191 research outputs found

    The adaptation of self-report measures to the needs of people with intellectual disabilities : a systematic review

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    Persons with intellectual disabilities (ID) may have difficulties providing reliable and valid accounts of their personal experiences through self-report measures. The aim of the current study was to systematically review the peer-reviewed research literature on the adaptations needed to develop “ID-inclusive” self-report measures. A search of APA PsycInfo, PubMed, Web of Science, and Google Scholar identified 49 studies that met inclusion criteria. A GRADE-CERQual assessment was performed to determine the level of confidence in the review findings. One hundred sixty-one recommendations for the development of “ID-inclusive” self-report measures were extracted from 49 included studies. Recommendations were presented in a GRADE-CERQual Summary of Findings table, according to a five-stage model of instrument development. This review offers much-needed practical guidance for clinicians and researchers on how to develop “ID-inclusive” self-report measures. Recommendations for future research about self-report instrument development for use with people with ID are presented

    Early warning of critical transitions in biodiversity from compositional disorder

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    Global environmental change presents a clear need for improved leading indicators of critical transitions, especially those that can be generated from compositional data and that work in empirical cases. Ecological theory of community dynamics under environmental forcing predicts an early replacement of slowly replicating and weakly competitive “canary” species by slowly replicating but strongly competitive “keystone” species. Further forcing leads to the eventual collapse of the keystone species as they are replaced by weakly competitive but fast‐replicating “weedy” species in a critical transition to a significantly different state. We identify a diagnostic signal of these changes in the coefficients of a correlation between compositional disorder and biodiversity. Compositional disorder measures unpredictability in the composition of a community, while biodiversity measures the amount of species in the community. In a stochastic simulation, sequential correlations over time switch from positive to negative as keystones prevail over canaries, and back to positive with domination of weedy species. The model finds support in empirical tests on multi‐decadal time series of fossil diatom and chironomid communities from lakes in China. The characteristic switch from positive to negative correlation coefficients occurs for both communities up to three decades preceding a critical transition to a sustained alternate state. This signal is robust to unequal time increments that beset the identification of early‐warning signals from other metrics

    Long-term perspectives on terrestrial and aquatic carbon cycling from palaeolimnology

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    Lakes are active processors and collectors of carbon (C) and thus recognized as quantitatively important within the terrestrial C cycle. Better integration of palaeolimnology (lake sediment core analyses) with limnological or modelling approaches has the potential to enhance understanding of lacustrine C processing and sequestration. Palaeolimnology simultaneously assimilates materials from across lake habitats, terrestrial watersheds and airsheds to provide a uniquely broad overview of the terrestrial-atmospheric-aquatic linkages across spatial scales. The examination of past changes over decadal-millenial timescales via palaeolimnology can inform understanding and prediction of future changes in C cycling. With a particular, but not exclusive, focus on northern latitudes we examine the methodological approaches of palaeolimnology, focusing on how relatively standard and well tested techniques might be applied to address questions of relevance to the C cycle. We consider how palaeolimnology, limnology and sedimentation studies might be linked to provide more quantitative and holistic estimates lake C cycling. Finally, we use palaeolimnological examples to consider how changes such as terrestrial vegetation cover, permafrost thaw, the formation of new lakes and reservoirs, hydrological modification of inorganic C processing, land use change, soil erosion and disruption to global nitrogen and phosphorus cycles might influence lake C cycling

    Safe and just operating spaces for regional social-ecological systems

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    Humanity faces a major global challenge in achieving wellbeing for all, while simultaneously ensuring that the biophysical processes and ecosystem services that underpin wellbeing are exploited within scientifically informed boundaries of sustainability. We propose a framework for defining the safe and just operating space for humanity that integrates social wellbeing into the original planetary boundaries concept (Rockström et al., 2009a,b) for application at regional scales. We argue that such a framework can: (1) increase the policy impact of the boundaries concept as most governance takes place at the regional rather than planetary scale; (2) contribute to the understanding and dissemination of complexity thinking throughout governance and policy-making; (3) act as a powerful metaphor and communication tool for regional equity and sustainability. We demonstrate the approach in two rural Chinese localities where we define the safe and just operating space that lies between an environmental ceiling and a social foundation from analysis of time series drawn from monitored and palaeoecological data, and from social survey statistics respectively. Agricultural intensification has led to poverty reduction, though not eradicated it, but at the expense of environmental degradation. Currently, the environmental ceiling is exceeded for degraded water quality at both localities even though the least well-met social standards are for available piped water and sanitation. The conjunction of these social needs and environmental constraints around the issue of water access and quality illustrates the broader value of the safe and just operating space approach for sustainable development

    Palaeoseismology from microfabric and geochemical analysis of lacustrine sediment, Windermere, UK

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    Lake sediments commonly contain detrital layers that record events such as floods or earthquakes but these may be disturbed or partially destroyed by bioturbation. Here we use a novel combination of techniques to relate microscopic sediment fabric features to lake-basin scale processes. X-radiography and micro-XRF of cores are complemented by backscattered electron imagery and energy dispersive X-ray microanalysis of resin-embedded sediment. Together, the microfabric and geochemical methods enable the identification of clay-layer mass transport deposits despite bioturbational mixing of the original end members. Two cores with robust radionuclide chronologies contain correlative clay layers dated to 1979 (1974–1982) and 1979–1980 (1973–1986) respectively. These clay layers likely represent the distal turbidite generated by a major mass flow deposit identified from multibeam swath bathymetry and sediment grab sampling. A likely trigger for the mass flow and associated turbidity current is the 4.7 ML 1979 Carlisle earthquake. The lake basin slope was likely preconditioned for failure by increased sedimentary biogenic gas production and sediment in-wash as a result of anthropogenic activities, coupled with sediment disruption and dredging. This study highlights the effectiveness of microstratigraphic techniques in the recognition and characterisation of event layers in sediments where bioturbative disruption has occurred

    Human settlement of East Polynesia earlier, incremental, and coincident with prolonged South Pacific drought

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    The timing of human colonization of East Polynesia, a vast area lying between Hawai‘i, Rapa Nui, and New Zealand, is much debated and the underlying causes of this great migration have been enigmatic. Our study generates evidence for human dispersal into eastern Polynesia from islands to the west from around AD 900 and contemporaneous paleoclimate data from the likely source region. Lake cores from Atiu, Southern Cook Islands (SCIs) register evidence of pig and/or human occupation on a virgin landscape at this time, followed by changes in lake carbon around AD 1000 and significant anthropogenic disturbance from c. AD 1100. The broader paleoclimate context of these early voyages of exploration are derived from the Atiu lake core and complemented by additional lake cores from Samoa (directly west) and Vanuatu (southwest) and published hydroclimate proxies from the Society Islands (northeast) and Kiribati (north). Algal lipid and leaf wax biomarkers allow for comparisons of changing hydroclimate conditions across the region before, during, and after human arrival in the SCIs. The evidence indicates a prolonged drought in the likely western source region for these colonists, lasting c. 200 to 400 y, contemporaneous with the phasing of human dispersal into the Pacific. We propose that drying climate, coupled with documented social pressures and societal developments, instigated initial eastward exploration, resulting in SCI landfall(s) and return voyaging, with colonization a century or two later. This incremental settlement process likely involved the accumulation of critical maritime knowledge over several generations

    New DArT markers for oat provide enhanced map coverage and global germplasm characterization

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    BACKGROUND: Genomic discovery in oat and its application to oat improvement have been hindered by a lack of genetic markers common to different genetic maps, and by the difficulty of conducting whole-genome analysis using high-throughput markers. This study was intended to develop, characterize, and apply a large set of oat genetic markers based on Diversity Array Technology (DArT). RESULTS: Approximately 19,000 genomic clones were isolated from complexity-reduced genomic representations of pooled DNA samples from 60 oat varieties of global origin. These were screened on three discovery arrays, with more than 2000 polymorphic markers being identified for use in this study, and approximately 2700 potentially polymorphic markers being identified for use in future studies. DNA sequence was obtained for 2573 clones and assembled into a non-redundant set of 1770 contigs and singletons. Of these, 705 showed highly significant (Expectation < 10E-10) BLAST similarity to gene sequences in public databases. Based on marker scores in 80 recombinant inbred lines, 1010 new DArT markers were used to saturate and improve the 'Kanota' × 'Ogle' genetic map. DArT markers provided map coverage approximately equivalent to existing markers. After binning markers from similar clones, as well as those with 99% scoring similarity, a set of 1295 non-redundant markers was used to analyze genetic diversity in 182 accessions of cultivated oat of worldwide origin. Results of this analysis confirmed that major clusters of oat diversity are related to spring vs. winter type, and to the presence of major breeding programs within geographical regions. Secondary clusters revealed groups that were often related to known pedigree structure. CONCLUSION: These markers will provide a solid basis for future efforts in genomic discovery, comparative mapping, and the generation of an oat consensus map. They will also provide new opportunities for directed breeding of superior oat varieties, and guidance in the maintenance of oat genetic diversity
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