1,749 research outputs found

    Looming struggles over technology for border control

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    New technologies under development, capable of inflicting pain on masses of people, could be used for border control against asylum seekers. Implementation might be rationalized by the threat of mass migration due to climate change, nuclear disaster or exaggerated fears of refugees created by governments. We focus on taser anti-personnel mines, suggesting both technological countermeasures and ways of making the use of such technology politically counterproductive. We also outline several other types of ‘non-lethal’ technology that could be used for border control and raise human rights concerns: high-powered microwaves, armed robots, wireless tasers, acoustic devices/vortex rings, ionizing and pulsed energy lasers, chemical calmatives, convulsants, bioregulators and malodurants. Whether all these possible border technologies will be implemented is a matter for speculation, but their serious human rights implications warrant advance scrutiny

    Children in need: an examination of policy formulation in Scottish social work

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    Implementation of the Children (Scotland) Act 1995 introduced a new service category for children and their families. This new category raised questions regarding its impact on eligibility criteria and responsibility for service provision. This study responded to an identified gap in knowledge regarding the implementation of 'children in need' policy in Scottish Social Work Departments and sought to answer a key question; How is children in need policy formulated by Social Work Services staff on a conceptual and operational level? The research approached this issue from a perspective that policy includes written and verbal discourse as well as practice, including formal and informal organisational policy. Children in need policy is considered within a theoretical analysis of 'need' and an 'Integrated Power Framework'. Both the content and the process of policy formulation were analysed. Staff from three Social Work Departments in Scotland participated in the research. In-depth qualitative interviews, questionnaires and key documents comprised the data sources. Findings showed that major differences between local authorities were not evident. Clear differences were found between managers, supervisors and social workers' workers' definitions and ways of implementing 'children in need' policy. Although most staff were supportive of the principles underlying 'children in need' policy, few other than managers regularly implemented the formal policy. When children in need policy was implemented it was generally used for planning and assessment as well as to advocate for a corporate approach to planning and provision and on behalf of service users for improved services. These findings have implications for entitlement, planning and provision of services for individual and groups of children deemed 'in need'

    Faster Approximate String Matching for Short Patterns

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    We study the classical approximate string matching problem, that is, given strings PP and QQ and an error threshold kk, find all ending positions of substrings of QQ whose edit distance to PP is at most kk. Let PP and QQ have lengths mm and nn, respectively. On a standard unit-cost word RAM with word size w≄log⁥nw \geq \log n we present an algorithm using time O(nk⋅min⁥(log⁥2mlog⁥n,log⁥2mlog⁥ww)+n) O(nk \cdot \min(\frac{\log^2 m}{\log n},\frac{\log^2 m\log w}{w}) + n) When PP is short, namely, m=2o(log⁥n)m = 2^{o(\sqrt{\log n})} or m=2o(w/log⁥w)m = 2^{o(\sqrt{w/\log w})} this improves the previously best known time bounds for the problem. The result is achieved using a novel implementation of the Landau-Vishkin algorithm based on tabulation and word-level parallelism.Comment: To appear in Theory of Computing System

    Viability of primordial black holes as short period gamma-ray bursts

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    It has been proposed that the short period gamma-ray bursts, which occur at a rate of ∌10yr−1\sim 10 {\rm yr^{-1}}, may be evaporating primordial black holes (PBHs). Calculations of the present PBH evaporation rate have traditionally assumed that the PBH mass function varies as MBH−5/2M_{{\rm BH}}^{-5/2}. This mass function only arises if the density perturbations from which the PBHs form have a scale invariant power spectrum. It is now known that for a scale invariant power spectrum, normalised to COBE on large scales, the PBH density is completely negligible, so that this mass function is cosmologically irrelevant. For non-scale-invariant power spectra, if all PBHs which form at given epoch have a fixed mass then the PBH mass function is sharply peaked around that mass, whilst if the PBH mass depends on the size of the density perturbation from which it forms, as is expected when critical phenomena are taken into account, then the PBH mass function will be far broader than MBH−5/2 M_{{\rm BH}}^{-5/2}. In this paper we calculate the present day PBH evaporation rate, using constraints from the diffuse gamma-ray background, for both of these mass functions. If the PBH mass function has significant finite width, as recent numerical simulations suggest, then it is not possible to produce a present day PBH evaporation rate comparable with the observed short period gamma-ray burst rate. This could also have implications for other attempts to detect evaporating PBHs.Comment: 5 pages, 2 figures, version to appear in Phys. Rev. D with additional reference

    Ethiopian volcanic hazards: a changing research landscape

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    Collaborative research projects have a significant role in filling the knowledge gaps that are obstacles to the rigorous assessment of volcanic hazards in some locations. Research is essential to generate the evidence on which raising awareness of volcanic hazards, monitoring and early warning systems, risk reduction activities and efforts to increase resilience can be built. We report the current state of volcanic hazards research and practice in Ethiopia and on the collaborative process used in the Afar Rift Consortium project to promote awareness of volcanic hazards. Effective dissemination of findings to stakeholders and the integration of results into existing practice need leadership by in-country researchers, effective long-term collaboration with other researchers (e.g. international groups) and operational scientists, in addition to integration with existing programmes related to disaster risk reduction initiatives

    Environmental associations of abundance-weighted functional traits in Australian plant communities

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    Predictions of how vegetation responds to spatial and temporal differences in climate rely on established links with plant functional traits and vegetation types that can be encoded into Dynamic Global Vegetation Models. Individual traits have been linked to climate at species level and at community level within regions. However, a recent global assessment of aggregated community level traits found unexpectedly weak links with macroclimate, bringing into question broadscale trait–climate associations and implicating local-scale environmental differences in the filtering of communities. To further evaluate patterns in light of these somewhat contradictory results, we quantified the power of macro-environmental variables to explain aggregated plant community traits, taking advantage of new trait data for leaf area, plant height and seed mass combined with a national survey that records cover-abundance using consistent methods for a large number of plots across Australia. In contrast to the global study, we found that abundance-weighted community mean and variance of leaf area and maximum height were correlated with macroclimate. Height and leaf area were highest in wet (especially warm, wet) environments, with actual evapotranspiration explaining 30% of variation in leaf area and 26% in maximum height. Seed mass was weakly related to environment, with no variable explaining more than 5% of variance. Considering all three traits together in a redundancy analysis, the complete set of environmental variables explained 43% of variation in site-mean traits and 29% of within-site trait variance. While significant trait variation remains unexplained, the trait–environment relationships reported here suggest climatically-driven filtering plays a strong role in assembling these vegetation communities. Regional assessments using standardised species abundances can therefore be used to predict aspects of vegetation function. Our quantification of plant community trait patterns along macroclimatic gradients at continental scale thereby contributes a much-needed functional basis for Australian vegetation.Greg R. Guerin, Rachael V. Gallagher, Ian J. Wright, Samuel C. Andrew, Daniel S. Falster, Elizabeth Wenk, Samantha E.M. Munroe, Andrew J. Lowe, Ben Sparro

    Red Queen Coevolution on Fitness Landscapes

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    Species do not merely evolve, they also coevolve with other organisms. Coevolution is a major force driving interacting species to continuously evolve ex- ploring their fitness landscapes. Coevolution involves the coupling of species fit- ness landscapes, linking species genetic changes with their inter-specific ecological interactions. Here we first introduce the Red Queen hypothesis of evolution com- menting on some theoretical aspects and empirical evidences. As an introduction to the fitness landscape concept, we review key issues on evolution on simple and rugged fitness landscapes. Then we present key modeling examples of coevolution on different fitness landscapes at different scales, from RNA viruses to complex ecosystems and macroevolution.Comment: 40 pages, 12 figures. To appear in "Recent Advances in the Theory and Application of Fitness Landscapes" (H. Richter and A. Engelbrecht, eds.). Springer Series in Emergence, Complexity, and Computation, 201

    The Obliquity of HIP 67522 b: A 17 Myr Old Transiting Hot, Jupiter-sized Planet

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    HIP 67522 b is a 17 Myr old, close-in (P orb = 6.96 days), Jupiter-sized (R = 10 R ⊕) transiting planet orbiting a Sun-like star in the Sco-Cen OB association. We present our measurement of the system's projected orbital obliquity via two spectroscopic transit observations using the CHIRON spectroscopic facility. We present a global model that accounts for large surface brightness features typical of such young stars during spectroscopic transit observations. With a value of | λ | = 5.8-5.7+2.8 it is unlikely that this well-aligned system is the result of a high-eccentricity-driven migration history. By being the youngest planet with a known obliquity, HIP 67522 b holds a special place in contributing to our understanding of giant planet formation and evolution. Our analysis shows the feasibility of such measurements for young and very active stars
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