skip to main content

Search for: All records

Creators/Authors contains: "Brown, Jonathan"

Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher. Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?

Some links on this page may take you to non-federal websites. Their policies may differ from this site.

  1. With large enrollments (about 200-350) of primarily non-majors, engaging students in the required introductory materials science and engineering course at our university has been a longstanding challenge. In moving to the virtual format in the fall of 2020, we significantly adapted several aspects of the course, many of which have continued to the hybrid format in future semesters, with good results. The primary content was provided through asynchronous videos; this format allowed us to break content into digestible pieces. In particular, multiple mini-lectures and example videos were pre-recorded for each week, with a total viewing time per week somewhat less than the typical total class time. To provide real-time, structured interaction, one live virtual class session per week was held, centered on previously submitted student questions. Smaller teaching-assistant-led recitation sections also met live (virtually or in person), during which “clicker” questions were asked through TopHat. Assignments were also updated to take advantage of the virtual format. Multiple small assignments with lower stakes were due throughout the week: a reading/lecture quiz, a survey to submit questions, and a shortened homework assignment. Finally, we changed some content near the end of the course to allow students to connect the course to theirmore »own career aspirations, which we expect can aid in longterm retention. Specifically, students chose among several possible topics to cover in the final weeks, covered via typical pre-recorded lectures and reading, and also guest lectures. They wrote an abstract-length reflection on how they could use what they learned in this course later in their careers. Overall, students remained engaged with the course throughout the semester and provided favorable comments and evaluations of the course, including higher numerical evaluations of the course than in prior semesters.« less
  2. Abstract

    Organisms may internally or behaviorally regulate their body temperatures or conform to the ambient air temperatures. Previous evidence is mixed on whether wing pigmentation influences thermoregulation in various odonates.

    We investigated the thermal response of sympatric North AmericanCalopteryx aequabilisandCalopteryx maculatawith a thermal imaging study across a 25°C ambient temperature range.

    We found that regressions of thorax temperature on ambient temperature standardized by species had similar slopes for male and femaleC. maculata, but females were consistently 1.5°C warmer than males. In contrast, the sexes ofC. aequabilisdiffered in slope, withC. aequabilisfemales having a slope less than 1.0 and males having a slope greater than 1.0.

    We found that regressions of thorax temperature on ambient temperature standardized by sex had similar slopes for males and females of both species, butC. maculatafemales were consistently 2.1°C warmer thanC. aequabilisfemales.

    Given thatC. aequabilisis strongly sexually dimorphic in pigment, butC. maculatais not, our findings suggest that wing pigmentation may influence thermal response rate in sympatric populations of both species.