Effect of chainring ovality on joint power during cycling at different workloads and cadences     

Gerda Strutzenberger  Tobias Wunsch  Josef Kroell  Jacqueline Dastl  Hermann Schwameder 《Sports biomechanics / International Society of Biomechanics in Sports》2014,13(2):97-108

Non-circular chainrings theoretically enhance cycling performance by increasing effective chainring diameter and varying crank velocity, but research has failed to consistently reproduce the benefits in cycling trials. The aim of this study was (1) to investigate the effect of different chainring shapes on sagittal knee joint moment and sagittal lower limb joint powers and (2) to investigate whether alterations are affected by cadence and workload. Fourteen elite cyclists cycled in six conditions (70, 90 and 110 rpm, each at 180 and 300 W), for 2 min each, using three chainrings of different ovalities (1.0–1.215). Kinematic data and pedal forces were collected. For most conditions, only the chainring with the highest ovality (1.215) was characterised by smaller sagittal knee joint moments, smaller relative sagittal knee joint power contribution and larger relative sagittal hip joint power contribution, which suggests a change from maximising efficiency to maximising power production. Effect sizes increased with higher cadences, but not with higher workload. This study has application for athletes, clinicians and sports equipment industry as a non-circular chainring can change joint-specific power generation and decrease knee joint moment, but certain ovality seems to be necessary to provoke this effect.  相似文献   

Face-to-face contact in blended learning for intercultural education: the role of teachers     

Roger Austin  Angela Rickard  Jacqueline Reilly 《Irish Educational Studies》2017,36(3):323-340

In societies experiencing or emerging from conflict, teachers often deliver educational programmes designed to build community cohesion. We report on research which examined teachers’ views of the implementation of a programme involving both face-to-face and online contact between pupils. Findings suggest that this blended approach is highly motivational, enhancing online work and relationship building. The research underlines the importance of the political, educational and historical context for work of this sort and the impact this has on the particular blend of online and face-to-face interaction. Implications for policymakers and teachers include value for money and sustainability of blended intercultural education in similar contexts.  相似文献   

The influence of academic culture on quality management system ISO 9001 maintenance within Malaysian universities     

Siti Arni Basir  John Davies  Jacqueline Douglas  Alexander Douglas 《Journal of Higher Education Policy & Management》2017,39(3):320-340

This study investigates the influence of the elements of academic culture on quality management system ISO 9001 maintenance within Malaysian universities. There is a dearth of empirical studies on maintaining ISO 9001, particularly in the higher education context. From the literature review, academic culture was classified according to four elements – academic freedom, individualism, professionalism and collegiality. Two case studies were conducted within Malaysian universities that had been ISO 9001-certified for 5 years. At the time of this research, these two were the only universities that had certification for their entire organisation. (Most organisations gain certification for specific departments). The findings showed that academic freedom, individualism and collegiality had worked against ISO 9001 maintenance, while professionalism had influenced ISO 9001 maintenance both positively and negatively. The opposites of individualism (teamwork) and collegiality (managerialism) had supported ISO 9001 maintenance in one of the cases.  相似文献   

Early contribution of phonological awareness and later influence of phonological memory throughout reading acquisition     

Christelle Nithart  Elisabeth Demont  Marie‐Noëlle Metz‐Lutz  Steve Majerus  Martine Poncelet  Jacqueline Leybaert 《Journal of Research in Reading》2011,34(3):346-363

The acquisition of reading skills is known to rely on early phonological abilities, but only a few studies have investigated the independent contribution of the different steps involved in phonological processing. This 1‐year longitudinal study, spanning the initial year of reading instruction, aimed at specifying the development of phonological discrimination, awareness and various aspects of phonological memory and at assessing their respective contributions to early reading acquisition. Our results show an increase in performance at each phonological processing step, but also suggest a qualitative evolution in their relative importance. Hierarchical regression analyses indicate that reading skills are mainly predicted by phonological awareness measured at the kindergarten stage and, subsequently, by phonological memory abilities measured at the end of first grade. More precisely short‐term memory for serial‐order information seems to contribute to the development of decoding abilities, while phonological knowledge stored in long‐term memory seems to influence word recognition.  相似文献   

Face-to-face versus computer-mediated discussion of teaching cases: Impacts on preservice teachers’ engagement, critical analyses, and self-efficacy     

Lisa M. PytlikZillig  Christy A. Horn  Roger Bruning  Stephanie Bell  Xiongyi Liu  Kamau O. Siwatu  Mary C. Bodvarsson  Doyoung Kim  Deborah Carlson 《Contemporary educational psychology》2011,36(4):302-312

Two frequently-used discussion protocols were investigated as part of a program to implement teaching cases in undergraduate educational psychology classes designed for preservice teachers. One protocol involved synchronous face-to-face (FTF) discussion of teaching cases, which occurred in class after students had individually completed written case analyses as homework outside of class. The other was asynchronous computer-mediated (CM) discussion taking place outside of class, simultaneous to students’ completion of their written case analyses. Six class offerings of an undergraduate child development course taught by two instructors (three classes by each instructor) were randomly assigned within instructor in a quasi-experimental design to one of the three discussion conditions: FTF, CM, or no discussion of the cases across the semester. Findings indicated that both CM and FTF discussion conditions were associated with positive outcomes relative to the control condition. Both CM and FTF discussion related to higher cognitive–affective engagement with the cases than the control condition; and the CM discussion condition was associated with higher cognitive–affective engagement than FTF discussion. In contrast, FTF discussion, but not CM discussion, was associated with higher-than-control-condition case analysis ability at the end of the semester. Potential explanations for these findings and directions for future research are discussed.  相似文献   

Teaching Science Inquiry in Urban Contexts: The Role of Elementary Preservice Teachers’ Beliefs     

Jacqueline Leonard  Joy Barnes-Johnson  Scott Jackson Dantley  Charles Kimber 《The Urban Review》2011,43(1):124-150

This paper reports on a study of elementary preservice teachers’ inquiry-based practices, their efficacy beliefs, and the role beliefs had on two preservice teachers’ practices in urban classrooms. Results show inquiry-based practices can be cultivated through field-based experiences and preservice teachers’ efficacy beliefs, as it relates to practice in urban settings, are malleable. Specifically, personal efficacy beliefs about teaching science improved or were sustained for one cohort of preservice teachers. However, beliefs about students’ ability to learn science, that is outcome beliefs, were less stable. The results of two case studies show that science content knowledge was a factor in preservice teachers’ inquiry-based practices. However, why preservice teachers’ beliefs about student learning declined is less clear. More research is needed, along with follow-up data on teacher induction, to learn how preservice teachers’ beliefs impact urban students’ science education.  相似文献   

The kalamazoo zoo     

Jacqueline Dembar Greene 《Early Childhood Education Journal》1977,5(2):38-39

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The tennessee value-added assessment system (TVAAS): Mixed-model methodology in educational assessment     

William L. Sanders  Sandra P. Horn 《Journal of Personnel Evaluation in Education》1994,8(3):299-311

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Defending Atlanta: Press Reactions to a Movie on the Missing and Murdered Children     

Jacqueline Boles  Phillip W. Davis 《Journal of American culture (Malden, Mass. : 2003)》1988,11(3):61-66

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The impact of childhood sexual abuse in anorexia nervosa     

Carter JC  Bewell C  Blackmore E  Woodside DB 《Child abuse & neglect》2006,30(3):257-269

OBJECTIVE: The aim of this study was to examine the impact of childhood sexual abuse (CSA) on clinical characteristics and premature termination of treatment in anorexia nervosa (AN). METHOD: The participants were 77 consecutive patients with AN admitted to an inpatient eating disorders unit. The patients were assessed in terms of eating disorder symptoms, general psychopathology, and CSA history at admission to hospital. RESULTS: Thirty-seven patients (48%) reported a history of CSA before the onset of the eating disorder. Individuals with a history of CSA reported significantly greater psychiatric comorbidity, including higher levels of depression and anxiety, lower self-esteem, more interpersonal problems, and more severe obsessive-compulsive symptoms. Patients with the binge-purge subtype of AN (AN-BP) were significantly more likely to report a history of CSA prior to the onset of the eating disorder as compared with patients with the restricting subtype (AN-R) of the illness (65% of the AN-BP patients vs. 37% of the AN-R patients; p<.02). Contrary to our predictions, abused patients were not significantly more likely to dropout of treatment overall. However, patients of the binge-purge subtype (AN-BP) with a history of CSA were significantly more likely to terminate treatment prematurely as compared with the other patients. CONCLUSIONS: Consistent with previous findings, the present results indicate that the prevalence of CSA is high among individuals seeking inpatient treatment for AN. A history of CSA was associated with greater psychiatric disturbance overall and a higher rate of dropout for patients of the binge-purge subtype.  相似文献