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911.
Fu YQ Garcia-Gancedo L Pang HF Porro S Gu YW Luo JK Zu XT Placido F Wilson JI Flewitt AJ Milne WI 《Biomicrofluidics》2012,6(2):24105-2410511
Surface acoustic wave (SAW) devices with 64 μm wavelength were fabricated on a zinc oxide (ZnO) film deposited on top of an ultra-smooth nanocrystalline diamond (UNCD) layer. The smooth surface of the UNCD film allowed the growth of the ZnO film with excellent c-axis orientation and low surface roughness, suitable for SAW fabrication, and could restrain the wave from significantly dissipating into the substrate. The frequency response of the fabricated devices was characterized and a Rayleigh mode was observed at ∼65.4 MHz. This mode was utilised to demonstrate that the ZnO/UNCD SAW device can be successfully used for microfluidic applications. Streaming, pumping, and jetting using microdroplets of 0.5 and 20 μl were achieved and characterized under different powers applied to the SAW device, focusing more on the jetting behaviors induced by the ZnO SAW. 相似文献
912.
Professional, workplace searching is different from general searching, because it is typically limited to specific facets and targeted to a single answer. We have developed the semantic component (SC) model, which is a search feature that allows searchers to structure and specify the search to context-specific aspects of the main topic of the documents. We have tested the model in an interactive searching study with family doctors with the purpose to explore doctors’ querying behaviour, how they applied the means for specifying a search, and how these features contributed to the search outcome. In general, the doctors were capable of exploiting system features and search tactics during the searching. Most searchers produced well-structured queries that contained appropriate search facets. When searches failed it was not due to query structure or query length. Failures were mostly caused by the well-known vocabulary problem. The problem was exacerbated by using certain filters as Boolean filters. The best working queries were structured into 2–3 main facets out of 3–5 possible search facets, and expressed with terms reflecting the focal view of the search task. The findings at the same time support and extend previous results about query structure and exhaustivity showing the importance of selecting central search facets and express them from the perspective of search task. The SC model was applied in the highest performing queries except one. The findings suggest that the model might be a helpful feature to structure queries into central, appropriate facets, and in returning highly relevant documents. 相似文献
913.
Alastair Wilson 《Metascience》2012,21(1):143-146
914.
Sides D Wilson C 《Sports biomechanics / International Society of Biomechanics in Sports》2012,11(1):1-9
This study aimed to establish the nature of lower extremity intra-limb coordination variability in cycling and to investigate the coordinative adaptations that occur in response to changes in cadence and work rate. Six trained and six untrained males performed nine pedalling bouts on a cycle ergometer at various cadences and work rates (60, 90, and 120 revolutions per minute (rpm) at 120, 210, and 300W). Three-dimensional kinematic data were collected and flexion/extension angles of the ankle, knee, and hip joints were subsequently calculated. These data were used to determine two intra-limb joint couplings [hip flexion/extension-knee flexion/extension (HK) and knee flexion/extension-ankle plantar-flexion/dorsi-flexion (KA)], which were analysed using continuous relative phase analysis. Trained participants displayed significantly (p < 0.05) lower coordination variability (6.6 +/- 4.0 degrees) than untrained participants (9.2 +/- 4.7 degrees). For the trained subjects, the KA coupling displayed significantly more in-phase motion in the 120 rpm (19.2 +/- 12.3 degrees) than the 60 (30 +/- 7.1 degrees) or 90 rpm (33.1 +/- 7.4 degrees) trials and the HK coupling displayed significantly more in-phase motion in the 90 (33.3 +/- 3.4 degrees) and 120 rpm (27.9 +/- 13.6 degrees) than in the 60 rpm trial (36.4 +/- 3.5 degrees). The results of this study suggest that variability may be detrimental to performance and that a higher cadence is beneficial. However, further study of on-road cycling is necessary before any recommendations can be made. 相似文献
915.
Susan Berney Kimberley Haines Linda Denehy 《Cardiopulmonary Physical Therapy Journal》2012,23(1):19-25
A physiotherapist is part of the multidisciplinary team in most intensive care units in Australia. Physiotherapists are primary contact practitioners and use a comprehensive multisystem assessment that includes the respiratory, cardiovascular, neurological, and musculoskeletal systems to formulate individualized treatment plans. The traditional focus of treatment has been the respiratory management of both intubated and spontaneously breathing patients. However, the emerging evidence of the longstanding physical impairment suffered by survivors of intensive care has resulted in physiotherapists re-evaluating treatment priorities to include exercise rehabilitation as a part of standard clinical practice. The goals of respiratory physiotherapy management are to promote secretion clearance, maintain or recruit lung volume, optimize oxygenation, and prevent respiratory complications in both the intubated and spontaneously breathing patient. In the intubated patient, physiotherapists commonly employ manual and ventilator hyperinflation and positioning as treatment techniques whilst in the spontaneously breathing patients there is an emphasis on mobilization. Physiotherapists predominantly use functional activities for the rehabilitation of the critically ill patient in intensive care. While variability exists between states and centers, Australian physiotherapists actively treat critically ill patients targeting interventions based upon research evidence and individualized assessment. A trend toward more emphasis on exercise rehabilitation over respiratory management is evident.Key Words: physiotherapy, intensive care 相似文献
916.
Terri S. Wilson 《Educational theory》2010,60(6):643-664
In this essay, Terri Wilson puts the argument developed by Kathleen Knight Abowitz that charter schools could be considered as counterpublic spaces into interaction with empirical research that explores patterns of voluntary self‐segregation in charter schools. Wilson returns to the theoretical tension between Jürgen Habermas and Nancy Fraser over the inclusivity of the public sphere. Wilson argues that Fraser's concept of counterpublic space rests on an oversimplification of Habermas's concept of the public sphere and, further, that justifying school choice through Fraser's “multiplicity of publics” offers few resources for questioning the increasing segregation of schools. According to Wilson, Habermas's normative project—and his concept of “idealization,” in particular—offers both an answer to Fraser's critique and a better application of “the public sphere” to the issue of school choice. Wilson concludes by considering how Habermas's understanding of the public sphere as a normative ideal might serve as a useful resource for evaluating the public‐ness of charter school reform. 相似文献
917.
Reading and writing from multiple source documents in history: Effects of strategy instruction with low to average high school writers 总被引:2,自引:0,他引:2
This study examined the effects of historical reasoning strategy instruction on 11th-grade students. Students learned historical inquiry strategies using 20th Century American history topics ranging from the Spanish-American war to the Gulf of Tonkin incident. In addition, students learned a pre-writing strategy for composing argumentative essays related to each historical event. Results indicate that in comparison to a control group (N = 79), essays written by students who received instruction (N = 81) were longer, were rated as having significantly greater historical accuracy, were significantly more persuasive, and claims and rebuttals within each argument became more elaborated. Importantly, students in the control group read the same primary and secondary source document sets, and received feedback on written essays on the same topics. 相似文献
918.
919.
教育政策和实践总是处在困境之中,这是困扰政策制定者和实践者的问题.本文着力从教育政策和实践所面临的困境、如何处理困境的角度,重新审视政策和实践两者的关系,并从政策目标、政策工具和实践中的能力三方面对其展开论述,以期在冲突的基础上促进教育政策和实践间的融合. 相似文献
920.
Becoming “Effective” Citizens? Change-Oriented Service in a Teacher Education Program 总被引:1,自引:0,他引:1
The authors investigated the impact of 22 pre-service teachers’ participation in a change-oriented service-learning project
on their conceptions of citizenship as civic actors and civic educators. The goal of this project was to push students toward
adopting more critically conscious and activist conceptions of citizenship as aligned with the needs of a democratic society.
Using Eyler and Giles’ (1999) typology of effective citizenship as an analytic framework, we describe how students’ participation
in this project led to demonstrated growth along all five dimensions of effective citizenship. Yet, analysis revealed that,
despite the project’s change-orientation, students’ conceptions of citizenship failed to move beyond personal responsibility
to include enhanced social consciousness and the importance of collective action. Thus, we raise critical questions about
what constitutes “effective citizenship” in a democratic society and the role of higher education in preparing teachers to
embody and enact such a vision. 相似文献