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    Constructional Volcanic Edifices on Mercury: Candidates and Hypotheses of Formation

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    Mercury, a planet with a predominantly volcanic crust, has perplexingly few, if any, constructional volcanic edifices, despite their common occurrence on other solar system bodies with volcanic histories. Using image and topographical data from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, we describe two small (< 15 km‚Äźdiameter) prominences with shallow summit depressions associated with volcanically flooded impact features. We offer both volcanic and impact‚Äźrelated interpretations for their formation, and then compare these landforms with volcanic features on Earth and the Moon. Though we cannot definitively conclude that these landforms are volcanic, the paucity of constructional volcanic edifices on Mercury is intriguing in itself. We suggest that this lack is because volcanic eruptions with sufficiently low eruption volumes, rates, and flow lengths, suitable for edifice construction, were highly spatiotemporally restricted during Mercury's geological history. We suggest that volcanic edifices may preferentially occur in association with late‚Äźstage, post‚Äźimpact effusive volcanic deposits. The ESA/JAXA BepiColombo mission to Mercury will be able to investigate further our candidate volcanic edifices, search for other, as‚Äźyet unrecognized edifices beneath the detection limits of MESSENGER data, and test our hypothesis that edifice construction is favored by late‚Äźstage, low‚Äźvolume effusive eruptions

    A comprehensive survey of hearing questionnaires: how many are there, what do they measure, and how have they been validated?

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    The self-report questionnaire is a popular tool for measuring outcomes in trials of interventions for hearing impairment. Many have been designed over the last fifty years, and there is no single standard questionnaire that is widely accepted and used. We felt it would be a valuable resource to have a comprehensive collection of all adult hearing-loss questionnaires (excluding those wholly devoted to tinnitus, children, or cochlear implants) and to survey their degree of validation. We collated copies of every published hearing difficulty questionnaire that we could find. The search was primarily done by iterative reference searching. Questionnaire topics were obtained by mapping the text of each questionnaire onto a set of categories; reports of validation methods were taken from the primary paper(s) on each questionnaire. In total we found 139 hearing-specific questionnaires (though many others were found that were primarily about something else). Though not formally systematic, we believe that we have included every questionnaire that is important, most of those of some notice, and a fair fraction of those obscure. We classified 111 as ‚Äúprimary‚ÄĚ and the remaining 28 as ‚Äúcontractions‚ÄĚ, being shortened versions of a primary without any new questions. In total, there were 3618 items across all the primary questionnaires. The median number of items per questionnaire was 20; the maximum was 158. Across all items, about one third were concerned with the person‚Äôs own hearing, another third with the repercussions of it, and about a quarter with hearing aids. There was a wide range in validation methods, from only using items chosen statistically from wider pools and with formal validation against independent measures of clinical outcomes, to just reporting a correlation with an audiogram measure of hearing loss. The ‚Äústate of play‚ÄĚ of the field of hearing questionnaires will be discussed

    Back to the big picture

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    We distinguish between two different strategies in methodology of economics. The big picture strategy, dominant in the twentieth century, ascribed to economics a unified method and evaluated this m..
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