Reliability and validity of the Zebris FDM-THQ instrumented treadmill during running trials

Little is known about the reliability, validity and smallest detectable differences of selected kinetic and temporal variables recorded by the Zebris FDM-THQ instrumented treadmill especially during running. Twenty male participants (age = 31.9 years (±5.6), height = 1.81 m (±0.08), mass = 80.2 kg (±9.5), body mass index = 24.53 kg/m² (±2.53)) walked (5 km/h) and ran (10 and 15 km/h) on an instrumented treadmill, wearing running shoes fitted with Pedar-X insoles. A test-double retest protocol was conducted over two consecutive days. Maximal vertical force (F_max), contact time (CT) and flight time (FT) data from 10 consecutive steps were collected. Within- and between-day reliability, smallest detectable differences (SDD) and validity (95% limits of agreement (LOA)) were calculated. ICC values for the Zebris for Fmax were acceptable (ICC ≥ 0.7) while CT and FT reliability indices were predominantly good (ICC ≥ 0.8) to excellent (ICC ≥ 0.9). The Zebris significantly underestimated Fmax when compared with the Pedar-X. The 95% LOA increased with speed. SDD ranged between 96 N and 169 N for Fmax, 0.017s and 0.055s for CT and 0.021s and 0.026s for FT. In conclusion, Zebris reliability was acceptable to excellent for the variables examined, but inferior in comparison with Pedar-X. With increased running speeds, a bias effect (underestimation) existed for the Zebris compared with Pedar-X.     

Impairment of teacher efficiency during extended sessions of test correction

SUMMARY The relationship between monotonous work, mental fatigue, and reduction in efficiency has been discussed at length in the literature. This paper examines a theory, based on the interactions revealed in those studies, that uninterrupted examination of a large number of tests over an extended period of time, leads to inconsistency in grading. Three specialists judged typed compositions of seventh-grade pupils, and independently awarded the grade of 80% to 31 papers. These compositions were submitted to 60 female teachers. Each teacher received all 31 papers, stacked in one of three different, randomly arranged sequences. The subjects, unaware of the earlier review, were asked to read the compositions in one sitting and in the order in which they were stacked, and to assign a grade. There was no communication between teachers in the project with regard to the task. The variable found to contribute significantly to the grading pattern was the order in which the essays were arranged. The first tests received lower grades, on average, than those awarded by the specialists. As the teachers worked their way through the stack, the grades gradually rose, and eventually exceeded those given by the specialists. The discrepancy between the mean evaluation of the first papers and last papers in the pile was approximately 10%. Teacher seniority and other variables tested did not contribute significantly to the process.     

Paradise Restored: The significance of coincidence in some children's books

Pat Pinsent is a Principal Lecturer in English at the Roehampton Institute, London, where she teaches children's literature to undergraduates as well as courses on language and literacy for in-service teachers.     

Learning to Teach Science: The Curriculum of Student Teaching in Hiroshima "Attached" Schools

Journal of Science Teacher Education -     

Microfluidic electromanipulation with capacitive detection for the mechanical analysis of cells

The mechanical behavior of cells offers insight into many aspects of their properties. We propose an approach to the mechanical analysis of cells that uses a combination of electromanipulation for stimulus and capacitance for sensing. To demonstrate this approach, polystyrene spheres and yeast cells flowing in a 25 μm×100 μm microfluidic channel were detected by a perpendicular pair of gold thin film electrodes in the channel, spaced 25 μm apart. The presence of cells was detected by capacitance changes between the gold electrodes. The capacitance sensor was a resonant coaxial radio frequency cavity (2.3 GHz) coupled to the electrodes. The presence of yeast cells (Saccharomyces cerevisiae) and polystyrene spheres resulted in capacitance changes of approximately 10 and 100 attoFarad (aF), respectively, with an achieved capacitance resolution of less than 2 aF in a 30 Hz bandwidth. The resolution is better than previously reported in the literature, and the capacitance changes are in agreement with values estimated by finite element simulations. Yeast cells were trapped using dielectrophoretic forces by applying a 3 V signal at 1 MHz between the electrodes. After trapping, the cells were displaced using amplitude and frequency modulated voltages to produce modulated dielectrophoretic forces. Repetitive displacement and relaxation of these cells was observed using both capacitance and video microscopy.     

Teaching motivations,characteristics and professional growth: results from the Great Expectations (GE) programme in the United States

This present study sought to explore reasons given by K-12 teachers about their motivation to remain in teaching, their motivation for engaging in professional development, and characteristics of their teaching. Participants (N = 151) were public teachers of different grade levels from the USA enrolled in a one-week professional development training. Respondents’ ratings on reasons for continuing teaching revealed that four key-specific factors were the main influences for continuing to teach, namely intrinsic reasons, extrinsic reasons, job perception, and extended reasons. Further analysis indicated that their reasons for teaching were correlated with specific incentives for attending the professional development training, with teachers’ instructional beliefs, and with professional development programme outcomes. Study results are discussed in relationship with teaching motivation and implications for teachers’ professional growth.     

Gender Gaps in Achievement and Participation in Multiple Introductory Biology Classrooms

Although gender gaps have been a major concern in male-dominated science, technology, engineering, and mathematics disciplines such as physics and engineering, the numerical dominance of female students in biology has supported the assumption that gender disparities do not exist at the undergraduate level in life sciences. Using data from 23 large introductory biology classes for majors, we examine two measures of gender disparity in biology: academic achievement and participation in whole-class discussions. We found that females consistently underperform on exams compared with males with similar overall college grade point averages. In addition, although females on average represent 60% of the students in these courses, their voices make up less than 40% of those heard responding to instructor-posed questions to the class, one of the most common ways of engaging students in large lectures. Based on these data, we propose that, despite numerical dominance of females, gender disparities remain an issue in introductory biology classrooms. For student retention and achievement in biology to be truly merit based, we need to develop strategies to equalize the opportunities for students of different genders to practice the skills they need to excel.