76 resultados para Primitive societies
Resumo:
Fonualei is unusual amongst subaerial volcanoes in the Tonga arc because it has erupted dacitic vesicular lavas, tuffs and phreomagmatic deposits for the last 165 years. The total volume of dacite may approach 5 km(3) and overlies basal basaltic andesite and andesite lavas that are constrained to be less than a few millennia in age. All of the products are crystal-poor and formed from relatively low-viscosity magmas inferred to have had temperatures of 1100-1000 degrees C, 2-4 wt % H2O and oxygen fugacities 1-2 log units above the quartz-fayalite-magnetite buffer. Major and trace element data, along with Sr-Nd-Pb and U-Th-Ra isotope data, are used to assess competing models for the origin of the dacites. Positive correlations between Sc and Zr and Sr rule out evolution of the within-dacite compositional array by closed-system crystal fractionation of a single magma batch. An origin by partial melting of lower crustal amphibolites cannot reproduce these data trends or, arguably, any of the dacites either. Instead, we develop a model in which the dacites reflect mixing between two dacitic magmas, each the product of fractional crystallization of basaltic andesite magmas formed by different degrees of partial melting. Mixing was efficient because the two magmas had similar temperatures and viscosities. This is inferred to have occurred at shallow (2-6 km) depths beneath the volcano. U-Th-Ra disequilibria in the basaltic andesite and andesite indicate that the parental magmas had fluids added to their mantle source regions less than 8 kyr ago and that fractionation to the dacitic compositions took less than a few millennia. The 165 year eruption period for the dacites implies that mixing occurred on a similar timescale, possibly during ascent in conduits. The composition of the dacites renders them unsuitable candidates as contributors to average continental crust.
Resumo:
Antiziganism is a widespread phenomenon in all European societies. Poor or rich, ‘postcommunist’ or ‘traditional’, North or South, with ‘lean’ or ‘thick’ welfare systems-all European societies demonstrate antiziganist prejudice.
All across Europe Romanis are among the poorest, most destitute, and most excluded communities. Widespread prejudice and stereotypical representations of Romani individuals limit their chances for participation in democratic decision making processes and their access to services. Unable to counteract majority stereotypes systematically, more often than not they remain on the fringes of society. This edited volume asks where these stereotypes and prejudices come from, why they are ubiquitous to all societies, and how pertinent their impact on antiziganist attitudes found in European societies really is.
Resumo:
Introduction: Chitons (Polyplacophora) are molluscs considered to have a simple nervous system without cephalisation. The position of the class within Mollusca is the topic of extensive debate and neuroanatomical characters can provide new sources of phylogenetic data as well as insights into the fundamental biology of the organisms. We report a new discrete anterior sensory structure in chitons, occurring throughout Lepidopleurida, the order of living chitons that retains plesiomorphic characteristics.
Results: The novel "Schwabe organ" is clearly visible on living animals as a pair of streaks of brown or purplish pigment on the roof of the pallial cavity, lateral to or partly covered by the mouth lappets. We describe the histology and ultrastructure of the anterior nervous system, including the Schwabe organ, in two lepidopleuran chitons using light and electron microscopy. The oesophageal nerve ring is greatly enlarged and displays ganglionic structure, with the neuropil surrounded by neural somata. The Schwabe organ is innervated by the lateral nerve cord, and dense bundles of nerve fibres running through the Schwabe organ epithelium are frequently surrounded by the pigment granules which characterise the organ. Basal cells projecting to the epithelial surface and cells bearing a large number of ciliary structures may be indicative of sensory function. The Schwabe organ is present in all genera within Lepidopleurida (and absent throughout Chitonida) and represents a novel anatomical synapomorphy of the clade.
Conclusions: The Schwabe organ is a pigmented sensory organ, found on the ventral surface of deep-sea and shallow water chitons; although its anatomy is well understood, its function remains unknown. The anterior commissure of the chiton oesophagial nerve ring can be considered a brain. Our thorough review of the chiton central nervous system, and particularly the sensory organs of the pallial cavity, provides a context to interpret neuroanatomical homology and assess this new sense organ.
Resumo:
This chapter explores how to conduct social research in divided and violent societies by developing the concept of the ‘ethical opportunity’. The ‘ethical opportunity’ is situated in a brief discussion of ‘action’ and feminist approaches to research. It argues that seizing the ethical opportunity requires researchers to: plan for their personal safety, plan for participants’ personal safety and plan how they will communicate and disseminate their results. It draws on the author’s personal experience researching in South Africa, Zimbabwe and Northern Ireland, concluding that it is in the communication and dissemination phase that researchers’ hopes for ‘making a difference’ may be realised or dashed. It cautions would-be researchers to manage their own – and research participants’ – expectations about what social research can achieve. Its effects may not often be as transforming and liberating as idealistic researchers hope for, but that should not dissuade them from striving towards those ends.
Resumo:
Diagnosis of glaucoma and delivery of effective treatment is difficult everywhere, but additional challenges are evident in less affluent parts of the world, where the largest numbers of patients with this disease are living. The problems of providing good glaucoma care are examined with especial reference to south-east Asia including China and India and countries in sub-Saharan Africa. The relatively low priority given to glaucoma by vision-related and other nongovernmental organizations (NGOs) due to difficulties faced in delivering effective glaucoma screening and therapeutic interventions are discussed, together with possible future directions for increasing resources and priority for glaucoma care in poor areas.
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During the years of political violence in Northern Ireland many looked to schools to contribute to reconciliation. A variety of interventions were attempted throughout those years, but there was little evidence that any had produced systemic change. The peace process provided an opportunity for renewed efforts. This paper outlines the experience of a series of projects on 'shared education', or the establishment of collaborative networks of Protestant, Catholic and integrated schools in which teachers and pupils moved between schools to take classes and share experiences. The paper outlines the genesis of the idea and the research which helped inform the shape of the shared education project. The paper also outlines the corpus of research which has examined various aspects of shared education practice and lays out the emergent model which is helping to inform current government practice in Northern Ireland, and is being adopted in other jurisdictions. The paper concludes by looking at the prospects for real transformation of education in Northern Ireland.
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The role of Constitutional Courts in deeply divided societies is complicated by the danger that the salient societal cleavages may influence judicial decision-making and, consequently, undermine judicial independence and impartiality. With reference to the decisions of the Constitutional Court of Bosnia-Herzegovina, this article investigates the influence of ethno-nationalism on judicial behaviour and the extent to which variation in judicial tenure amplifies or dampens that influence. Based on a statistical analysis of an original dataset of the Court’s decisions, we find that the judges do in fact divide predictably along ethno-national lines, at least in certain types of cases, and that these divisions cannot be reduced to a residual loyalty to their appointing political parties. Contrary to some theoretical expectations, however, we find that long-term tenure does little to dampen the influence of ethno-nationalism on judicial behaviour. Moreover, our findings suggest that the longer a judge serves on the Court the more ethno-national affiliation seems to influence her decision-making. We conclude by considering how alternative arrangements for the selection and tenure of judges might help to ameliorate this problem.
Resumo:
The targeted destruction of heritage sites in recent conflicts in Syria, Iraq and Mali has tragically illustrated how the treatment of heritage, as the tangible manifestation of the identity of the ‘other’, can be a symptom of the nadir to which group relations can descend. In a world in which the nation-state remains the primary means of identification, the following overarching research question was investigated: How do nation-states narrate their pasts in the built form? Drawing upon the conceptualisation of heritage as a present-orientated and political construct that is utilised to represent the values of the “dominant political, social, religious or ethnic groups” (Graham, Ashworth & Tunbridge 2000: p.183), this paper discusses the role that heritage interventions can play in both emphasising gulfs and building bridges in divided post-conflict societies (Fojut 2009).
Resumo:
The research analyses ‘Northern Irish’ identity narratives post-agreement, and examines the configuration of frame agendas in terms of individual narrative components. A content analysis utilised news published through 1997–2014 within Northern Ireland daily newspapers – the Belfast Telegraph, the Irish News and the News Letter. A process of manifest coding produced an emergent coding scheme displaying the relative stability of media frames surrounding the Northern Irish identity as broadly partisan; however, there is also a subtle narrative shift of Northern Irish identity across the time periods; and findings of a dominant framing paradigm of political and social conceptions of identification post-agreement.