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Introduction: Although use of point of care ultrasound (PoCUS) protocols for patients with undifferentiated hypotension in the Emergency Department (ED) is widespread, our previously reported SHoC-ED study showed no clear survival or length of stay benefit for patients assessed with PoCUS. In this analysis, we examine if the use of PoCUS changed fluid administration and rates of other emergency interventions between patients with different shock types. The primary comparison was between cardiogenic and non-cardiogenic shock types. Methods: A post-hoc analysis was completed on the database from an RCT of 273 patients who presented to the ED with undifferentiated hypotension (SBP <100 or shock index > 1) and who had been randomized to receive standard care with or without PoCUS in 6 centres in Canada and South Africa. PoCUS-trained physicians performed scans after initial assessment. Shock categories and diagnoses recorded at 60 minutes after ED presentation, were used to allocate patients into subcategories of shock for analysis of treatment. We analyzed actual care delivered including initial IV fluid bolus volumes (mL), rates of inotrope use and major procedures. Standard statistical tests were employed. Sample size was powered at 0.80 (α:0.05) for a moderate difference. Results: Although there were expected differences in the mean fluid bolus volume between patients with non-cardiogenic and cardiogenic shock, there was no difference in fluid bolus volume between the control and PoCUS groups (non-cardiogenic control 1878 mL (95% CI 1550 – 2206 mL) vs. non-cardiogenic PoCUS 1687 mL (1458 – 1916 mL); and cardiogenic control 768 mL (194 – 1341 mL) vs. cardiogenic PoCUS 981 mL (341 – 1620 mL). Likewise there were no differences in rates of inotrope administration, or major procedures for any of the subcategories of shock between the control group and PoCUS group patients. The most common subcategory of shock was distributive. Conclusion: Despite differences in care delivered by subcategory of shock, we did not find any significant difference in actual care delivered between patients who were examined using PoCUS and those who were not. This may help to explain the previously reported lack of outcome difference between groups.
Introduction: Point of care ultrasound has been reported to improve diagnosis in non-traumatic hypotensive ED patients. We compared diagnostic performance of physicians with and without PoCUS in undifferentiated hypotensive patients as part of an international prospective randomized controlled study. The primary outcome was diagnostic performance of PoCUS for cardiogenic vs. non-cardiogenic shock. Methods: SHoC-ED recruited hypotensive patients (SBP < 100 mmHg or shock index > 1) in 6 centres in Canada and South Africa. We describe previously unreported secondary outcomes relating to diagnostic accuracy. Patients were randomized to standard clinical assessment (No PoCUS) or PoCUS groups. PoCUS-trained physicians performed scans after initial assessment. Demographics, clinical details and findings were collected prospectively. Initial and secondary diagnoses including shock category were recorded at 0 and 60 minutes. Final diagnosis was determined by independent blinded chart review. Standard statistical tests were employed. Sample size was powered at 0.80 (α:0.05) for a moderate difference. Results: 273 patients were enrolled with follow-up for primary outcome completed for 270. Baseline demographics and perceived category of shock were similar between groups. 11% of patients were determined to have cardiogenic shock. PoCUS had a sensitivity of 80.0% (95% CI 54.8 to 93.0%), specificity 95.5% (90.0 to 98.1%), LR+ve 17.9 (7.34 to 43.8), LR-ve 0.21 (0.08 to 0.58), Diagnostic OR 85.6 (18.2 to 403.6) and accuracy 93.7% (88.0 to 97.2%) for cardiogenic shock. Standard assessment without PoCUS had a sensitivity of 91.7% (64.6 to 98.5%), specificity 93.8% (87.8 to 97.0%), LR+ve 14.8 (7.1 to 30.9), LR- of 0.09 (0.01 to 0.58), Diagnostic OR 166.6 (18.7 to 1481) and accuracy of 93.6% (87.8 to 97.2%). There was no significant difference in sensitivity (-11.7% (-37.8 to 18.3%)) or specificity (1.73% (-4.67 to 8.29%)). Diagnostic performance was also similar between other shock subcategories. Conclusion: As reported in other studies, PoCUS based assessment performed well diagnostically in undifferentiated hypotensive patients, especially as a rule-in test. However performance was similar to standard (non-PoCUS) assessment, which was excellent in this study.
A compact X-ray energy spectrometer has been developed consisting essentially of a radioisotope X-ray source, a lithium-drifted silicon (or germanium) detector and a small computer. Interchangeable sources enable efficient excitation of K X-rays from Na to U and L X-rays from about Ag to U. Energy resolution of K X-rays from adjacent elements down to Na is possible. Depending on the source and the part of the spectrum examined, the characteristic X-rays from up to about 15 elements can be simultaneously excited and measured, for either qualitative or quantitative multi-element analysis. The computer stores detected spectra and performs simple data processing such as peak recognition, background subtraction, peak integration, ratioing and solution of linear equations.
The analysis reported in this paper is the determination of V, Cr, Fe, Co, W and Mo in tool steels and is intended to illustrate the capabilities of the radioisotope X-ray fluorescence analysis technique, and the instrument, for multi-element analysis of a system having fairly complex interelement effects.
A 100 mCi Pu-238 source was used to excite the K X-rays of V, Cr, Fe, Co and Mb and the L X-rays of W. The count time used was five minutes per sample. Data reduction consisted essentially of peak integration, background subtraction and solution of sixth order linear matrices of a modified Criss-Birks type. The 36 matrix coefficients were determined using six standards, and were then used to analyze seven other analyzed specimens which were treated as unknowns. The measured values of concentration were in very good agreement with the quoted values. An iteration technique was employed to reduce errors in the matrix inversioiis.
Intravenous dextrose aids in the resolution of ketosis in dehydrated patients not tolerating oral glucose and is often recommended in this clinical scenario. Our aim was to determine whether the addition of dextrose to intravenous rehydration solutions results in decreased hospital admissions or other clinically important benefits among dehydrated children or adults.
MEDLINE, EMBASE, Web of Science, SCOPUS, and the Cochrane Library were searched by a medical librarian from inception through November 2017. The inclusion criteria were randomized controlled trials comparing dextrose containing intravenous solutions with intravenous solutions without dextrose in patients being treated for dehydration, and not already hospitalized.
The database and bibliographies search identified 1,472 unique citations. Only two trials (N = 333) met the inclusion criteria. Both compared normal saline with solutions of dextrose in normal saline. There was no statistically significant difference in admission rates (relative risk = 0.83; 95% confidence interval = 0.62 to 1.10) or revisits (relative risk = 0.54; 95% confidence interval = 0.24 to 1.22). Heterogeneity was low (I2 = 0). No other outcome results were eligible for pooling, but neither study found differences in any clinical outcomes. No adverse events were reported in either trial.
The addition of dextrose to intravenous saline has not been shown to improve clinical outcomes in dehydrated children presenting to the emergency department with gastroenteritis, but the confidence intervals around the estimate of effect are wide and include the possibility of substantial benefit.
This contribution discusses results obtained from 3-D neutron diffraction and 2-D fabric analyser in situ deformation experiments on laboratory-prepared polycrystalline deuterated ice and ice containing a second phase. The two-phase samples used in the experiments are composed of an ice matrix with (1) air bubbles, (2) rigid, rhombohedral-shaped calcite and (3) rheologically soft, platy graphite. Samples were tested at 10°C below the melting point of deuterated ice at ambient pressures, and two strain rates of 1 × 10−5 s−1 (fast) and 2.5 × 10−6 s−1 (medium). Nature and distribution of the second phase controlled the rheological behaviour of the ice by pinning grain boundary migration. Peak stresses increased with the presence of second-phase particles and during fast strain rate cycles. Ice-only samples exhibit well-developed crystallographic preferred orientations (CPOs) and dynamically recrystallized microstructures, typifying deformation via dislocation creep, where the CPO intensity is influenced in part by the strain rate. CPOs are accompanied by a concentration of [c]-axes in cones about the compression axis, coinciding with increasing activity of prismatic-<a> slip activity. Ice with second phases, deformed in a relatively slower strain rate regime, exhibit greater grain boundary migration and stronger CPO intensities than samples deformed at higher strain rates or strain rate cycles.
Laser-based compact MeV X-ray sources are useful for a variety of applications such as radiography and active interrogation of nuclear materials. MeV X rays are typically generated by impinging the intense laser onto ~mm-thick high-Z foil. Here, we have characterized such a MeV X-ray source from 120 TW (80 J, 650 fs) laser interaction with a 1 mm-thick tantalum foil. Our measurements show X-ray temperature of 2.5 MeV, flux of 3 × 1012 photons/sr/shot, beam divergence of ~0.1 sr, conversion efficiency of ~1%, that is, ~1 J of MeV X rays out of 80 J incident laser, and source size of 80 m. Our measurement also shows that MeV X-ray yield and temperature is largely insensitive to nanosecond laser contrasts up to 10−5. Also, preliminary measurements of similar MeV X-ray source using a double-foil scheme, where the laser-driven hot electrons from a thin foil undergoing relativistic transparency impinging onto a second high-Z converter foil separated by 50–400 m, show MeV X-ray yield more than an order of magnitude lower compared with the single-foil results.
OBJECTIVES/SPECIFIC AIMS: Listening effort is needed to understand speech that is degraded by hearing loss and/or a noisy environment. Effortful listening reduces cognitive spare capacity (CSC). Predictive contexts aid speech perception accuracy, but it is not known whether the use of context reduces or preserves CSC. Here, we compare the impact of predictive context and cognitive load on behavioral indices of CSC in elderly, hearing-impaired adults. METHODS/STUDY POPULATION: Elderly, hearing-impaired adults listened in a noisy background to spoken sentences in which sentence-final words were either predictable or not predictable based on the sentence context. Cognitive load was manipulated by asking participants to remember either short or long sequences of visually presented digits. Participants were divided into low or high cognitive capacity groups based on a pretest of working memory. Accuracy and response times were examined for report of both sentence-final words and digit sequences. RESULTS/ANTICIPATED RESULTS: Preliminary results indicate that accuracy and response times for both words and digits were facilitated by sentence predictability, suggesting that the use of predictive sentence context preserves CSC. Response times for both words and digits and accuracy for digits were impaired under cognitive load. Trends were similar across high and low cognitive capacity groups. The preliminary results support the idea that habilitation strategies involving context use could potentially support CSC in elderly, hearing-impaired adults. DISCUSSION/SIGNIFICANCE OF IMPACT: These preliminary results support the concept that habilitation strategies involving context use could potentially support CSC in elderly, hearing-impaired adults.
Following large declines in tuberculosis transmission the United States, large-scale screening programs targeting low-risk healthcare workers are increasingly a source of false-positive results. We report a large cluster of presumed false-positive tuberculin skin test results in healthcare workers following a change to 50-dose vials of Tubersol tuberculin.
Although the need for pigs to lie down on long journeys is not in question, there is evidence that they may not choose to do so on journeys of less than 3h (Hunter et al., 1994). These observations were undertaken to determine how pigs in the 95 to 100 kg weight range behaved on short journeys. A three-tier floating-deck vehicle with weld-mesh flooring was used because the popularity of three-deck vehicles is increasing (Riches et al., 1996).
Whilst many of the on-farm factors identified as enhancing pigmeat meat eating quality are already standard commercial practice, variability in quality is still a problem whose reasons are poorly understood. Particular uncertainty exists about the effect on eating quality of increasing slaughter weight, a current development which facilitates reduced cost of production by spreading carcass overhead costs between more kg of saleable meat. However, this strategy means that pigs will be older at slaughter, which carries uncertainties about the risk of increased toughness and boar taint. In targeting a market for branded pigmeat of high eating quality, there may also be beneficial strategies for adoption in carcass selection and post-slaughter management. These questions were addressed as part of a research project on the improvement of meat eating quality in the Scottish red meat sector.
There are many studies that show that breed, gender, age and feeding regime influence animal growth rate, meat yield and composition. These factors, together with slaughter and post-slaughter conditions, are thought to influence tenderness and flavour attributes of meat (Thompson, 2002)). Low variability is highly desirable and processes such as ‘A blueprint for improved consistent quality lamb’ (MLC, 1999) in the UK have attempted to improve the level and consistency of lamb eating quality. The purpose of this trial was to test whether the adoption of several key enhanced on–farm and in-abattoir practices led to improved eating quality throughout the lamb production season, especially for heavier, lean carcasses.
Milk progesterone monitoring in dairy cattle has provided a valuable insight into the reproductive cycle during the post-partum and mating periods (Lamming et al., 1981; Darwash and Lamming, 1997). In this study a similar approach was applied to suckler cows. The objective was to compare the reproductive performance of two contrasting genotypes with a view to improving output from commercial herds. Such herds produce an average of 91 live calves per 100 cows mated (MLC, 1996).
There are many studies that show that breed, gender, age and feeding regime influence animal growth rate, meat yield and composition. These factors, together with slaughter and post-slaughter conditions, are thought to influence tenderness and flavour attributes of meat (Thompson, 2002)). Low variability is highly desirable and processes such as ‘A blueprint for improved consistent quality beef’ (MLC, 1999) in the UK has attempted to improve the level and consistency of beef eating quality. This project was designed to test a package of best-practice techniques, both on-farm and in-abattoir, on the eating quality of Scottish beef as assessed by a trained sensory panel and a recruited take-home panel.
Reproductive failure is a source of major economic loss to the UK pig industry, accounting for 0.5 of all first parity gilt cullings (MLC Pig Year Book, 1995). Previous research (Cameron et al, 1999) has shown that rearing gilts on a diet formulated to support maximal protein deposition has beneficial effects on ovulation rate at 3rd oestrus. The aim of the current experiment was to develop further the previous model to assess long and short-term effects of protein nutrition on reproductive performance, body composition and metabolic status.
Recent MLC survey data (Pig Year Book, 1995) reports that approximately 0.5 of annual first parity gilt cullings are due to reproductive failure. This high culling rate may be attributed to recent genetic selection for increased lean tissue accretion rates, and as a result a greater mature body weight. However, the gilt attains puberty and is thus mated at a lower age and as a consequence has not reached the target threshold of 35kg body protein mass at farrowing, suggested by Everts (1994),to be necessary for optimal reproductive performance. This, confounded with excessive tissue catabolism over lactation results in the attenuation of the gilt's potential protein accretion curve and hence reproductive failure (Foxcroft et al. 1995). The aim of this experiment was to study the effect of two protein accretion rates (maximum and 0.8 of maximum) on reproductive function in the gilt from 50kg liveweight to 3rd oestrus.
Taking as a premise that phonological working memory (PWM) influences later language development, in their keynote article, Pierce, Genesee, Delcenserie, and Morgan aim to specify the relations between early language input and the development of PWM in terms of separable influences of timing, quantity, and quality of early language input. We concur that prior work has established that PWM and language development have reciprocal influences on one another during development (e.g., Baddeley, Gathercole, & Papagno, 1998; Gathercole, 2006; Gathercole, Hitch, Service, & Martin, 1997; Metsala & Chisolm, 2010). The goal of the keynote article was to describe how early language experience may influence the development of PWM. Pierce et al. argue that this can be done by comparing the development of PWM across groups of children with differing language experiences during early childhood, specifically (a) delayed exposure to language, (b) impoverished language input, or (c) enriched language input. The authors suggest that this comparison may contribute to establishing that individual differences in PWM are due, in part, to early language experience. Sensitive periods for phonological development that are open roughly in the first year of life are discussed, and it is suggested that the quantity and quality of early language input shapes the quality of phonological representations. Efforts to specify mechanisms by which early language input may influence the development of PWM have both theoretical and, potentially, clinical importance. Considering this, Pierce et al.’s article, which aims to create a platform for future research in terms of the timing, quantity, and quality of early language input, is a valuable contribution.
Observations of the water level in Beaver Lake, an epishelf lake in East Antarctica, show a regular tidal signal that is lagged and attenuated from the tides beneath the adjacent Amery Ice Shelf. The phase lag and amplitude attenuation can be created by a narrow inlet connection between Beaver Lake and the cavity beneath the Amery Ice Shelf. A forced linear damped oscillator is used to determine the inlet dimensions that are required to produce the observed phase lag and amplitude attenuation. The model shows that the observations are consistent with a tidal flow that is restricted by the drag created by flow in the narrow inlet. Analysis shows that the phase lag and amplitude attenuation of the tides in Beaver Lake has increased over the years 1991-2002, probably due to a thickening of the overlying ice shelf. The response is sensitive to subtle variations in the dimensions of the inlet.