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11.
The problem of teacher incompetence is a serious one, affecting large numbers of American public school students. There is a significant discrepancy between estimated rates of incompetent teachers and the number of teachers actually dismissed on grounds of incompetence. This study sought to uncover the perceptions of teachers regarding a definition of professional incompetence, strategies used with incompetent teachers, and barriers to the dismissal process, through the use of a survey with more than 200 elementary school teachers in Virginia and follow-up interviews with seven of these participants. The researcher found that teachers rated classroom behaviors to be the most important factors towards a definition of professional incompetence. The teachers involved also rated the commonness of strategies used with incompetent teachers, placing dismissal among the least common actions taken by administrators, and revealed that they believed union protection, legal and other expenses, and difficulty providing documentation prevented administrators from dismissing incompetent teachers.  相似文献   
12.
In this paper, we present an on-chip hand-powered membrane pump using a robust patient-to-chip syringe interface. This approach enables safe sample collection, sample containment, integrated sharps disposal, high sample volume capacity, and controlled downstream flow with no electrical power requirements. Sample is manually injected into the device via a syringe and needle. The membrane pump inflates upon injection and subsequently deflates, delivering fluid to downstream components in a controlled manner. The device is fabricated from poly(methyl methacrylate) (PMMA) and silicone, using CO2 laser micromachining, with a total material cost of ∼0.20 USD/device. We experimentally demonstrate pump performance for both deionized (DI) water and undiluted, anticoagulated mouse whole blood, and characterize the behavior with reference to a resistor-capacitor electrical circuit analogy. Downstream output of the membrane pump is regulated, and scaled, by connecting multiple pumps in parallel. In contrast to existing on-chip pumping mechanisms that typically have low volume capacity (∼5 μL) and sample volume throughput (∼1–10 μl/min), the membrane pump offers high volume capacity (up to 240 μl) and sample volume throughput (up to 125 μl/min).  相似文献   
13.
14.
Purpose: The limited uptake of improved agricultural practices in Africa raise questions on the functionality of current agricultural research systems. Our purpose is to explore the capacity for local innovation within the research systems of Ethiopia, Malawi and Mozambique.

Design/methodology/approach: Using Conservation Agriculture (CA) as a case study, we qualitatively explore with 26 locally based agricultural researchers the context of CA research and promotion, including their perceptions on persistent research gaps and issues in closing them.

Findings: Respondents identified that CA was not yet a finished product, with concerns regarding the benefit, feasibility and relevance of CA implementation. They asserted that while further adaptation was required, they were unable to do this due to institutional constraints within their research, extension and policy contexts.

Practical implications: We find that CA continues to be considered a donor-driven intervention in its current form and requires substantial further adaptation to local contexts before researchers will deem it ready for farmer uptake. The five research gaps identified by respondents highlight practical areas where further adaptations must occur.

Theoretical implications: Our findings suggest a lack of participatory research and extension most likely reflects limited financial, human and social capital to implement more participatory approaches. Without addressing these capacities, widespread adoption of complex farming systems change appears unlikely.

Originality/Value: Whilst many studies have identified a need for local innovation to enable CA utilisation, few have qualitatively explored directly with local researchers the capacity of such systems to do so. We address this gap in the literature.  相似文献   

15.
Today, Zambia has a comparatively unified, somewhat exceptional, approach to religious education despite a wide variety of predominantly Christian denominations. This article retraces the history of the development of religious education from when it was entirely confessional to the present time when it has become largely educational. In so doing it identifies some of the difficulties encountered and some of the problems that lie ahead in promoting an even more religiously pluralistic and educational approach to religious education in a country that has been declared a Christian nation.  相似文献   
16.
Lower limb amputees often experience complications with the use of conventional socket-type prostheses, which further reduce their already compromised ability to perform the activities of daily living, or to participate in sporting activities. During the last two decades, a new technology of direct skeletal attachment (osseointegration) of prosthesis to the femoral residuum has been developed. The aim of this research was to assess the implant design, surgery protocols, and functional testing of this new technology on the first 100 patients using the Integral Leg Prosthesis procedure. This new knowledge can guide future engineering developments of osseointegration within the sporting arena. Between 1999 and 2013, direct skeletal implantation was performed on 112 amputees, from two centres in Germany and Australia. From the experience of the surgical team, modifications were made to the implant design. This re-engineering of the implant has reduced the surgical revisions due to infection from 29 % with the early implant design down to 7 %. The functional testing of the 34 Australian cases were assessed pre- and 12 months post-implant with significant improvements of one complete K-scale; the Q-TFA measures increased (50.9–86.7), whilst the Timed Up and Go decreased significantly (12.43 s ± 3.89 to 8.03 s ± 2.80), and the 6 min walk increased (304.0–383.9 m). From these findings, osseointegration technology is realistically the way of the future for amputee athletes. Further refinement of the implant design and sports-specific functional testing are required to define the potential of this technology.  相似文献   
17.
This study examined the skill involvements of three positional groups across a junior representative rugby league season. Data were collected from 45 rugby league players (mean ± SD; age = 16.5 ± 1.0 years) currently participating in the Harold Matthews and SG Ball Cup. Players were subdivided into hit-up forwards, adjustables and outside backs. The frequency (n · min?1) of offensive, defensive and overall involvements was coded for each group using a notation system and a practical coach skill analysis tool. Multivariate analysis of variance (MANOVA) revealed a significant effect of playing position on skill involvements (F = 9.06; P < 0.001; ES = 0.41). Hit-up forwards performed a significantly greater frequency of offensive (0.31 ± 0.10), defensive (0.42 ± 0.15) and overall involvements (0.74 ± 0.19) when compared to adjustables (0.20 ± 0.08, 0.28 ± 0.08 and 0.52 ± 0.15, respectively) and outside backs (0.20 ± 0.12, 0.11 ± 0.07 and ± 0.31 ± 0.17, respectively). Further, adjustables performed a significantly greater number of defensive (0.28 ± 0.08) and overall involvements (0.52 ± 0.15) when compared to outside backs (0.11 ± 0.07 and 0.31 ± 0.17, respectively). The findings of this study suggest that it is important to consider a junior player’s positional group when analysing their skill involvements. Information gained from this study could assist in the design of specific training methodologies for junior rugby league players in high-level talent development programmes.  相似文献   
18.
This study employed an explanatory mixed methods design to examine the effects of two computer-based scaffolds on novice teachers’ reflective journal writing. The context for the study was an attempt to refine the reflective writing component of a large scale electronic portfolio system. Quantitative results indicated that the computer-based scaffolds significantly enhanced the participants’ reflective journal writing as well as the length of their written artifacts. Moreover, correlation analysis revealed that there was a positive relationship between the highest level of reflection and the length of journal writing. Three factors gleaned from qualitative data helped explain how and why the scaffolds enhanced participants’ reflective thinking, including (a) the specific requirements conveyed in the scaffolds; (b) the structure of the scaffolds; and (c) the use of the critical incidents to anchor reflective journal writing. It is hoped that the analyses and results of the current study can help inform others on how to leverage the affordances of computer-based scaffolds to augment reflective practice in technology-enhanced educational systems.  相似文献   
19.
Brendan Haley 《Research Policy》2018,47(6):1147-1160
This paper augments the technological innovation systems (TIS) framework to provide policy guidance on how to manage interactions between a core technology and its larger sectoral context. A TIS development cycle is presented that combines the TIS framework’s ability to clearly illuminate policy gaps with Erik Dahmén’s idea that technological diffusion creates structural tensions that introduce transformation pressure. This pressure can result in stagnation and unrealized development potential or spur sectoral complementarities and the evolution of a TIS into a larger “development block” of interlinked technological systems. Integrating structural tensions into TIS analysis highlights how the evolution of a focal technology induces technological complementarities and creates a need to continuously re-design policies. This underscores the continued benefit of a technology system perspective, even as a technology matures.The revised TIS framework is applied to a case study of the Canadian province of Nova Scotia that explores how variable renewable electricity diffusion introduces structural tensions with existing electricity grids, requiring the use of complementary technologies that add storage and flexibility. Nova Scotia aggressively developed wind energy and built a high-voltage direct-current transmission line to import hydroelectricity that could back-up variable renewable energy sources like wind.  相似文献   
20.
Abstract

The drop jump is a popular form of plyometric exercise often undertaken to enhance countermovement jump ability (jump height). Despite its popularity the effects of drop jump training on countermovement jump height are often inconsistent. Such inconsistencies may be as a result of differences in the drop jump technique being employed. Two recognised forms of drop jump are the “countermovement” drop jump and the “bounce” drop jump and the current study examined the effects of eight weeks of training with these drop jump techniques on countermovement jump height. Methods: A kinetic and kinematic analysis of each participant's countermovement jump, bounce- and countermovement drop jumps was undertaken prior to training. Participants were then randomly assigned to a bounce drop jump training group (n = 34), a countermovement drop jump training group (n = 35) or a control group (n = 34). Changes in jump height were examined following training. Results: The countermovement drop jump training group increased their countermovement jump height by 2.9 cm (6%), which was a significant change (P < 0.05) in comparison to that experienced by the bounce drop jump (-0.2 cm, -0.4%) and the control group (-0.1 cm, 0.2%). Conclusion: The countermovement drop jump may be more effective than the bounce drop jump at enhancing countermovement jump height.  相似文献   
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