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Background: Ischemic stroke is a major cause of morbidity and mortality in Canada. Since 2015, mechanical thrombectomy has been the standard of care for eligible large vessel occlusions (LVOs), though anesthetic strategies remain variable. Methods: We conducted a single-center retrospective review of patients undergoing mechanical thrombectomy for anterior circulation LVOs between 2021 and 2023. Patients were categorized by anesthetic strategy (general anesthesia vs. conscious sedation), and outcomes, including time to recanalization, angiographic results (mTICI), and 90-day functional status (mRS), were compared. Statistical analyses included Student’s t-test, Mann-Whitney U-test, and Fisher’s exact test. Results: Among 226 patients, 177 (78%) received general anesthesia and 49 (22%) underwent conscious sedation. Baseline characteristics including sex, age, NIHSS, ASPECTS, collaterals, and laterality were similar between groups. Conscious sedation was associated with a statistically significant shorter time from arrival to the angiography suite to groin puncture (p=0.007), but no differences in time to recanalization (p=0.893), angiographic outcomes (p=0.987), or 90-day functional status (p=0.795) were observed. Conclusions: Conscious sedation led to faster procedural initiation, though no difference in clinical or radiographic outcome was observed. Anesthetic choice should be individualized based on patient and physician factors in acute mechanical thrombectomy.
Adolescence is a critical period for preventing substance use and mental health concerns, often targeted through separate school-based programs. However, co-occurrence is common and is related to worse outcomes. This study explores prevention effects of leading school-based prevention programs on co-occurring alcohol use and psychological distress.
Methods
Data from two Australian cluster randomized trials involving 8576 students in 97 schools were harmonized for analysis. Students received either health education (control) or one of five prevention programs (e.g. Climate Schools, PreVenture) with assessments at baseline and 6, 12, 24, and 30 or 36 months (from ages ~13–16). Multilevel multinomial regressions were used to predict the relative risk ratios (RRs) of students reporting co-occurring early alcohol use and psychological distress, alcohol use only, distress only, or neither (reference) across programs.
Results
The combined Climate Schools: Alcohol and Cannabis and Climate Schools: Mental Health courses (CSC) as well as the PreVenture program reduced the risk of adolescents reporting co-occurring alcohol use and psychological distress (36 months RRCSC = 0.37; RRPreVenture = 0.22). Other evaluated programs (excluding Climate Schools: Mental Health) only appeared effective for reducing the risk of alcohol use that occurred without distress.
Conclusions
Evidence-based programs exist that reduce the risk of early alcohol use with and without co-occurring psychological distress, though preventing psychological distress alone requires further exploration. Prevention programs appear to have different effects depending on whether alcohol use and distress present on their own or together, thus suggesting the need for tailored prevention strategies.
Microinstabilities drive turbulent fluctuations in inhomogeneous, magnetised plasmas. In the context of magnetic confinement fusion devices, this leads to an enhanced transport of particles, momentum and energy, thereby degrading confinement. In this work, we describe an application of the adjoint method to efficiently determine variations of gyrokinetic linear growth rates on a general set of external parameters in the local $\delta f$-gyrokinetic model. We then offer numerical verification of this approach. When coupled with gradient-based techniques, this methodology can facilitate the optimisation process for the microstability of the confined plasmas across a high-dimensional parameter space. We present a numerical demonstration wherein the ion-temperature-gradient instability growth rate in a tokamak plasma is minimised with respect to flux surface shaping parameters. The adjoint method approach demonstrates a significant computational speed-up compared with a finite-difference gradient calculation.
The use of mechanical restraint is a challenging area for psychiatry. Although mechanical restraint remains accepted as standard practice in some regions, there are ethical, legal and medical reasons to minimise or abolish its use. These concerns have intensified following the Convention on the Rights of Persons with Disabilities. Despite national policies to reduce use, the reporting of mechanical restraint has been poor, hampering a reasonable understanding of the epidemiology of restraint. This paper aims to develop a consistent measure of mechanical restraint and compare the measure within and across countries in the Pacific Rim.
Methods
We used the publicly available data from four Pacific Rim countries (Australia, New Zealand, Japan and the United States) to compare and contrast the reported rates of mechanical restraint. Summary measures were computed so as to enable international comparisons. Variation within each jurisdiction was also analysed.
Results
International rates of mechanical restraint in 2017 varied from 0.03 (New Zealand) to 98.8 (Japan) restraint events per million population per day, a variation greater than 3000-fold. Restraint in Australia (0.17 events per million) and the United States (0.37 events per million) fell between these two extremes. Variation as measured by restraint events per 1000 bed-days was less extreme but still substantial. Within all four countries there was also significant variation in restraint across districts. Variation across time did not show a steady reduction in restraint in any country during the period for which data were available (starting from 2003 at the earliest).
Conclusions
Policies to reduce or abolish mechanical restraint do not appear to be effecting change. It is improbable that the variation in restraint within the four examined Pacific Rim countries is accountable for by psychopathology. Greater efforts at reporting, monitoring and carrying out interventions to achieve the stated aim of reducing restraint are urgently needed.
In toroidal magnetic confinement devices, such as tokamaks and stellarators, neoclassical transport is usually an order of magnitude larger than its classical counterpart. However, when a high-collisionality species is present in a stellarator optimized for low Pfirsch–Schlüter current, its classical transport can be comparable to the neoclassical transport. In this letter, we compare neoclassical and classical fluxes and transport coefficients calculated for Wendelstein 7-X (W7-X) and Large Helical Device (LHD) cases. In W7-X, we find that the classical transport of a collisional impurity is comparable to the neoclassical transport for all radii, while it is negligible in the LHD cases, except in the vicinity of radii where the neoclassical transport changes sign. In the LHD case, electrostatic potential variations on the flux surface significantly enhance the neoclassical impurity transport, while the classical transport is largely insensitive to this effect in the cases studied.
High-$Z$ impurities in magnetic-confinement devices are prone to develop density variations on the flux surface, which can significantly affect their transport. In this paper, we generalize earlier analytic stellarator calculations of the neoclassical radial impurity flux in the mixed-collisionality regime (collisional impurities and low-collisionality bulk ions) to include the effect of such flux-surface variations. We find that only in the homogeneous density case is the transport of highly collisional impurities (in the Pfirsch–Schlüter regime) independent of the radial electric field. We study these effects for a Wendelstein 7-X (W7-X) vacuum field, with simple analytic models for the potential perturbation, under the assumption that the impurity density is given by a Boltzmann response to a perturbed potential. In the W7-X case studied, we find that larger amplitude potential perturbations cause the radial electric field to dominate the transport of the impurities. In addition, we find that classical impurity transport can be larger than the neoclassical transport in W7-X.
Epstein Barr virus (EBV) infects 95% of the global population and is associated with up to 2% of cancers globally. Immunoglobulin G (IgG) antibody levels to EBV have been shown to be heritable and associated with developing malignancies. We, therefore, performed a pilot genome-wide association analysis of anti-EBV IgG traits in an African population, using a combined approach including array genotyping, whole-genome sequencing and imputation to a panel with African sequence data. In 1562 Ugandans, we identify a variant in human leukocyte antigen (HLA)-DQA1, rs9272371 (p = 2.6 × 10−17) associated with anti-EBV nuclear antigen-1 responses. Trans-ancestry meta-analysis and fine-mapping with European-ancestry individuals suggest the presence of distinct HLA class II variants driving associations in Uganda. In addition, we identify four putative, novel, very rare African-specific loci with preliminary evidence for association with anti-viral capsid antigen IgG responses which will require replication for validation. These findings reinforce the need for the expansion of such studies in African populations with relevant datasets to capture genetic diversity.
The accumulation of impurities in the core of magnetically confined plasmas, resulting from standard collisional transport mechanisms, is a known threat to their performance as fusion energy sources. Whilst the axisymmetric tokamak systems have been shown to benefit from the effect of temperature screening, that is an outward flux of impurities driven by the temperature gradient, impurity accumulation in stellarators was thought to be inevitable, driven robustly by the inward pointing electric field characteristic of hot fusion plasmas. We have shown in Helander et al. (Phys. Rev. Lett., vol. 118, 2017a, 155002) that such screening can in principle also appear in stellarators, in the experimentally relevant mixed collisionality regime, where a highly collisional impurity species is present in a low collisionality bulk plasma. Details of the analytic calculation are presented here, along with the effect of the impurity on the bulk ion flow, which will ultimately affect the bulk contribution to the bootstrap current.
Dalapon (2,2-dichloropropionic acid), injurious to Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) and grand fir (Abies grandis (Dougl.) Lindl.) when used alone for weed control, was used with safety and even with beneficial effects when combined with atrazine [2-chloro-4-(ethylamine)-6-(isopropylamino)-s-triazine] and 2,4-D, [(2,4-dichlorophenoxy) acetic acid] at rates of up to 3.36 and 4.48 kg/ha, respectively. Harmful effects of dalapon were masked at rates up to three times those used for adequate control of grasses. This suggests a type of selectivity previously unreported. Interpretation of herbicide effects and interactions was made possible with an analytical model that separated effects of vegetation from those of herbicides on a causal basis. This technique included two-dimensional adjustment of the base of reference for a four-dimensional response-surface equation. This surface fit observed data as well as a single multiple-regression equation, which included all variables. This approach, however, estimated herbicide parameters with appropriate consideration of environmental data and permitted interpretation with respect to cause.
Introduction: Data regarding adverse events (AEs) (unintended harm to the patient from health care provided) among children seen in the emergency department (ED) are scarce despite the high risk setting and population. The objective of our study was to estimate the risk and type of AEs, and their preventability and severity, among children treated in pediatric EDs. Methods: Our prospective cohort study enrolled children <18 years of age presenting for care during 21 randomized 8 hr-shifts at 9 pediatric EDs from Nov 2014 to October 2015. Exclusion criteria included unavailability for follow-up or insurmountable language barrier. RAs collected demographic, medical history, ED course, and systems level data. At day 7, 14, and 21 a RA administered a structured telephone interview to all patients to identify flagged outcomes (e.g. repeat ED visits, worsening/new symptoms, etc). A validated trigger tool was used to screen admitted patients’ health records. For any patients with a flagged outcome or trigger, 3 ED physicians independently determined if an AE occurred. Primary outcome was the proportion of patients with an AE related to ED care within 3 weeks of their ED visit. Results: We enrolled 6377 (72.0%) of 8855 eligible patients; 545 (8.5%) were lost to follow-up. Median age was 4.4 years (range 3 months to 17.9 yrs). Eight hundred and seventy seven (13.8%) were triaged as CTAS 1 or 2, 2638 (41.4%) as CTAS 3, and 2839 (44.7%) as CTAS 4 or 5. Top entrance complaints were fever (11.2%) and cough (8.8%). Flagged outcomes/triggers were identified for 2047 (32.1%) patients. While 252 (4.0%) patients suffered at least one AE within 3 weeks of ED visit, 163 (2.6%) suffered an AE related to ED care. In total, patients suffered 286 AEs, most (67.9%) being preventable. The most common AE types were management issues (32.5%) and procedural complications (21.9%). The need for a medical intervention (33.9%) and another ED visit (33.9%) were the most frequent clinical consequences. In univariate analysis, older age, chronic conditions, hospital admission, initial location in high acuity area of the ED, having >1 ED MD or a consultant involved in care, (all p<0.001) and longer length of stay (p<0.01) were associated with AEs. Conclusion: While our multicentre study found a lower risk of AEs among pediatric ED patients than reported among pediatric inpatients and adult ED patients, a high proportion of these AEs were preventable.
In North America, terrestrial records of biodiversity and climate change that span Marine Oxygen Isotope Stage (MIS) 5 are rare. Where found, they provide insight into how the coupling of the ocean–atmosphere system is manifested in biotic and environmental records and how the biosphere responds to climate change. In 2010–2011, construction at Ziegler Reservoir near Snowmass Village, Colorado (USA) revealed a nearly continuous, lacustrine/wetland sedimentary sequence that preserved evidence of past plant communities between ~140 and 55 ka, including all of MIS 5. At an elevation of 2705 m, the Ziegler Reservoir fossil site also contained thousands of well-preserved bones of late Pleistocene megafauna, including mastodons, mammoths, ground sloths, horses, camels, deer, bison, black bear, coyotes, and bighorn sheep. In addition, the site contained more than 26,000 bones from at least 30 species of small animals including salamanders, otters, muskrats, minks, rabbits, beavers, frogs, lizards, snakes, fish, and birds. The combination of macro- and micro-vertebrates, invertebrates, terrestrial and aquatic plant macrofossils, a detailed pollen record, and a robust, directly dated stratigraphic framework shows that high-elevation ecosystems in the Rocky Mountains of Colorado are climatically sensitive and varied dramatically throughout MIS 5.
With the changing distribution of infectious diseases, and an increase in the burden of non-communicable diseases, low- and middle-income countries, including those in Africa, will need to expand their health care capacities to effectively respond to these epidemiological transitions. The interrelated risk factors for chronic infectious and non-communicable diseases and the need for long-term disease management, argue for combined strategies to understand their underlying causes and to design strategies for effective prevention and long-term care. Through multidisciplinary research and implementation partnerships, we advocate an integrated approach for research and healthcare for chronic diseases in Africa.
Toxigenic strains of Vibrio cholerae serogroups O1 and O139 have caused cholera epidemics, but other serogroups – such as O75 or O141 – can also produce cholera toxin and cause severe watery diarrhoea similar to cholera. We describe 31 years of surveillance for toxigenic non-O1, non-O139 infections in the United States and map these infections to the state where the exposure probably originated. While serogroups O75 and O141 are closely related pathogens, they differ in how and where they infect people. Oysters were the main vehicle for O75 infection. The vehicles for O141 infection include oysters, clams, and freshwater in lakes and rivers. The patients infected with serogroup O75 who had food traceback information available ate raw oysters from Florida. Patients infected with O141 ate oysters from Florida and clams from New Jersey, and those who only reported being exposed to freshwater were exposed in Arizona, Michigan, Missouri, and Texas. Improving the safety of oysters, specifically, should help prevent future illnesses from these toxigenic strains and similar pathogenic Vibrio species. Post-harvest processing of raw oysters, such as individual quick freezing, heat-cool pasteurization, and high hydrostatic pressurization, should be considered.
The yields of spring barley during a medium-term (7 years) compost and slurry addition experiment and the soil carbon (C) and nitrogen (N) contents, bacterial community structure, soil microbial biomass and soil respiration rates have been determined to assess the effects of repeated, and in some cases very large, organic amendments on soil and crop parameters. For compost, total additions were equivalent to up to 119 t C/ha and 1·7 t N/ha and for slurry they were 25 t C/ha and 0·35 t N/ha over 7 years, which represented very large additions compared to control soil C and N contents (69 t C/ha and 0·3 t N/ha in the 0–30 cm soil depth). There was an initial positive response to compost and slurry addition on barley yield, but over the experiment the yield differential between the amounts of compost addition declined, indicating that repeated addition of compost at a lower rate over several years had the same cumulative effect as a large single compost application. By the end of the experiment it was clear that the addition of compost and slurry increased soil C and N contents, especially towards the top of the soil profile, as well as soil respiration rates. However, the increases in soil C and N contents were not proportional to the amount of C and N added, suggesting either that: (i) a portion of the added C and N was more vulnerable to loss; (ii) that its addition rendered another C or N pool in the soil more susceptible to loss; or (iii) that the C inputs from additional crop productivity did not increase in line with the organic amendments. Soil microbial biomass was depressed at the highest rate of organic amendment, and whilst this may have been due to genuine toxic or inhibitory effects of large amounts of compost, it could also be due to the inaccuracy of the substrate-induced respiration approach used for determining soil biomass when there is a large supply of organic matter. At the highest compost addition, the bacterial community structure was significantly altered, suggesting that the amendments significantly altered soil community dynamics.
This paper describes the current status of knowledge regarding the impact of aviation on the atmosphere. The growth of the aviation industry is likely to continue in the future and at present there are significant concerns that this will adversely affect climate and local air quality in the vicinity of airports. Indeed, it is possible that air quality may become a constraint to increased capacity of some large hub airports. Currently the radiative forcing impact from aircraft emissions, other than CO2, are not accounted for in the International Civil Aviation Organization emission trading scheme proposals. Taking only this approach, emissions trading could, in theory, increase the radiative forcing, rather than decrease it. The study of improved ‘environmentally friendly’ flight is still in its infancy, however any proposed and actual new developments, in terms of technology and operational practice, should include an environmental assessment.
Epidemiological data regarding group A streptococcal (GAS) infections in South East Asia are scarce with no information from Laos. We characterized emm types, emm clusters and the antibiotic resistance profile of 124 GAS isolates recovered in Laos during 2004–2013. Most strains were recovered from skin and invasive infections (76% and 19%, respectively). Thirty-four emm types were identified as belonging to 12 emm clusters and no novel emm types were identified. No significant differences were observed in the distribution of emm types or emm clusters according to age or site of recovery (skin or invasive infections). There was moderate strain diversity in this country but considerable differences in emm-type distribution between Laos, Thailand and Cambodia. Vaccine coverage was high for the J8 vaccine candidate. The theoretical coverage for the 30-valent vaccine candidate needs further investigation. Antibiotic resistance was moderate to erythromycin and chloramphenicol (8% and 7%, respectively) and low to ofloxacin (<1%).
We have mapped cold atomic gas in 21cm line H i self-absorption (HISA) at arcminute resolution over more than 90% of the Milky Way's disk. To probe the formation of H2 clouds, we have compared our HISA distribution with CO J = 1-0 line emission. Few HISA features in the outer Galaxy have CO at the same position and velocity, while most inner-Galaxy HISA has overlapping CO. But many apparent inner-Galaxy HISA-CO associations can be explained as chance superpositions, so most inner-Galaxy HISA may also be CO-free. Since standard equilibrium cloud models cannot explain the very cold H i in many HISA features without molecules being present, these clouds may instead have significant CO-dark H2.
US cholera surveillance offers insight into global and domestic trends. Between 2001 and 2011, 111 cases were reported to the Centers for Disease Control and Prevention. Cholera was associated with international travel in 90 (81%) patients and was domestically acquired in 20 (18%) patients; for one patient, information was not available. From January 2001 to October 2010, the 42 (47%) travel-associated cases were associated with travel to Asia. In October 2010, a cholera epidemic started in Haiti, soon spreading to the Dominican Republic (Hispaniola). From then to December 2011, 40 (83%) of the 48 travel-associated cases were associated with travel to Hispaniola. Of 20 patients who acquired cholera domestically, 17 (85%) reported seafood consumption; 10 (59%) ate seafood from the US Gulf Coast. In summary, an increase in travel-associated US cholera cases was associated with epidemic cholera in Hispaniola in 2010–2011. Travel to Asia and consumption of Gulf Coast seafood remained important sources of US cholera cases.