The Initial State of Students Taking an Introductory Physics MOOC

As part of a larger research project into massively open online courses (MOOCs), we have investigated student background, as well as student participation in a physics MOOC with a laboratory component. Students completed a demographic survey and the Force and Motion Conceptual Evaluation at the beginning of the course. While the course is still actively running, we have tracked student participation over the first five weeks of the eleven-week course.Comment: Accepted to PERC Proceedings 201

Peer Evaluation of Video Lab Reports in a Blended Introductory Physics Course

The Georgia Tech blended introductory calculus-based mechanics course emphasizes scientific communication as one of its learning goals, and to that end, we gave our students a series of four peer-evaluation assignments intended to develop their abilities to present and evaluate scientific arguments. Within these assignments, we also assessed students' evaluation abilities by comparing their evaluations to a set of expert evaluations. We summarize our development efforts and describe the changes we observed in student evaluation behavior.Comment: 4 pages, 1 table, 2 figures, submitted to Summer 2014 PERC Proceeding

Understanding Student Computational Thinking with Computational Modeling

Recently, the National Research Council's framework for next generation science standards highlighted "computational thinking" as one of its "fundamental practices". 9th Grade students taking a physics course that employed the Modeling Instruction curriculum were taught to construct computational models of physical systems. Student computational thinking was assessed using a proctored programming assignment, written essay, and a series of think-aloud interviews, where the students produced and discussed a computational model of a baseball in motion via a high-level programming environment (VPython). Roughly a third of the students in the study were successful in completing the programming assignment. Student success on this assessment was tied to how students synthesized their knowledge of physics and computation. On the essay and interview assessments, students displayed unique views of the relationship between force and motion; those who spoke of this relationship in causal (rather than observational) terms tended to have more success in the programming exercise.Comment: preprint to submit to PERC proceedings 201

Sources of Error for Ultrasonic Measurements of Steer Compositional Traits in Grazing Studies

Real-time ultrasound technology has potential use for measuring compositional traits in grazing studies. Sources of error with this application must be identified for designing experiments with adequate precision to determine treatment effects. A study was conducted to evaluate breed type (Angus x Brahman, AB; Simmental x [Angus x Brahman], SAB; Simmental x [Brahman x Hereford], SBH), initial body weight, and initial ultrasonic measures as sources of experimental error in the analyses of external fat (EF) depths and longissimus dorsi (ribeye) areas (LDA). Steers were ultrasonically scanned at the initiation and conclusion of a grazing study that examined stocking rate effects on average daily gain (ADG) and body condition of steers grazing a mixture of rye (Secale cereale L.) and ryegrass (Lolium multiflorum L.). Breed type did not affect (P \u3e 0.10) final or increases in EF, and curvilinear trends of increased EF with increasing ADG (P \u3e 0.10) among the breed types over the range of ADG (0.03 kg d-1 to 1.62 kg d-1). The three breed types showed curvilinear increases in LDA as ADG increased, but the trends were different (P \u3c 0.05) for SBH than for the other two types. Final LDA and magnitude of increases in EF and LDA over the experimental period were influenced (P \u3c 0.05) by initial body weight. Results indicated that allotting cattle to pastures based on a combination of breed type and body weight should improve precision in detecting treatment effects

Forage Crop Water Use and Production Under Dryland Conditions

Forage crops contribute diversity and buffer agronomic risk in water-limited cropping systems. Knowledge of growth responses to uncertain water supply can help guide crop selection and management—including timing of harvest. Our research objective was to determine water use and growth responses of forage winter triticale and forage sorghum under rainfed conditions

Recovery of Yearling Calves from Fescue Toxicosis

Tall fescue (Lolium arundinaceum (Schreb.) S.J. Darbyshire) is widely utilized for grazing in the transition zone between the temperate and subtropical regions of the eastern U.S.A. Cattle grazing tall fescue frequently exhibit fescue toxicosis, a malady caused by consumption of toxins produced by the endophyte, Neotyphodium coenophialum. Symptoms of fescue toxicosis include retention of rough hair coat, increased body temperature and laboured respiration. Heat stress may be severe at onset of high ambient temperature and humidity. Transporting cattle exhibiting toxicosis can therefore be difficult because combined stresses of the toxicosis and transporting often result in high mortality. An experiment was conducted to measure trends in rectal temperatures for yearling steers following removal from tall fescue and placement on a fescue-free diet

Ultrasonic Measures of Backfat Depth and Ribeye Area for Steers Grazing Rye-Ryegrass at Three Stocking Rates

Last updated: 6/12/200

Keeping the voice fit in the group fitness industry: a qualitative study to determine what instructors want in a voice education program

This study aimed to provide a descriptive summary of (1) group fitness instructors' (GFIs') experiences of occupational voice use and education, and (2) the content and mode of delivery desired by GFIs in an education and training program.This is a qualitative inductive approach using a semi-structured interview.Semi-structured interviews were conducted with eight GFIs recruited via self-selection sampling. Participants were asked to comment on their experiences of voice use, voice education, and their preferences for future education and training.Participants reported experiencing occupational voice difficulties, and cited inadequate voice education, faulty equipment, and apathetic fitness industry attitudes as core barriers to vocal health. Content focusing on vocal hygiene, safe occupational voice use, use of amplification equipment, and addressing industry attitudes to voice was desired by participants. A combination of face-to-face, web-based, and app-based delivery options was suggested.The data from this study should be considered when designing a vocal education and training package tailored to the needs of GFIs and the fitness industry