Effect of time of day on perceived exertion at work rates above and below the ventilatory threshold

The effect of time of day on ratings of perceived exertion (RPE) at various intensities of cycling exercise, both below and above the ventilatory threshold, was studied in 32 subjects, 18 to 35 years of age. The ventilatory threshold occurred at the same (p greater than .05) mean (+/- SD) work rate in the morning (110.6 +/- 27.0 watts) and in the afternoon (111.9 +/- 23.9 watts) and was perceived as equally strenuous (p greater than .05) in the morning (RPE = 13.8 +/- 2.4) and in the afternoon (RPE = 13.6 +/- 2.8). At intensities below the ventilatory threshold, RPE was the same (p greater than .05) in the morning and in the afternoon; above the ventilatory threshold, RPE was lower (p less than .05) in the morning. We conclude that, during incremental submaximal cycling exercise above the ventilatory threshold, a particular work rate is perceived as less strenuous in the morning than in the afternoon. About 20% of this difference in RPE is explained by lower ventilatory demands in the morning.     

A Criterion-Referenced Approach to Student Ratings of Instruction

We developed a criterion-referenced student rating of instruction (SRI) to facilitate formative assessment of teaching. It involves four dimensions of teaching quality that are grounded in current instructional design principles: Organization and structure, Assessment and feedback, Personal interactions, and Academic rigor. Using item response theory and Wright mapping methods, we describe teaching characteristics at various points along the latent continuum for each scale. These maps enable criterion-referenced score interpretation by making an explicit connection between test performance and the theoretical framework. We explain the way our Wright maps can be used to enhance an instructor’s ability to interpret scores and identify ways to refine teaching. Although our work is aimed at improving score interpretation, a criterion-referenced test is not immune to factors that may bias test scores. The literature on SRIs is filled with research on factors unrelated to teaching that may bias scores. Therefore, we also used multilevel models to evaluate the extent to which student and course characteristic may affect scores and compromise score interpretation. Results indicated that student anger and the interaction between student gender and instructor gender are significant effects that account for a small amount of variance in SRI scores. All things considered, our criterion-referenced approach to SRIs is a viable way to describe teaching quality and help instructors refine pedagogy and facilitate course development.     

Sanitizing the Struggle: Barack Obama,Selma, and Civil Rights Memory

In this article, I examine Barack Obama’s use of collective memory during his 2007 campaign speech in Selma, Alabama. Specifically, I argue that Obama appeals to collective memory to challenge the Black community’s relationship to the past. He reframed the memory of the Civil Rights Movement in a manner favorable to his political aspirations. While this frame was politically expedient, it weakened Black political agency. It robbed the Black community of crucial rhetorical resources used to challenge structural inequalities in society. This article offers insight into the complex relationship between metaphor and collective memory. Specifically, I interrogate the role of metaphor as a crucial site where public memory is formed, disrupted, and rearticulated. Furthermore, I consider the implications of his use of memory for the future of the Black freedom struggle.     

Learning to play: A review and theoretical investigation of the developmental mechanisms and functions of cetacean play

Play is a behavioral phenomenon most commonly observed in the young of both solitary and social species. Documentation of play in cetaceans varies across species and settings. Cetacean play behavioral repertoires include a broad range of actions, such as the manipulation of diverse objects, blowing bubbles, chasing conspecifics, and swimming in spirals through the water. As is common in research on animal play, cetacean play has been grouped into categories by its form, including locomotor play, object play, and different variations of social play, such as affiliative games, play fighting, and socio-sexual play. Research has primarily focused on recording the topography of cetacean play and the demographics of the individuals engaging in play. However, these classifications are insufficient to address the possible developmental and societal functions of cetacean play behaviors, or the mechanisms with which play behaviors are spread between conspecifics and acquired by young members of cetacean populations. This article applies several developmental and social learning theories in order to organize current knowledge and guide future research.     

The Impact of a Professional Development Program on Teachers' Mathematical Knowledge for Teaching,Instruction, and Student Achievement

In this paper, we describe findings from a three-year evaluation of a well-developed mathematics professional development program that is commercially available on a wide scale. The professional development is designed to improve teachers' mathematical knowledge for teaching and to enable them to elicit more student thinking and reasoning during mathematics lessons. Specifically, it focused on helping teachers (a) learn more mathematics, (b) understand how children learn math, (c) use formative assessment to develop insight into what specific students know and do not know, and (d) develop effective classroom instructional strategies that enable student problem solving. Participants included 105 fourth- and fifth-grade teachers teaching in 19 low-income schools within a single district. Teachers were randomly assigned within schools either to a “business as usual” control group or to receive the professional development. The training consisted of a week-long summer institute and four to six in-service days during the school year. The training was run by full-time trained associates. We find some limited evidence of positive impacts on teachers' mathematical knowledge for teaching, but no effects on instructional practice or student outcomes.     

Advancing Diversity in STEM

Although progress has been made, greater efforts are needed to promote faculty diversity at the college and university levels, especially in STEM fields. Thus, it is important to elucidate best practices both for increasing awareness of diversity issues pertaining to higher education and for implementing change. This article focuses on the outcomes of a diversity workshop for college and university faculty hosted by the West Virginia Higher Education Policy Commission, Division of Science and Research. More specifically, it elucidates how participation in the workshop translated into practice at the faculty participants’ home institutions.     

Impaired acuity of the approximate number system underlies mathematical learning disability (dyscalculia)

Many children have significant mathematical learning disabilities (MLD, or dyscalculia) despite adequate schooling. The current study hypothesizes that MLD partly results from a deficiency in the Approximate Number System (ANS) that supports nonverbal numerical representations across species and throughout development. In this study of 71 ninth graders, it is shown that students with MLD have significantly poorer ANS precision than students in all other mathematics achievement groups (low, typically, and high achieving), as measured by psychophysical assessments of ANS acuity (w) and of the mappings between ANS representations and number words (cv). This relation persists even when controlling for domain-general abilities. Furthermore, this ANS precision does not differentiate low-achieving from typically achieving students, suggesting an ANS deficit that is specific to MLD.