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971.
Andrew G. Campbell Rachel Skvirsky Henry Wortis Sheila Thomas Ichiro Kawachi Christine Hohmann 《CBE life sciences education》2014,13(4):587-592
This paper summarizes the outcomes of a retreat designed to cultivate interactions between trainees at various training levels and provide them opportunities to share their training perspectives and expectations. Retreat outcomes are used to support the development of better science, technology, engineering, and mathematics training practices by informing the trainers’ perspective. 相似文献
972.
Carrie J. Boyce Chandrani Mishra Kristy L. Halverson Aimée K. Thomas 《Journal of Science Education and Technology》2014,23(6):815-826
Informal environments provide students with unique experiences that allow them to actively participate in activities while promoting a positive attitude toward and an increased interest in science. One way to enhance informal science experiences is through the integration of mobile technologies. This integration is particularly useful in engaging underrepresented students in learning science. Our informal environmental science program engages underrepresented, fifth-grade students in an informal learning environment supplemented with mobile tablet technology (iPads). The purpose of this study was to explore how fifth-grade students interacted with nature using mobile technology during a nature hike series. Participants included 55 fifth-grade students from two low-income schools. We found that students used the mobile technology to explore nature and stay engaged throughout the hike. The iPads were used as references, data collectors, and engagement tools. Students had an intense desire in returning to the site and responded positively toward interacting with nature. Prior research has indicated that students in this age group are likely to lose interest in science and the incorporation of field-friendly technology that engages students with nature, not technology alone, is a useful tool for keeping students interested in science. 相似文献
973.
974.
975.
Louise Hayward Jo-Anne Baird Simon Allan Thomas Godfrey-Faussett Carolyn Hutchinson Ellen MacIntosh Ashmita Randhawa Ernest Spencer Margaret Lesley Wiseman-Orr 《European Journal of Education》2023,58(1):83-97
Scotland, traditionally, has high levels of confidence in teachers. Fairness and justice are key concepts in policy and practice in Scottish education. For more than 100 years, the high-stakes assessment system in Scotland, with the Scottish Higher qualification at its heart, has been crucial to that sense of opportunity and justice. However, in 2019–2020, public confidence in high-stakes assessment in Scotland, as in other United Kingdom countries, was dented. In Scotland, the Covid-19 pandemic meant that schools were closed, teachers provided online learning opportunities for pupils working at home and, for the first time in 130 years, it was not possible to run national examinations. To ensure that learners were not further disadvantaged, alternative approaches to gathering evidence for qualifications were instigated. However, these results were challenged as socially unjust and the results that had been nationally moderated were replaced by results based on locally moderated teachers' professional judgement. As Scotland looks to qualifications beyond Covid-19, trust must be re-built. This article reports on a participative research project that sought to understand public perceptions of standards and fairness across a range of key communities following this experience. Drawing on both qualitative and quantitative data, we analyse factors which affected trust in National Qualifications under the pandemic. The evidence suggests that when considering what matters for qualifications to be trusted, technocratic solutions are likely to be rejected by stakeholders. Understanding and responding to what led to the mistrust of qualifications in Scotland will be crucial to inform its future qualifications system. 相似文献
976.
Thomas A. Trautner 《中国科学院院刊(英文版)》2014,(2):199-199
<正>"I participated within the CAS/MPG cooperation in the introduction of Independent Junior Research Groups at institutes of the CAS.This activity is among the most delightful and successful experiences of my scientific life.The establishment of this scientific instrument in China was determined by its scientific success in the MPG–constantly underlined by Uli Schwarz–and the groundbreaking readiness of the leadership of the CAS to pursue novel avenues of scientific organisation. 相似文献
977.
Organization of airway epithelium determines ciliary beat direction and coordination for proper mucociliary clearance. Fluidic shear stresses have the potential to influence ciliary organization. Here, an in vitro fluidic flow system was developed for inducing long-term airflow shear stresses on airway epithelium with a view to influencing epithelial organization. Our system consists of a fluidic device for cell culture, integrated into a humidified airflow circuit. The fluidic device has a modular design and is made from a combination of polystyrene and adhesive components incorporated into a 6-well filter membrane insert. We demonstrate the system operates within physiologically relevant shear and pressure ranges and estimate the shear stress exerted on the epithelial cell layer as a result of air flow using a computational model. For both the bronchial epithelial cell line BEAS2B and primary human tracheal airway epithelial cells, we demonstrate that cells remain viable within the device when exposed to airflow for 24 h and that normal differentiation and cilia formation occurs. Furthermore, we demonstrate the utility of our device for exploring the impact of exposing cells to airflow: our tool enables quantification of cytoskeletal organization, and is compatible with in situ bead assays to assess the orientation of cilia beating. 相似文献
978.
Recent advances in intergroup contact theory and research are reviewed. A meta-analysis with 515 studies and more than 250,000 subjects demonstrates that intergroup contact typically reduces prejudice (mean r = −.21). Allport's original conditions for optimal contact - equal status, common goals, no intergroup competition, and authority sanction - facilitate the effect but are not necessary conditions. There are other positive outcomes of intergroup contact, such as greater trust and forgiveness for past transgressions. These contact effects occur not only for ethnic groups but also for such other groups as homosexuals, the disabled and the mentally ill. Intergroup friendship is especially important. Moreover, these effects typically generalize beyond the immediate outgroup members in the situation to the whole outgroup, other situations, and even to other outgroups not involved in the contact. They also appear to be universal - across nations, genders, and age groups. The major mediators of the effect are basically affective: reduced anxiety and empathy. And even indirect contact reduces prejudice - vicarious contact through the mass media and having a friend who has an outgroup friend. Of course, negative contact occurs - especially when it is non-voluntary and threatening. Criticisms of the theory and policy implications are also discussed. 相似文献
979.
The automatic segmentation and classification of an unknown motion data stream according to given motion categories constitute an important research problem with applications in computer animation, medicine and sports sciences. In this paper, the scenario of trampoline motions is considered, where an athlete performs a routine consisting of sequence of jumps that belong to predefined motion categories such as pike jumps or somersaults. As main contribution, a fully automated approach for capturing, segmenting, and classifying trampoline routines according to these categories is introduced. Since trampoline motions are highly dynamic and spacious, optical motion capturing is problematic. Instead, it is reverted to a small number of inertial sensors attached to the athlete’s body. To cope with measurement noise and performance differences, suitable feature and class representations are introduced that are robust to spatial and temporal variations while capturing the characteristics of each motion category. The experiments show that the approach reliably classifies trampoline jumps across different athletes even in the presence of significant style variations. 相似文献
980.
Thomas Losnegard Håvard Myklebust Angela Ehrhardt Jostein Hallén 《Journal of sports sciences》2017,35(12):1219-1227
To characterise timing of movements and evaluate performance effects of technique alterations in V2 ski skating, 13 elite male cross-country skiers (age, 23 ± 2 years; stature, 182 ± 6 cm; body mass, 76 ± 8 kg; V2 V?O2max, 79.3 ± 4.4 mL · kg?1 · min?1) were tested four times during the preparation and competition phase on a roller ski treadmill. Each test consisted of submaximal intensities of exercise for determination of oxygen cost followed by one 1000-m performance test. Hip movement (from accelerometer data) and joint angles (2D video) were determined for high-intensity exercise (6° and 3.5 m · s?1; ~ 97–100% of V?O2peak). Each ski thrust consisted of three phases: gliding phase (18–50% of cycle time), poling phase (50–70% of cycle time), and kick phase (70–78% of cycle time). Flexion/extension of the hip initiated all phases, followed by the respective joints in legs and arms. Mixed-model analysis, adjusting for systematic time-point effects, identified that both reduced vertical hip acceleration and increased cycle time gave a small likely reduction in oxygen cost and 1000-m time. In conclusion, well-developed hip movement is a key characteristic of the V2 technique for elite-standard skiers’ long-term performance development. 相似文献