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This qualitative research study is part of a larger NSF-funded project entitled "Cogenerative Development of Culturally Relevant Pedagogical Guidelines for Computer Science and Computational Thinking in High Schools." During Year 1 of the project, qualitative semi- structured interviews were conducted with 26 high school students to better understand the challenges and barriers to enrollment in and/or engagement/success in Computer Science courses in high school. A grounded theory approach was used, given the exploratory nature of the study. Students were selected from three regional high schools and had to meet at least one of the criteria associated with underrepresented students in Computer Science: identifying as female; low socioeconomic status; and/or racial/ethnic minority (Black/African American; Hispanic/Latinx/Chicanx; Native American/Alaskan, and Native Hawaiian/Pacific Islander, or multi-racial). Common themes that emerged included the following: Challenges (Financial Factors, Role of Gender (i.e. identifying as female), and Race/Ethnicity Issues); Positive Influences (Role of Teacher, Role of Family); Other Interesting Insights (Wanting to be challenged in Computer Science Classes, Problems with the Marketing of Computer Science as a discipline). Social Identity Theory is used to better understand the experiences of high school students, especially what practices or beliefs keep underrepresented students of Computer Science from enrolling in Computer Science courses in the first place and/or persisting in the Computer Science field. Limitations of the current study are discussed as well as directions for future research and implications for a more culturally relevant pedagogical approach to teaching Computer Science and Computational Thinking in high schools. This project is funded by the National Science Foundation CS for All: Research and RPPs program, Award No. 2122367. 

This qualitative research project is part of a larger NSF-funded grant entitled "Cogenerative Development of Culturally Relevant Pedagogical Guidelines for Computer Science and Computational Thinking in High Schools." During Year 1 of the project, qualitative in-depth interviews were conducted with 26 high school students to better understand the challenges and barriers to enrollment in and engagement/success in Computer Science courses in high school. A grounded theory approach was used, given the exploratory nature of the study. Students were selected from three partner schools and had to meet at least one of the criteria associated with underrepresented students in Computer Science: identifying as female; low socioeconomic status; and/or racial/ethnic minority (Black/African American; Hispanic/Latinx/Chicanx; Native American/Alaskan, and Native Hawaiian/Pacific Islander, or multi-racial). Common themes that emerged included the following: Challenges (Financial Factors, Role of Gender (i.e. identifying as female), and Race/Ethnicity Issues); Positive Influences (Role of Teacher, Role of Family); Other Interesting Insights (Wanting to be challenged in Computer Science Classes, Problems with the Marketing of Computer Science as a discipline). Limitations of the current study are discussed as well as directions for future research and implications for a more culturally relevant pedagogical approach to teaching Computer Science and Computational Thinking in high schools. This project is funded by the National Science Foundation CS for All: Research and RPPs program, Award No. 2122367. 

Genital evolution can be driven by diverse selective pressures. Across taxa we see evidence of covariation between males and females, as well as divergent genital morphologies between closely related species. Quantitative analyses of morphological changes in coevolving male and female genitalia have not yet been shown in vertebrates. This study uses 2D and 3D geometric morphometrics to quantitatively compare the complex shapes of vaginal pouches and hemipenes across three species of watersnakes (the sister taxa Nerodia fasciata, N. sipedon, and a close relative N. rhombifer) to address the relationship between genital morphology and divergence time in a system where sexual conflict may have driven sexually antagonistic coevolution of genital traits. Our pairwise comparisons of shape differences across species show that the sister species have male and female genitalia that are significantly different from each other, but more similar to each other than to N. rhombifer. We also determine that the main axes of shape variation are the same for males and females, with changes that relate to deeper bilobation of the vaginal pouch and hemipenes. In males, the protrusion of the region of spines at the base of the hemipene trades off with the degree of bilobation, suggesting amelioration of sexual conflict, perhaps driven by changes in the relative size of the entrance of the vaginal pouch that could have made spines less effective.

 

A defining feature of cellular growth is that protein and mRNA amounts scale with cell size so that concentrations remain approximately constant, thereby ensuring similar reaction rates and efficient biosynthesis. A key component of this biosynthetic scaling is the scaling of mRNA amounts with cell size, which occurs even among cells with the same DNA template copy number. Here, we identify RNA polymerase II as a major limiting factor increasing transcription with cell size. Other components of the transcriptional machinery are only minimally limiting and the chromatin environment is largely invariant with size. However, RNA polymerase II activity does not increase in direct proportion to cell size, inconsistent with previously proposed DNA-titration models. Instead, our data support a dynamic equilibrium model where the rate of polymerase loading is proportional to the unengaged nucleoplasmic polymerase concentration. This sublinear transcriptional increase is then balanced by a compensatory increase in mRNA stability as cells get larger. Taken together, our results show how limiting RNA polymerase II and feedback on mRNA stability work in concert to ensure the precise scaling of mRNA amounts across the physiological cell size range. 

Hyatt, L, Greenwood, J., Butler, J., Magleby, S.P., Howell, L.L., “Using Cyclic Quadrilaterals to Design Cylindrical Developable Mechanisms,” Proceedings of the 2020 USCToMM Symposium on Mechanical Systems and Robotics, Mechanisms and Machine Science, vol 83, Springer, pp. 149-159, 2020.