1,071 research outputs found

    Testing the limits of SMILES-based de novo molecular generation with curriculum and deep reinforcement learning

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    Deep reinforcement learning methods have been shown to be potentially powerful tools for de novo design. Recurrent-neural-network-based techniques are the most widely used methods in this space. In this work we examine the behaviour of recurrent-neural-network-based methods when there are few (or no) examples of molecules with the desired properties in the training data. We find that targeted molecular generation is usually possible, but the diversity of generated molecules is often reduced and it is not possible to control the composition of generated molecular sets. To help overcome these issues, we propose a new curriculum-learning-inspired recurrent iterative optimization procedure that enables the optimization of generated molecules for seen and unseen molecular profiles, and allows the user to control whether a molecular profile is explored or exploited. Using our method, we generate specific and diverse sets of molecules with up to 18 times more scaffolds than standard methods for the same sample size; however, our results also point to substantial limitations of one-dimensional molecular representations, as used in this space. We find that the success or failure of a given molecular optimization problem depends on the choice of simplified molecular-input line-entry system (SMILES)

    Mind the gap? The persistence of pathological discourses in urban regeneration policy

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    Urban regeneration policy has historically framed policy problems using a discourse that pathologises areas and spatial communities. Since 2001 in England, and 2002 in Scotland a structural change in policy has occurred where citywide partnerships are now meant overcome structural spatial inequalities, countering pathological explanations. This paper uses historical and discourse analysis to evaluate one of the major community regeneration strategies developed by the Scottish Executive in 2002: Better Communities in Scotland: Closing the Gap. It seeks to ask whether structural change in policy was paralleled by discursive change; what discursive path dependence is evidenced? The text is placed in the historic context of UK urban renewal policies dating back to the launch of the Urban Programme in 1968 and particularly the policy discourse created by the influential Conservative government policy of 1988 New Life for Urban Scotland and the wider discourses of poverty and neighbourhood renewal policy created by Labour governments since 1997. The close textual analysis of the text shows that Better Communities in Scotland continues to pathologise spatial communities. Although this suggests a degree of historical path dependency, the historic breadth of the analysis also problematises simple historical determinism

    On the side of the angels: community involvement in the governance of neighbourhood renewal.

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    This article draws upon the authors’ experiences of community-led regeneration developed while members of the National Evaluation Team for the NDC Programme. The article continues the focus on urban regeneration adopted in a range of outputs from two of the authors over the last decade. In assessing how the term community has been defined by policy-makers and the challenges involved in empowering communities, the output was aimed at both academic and user communities. For its direct relevance to communities involved in regeneration, the article was awarded the 2006 Sam Aaronovitch Prize, awarded annually by the journal Local Economy

    Responsible participation and housing: restoring democratic theory to the scene

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    Tensions between individual liberty and collective social justice characterise many advanced liberal societies. These tensions are reflected in the challenges posed for representative democracy both by participatory democratic practices and by the current emphasis on (so-called) responsible participation. Based on the example of ‘community’ housing associations in Scotland, this paper explores these tensions. It is argued that the critique of responsibility may have been over-stated – that, in particular, ‘community’ housing associations offer the basis for relatively more inclusive and effective processes of decision-making than council housing, which relies on the traditional processes and institutions of representative local government for its legitimacy

    Assessing the spatial impact of policy interventions on real-estate values: an exemplar of the use of the hybrid hedonic/repeat-sales method

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    This paper sets out to make a contribution to the extensive literature that seeks to develop methods that allow rigorous and robust analysis of the spatial and temporal impacts of public policy interventions on property (real-estate) values. It argues that the hybrid repeat-sales/hedonic method developed in real-estate studies over the last 30 years has considerable, but as yet under-developed, potential as a policy analysis tool. Using data from Glasgow, UK, the empirical analysis illustrates how the technique can be used to understand the spatial spillovers and the dynamic temporal effects of a historic £100 million state-led, area-based, urban-renewal programme, New Life for Urban Scotland. The paper concludes by arguing that, with the rise in the availability of rich geocoded, micro-datasets, this framework is sufficiently flexible to be used to evaluate the real-estate market impacts of a wide range of public policy interventions. Significantly, as the case study demonstrates, the framework overcomes some of the sustained criticisms of the more commonly used hedonic modelling approach. There is, however, still much to do to enhance the technical qualities of the models through further application

    The decline and rise of neighbourhoods: the importance of neighbourhood governance

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    There is a substantial literature on the explanation of neighbourhood change. Most of this literature concentrates on identifying factors and developments behind processes of decline. This paper reviews the literature, focusing on the identification of patterns of neighbourhood change, and argues that the concept of neighbourhood governance is a missing link in attempts to explain these patterns. Including neighbourhood governance in the explanations of neighbourhood change and decline will produce better explanatory models and, finally, a better view about what is actually steering neighbourhood change

    Spontaneous chirality through mixing achiral components : A twist-bend nematic phase driven by hydrogen-bonding between unlike components

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    Acknowledgments: The work was supported by the National Science Centre (Poland) under the grant no. 2016/22/A/ST5/00319. RW gratefully acknowledges the Carnegie Trust for the Universities of Scotland for funding the award of a PhD scholarship.Peer reviewedPostprin

    Willingness to participate in future HIV prevention studies among gay and bisexual men in Scotland, UK: a challenge for intervention trials

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    This article examines willingness to participate in future HIV prevention research among gay and bisexual men in Scotland, UK. Anonymous, self-complete questionnaires and Orasure Gäó oral fluid samples were collected in commercial gay venues. 1,320 men were eligible for inclusion. 78.2% reported willingness to participate in future HIV prevention research; 64.6% for an HIV vaccine, 57.4% for a behaviour change study, and 53.0% for a rectal microbicide. In multivariate analysis, for HIV vaccine research, greater age, minority ethnicity, and not providing an oral fluid sample were associated with lower willingness; heterosexual orientation and not providing an oral fluid sample were for microbicides; higher education and greater HIV treatment optimism were for behaviour change. STI testing remained associated with being more willing to participate in microbicide research and frequent gay scene use remained associated with being more willing to participate in behaviour change research. Having an STI in the past 12 months remained significantly associated with being willing to participate in all three study types. There were no associations between sexual risk behaviour and willingness. Although most men expressed willingness to participate in future research, recruitment of high-risk men, who have the potential to benefit most, is likely to be more challenging
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