Scientist Spotlights in Secondary Schools: Student Shifts in Multiple Measures Related to Science Identity after Receiving Written Assignments.

Based on theoretical frameworks of scientist stereotypes, possible selves, and science identity, written assignments were developed to teach science content through biographies and research of counter-stereotypical scientists-Scientist Spotlights (www.scientistspotlights.org). Previous studies on Scientist Spotlight assignments showed significant shifts in how college-level biology students relate to and describe scientists and in their performance in biology courses. However, the outcomes of Scientist Spotlight assignments in secondary schools were yet to be explored. In collaboration with 18 science teachers from 12 schools, this study assessed the impacts of Scientist Spotlight assignments for secondary school students. We used published assessment tools: Relatability prompt; Stereotypes prompt; and Performance/Competence, Interest, and Recognition (PCIR) instrument. Statistical analyses compared students' responses before and after receiving at least three Scientist Spotlight assignments. We observed significant shifts in students' relatability to and descriptions of scientists as well as other science identity measures. Importantly, disaggregating classes by implementation strategies revealed that students' relatability shifts were significant for teachers reporting in-class discussions and not significant for teachers reporting no discussions. Our findings raise questions about contextual and pedagogical influences shaping student outcomes with Scientist Spotlight assignments, like how noncontent Instructor Talk might foster student shifts in aspects of science identity.

Investigating Instructor Talk among Graduate Teaching Assistants in Undergraduate Biology Laboratory Classrooms.

Instructor Talk-noncontent and nonlogistical language that is focused on shaping the classroom learning environment-is a recently defined variable that may play an important role in how undergraduates experience courses. Previous research characterized Instructor Talk used by faculty teaching in biology lecture classrooms. However, graduate teaching assistants (GTAs) and laboratory classrooms represent critical factors in undergraduate education, and Instructor Talk in this context has yet to be explored. Here, we present findings analyzing Instructor Talk used by GTAs teaching in undergraduate biology laboratory classrooms. We characterized the Instructor Talk used by 22 GTA instructors across 24 undergraduate biology laboratory courses in the context of a single, urban, Hispanic-serving and Asian American and Pacific Islander-serving Institution. We found that Instructor Talk was present in every course studied, GTAs with pedagogical training and prior teaching experience used more Instructor Talk than those without, and GTAs teaching laboratory courses used more Instructor Talk than previous observations of faculty teaching lecture courses. Given the widespread use of Instructor Talk and its varying use across contexts, we predict that Instructor Talk may be a critical variable in teaching, specifically in promoting equity and inclusion, which merits continued study in undergraduate science education.

Investigating Student Perceptions of Instructor Talk: Alignment with Researchers' Categorizations and Analysis of Remembered Language.

Instructor Talk-the noncontent language used by an instructor during class time-is likely to influence learning environments in science classrooms from the student perspective. Despite Instructor Talk being found in every science course thus far, investigations into student perceptions and memories of it are limited. We investigated to what extent undergraduate biology students 1) were aligned with researchers in their perceptions of Instructor Talk as Positively Phrased or Negatively Phrased and 2) remembered Instructor Talk. To test these ideas, we engaged 90 biology students in a multipart assessment. First, students were given randomly selected Instructor Talk quotes, half Positively Phrased and half Negatively Phrased, and were asked to evaluate each quote as promoting a positive or negative learning environment. Overall, students evaluated the Instructor Talk quotes similarly to researchers' categorizations (p < 0.0001). Second, students were asked to provide examples of remembered instructor language from their biology courses that they felt promoted a positive or negative learning environment. Most students shared multiple memories, and ∼75% of these memories could be coded with the Instructor Talk frameworks. Given that students perceive and remember Instructor Talk as impacting the learning environment, Instructor Talk may be an explanatory variable for differential student outcomes across studies of active learning.

Melatonin Administration Methods for Research in Mammals and Birds.

Endocrine research in animals often entails exogenous hormone administration. Special issues arise when developing administration protocols for hormones with circadian and seasonal periodicity. This article reviews various methods for the exogenous administration of hormones with such periodicities by focusing on melatonin. We discuss that methodological variations across studies can affect experimental results. Melatonin administration techniques used in vertebrates includes infusion pumps, beeswax pellets, oral administration, injections, SILASTIC capsules, osmotic pumps, transdermal delivery, beads, and sponges.