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A common strategy for managing emergency department (ED) patients with low-risk abdominal pain is to discharge them home and arrange for next day outpatient ultrasound for further assessment. The objective was to determine the proportion of outpatient ultrasounds with findings requiring intervention within 14 days.
This was a retrospective chart review of non-pregnant patients ages 18 to 40 years, presenting to an academic ED (annual census 65,000) with an abdominal complaint for whom the emergency physician arranged an outpatient (next day) abdominal ultrasound.
Of the 299 included patients, 252 (84.3%) were female and mean (SD) age was 28.4 (6.0) years. Twenty-three (7.7%) patients had ultrasounds requiring intervention within 14 days of imaging. Of these, eight (34.8%) had appendicitis, five (21.7%) had cholecystitis, four (17.4%) had urological pathology, three (13.0%) had gynecological pathology, and three (13.0%) had gastrointestinal diagnoses. Of note, 14 (60.9%) patients requiring follow-up or intervention within 14 days had symptoms that improved or resolved at the time of the outpatient ultrasound. For the 277 (92.6%) patients not requiring intervention, 117 (42.2%) had improved, 89 (32.1%) were unchanged, 50 (18.1%) had resolved, and 5 (1.8%) had worsened symptoms at the time of the follow-up ultrasound. Of the non-intervention patients, 13 (4.7%) went on to have alternative imaging, including magnetic resonance imaging, computed tomography, and a sonohysterogram.
Next-day ultrasound imaging remains a good way of identifying patients with serious pathology not appreciated at the time of their ED visit.
The unsteady lift response of an airfoil in a sinusoidal gust has in the past been modelled by two different transfer functions: the first-order Sears function and the second-order Atassi function. Previous studies have shown that the Sears function holds in experiments, but recently Cordes et al. (J. Fluid Mech., vol. 811, 2017) reported experimental data that corresponded to the Atassi function rather than the Sears function. In order to clarify the observed discrepancy, the specific differences between these models are isolated analytically. To this end, data and analysis are confined to unloaded airfoils. These differences are related to physical gust parameters, and gusts with these parameters are then produced in wind-tunnel experiments using an active-grid gust generator. Measurements of the unsteady gust loads on an airfoil in the wind tunnel at Reynolds numbers (
and reduced frequencies between
confirm that the Sears and Atassi functions differ only in convention: the additional gust component of the Atassi problem can be scaled so that the Atassi function collapses onto the Sears function. These experiments, complemented by numerical simulations of the set-up, validate both models across a range of gust parameters. Finally, the influence of boundary-layer turbulence and the turbulent wake of the gust generator on experimental convergence with model predictions is investigated. These results serve to clarify the conditions under which the Sears and Atassi functions can be applied, and demonstrate that the Sears function can effectively model unsteady forces even when significant fluctuations in the streamwise velocity are present.
The main risk factor for acquisition of antimicrobial-resistant bacteria (ARB) is antimicrobial exposure, although acquisition can occur in their absence. The aim of this study was to quantify the proportion of patients who acquire ARB without antimicrobial exposure.
We searched Medline, Embase, and the Cochrane library for publications between January 1, 2000, and July 24, 2017, to identify studies of ARB acquisition in endemic settings. Studies required collection of serial surveillance cultures with acquisition defined as a negative baseline culture and a subsequent positive culture for an ARB, including either multidrug-resistant gram-negative bacteria or antimicrobial-resistant enterococci. Intervention studies were excluded. For each study, the proportion of patients who acquired an ARB but were not exposed to antimicrobials during the study period was quantified.
A total of 4,233 citations were identified; 147 underwent full-text review. Of these, 10 studies met inclusion criteria; 7 studies were considered to be at low risk of bias; and 6 studies were conducted in the intensive care unit (ICU) setting. The overall summary estimate for the proportion of patients who were not exposed to antimicrobials among those who acquired an ARB was 16.6% (95% CI, 7.8%–31.8%; P < .001), ranging from 0% to 57.1%. We observed no heterogeneity in the ICU studies but high heterogeneity among the non-ICU studies.
In most included studies, a subset of patients acquired an ARB but were not exposed to antimicrobials. Future studies need to address transmission dynamics of ARB acquisition in the absence of antimicrobials.
We aimed to provide comprehensive estimates of laboratory-confirmed respiratory syncytial virus (RSV)-associated hospitalisations. Between 2012 and 2015, active surveillance of acute respiratory infection (ARI) hospitalisations during winter seasons was used to estimate the seasonal incidence of laboratory-confirmed RSV hospitalisations in children aged <5 years in Auckland, New Zealand (NZ). Incidence rates were estimated by fine age group, ethnicity and socio-economic status (SES) strata. Additionally, RSV disease estimates determined through active surveillance were compared to rates estimated from hospital discharge codes. There were 5309 ARI hospitalisations among children during the study period, of which 3923 (73.9%) were tested for RSV and 1597 (40.7%) were RSV-positive. The seasonal incidence of RSV-associated ARI hospitalisations, once corrected for non-testing, was 6.1 (95% confidence intervals 5.8–6.4) per 1000 children <5 years old. The highest incidence was among children aged <3 months. Being of indigenous Māori or Pacific ethnicity or living in a neighbourhood with low SES independently increased the risk of an RSV-associated hospitalisation. RSV hospital discharge codes had a sensitivity of 71% for identifying laboratory-confirmed RSV cases. RSV infection is a leading cause of hospitalisation among children in NZ, with significant disparities by ethnicity and SES. Our findings highlight the need for effective RSV vaccines and therapies.
Extra-care housing (ECH) has been hailed as a potential solution to some of the problems associated with traditional forms of social care, since it allows older people to live independently, while also having access to care and support if required. However, little longitudinal research has focused on the experiences of residents living in ECH, particularly in recent years. This paper reports on a longitudinal study of four ECH schemes in the United Kingdom. Older residents living in ECH were interviewed four times over a two-year period to examine how changes in their care needs were encountered and negotiated by care workers, managers and residents themselves. This paper focuses on how residents managed their own changing care needs within the context of ECH. Drawing upon theories of the third and fourth age, the paper makes two arguments. First, that transitions across the boundary between the third and fourth age are not always straightforward or irreversible and, moreover, can sometimes be resisted, planned-for and managed by older people. Second, that operational practices within ECH schemes can function to facilitate or impede residents’ attempts to manage this boundary.
Rows upon rows of “virtual stacks” now stretch as far as the eye can see. From JSTOR to the Library of Congress to Ancestry.com, unprecedented quantities of historical material are being added to the digital ether. In fact, you are probably reading these words on a screen right now. Search-box interfaces allow historians to instantly query vast quantities of historical material in order to pull out information about individuals, events, institutions, and locations. With just a few strokes of a keyboard, a historian can sift through millions of digitized pages of newspapers, government documents, or books. A process that would have once taken a lifetime of flipping through microfilm or archival folders can be conducted in just a few minutes. As historian Lara Putnam notes, this now “feels as revolutionary as oatmeal.” But, she argues, the “mass digitized turn” has nevertheless had a profound impact on the practice of history in ways that the discipline is only beginning to understand. This is especially true for a field like modern American history, where an abundance of easily scannable English-language sources has generated a wealth of online material.
The use of spatial econometric models in political science has steadily risen in recent years. However, the interpretation of these models has generally ignored the important substantive, and even spatial, nature of the estimated effects. This leaves many papers with a (non-spatial) interpretation of coefficients on the covariates and a brief discussion of the sign and strength of the spatial parameter. We introduce a general approach to interpreting spatial models and provide several avenues for an exposition of substantive spatial effects. Our approach can be generalized to most models in the spatial econometric taxonomy. Building on the example of the diffusion of democracy, we elucidate how our approach can be applied to modern political science problems.
A theoretically based relationship for the Darcy–Weisbach friction factor
for rough-bed open-channel flows is derived and discussed. The derivation procedure is based on the double averaging (in time and space) of the Navier–Stokes equation followed by repeated integration across the flow. The obtained relationship explicitly shows that the friction factor can be split into at least five additive components, due to: (i) viscous stress; (ii) turbulent stress; (iii) dispersive stress (which in turn can be subdivided into two parts, due to bed roughness and secondary currents); (iv) flow unsteadiness and non-uniformity; and (v) spatial heterogeneity of fluid stresses in a bed-parallel plane. These constitutive components account for the roughness geometry effect and highlight the significance of the turbulent and dispersive stresses in the near-bed region where their values are largest. To explore the potential of the proposed relationship, an extensive data set has been assembled by employing specially designed large-eddy simulations and laboratory experiments for a wide range of Reynolds numbers. Flows over self-affine rough boundaries, which are representative of natural and man-made surfaces, are considered. The data analysis focuses on the effects of roughness geometry (i.e. spectral slope in the bed elevation spectra), relative submergence of roughness elements and flow and roughness Reynolds numbers, all of which are found to be substantial. It is revealed that at sufficiently high Reynolds numbers the roughness-induced and secondary-currents-induced dispersive stresses may play significant roles in generating bed friction, complementing the dominant turbulent stress contribution.