2,234 research outputs found

    An experimental and computational analysis of buoyancy driven flows by laser sheet tomography, particle image velocimetry and computational fluid dynamics

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    This paper contains details of a three pronged investigation into the development of a buoyant jet impinging on a wall in a closed vessel. The development of the flow was measured experimentally by particle image velocimetry (PIV) and laser sheet tomography. The experimental results are compared with a computational model of the flow calculated by the computational fluid dynamics (CFD) package PHOENICS

    Meteoritic Material Recovered from the 07 March 2018 Meteorite Fall into the Olympic Coast National Marine Sanctuary

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    On 07 March 2018 at 20:05 local time (08 March 03:05 UTC), a dramatic meteor occurred over Olympic Coast National Marine Sanctuary (OCNMS) off of the Washington state coast (OCNMS fall, henceforth). Data to include seismometry (from both on-shore and submarine seismometers), weather radar imagery (Figure 1), and a moored weather buoy, were used to accurately identify the fall site. The site was visited by the exploration vessel E/V Nautilus (Ocean Exploration Trust) on 01 July 2018 [1] and by the research vessel R/V Falkor (Schmidt Ocean Institute) from 03-06 June 2019. Remotely operated vehicles (ROVs) from both vessels were used to search for meteorites and sample seafloor sediments. These expeditions performed the first attempts to recover meteorites from a specific observed fall in the open ocean. Analysis of weather radar data indicates that this fall was unusually massive and featured meteorites of unusually high mechanical toughness, such that large meteorites were disproportionately produced compared to other meteorite falls (Figure 2)[2-4]. We report the recovery of many (>100) micrometeorite-sized melt spherules and other fragments, and one small (~1mm3 ) unmelted meteorite fragment identified to date. Approximately 80% of the fragments were recovered from a single sample, collected from a round pit in the seafloor sediment. Melt spherules are almost exclusively type I iron-rich spherules with little discernible oxidation. Analyses are currently underway to attempt to answer the primary science question by identifying the parent meteorite type. Also, differences in the number and nature of samples collected by Nautilus and Falkor reveal a distinct loss rate to oxidation over the 15 months following the fall that is useful to inform future recovery efforts

    Editorial

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    Editorial by Dr. James F. Waddel

    Pharmacological and conservative interventions for ear discharge associated with grommets (ventilation tubes) outside the postoperative period

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    This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the effectiveness and safety of various treatment strategies in patients with grommets who developed ear discharge

    The influence of 'significant others' on persistent back pain and work participation: a qualitative exploration of illness perceptions

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    Background Individual illness perceptions have been highlighted as important influences on clinical outcomes for back pain. However, the illness perceptions of 'significant others' (spouse/partner/close family member) are rarely explored, particularly in relation to persistent back pain and work participation. The aim of this study was to initiate qualitative research in this area in order to further understand these wider influences on outcome. Methods Semi-structured interviews based on the chronic pain version of the Illness Perceptions Questionnaire-Revised were conducted with a convenience sample of UK disability benefit claimants, along with their significant others (n=5 dyads). Data were analysed using template analysis. Results Significant others shared, and perhaps further reinforced, claimants' unhelpful illness beliefs including fear of pain/re-injury associated with certain types of work and activity, and pessimism about the likelihood of return to work. In some cases, significant others appeared more resigned to the permanence and negative inevitable consequences of the claimant's back pain condition on work participation, and were more sceptical about the availability of suitable work and sympathy from employers. In their pursuit of authenticity, claimants were keen to stress their desire to work whilst emphasising how the severity and physical limitations of their condition prevented them from doing so. In this vein, and seemingly based on their perceptions of what makes a 'good' significant other, significant others acted as a 'witness to pain', supporting claimants' self-limiting behaviour and statements of incapacity, often responding with empathy and assistance. The beliefs and responses of significant others may also have been influenced by their own experience of chronic illness, thus participants lives were often intertwined and defined by illness. Conclusions The findings from this exploratory study reveal how others and wider social circumstances might contribute both to the propensity of persistent back pain and to its consequences. This is an area that has received little attention to date, and wider support of these findings may usefully inform the design of future intervention programmes aimed at restoring work participation

    Interventions for children with ear discharge occurring at least two weeks following grommet (ventilation tube) insertion

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    BACKGROUND: Ear discharge (otorrhoea) is common in children with grommets (ventilation/tympanostomy tubes); the proportion of children developing discharge ranges from 25% to 75%. The most common treatment strategies include oral broad-spectrum antibiotics, antibiotic eardrops or those containing a combination of antibiotic(s) and a corticosteroid, and initial observation. Important drivers for one strategy over the other are concerns over the side effects of oral antibiotics and the potential ototoxicity of antibiotic eardrops. OBJECTIVES: To assess the benefits and harms of current treatment strategies for children with ear discharge occurring at least two weeks following grommet (ventilation tube) insertion. SEARCH METHODS: The Cochrane ENT Information Specialist searched the ENT Trials Register, CENTRAL (2016, Issue 5), multiple databases and additional sources for published and unpublished trials (search date 23 June 2016). SELECTION CRITERIA: Randomised controlled trials comparing at least two of the following: oral antibiotics, oral corticosteroids, antibiotic eardrops (with or without corticosteroid), corticosteroid eardrops, microsuction cleaning of the ear canal, saline rinsing of the ear canal, placebo or no treatment. The main comparison of interest was antibiotic eardrops (with or without corticosteroid) versus oral antibiotics. DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures expected by Cochrane. Primary outcomes were: proportion of children with resolution of ear discharge at short-term follow-up (less than two weeks), adverse events and serious complications. Secondary outcomes were: proportion of children with resolution of ear discharge at intermediate- (two to four weeks) and long-term (four to 12 weeks) follow-up, proportion of children with resolution of ear pain and fever at short-term follow-up, duration of ear discharge, proportion of children with chronic ear discharge, ear discharge recurrences, tube blockage, tube extrusion, health-related quality of life and hearing. We used GRADE to assess the quality of the evidence for each outcome; this is indicated in italics. MAIN RESULTS: We included nine studies, evaluating a range of treatments, with 2132 children who developed acute ear discharge beyond the immediate postoperative period. We judged the risk of bias to be low to moderate in most studies. Antibiotic eardrops (with or without corticosteroid) versus oral antibioticsAntibiotic eardrops with or without corticosteroid were more effective than oral antibiotics in terms of:- resolution of discharge at one week (one study, 42 children, ciprofloxacin eardrops versus amoxicillin: 77% versus 30%; risk ratio (RR) 2.58, 95% confidence interval (CI) 1.27 to 5.22; moderate-quality evidence);- resolution of discharge at two weeks (one study, 153 children, bacitracin-colistin-hydrocortisone eardrops versus amoxicillin-clavulanate: 95% versus 56%; RR 1.70, 95% CI 1.38 to 2.08; moderate-quality evidence);- duration of discharge (two studies, 233 children, ciprofloxacin eardrops versus amoxicillin: median 4 days versus 7 days and bacitracin-colistin-hydrocortisone eardrops versus amoxicillin-clavulanate: 4 days versus 5 days; moderate-quality evidence);- ear discharge recurrences (one study, 148 children, bacitracin-colistin-hydrocortisone eardrops versus amoxicillin-clavulanate: 0 versus 1 episode at six months; low-quality evidence); and- disease-specific quality of life (one study, 153 children, bacitracin-colistin-hydrocortisone eardrops versus amoxicillin-clavulanate: difference in change in median Otitis Media-6 total score (range 6 to 42) at two weeks: -2; low-quality evidence).We found no evidence that antibiotic eardrops were more effective in terms of the proportion of children developing chronic ear discharge or tube blockage, generic quality of life or hearing.Adverse events occurred at similar rates in children treated with antibiotic eardrops and those treated with oral antibiotics, while no serious complications occurred in either of the groups. Other comparisons(a) Antibiotic eardrops with or without corticosteroid were more effective thancorticosteroid eardrops in terms of:- duration of ear discharge (one study, 331 children, ciprofloxacin versus ciprofloxacin-fluocinolone acetonide versus fluocinolone acetonide eardrops: median 5 days versus 7 days versus 22 days; moderate-quality evidence).(b) Antibiotic eardrops were more effective than saline rinsing of the ear canal in terms of:- resolution of ear discharge at one week (one study, 48 children, ciprofloxacin eardrops versus saline rinsing: 77% versus 46%; RR 1.67, 95% CI 1.04 to 2.69; moderate-quality evidence);but not in terms of tube blockage. Since the lower limit of the 95% CI for the effect size for resolution of ear discharge at one week approaches unity, a trivial or clinically irrelevant difference cannot be excluded.(c) Eardrops containing two antibiotics and a corticosteroid (bacitracin-colistin-hydrocortisone) were more effective than no treatment in terms of:- resolution of discharge at two weeks (one study; 151 children: 95% versus 45%; RR 2.09, 95% CI 1.62 to 2.69; moderate-quality evidence);- duration of discharge (one study; 147 children, median 4 days versus 12 days; moderate-quality evidence);- chronic discharge (one study; 147 children; RR 0.08, 95% CI 0.01 to 0.62; low-quality evidence); and- disease-specific quality of life (one study, 153 children, difference in change in median Otitis Media-6 total score (range 6 to 42) between groups at two weeks: -1.5; low-quality evidence).We found no evidence that antibiotic eardrops were more effective in terms of ear discharge recurrences or generic quality of life.(d) Eardrops containing a combination of an antibiotic and a corticosteroid were more effective than eardrops containing antibiotics (low-quality evidence) in terms of:- resolution of ear discharge at short-term follow-up (two studies, 590 children: 35% versus 20%; RR 1.76, 95% CI 1.33 to 2.31); and- duration of discharge (three studies, 813 children);but not in terms of resolution of discharge at intermediate-term follow-up or proportion of children with tube blockage. However, there is a substantial risk of publication bias, therefore these findings should be interpreted with caution. AUTHORS' CONCLUSIONS: We found moderate to low-quality evidence that antibiotic eardrops (with or without corticosteroid) are more effective than oral antibiotics, corticosteroid eardrops and no treatment in children with ear discharge occurring at least two weeks following grommet insertion. There is some limited, inconclusive evidence that antibiotic eardrops are more effective than saline rinsing. There is uncertainty whether antibiotic-corticosteroid eardrops are more effective than eardrops containing antibiotics only

    Basis for Treatment of Tuberculosis among HIV-Infected Patients in Tanzania: The Role of Chest X-Ray and Sputum Culture

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    Active tuberculosis (TB) is common among HIV-infected persons living in tuberculosis endemic countries, and screening for tuberculosis (TB) is recommended routinely. We sought to determine the role of chest x-ray and sputum culture in the decision to treat for presumptive TB using active case finding in a large cohort of HIV-infected patients. Ambulatory HIV-positive subjects with CD4 counts ≄ 200/mm3 entering a Phase III TB vaccine study in Tanzania were screened for TB with a physical examination, standard interview, CD4 count, chest x-ray (CXR), blood culture for TB, and three sputum samples for acid fast bacillus (AFB) smear and culture
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