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This paper explores the integration of computer science (CS) and computational thinking (CT) into middle and high school math classes by teachers who received pre-service CS training. Focusing on three participants within a larger study, the paper describes what they find relevant from their programs, how they apply CS/CT concepts and practices into their math instruction, and what role their value of CS/CT plays in their pedagogical approaches. Data were collected through two interviews and analyzed to present case studies. Findings describe how teachers’ integration of CS/CT varies from algorithmic thinking to prioritizing the process over the solution. Findings show the teachers’ motivation to bring CS to their students, whether by incorporating CS/CT practices in their math classroom or advocating for stand-alone classes. Recommendations for pre-service CS/CT-focused teacher preparation programs include greater emphasis on integration, culturally responsive teaching practices, and learning how to teach in addition to what to teach. 

We present the first volume-limited sample of spectroscopically confirmed hot subluminous stars out to 500 pc, defined using the accurate parallax measurements from theGaiaspace mission data release 3 (DR3). The sample comprises a total of 397 members, with 305 (~77%) identified as hot subdwarf stars, including 83 newly discovered systems. Of these, we observe that 178 (~58%) are hydrogen-rich sdBs, 65 are sdOBs (~21%), 32 are sdOs (~11%), and 30 are He-sdO/Bs (~10%). Among them, 48 (~16%) exhibit an infrared excess in their spectral energy distribution fits, suggesting a composite binary system. The hot subdwarf population is estimated to be 90% complete, assuming that most missing systems are these composite binaries located within the main sequence (MS) in theGaiacolour-magnitude diagram. The remaining sources in the sample include cataclysmic variables, blue horizontal branch stars, hot white dwarfs, and MS stars. We derived the mid-plane densityρ₀and scale height h_zfor the non-composite hot subdwarf star population using a hyperbolic sechant profile (sech²). The best-fit values areρ₀= 5.17 ± 0.33 × 10⁻⁷stars pc⁻³and h_z= 281 ± 62 pc. When accounting for the composite-colour hot subdwarfs and their estimated completeness, the mid-plane density increases toρ₀= 6.15_−0.53^+1.16× 10⁻⁷stars pc⁻³. This corrected space density is an order of magnitude lower than predicted by population synthesis studies, supporting previous observational estimates. 

ABSTRACT Plants require water and nutrients for survival, although the effects of their availabilities on plant fitness differ amongst species. Genome size variation, within and across species, is suspected to influence plant water and nutrient requirements, but little is known about how variations in these resources concurrently affect plant fitness based on genome size. We examined how genome size variation between autopolyploid cytotypes influences plant morphological and physiological traits, and whether cytotype‐specific trait responses differ based on water and/or nutrient availability.Diploid and autotetraploidSolidago gigantea(Giant Goldenrod) were grown in a greenhouse under four soil water:N+P treatments (L:L, L:H, H:L, H:H), and stomata characteristics (size, density), growth (above‐ and belowground biomass, R/S), and physiological (A_net,E,WUE) responses were measured.Resource availabilities and cytotype identity influenced some plant responses but their effects were independent of each other. Plants grown in high‐water and nutrient treatments were larger, plants grown in low‐water or high‐nutrient treatments had higherWUEbut lowerE, andA_netandErates decreased as plants aged. Autotetraploids also had larger and fewer stomata, higher biomass and largerA_netthan diploids.Nutrient and water availability could influence intra‐ and interspecific competitive outcomes. AlthoughS. giganteacytotypes were not differentially affected by resource treatments, genome size may influence cytogeographic range patterning and population establishment likelihood. For instance, the larger size of autotetraploidS. giganteamight render them more competitive for resources and niche space than diploids. 

This poster describes how we are using research to inform the development of a cybersecurity education pathway to attract and retain students from groups that are underrepresented in computing fields. The partners include a non-profit research organization, a community-based tech workforce center, a community college, and a K-12 school district that serves predominantly Latinx students. The poster describes our goals, activities, the data we have collected, and how they are being used to create a sustainable pathway from high school to college that attracts a diversity of students. We describe our stages of research utilization, as well as the challenges that we are facing related to using research to ensure equity in the cybersecurity education pathway. 

Context. The TESS satellite was launched in 2018 to perform high-precision photometry from space over almost the whole sky in a search for exoplanets orbiting bright stars. This instrument has opened new opportunities to study variable hot subdwarfs, white dwarfs, and related compact objects. Targets of interest include white dwarf and hot subdwarf pulsators, both carrying high potential for asteroseismology. Aims. We present the discovery and detailed asteroseismic analysis of a new g -mode hot B subdwarf (sdB) pulsator, EC 21494−7018 (TIC 278659026), monitored in TESS first sector using 120-s cadence. Methods. The TESS light curve was analyzed with standard prewhitening techniques, followed by forward modeling using our latest generation of sdB models developed for asteroseismic investigations. By simultaneously best-matching all the observed frequencies with those computed from models, we identified the pulsation modes detected and, more importantly, we determined the global parameters and structural configuration of the star. Results. The light curve analysis reveals that EC 21494−7018 is a sdB pulsator counting up to 20 frequencies associated with independent g -modes. The seismic analysis singles out an optimal model solution in full agreement with independent measurements provided by spectroscopy (atmospheric parameters derived from model atmospheres) and astrometry (distance evaluated from Gaia DR2 trigonometric parallax). Several key parameters of the star are derived. Its mass (0.391 ± 0.009  M ⊙ ) is significantly lower than the typical mass of sdB stars and suggests that its progenitor has not undergone the He-core flash; therefore this progenitor could originate from a massive (≳2  M ⊙ ) red giant, which is an alternative channel for the formation of sdBs. Other derived parameters include the H-rich envelope mass (0.0037 ± 0.0010  M ⊙ ), radius (0.1694 ± 0.0081  R ⊙ ), and luminosity (8.2 ± 1.1  L ⊙ ). The optimal model fit has a double-layered He+H composition profile, which we interpret as an incomplete but ongoing process of gravitational settling of helium at the bottom of a thick H-rich envelope. Moreover, the derived properties of the core indicate that EC 21494−7018 has burnt ∼43% (in mass) of its central helium and possesses a relatively large mixed core ( M core  = 0.198 ± 0.010  M ⊙ ), in line with trends already uncovered from other g-mode sdB pulsators analyzed with asteroseismology. Finally, we obtain for the first time an estimate of the amount of oxygen (in mass; X (O) core = 0.16 +0.13 −0.05 ) produced at this stage of evolution by an helium-burning core. This result, along with the core-size estimate, is an interesting constraint that may help to narrow down the still uncertain 12 C( α ,  γ ) 16 O nuclear reaction rate.