5,562 research outputs found

    A Database for Fast Access to Particle-Gated Event Data

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    In nuclear physics experiments involving in-flight fragmentation of ions, usually a large number of different nuclei is produced and various detection systems are employed to identify the species event by event, e.g. by measuring their specific energy loss and time-of-flight. For such cases -- not necessarily limited to nuclear physics -- where subsets of a large dataset can be identified using a small number of measured signals a software for fast access to varying subsets of such a dataset has been developed. The software has been used successfully in the analysis of a one neutron knock-out experiment at GANIL

    The consequences of gene flow for local adaptation and differentiation: A two-locus two-deme model

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    We consider a population subdivided into two demes connected by migration in which selection acts in opposite direction. We explore the effects of recombination and migration on the maintenance of multilocus polymorphism, on local adaptation, and on differentiation by employing a deterministic model with genic selection on two linked diallelic loci (i.e., no dominance or epistasis). For the following cases, we characterize explicitly the possible equilibrium configurations: weak, strong, highly asymmetric, and super-symmetric migration, no or weak recombination, and independent or strongly recombining loci. For independent loci (linkage equilibrium) and for completely linked loci, we derive the possible bifurcation patterns as functions of the total migration rate, assuming all other parameters are fixed but arbitrary. For these and other cases, we determine analytically the maximum migration rate below which a stable fully polymorphic equilibrium exists. In this case, differentiation and local adaptation are maintained. Their degree is quantified by a new multilocus version of \Fst and by the migration load, respectively. In addition, we investigate the invasion conditions of locally beneficial mutants and show that linkage to a locus that is already in migration-selection balance facilitates invasion. Hence, loci of much smaller effect can invade than predicted by one-locus theory if linkage is sufficiently tight. We study how this minimum amount of linkage admitting invasion depends on the migration pattern. This suggests the emergence of clusters of locally beneficial mutations, which may form `genomic islands of divergence'. Finally, the influence of linkage and two-way migration on the effective migration rate at a linked neutral locus is explored. Numerical work complements our analytical results

    Individual homogenization in large-scale systems: on the politics of computer and social architectures

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    One determining characteristic of contemporary sociopolitical systems is their power over increasingly large and diverse populations. This raises questions about power relations between heterogeneous individuals and increasingly dominant and homogenizing system objectives. This article crosses epistemic boundaries by integrating computer engineering and a historicalphilosophical approach making the general organization of individuals within large-scale systems and corresponding individual homogenization intelligible. From a versatile archeological-genealogical perspective, an analysis of computer and social architectures is conducted that reinterprets Foucault’s disciplines and political anatomy to establish the notion of politics for a purely technical system. This permits an understanding of system organization as modern technology with application to technical and social systems alike. Connecting to Heidegger’s notions of the enframing (Gestell) and a more primal truth (anfänglicheren Wahrheit), the recognition of politics in differently developing systems then challenges the immutability of contemporary organization. Following this critique of modernity and within the conceptualization of system organization, Derrida’s democracy to come (à venir) is then reformulated more abstractly as organizations to come. Through the integration of the discussed concepts, the framework of Large-Scale Systems Composed of Homogeneous Individuals (LSSCHI) is proposed, problematizing the relationships between individuals, structure, activity, and power within large-scale systems. The LSSCHI framework highlights the conflict of homogenizing system-level objectives and individual heterogeneity, and outlines power relations and mechanisms of control shared across different social and technical systems

    Extinction risk by mutational meltdown

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    The Regional Dimension of Sectoral Innovativeness An Empirical Investigation of Two Specialised Supplier and Two Science-Based Industries

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    The aim of this paper is to test how geographical and technological proximity relate to a particular industry's innovative output. Two mechanisms are therefore tested, i.e. agglomeration economies and the regional exploitation of technological proximity. A new dataset is applied, which includes German patent applications from within the period 1995 to 2006. Four industries are considered, two of which are science-based, whereas the remaining two are specialised supplier industries. While diversity is associated with high innovative output in the specialised supplier industries, the results for specialisation are mixed. However, all industries seem to benefit, at least to a certain degree, from the regional re-combination of their own technologies with those of specific key industries.Innovation, Proximity, Diversity
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