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Emergency Medical Services (EMS) systems have developed protocols for prehospital activation of the cardiac catheterization laboratory for patients with suspected ST-elevation myocardial infarction (STEMI) to decrease first-medical-contact-to-balloon time (FMC2B). The rate of “false positive” prehospital activations is high. In order to decrease this rate and expedite care for patients with true STEMI, the American Heart Association (AHA; Dallas, Texas USA) developed the Mission Lifeline PreAct STEMI algorithm, which was implemented in Los Angeles County (LAC; California USA) in 2015. The hypothesis of this study was that implementation of the PreAct algorithm would increase the positive predictive value (PPV) of prehospital activation.
This is an observational pre-/post-study of the effect of the implementation of the PreAct algorithm for patients with suspected STEMI transported to one of five STEMI Receiving Centers (SRCs) within the LAC Regional System. The primary outcome was the PPV of cardiac catheterization laboratory activation for percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG). The secondary outcome was FMC2B.
A total of 1,877 patients were analyzed for the primary outcome in the pre-intervention period and 405 patients in the post-intervention period. There was an overall decrease in cardiac catheterization laboratory activations, from 67% in the pre-intervention period to 49% in the post-intervention period (95% CI for the difference, -14% to -22%). The overall rate of cardiac catheterization declined in post-intervention period as compared the pre-intervention period, from 34% to 30% (95% CI, for the difference -7.6% to 0.4%), but actually increased for subjects who had activation (48% versus 58%; 95% CI, 4.6%-15.0%). Implementation of the PreAct algorithm was associated with an increase in the PPV of activation for PCI or CABG from 37.9% to 48.6%. The overall odds ratio (OR) associated with the intervention was 1.4 (95% CI, 1.1-1.8). The effect of the intervention was to decrease variability between medical centers. There was no associated change in average FMC2B.
The implementation of the PreAct algorithm in the LAC EMS system was associated with an overall increase in the PPV of cardiac catheterization laboratory activation.
Introduction: Patients presenting to the emergency department (ED) with hypotension have a high mortality rate and require careful yet rapid resuscitation. The use of cardiac point of care ultrasound (PoCUS) in the ED has progressed beyond the basic indications of detecting pericardial fluid and activity in cardiac arrest. We examine if finding left ventricular dysfunction (LVD) on emergency physician performed PoCUS reliably predicts the presence of cardiogenic shock in hypotensive ED patients. Methods: We prospectively collected PoCUS findings performed in 135 ED patients with undifferentiated hypotension as part of an international study. Patients with clearly identified etiologies for hypotension were excluded, along with other specific presumptive diagnoses. LVD was defined as identification of a generally hypodynamic LV in the setting of shock. PoCUS findings were collected using a standardized protocol and data collection form. All scans were performed by PoCUS-trained emergency physicians. Final shock type was defined as cardiogenic or non-cardiogenic by independent specialist blinded chart review. Results: All 135 patients had complete follow up. Median age was 56 years, 53% of patients were male. Disease prevalence for cardiogenic shock was 12% and the mortality rate was 24%. The presence of LVD on PoCUS had a sensitivity of 62.50% (95%CI 35.43% to 84.80%), specificity of 94.12% (88.26% to 97.60%), positive-LR 10.62 (4.71 to 23.95), negative-LR 0.40 (0.21 to 0.75) and accuracy of 90.37% (84.10% to 94.77%) for detecting cardiogenic shock. Conclusion: Detecting left ventricular dysfunction on PoCUS in the ED may be useful in confirming the underlying shock type as cardiogenic in otherwise undifferentiated hypotensive patients.
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.
The effect of transportation and lairage on the faecal shedding and post-slaughter contamination of carcasses with Escherichia coli O157 and O26 in young calves (4–7-day-old) was assessed in a cohort study at a regional calf-processing plant in the North Island of New Zealand, following 60 calves as cohorts from six dairy farms to slaughter. Multiple samples from each animal at pre-slaughter (recto-anal mucosal swab) and carcass at post-slaughter (sponge swab) were collected and screened using real-time PCR and culture isolation methods for the presence of E. coli O157 and O26 (Shiga toxin-producing E. coli (STEC) and non-STEC). Genotype analysis of E. coli O157 and O26 isolates provided little evidence of faecal–oral transmission of infection between calves during transportation and lairage. Increased cross-contamination of hides and carcasses with E. coli O157 and O26 between co-transported calves was confirmed at pre-hide removal and post-evisceration stages but not at pre-boning (at the end of dressing prior to chilling), indicating that good hygiene practices and application of an approved intervention effectively controlled carcass contamination. This study was the first of its kind to assess the impact of transportation and lairage on the faecal carriage and post-harvest contamination of carcasses with E. coli O157 and O26 in very young calves.
Paranoia is one of the commonest symptoms of psychosis but has rarely been studied in a population at risk of developing psychosis. Based on existing theoretical models, including the proposed distinction between ‘poor me’ and ‘bad me’ paranoia, we aimed to test specific predictions about associations between negative cognition, metacognitive beliefs and negative emotions and paranoid ideation and the belief that persecution is deserved (deservedness).
We used data from 117 participants from the Early Detection and Intervention Evaluation for people at risk of psychosis (EDIE-2) trial of cognitive–behaviour therapy, comparing them with samples of psychiatric in-patients and healthy students from a previous study. Multi-level modelling was utilized to examine predictors of both paranoia and deservedness, with post-hoc planned comparisons conducted to test whether person-level predictor variables were associated differentially with paranoia or with deservedness.
Our sample of at-risk mental state participants was not as paranoid, but reported higher levels of ‘bad-me’ deservedness, compared with psychiatric in-patients. We found several predictors of paranoia and deservedness. Negative beliefs about self were related to deservedness but not paranoia, whereas negative beliefs about others were positively related to paranoia but negatively with deservedness. Both depression and negative metacognitive beliefs about paranoid thinking were specifically related to paranoia but not deservedness.
This study provides evidence for the role of negative cognition, metacognition and negative affect in the development of paranoid beliefs, which has implications for psychological interventions and our understanding of psychosis.
Steve Hindle, Foundation Director of Research at the Huntington Library, San Marino, California,Alexandra Shepard, Reader in History, University of Glasgow,John Walter, Professor of History, University of Essex
Samuel Payne was baptised in the mid-Essex village of Terling on 1 August 1736, the fifth child of Robert and Mary Payne. After marrying in 1757 or 1758, he and his wife Sarah went on to have twelve children between 1759 and 1778, including (remarkably) three sets of twins: Hannah and Mary, baptised in June 1768, Joseph and John, baptised in June 1770, and Rhoda and Amelia, baptised in August 1773. This exceptional fertility left the Paynes heavily dependent on relief from the parish throughout the period. Samuel received relief during bouts of ‘sickness’ in each winter between 1767 and 1771, in the summer of 1773, the spring of 1776, and the late summer of 1781. Similarly, Sarah was incapacitated by her repeated pregnancies, requiring assistance in 1766, 1768, from March to December 1770, 1772 and 1773, and the summers of 1776 and 1778, coinciding with the birth of her last two children. By the time Samuel died, aged fifty-two, in January 1789, only nine of these children survived, but they and their mother continued to depend on occasional relief payments until at least 1801. Indeed, Sarah's son Robert followed his father, and his paternal grandfather and namesake, in sometimes requiring poor relief to support his family, as he struggled to make ends meet in the very difficult years at the turn of the nineteenth century.
In the development of novel materials for enhanced photovoltaic (PV) performance, it is critical to have quantitative knowledge of the initial performance, as well as the performance of these materials over the required 25-year lifetime of the PV system. Lifetime and degradation science (L&DS) allows for the development of new metrology and metrics, coupled to degradation mechanisms and rates. Induced absorbance to dose (IAD), a new metric being developed for solar radiation durability studies of solar and environmentally exposed photovoltaic materials, is defined as the rate of photodarkening or photobleaching of a material as a function of total absorbed solar radiation dose. In a reliability engineering framework, these quantitative degradation rates can be determined at various solar irradiances making possible real time and accelerated testing. The potential to predict power losses in a photovoltaic system over time caused by the accumulation of this kind of degradation can be calculated for real time applications or extrapolated for accelerated exposure conditions. Three formulations of poly (methyl methacrylate) (PMMA) used for mirror augmented PV systems were analyzed for the changes in IAD after accelerated testing.
Although antipsychotic medication is the first line of treatment for schizophrenia, many service users choose to refuse or discontinue their pharmacological treatment. Cognitive therapy (CT) has been shown to be effective when delivered in combination with antipsychotic medication, but has yet to be formally evaluated in its absence. This study evaluates CT for people with psychotic disorders who have not been taking antipsychotic medication for at least 6 months.
Twenty participants with schizophrenia spectrum disorders received CT in an open trial. Our primary outcome was psychiatric symptoms measured using the Positive and Negative Syndromes Scale (PANSS), which was administered at baseline, 9 months (end of treatment) and 15 months (follow-up). Secondary outcomes were dimensions of hallucinations and delusions, self-rated recovery and social functioning.
T tests and Wilcoxon's signed ranks tests revealed significant beneficial effects on all primary and secondary outcomes at end of treatment and follow-up, with the exception of self-rated recovery at end of treatment. Cohen's d effect sizes were moderate to large [for PANSS total, d=0.85, 95% confidence interval (CI) 0.32–1.35 at end of treatment; d=1.26, 95% CI 0.66–1.84 at follow-up]. A response rate analysis found that 35% and 50% of participants achieved at least a 50% reduction in PANSS total scores by end of therapy and follow-up respectively. No patients deteriorated significantly.
This study provides preliminary evidence that CT is an acceptable and effective treatment for people with psychosis who choose not to take antipsychotic medication. An adequately powered randomized controlled trial is warranted.
Decline in social functioning occurs in individuals who later develop psychosis.
To investigate whether baseline differences in disability are present in those who do and those who do not make a transition to psychosis in a group clinically at high risk and whether disability is a risk factor for transition.
Prospective multicentre, naturalistic field study with an 18-month follow-up period on 245 help-seeking individuals clinically at high risk. Disability was assessed with the Disability Assessment Schedule of the World Health Organization (WHODAS–II).
At baseline, the transition group displayed significantly greater difficulties in making new friends (z =−3.40, P = 0.001), maintaining a friendship (z =−3.00, P = 0.003), dealing with people they do not know (z =−2.28, P = 0.023) and joining community activities (z =−2.0, P = 0.05) compared with the non-transition group. In Cox regression, difficulties in getting along with people significantly contributed to the prediction of transition to psychosis in our sample (β = 0.569, s.e. = 0.184, Wald = 9.548, P = 0.002, hazard ratio (HR) = 1.767, 95% CI 1.238–2.550).
Certain domains of social disability might contribute to the prediction of psychosis in a sample clinically at high risk.
We present a novel process methodology for the controlled cutting of nanotubes and other nanostructures to well-controlled lengths and sizes. The continuing increase in complexity of electronic devices, coupled with decreasing size of individual elements, are placing more stringent demands on the resolution and accuracy of fabrication patterns. The ability to fabricate on a nanometer scale guarantees a continuation in miniaturization of functional devices. Particularly interesting is the application of nanotubes' chemical and electronic properties which vary with their dimensions and structure. One realization of this process includes the use of photolithography or electron beam lithography to place protective resist patterns over the nanostructures to be cut. Those sections which are not covered by the resist pattern are removed by reactive ion etching. This is a scaleable process which permits the simultaneous cutting of many nanostructures and ensembles of nanostructures. The lengths, shapes or length distributions can be predicted from theory and thus specified for a given application requirement. Nanostructures which can be cut in this process include nanotubes, nanofibers and nanoplanes. Large scale production of nanostructures with uniform length or specific size-distribution can be used in electronic applications such as field-emission transistors, optoelectronic elements, single electron devices and sensors.
Characterization of thin surficial films of oxides has become the focus of increased interest due to their applications in microelectronics. The ability to experimentally determine the electronic structure and optical properties of oxide materials permits the direct study of the interband transitions from the valence to the conduction band states. In the past years there has been much progress in the quantitative analysis of transmission electron energy loss spectroscopy (TEELS) in the electron microscope
Here we employed reflection electron energy loss function (REELS) as well as vacuum ultraviolet (VUV) spectroscopy to determine the dielectric functions of oxide materials, i.e. Al2O3, ZrO2 and SrTiO3. The two main steps in the analysis are the removal of the effects of multiple scattering from the REELS spectra followed by application of the Kramers-Kronig dispersion transforms to the single scattering energy loss function to determine the conjugate optical variable and then the complex dielectric function. The surface and bulk plasma resonance spectra for these oxide materials have been determined from VUV and REELS, along with the influence of primary electron energy on the REELS results. The relative contribution of surface and bulk plasmon oscillation in REELS has been investigated. Comparison with VUV results and existing TEELS results indicate that Kramers-Kronig analysis can also be applied to REELS spectra and the corresponding conjugate optical properties can be obtained. Quantitative studies of the electronic structure and optical properties of thin surficial films using VUV and REELS or TEELS, represent a new avenue to determine the properties of these increasingly important films.
The ‘middle sort of people’ is a social group that has been the subject of increased
historical research in the last decade. Many studies have been written, and many definitions offered of
the group, its identity, and its membership. As a result, these overlapping groups and contrasting
methods of definition have caused the nature and identity of the group to remain elusive. This study
charts the evolution of the historiography of the ‘middle sort’, and the many attempts to produce
positive and accurate definitions of the group. It suggests that the identity of the ‘middle sort’ may,
in fact, be more complex than is allowed for by existing studies, with different identities being adopted
according to social context. It concludes that while the term ‘middle sort of people’ is an appropriate
contemporary collective term for use by historians, it is much more problematic as a description of an
active, cohesive social group in the early modern period.
Clostridium perfringens isolates are currently classified into one of five biotypes on the basis of
the differential production of α-, β-, ε- and ι-toxins. Different biotypes are associated with
different diseases of man and animals. In this study a multiple PCR assay was developed to
detect the genes encoding these toxins. In addition, detection of the genes encoding the C.
perfringens enterotoxin and β2-toxin allowed subtyping of the bacteria. C. perfringens isolates
taken from a variety of animals, including foals, piglets or lambs, were genotyped using this
assay. Most of the isolates were found to be genotype A and the gene encoding β-toxin was
present in 50% of the isolates genotyped. A significant association between C. perfringens
possessing the β2-toxin gene and diarrhoea in piglets was identified, suggesting that β2-toxin
may play a key role in the pathogenesis of the disease.
The quantitative study of English land markets in the three centuries after
the close of the middle ages is still in its infancy. The medievalists,
exploiting the conveyances of customary tenants recorded in manorial
court rolls, have shown how issues such as the devolution of land within
families, the frequency with which land was sold and the behaviour of the
land market at moments of demographic or economic stress can be
addressed by the analysis of such data either aggregatively or by looking
at the landholding histories of individual participants in the land market.
Early modernists have invariably approached the study of the land market
in a non-quantitative fashion, usually as part of an attempt to make
observations about some other characteristic of English history. Stone
looked at the land market in the sixteenth and early seventeenth centuries
as part of his campaign to prove that the aristocracy was in decline,
Macfarlane to show that the property-holding behaviour of the English
was ‘individualistic’, Habbakuk to explore the strategies by which the
English aristocracy maintained its supremacy and Mingay and others to
settle the debate about the effect of enclosure on the small landowner.
The early modern land market has rarely, if ever, been seen as worthy of
discussion in its own right.
Precise and accurate knowledge of the optical properties of aluminum nitride (AlN) in the ultraviolet (UV) and visible (VIS) regions is important because of the increasing application of AlN in optical and electro-optical devices, including compact disks, phase shift lithography masks, and AlN/GaN multilayer devices. The interband optical properties in the vacuum ultraviolet (VUV) region of 6–44 eV have been investigated previously because they convey detailed information on the electronic structure and interatomic bonding of the material. In this work, we have combined spectroscopic ellipsometry with UV/VIS and VUV spectroscopy to directly determine the optical constants of AlN in this range, thereby reducing the uncertainty in the preparation of the low-energy data extrapolation essential for Kramers–Kronig analysis of VUV reflectance. We report the complex optical properties of AlN, over the range of 1.5–42 eV, showing improved agreement with theory when contrasted with earlier results.
Dangling bond defects are created during positive bias stress of amorphous silicon thin film transistors and there is an energy barrier between 0.9 and 1 eV for this process. We have studied how this energy barrier depends on the material parameters of the amorphous silicon, namely hydrogen content, hydrogen bonding, Urbach energy and intrinsic, deposition induced stress. We observe no dependence on the hydrogen content or hydrogen bonding type, but we do observe a clear dependence on the Urbach energy and the intrinsic stress. These measurements support a localized model for defect creation involving Si-Si bond breaking and the switching of a neighboring H atom to stabilize the broken bond. These results suggest that stable amorphous silicon TFTs can be obtained at low deposition temperatures by control of the deposition-induced, intrinsic stress.