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Introduction: We previously derived (N = 559) and validated (N = 1,100) the 10-item Ottawa Heart Failure Risk Scale (OHFRS), to assist with disposition decisions for patients with acute heart failure (AHF) in the emergency department (ED). In the current study we sought to use a larger dataset to develop a more concise and more accurate risk scale. Methods: We analyzed data from the prior two studies and from a new cohort. For all 3 groups we conducted prospective cohort studies that enrolled patients who required treatment for AHF at 8 tertiary care hospital EDs. Patients were followed for 30 days. The primary outcome was short-term serious outcome (SSO), defined as death within 30 days, intubation or non-invasive ventilation (NIV) after admission, myocardial infarction, or relapse resulting in hospital admission within 14 days. The fully pre-specified logistic regression model with 13 predictors (where age, pCO2, and SaO2 were modeled using spline functions) was fitted to 10 multiple imputation datasets. Harrell's fast stepdown procedure reduced the number of variables. We calculated the potential impact on sensitivity (95% CI) for SSO and hospital admissions, and estimated a sample size of 2,000 patients. Results: The 1,986 patients had mean age 77.3 years, male 54.1%, EMS arrival 41.2%, IV NTG 3.3%, ED NIV 5.4%, admission on initial visit 49.5%. Overall there were 236 (11.9%) SSOs including 61 deaths (3.1%), meaning that current admission practice sensitivity for SSO was only 59.7%. The final HEARTRISK6 scale is comprised of 6 variables (points) (C-statistic 0.68): Valvular heart disease (2) Antiarrhythmic medication (2) ED non-invasive ventilation (3) Creatinine 80–150 (1); ≥150 (3) Troponin ≥3x URL (2) Walk test failed (1). The probability of SSO ranged from 4.8% for a total score of 0 to 62.4% for a score of 10, showing good calibration. Choosing a HEARTRISK6 total point admission threshold of ≥3 would yield sensitivity of 70.8% (95%CI 64.5-76.5) for SSO with a slight decrease in admissions to 47.9%. Choosing a threshold of ≥2 would yield a sensitivity of 84.3% (95%CI 79.0-88.7) but require 66.6% admissions. Conclusion: Using a large prospectively collected dataset, we created a more concise and more sensitive risk scale to assist with admission decisions for patients with AHF in the ED. Implementation of the HEARTRISK6 scale should lead to safer and more efficient disposition decisions, with more high-risk patients being admitted and more low-risk patients being discharged.
Introduction: Endotracheal intubation (ETI) is a lifesaving procedure commonly performed by emergency department (ED) physicians that may lead to patient discomfort or adverse events (e.g., unintended extubation) if sedation is inadequate. No ED-based sedation guidelines currently exist, so individual practice varies widely. This study's objective was to describe the self-reported post-ETI sedation practice of Canadian adult ED physicians. Methods: An anonymous, cross-sectional, web-based survey featuring 7 common ED scenarios requiring ETI was distributed to adult ED physician members of the Canadian Association of Emergency Physicians (CAEP). Scenarios included post-cardiac arrest, hypercapnic and hypoxic respiratory failure, status epilepticus, polytrauma, traumatic brain injury, and toxicology. Participants indicated first and second choice of sedative medication following ETI, as well as bolus vs. infusion administration in each scenario. Data was presented by descriptive statistics. Results: 207 (response rate 16.8%) ED physicians responded to the survey. Emergency medicine training of respondents included CCFP-EM (47.0%), FRCPC (35.8%), and CCFP (13.9%). 51.0% of respondents work primarily in academic/teaching hospitals and 40.4% work in community teaching hospitals. On average, responding physicians report providing care for 4.9 ± 6.8 (mean ± SD) intubated adult patients per month for varying durations (39.2% for 1–2 hours, 27.8% for 2–4 hours, and 22.7% for ≤1 hour). Combining all clinical scenarios, propofol was the most frequently used medication for post-ETI sedation (38.0% of all responses) and was the most frequently used agent except for the post-cardiac arrest, polytrauma, and hypercapnic respiratory failure scenarios. Ketamine was used second most frequently (28.2%), with midazolam being third most common (14.5%). Post-ETI sedation was provided by > 98% of physicians in all situations except the post-cardiac arrest (26.1% indicating no sedation) and toxicology (15.5% indicating no sedation) scenarios. Sedation was provided by infusion in 74.6% of cases and bolus in 25.4%. Conclusion: Significant practice variability with respect to post-ETI sedation exists amongst Canadian emergency physicians. Future quality improvement studies should examine sedation provided in real clinical scenarios with a goal of establishing best sedation practices to improve patient safety and quality of care.
Introduction: Acute aortic syndrome (AAS) is a time sensitive aortic catastrophe that is often misdiagnosed. There are currently no Canadian guidelines to aid in diagnosis. Our goal was to adapt the existing American Heart Association (AHA) and European Society of Cardiology (ESC) diagnostic algorithms for AAS into a Canadian evidence based best practices algorithm targeted for emergency medicine physicians. Methods: We chose to adapt existing high-quality clinical practice guidelines (CPG) previously developed by the AHA/ESC using the GRADE ADOLOPMENT approach. We created a National Advisory Committee consisting of 21 members from across Canada including academic, community and remote/rural emergency physicians/nurses, cardiothoracic and cardiovascular surgeons, cardiac anesthesiologists, critical care physicians, cardiologist, radiologists and patient representatives. The Advisory Committee communicated through multiple teleconference meetings, emails and a one-day in person meeting. The panel prioritized questions and outcomes, using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess evidence and make recommendations. The algorithm was prepared and revised through feedback and discussions and through an iterative process until consensus was achieved. Results: The diagnostic algorithm is comprised of an updated pre test probability assessment tool with further testing recommendations based on risk level. The updated tool incorporates likelihood of an alternative diagnosis and point of care ultrasound. The final best practice diagnostic algorithm defined risk levels as Low (0.5% no further testing), Moderate (0.6-5% further testing required) and High ( >5% computed tomography, magnetic resonance imaging, trans esophageal echocardiography). During the consensus and feedback processes, we addressed a number of issues and concerns. D-dimer can be used to reduce probability of AAS in an intermediate risk group, but should not be used in a low or high-risk group. Ultrasound was incorporated as a bedside clinical examination option in pre test probability assessment for aortic insufficiency, abdominal/thoracic aortic aneurysms. Conclusion: We have created the first Canadian best practice diagnostic algorithm for AAS. We hope this diagnostic algorithm will standardize and improve diagnosis of AAS in all emergency departments across Canada.
After five positive randomized controlled trials showed benefit of mechanical thrombectomy in the management of acute ischemic stroke with emergent large-vessel occlusion, a multi-society meeting was organized during the 17th Congress of the World Federation of Interventional and Therapeutic Neuroradiology in October 2017 in Budapest, Hungary. This multi-society meeting was dedicated to establish standards of practice in acute ischemic stroke intervention aiming for a consensus on the minimum requirements for centers providing such treatment. In an ideal situation, all patients would be treated at a center offering a full spectrum of neuroendovascular care (a level 1 center). However, for geographical reasons, some patients are unable to reach such a center in a reasonable period of time. With this in mind, the group paid special attention to define recommendations on the prerequisites of organizing stroke centers providing medical thrombectomy for acute ischemic stroke, but not for other neurovascular diseases (level 2 centers). Finally, some centers will have a stroke unit and offer intravenous thrombolysis, but not any endovascular stroke therapy (level 3 centers). Together, these level 1, 2, and 3 centers form a complete stroke system of care. The multi-society group provides recommendations and a framework for the development of medical thrombectomy services worldwide.
Normal odd-chain SFA (OCSFA), particularly tridecanoic acid (n-13 : 0), pentadecanoic acid (n-15 : 0) and heptadecanoic acid (n-17 : 0), are normal components of dairy products, beef and seafood. The ratio of n-15 : 0:n-17 : 0 in ruminant foods (dairy products and beef) is 2:1, while in seafood and human tissues it is 1:2, and their appearance in plasma is often used as a marker for ruminant fat intake. Human elongases encoded by elongation of very long-chain fatty acid (ELOVL)1, ELOVL3, ELOVL6 and ELOVL7 catalyse biosynthesis of the dominant even-chain SFA; however, there are no reports of elongase function on OCSFA. ELOVL transfected MCF7 cells were treated with n-13 : 0, n-15 : 0 or n-17 : 0 (80 µm) and products analysed. ELOVL6 catalysed elongation of n-13 : 0→n-15 : 0 and n-15 : 0→n-17 : 0; and ELOVL7 had modest activity toward n-15 : 0 (n-15 : 0→n-17 : 0). No elongation activity was detected for n-17 : 0→n-19 : 0. Our data expand ELOVL specificity to OCSFA, providing the first molecular evidence demonstrating ELOVL6 as the major elongase acting on OCSFA n-13 : 0 and n-15 : 0 fatty acids. Studies of food intake relying on OCSFA as a biomarker should consider endogenous human metabolism when relying on OCSFA ratios to indicate specific food intake.
Monolithic integrated thin film tandem solar cells consisting of a high bandgap perovskite top cell and a low bandgap thin film bottom cell are expected to reach higher power conversion efficiencies (PCEs) with lower manufacturing cost and environmental impacts than the market-dominant crystalline silicon photovoltaics. There have been several demonstrations of 4-terminal and 2-terminal perovskite tandem devices with CuInGaSe2 (CIGS) or CuInSe2 (CIS) and, similar to the other tandem structures, the optimization of this device relies on optimal choice for the perovskite bandgap and thickness. Therefore, further advancement will be enabled by tuning the perovskite absorber to maximize the photocurrent limited by the current match condition. Here, we systematically study the optical absorption and transmission of perovskite thin films with varying absorber band gap. Based on these results, we model the photocurrent generations in both perovskite and CIS subcells and estimate the performances of projected tandem devices by considering the ideally functioning perovskite and CIS device. Our results show that for perovskite layers with 500 nm thickness the optimal bandgap is around 1.6 eV. With these configurations, PCEs above 20% could be achieved by monolithically integrated perovskite/CIS tandem solar cells. Also by modelling the absorption at every layer we calculate the quantum efficiency at each subcell in addition to tracking optical losses.
Methods of obtaining large grain size and high crystallinity in absorber materials play an important role in fabrication of high-performance methylammonium lead iodide (MAPbI3) perovskite solar cells. Here we study the effect of adding small concentrations of Cd2+, Zn2+, and Fe2+salts to the perovskite precursor solution used in the single-step solution fabrication process. Enhanced grain size and crystallinity in MAPbI3 films were obtained by using 0.1% of Cd2+ or Zn2+in the precursor solution. Consequently, solar cells constructed with Cd- and Zn-doped perovskite films show a significant improvement in device performance. These results suggest that the process may be an effective and facile method to fabricate high-efficiency perovskite photovoltaic devices.
Two new species of egg parasitoids, Oobius saimaensis Yao and Mottern new species and Oobius fleischeri Yao and Duan new species (Hymenoptera: Encyrtidae), are described from eggs of Agrilus fleischeri Obenberger, 1925 (Coleoptera: Buprestidae). Agrilus fleischeri is a phloem-feeding woodborer of poplar (Populus Linnaeus; Salicaceae) in northeastern China. These two species can be distinguished morphologically as O. fleischeri has five tarsomeres and O. saimaensis has four tarsomeres. Although O. saimaensis is morphologically similar to its sympatric congener O. agrili Zhang and Hang, 2005, an important natural enemy of the invasive emerald ash borer, Agrilus planipennis Fairmaire, 1888, molecular phylogenetics and morphological data indicate that they are distinct species. Phylogenetic relationships among the new species and other closely related species are also inferred by using DNA sequence data from several ribosomal and mitochondrial genes. In addition, we expand the known distribution of Oobius primorskyensis Yao and Duan, 2016 to include South Korea.
Curcumin has been attributed with antioxidant, anti-inflammatory, antibacterial activities, and has shown highly protective effects against enteropathogenic bacteria and mycotoxins. Ochratoxin A (OTA) is one of the major intestinal pathogenic mycotoxins. The possible effect of curcumin on the alleviation of enterotoxicity induced by OTA is unknown. The effects of dietary curcumin supplementation on OTA-induced oxidative stress, intestinal barrier and mitochondrial dysfunctions were examined in young ducks. A total of 540 mixed-sex 1-day-old White Pekin ducklings with initial BW (43.4±0.1 g) were randomly assigned into controls (fed only the basal diet), a group fed an OTA-contaminated diet (2 mg/kg feed), and a group fed the same OTA-contaminated feed plus 400 mg/kg of curcumin. Each treatment consisted of six replicates, each containing 30 ducklings and treatment lasted for 21 days. There was a significant decrease in average daily gain (ADG) and increased feed : gain caused by OTA (P<0.05); curcumin co-treatment prevented the decrease in BW and ADG compared with the OTA group (P<0.05). Histopathological and ultrastructural examination showed clear signs of enterotoxicity caused by OTA, but these changes were largely prevented by curcumin supplementation. Curcumin decreased the concentrations of interleukin-1β, tumor necrosis factor-α and malondialdehyde, and increased the activity of glutathione peroxidase induced by OTA in the jejunal mucosa of ducks (P<0.05). Additionally, curcumin increased jejunal mucosa occludin and tight junction protein 1 mRNA and protein levels, and decreased those of ρ-associated protein kinase 1 (P<0.05). Notably, curcumin inhibited the increased expression of apoptosis-related genes, and downregulated mitochondrial transcription factors A, B1 and B2 caused by OTA without any effects on RNA polymerase mitochondrial (P<0.05). These results indicated that curcumin could protect ducks from OTA-induced impairment of intestinal barrier function and mitochondrial integrity.
The triplite LiFeSO4F displays both the highest potential ever reported for an Fe-based compound, as well as a comparable specific energy with that of popular LiFePO4. The synthesis is still a challenge because the present approaches are connected with long time, special equipments or organic reagents, etc. In this work, the triplite LiFeSO4F powder was synthesized through an ambient two-step solid-state route. The reaction process and phase purity were analyzed, coupled with structure refinement and electrochemical test.
Surface exfoliation was observed on single-crystal silicon surface under the action of compressed plasma flow (CPF). This phenomenon is mainly attributed to the strong transient thermal stress impact induced by CPF. To gain a better understanding of the mechanism, a micro scale model combined with thermal conduction and linear elastic fracture mechanics was built to analyze the thermal stress distribution after energy deposition. After computation with finite element method, J integral parameter was applied as the criterion for fracture initiation evaluation. It was demonstrated that the formation of surface exfoliation calls for specific material, crack depth, and CPF parameter. The results are potentially valuable for plasma/matter interaction understanding and CPF parameter optimization.
Leafy spurge (Euphorbia esula L.) is an invasive perennial weed infesting range and recreational lands of North America. Previous research and omics projects with E. esula have helped develop it as a model for studying many aspects of perennial plant development and response to abiotic stress. However, the lack of an assembled genome for E. esula has limited the power of previous transcriptomics studies to identify functional promoter elements and transcription factor binding sites. An assembled genome for E. esula would enhance our understanding of signaling processes controlling plant development and responses to environmental stress and provide a better understanding of genetic factors impacting weediness traits, evolution, and herbicide resistance. A comprehensive transcriptome database would also assist in analyzing future RNA-seq studies and is needed to annotate and assess genomic sequence assemblies. Here, we assembled and annotated 56,234 unigenes from an assembly of 589,235 RNA-seq-derived contigs and a previously published Sanger-sequenced expressed sequence tag collection. The resulting data indicate that we now have sequence for >90% of the expressed E. esula protein-coding genes. We also assembled the gene space of E. esula by using a limited coverage (18X) genomic sequence database. In this study, the programs Velvet and Trinity produced the best gene-space assemblies based on representation of expressed and conserved eukaryotic genes. The results indicate that E. esula contains as much as 23% repetitive sequences, of which 11% are unique. Our sequence data were also sufficient for assembling a full chloroplast and partial mitochondrial genome. Further, marker analysis identified more than 150,000 high-quality variants in our E. esula L-RNA–scaffolded, whole-genome, Trinity-assembled genome. Based on these results, E. esula appears to have limited heterozygosity. This study provides a blueprint for low-cost genomic assemblies in weed species and new resources for identifying conserved and novel promoter regions among coordinately expressed genes of E. esula.
The Chinese Solar and Geophysical Data (CSGD) was first issued at the Beijing Astronomical Observatory, Chinese Academy of Sciences (now the headquarter of the National Astronomical Observatories, Chinese Academy of Sciences) in 1971, when China’s satellite-industry was booming. CSGD covers the observational data (observations of the sunspots, solar flares, solar radio bursts, ionospheric storm and geomagnetic storm) from a couple of domestic observatories and the forecast data. The compiler of CSGD still keeps the data exchange with other institutes worldwide. The type of the dataset includes texts, tables, figures and so on. Up to now, we have electronized all the historic archives, making them easily accessible to people who are interested in them.
In the light curves of some solar-type stars, both rotational modulation (caused by corotating bright or dark magnetic features) and flare phenomena can be seen simultaneously. Based on these light curve observations, the relation between stellar magnetic feature activity (reflected by the rotational modulation component of the light curves) and flare activity can be investigated. Here, we analyze the light curve data of a flare-abundant solar-type star, KIC 6034120, observed with Kepler space telescope, and describe magnetic feature activity property by fluctuation range of light curves and flare activity property by time occupation ratio of flares. Distinct phase difference between long-term magnetic feature activity and flare activity is found for this star, which indicates that the source regions of stellar flares (e.g., starspots) on this star do not dominate the rotational modulation of light curves, yet they might be related to a same stellar dynamo process.
Although childhood adversity is a strong determinant of psychopathology, it remains unclear whether there are ‘sensitive periods’ when a first episode of adversity is most harmful.
To examine whether variation in the developmental timing of a first episode of interpersonal violence (up to age 18) associates with risk for psychopathology.
Using cross-sectional data, we examined the association between age at first exposure to four types of interpersonal violence (physical abuse by parents, physical abuse by others, rape, and sexual assault/molestation) and onset of four classes of DSM-IV disorders (distress, fear, behaviour, substance use) (n=9984). Age at exposure was defined as: early childhood (ages 0–5), middle childhood (ages 6–10) and adolescence (ages 11–18).
Exposure to interpersonal violence at any age period about doubled the risk of a psychiatric disorder (odds ratios (ORs) = 1.51–2.52). However, few differences in risk were observed based on the timing of first exposure. After conducting 20 tests of association, only three significant differences in risk were observed based on the timing of exposure; these results suggested an elevated risk of behaviour disorder among youth first exposed to any type of interpersonal violence during adolescence (OR = 2.37, 95% CI 1.69–3.34), especially being beaten by another person (OR = 2.44; 95% CI 1.57–3.79), and an elevated risk of substance use disorder among youth beaten by someone during adolescence (OR=2.77, 95% CI 1.94–3.96).
Children exposed to interpersonal violence had an elevated risk of psychiatric disorder. However, age at first episode of exposure was largely unassociated with psychopathology risk.
Breeding programmes for the Holstein-Friesian have historically focused on improved milk production with little emphasis on functional traits such as fertility or disease resistance (Yan et al., 2006). Recently, a major breeding programme has been adopted in Northern Ireland using the cross-breeding technique (Holstein cows x Jersey sires) with the aim of improving fertility and disease resistance of dairy cows whilst maintaining milk production capacity. The objectives of the present study were to evaluate possible breed differences in the efficiency of energy utilisation between Holstein and Jersey-Holstein dairy cows offered mixed diets of grass silage with a low or high level of concentrates.
Organic acids, most commonly fumarate and malate, when offered to ruminants have been shown to produce a decrease in methane emissions along with an increase in in vitro DM digestibility in rumen fluid taken from sheep (López et al., 1999). They are classed as ‘preservatives’ in the list of feed additives authorised by EU legislation, and as such are permitted for use in livestock (Castillo et al., 2004). However, the addition of fumaric acid to the diet has been associated with inappetance and problems of reduced rumen pH. Fumaric acid encapsulated in a soya oil capsule enables a slow release of fumaric acid in the rumen, which should overcome these problems. Encapsulated fumaric acid (EFA), when offered to lambs as 10% of the diet, reduced methane emissions by 75% and increased feed conversion efficiency by 20% (Wallace et al., 2006). To date, no in vivo studies have been carried out on dairy cattle. Therefore, the objective of this study was to determine the effect of addition of EFA on animal performance and methane production from grazing dairy cows.