207 research outputs found

    Linking tourism, retirement migration and social capital

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    A general trend in the study of international retirement migration has been the increased attention paid to the social contacts and network connections of the migrants in both the destination and the origin areas. These studies have examined the extent to which migrants build social relationships with their neighbours and the host society while also maintaining social links with their countries of origin, addressing the central role that leisure travel plays in sustaining increasingly dispersed social networks and maintaining the social capital of these networks and of the individuals involved in them. Using a case study approach to examine British retirement migration to Spain, we explore the relevance of transnational social networks in the context of international retirement migration, particularly the intensity of bidirectional visiting friends and relatives (VFR) tourism flows and the migrants' social contacts with friends and/or family back in their home country. Building on the concept of social capital and Putnam's distinction between bonding and bridging social capital, we propose a framework for the analysis of the migrants' international social networks. The results of a study conducted based on a sample of 365 British retirees living in the coast of Alicante (Spain) show both the strength of the retirees' international bonding social capital and the role of 'VFR's travel and communication technologies in sustaining the migrants' transnational social practices and, ultimately, their international bonding social capital. It also provides evidence for the reinforcing links between tourism-related mobility and amenity-seeking migration in later life. © 2013 © 2013 Taylor & Francis

    Energy efficiency in friction-based locomotion mechanisms for soft and hard robots: slower can be faster

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    Many recent designs of soft robots and nano-robots feature locomotion mechanisms that cleverly exploit slipping and sticking phenomena. These mechanisms have many features in common with peristaltic locomotion found in the animal world. The purpose of the present paper is to examine the energy efficiency of a locomotion mechanism that exploits friction. With the help of a model that captures most of the salient features of locomotion, we show how locomotion featuring stick-slip friction is more efficient than a counterpart that only features slipping. Our analysis also provides a framework to establish how optimal locomotion mechanisms can be selected

    Symbolic meanings and e-learning in the workplace: The case of an intranet-based training tool

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    This article contributes to the debate on work-based e-learning, by unpacking the notion of ‘the learning context’ in a case where the mediating tool for training also supports everyday work. Users’ engagement with the information and communication technology tool is shown to reflect dynamic interactions among the individual, peer group, organizational and institutional levels. Also influential are professionals’ values and identity work, alongside their interpretations of espoused and emerging symbolic meanings. Discussion draws on pedagogically informed studies of e-learning and the wider organizational learning literature. More centrally, this article highlights the instrumentality of symbolic interactionism for e-learning research and explores some of the framework’s conceptual resources as applied to organizational analysis and e-learning design. </jats:p

    On the development of rod-based models for pneumatically actuated soft robot arms: A five-parameter constitutive relation

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    While soft robots have many attractive features compared to their hard counterparts, developing tractable models for these highly deformable, nonlinear, systems is challenging. In a recent paper, the authors published a non-classic, five-parameter constitutive relation for a rod-based model of a widely used, pneumatically actuated soft robot arm. It is natural to ask if the complexity of the relation can be eliminated by redesigning the actuator? To this end, finite element models and experimental results are used to further explore the five-parameter constitutive relation. For multiple designs of the pneumatically actuated soft robot arm, we are able to demonstrate how finite element models can be employed in place of experiments to specify the constitutive relations and how the relations are scalable by actuator length and applied pressure. Our primary result is the finding that the five-parameter constitutive relation is germane to pneumatically actuated soft robot arms and the parameters for this relation can be determined by three finite element simulations

    Effects of attention and perceptual uncertainty on cerebellar activity during visual motion perception

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    Recent clinical and neuroimaging studies have revealed that the human cerebellum plays a role in visual motion perception, but the nature of its contribution to this function is not understood. Some reports suggest that the cerebellum might facilitate motion perception by aiding attentive tracking of visual objects. Others have identified a particular role for the cerebellum in discriminating motion signals in perceptually uncertain conditions. Here, we used functional magnetic resonance imaging to determine the degree to which cerebellar involvement in visual motion perception can be explained by a role in sustained attentive tracking of moving stimuli in contrast to a role in visual motion discrimination. While holding the visual displays constant, we manipulated attention by having participants attend covertly to a field of random-dot motion or a colored spot at fixation. Perceptual uncertainty was manipulated by varying the percentage of signal dots contained within the random-dot arrays. We found that attention to motion under high perceptual uncertainty was associated with strong activity in left cerebellar lobules VI and VII. By contrast, attending to motion under low perceptual uncertainty did not cause differential activation in the cerebellum. We found no evidence to support the suggestion that the cerebellum is involved in simple attentive tracking of salient moving objects. Instead, our results indicate that specific subregions of the cerebellum are involved in facilitating the detection and discrimination of task-relevant moving objects under conditions of high perceptual uncertainty. We conclude that the cerebellum aids motion perception under conditions of high perceptual demand

    Commercial chicken breeds exhibit highly divergent patterns of linkage disequilibrium

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    The analysis of linkage disequilibrium (LD) underpins the development of effective genotyping technologies, trait mapping and understanding of biological mechanisms such as those driving recombination and the impact of selection. We apply the Malécot-Morton model of LD to create additive LD maps that describe the high-resolution LD landscape of commercial chickens. We investigated LD in chickens (Gallus gallus) at the highest resolution to date for broiler, white egg and brown egg layer commercial lines. There is minimal concordance between breeds of fine-scale LD patterns (correlation coefficient &lt;0.21), and even between discrete broiler lines. Regions of LD breakdown, which may align with recombination hot spots, are enriched near CpG islands and transcription start sites (P&lt;2.2 × 10?16), consistent with recent evidence described in finches, but concordance in hot spot locations between commercial breeds is only marginally greater than random. As in other birds, functional elements in the chicken genome are associated with recombination but, unlike evidence from other bird species, the LD landscape is not stable in the populations studied. The development of optimal genotyping panels for genome-led selection programmes will depend on careful analysis of the LD structure of each line of interest. Further study is required to fully elucidate the mechanisms underlying highly divergent LD patterns found in commercial chickens

    Tumour vascularization: sprouting angiogenesis and beyond

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    Tumour angiogenesis is a fast growing domain in tumour biology. Many growth factors and mechanisms have been unravelled. For almost 30 years, the sprouting of new vessels out of existing ones was considered as an exclusive way of tumour vascularisation. However, over the last years several additional mechanisms have been identified. With the discovery of the contribution of intussusceptive angiogenesis, recruitment of endothelial progenitor cells, vessel co-option, vasculogenic mimicry and lymphangiogenesis to tumour growth, anti-tumour targeting strategies will be more complex than initially thought. This review highlights these processes and intervention as a potential application in cancer therapy. It is concluded that future anti-vascular therapies might be most beneficial when based on multimodal anti-angiogenic, anti-vasculogenic mimicry and anti-lymphangiogenic strategies

    Keep them alive! Design and Evaluation of the “Community Fostering Reference Model”

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    Firms host online communities for commercial purposes, for example in order to integrate customers into ideation for new product development. The success of these firm-hosted online communities depends entirely on the cooperation of a high number of customers that constantly produce valuable knowledge for firms. However, in practice, the majority of successfully implemented communities suffers from stagnation and even a decrease of member activities over time. Literature provides numerous guidelines on how to build and launch these online communities. While these models describe the initial steps of acquiring and activating a community base from scratch very well and explicitly, they neglect continuous member activation and acquistion after a successful launch. Against this background, the authors propose the Community Fostering Reference Model (CoFoRM), which represents a set of general procedures and instruments to continuously foster member activity. In this paper, the authors present the theory-driven design as well as the evaluation of the CoFoRM in a practical use setting. The evaluation results reveal that the CoFoRM represents a valuable instrument in the daily working routine of community managers, since it efficiently helps activating community members especially in the late phases of a community’s LifeCycle
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