10,498 research outputs found

    The limits of mean-field heterozygosity estimates under spatial extension in simulated plant populations

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    Computational models of evolutionary processes are increasingly required to incorporate multiple and diverse sources of data. A popular feature to include in population genetics models is spatial extension, which reflects more accurately natural populations than does a mean field approach. However, such models necessarily violate the mean field assumptions of classical population genetics, as do natural populations in the real world. Recently, it has been questioned whether classical approaches are truly applicable to the real world. Individual based models (IBM) are a powerful and versatile approach to achieve integration in models. In this study an IBM was used to examine how populations of plants deviate from classical expectations under spatial extension. Populations of plants that used three different mating strategies were placed in a range of arena sizes giving crowded to sparse occupation densities. Using a measure of population density, the pollen communication distance (Pcd), the deviation exhibited by outbreeding populations differed from classical mean field expectations by less than 5% when Pcd was less than 1, and over this threshold value the deviation significantly increased. Populations with an intermediate mating strategy did not have such a threshold and deviated directly with increasing isolation between individuals. Populations with a selfing strategy were influenced more by the mating strategy than by increased isolation. In all cases pollen dispersal was more influential than seed dispersal. The IBM model showed that mean field calculations can be reasonably applied to natural outbreeding plant populations that occur at a density in which individuals are less than the average pollen dispersal distance from their neighbors

    If you build it, will they come? How researchers perceive and use web 2.0

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    Over the past 15 years, the web has transformed the way we seek and use information. In the last 5 years in particular a set of innovative techniques – collectively termed ‘web 2.0’ – have enabled people to become producers as well as consumers of information. It has been suggested that these relatively easy-to-use tools, and the behaviours which underpin their use, have enormous potential for scholarly researchers, enabling them to communicate their research and its findings more rapidly, broadly and effectively than ever before. This report is based on a study commissioned by the Research Information Network to investigate whether such aspirations are being realised. It seeks to improve our currently limited understanding of whether, and if so how, researchers are making use of various web 2.0 tools in the course of their work, the factors that encourage or inhibit adoption, and researchers’ attitudes towards web 2.0 and other forms of communication. Context: How researchers communicate their work and their findings varies in different subjects or disciplines, and in different institutional settings. Such differences have a strong influence on how researchers approach the adoption – or not – of new information and communications technologies. It is also important to stress that ‘web 2.0’ encompasses a wide range of interactions between technologies and social practices which allow web users to generate, repurpose and share content with each other. We focus in this study on a range of generic tools – wikis, blogs and some social networking systems – as well as those designed specifically by and for people within the scholarly community. Method: Our study was designed not only to capture current attitudes and patterns of adoption but also to identify researchers’ needs and aspirations, and problems that they encounter. We began with an online survey, which collected information about researchers’ information gathering and dissemination habits and their attitudes towards web 2.0. This was followed by in-depth, semi-structured interviews with a stratified sample of survey respondents to explore in more depth their experience of web 2.0, including perceived barriers as well as drivers to adoption. Finally, we undertook five case studies of web 2.0 services to investigate their development and adoption across different communities and business models. Key findings: Our study indicates that a majority of researchers are making at least occasional use of one or more web 2.0 tools or services for purposes related to their research: for communicating their work; for developing and sustaining networks and collaborations; or for finding out about what others are doing. But frequent or intensive use is rare, and some researchers regard blogs, wikis and other novel forms of communication as a waste of time or even dangerous. In deciding if they will make web 2.0 tools and services part of their everyday practice, the key questions for researchers are the benefits they may secure from doing so, and how it fits with their use of established services. Researchers who use web 2.0 tools and services do not see them as comparable to or substitutes for other channels and means of communication, but as having their own distinctive role for specific purposes and at particular stages of research. And frequent use of one kind of tool does not imply frequent use of others as well

    Innovation and Reduction in Contemporary Qualitative Methods: The Case of Conceptual Coupling, Activity-Type Pairs and Auto-Ethnography

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    During the course of this paper we mobilise an ideal typical framework that identifies three waves of reduction within contemporary qualitative inquiry as they relate to key aspects of the sociological tradition. The paper begins with a consideration of one of sociology\'s key questions; namely how is social organisation possible? The paper aims to demonstrate how this question moves from view as increased specialisation and differentiation in qualitative methodology within sociology and related disciplines results in a fragmentation and decontextualisation of social practices from social orders. Indeed, the extent to which qualitative methods have been detached from sociological principles is considered in relation to the emergence of a reductionist tendency. The paper argues that the first wave is typified by conceptual couplings such as \'discourse and the subject\', \'narrative and experience\', \'space and place\' and the second by \'activity type couplings\' such as \'walking and talking\' and \'making and telling\' and then, finally, the third wave exemplified through auto-ethnography and digital lifelogging. We argue each of these three waves represent a series of steps in qualitative reduction that, whilst representing innovation, need to reconnect with questions of action, order and social organisation as a complex whole as opposed to disparate parts.Social Order, Discourse, Narrative, Mobile Methods, Auto-Ethnography, Reflexivity, Innovation, Qualitative Methods

    Embedding calculus knot invariants are of finite type

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    We show that the map on components from the space of classical long knots to the n-th stage of its Goodwillie-Weiss embedding calculus tower is a map of monoids whose target is an abelian group and which is invariant under clasper surgery. We deduce that this map on components is a finite type-(n-1) knot invariant. We also compute the second page in total degree zero for the spectral sequence converging to the components of this tower as Z-modules of primitive chord diagrams, providing evidence for the conjecture that the tower is a universal finite-type invariant over the integers. Key to these results is the development of a group structure on the tower compatible with connect-sum of knots, which in contrast with the corresponding results for the (weaker) homology tower requires novel techniques involving operad actions, evaluation maps, and cosimplicial and subcubical diagrams.Comment: Revised maps to the infinitesimal mapping space model in Sections 3 and 4 and analysis of cubical diagrams in Section 5. Minor expository and organizational changes throughout. Now 28 pages, 4 figure

    Woolworths and Wales: A Multi-Dimensional Analysis of the Loss of a Local Brand

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    In this paper we present a multi-dimensional analysis of the closure of Woolworths in Wales and the way in which the loss of this familiar high-street brand can be accounted for at a number of levels and within different social arenas. Primarily, the paper demonstrates how Woolworths is positioned as a symbol a previous era of consumption centred upon community and place based notions of nostalgia and community. What is striking in the analysis is the similarities in the way in which Woolworths is mobilised as a symbol by the general public and elites; albeit with varying outcomes and affects. In presenting the analysis the paper demonstrates a processual framing as providing a fruitful approach to the combination of different approaches and fields of inquiry (sociology, geography, and political science) without diminishing their distinct contributions.Recession, 'Credit Crunch', Community, Economy, the High-Street, Welsh Assembly Government, Woolworths, Consumption

    Res Judicata: Should California Abandon Primary Rights

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    In but not of, of but not in: On Taste, Hipness, and White Embodiment

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    The status of the body figures paradoxically in the interrelated discourses of whiteness, aesthetic taste, and hipness. While Richard Dyer’s analysis of whiteness argues that white identity is “in but not of the body,” Carolyn Korsmeyer’s and Julia Kristeva’s feminist analyses of aesthetic “taste” demonstrate that this faculty is traditionally conceived as something “of” but not “in” the body. While taste directly distances whiteness from embodiment, hipness negatively affirms this same distance: the hipster proves his elite status within white culture by positioning himself as, in the words of James Chance’s song title, “Almost Black.” The notion of hip contributes to my analysis of taste by focusing on both the gender politics of white embodiment, and how, by taking the social body as object of the prepositions “in” and “of,” these discourses of taste and hipness produce individual bodies as white, and maintain Whiteness as a socio-political norm
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