346 research outputs found
Floating stones off El Hierro, Canary Islands: xenoliths of pre-island sedimentary origin in the early products of the October 2011 eruption
The eruption that started off the south coast of El Hierro, Canary Islands, in October 2011 has emitted intriguing eruption products found floating in the sea. These specimens appeared as floating volcanic "bombs" that have in the meantime been termed "restingolites" (after the close-by village of La Restinga) and exhibit cores of white and porous pumice-like material. Currently the nature and origin of these "floating stones" is vigorously debated among researchers, with important implications for the interpretation of the hazard potential of the ongoing eruption. The "restingolites" have been proposed to be either (i) juvenile high-silica magma (e.g. rhyolite), (ii) remelted magmatic material (trachyte), (iii) altered volcanic rock, or (iv) reheated hyaloclastites or zeolite from the submarine slopes of El Hierro. Here, we provide evidence that supports yet a different conclusion. We have collected and analysed the structure and composition of samples and compared the results to previous work on similar rocks found in the archipelago. Based on their high silica content, the lack of igneous trace element signatures, and the presence of remnant quartz crystals, jasper fragments and carbonate relicts, we conclude that "restingolites" are in fact xenoliths from pre-island sedimentary rocks that were picked up and heated by the ascending magma causing them to partially melt and vesiculate. They hence represent messengers from depth that help us to understand the interaction between ascending magma and crustal lithologies in the Canary Islands as well as in similar Atlantic islands that rest on sediment/covered ocean crust (e.g. Cape Verdes, Azores). The occurrence of these "restingolites" does therefore not indicate the presence of an explosive high-silica magma that is involved in the ongoing eruption
More than sense of place? Exploring the emotional dimension of rural tourism experiences
It is widely suggested that participation in rural tourism is underpinned by a sense of rural place or “rurality”. However, although nature and the countryside have long been recognised as a source of spiritual or emotional fulfilment, few have explored the extent to which tourism, itself often claimed to be a sacred experience, offers an emotional/spiritual dimension in the rural context. This paper addresses that literature gap. Using in-depth interviews with rural tourists in the English Lake District, it explores the extent to which, within respondents’ individual understanding of spirituality, a relationship exists between sense of place and deeper, emotional experiences and, especially, whether participation in rural tourism may induce spiritual or emotional responses. The research revealed that all respondents felt a strong attachment to the Lake District; similarly, and irrespective of their openness to spirituality, engaging in rural tourism activities resulted in highly emotive experiences for all respondents, the description/interpretation of such experiences being determined by individual “beliefs”. However, sense of place was not a prerequisite to emotional or spiritual experiences. Being in and engaging with the landscape � effectively becoming part of it � especially through physical activity is fundamental to emotional responses
Effect of Bio-Oss® Collagen and Collagen Matrix on Bone Formation
Objective: to compare the amount of new bone produced by Bio-Oss ® Collagen to that produced by collagen matrix in vivo. Method: eighteen bone defects, 5mm by 10mm were created in the parietal bone of 9 New Zealand White rabbits. 6 defects were grafted with Bio-Oss ® Collagen. 6 defects were grafted with collagen matrix alone (positive control) and 6 were left empty (negative control). Animals were killed on day 14 and the defects were dissected and prepared for histological assessment. Quantitative analysis of new bone formation was made on 100 sections (50 sections for each group) using image analysis. Results: A total of 339% more new bone was present in defects grafted with Bio-Oss ® Collagen than those grafted with collagen matrix (positive control). No bone was formed in the negative control group. Conclusion: Bio-Oss ® Collagen has the effect of stimulating new bone formation locally compared with collagen matrix in vivo. Bio-Oss ® Collagen may be utilized as a bone graft material. © Wong and Rabie; Licensee Bentham Open.published_or_final_versio
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Mitigation of Moral Hazard and Adverse Selection in Venture Capital Financing: The Influence of the Country’s Institutional Setting
A venture capitalist (VC) needs to trade off benefits and costs when attempting to mitigate agency problems in their investor-investee relationship. We argue that signals of ventures complement the VC’s capacity to screen and conduct a due diligence during the pre-investment phase, but its attractiveness may diminish in institutional settings supporting greater transparency. Similarly, whereas a VC may opt for contractual covenants to curb potential opportunism by ventures in the post-investment phase, this may only be effective in settings supportive of shareholder rights enforcement. Using an international sample of VC contracts, our study finds broad support for these conjectures. It delineates theoretical and practical implications for how investors can best deploy their capital in different institutional settings whilst nurturing their relationships with entrepreneurs
RadioActive101-Learning through radio, learning for life: an international approach to the inclusion and non-formal learning of socially excluded young people
This article describes an original international approach to inclusion and non-formal learning of socially excluded young people, through participatory internet radio - RadioActive101. First, we critically discuss the social and digital exclusion of young people. We then describe our approach - that includes partic-ipatory action research methods that are influenced by the work of Dewey and Freire, and operate as a process of complex intervention. This supports the inclusive co-production of radio content in ways that support non-formal learning in two EU contexts – the UK and Portugal. We then summarise and compare a qualitative investigation of RadioActive101. This showed positive results, with important similarities and differences between the two contexts. Participants reported that RadioActive101 was motivating and contributed to the development of contemporary skills, and also stimulated improvements in psychosocial dimensions such as confidence (self-efficacy) and self-esteem. This investigation informed the development of an original recog-nition system for non-formal learning that maps EU Key Competences for Lifelong Learning to radio practic-es and activities that are recognised through electronic badges. Our final reflections emphasise that in order to support the non-formal learning of socially excluded young people we must foreground our attention to foster-ing psychosocial dimensions alongside developing contemporary competences
Complex circular subsidence structures in tephra deposited on large blocks of ice: Varða tuff cone, Öræfajökull, Iceland
Several broadly circular structures up to 16 m in diameter, into which higher strata have sagged and locally collapsed, are present in a tephra outcrop on southwest Öræfajökull, southern Iceland. The tephra was sourced in a nearby basaltic tuff cone at Varða. The structures have not previously been described in tuff cones, and they probably formed by the melting out of large buried blocks of ice emplaced during a preceding jökulhlaup that may have been triggered by a subglacial eruption within the Öræfajökull ice cap. They are named ice-melt subsidence structures, and they are analogous to kettle holes that are commonly found in proglacial sandurs and some lahars sourced in ice-clad volcanoes. The internal structure is better exposed in the Varða examples because of an absence of fluvial infilling and reworking, and erosion of the outcrop to reveal the deeper geometry. The ice-melt subsidence structures at Varða are a proxy for buried ice. They are the only known evidence for a subglacial eruption and associated jökulhlaup that created the ice blocks. The recognition of such structures elsewhere will be useful in reconstructing more complete regional volcanic histories as well as for identifying ice-proximal settings during palaeoenvironmental investigations
The Effects of Sex-Role Attitudes and Group Composition on Men and Women in Groups
The dual impact of group gender composition and sex-role attitudes on self-perceptions and social behavior was explored. Androgynous and stereotyped men and women were placed in groups of skewed sex composition. Subjects\u27 self-descriptions of masculine attributes shifted significantly in the group environment. In some instances, sex role-stereotyped subjects responded most stereotypically when their gender was in the minority in the group. Differences between men and women and between androgynous and stereotyped subjects in sex role-related preferences for group roles and discussion topics were also found
Morris dancers, matriarchs and paperbacks:Doing the village in contemporary Britain
To call a place rural is to categorize it as a particular kind of place and, often, to presume that particular kinds of being innately occur there. Over the past 20 years, however, trends in British rural studies have problematized easy ascription; this article is an ethnographic contribution within those trends. If it is no longer adequate to read the rural as a container for being, then, as I contend here, rurality can be explored anew through doing. I draw upon David Matless’s (1994) frame of ‘doing the village’ representationally, and amplify it to include concepts of place as representational and relational. I thus use ‘doing’ to read the multiple ways in which diverse residents in a Northern England village engage with both their real locality and with nationally shared rural imaginings
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