5,545 research outputs found

    The secret life of water systems: least cost planning beyond demand management

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    The water industry in Australia and international is involved in a period of significant change. The conventional roles of water and wastewater utilities are being redefined with the objectives of resource conservation and sustainable development added to existing responsibilities. Least cost planning (LCP) has emerged as the way forward for water utilities in regions where water conservation has become an objective or where ongoing supply expansion is constrained. It involves techniques for the design and evaluation of demand management programs and aims to compare demand- and supply-side options on an equivalent basis. The approach is based on the key ideas that: demand is for the services water provides rather than the actual volume supplied; and that a drop of water saved is equal to a drop supplied. This paper contends that LCP has much to offer the water sector beyond demand management. It is an approach that has potential for options assessment across the water cycle and can aid planning towards more sustainable outcomes within the sector. The paper concludes that LCP concepts and techniques will have worth in addressing the challenges of sustainable development for both urban water systems and catchment managemen

    More positive group memberships are associated with greater resilience in Royal Air Force (RAF) personnel

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    © 2020 The Authors. British Journal of Social Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society In the current project, we examined how perceived group memberships (number, and characteristics, of), social and relational identification, and social identity leadership are associated with resilience in Royal Air Force (RAF) personnel. Based on social identity theorizing, we hypothesized positive associations between the number of groups, perceptions of their characteristics (e.g., positivity), and how they relate to each other (i.e., compatibility) and resilience (H1). We also hypothesized positive associations between both social identity leadership (H2) and resilience, and social and relational identification (H3) and resilience. Two hundred and forty-three personnel from 18 RAF bases completed an identity mapping exercise and measures of leadership, social and relational identification, and resilience. Our findings highlighted the importance of the association between positive group memberships and resilience, and social identification and resilience. Counter to our hypothesis, belonging to more groups was negatively associated with resilience, and there were non-significant relationships between three principles of social identity leadership and resilience, with embedding identity being significantly negatively associated with resilience. In support of social identity theorizing, the number of positive groups was positively associated with resilience, as was social identification. These findings indicate that, for RAF personnel, it is belonging to positive groups, both within and outside work, along with social identification, that is positively associated with resilience

    Characterising the phenotypic diversity of Papilio dardanus wing patterns using an extensive museum collection

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    The history of 20th Century evolutionary biology can be followed through the study of mimetic butterflies. From the initial findings of discontinuous polymorphism through the debates regarding the evolution of mimicry and the step-size of evolutionary change, to the studies on supergene evolution and molecular characterisation of butterfly genomes, mimetic butterflies have been at the heart of evolutionary thought for over 100 years. During this time, few species have received as much attention and in-depth study as Papilio dardanus. To assist all aspects of mimicry research, we present a complete data-derived overview of the extent of polymorphism within this species. Using historical samples permanently held by the NHM London, we document the extent of phenotypic variation and characterise the diversity present in each of the subspecies and how it varies across Africa. We also demonstrate an association between “imperfect” mimetic forms and the transitional race formed in the area where Eastern and Western African populations meet around Lake Victoria. We present a novel portal for access to this collection, www.mimeticbutterflies.org, allowing remote access to this unique repository. It is hoped that this online resource can act as a nucleus for the sharing and dissemination of other collections databases and imagery connected with mimetic butterflies

    An extragalactic supernebula confined by gravity

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    Little is known about the origins of the giant star clusters known as globular clusters. How can hundreds of thousands of stars form simultaneously in a volume only a few light years across the distance of the sun to its nearest neighbor? Radiation pressure and winds from luminous young stars should disperse the star-forming gas and disrupt the formation of the cluster. Globular clusters in our Galaxy cannot provide answers; they are billions of years old. Here we report the measurement of infrared hydrogen recombination lines from a young, forming super star cluster in the dwarf galaxy, NGC 5253. The lines arise in gas heated by a cluster of an estimated million stars, so young that it is still enshrouded in gas and dust, hidden from optical view. We verify that the cluster contains 4000-6000 massive, hot "O" stars. Our discovery that the gases within the cluster are bound by gravity may explain why these windy and luminous O stars have not yet blown away the gases to allow the cluster to emerge from its birth cocoon. Young clusters in "starbursting" galaxies in the local and distant universe may be similarly gravitationally confined and cloaked from view.Comment: Letter to Natur

    Reproducible kk-means clustering in galaxy feature data from the GAMA survey

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    A fundamental bimodality of galaxies in the local Universe is apparent in many of the features used to describe them. Multiple sub-populations exist within this framework, each representing galaxies following distinct evolutionary pathways. Accurately identifying and characterising these sub-populations requires that a large number of galaxy features be analysed simultaneously. Future galaxy surveys such as LSST and Euclid will yield data volumes for which traditional approaches to galaxy classification will become unfeasible. To address this, we apply a robust kk-means unsupervised clustering method to feature data derived from a sample of 7338 local-Universe galaxies selected from the Galaxy And Mass Assembly (GAMA) survey. This allows us to partition our sample into kk clusters without the need for training on pre-labelled data, facilitating a full census of our high dimensionality feature space and guarding against stochastic effects. We find that the local galaxy population natively splits into 22, 33, 55 and a maximum of 66 sub-populations, with each corresponding to a distinct ongoing evolutionary mechanism. Notably, the impact of the local environment appears strongly linked with the evolution of low-mass (M<1010M_{*} < 10^{10} M_{\odot}) galaxies, with more massive systems appearing to evolve more passively from the blue cloud onto the red sequence. With a typical run time of 3\sim3 minutes per value of kk for our galaxy sample, we show how kk-means unsupervised clustering is an ideal tool for future analysis of large extragalactic datasets, being scalable, adaptable, and providing crucial insight into the fundamental properties of the local galaxy population

    Cognitive behavioural therapy as an adjunct to pharmacotherapy for primary care based patients with treatment resistant depression: Results of the CoBalT randomised controlled trial

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    Copyright © 2013 Elsevier. NOTICE: This is the author’s version of a work accepted for publication by Elsevier. Changes resulting from the publishing process, including peer review, editing, corrections, structural formatting and other quality control mechanisms, may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in The Lancet, 2013, Vol. 381, Issue 9864, pp. 375 - 384 DOI: http://dx.doi.org/10.1016/S0140-6736(12)61552-9BACKGROUND: Only a third of patients with depression respond fully to antidepressant medication but little evidence exists regarding the best next-step treatment for those whose symptoms are treatment resistant. The CoBalT trial aimed to examine the effectiveness of cognitive behavioural therapy (CBT) as an adjunct to usual care (including pharmacotherapy) for primary care patients with treatment resistant depression compared with usual care alone. METHODS: This two parallel-group multicentre randomised controlled trial recruited 469 patients aged 18-75 years with treatment resistant depression (on antidepressants for ≥6 weeks, Beck depression inventory [BDI] score ≥14 and international classification of diseases [ICD]-10 criteria for depression) from 73 UK general practices. Participants were randomised, with a computer generated code (stratified by centre and minimised according to baseline BDI score, whether the general practice had a counsellor, previous treatment with antidepressants, and duration of present episode of depression) to one of two groups: usual care or CBT in addition to usual care, and were followed up for 12 months. Because of the nature of the intervention it was not possible to mask participants, general practitioners, CBT therapists, or researchers to the treatment allocation. Analyses were by intention to treat. The primary outcome was response, defined as at least 50% reduction in depressive symptoms (BDI score) at 6 months compared with baseline. This trial is registered, ISRCTN38231611. FINDINGS: Between Nov 4, 2008, and Sept 30, 2010, we assigned 235 patients to usual care, and 234 to CBT plus usual care. 422 participants (90%) were followed up at 6 months and 396 (84%) at 12 months, finishing on Oct 31, 2011. 95 participants (46%) in the intervention group met criteria for response at 6 months compared with 46 (22%) in the usual care group (odds ratio 3·26, 95% CI 2·10-5·06, p<0·001). INTERPRETATION: Before this study, no evidence from large-scale randomised controlled trials was available for the effectiveness of augmentation of antidepressant medication with CBT as a next-step for patients whose depression has not responded to pharmacotherapy. Our study has provided robust evidence that CBT as an adjunct to usual care that includes antidepressants is an effective treatment, reducing depressive symptoms in this population.National Institute for Health Research Health Technology Assessment

    Characterization of extrasolar terrestrial planets from diurnal photometric variability

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    The detection of massive planets orbiting nearby stars has become almost routine, but current techniques are as yet unable to detect terrestrial planets with masses comparable to the Earth's. Future space-based observatories to detect Earth-like planets are being planned. Terrestrial planets orbiting in the habitable zones of stars-where planetary surface conditions are compatible with the presence of liquid water-are of enormous interest because they might have global environments similar to Earth's and even harbor life. The light scattered by such a planet will vary in intensity and colour as the planet rotates; the resulting light curve will contain information about the planet's properties. Here we report a model that predicts features that should be discernible in light curves obtained by low-precision photometry. For extrasolar planets similar to Earth we expect daily flux variations up to hundreds of percent, depending sensitively on ice and cloud cover. Qualitative changes in surface or climate generate significant changes in the predicted light curves. This work suggests that the meteorological variability and the rotation period of an Earth-like planet could be derived from photometric observations. Other properties such as the composition of the surface (e.g., ocean versus land fraction), climate indicators (for example ice and cloud cover), and perhaps even signatures of Earth-like plant life could be constrained or possibly, with further study, even uniquely determined.Comment: Published in Nature. 9 pages including 3 figure
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