226 research outputs found

    Seamount influences on mid-water shrimps (Decapoda) and Gnathophausiids (Lophogastridea) of the South-West Indian ridge

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    This study was conducted under the UNDP/IUCN project, funded by the Global Environment Facility (GEF). The authors thank the School of Biology at the University of St Andrews and the National Environmental Research Council (NERC) for funding toward Tom B Letessier's PhD.Maintenance of often-observed elevated levels of pelagic diversity and biomass on seamounts, that are of relevance to conservation and fishery management, involves complex interactions between physical and biological variables that remain poorly understood. To untangle these biophysical processes we explore factors influencing the distribution of epi- and meso-pelagic (0–1000 m) micronektonic crustaceans (>15 mm; order Lophogastridea, family Gnathophausiidea; and order Decapoda) on and off seamounts along the South West Indian Ridge (SWIR, 27° to 42°S) and on a seamount off the Madagascar Ridge (31.6°S, 42.8°E). Thirty-one species of micronektic crustaceans were caught using mid-water trawls within the study are but there was no apparent latitude-related patterns in species richness or abundance. Species richness predicted by rarefraction curves and numerical abundance was highest in the vicinity (800 m). The dominant species assemblage comprised the shrimps Systellaspis debilis (37%) and Sergia prehensilis (34%), and was restricted to seamounts on the subtropical SWIR. Our observations suggest that the ‘oasis effect’ of seamounts conventionally associated with higher trophic levels is also applicable to pelagic micronektic crustaceans at lower trophic levels. We suggest that the enhanced biomass and species richness attributed is due to ‘habitat enrichment’, whereby seamounts provide favourable habitats for both pelagic and bentho-pelagic mid-water crustaceans.PostprintPeer reviewe

    Transformative social innovation and (dis)empowerment

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    This article responds to increasing public and academic discourses on social innovation, which often rest on the assumption that social innovation can drive societal change and empower actors to deal with societal challenges and a retreating welfare state. In order to scrutinise this assumption, this article proposes a set of concepts to study the dynamics of transformative social innovation and underlying processes of multi-actor (dis)empowerment. First, the concept of transformative social innovation is unpacked by proposing four foundational concepts to help distinguish between different pertinent ‘shades’ of change and innovation: 1) social innovation, (2) system innovation, (3) game-changers, and (4) narratives of change. These concepts, invoking insights from transitions studies and social innovations literature, are used to construct a conceptual account of how transformative social innovation emerges as a co-evolutionary interaction between diverse shades of change and innovation. Second, the paper critically discusses the dialectic nature of multi-actor (dis)empowerment that underlies such processes of change and innovation. The paper then demonstrates how the conceptualisations are applied to three empirical case-studies of transformative social innovation: Impact Hub, Time Banks and Credit Unions. In the conclusion we synthesise how the concepts and the empirical examples help to understand contemporary shifts in societal power relations and the changing role of the welfare state

    Heritability and genome-wide analyses of problematic peer relationships during childhood and adolescence

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    Peer behaviour plays an important role in the development of social adjustment, though little is known about its genetic architecture. We conducted a twin study combined with a genome-wide complex trait analysis (GCTA) and a genome-wide screen to characterise genetic influences on problematic peer behaviour during childhood and adolescence. This included a series of longitudinal measures (parent-reported Strengths-and-Difficulties Questionnaire) from a UK population-based birth-cohort (ALSPAC, 4–17 years), and a UK twin sample (TEDS, 4–11 years). Longitudinal twin analysis (TEDS; N ≤ 7,366 twin pairs) showed that peer problems in childhood are heritable (4–11 years, 0.60 < twin-h 2 ≤ 0.71) but genetically heterogeneous from age to age (4–11 years, twin-r g = 0.30). GCTA (ALSPAC: N ≤ 5,608, TEDS: N ≤ 2,691) provided furthermore little support for the contribution of measured common genetic variants during childhood (4–12 years, 0.02<GCTA−h2Meta ≤ 0.11) though these influences become stronger in adolescence (13–17 years, 0.14<GCTA−h2ALSPAC ≤ 0.27). A subsequent cross-sectional genome-wide screen in ALSPAC (N ≤ 6,000) focussed on peer problems with the highest GCTA-heritability (10, 13 and 17 years, 0.0002 < GCTA-P ≤ 0.03). Single variant signals (P ≤ 10−5) were followed up in TEDS (N ≤ 2835, 9 and 11 years) and, in search for autism quantitative trait loci, explored within two autism samples (AGRE: N Pedigrees = 793; ACC: N Cases = 1,453/N Controls = 7,070). There was, however, no evidence for association in TEDS and little evidence for an overlap with the autistic continuum. In summary, our findings suggest that problematic peer relationships are heritable but genetically complex and heterogeneous from age to age, with an increase in common measurable genetic variation during adolescence

    TRANSIT Working Paper # 7

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    A previous version of this paper has been part of TRANSIT Deliverable 3.3 (July 2016), the second prototype of TSI theory.[Abstract] This working paper presents a set of propositions about the agency and dynamics of transformative social innovation (TSI) that have been developed as part of an EU-funded research project entitled “TRANsformative Social Innovation Theory” (TRANSIT; 2014-2017). These TSI propositions represent first steps towards the development of a new theory of TSI, taking the form of proto-explanations of the agency and dynamics of TSI, based on the bringing together of our empirical observations on TSI and the project's theoretical reviews and theoretical framings. Ideally this working paper should be read in conjunction with the working paper entitled “A framework for transformative social innovation” (Haxeltine et al 2016) which presents in skeletal terms the theoretical and conceptual framing of TSI developed in the TRANSIT project. This TSI framework builds on sustainability transition studies, social innovation research, social psychology studies of empowerment and other several other areas of social theory to deliver a bespoke theoretical and conceptual framework that is grounded in a relational ontology and which is being employed as a platform for the development of a middle-range theory of TSI. Next we provide a very brief overview of some key elements of the framework, in particular how we conceptualise social innovation, transformative change, and transformative social innovation. Propositions were developed for each of four relational dimensions implied by the TSI framework with also a brief statement of the topic addressed by each of the twelve propositions.This article is based on research carried out as part of the Transformative Social Innovation Theory (“TRANSIT”) project, which is funded by the European Union's Seventh Framework Programme (FP7) under grant agreement 61316

    Organism-sediment interactions govern post-hypoxia recovery of ecosystem functioning

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    Hypoxia represents one of the major causes of biodiversity and ecosystem functioning loss for coastal waters. Since eutrophication-induced hypoxic events are becoming increasingly frequent and intense, understanding the response of ecosystems to hypoxia is of primary importance to understand and predict the stability of ecosystem functioning. Such ecological stability may greatly depend on the recovery patterns of communities and the return time of the system properties associated to these patterns. Here, we have examined how the reassembly of a benthic community contributed to the recovery of ecosystem functioning following experimentally-induced hypoxia in a tidal flat. We demonstrate that organism-sediment interactions that depend on organism size and relate to mobility traits and sediment reworking capacities are generally more important than recovering species richness to set the return time of the measured sediment processes and properties. Specifically, increasing macrofauna bioturbation potential during community reassembly significantly contributed to the recovery of sediment processes and properties such as denitrification, bedload sediment transport, primary production and deep pore water ammonium concentration. Such bioturbation potential was due to the replacement of the small-sized organisms that recolonised at early stages by large-sized bioturbating organisms, which had a disproportionately stronger influence on sediment. This study suggests that the complete recovery of organism-sediment interactions is a necessary condition for ecosystem functioning recovery, and that such process requires long periods after disturbance due to the slow growth of juveniles into adult stages involved in these interactions. Consequently, repeated episodes of disturbance at intervals smaller than the time needed for the system to fully recover organism-sediment interactions may greatly impair the resilience of ecosystem functioning.

    Treating the placenta to prevent adverse effects of gestational hypoxia on fetal brain development.

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    Some neuropsychiatric disease, including schizophrenia, may originate during prenatal development, following periods of gestational hypoxia and placental oxidative stress. Here we investigated if gestational hypoxia promotes damaging secretions from the placenta that affect fetal development and whether a mitochondria-targeted antioxidant MitoQ might prevent this. Gestational hypoxia caused low birth-weight and changes in young adult offspring brain, mimicking those in human neuropsychiatric disease. Exposure of cultured neurons to fetal plasma or to secretions from the placenta or from model trophoblast barriers that had been exposed to altered oxygenation caused similar morphological changes. The secretions and plasma contained altered microRNAs whose targets were linked with changes in gene expression in the fetal brain and with human schizophrenia loci. Molecular and morphological changes in vivo and in vitro were prevented by a single dose of MitoQ bound to nanoparticles, which were shown to localise and prevent oxidative stress in the placenta but not in the fetus. We suggest the possibility of developing preventative treatments that target the placenta and not the fetus to reduce risk of psychiatric disease in later life

    Solidarity in spaces of ‘care and custody’: the hospitality politics of immigration detention visiting

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    This article contributes to criminological understanding of immigration detention by highlighting the volunteer visiting as a space of embodied thinking about critical responses to the burgeoning crimmigration system. It draws from interview material with volunteer visitors and people held in immigration detention centres to assess conceptual relevance of critical hospitality studies for anti-border practice. Both within Derridean scholarship on hospitality and in social-discourses on migration, host/citizen and guest/migrant identifications are understood as stable subject positions. I argue that to support resistance to deportation and establish mutual solidarity and cooperation in this context, detention visitors adopt multiple strategies of hospitality that position themselves as visitors as well as hosts. By counter-posing differing ways that volunteers occupy these roles, I show how the co-presence of divergent ways of offering hospitality allow visitors to navigate the complicities that necessarily afflict support in solidarity with migrants in carceral spaces of border control

    Quantifying Variability of Avian Colours: Are Signalling Traits More Variable?

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    Background Increased variability in sexually selected ornaments, a key assumption of evolutionary theory, is thought to be maintained through condition-dependence. Condition-dependent handicap models of sexual selection predict that (a) sexually selected traits show amplified variability compared to equivalent non-sexually selected traits, and since males are usually the sexually selected sex, that (b) males are more variable than females, and (c) sexually dimorphic traits more variable than monomorphic ones. So far these predictions have only been tested for metric traits. Surprisingly, they have not been examined for bright coloration, one of the most prominent sexual traits. This omission stems from computational difficulties: different types of colours are quantified on different scales precluding the use of coefficients of variation. Methodology/Principal Findings Based on physiological models of avian colour vision we develop an index to quantify the degree of discriminable colour variation as it can be perceived by conspecifics. A comparison of variability in ornamental and non-ornamental colours in six bird species confirmed (a) that those coloured patches that are sexually selected or act as indicators of quality show increased chromatic variability. However, we found no support for (b) that males generally show higher levels of variability than females, or (c) that sexual dichromatism per se is associated with increased variability. Conclusions/Significance We show that it is currently possible to realistically estimate variability of animal colours as perceived by them, something difficult to achieve with other traits. Increased variability of known sexually-selected/quality-indicating colours in the studied species, provides support to the predictions borne from sexual selection theory but the lack of increased overall variability in males or dimorphic colours in general indicates that sexual differences might not always be shaped by similar selective forces
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