1,423 research outputs found

    FUNNet:a novel biologically-inspired routing algorithm based on fungi

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    Future data communication networks show three emerging trends: increasing size of networks, increasing traffic volumes and dynamic network topologies. Efficient network management solutions are required that are scalable, can cope with large, and increasing, traffic volumes and provide decentralised and adaptive routing strategies that cope with the dynamics of the network topology. Routing strategies are an important aspect of network management as they have a significant influence on the overall network performance. This paper introduces the preliminary studies for FUNNet, a new routing algorithm inspired by the kingdom of Fungi. Fungi form robust, resilient and responsive networks and these networks change topology as a consequence of changes in local conditions. Fungi are capable of expanding in size as they self-regulate and optimise the balance between exploration and exploitation which is dependent on the transport of the internal resource, i.e. ‘traffic’, within the network. FUNNet exploits the biological processes that are responsible for simulating fungal networks in a bio-inspired routing protocol. The initial results are positive and suggest that fungal metaphors can improve network management, although further evaluation of more complex scenarios is required

    School sport and academic achievement

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    ABSTRACT BACKGROUND: Physical Education and School Sport (PESS) is an integral part of the school curriculum in Ireland. Historically the Healthy Body, Healthy Mind philosophy has promoted the inclusion of PESS alongside more cognitive school subjects and research suggests that PESS can promote cognitive function and provide educational benefits. However there is little research on how the choice of school sport influences academic achievement. This case study aims to investigate how participation in school sport influences the Leaving Certificate points score in an Irish secondary school. In particular, the study will investigate how the particular sport chosen by students participating in school sport during their Leaving Certificate years influences their Leaving Certificate results. METHODS: The study recorded the Leaving Certificate scores and sporting participation from 402 school children graduating from an all-boys secondary school in the Republic of Ireland during the period 2008-2011. Sports participation was assigned one of four categories: Rugby; Rowing; Soccer; No Sport. RESULTS: Participation in a sport during the Leaving Certificate years conferred a 25.4 point benefit to the final Leaving Certificate score. However, participation in Rowing, the only individual sport available in the study, resulted in significantly higher Leaving Certificate scores than Rugby, Soccer and No Sport (p < .05), conferring an additional 73.4 point benefit over the next highest group, Rugby. CONCLUSION: Promoting participation in school sport and providing access to a range of team and individual sports throughout the secondary school years may be a beneficial way to improve students Leaving Certificate results

    Miniature On-Board Angle of Attack Measurement System for Hypersonic Facilities

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    The most prevalent method of establishing model angle of attack (AoA) in hypersonic wind tunnel facilities is using an encoder in the model support system then calculating sting/balance deflections based on balance output. This method has been shown to be less accurate than on-board methods in subsonic and transonic facilities and preliminary indications, as compared to optical methods, show large discrepancies in a hypersonic facility as well. With improvements in Micro-Electro- Mechanical Systems (MEMS) accelerometer technology more accurate onboard AoA measurement systems are now available for the small models usually found in hypersonic research facilities

    Peculiar Hydrogen-deficient Carbon Stars: Strontium-Rich Stars and the s-Process

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    Context: R Coronae Borealis (RCB) variables and their non-variable counterparts, the dustless Hydrogen-Deficient Carbon (dLHdC) stars have been known to exhibit enhanced s-processed material on their surfaces, especially Sr, Y, and Ba. No comprehensive work has been done to explore the s-process in these types of stars, however one particular RCB star, U Aqr, has been under scrutiny for its extraordinary Sr enhancement. Aims: We aim to identify RCB and dLHdC stars that have significantly enhanced Sr abundances, such as U Aqr, and use stellar evolution models to begin to estimate the type of neutron exposure that occurs in a typical HdC star. Methods: We compare the strength of the Sr II 4077 A˚\AA spectral line to Ca II H to identify the new subclass of Sr-rich HdCs. We additionally use the structural and abundance information from existing RCB MESA models to calculate the neutron exposure parameter, τ\tau Results: We identify six stars in the Sr-rich class. Two are RCBs, and four are dLHdCs. We additionally find that the preferred RCB MESA model has a neutron exposure τ\tau ~ 0.1 mb−1^{-1}, which is lower than the estimated τ\tau between 0.15 and 0.6 mb−1^{-1} for the Sr-rich star U Aqr found in the literature. We find trends in the neutron exposure corresponding to He-burning shell temperature, metallicity, and assumed s-processing site. Conclusions: We have found a sub-class of 6 HdCs known as the Sr-rich class, which tend to lie in the halo, outside the typical distribution of RCBs and dLHdCs. We find that dLHdC stars are more likely to be Sr-rich than RCBs, with an occurrence rate of ~13\% for dLHdCs and ~2\% for RCBs. This is one of the first potential spectroscopic differences between RCBs and dLHdCs, along with dLHdCs having stronger surface abundances of 18^{18}O.Comment: 8 pages, submitted to A&

    Modeling R Coronae Borealis Stars: Effects of He-Burning Shell Temperature and Metallicity

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    The R Coronae Borealis (RCB) stars are extremely hydrogen-deficient carbon stars which produce large amounts of dust, causing sudden deep declines in brightness. They are believed to be formed primarily through white dwarf mergers. In this paper, we use MESA to investigate how post-merger objects with a range of initial He-burning shell temperatures from 2.1 - 5.4 *10^8 K with solar and subsolar metallicities evolve into RCB stars. The most successful model of these has subsolar metallicity and an initial temperature near 3 *10^8 K. We find a strong dependence on initial He-burning shell temperature for surface abundances of elements involved in the CNO cycle, as well as differences in effective temperature and radius of RCBs. Elements involved in nucleosynthesis present around 1 dex diminished surface abundances in the 10% solar metallicity models, with the exception of carbon and lithium which are discussed in detail. Models with subsolar metallicities also exhibit longer lifetimes than their solar counterparts. Additionally, we find that convective mixing of the burned material occurs only in the first few years of post-merger evolution, after which the surface abundances are constant during and after the RCB phase, providing evidence for why these stars show a strong enhancement of partial He-burning products.Comment: 13 pages, 12 figures, accepted to MNRAS on August 15, 202

    Intensive adoption as a management strategy for unowned, urban cats: A case study of 25 years of trap–assess–resolve (TAR) in Auckland, New Zealand

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    Globally, unowned urban cats are a major concern because they may suffer from poor welfare and cause problems, including public health risks, nuisances, and urban wildlife predation. While management options are often presented as a choice between culling or trap–neuter–return (TNR), for 25 years, the Lonely Miaow (Inc.) charity in Auckland, New Zealand (hereafter LM), has used a third strategy—intensive adoption or trap–assess–resolve (TAR). As of 2019, of 14,611 unowned cats trapped, 64.2% were adopted, 22.2% were euthanized if unsocialised or in grave ill-health, 5.7% were neutered and returned to the site, and 7.9% had other outcomes, such as being transferred to other shelters. Adoption rates increased over this time, exceeding 80.0% in 2018 and 2019. The cost of processing each cat from capture to adoption rose from NZD 58 in 1999 to NZD 234 by 2017. Approximately 80% of colonies (sites where cats were trapped) were around residential areas. Approximately 22% of cats required veterinary treatment after capture; common ailments included respiratory infections, ringworm, dental problems, and trauma. Consistently, 52% of cats were young kittens (5 years old. TAR avoids euthanasia where possible. Its effectiveness would be enhanced by fewer abandonments of owned cats and kittens, fitting within integrated strategies for the control of unowned cats involving community education. Cat adoptions improve the welfare of cats and, with appropriate husbandry, should alleviate concerns about nuisances, public health, and attacks on wildlife or the cats themselves, essentially benefitting the community and the cats. This case study is relevant to other cities around the world that are seeking to manage unowned cats

    What academics value: a comparative analysis of research into continuing professional development in four English universities

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    This conference presentation explored findings from four research projects, undertaken in different institutions. The projects highlighted the influence of the changing character of academic identities and the complexity of CPD in higher education (HE). Within this, the paper considered how institutions can respond to this knowledge, with particular regard to contemporary influences such as the UK Professional Standards Framework (HEA 2006). Comparing four different evaluative approaches, the paper demonstrated how multi-faceted research approaches can bring different dimensions to a research area. Thus, for example, in one institution interviews, focus groups, and a survey to examine the attitudes, engagement and perceived priorities in relation to CPD were administered. A second institution developed case study methodology with action research, collating data at different levels. Another institution has undertaken evaluative analysis of existing provision, with the fourth institution carrying out qualitative, narrative research engaging academics across faculties and disciplinary areas. Following exploration of these distinctive methodological approaches, the paper compared the respective findings, which provided evidence of contrasting perspectives and values related to CPD. Each of the studies emphasised that very different cultures and practices exist across the spectrum of subject, discipline and institutional cultures within HE. The concept of ‘trust’ emerges as a significant underpinning value-set that drives engagement in professional development. Furthermore, whilst academics value CPD, there are different approaches to what CPD actually means. Given the complexities of context and meaning, the relationship between valuing professional development and perceived engagement in activities (Rothwell and Arnold, 2005) is also considered. This affects strategic approaches, including implementation of the Professional Standards Framework (HEA 2006) and the value placed on it by both individual and institution. A ‘one-size-fits-all’ approach is inappropriate if we are to respond to what academics value across the diversity of HE; flexibility to apply to subjects and individuals at local levels, is needed. Finally, the paper concluded that professional development in HE should rightly be subjected to analysis and debate across academic cultures and institutional contexts

    R Coronae Borealis Star Evolution: Simulating 3D Merger Events to 1D Stellar Evolution Including Large Scale Nucleosynthesis

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    R Coronae Borealis (RCB) stars are rare hydrogen-deficient carbon-rich variable supergiants thought to be the result of dynamically unstable white dwarf mergers. We attempt to model RCBs through all the relevant timescales by simulating a merger event in Octo-tiger, a 3D adaptive mesh refinement (AMR) hydrodynamics code and mapping the post-merger object into MESA, a 1D stellar evolution code. We then post-process the nucleosynthesis on a much larger nuclear reaction network to study the enhancement of s-process elements. We present models that match observations or previous studies in most surface abundances, isotopic ratios, early evolution and lifetimes. We also observe similar mixing behavior as previous modeling attempts which result in the partial He-burning products visible on the surface in observations. However, we do note that our sub-solar models lack any enhancement in s-process elements, which we attribute to a lack of hydrogen in the envelope. We also find that the Oxygen-16/Oxygen-18 isotopic ratio is very sensitive to initial hydrogen abundance and increases outside of the acceptable range with a hydrogen mass fraction greater than 10−410^{-4}.Comment: 18 pages, 17 figures, 1 table. To be published in The Astrophysical Journa

    Behavioural and physiological indicators of anxiety reflect shared and distinct profiles across individuals with neurogenetic syndromes  

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    Anxiety is heightened in individuals with intellectual disability, particularly in those with specific neurogenetic syndromes. Assessment of anxiety for these individuals is hampered by a lack of appropriate measures that cater for communication impairment, differences in presentation, and overlapping features with co-occurring conditions. Here, we adopt a multi-method approach to identify fine-grained behavioural and physiological (via salivary cortisol) responses to anxiety presses in people with fragile X (FXS; n=27; Mage=20.11y; range 6.32-47.04y) and Cornelia de Lange syndromes (CdLS; n=27; Mage=18.42y; range 4.28–41.08y), two neurogenetic groups at high risk for anxiety, compared to neurotypical children (NT; n=21; Mage=5.97y, range 4.34–7.30y). Results indicate that physical avoidance of feared stimuli and proximity seeking to a familiar adult are prominent behavioural indicators of anxiety/stress in FXS and CdLS. Heightened pervasive physiological arousal was identified in these groups via salivary cortisol. An association between autistic characteristics and anxiety was evident in the FXS group but not in the CdLS group pointing to syndrome-specific nuances in the association between anxiety and autism. This study furthers understanding of the behavioural and physiological presentation of anxiety in individuals with intellectual disability and progresses theoretical developments regarding the development and maintenance of anxiety at the intersection of autism
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