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161.
This paper presents a novel sensor technology to deduce the dynamics of a bowling ball. The sensor, a miniature wireless inertial measurement unit (IMU), incorporates MEMS accelerometers and angular rate gyros, a microcontroller, a low power RF transceiver, and a rechargeable battery. When embedded in a bowling ball, the IMU transmits the acceleration and angular velocity data that define the dynamics of the ball starting with the bowler’s delivery and its motion in the lane. Example results from professional bowlers illustrate how this technology can be used to assess bowler skill and ball performance. For instance, the IMU accurately measures the spin dynamics of the ball which are crucial to develop the ball “hook.” An analysis of ball dynamics in the lane is distilled to a measurable “hook potential” metric for further assessing bowler skill. Finally, the sensor presented herein is believed to be the world’s smallest, wireless IMU. This highly miniaturized and wireless design will enable parallel training systems for many sports, including basketball, baseball, crew, cricket, golf, fly fishing, soccer, softball, tennis, rowing, among others.  相似文献   
162.
Codes of ethics around the globe exhort archivists to neutrality so that they and their repositories will be trusted by records creators, the general public, and posterity to be impartial in their actions. However, archival neutrality is increasingly viewed as a controversial stance for a profession that is situated in the midst of the politics of memory. Archival educators have been prominent among those calling for the profession to address more directly the cultural and ethical dimensions of the role played by archives and records in society. This paper contemplates how archival neutrality and social justice concerns can surface within the context of archival education. Drawing upon experiences of the Department of Information Studies at the University of California, Los Angeles (UCLA), it suggests pedagogical approaches for raising and addressing ethics and diversity issues within a social justice framework, and for encouraging students, as future practitioners and scholars, to engage critically, reflexively, and meaningfully with these issues in ways that support the public trust in archives and the archival profession.  相似文献   
163.
Separation and sorting of biological entities (viruses, bacteria, and cells) is a critical step in any microfluidic lab-on-a-chip device. Acoustofluidics platforms have demonstrated their ability to use physical characteristics of cells to perform label-free separation. Bandpass-type sorting methods of medium-sized entities from a mixture have been presented using acoustic techniques; however, they require multiple transducers, lack support for various target populations, can be sensitive to flow variations, or have not been verified for continuous flow sorting of biological cells. To our knowledge, this paper presents the first acoustic bandpass method that overcomes all these limitations and presents an inherently reconfigurable technique with a single transducer pair for stable continuous flow sorting of blood cells. The sorting method is first demonstrated for polystyrene particles of sizes 6, 10, and 14.5 μm in diameter with measured purity and efficiency coefficients above 75 ± 6% and 85 ± 9%, respectively. The sorting strategy was further validated in the separation of red blood cells from white blood cells and 1 μm polystyrene particles with 78 ± 8% efficiency and 74 ± 6% purity, respectively, at a flow rate of at least 1 μl/min, enabling to process finger prick blood samples within minutes.  相似文献   
164.
Without the confidence and support of the medical team, this mother’s first birth was difficult and unsatisfying. She was able to give birth naturally, in the care of a midwife, with her second baby. With confidence in her ability to give birth and the wisdom that comes with experience, she is able to give birth naturally with her third baby in spite of being induced.  相似文献   
165.
This study investigates the relations between teachers’ attitudes towards persons with intellectual disability (ID), in-service training on ID, and prior contacts with persons with ID. A sample of Canadian elementary school teachers (N?=?118) completed the Attitudes Toward Intellectual Disability Questionnaire, which measures cognitive, affective and behavioural components of attitudes towards persons with ID. Correlational and multivariate regression analyses were performed. Frequent contacts with persons with ID and experience of including a child with ID increased the likelihood of reporting prior positive contacts with persons with ID. In turn, this was associated with less discomfort towards persons with ID and more willingness towards interactions. In-service training on ID was related to better knowledge of rights and capabilities of persons with ID. Experience of including a child with ID in general education classrooms increased the likelihood to report feeling competent in teaching children with ID, which predicted more willingness to include children with ID.  相似文献   
166.
It is argued that online discussion is a useful tool for creating opportunities for learning in teacher education. In a project designed to improve the practicum in rural areas, researchers placed pre-service teachers (PSTs) in two different moderated online discussion forums: an unstructured personal blog space and a structured threaded discussion forum where discussion topics guided them to reflect on their practicum experiences in relation to theoretical components of their studies. Findings indicated a marked difference in the contributions made to each form of online discussion with significantly greater participation in the unstructured blog format. Using Kreber and Cranton’s hierarchy of reflection, analyses of both forums found that PSTs rarely engaged in high-level reflection. Examination of lecturer involvement in the forums suggests that their contributions did not sufficiently encourage PSTs towards optimum critical reflection. These results leave the researchers considering ways in which the practicum experience can better promote reflective practice in this crucial, component of teacher education.  相似文献   
167.
The research reported here was focussed on accessing the perceptions of pre-service teachers regarding the critical factors which support highly effective learning in schools in the United Kingdom. Their perceptions were arranged into a taxonomy so that they can be used as a starting point for their reflections on the observations they make of teaching and learning in schools with the aim of enhancing the effectiveness of their own teaching. The choice of technique used to access the perceptions was driven by the desire to provide the pre-service teachers with a method that they could use themselves to engage with the ‘voice’ of their own pupils regarding the factors which support effective learning. The engagement of pupil voice has become increasingly significant in understanding effective pedagogy and in securing more personalised approaches to learning in United Kingdom school contexts.  相似文献   
168.
Using collaborative performance ethnography in community- and school-based settings, sex education has the potential to challenge at-risk narratives for lesbian, gay, bisexual, transgender, intersex and queer (LGBTIQ) youth. This paper problematises the youth-led drama project Epic Queer to test the ‘queer’ potential of youth-driven initiatives at the school and community level, and to reject the singularity of victimised and ‘at-risk’ narratives so pervasive in sex education internationally about queer youth. By drawing on the It Gets Better Project as an example of widespread but narrowing social media texts encouraging normativity, deferred pleasure and a happiness narrative, this paper argues for the potential of performance-based arts engagement for re-expanding queer youth subjectivities.  相似文献   
169.
Against the backdrop of the recent political discourse on elite and excellence in the German education system, this paper examines how such constructions manifest themselves in programmatic concepts of schools and in the orientations of their pupils and their peers. They are reconstructed on the basis of a qualitative research project on educational careers of young people. This paper focuses on pupils and their peers at an elite school of sports and an international school. Firstly, the state of research on those types of school as well as on educational careers of their pupils will be presented. Secondly, the theoretical reference points and the methodological design of the study will be introduced. At the core of the paper is the analysis of the education related orientations of selected cases of young people and their peers: How do they position themselves towards elite and excellence in their individual and collective orientations and how is this relevant for processes of distinction and coherence building in the groups? In the resuming part of the paper, the results will be summarised and related to the state of research and the scientific discourse on elite and excellence.  相似文献   
170.
The majority of eukaryotic genes produce multiple mRNA isoforms with distinct 3′ ends through a process called mRNA alternative polyadenylation (APA). Recent studies have demonstrated that APA is dynamically regulated during development and in response to environmental stimuli. A number of mechanisms have been described for APA regulation. In this review, we attempt to integrate all the known mechanisms into a unified model. This model not only explains most of previous results, but also provides testable predictions that will improve our understanding of the mechanistic details of APA regulation. Finally, we briefly discuss the known and putative functions of APA regulation.  相似文献   
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