81 research outputs found

    Role of Meteorite Impacts in the Origin of Life

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    The conditions, timing, and setting for the origin of life on Earth and whether life exists elsewhere in our solar system and beyond represent some of the most fundamental scientific questions of our time. Although the bombardment of planets and satellites by asteroids and comets has long been viewed as a destructive process that would have presented a barrier to the emergence of life and frustrated or extinguished life, we provide a comprehensive synthesis of data and observations on the beneficial role of impacts in a wide range of prebiotic and biological processes. In the context of previously proposed environments for the origin of life on Earth, we discuss how meteorite impacts can generate both subaerial and submarine hydrothermal vents, abundant hydrothermal–sedimentary settings, and impact analogues for volcanic pumice rafts and splash pools. Impact events can also deliver and/or generate many of the necessary chemical ingredients for life and catalytic substrates such as clays as well. The role that impact cratering plays in fracturing planetary crusts and its effects on deep subsurface habitats for life are also discussed. In summary, we propose that meteorite impact events are a fundamental geobiological process in planetary evolution that played an important role in the origin of life on Earth. We conclude with the recommendation that impact craters should be considered prime sites in the search for evidence of past life on Mars. Furthermore, unlike other geological processes such as volcanism or plate tectonics, impact cratering is ubiquitous on planetary bodies throughout the Universe and is independent of size, composition, and distance from the host star. Impact events thus provide a mechanism with the potential to generate habitable planets, moons, and asteroids throughout the Solar System and beyond

    The 'top 100' drugs and classes in England An updated 'starter formulary' for trainee prescribers.

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    AIMS: Prescribing is a complex skill required of doctors and, increasingly, other healthcare professionals. Use of a personal formulary can help to develop this skill. In 2006-9, we developed a core list of the 100 most commonly prescribed drugs. Our aim in the present study was to update this 'starter formulary' to ensure its continued relevance for prescriber training. METHODS: We analysed large contemporary primary and secondary care datasets to identify the most frequently prescribed medicinal products. Items were classified into natural groups, broadly following their British National Formulary classification. The resulting drug groups were included in the core list if they comprised ≥0.1% prescriptions in both settings or ≥0.2-0.3% prescriptions in one setting. Drugs from emergency guidelines that did not qualify by prescribing frequency completed the list. RESULTS: Over 1 billion primary care items and approximately 1.8 million secondary care prescriptions were analysed. The updated list comprises 81 drug groups commonly prescribed in both settings; 6 from primary care; 7 from secondary care; and 6 from emergency guidelines. 88% of the formulary was unchanged. Notable changes include entry of newer anti-epileptics and dipeptidyl peptidase-4 inhibitors and exit of phenytoin and thiazolidinediones. CONCLUSIONS: The relative stability of the core drug list over 9 years and the current update ensure that learning based on this list remains relevant to practice. Trainee prescribers may be encouraged to use this 'starter formulary' to develop a sound basis of prescribing knowledge and skills that they can subsequently apply more widely

    Gully Formation at the Haughton Impact Structure (Arctic Canada) Through the Melting of Snow and Ground Ice, with Implications for Gully Formation on Mars

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    The formation of gullies on Mars has been the topic of active debate and scientific study since their first discovery by Malin and Edgett in 2000. Several mechanisms have been proposed to account for gully formation on Mars, from dry mass movement processes, release of water or brine from subsurface aquifers, and the melting of near-surface ground ice or snowpacks. In their global documentation of martian gullies, report that gullies are confined to ~2783S and ~2872N latitudes and span all longitudes. Gullies on Mars have been documented on impact crater walls and central uplifts, isolated massifs, and on canyon walls, with crater walls being the most common situation. In order to better understand gully formation on Mars, we have been conducting field studies in the Canadian High Arctic over the past several summers, most recently in summer 2018 and 2019 under the auspices of the Canadian Space Agency-funded Icy Mars Analogue Program. It is notable that the majority of previous studies in the Arctic and Antarctica, including our recent work on Devon Island, have focused on gullies formed on slopes generated by regular endogenic geological processes and in regular bedrock. How-ever, as noted above, meteorite impact craters are the most dominant setting for gullies on Mars. Impact craters provide an environment with diverse lithologies including impact-generated and impact-modified rocks and slope angle, and thus greatly variable hill slope processes could occur within a localized area. Here, we investigate the formation of gullies within the Haughton impact structure and compare them to gullies formed in unimpacted target rock in the nearby Thomas Lee Inle

    Impact of Pharmacist-Led Diabetes Management in Primary Care Clinics

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    Purpose: Current literature supports that pharmacists effectively lower hemoglobin A1c (HbA1c) in diabetic patients. Little data exists on pharmacists’ effects on comorbidity management, patient satisfaction, or financial viability of these positions. This study looked to assess the impact of pharmacists on diabetes management compared to usual care. Methods: This multi-site, two-part study includes a retrospective chart review of patients referred to the pharmacist versus usual care within a large academic health system. The pharmacists collaborated under a consult agreement with primary care physicians. The second part of the study assessed patient satisfaction through an abbreviated CG-CAHPS survey. Results:A total of 206 patients with diabetes for an average of 12 years were included. The average patient age was 62 years with 60% of patients identifying as female and 81% as African-American. Patients were enrolled in a 2:1 fashion with 138 patients in the intervention group. Average baseline HbA1c was 10.1% in the intervention group and 9.3% in the control group (p= 0.0125). At 6 months, the mean change in HbA1c was -2.17% and 0.48% for the intervention and control groups respectively (p Conclusion: Pharmacists are effective at lowering HbA1c in primary care clinics, and patients were highly satisfied with these services. While direct revenue from this service did not meet cost, the pharmacist did positively affect outcomes that contribute to reimbursement. Treatment of Human Subjects: IRB review/approval required and obtained   Type: Original Researc

    Inpatient falls in older adults:a cohort study of antihypertensive prescribing pre- and post-fall

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    Abstract Background Falls are common during hospital admissions and may occur more frequently in patients who are taking antihypertensive medications, particularly in the context of normal to low blood pressure. The review and adjustment of these medications is an essential aspect of the post-fall assessment and should take place as soon as possible after the fall. Our aim was to investigate whether appropriate post-fall adjustments of antihypertensive medications are routinely made in a large National Health Service (NHS) Trust. Methods Inpatient records over an eight-month period were captured from an electronic prescribing system to identify older adults (≥80 years old) with normal/low blood pressures (< 140 mmHg systolic) who had a documented inpatient fall as these patients were considered to be at high risk of further falls. Prescribed antihypertensive medication on admission was then compared with the post-fall (within 24 h after the fall) and discharge prescriptions. Results A total of 146 patients were included in the analysis. Of those, 120 patients (82%) were taking the same number of antihypertensive medications in the 24 h after the fall as they were before; only 19 patients (13%) had a reduction in the number of medications and seven patients (5%) had an increase in medications during that period. Only 9% of the antihypertensive classes assessed were either stopped or reduced in dose immediately post-fall. In addition, 11 new antihypertensives were prescribed at this time. At discharge, half of the patients (n = 73) remained on the same number of antihypertensive medication as on admission, 51 patients (35%) were on fewer antihypertensives and 22 (15%) were on more. Additionally, no changes were made to individual antihypertensives in 49% of prescriptions; 34% were stopped or reduced in dose but 38 new agents were started by the time of discharge. Angiotensin converting enzyme inhibitors and angiotensin II receptor blockers (ACEi/ARB) were the class of medications most commonly stopped or reduced (51%). Conclusions Antihypertensive prescriptions are frequently unchanged after an inpatient fall. Routine medication review needs to be part of post-fall assessments in hospital to reduce the risk of further falls

    Infrared spectroscopy of Nova Cassiopeiae 1993 (V705 Cas). IV. A closer look at the dust

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    Nova Cassiopeiae 1993 (V705 Cas) was an archetypical dust-forming nova. It displayed a deep minimum in the visual light curve, and spectroscopic evidence for carbon, hydrocarbon and silicate dust. We report the results of fitting the infrared spectral energy distribution with the DUSTY code, which we use to determine the properties and geometry of the emitting dust. The emission is well described as originating in a thin shell whose dust has a carbon:silicate ratio of ~2:1 by number (1.26:1 by mass) and a relatively flat size distribution. The 9.7micron and 18micron silicate features are consistent with freshly-condensed dust and, while the lower limit to the grain size distribution is not well constrained, the largest grains have dimensions \~0.06micron; unless the grains in V705 Cas were anomalously small, the sizes of grains produced in nova eruptions may previously have been overestimated in novae with optically thick dust shells. Laboratory work by Grishko & Duley may provide clues to the apparently unique nature of nova UIR features.Comment: 11 pages, 9 fugure

    The potential role of community pharmacy staff in reducing patient delay in consulting with symptoms of rheumatoid arthritis: a qualitative study.

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    BACKGROUND: Rheumatoid arthritis (RA) is a chronic inflammatory arthritis which can cause joint damage and reduced quality of life. Early treatment of RA within 3 months of symptom onset is associated with improved clinical outcomes. However, this window of opportunity is often missed. One important contributing factor is patients with symptoms of RA delaying consulting their general practitioner (GP). Previous research indicates that patients with inflammatory arthritis are likely to visit pharmacies for advice before consulting their GP. Therefore, pharmacists are well positioned to identify patients with symptoms of early inflammatory arthritis and signpost them appropriately. This research examines community pharmacy staff's knowledge, perceptions, and approaches to management of patients presenting with symptoms of RA in order to identify training needs and other opportunities for intervention to enhance the role of pharmacy staff in the pathway to care. METHODS: Semi-structured interviews were conducted with 19 community pharmacy staff in the West Midlands (UK), during a 12-month period (2017-2018). The interviews were audio-recorded, transcribed, and analyzed using thematic analysis facilitated by NVivo 12. RESULTS: There was considerable variation in knowledge and perceptions of RA and the need for early treatment amongst pharmacists and other pharmacy staff. The potential role of pharmacists and other pharmacy staff in reducing delay in help-seeking was also discussed. Four themes emerged from thematic analysis: (1) Variations in perceptions and knowledge about RA. (2) The role of the pharmacy in increasing public awareness about RA. (3) The role of the pharmacy staff in facilitating access to the GP. (4) Practical considerations for pharmacy-based interventions. CONCLUSION: Variability in knowledge and perceptions of RA amongst pharmacists, and amongst other pharmacy staff will affect effective signposting of suspected RA cases. This study identifies opportunities for enhanced training of community pharmacists and other pharmacy staff in relation to inflammatory arthritis as well as other pharmacy-based interventions, such as public awareness campaigns about RA and other musculoskeletal conditions. Together with existing referral services and other pharmacy-based initiatives this could result in enhanced signposting to GP consultation or other appropriate NHS services for inflammatory symptoms and reduced treatment delay

    The potential role of community pharmacy staff in reducing patient delay in consulting with symptoms of rheumatoid arthritis: a qualitative study.

    Get PDF
    BACKGROUND: Rheumatoid arthritis (RA) is a chronic inflammatory arthritis which can cause joint damage and reduced quality of life. Early treatment of RA within 3 months of symptom onset is associated with improved clinical outcomes. However, this window of opportunity is often missed. One important contributing factor is patients with symptoms of RA delaying consulting their general practitioner (GP). Previous research indicates that patients with inflammatory arthritis are likely to visit pharmacies for advice before consulting their GP. Therefore, pharmacists are well positioned to identify patients with symptoms of early inflammatory arthritis and signpost them appropriately. This research examines community pharmacy staff's knowledge, perceptions, and approaches to management of patients presenting with symptoms of RA in order to identify training needs and other opportunities for intervention to enhance the role of pharmacy staff in the pathway to care. METHODS: Semi-structured interviews were conducted with 19 community pharmacy staff in the West Midlands (UK), during a 12-month period (2017-2018). The interviews were audio-recorded, transcribed, and analyzed using thematic analysis facilitated by NVivo 12. RESULTS: There was considerable variation in knowledge and perceptions of RA and the need for early treatment amongst pharmacists and other pharmacy staff. The potential role of pharmacists and other pharmacy staff in reducing delay in help-seeking was also discussed. Four themes emerged from thematic analysis: (1) Variations in perceptions and knowledge about RA. (2) The role of the pharmacy in increasing public awareness about RA. (3) The role of the pharmacy staff in facilitating access to the GP. (4) Practical considerations for pharmacy-based interventions. CONCLUSION: Variability in knowledge and perceptions of RA amongst pharmacists, and amongst other pharmacy staff will affect effective signposting of suspected RA cases. This study identifies opportunities for enhanced training of community pharmacists and other pharmacy staff in relation to inflammatory arthritis as well as other pharmacy-based interventions, such as public awareness campaigns about RA and other musculoskeletal conditions. Together with existing referral services and other pharmacy-based initiatives this could result in enhanced signposting to GP consultation or other appropriate NHS services for inflammatory symptoms and reduced treatment delay

    Probing the circumstellar structure of Herbig Ae/Be stars

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    We present Halpha spectropolarimetry observations of a sample of 23 Herbig Ae/Be stars. A change in the linear polarisation across Halpha is detected in a large fraction of the objects, which indicates that the regions around Herbig stars are flattened (disc-like) on small scales. A second outcome of our study is that the spectropolarimetric signatures for the Ae stars differ from those of the Herbig Be stars, with characteristics changing from depolarisation across Halpha in the Herbig Be stars, to line polarisations in the Ae group. The frequency of depolarisations detected in the Herbig Be stars (7/12) is particularly interesting as, by analogy to classical Be stars, it may be the best evidence to date that the higher mass Herbig stars are surrounded by flattened structures. For the Herbig Ae stars, 9 out of 11 show a line polarisation effect that can be understood in terms of a compact Halpha emission that is itself polarised by a rotating disc-like circumstellar medium. The spectropolarimetric difference between the Herbig Be and Ae stars may be the first indication that there is a transition in the Hertzsprung-Russell Diagram from magnetic accretion at spectral type A to disc accretion at spectral type B. Alternatively, the interior polarised line emission apparent in the Ae stars may be masked in the Herbig Be stars due to their higher levels of Halpha emission.Comment: 14 pages, MNRAS accepte
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