Using micro-sensor data to quantify macro kinematics of classical cross-country skiing during on-snow training

Abstract

Micro-sensors were used to quantify macro kinematics of classical cross-country skiing techniques and measure cycle rates and cycle lengths during on-snow training. Data were collected from seven national level participants skiing at two submaximal intensities while wearing a micro-sensor unit (MinimaxX^?). Algorithms were developed identifying double poling (DP), diagonal striding (DS), kick-double poling (KDP), tucking (Tuck), and turning (Turn). Technique duration (T-time), cycle rates, and cycle counts were compared to video-derived data to assess system accuracy. There was good reliability between micro-sensor and video calculated cycle rates for DP, DS, and KDP, with small mean differences (Mdiff% = ?0.2 ± 3.2, ?1.5 ± 2.2 and ?1.4 ± 6.2) and trivial to small effect sizes (ES = 0.20, 0.30 and 0.13). Very strong correlations were observed for DP, DS, and KDP for T-time (r = 0.87–0.99) and cycle count (r = 0.87–0.99), while mean values were under-reported by the micro-sensor. Incorrect Turn detection was a major factor in technique cycle misclassification. Data presented highlight the potential of automated ski technique classification in cross-country skiing research. With further refinement, this approach will allow many applied questions associated with pacing, fatigue, technique selection and power output during training and competition to be answered.     

Students’ understanding of the number line / Estudiantes pensando en la recta numérica

We studied the conceptions of students coming from secondary education and university regarding the number line as a representation of real numbers. In the context of a wider questionnaire, 307 students were presented with a task consisting of two verbal items and one graphic item related to the number line. The students were all at different levels in their study of mathematics (in the third, fourth or fifth year of secondary education, or at the beginning or advanced stage of a university degree in mathematics, biology or physical education). A gradient in the depth of the students’ conceptions, associated with the level of their studies in mathematics, was found. This gradient extends from the estrangement of facing the problem or a conception of a drawn or physical matter line, which was associated with students with a lower level of mathematical studies, passing through a vision centred around potential numeric density or a line containing points (discrete), up to an instrumental conception of the line as supportive of magnitudes in advanced students of biology and focusing on continuity sustained by advanced students of mathematics.     

Restructuring a traditional student teacher supervision model: Fostering enhanced professional development and mentoring within a professional development school context

The purpose of this study was to pilot an alternative student teaching supervision model at a college of education in a US context. In the study, the collaborators used multiple paired dyads to supervise student teachers with multiple supports from college faculty. This study examined how teachers and university faculty planned the use of paired dyads and how participants responded to the innovation. The findings suggest teachers and junior faculty can undertake bottom-up reform within larger systemic constraints.     

The Effects of Structural Attributes and Demographic Characteristics on Protege Satisfaction in Mentoring Programs

This study examined whether the structural attributes of a formal mentoring program and/or certain demographic characteristics of participants in the program influence protege satisfaction. Proteges, employed in a traditionally male occupation, were sampled from a federal agency's mentoring program. According to policy, the agency attempted to assign proteges to one of three mentors they previously requested. An internally-developed measure, designed to assess protege satisfaction, was distributed after their completion in the program. A total of 565 surveys were received from 1998 to 2000. Results indicated that feedback in the assignment process and the frequency of meetings between the protege and mentor were more important determinants of protege satisfaction than racial and gender differences between proteges and the dyad.     

Lexical- and sentence-level processes in comprehension of written sentences

Two experiments and three measures of lexical skills (word finding, rapid automatized naming, receptive vocabulary) were administered to 24 third and 24 fifth graders. Each experiment included two between-subject variables (grade and sex) and four within-subject variables (mode of sentence presentation – one word and one-sentence-at-a-time; word type – orthographic, phonological and semantic foils; position of foil in sentence – beginning, middle, and end; and sentence type – meaningful and nonsense). The experiments contrasted on reading comprehension task: receptive sentence acceptability (Experiment 1) or expressive sentence reproduction (Experiment 2). One-word-at-a-time presentation, which highlights the lexical unit, resulted in better accuracy on the expressive task that required verbatim reproduction than on the forced choice receptive task. Word finding and rapid automatized naming that require active production of phonologically-referenced name codes, but not receptive vocabulary, were correlated with measures of word recognition and reading comprehension in the experiments and on the psychometric tests. These results are consistent with Perfetti's contention that a phonologically-based name code is the heart of lexical access.     

Green beans: Gardening with two's

The nearby neighborhood garden project provided an almost daily trip for our group of two-year-olds. There we discovered limitless opportunities for learning. Gardening provided a sense of continuity that is hard to achieve with young ones.Karen Hack is the Early Childhood Special Education Teacher of the two's group at the Infant Care Center. Virginia Flynn was the Administrative Supervisor of the Infant Care Center and is currently Assistant Education Director of the Infant Health and Development Program, The New York League for Early Learning, Inc.     

The incidence of severe physical child abuse in Wales

OBJECTIVES: The purposes of this study were: (1) to ascertain the incidence and nature of severe physical child abuse in Wales; (2) to ascertain the incidence of all physical abuse in babies under 1 year of age; and (3) to determine whether child protection registers (CPR) accurately reflect the numbers of children who are physically abused. METHODS: This is a population-based incidence study based in Wales, UK, for 2 years from April 1996 through March 1998. Children studied were under the age of 14 with severe physical abuse consistent with the criminal law level of Grievous Bodily Harm. This included seven categories of injury (death; head injury including subdural hemorrhage; internal abdominal injury; physical injury in Munchausen Syndrome by Proxy including suffocation; fracture; burn or scald; adult bite). Cases were ascertained by a pediatrician surveillance reporting system (WPSU). A criterion for inclusion was multidisciplinary agreement that physical abuse had occurred (at case conference, strategy meeting, or Part 8 Review). The incidence of all babies under 1 year of age with physical abuse was also studied. Ascertainment of babies under the age of 1 year was undertaken from CPR as well as the WPSU. RESULTS: Severe abuse is six times more common in babies [54/100,000/year (95% CI +/- 17.2)] than in children from 1 year to 4 years of age [9.2/100,000 (95% CI +/- 3.6)]. It is 120 times more common than in 5- to 13-year-olds [0.47/100,000 (95% CI +/- 0.47)]. This is mainly because two types of serious abuse (brain injury including subdural hemorrhage and fractures) are more common in babies under the age of 1 year than older children. Using data from two sources (the WPSU and CPRs), the incidence of physical abuse in babies is 114/100,000 (CI 114 +/- 11.8) per year. This equates to 1 baby in 880 being abused in the first year of life. The largely rural Health Authority area in Wales had incidence figures for abuse in babies that were 50% of the three other predominantly urban Health Authority areas. Boys throughout the series were more at risk of being severely abused than girls (p < .025). Only 29% of the babies under 1 year of age on the CPR had actually been injured. Thirty percent of abused babies under the age of 1 year and 73% of severely abused children over the age of 1 year had caused previous concern to health professionals regarding abuse or neglect. Conclusions: Physical abuse is a significant problem in babies under the age of 1 year. Very young babies (under 6 months old) have the highest risk of suffering damage or death as a result of physical abuse. Severe abuse, in particular subdural hematoma and fracture, is much more common in babies than in older children. There is evidence of failure of secondary prevention of child abuse by health professionals, with a greater need to act on concerns regarding abuse and neglect. Interagency child protection work in partnership with parents should focus more on protecting babies under age 1 year from further abuse than on maintenance of the infant within an abusive home. The CPR is not intended as an accurate measure of children suffering abuse. It is a record of children requiring a child protection plan and must not be used as a measure of numbers of abused children.     

Friendship formation in inclusive early childhood classrooms: what is the teacher’s role?

This study examined strategies teachers reported using to support friendships among young children in inclusive early childhood classrooms. The teachers included 25 general early childhood educators from 9 child care centers and 20 early childhood special educators from 9 specialized programs. The Playmates and Friends Questionnaire for Teachers documented the number and nature of children’s friendships and teachers’ reported use of 11 different strategies to support individual friendships. Overall, the friendship strategies that teachers reported using most frequently included providing sufficient free choice time, allowing children to form their own friendships, and commenting on the play between friends. The majority of teachers reported rarely using two strategies: arranging for children to play together outside of the classroom and allowing two friends to exclude other children from their play. Teachers reported using more active friendship strategies to support dyads in which one or both children had special needs. Implications of these findings to support friendship formation in inclusive early childhood settings and directions for future research are presented.     

‘I love a curry’: student-teacher discourse around ‘race’ and ethnicity at a UK university

This paper presents aspects of a small scale study that considered student teachers’ language and discourse around race and ethnicity at a university in the northwest of England. The first part of the paper critiques current education-related policy, context and practice to situate the research and then draws upon aspects of critical race theory and whiteness theory as frames of reference. In the research, 250 student-teachers completed questionnaires that invited responses to statements about race and ethnicity and this was followed by two semi-structured group interviews. A discourse analysis approach was taken to analyse the language used in the questionnaire responses and, in particular, the group interviews. Recurrent discursive configurations were characterised by language that signified othering, correct knowledge, personalisation and discomfort. Hesitations and silences during group discussions perhaps intimated thinking time and also maybe a reluctance to talk about aspects of race and ethnicity, and what was not said remains significant. It is suggested that a reconstruction of a teacher/educator subjectivity that fosters self-reflection on values and racial positioning, is needed in teacher education, alongside critical examination of the silences and discomfort surrounding race and ethnicity.