2,808 research outputs found

    The origins of radial fracture systems and associated large lava flows on Venus

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    Magellan images have revealed the existence of systems of radial fractures on venus that are very similar in form to terrestrial dike swarms such as the Mackenzie swarm in Northern Canada. The association of many of the fracture systems with lava flows, calderas, and volcanic edifices further support the idea of a dike emplacement origin. A global survey of the Magellan images has allowed the location of 300 such fracture systems. Two types of fracture systems are defined. A series of models were developed to simulate the emplacement of dikes on Venus. Observations of fracture lengths and widths were then used to constrain the emplacement conditions. The model results show that the great length and relatively large width of the fractures can only be explained if the dikes that produce them were emplaced in high driving pressure (pressure buffered) conditions. Such conditions imply high rates of melt production, which is consistent with the melt being derived directly from a plume head. We have recently modeled the vertical emplacement of a dike from the top of a mantle plume and calculated the eruption rates such a dike would produce on reaching the surface. This modeling shows that eruption rates of approximately 0.1 cu km/hr can readily be generated by such a dike, consistent with the above results. However, the sensitivity of the model to dike width and therefore driving pressure means that eruption rates from dikes emplaced from the base of the crust or the head of a mantle plume could be orders of magnitude higher than this. Clearly, therefore, the model needs to be refined in order to better constrain eruption conditions. However, it is worth noting here that the initial results do show that even for moderate dike widths, eruption rates could be at least on the order of those estimated for terrestrial flood basalts

    Young People Creating Belonging: spaces, sounds and sights

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    Report for ESRC-funded project exploring belonging among 'looked after' young people from across mainland and island Scotland. The project employed innovative visual and audial methods in multiple interviews with participants

    Brain Network Connectivity During Language Comprehension: Interacting Linguistic and Perceptual Subsystems.

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    The dynamic neural processes underlying spoken language comprehension require the real-time integration of general perceptual and specialized linguistic information. We recorded combined electro- and magnetoencephalographic measurements of participants listening to spoken words varying in perceptual and linguistic complexity. Combinatorial linguistic complexity processing was consistently localized to left perisylvian cortices, whereas competition-based perceptual complexity triggered distributed activity over both hemispheres. Functional connectivity showed that linguistically complex words engaged a distributed network of oscillations in the gamma band (20-60 Hz), which only partially overlapped with the network supporting perceptual analysis. Both processes enhanced cross-talk between left temporal regions and bilateral pars orbitalis (BA47). The left-lateralized synchrony between temporal regions and pars opercularis (BA44) was specific to the linguistically complex words, suggesting a specific role of left frontotemporal cross-cortical interactions in morphosyntactic computations. Synchronizations in oscillatory dynamics reveal the transient coupling of functional networks that support specific computational processes in language comprehension.This work was supported by an EPSRC grant to W.M.-W. (EP/F030061/1), an ERC Advanced Grant (Neurolex) to W.M.-W., and by MRC Cognition and Brain Sciences Unit (CBU) funding to W.M.-W. (U.1055.04.002.00001.01). Computing resources were provided by the MRC-CBU. Funding to pay the Open Access publication charges for this article was provided by the Advanced Investigator Grant (Neurolex) to W.D.M.-W.This is the final published version which appears at http://dx.doi.org/10.1093/cercor/bhu28

    Perceptual Enhancement for Arabic Reading: An Intervention to Support Fluency and Automaticity in Grade One

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    This study, conducted in the United Arab Emirates, piloted a curriculum to increase early grade reading fluency. A curriculum with enhanced perceptual features, such as font size and spacing was used with grade one students in four schools to detect any significant difference in students’ reading speed and reading accuracy after one year. Three hundred forty-five grade one students participated in the pilot—174 in the intervention group and 171 in the control group (ds= 0.33 0.47). At the end of the year, students in the intervention group read more letters and words correctly on average in one minute (p < .01) and in an entire text (p < .01 for letters; p < .001 for words) than those in the control group. These results suggest that curriculum with perceptual enhancement may be useful in facilitating early Arabic reading fluency

    Utility of routine screening for alpha-1 antitrypsin deficiency in patients with bronchiectasis

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    Alpha-1 antitrypsin deficiency (AATD) is a cause of bronchiectasis. Guidelines for bronchiectasis from the British Thoracic Society do not recommend to routinely test patients for AATD. In contrast, guidelines for AATD recommend routine screening. This contradiction, in part, results from the lack of data from large studies performing comprehensive screening. We screened 1600 patients with bronchiectasis at two centres in the UK from 2012 to 2016. In total, only eight individuals with AATD were identified representing 0.5% of the overall population. We conclude that routine screening for AATD in bronchiectasis in the UK has a low rate of detection. Further studies are required in different geographical regions, which may have a higher prevalence of AATD.info:eu-repo/semantics/publishedVersio

    Language Stimulation Techniques for Three-Year-Old and Four-Year-Old Children: Patterns of Language Development

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    One in 4 children in America ages 0-5 live in poverty (Federal Statistics, 2012); this group is far more likely to enter school as linguistically disadvantaged and the gap increases as they progress through school. This study investigates the effect of indirect language stimulation techniques on preschool children enrolled in Head Start programs in rural east Texas. The results from this study indicate differing patterns of language development between 3- and 4-year-old children, in response to their teacher’s use of indirect language stimulation techniques in normal day-to-day teaching. Specifically, the intervention using SPEAK techniques had a positive effect on the expressive English language vocabulary development of 4-year-old at-risk preschool children

    Grammatical analysis as a distributed neurobiological function.

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    This is the final version of the article. It first appeared from [publisher] via http://dx.doi.org/10.1002/hbm.22696Language processing engages large-scale functional networks in both hemispheres. Although it is widely accepted that left perisylvian regions have a key role in supporting complex grammatical computations, patient data suggest that some aspects of grammatical processing could be supported bilaterally. We investigated the distribution and the nature of grammatical computations across language processing networks by comparing two types of combinatorial grammatical sequences--inflectionally complex words and minimal phrases--and contrasting them with grammatically simple words. Novel multivariate analyses revealed that they engage a coalition of separable subsystems: inflected forms triggered left-lateralized activation, dissociable into dorsal processes supporting morphophonological parsing and ventral, lexically driven morphosyntactic processes. In contrast, simple phrases activated a consistently bilateral pattern of temporal regions, overlapping with inflectional activations in L middle temporal gyrus. These data confirm the role of the left-lateralized frontotemporal network in supporting complex grammatical computations. Critically, they also point to the capacity of bilateral temporal regions to support simple, linear grammatical computations. This is consistent with a dual neurobiological framework where phylogenetically older bihemispheric systems form part of the network that supports language function in the modern human, and where significant capacities for language comprehension remain intact even following severe left hemisphere damage.Computing resources were provided by the MRC-CBU. Li Su was partly supported by the Cambridge Dementia Biomedical Research Unit
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