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It has been suggested that a cellularly unstable laminar flame, which is freely propagating in unbounded space, can accelerate and evolve into a turbulent flame with the neighbouring flow exhibiting the basic characteristics of turbulence. Famously known as self-turbulization, this conceptual transition in the flow regime, which arises from local interactions between the propagating wrinkled flamefront and the flow, is critical in extreme events such as the deflagration-to-detonation transition (DDT) leading to supernova explosions. Recognizing that such a transition in the flow regime has not been conclusively demonstrated through experiments, in this work, we present experimental measurements of flow characteristics of flame-generated ‘turbulence’ for expanding cellular laminar flames. The energy spectra of such ‘turbulence’ at different stages of cellular instability are analysed. A subsequent scaling analysis points out that the observed energy spectra are driven by the fractal topology of the cellularly unstable flamefront.
There is compelling evidence for gradient effects of household income on school readiness. Potential mechanisms are described, yet the growth curve trajectory of maternal mental health in a child's early life has not been thoroughly investigated. We aimed to examine the relationships between household incomes, maternal mental health trajectories from antenatal to the postnatal period, and school readiness.
Prospective data from 505 mother–child dyads in a birth cohort in Singapore were used, including household income, repeated measures of maternal mental health from pregnancy to 2-years postpartum, and a range of child behavioural, socio-emotional and cognitive outcomes from 2 to 6 years of age. Antenatal mental health and its trajectory were tested as mediators in the latent growth curve models.
Household income was a robust predictor of antenatal maternal mental health and all child outcomes. Between children from the bottom and top household income quartiles, four dimensions of school readiness skills differed by a range of 0.52 (95% Cl: 0.23, 0.67) to 1.21 s.d. (95% CI: 1.02, 1.40). Thirty-eight percent of pregnant mothers in this cohort were found to have perinatal depressive and anxiety symptoms in the subclinical and clinical ranges. Poorer school readiness skills were found in children of these mothers when compared to those of mothers with little or no symptoms. After adjustment of unmeasured confounding on the indirect effect, antenatal maternal mental health provided a robust mediating path between household income and multiple school readiness outcomes (χ2 126.05, df 63, p < 0.001; RMSEA = 0.031, CFI = 0.980, SRMR = 0.034).
Pregnant mothers with mental health symptoms, particularly those from economically-challenged households, are potential targets for intervention to level the playing field of their children.
Red meat is an important dietary source of protein and many other essential nutrients including omega(n)-3 polyunsaturated fatty acids (PUFA) which provide numerous benefits to human health. It is well known that grass-fed meat contains a more favourable fatty acid profile, compared to other feeding regimes, but the feasibility of grass finishing is in decline for many farmers/producers. Therefore, alternative methods to enhance the fatty acid profile of red meats, such as beef, are needed to meet increasing consumer demands for ‘healthier’ products. This study compared plasma PUFA concentrations across cattle finished on three different feeding regimes. Three farms supplied livestock to the current study, where cattle were fed three different feeding regimes for a minimum of 15-weeks prior to slaughter. Feeding regimes were ad lib concentrate (negative control), n3-enriched ad lib concentrate (treatment) or grass-fed only (positive control). Blood was collected at slaughter into EDTA tubes and plasma aliquots were stored at -80°C until analysis. A validated gas chromatography–mass spectrometry (GC-MS) method was used to quantify individual PUFA concentrations in mg/ml [linoleic acid (LA); arachidonic acid (AA); alpha-linolenic acid (ALA); eicosapentaenoic acid (EPA); docosapentaenoic acid (DPA); docosahexaenoic acid (DHA)]. Samples from 23, 49 and 40 animals (in control, treatment & grass groups, respectively) were available for the current analysis. One-way ANOVA tests revealed significant differences between groups in all PUFA concentrations quantified (all P < 0.026). Post-hoc (LSD) tests showed mean ± SD n3 PUFA concentrations were significantly different within all three groups (all P < 0.04), increasing from negative control (0.049 ± 0.013 mg/ml), to treatment (0.095 ± 0.034 mg/ml) and grass-fed groups (0.461 ± 0.132 mg/ml). The opposite was observed for mean ± SD n6 PUFA concentrations (1.060 ± 0.297 vs. 0.918 ± 0.267 vs. 0.355 ± 0.085 mg/ml, respectively; all P < 0.02). Cattle finished on either treatment or grass regimes had a more favourable n6:n3 PUFA ratio, compared to negative control (11.98 and 0.79 vs. 22.65, respectively). This study demonstrates that the finishing diet can impact plasma PUFA concentrations of beef cattle. Animals finished on the n3-enriched concentrate had, on average, double the total n3 PUFA concentrations, as well as an improved n6:n3 ratio, compared to control cattle. These results provide preliminary data on an alternative n3-enriched feeding regime for beef cattle to improve PUFA concentrations. Further research, however, is required to confirm if such beneficial changes are also observed in bovine muscle, which would have direct benefits for consumers.
Introduction: Bronchiolitis is a viral respiratory infection and the most common reason for hospitalization of infants. Despite evidence that few interventions are beneficial in patients with bronchiolitis, other studies would have shown that a significant proportion of patients undergo various forms of low value care. This objective of this project was to 1. establish baseline management of bronchiolitis in the Calgary Zone, and 2. deliver audit and feedback (A&F) reports to pediatric emergency physicians (PEP) to identify opportunities and strategies for practice improvement. Methods: This retrospective cohort study included all patients 12 months old that presented to a Calgary emergency department or urgent care center with a diagnosis of bronchiolitis from April 1, 2013 to March 31, 2017. Using data from various electronic health data sources, we captured age, vital signs, CTAS, common therapeutic interventions (bronchodilators, steroids, antibiotics) and investigations (chest x-ray (CXR), viral studies, antibiotics). Results were stratified by site and by admission status. Descriptive statistics were used to report baseline characteristics and interventions. Interhospital ranges (IHR) were provided to compare different hospitals in the zone. For the A&F component of the project, consenting PEP received a report of both their individual and peer comparator data and an in-person multi-disciplinary facilitated feedback session. Results: We included 4023 patients from all 6 sites (range from 28 to 3316 patients). Admission rates were 21.7% (IHR 0-29%). Mean age was 5.4 months old. Bronchodilator use was 27.0% (IHR 21-41%). 22.0% of patients received a CXR (IHR 0-57%) and 30.3% had viral studies done (IHR range 0.8-33%). PEP had higher usage of viral studies (30% vs 5.7%), whereas non-PEP had higher CXR usage (46.2% vs 23.4%). 41 of 66 PEP consented to receive their individual A&F reports (62%). In the facilitated feedback session PEP 1. identified two areas (bronchodilators and viral studies) where improvements could be made and 2. discussed specific strategies to decrease practice variation and minimize low value care including development of a multi-disciplinary care pathway, alignment with in-patient management, education and repeated A&F reports. Conclusion: Significant variability exists in management of patients with bronchiolitis across different hospitals in our zone. A facilitated feedback session identified areas for improvement and multi-disciplinary strategies to reduced low value care for patients with bronchiolitis. Future phases of this project include repeated data in 6 months and implementation of a provincial care pathway for the management of bronchiolitis.
As part of further investigations into three linked haemorrhagic fever with renal syndrome (HFRS) cases in Wales and England, 21 rats from a breeding colony in Cherwell, and three rats from a household in Cheltenham were screened for hantavirus. Hantavirus RNA was detected in either the lungs and/or kidney of 17/21 (81%) of the Cherwell rats tested, higher than previously detected by blood testing alone (7/21, 33%), and in the kidneys of all three Cheltenham rats. The partial L gene sequences obtained from 10 of the Cherwell rats and the three Cheltenham rats were identical to each other and the previously reported UK Cherwell strain. Seoul hantavirus (SEOV) RNA was detected in the heart, kidney, lung, salivary gland and spleen (but not in the liver) of an individual rat from the Cherwell colony suspected of being the source of SEOV. Serum from 20/20 of the Cherwell rats and two associated HFRS cases had high levels of SEOV-specific antibodies (by virus neutralisation). The high prevalence of SEOV in both sites and the moderately severe disease in the pet rat owners suggest that SEOV in pet rats poses a greater public health risk than previously considered.
In the United States alone, ∼14,000 children are hospitalised annually with acute heart failure. The science and art of caring for these patients continues to evolve. The International Pediatric Heart Failure Summit of Johns Hopkins All Children’s Heart Institute was held on February 4 and 5, 2015. The 2015 International Pediatric Heart Failure Summit of Johns Hopkins All Children’s Heart Institute was funded through the Andrews/Daicoff Cardiovascular Program Endowment, a philanthropic collaboration between All Children’s Hospital and the Morsani College of Medicine at the University of South Florida (USF). Sponsored by All Children’s Hospital Andrews/Daicoff Cardiovascular Program, the International Pediatric Heart Failure Summit assembled leaders in clinical and scientific disciplines related to paediatric heart failure and created a multi-disciplinary “think-tank”. The purpose of this manuscript is to summarise the lessons from the 2015 International Pediatric Heart Failure Summit of Johns Hopkins All Children’s Heart Institute, to describe the “state of the art” of the treatment of paediatric cardiac failure, and to discuss future directions for research in the domain of paediatric cardiac failure.
Iron oxides resulting from the corrosion of large quantities of steel that are planned to be installed throughout a deep geological disposal facility (GDF) are expected to be one of the key surfaces of interest for controlling radionuclide behaviour under disposal conditions. Over the lengthy timescales associated with a GDF, the system is expected to become anoxic so that reduced Fe(II) phases will dominate. Batch experiments have therefore been completed in order to investigate how a model reduced Fe-oxide surface (wüstite, Fe1–xO) alters as a function of exposure to aqueous solutions with compositions representative of conditions expected within a GDF. Additional experiments were performed to constrain the effect that highly alkaline solutions (up to pH 13) have on the adsorption behaviour of the uranyl (UO22+) ion onto the surfaces of both wüstite and portlandite [Ca(OH)2; representative of the expected cementitious phases]. Surface co-ordination chemistry and speciation were determined by ex situ X-ray absorption spectroscopy measurements (both X-ray absorption near-edge structure analysis (XANES) and extended X-ray absorption fine structure analysis (EXAFS)). Diffraction, elemental analysis and XANES showed that the bulk solid composition and Fe oxidation state remained relatively unaltered over the time frame of these experiments (120 h), although under alkaline conditions possible surface hydroxylation is observed, due presumably to the formation of surface hydroxyl complexes. The surface morphology, however, is altered significantly with a large degree of roughening and an observed decrease in the average particle size. Reduction of U(VI) to U(IV) occurs during adsorption in almost all cases and this is interpreted to indicate that wüstite may be an effective reductant of U during surface adsorption. This work also shows that increasing the carbonate concentration in reactant solutions dramatically decreases the adsorption coefficients for U on both wüstite and portlandite, consistent with U speciation and surface reactivity determined in other studies. Finally, the EXAFS results include new details about exactly how U bonds to this metal oxide surface.
Cognitive–behavioural therapy (CBT) is considered to be effective for the symptoms of schizophrenia. However, this view is based mainly on meta-analysis, whose findings can be influenced by failure to consider sources of bias.
To conduct a systematic review and meta-analysis of the effectiveness of CBT for schizophrenic symptoms that includes an examination of potential sources of bias.
Data were pooled from randomised trials providing end-of-study data on overall, positive and negative symptoms. The moderating effects of randomisation, masking of outcome assessments, incompleteness of outcome data and use of a control intervention were examined. Publication bias was also investigated.
Pooled effect sizes were −0.33 (95% CI −0.47 to −0.19) in 34 studies of overall symptoms, −0.25 (95% CI −0.37 to −0.13) in 33 studies of positive symptoms and −0.13 (95% CI −0.25 to −0.01) in 34 studies of negative symptoms. Masking significantly moderated effect size in the meta-analyses of overall symptoms (effect sizes −0.62 (95% CI −0.88 to −0.35) v. −0.15 (95% CI −0.27 to −0.03), P = 0.001) and positive symptoms (effect sizes −0.57 (95% CI −0.76 to −0.39) v. −0.08 (95% CI −0.18 to 0.03), P<0.001). Use of a control intervention did not moderate effect size in any of the analyses. There was no consistent evidence of publication bias across different analyses.
Cognitive–behavioural therapy has a therapeutic effect on schizophrenic symptoms in the ‘small’ range. This reduces further when sources of bias, particularly masking, are controlled for.
The Australian Square Kilometre Array Pathfinder (ASKAP) will give us an unprecedented opportunity to investigate the transient sky at radio wavelengths. In this paper we present VAST, an ASKAP survey for Variables and Slow Transients. VAST will exploit the wide-field survey capabilities of ASKAP to enable the discovery and investigation of variable and transient phenomena from the local to the cosmological, including flare stars, intermittent pulsars, X-ray binaries, magnetars, extreme scattering events, interstellar scintillation, radio supernovae, and orphan afterglows of gamma-ray bursts. In addition, it will allow us to probe unexplored regions of parameter space where new classes of transient sources may be detected. In this paper we review the known radio transient and variable populations and the current results from blind radio surveys. We outline a comprehensive program based on a multi-tiered survey strategy to characterise the radio transient sky through detection and monitoring of transient and variable sources on the ASKAP imaging timescales of 5 s and greater. We also present an analysis of the expected source populations that we will be able to detect with VAST.
Around the world large quantities of sludge wastes derived from nuclear energy production are currently kept in storage facilities. In the UK, the British government has marked sludge removal as a top priority as these facilities are nearing the end of their operational lifetimes. Therefore chemical understanding of uranium uptake in Mg-rich sludge is critical for successful remediation strategies. Previous studies have explored uranium uptake by the calcium carbonate minerals, calcite and aragonite, under conditions applicable to both natural and anthropogenically perturbed systems. However, studies of the uptake by Mg-rich minerals such as brucite [Mg(OH)2], nesquehonite [MgCO3·3H2O] and hydromagnesite [Mg5(CO3)4 (OH)2·4H2O], have not been previously conducted. Such experiments will improve our understanding of the mobility of uranium and other actinides in natural lithologies as well as provide key information applicable to nuclear waste repository strategies involving Mg-rich phases. Experiments with mineral powders were used to determine the partition coefficients (Kd) and coordination of UO22+ during adsorption and co-precipitation with brucite, nesquehonite and hydromagnesite. The Kd values for the selected Mg-rich minerals were comparable or greater than those published for calcium carbonates. Extended X-ray absorption fine structure analysis results showed that the structure of the uranyl-triscarbonato [UO2(CO3)3] species was maintained after surface attachment and that uptake of uranyl ions took place mainly via mineral surface reactions.
A baseline survey on the prevalence of Campylobacter spp. in broiler flocks and Campylobacter spp. on broiler carcases in the UK was performed in 2008 in accordance with Commission Decision 2007/516/EC. Pooled caecal contents from each randomly selected slaughter batch, and neck and breast skin from a single carcase were examined for Campylobacter spp. The prevalence of Campylobacter in the caeca of broiler batches was 75·8% (303/400) compared to 87·3% (349/400) on broiler carcases. Overall, 27·3% of the carcases were found to be highly contaminated with Campylobacter (⩾1000 c.f.u./g). Slaughter in the summer months (June, July, August) [odds ratio (OR) 3·50], previous partial depopulation of the flock (OR 3·37), and an increased mortality at 14 days (⩾1·25% to <1·75%) (OR 2·54) were identified as significant risk factors for the most heavily Campylobacter-contaminated carcases. Four poultry companies and farm location were also found to be significantly associated with highly contaminated carcases.
We report CdTe/CdS solar cell with CdTe layer grown by sputtering method. A controlled etch and anneal process on the sputter-grown CdTe films was performed to increase the average grain size of the film. The process involved dipping the CdTe films in a saturated solution of cadmium chloride (CdCl2) in methanol (2.08 gram in 100 ml) followed by a 30 minute annealing at 400 °C. We performed various experiments on this process by varying the dipping times, drying process and annealing times and analyzed the resultant films using Scanning Electron Microscopy (SEM). We could see a clear increase in grain size from 200 nm to 5 μm after CdCl2 treatment. The process also increased the overall roughness of the sample so that more light is absorbed than reflected. We prepared solar cells using CdTe as p-type layer and CdS as n-type layer. The efficiency of the cell improved from 1.1% to 4.2% after air annealing. The effect of air-annealing is studied by means of quantum efficiency measurement.
A water vapor barrier layer is presented that is deposited entirely at temperatures below ∼100oC. Our method, using hot wire chemical vapor deposition (HWCVD), is effective in reducing the issue of pinholes in single layers of silicon nitride (SiNx) made at such low substrate temperatures. We succeeded in depositing an all hot-wire simple three-layer structure consisting of two low-temperature SiNx layers with a polymer layer in between, exhibiting a water vapor transmission rate (WVTR) as low as 5*10-6 g/m2/day, determined at a temperature of 60°C and a relative humidity of 90%. This WVTR is low enough for organic and polymer devices. In a second experiment the robustness of the barrier layer is shown with respect to environmental dust.