Flexible learning removes barriers relating to time, place, and pace. While time management skills have been identified as necessary for learners to take advantage of flexible learning, relatively little is known about the temporal dimensions of flexible learning and how gender might relate to temporal flexibility and its perceived benefits. To address this gap, we analyzed data from 380,000 students participating in two massive open online courses to create a model that predicts course completion likelihood from learner time management behaviors and gender. Results supported most a priori assumptions. Successful course completers logged in frequently, devoted longer amounts of time to each session, moved quickly through course materials, and completed coursework early. However, consistent study was associated with lower course completion likelihood, and women benefited more from reduced consistency. These findings suggest that temporal flexibility may especially benefit women.

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Novel engineering materials and structures are increasingly designed for use in severe environments involving extreme transient variations in temperature and loading rates, chemically reactive flows, and other conditions. The Texas A&M University Hypervelocity Impact Laboratory (HVIL) enables unique ultrahigh-rate materials characterization, testing, and modeling capabilities by tightly integrating expertise in high-rate materials behavior, computational and polymer chemistry, and multi-physics multiscale numerical algorithm development, validation, and implementation. The HVIL provides a high-throughput test bed for development and tailoring of novel materials and structures to mitigate hypervelocity impacts (HVIs). A conventional, 12.7 mm, smooth bore, two-stage light gas gun (2SLGG) is being used as the aeroballistic range launcher to accelerate single and simultaneously launched projectiles to velocities in the range 1.5–7.0 km/s. The aeroballistic range is combined with conventional and innovative experimental, diagnostic, and modeling capabilities to create a unique HVI and hypersonic test bed. Ultrahigh-speed imaging (10M fps), ultrahigh-speed schlieren imaging, multi-angle imaging, digital particle tracking, flash x-ray radiography, nondestructive/destructive inspection, optical and scanning electron microscopy, and other techniques are being used to characterize HVIs and study interactions between hypersonic projectiles and suspended aerosolized particles. Additionally, an overview of 65 2SLGG facilities operational worldwide since 1990 is provided, which is the most comprehensive survey published to date. The HVIL aims to ( i) couple recent theoretical developments in shock physics with advances in numerical methods to perform HVI risk assessments of materials and structures, ( ii) characterize environmental effects (water, ice, dust, etc.) on hypersonic vehicles, and ( iii) address key high-rate materials and hypersonics research problems.

Similar to many chiropteran species, pregnant and lactating evening bats Nycticeius humeralis form maternity colonies to bear and raise their pups. Although evening bat maternity roosts have been studied in other locations, knowledge gaps exist regarding maternity roost site selection on the Gulf Coast of Texas, United States; thus, our objective was to quantify maternity roost characteristics of evening bats in this region. We radiotracked 11 female and subadult evening bats to nine roosts during June and July 2018 and 2019 captured in San Bernard Wildlife Refuge (SBNWR). No transmittered bats roosted in SBNWR and instead all roosts were located 3.6–4.5 km from the same capture site, within an 81-ha residential area of a 5,496-ha city. Five of the nine roosts were in tall, live, live oak trees Quercus virginana and one roost was in a residential home. Colony size of bats occupying the roosts ranged from 16 to 500+ bats. All evening bats, including those on properties we were denied access to, stayed in roosts for the full life of the transmitter (five–21 days) and no roost switching occurred. Although evening bats used SBNWR, potentially for foraging, results suggest trees in the residential area provided suitable maternity roost characteristics. A lack of roost switching may suggest a lack of available roost trees in SBNWR and residential areas or the selected roost trees were high quality. We recommend future studies increase sample sizes of evening bat roosts on the Gulf Coast of Texas, as well as assessing roost site selection of evening bats and monitoring bachelor colony and evening bat winter roost ecology.