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841.
There has been extensive research internationally describing teachers’ homogenous socio-demographic backgrounds and critiquing the associated equity and diversity issues, most especially with regard to ethnicity and gender, and to a lesser extent, social class and disability. Yet, teachers’ religious affiliations and/or convictions have rarely been explored. Since 96% of state primary schools in Ireland are denominational, considering religious diversity in teaching is both critically important and a complex undertaking. This paper examines primary initial teacher education (ITE) applicants’ religiosity, and views of teaching religion, in Ireland. Our data suggest low levels of religious practice and religiosity among ITE applicants, many of whom would prefer to teach religion using a non-confessional approach. The paper raises critical questions regarding the experiences, constitutional rights and professional practice of increasingly secular and/or non-practicing Catholic teacher cohorts in a predominantly Catholic primary education system that has survived the trend towards progressive ‘unchurching’ of Europe.  相似文献   
842.
This article proposes a process to retrieve the URL of a document for which metadata records exist in a digital library catalog but a pointer to the full text of the document is not available. The process uses results from queries submitted to Web search engines for finding the URL of the corresponding full text or any related material. We present a comprehensive study of this process in different situations by investigating different query strategies applied to three general purpose search engines (Google, Yahoo!, MSN) and two specialized ones (Scholar and CiteSeer), considering five user scenarios. Specifically, we have conducted experiments with metadata records taken from the Brazilian Digital Library of Computing (BDBComp) and The DBLP Computer Science Bibliography (DBLP). We found that Scholar was the most effective search engine for this task in all considered scenarios and that simple strategies for combining and re-ranking results from Scholar and Google significantly improve the retrieval quality. Moreover, we study the influence of the number of query results on the effectiveness of finding missing information as well as the coverage of the proposed scenarios.  相似文献   
843.
The technology acceptance model (TAM) has been widely used to study user acceptance of new computer technologies. However, it does not incorporate social structure and influence as a significant factor. In this study, we ask the following questions: (i) What are the limitations of the existing TAM for studying virtual community? (ii) What is effect of social networks on user acceptance of technology for virtual community? and (iii) How can the influence of different types of social ties serve as a basis for exploring the user acceptance of technology in a virtual community? Here, we explore the possibility for extending TAM to incorporate the influence of the different types of social ties as a new theoretical construct. Preliminary analysis of data from a virtual community results show that weak and strong ties influence technology acceptance. The findings enable HCI researchers to account for influence of social ties in future investigations using TAM.  相似文献   
844.
In the United Kingdom, information and communication technologies are being used to e-enable multiagency community services for children. Public policy advocates that practitioners as well as users should be involved in the shaping of services including the information systems used in their delivery. This article discusses how a group of social and computer scientists developed the social formation methodology to facilitate nonexpert community participation in the design of e-enabled community care services. The longitudinal study adapts qualitative methods to understand community welfare and to foster participation in the design of communication systems. By exploring the perspectives of welfare practitioners and families, the importance of situated and mediated conversations in community care is identified. The facilitative conversation approach of the study then brings these community perspectives, as well as ICT perspectives, into design processes of e-enabled services.  相似文献   
845.
SEAD method estimates the direction-of-arrival angles on an uniform linear array based on the difference between the two largest singular values, what is called differential spectrum. Although it presented an outstanding performance, the ability to indicate the source positions was not elucidated yet. Inspired by the differential spectrum formulation we derived a total differential spectrum and found out that the matrix norm induced by the vector 2-norm of a modified spatial covariance matrix can be used to estimate the direction-of-arrival of multiple plane waves. Indeed we show that matrix norms are estimators and we propose their use instead of the singular value decomposition in SEAD-based methods. We present a general mathematical expression in order to explicit the operating principles of the proposed methods. Consequently, we were able to explain how the relation between the arriving and the search angles produces the larger peaks on the differential spectrum. To evaluate the important role played by matrix norms, a thousand experiments were carried out. They showed that the proposed approach proved to be as accurate as the previous SEAD-based methods, while providing a significant reduction on runtime. It also outperformed well-established methods like MODEX regarding the estimation error.  相似文献   
846.
Animal toxins that are used to subdue prey and deter predators act as the key drivers in natural food chains and ecosystems. However, the predators of venomous animals may exploit feeding adaptation strategies to overcome toxins their prey produce. Much remains unknown about the genetic and molecular game process in the toxin-dominant food chain model. Here, we show an evolutionary strategy in different trophic levels of scorpion-eating amphibians, scorpions and insects, representing each predation relationship in habitats dominated by the paralytic toxins of scorpions. For scorpions preying on insects, we found that the scorpion α-toxins irreversibly activate the skeletal muscle sodium channel of their prey (insect, BgNaV1) through a membrane delivery mechanism and an efficient binding with the Asp/Lys-Tyr motif of BgNaV1. However, in the predatory game between frogs and scorpions, with a single point mutation (Lys to Glu) in this motif of the frog''s skeletal muscle sodium channel (fNaV1.4), fNaV1.4 breaks this interaction and diminishes muscular toxicity to the frog; thus, frogs can regularly prey on scorpions without showing paralysis. Interestingly, this molecular strategy also has been employed by some other scorpion-eating amphibians, especially anurans. In contrast to these amphibians, the Asp/Lys-Tyr motifs are structurally and functionally conserved in other animals that do not prey on scorpions. Together, our findings elucidate the protein-protein interacting mechanism of a toxin-dominant predator-prey system, implying the evolutionary game theory at a molecular level.  相似文献   
847.
The Integrated Food Safety Centers of Excellence aim to develop novel learning methods to educate and train the future public health workforce to investigate foodborne outbreaks. The Foodborne Outbreak Challenge (FOC) was a one‐day event hosted by the Colorado Integrated Food Safety Center of Excellence at the Colorado School of Public Health. The FOC incorporated experiential, problem‐based, and interdisciplinary pedagogies from case studies, simulation exercises, and public health case competitions, to deliver a novel learning experience that met the training needs of a multidisciplinary foodborne outbreak response team with diverse skills sets. The event received positive feedback, and participants demonstrated knowledge gain. Event materials are available for other institutions to use.  相似文献   
848.
849.
Little is known about the association between environmental characteristics and types of physical activity in adolescents in a Latin American context. The aim of this study was to examine the association between perceived neighborhood environmental characteristics and different types of physical activity in 2,874 adolescents from Joao Pessoa, Paraiba State, Northeastern Brazil. The types of activity measured by questionnaire (≥10 min/day) included sports, physical exercises, active commuting and recreational activities. Neighborhood characteristics were measured by a 15-item scale. Multilevel analyses showed that adolescents who reported “having places they liked to go to” (OR = 1.41; 95%CI: 1.10–1.79) and “places with opportunities to practice” (OR = 1.29; 95%CI: 1.01–1.65) were more likely to play sports. “Seeing interesting things while walking” (OR = 1.24; 95%CI: 1.01–1.53) and “Seeing other adolescents engaged in physical activity” (OR = 1.47; 95%CI: 1,05–2,06) were associated with exercises. “Seeing other adolescents engaged in physical activity” (OR = 1.47; 95%CI: 1.18–1.82), “the neighborhood is not violent” (OR = 1.29; 95%CI: 1.04–1.60) and “having places they like to go to” (OR = 1.59; 95%CI: 1.13–2.25) were positively associated and “places with opportunities to practice” (OR = 0.79; 95%CI: 0.63–0.98) inversely related to active commuting. “Seeing other adolescents engaged in physical activities” (OR = 1.31; 95%CI: 1.05–1.63) and “seeing interesting things while walking” (OR = 1.26; 95%CI: 1.02–1.56) were associated with recreational activities. Neighborhood environmental characteristics associated with the physical activity vary with the type of practices adopted by adolescents.  相似文献   
850.
Jump performance is considered an important factor in many sports. Thus, strategies such as weightlifting (WL) exercises, traditional resistance training (TRT) and plyometric training (PT) are effective at improving jump performance. However, it is not entirely clear which of these strategies can enable greater improvements on jump height. Thus, the purpose of the meta-analysis was to compare the improvements on countermovement jump (CMJ) performance between training methods which focus on WL exercises, TRT, and PT. Seven studies were included, of which one study performed both comparison. Therefore, four studies comparing WL exercises vs. TRT (total n = 78) and four studies comparing WL exercises vs. PT (total n = 76). The results showed greater improvements on CMJ performance for WL exercises compared to TRT (ESdiff: 0.72 ± 0.23; 95%CI: 0.26, 1.19; P = 0.002; Δ % = 7.5 and 2.1, respectively). The comparison between WL exercises vs. PT revealed no significant difference between protocols (ESdiff: 0.15 ± 0.23; 95%CI: ?0.30, 0.60; P = 0.518; Δ % = 8.8 and 8.1, respectively). In conclusion, WL exercises are superior to promote positive changes on CMJ performance compared to TRT; however, WL exercises and PT are equally effective at improving CMJ performance.  相似文献   
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