, suggesting that AMP catabolism has stage-specific functions during sexual reproduction and infectious growth. The expression of almost all the genes involved in de novo purine synthesis is downregulated during sexual reproduction and infectious growth relative to vegetative growth. This study revealed that F. graminearum has stage-specific regulation ofmore »purine metabolism during infectious growth and sexual reproduction.« less