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511.
Creating public value is a key goal of public administrations, both in their daily business and in the growing field of smart government and smart cities, which focuses on IT-enabled innovations in the public sphere. However, many public administrations still struggle with such innovations due to complex technologies, high investments, and the numerous stakeholders involved. To address this issue, some local governments in continental Europe have turned to collaborative innovation approaches, partnering with (semi-)public utility companies in the hope that their additional innovation assets will boost innovativeness. Nevertheless, it remains unclear how exactly such collaborations should be governed to ensure that the focus remains on creating public value, as utility companies may have their own agendas. To explore this question, we conducted a comparative case study in the context of smart city initiatives with four cases in Swiss local governments. Drawing on agency and stewardship theory, we then propose a model of public-value-focused collaborative innovation, enabling us to explore various collaboration characteristics and their effects on public value creation. Our findings suggest that both agency- and stewardship-based collaborations increase innovativeness. However, while agency collaborations tend to produce smart city innovations that mainly serve the utility companies' business interests, stewardship relationships lead to innovations that are focused more on public value creation. As such, our study extends the literature on the effects of collaborative innovation on public value, and it provides practical recommendations on how such collaborative innovation should be designed.  相似文献   
512.
Educational technology is increasingly used in multicultural contexts and across national cultures. Educational technology users with different national and professional backgrounds may, however, exhibit different attitudes towards technology. Previous research provides isolated evidence of the relationship between learning technology acceptance and culture, and so an overall picture is missing. Therefore, this study attempts to integrate culture (sensu Hofstede) into an established technology acceptance model (ie, Venkatesh's Unified Theory of Acceptance and Use of Technology, UTAUT). Examining a large sample (n = 2866) of learning technology users from Germany and Romania by means of questionnaire survey, we investigate the differences in culture and technology acceptance between sample subgroups. The collected data reveal the presence of cultural differences both between countries and between professions. In line with previous research, these differences are associated with dissimilar acceptance profiles, ie, different values of acceptance variables and of path coefficients between them. Based on the findings, this study makes headway in cross‐cultural research by proposing an extended model of UTAUT—one which integrates three of Hofstede's culture dimensions. As a practical implication, national and professional culture may shape computer‐based learning environments.  相似文献   
513.
研究目的:评价含有酪蛋白磷酸肽-无定形磷酸钙(CPP-ACP)的再矿化剂Tooth Mousse(TM)的使用、不同玷污层的处理以及样本储存时间对牙本质粘接微拉伸性能的影响。研究方法:将牙本质样本分成保留玷污层组和用15%乙二胺四乙酸(EDTA)处理90秒去除玷污层组。每组根据是否使用TM处理再分亚组。每个亚组分别用三种不同的粘结剂(两步法自酸蚀Clearfil SE Bond(CSE)、一步法自酸蚀G-Bond(GB)和全酸蚀Adper Single Bond 2(SB))与牙本质样本粘接,分别经过3天和6个月的去离子水储存。样本进行切割微拉伸测试并通过扫描电镜分析断裂界面模式。重要结论:经过再矿化剂TM预处理,可以减少牙齿的敏感性,并且对于这三种粘结系统经过长时间储存后的粘结性能没有影响。EDTA的处理对于长期储存的粘结性能没有显著影响。额外的TM和EDTA对短期(3天)粘接力会有效应,但对长期(6个月)的粘接力没有影响。  相似文献   
514.
Identification of core competencies for undergraduates in food safety is critical to assure courses and curricula are appropriate in maintaining a well‐qualified food safety workforce. The purpose of this study was to identify and refine core competencies relevant to postsecondary food safety education using a modified Delphi method. Twenty‐nine experts representing food safety professionals in academia, government, and industry were given 2 rounds of questionnaires that specified initial food safety competencies, core domains, and subdomains. Competencies were defined as a set of skills, knowledge, and abilities that correlate to success of a trainee. The framework for which competencies were classified consisted of (1) core domains, defined as broad food safety subjects; and (2) subdomains, or more specific food safety subjects. The expert panel used a 5‐point Likert scale with an acceptance criterion, or consensus, of 75%, with a rating of “4” or greater. After 2 rounds of questionnaires and revisions from the expert panel, 5 core domains were established: (1) Food Production, Manufacturing, Retail, and Consumer; (2) Foodborne Hazards; (3) Public Health; (4) Legislation and Policy; and (5) Communication and Education. Specific responses from the experts highlighted areas in which further curriculum revision would be beneficial. This study provides a framework for the development of a vetted, standardized undergraduate food safety curriculum. The Delphi method, with its inclusion of professionals representing various sectors of food safety, provided relevant perspectives for curriculum design, and also allowed participants the opportunity to contribute to the education of future food safety professionals.  相似文献   
515.

The purpose of this paper is to highlight how I use images from teen magazines to engage girls in critical inquiry about the body. This process is about co-constructing bodily knowledge and reflecting critically on this knowledge. The analysis is broken into three main parts: (a) tapping girls' interests; (b) helping girls name how they experience their bodies; and (c) using images to critique dominant stories of the body. Within each of these sections, I will foreground the process by looking at the curricular tasks as well as the verbal engagement through which the girls and I negotiated the tasks together. The data are used to illustrate the pedagogical possibilities of engaging girls in critical inquiry on body. I conclude the paper by discussing the pedagogical possibilities for studying the body with adolescent girls that emerged and reflect critically on the struggles involved in the process of engaging girls in critical inquiry.  相似文献   
516.
This study examines the utility of current accelerometer threshold definitions and epoch durations for physical activity intensity classification in preschool-aged children. Using video footage of children engaged in active play, directly observed 1-sec epoch physical activity intensity scores were derived from a modified version of the Children's Activity Rating Scale, averaged into 15-sec epochs (corresponding to the accelerometer scale), and compared to accelerometer-measured classifications. Overall, 6,540 individual 1-sec epochs were captured and classified from six children, yielding 429 time-matched 15-sec epoch physical activity intensity classifications from both methods. Children participated in 25 distinct physical activity behaviors and spent 75% of free-play in one intensity level for ≤5 sec. The maximum amount of time spent participating in an activity prior to changing activity intensity was 98 sec. Agreement between methods was generally poor (overall: κ = .22; child range: κ = .00 to .66), and the difference between methods was significantly asymmetrical (McNemar's test overall: p = .01). Accelerometer thresholds and epoch durations used to classify preschoolers' physical activity intensity yielded biased estimates in the current study. Further investigation is necessary to establish optimal physical activity measurement methods with this population.  相似文献   
517.
The purpose of this study was to quantify the inter-session reliability of force–velocity–power profiling and estimated maximal strength in youth. Thirty-six males (11–15 years old) performed a ballistic supine leg press test at five randomized loads (80%, 100%, 120%, 140%, and 160% body mass) on three separate occasions. Peak and mean force, power, velocity, and peak displacement were collected with a linear position transducer attached to the weight stack. Mean values at each load were used to calculate different regression lines and estimate maximal strength, force, velocity, and power. All variables were found reliable (change in the mean [CIM] = ? 1 to 14%; coefficient of variation [CV] = 3–18%; intraclass correlation coefficient [ICC] = 0.74–0.99), but were likely to benefit from a familiarization, apart from the unreliable maximal force/velocity ratio (CIM = 0–3%; CV = 23–25%; ICC = 0.35–0.54) and load at maximal power (CIM = ? 1 to 2%; CV = 10–13%; ICC = 0.26–0.61). Isoinertial force–velocity–power profiling and maximal strength in youth can be assessed after a familiarization session. Such profiling may provide valuable insight into neuromuscular capabilities during growth and maturation and may be used to monitor specific training adaptations.  相似文献   
518.
未来气候变化对鄱阳湖区土地利用变化的影响评估   总被引:2,自引:0,他引:2  
为了评估未来气候变化可能对鄱阳湖区土地利用变化产生的影响,本文根据IPCC的建议,利用新近建立的基于主体的土地利用变化模拟模型,详细分析了4种气候变化情景下鄱阳湖区1985-2035年的土地利用变化过程。这4种气候变化情景分别为A1B(经济高速增长模式)、A2(区域经济多样化增长模式)、B1(引进更多清洁能源的经济增长模式)和情景4(无气候变化模式)。在这些气候变化情景中,由于耕地的农业生产潜力差异显著,农户主体的收入和他们对土地利用方式的决策也发生了相应的改变。通过对这一过程的模拟和结果分析,发现气候变化可能有利于鄱阳湖区土地利用变化向着环境友好的方向自我调整。与A1B和A2两种气候变化情景相比,B1情景对土地利用变化的影响更具环境友好性。  相似文献   
519.

Introduction

Technological innovation requires the laboratories to ensure that modifications or incorporations of new techniques do not alter the quality of their results. In an ISO 15189 accredited laboratory, flexible scope accreditation facilitates the inclusion of these changes prior to accreditation body evaluation. A strategy to perform the validation of a biochemistry analyzer in an accredited laboratory having a flexible scope is shown.

Materials and methods:

A validation procedure including the evaluation of imprecision and bias of two Dimension Vista analysers 1500 was conducted. Comparability of patient results between one of them and the lately replaced Dimension RxL Max was evaluated. All studies followed the respective Clinical and Laboratory Standards Institute (CLSI) protocols. 30 chemistry assays were studied. Coefficients of variation, percent bias and total error were calculated for all tests and biological variation was considered as acceptance criteria. Quality control material and patient samples were used as test materials. Interchangeability of the results was established by processing forty patients’ samples in both devices.

Results:

27 of the 30 studied parameters met allowable performance criteria. Sodium, chloride and magnesium did not fulfil acceptance criteria. Evidence of interchangeability of patient results was obtained for all parameters except magnesium, NT-proBNP, cTroponin I and C-reactive protein.

Conclusions:

A laboratory having a well structured and documented validation procedure can opt to get a flexible scope of accreditation. In addition, performing these activities prior to use on patient samples may evidence technical issues which must be corrected to minimize their impact on patient results.  相似文献   
520.
Proprioceptive Neuromuscular Facilitation ‐ patterns and techniques D.E. Voss, M.K. Ionta and B.J. Myers. Harper and Row, Philadelphia, 1985 xxvi + 370 pp, £29.95, ISBN 0 06 142595 8

Science of Stretching M.J. Alter, Human Kinetics, Champaign, Illinois, 1988 xii + 243 pp, $26.00, ISBN 0 87322 090 0  相似文献   
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