1,287 research outputs found

    Using Simulated Micrometeoroid Impacts to Understand the Progressive Space Weathering of the Surface of Mercury

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    The surfaces of airless bodies such as Mercury are continually modified by space weathering, which is driven by micrometeoroid impacts and solar wind irradiation. Space weathering alters the chemical composition, microstructure, and spectral properties of surface regolith. In lunar and ordinarychondritic style space weathering, these processes affect the reflectance properties by darkening (lowering of reflectance), reddening (increasing reflectance with increasing wavelength), and attenuation of characteristic absorption features. These optical changes are driven by the production of nanophase Febearing particles (npFe). While our understanding of these alteration processes has largely been based on data from the Moon and near-Earth S-type asteroids, the space weathering environment at Mercury is much more extreme. The surface of Mercury experiences a more intense solar wind flux and higher velocity micrometeoroid impacts than its planetary counterparts at 1 AU. Additionally, the composition of Mercurys surface varies significantly from that of the Moon. Most notably, a very low albedo unit has been identified on Mercurys surface, known as the low reflectance material (LRM). This unit is enriched with up to 4 wt.% carbon, likely in the form of graphite, over the local mean. In addition, the surface concentration of Fe across Mercurys surface is low (<2 wt.%) compared to the Moon. Our understanding of how these low-Fe and carbon phases are altered as a result of space weathering processes is limited. Since Fe plays a critical role in the development of space weathering features on other airless surfaces (e.g., npFe), its limited availability on Mercury may strongly affect the space weathering features in surface materials. In order to understand how space weathering affects the chemical, microstructural, and optical properties of the surface of Mercury, we can simulate these processes in the laboratory [7]. Here we used pulsed laser irradiation to simulate the short duration, high temperature events associated with micrometeoroid impacts. We used forsteritic olivine, likely present on the Mercurian surface, with varying FeO contents, each mixed with graphite, in our experiments. We then performed reflectance spectroscopy and electron microscopy to investigate the spectral, chemical, and microstructural changes in these samples

    Making progress: the role of cancer councils in Australia in indigenous cancer control

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    Background: Indigenous Australians have poorer outcomes from cancer for a variety of reasons including poorer participation in screening programs, later diagnosis, higher rates of cancer with poor prognosis and poorer uptake and completion of treatment. Cancer prevention and support for people with cancer is part of the core business of the State and Territory Cancer Councils. To support sharing of lessons learned, this paper reports an environmental scan undertaken in 2010 in cancer councils (CCs) nationwide that aimed to support Indigenous cancer control. Methods: The methods replicated the approach used in a 2006 environmental scan of Indigenous related activity in CCs. The Chief Executive Officer of each CC nominated individuals for interview. Interviews explored staffing, projects, programs and activities to progress cancer control issues for Indigenous Australians, through phone or face-to-face interviews. Reported initiatives were tabulated using predetermined categories of activity and summaries were returned to interviewees, the Aboriginal and Torres Strait Islander Subcommittee and Chief Executive Officers for verification.Results: All CCs participated and modest increases in activity had occurred in most states since 2006 through different means. Indigenous staff numbers were low and no Indigenous person had yet been employed in smaller CCs; no CC had an Indigenous Board member and efforts at capacity building were often directed outside of the organisation. Developing partnerships with Indigenous organisations were ongoing. Acknowledgement and specific mention of Indigenous people in policy was increasing. Momentum increased following the establishment of a national subcommittee which increased the profile of Indigenous issues and provided collegial and practical support for those committed to reducing Indigenous cancer disparities. Government funding of “Closing the Gap” and research in the larger CCs have been other avenues for increasing knowledge and activity in Indigenous cancer control. Conclusions: This environmental scan measured progress, allowed sharing of information and provided critical assessment of progress across areas of importance for increasing Indigenous cancer control. Structured examination of policies, institutional support systems, programs and interventions is a useful means of highlighting opportunities for progress with minority groups relevant for many organisations. Progress has occurred with momentum likely to increase in the future and benefit from commitment to long-term monitoring and sharing of achievements

    Predictors of Shared Decision Making and Level of Agreement between Consumers and Providers in Psychiatric Care

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    The purpose of this study was to quantitatively examine elements of shared decision making (SDM), and to establish empirical evidence for factors correlated with SDM and the level of agreement between consumer and provider in psychiatric care. Transcripts containing 128 audio-recorded medication check-up visits with eight providers at three community mental health centers were rated using the Shared Decision Making scale, adapted from Braddock’s Informed Decision Making Scale (Braddock et al., 1997; 1999; 2008). Multilevel regression analyses revealed that greater consumer activity in the session and greater decision complexity significantly predicted the SDM score. The best predictor of agreement between consumer and provider was “exploration of consumer preference,” with a four-fold increase in full agreement when consumer preferences were discussed more completely. Enhancing active consumer participation, particularly by incorporating consumer preferences in the decision making process appears to be an important factor in SDM

    Medical Biochemistry Without Rote Memorization: Multi-Institution Implementation And Student Perceptions Of A Nationally Standardized Metabolic Map For Learning And Assessment

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    Despite the growing number of patients worldwide with metabolism-related chronic diseases, medical biochemistry education is commonly perceived as focusing on recall of facts irrelevant for patient care. The authors suggest that this focus on rote memorization of pathways creates excessive cognitive load that may interfere with learners’ development of an integrated understanding of metabolic regulation and dysregulation. This cognitive load can be minimized by providing appropriate references during learning and assessment. Biochemistry educators collaborated to develop a medically relevant Pathways of Human Metabolism map (MetMap) that is now being used at many medical schools as a nationally standardized resource during learning and assessments. To assess impact, students from three medical schools were surveyed about its benefits and disadvantages. Responses were obtained from 481 students (84%) and were examined using thematic analysis. Five main themes emerged as perceived benefits of using the MetMap: 1) aids visual and mental organization, 2) promotes deep learning and applied understanding, 3) decreases emphasis on memorization, 4) reduces anxiety on exams, and 5) aids recall. Perceived disadvantages were: 1) fear of under-preparation for licensing exams, 2) overwhelming nature of the map, and 3) reduced motivation for and time spent studying. Results affirm that students perceive use of the MetMap promotes focus on broader metabolic concepts and deep versus surface learning, supporting a shift in cognitive load toward desired goals. Although the long-term impact on learning needs to be further studied, the use of the MetMap represents a step toward open-reference exams that reflect “real world” practice

    Predictors of Shared Decision Making and Level of Agreement between Consumers and Providers in Psychiatric Care

    Get PDF
    The purpose of this study was to quantitatively examine elements of shared decision making (SDM), and to establish empirical evidence for factors correlated with SDM and the level of agreement between consumer and provider in psychiatric care. Transcripts containing 128 audio-recorded medication check-up visits with eight providers at three community mental health centers were rated using the Shared Decision Making scale, adapted from Braddock’s Informed Decision Making Scale (Braddock et al., 1997; 1999; 2008). Multilevel regression analyses revealed that greater consumer activity in the session and greater decision complexity significantly predicted the SDM score. The best predictor of agreement between consumer and provider was “exploration of consumer preference,” with a four-fold increase in full agreement when consumer preferences were discussed more completely. Enhancing active consumer participation, particularly by incorporating consumer preferences in the decision making process appears to be an important factor in SDM

    Non-pharmacological interventions for ADHD in school settings: an overarching synthesis of systematic reviews

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    OBJECTIVE: This overarching synthesis brings together the findings of four systematic reviews including 138 studies focused on non-pharmacological interventions for ADHD used in school settings. These reviews considered the effectiveness of school-based interventions for ADHD, attitudes toward and experience of school-based interventions for ADHD, and the experience of ADHD in school settings. METHOD: We developed novel methods to compare the findings across these reviews inductively and deductively. RESULTS: Key contextual issues that may influence the effectiveness and implementation of interventions include the relationships that pupils with ADHD have with their teachers and peers, the attributions individuals make about the etiology of ADHD, and stigma related to ADHD or intervention attendance. CONCLUSION: Although we found some positive effects for some outcomes and intervention categories, heterogeneity in effect size estimates and research evidence suggests a range of diverse contextual factors potentially moderate the implementation and effectiveness of school-based interventions for ADHD.National Institute for Health Research Health Technology Assessment (NIHR HTA) programNIHR Collaboration for Leadership in Applied HealthResearch and Care South West Peninsula (PenCLAHRC

    A Coding System to Measure Elements of Shared Decision Making During Psychiatric Visits

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    Objective: Shared decision making is widely recognized to facilitate effective health care. The purpose of this study was to assess the applicability and usefulness of a scale to measure the presence and extent of shared decision making in clinical decisions in psychiatric practice. Methods: A coding scheme assessing shared decision making in general medical settings was adapted to mental health settings, and a manual for using the scheme was created. Trained raters used the adapted scale to analyze 170 audio-recordings of medication check-up visits with either psychiatrists or nurse practitioners. The scale assessed the level of shared decision making based on the presence of nine specific elements. Interrater reliability was examined, and the frequency with which elements of shared decision making were observed was documented. The association between visit length and extent of shared decision making was also examined. Results: Interrater reliability among three raters on a subset of 20 recordings ranged from 67% to 100% agreement for the presence of each of the nine elements of shared decision making and 100% for the agreement between provider and consumer on decisions made. Of the 170 sessions, 128 (75%) included a clinical decision. Just over half of the decisions (53%) met minimum criteria for shared decision making. Shared decision making was not related to visit length after the analysis controlled for the complexity of the decision. Conclusions: The rating scale appears to reliably assess shared decision making in psychiatric practice and could be helpful for future research, training, and implementation efforts

    Variation in abundance, diversity and composition of coral reef fishes with increasing depth at a submerged shoal in the northern Great Barrier Reef

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    Coral reef fishes often exhibit specific or restricted depth distributions, but the factors (biotic or abiotic) that influence patterns of depth use are largely unknown. Given inherent biological gradients with depth (i.e. light, nutrients, habitat, temperature), it is expected that fishes may exploit certain depths within their environment to seek out more favourable conditions. This study used baited remote underwater video (BRUV) systems to document variation in the taxonomic and functional (trophic and size) structure of a fish assemblage along a shallow to upper-mesophotic depth gradient (13–71 m) at a submerged, offshore shoal in the northern Great Barrier Reef. BRUVs were deployed during two separate time periods (February and August 2017), to separately examine patterns of depth use. Both the relative abundance and diversity of reef fishes declined with depth, and there were pronounced differences in the taxonomic and functional structure of the fish assemblage across the depth gradient. In shallow habitats ( 30 m) was dominated by piscivores and mobile invertivores. Depth and habitat type were also strong predictors for important fisheries species such as coral trout (Plectropomus spp.), emperors (Lethrinus spp.) and trevallies (Carangid spp.). We found limited evidence of temporal changes in depth and habitat use by fishes (including fisheries target species), although recorded temperatures were 4 °C higher in February 2017 compared to August 2017
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