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We apply two methods to estimate the 21-cm bispectrum from data taken within the Epoch of Reionisation (EoR) project of the Murchison Widefield Array (MWA). Using data acquired with the Phase II compact array allows a direct bispectrum estimate to be undertaken on the multiple redundantly spaced triangles of antenna tiles, as well as an estimate based on data gridded to the uv-plane. The direct and gridded bispectrum estimators are applied to 21 h of high-band (167–197 MHz; z = 6.2–7.5) data from the 2016 and 2017 observing seasons. Analytic predictions for the bispectrum bias and variance for point-source foregrounds are derived. We compare the output of these approaches, the foreground contribution to the signal, and future prospects for measuring the bispectra with redundant and non-redundant arrays. We find that some triangle configurations yield bispectrum estimates that are consistent with the expected noise level after 10 h, while equilateral configurations are strongly foreground-dominated. Careful choice of triangle configurations may be made to reduce foreground bias that hinders power spectrum estimators, and the 21-cm bispectrum may be accessible in less time than the 21-cm power spectrum for some wave modes, with detections in hundreds of hours.
A national need is to prepare for and respond to accidental or intentional disasters categorized as chemical, biological, radiological, nuclear, or explosive (CBRNE). These incidents require specific subject-matter expertise, yet have commonalities. We identify 7 core elements comprising CBRNE science that require integration for effective preparedness planning and public health and medical response and recovery. These core elements are (1) basic and clinical sciences, (2) modeling and systems management, (3) planning, (4) response and incident management, (5) recovery and resilience, (6) lessons learned, and (7) continuous improvement. A key feature is the ability of relevant subject matter experts to integrate information into response operations. We propose the CBRNE medical operations science support expert as a professional who (1) understands that CBRNE incidents require an integrated systems approach, (2) understands the key functions and contributions of CBRNE science practitioners, (3) helps direct strategic and tactical CBRNE planning and responses through first-hand experience, and (4) provides advice to senior decision-makers managing response activities. Recognition of both CBRNE science as a distinct competency and the establishment of the CBRNE medical operations science support expert informs the public of the enormous progress made, broadcasts opportunities for new talent, and enhances the sophistication and analytic expertise of senior managers planning for and responding to CBRNE incidents.
Shiga toxin-producing Escherichia coli (STEC) infection can cause serious illness including haemolytic uraemic syndrome. The role of socio-economic status (SES) in differential clinical presentation and exposure to potential risk factors amongst STEC cases has not previously been reported in England. We conducted an observational study using a dataset of all STEC cases identified in England, 2010–2015. Odds ratios for clinical characteristics of cases and foodborne, waterborne and environmental risk factors were estimated using logistic regression, stratified by SES, adjusting for baseline demographic factors. Incidence was higher in the highest SES group compared to the lowest (RR 1.54, 95% CI 1.19–2.00). Odds of Accident and Emergency attendance (OR 1.35, 95% CI 1.10–1.75) and hospitalisation (OR 1.71, 95% CI 1.36–2.15) because of illness were higher in the most disadvantaged compared to the least, suggesting potential lower ascertainment of milder cases or delayed care-seeking behaviour in disadvantaged groups. Advantaged individuals were significantly more likely to report salad/fruit/vegetable/herb consumption (OR 1.59, 95% CI 1.16–2.17), non-UK or UK travel (OR 1.76, 95% CI 1.40–2.27; OR 1.85, 95% CI 1.35–2.56) and environmental exposures (walking in a paddock, OR 1.82, 95% CI 1.22–2.70; soil contact, OR 1.52, 95% CI 2.13–1.09) suggesting other unmeasured risks, such as person-to-person transmission, could be more important in the most disadvantaged group.
Shiga-toxin producing Escherichia coli (STEC) is a pathogen that can cause bloody diarrhoea and severe complications. Cases occur sporadically but outbreaks are also common. Understanding the incubation period distribution and factors influencing it will help in the investigation of exposures and consequent disease control. We extracted individual patient data for STEC cases associated with outbreaks with a known source of exposure in England and Wales. The incubation period was derived and cases were described according to patient and outbreak characteristics. We tested for heterogeneity in reported incubation period between outbreaks and described the pattern of heterogeneity. We employed a multi-level regression model to examine the relationship between patient characteristics such as age, gender and reported symptoms; and outbreak characteristics such as mode of transmission with the incubation period. A total of 205 cases from 41 outbreaks were included in the study, of which 64 cases (31%) were from a single outbreak. The median incubation period was 4 days. Cases reporting bloody diarrhoea reported shorter incubation periods compared with cases without bloody diarrhoea, and likewise, cases aged between 40 and 59 years reported shorter incubation period compared with other age groups. It is recommended that public health officials consider the characteristics of cases involved in an outbreak in order to inform the outbreak investigation and the period of exposure to be investigated.
Tissue engineering aims to grow artificial tissues in vitro to replace those in the body that have been damaged through age, trauma or disease. A recent approach to engineer artificial cartilage involves seeding cells within a scaffold consisting of an interconnected 3D-printed lattice of polymer fibres combined with a cast or printed hydrogel, and subjecting the construct (cell-seeded scaffold) to an applied load in a bioreactor. A key question is to understand how the applied load is distributed throughout the construct. To address this, we employ homogenisation theory to derive equations governing the effective macroscale material properties of a periodic, elastic–poroelastic composite. We treat the fibres as a linear elastic material and the hydrogel as a poroelastic material, and exploit the disparate length scales (small inter-fibre spacing compared with construct dimensions) to derive macroscale equations governing the response of the composite to an applied load. This homogenised description reflects the orthotropic nature of the composite. To validate the model, solutions from finite element simulations of the macroscale, homogenised equations are compared to experimental data describing the unconfined compression of the fibre-reinforced hydrogels. The model is used to derive the bulk mechanical properties of a cylindrical construct of the composite material for a range of fibre spacings and to determine the local mechanical environment experienced by cells embedded within the construct.
This study assessed variation in coverage of maternal pertussis vaccination, introduced in England in October 2012 in response to a national outbreak, and a new infant rotavirus vaccination programme, implemented in July 2013. Vaccine eligible patients were included from national vaccine coverage datasets and covered April 2014 to March 2015 for pertussis and January 2014 to June 2016 for rotavirus. Vaccine coverage (%) was calculated overall and by NHS England Local Team (LT), ethnicity and Index of Multiple Deprivation (IMD) quintile, and compared using binomial regression. Compared with white-British infants, the largest differences in rotavirus coverage were in ‘other’, white-Irish and black-Caribbean infants (−13·9%, −12·1% and −10·7%, respectively), after adjusting for IMD and LT. The largest differences in maternal pertussis coverage were in black-other and black-Caribbean women (−16·3% and −15·4%, respectively). Coverage was lowest in London LT for both programmes. Coverage decreased with increasing deprivation and was 14·0% lower in the most deprived quintile compared with the least deprived for the pertussis programme and 4·4% lower for rotavirus. Patients’ ethnicity and deprivation were therefore predictors of coverage which contributed to, but did not wholly account for, geographical variation in coverage in England.
Conventionally perennial ryegrass evaluations are conducted under simulated grazing studies to identify varieties with the best phenotypic performance. However, cut-plot environments differ greatly to those experienced on commercial farms as varieties are not exposed to the same stress levels in test environments. It could be argued that plot-based testing regimes provide little direction to plant breeders in the development of advanced varieties. Varietal phenotypic performance needs to be quantified in ‘commercial’ situations. The objective of the current study was to evaluate the phenotypic performance of a range of perennial ryegrass varieties under commercial farm conditions. Monocultures of 11 Irish Recommended List perennial ryegrass varieties were sown on 66 commercial farms throughout Ireland where performance was evaluated over a 3-year period from 2013 to 2015, inclusive. A linear mixed model was used to quantify variety effects on grassland phenotypic performance characteristics. No significant variety effect was estimated for total, seasonal or silage herbage production. Despite the lack of variety effects, pairwise comparisons found significant performance differences between individual varieties. Grazed herbage yield is of primary importance and was shown to be correlated strongly with total production (0.71); Grazed herbage yield differed significantly by variety, with a range of 1927 kg dry matter (DM)/ha between the highest and lowest performing varieties. Sward quality (dry matter digestibility [DMD]) and density were influenced by variety with a range of 44 g/kg DM for DMD and 0.7 ground score units between the highest and lowest performing varieties. Results of the current study show that on-farm evaluation is effective in identifying the most suitable varieties for intensive grazing regimes, and the phenotypic variance identified among varieties performance for many traits should allow for improved genetic gain in areas such as DM production, persistence and grazing efficiency.
A 57-year-old female patient with a diagnosis of schizo-affective disorder since 1986 was commenced on clozapine due to persistent positive and negative psychotic symptoms in September 2014. After commencement of clozapine she was delusion free and demonstrated an improvement in negative symptoms. Three months after commencement of clozapine she developed a hypersensitivity reaction. Her symptoms continued to deteriorate despite being prescribed an anti-histamine. Clozapine was discontinued 6 days after the appearance of a generalised pruritic rash, as it was believed to be the probable cause. There was complete resolution of symptoms 1 week after discontinuation of clozapine. Clozapine was replaced with olanzapine and amisulpride. There has been no similar cutaneous or allergic reactions for the past 30 months.
The Solvency II Directive introduces the idea of a formal Actuarial Function to have responsibility over delivering the requirements of Article 48 of the Directive. Article 48 describes the responsibilities as being concerned with technical provisions, an opinion on reinsurance adequacy, an opinion on underwriting policy and contributing to the risk management system. Considerable documentation has been produced by the Prudential Regulation Authority (PRA), the Institute and Faculty of Actuaries (IFoA) and the European Insurance and Occupational Pensions Authority on the subject, much of it very recent to the publication of this paper. The purpose of this paper is to provide the reader with some practical insights and suggestions around addressing the requirements of Article 48 of the Solvency II Directive in general insurance firms, taking into consideration the publications of the aforementioned regulatory authorities. It is not our intention to give advice, nor to be seen to give advice, but rather to make suggestions and observations that we hope the reader will find useful. The Regulations lay down the tasks of the Actuarial Function, so insurers should consider the need for formal terms of reference, backed up by proportionate governance procedures. The Regulations also require the production of an Actuarial Function Report to document the tasks undertaken by the Actuarial Function and its results. Such a report can be an aggregate report, made up of individual component reports completed at suitable points in the Actuarial Function’s work cycle, so long as it reports on all the required tasks. The technical provisions section should cover at least all the areas laid down in the Delegated Acts. The opinions required covering reinsurance adequacy and underwriting policy are not formal “sign offs”, but contributions to the effective running of the insurer by applying the skills and knowledge of actuaries to areas for which they are not normally responsible. Again, the Delegated Acts mandate the minimum contribution the Actuarial Function should make. The responsibility for delivering the work of the Actuarial Function does not have to be given to a member of the IFoA; however, the PRA is going to require (at least) one person to be designated the “Chief Actuary”, defined as the person responsible for delivering the requirements of Article 48 of the Directive. In response, the IFoA has stated its intention to require its members holding the role of Chief Actuary, as defined by the PRA, to hold a practicing certificate. Any Actuarial Function will need to consider issues of governance, independence and conflicts of interests. The PRA intends to require the Actuarial Function to be independent of an insurer’s revenue-generating functions. In addition, normal good governance requires a degree of separation between those who perform Actuarial Function work and those who review and supervise it. There are numerous stakeholders in the Actuarial Function’s work. Some of these will rely on the output of the Actuarial Function, others will provide inputs to its work. Setting out stakeholder responsibilities clearly and in advance will be of vital importance. Good communication and coordination between these groups will be important to the efficient running of the insurer. Bringing together issues of governance, independence and meeting the Directive and regulators’ requirements will require a suitable organisational structure which will also need to consider practical issues, such as the availability of suitable staff. Many such arrangements may be possible, but all will require trading off advantages and disadvantages. The Actuarial Function is primarily about good practice and getting the most out of the actuarial skills available. For many insurers, meeting the requirements should not be unduly burdensome.
To examine the delivery and assessment of psychiatry at undergraduate level in the six medical schools in the Republic of Ireland offering a medical degree programme.
A narrative description of the delivery and assessment of psychiatry at undergraduate level by collaborative senior faculty members from all six universities in Ireland.
Psychiatry is integrated to varying degrees across all medical schools. Clinical experience in general adult psychiatry and sub-specialities is provided by each medical school; however, the duration of clinical attachment varies, and the provision of some sub-specialities (i.e. forensic psychiatry) is dependent on locally available resources. Five medical schools provide ‘live’ large group teaching sessions (lectures), and all medical schools provide an array of small group teaching sessions. Continuous assessment encompasses 10–35% of the total assessment marks, depending on the medical school. Only one medical school does not provide a clinical examination in the form of an Objective Structured Clinical Examination with viva examinations occurring at three medical schools.
Many similarities exist in relation to the delivery of psychiatry at undergraduate level in Ireland. Significant variability exists in relation to assessment with differences in continuous assessment, written and clinical exams and the use of vivas noted. The use of e-learning platforms has increased significantly in recent years, with their role envisaged to include cross-disciplinary teaching sessions and analysis of examinations and individual components within examinations which will help refine future examinations and enable greater sharing of resources between medical schools.
Between 1 January 2009 and 31 December 2012 in England, a total of 3717 cases were reported with evidence of Shiga toxin-producing E. coli (STEC) infection, and the crude incidence of STEC infection was 1·80/100 000 person-years. Incidence was highest in children aged 1–4 years (7·63/100 000 person-years). Females had a higher incidence of STEC than males [rate ratio (RR) 1·24, P < 0·001], and white ethnic groups had a higher incidence than non-white ethnic groups (RR 1·43, P < 0·001). Progression to haemolytic uraemic syndrome (HUS) was more frequent in females and children. Non-O157 STEC strains were associated with higher hospitalization and HUS rates than O157 STEC strains. In STEC O157 cases, phage type (PT) 21/28, predominantly indigenously acquired, was also associated with more severe disease than other PTs, as were strains encoding stx2 genes. Incidence of STEC was over four times higher in people residing in rural areas than urban areas (RR 4·39, P < 0·001). Exposure to livestock and/or their faeces was reported twice as often in cases living in rural areas than urban areas (P < 0·001). Environmental/animal contact remains an important risk factor for STEC transmission and is a significant driver in the burden of sporadic STEC infection. The most commonly detected STEC serogroup in England was O157. However, a bias in testing methods results in an unquantifiable under-ascertainment of non-O157 STEC infections. Implementation of PCR-based diagnostic methods designed to detect all STEC, to address this diagnostic deficit, is therefore important.
Adequate Zn and Mg intakes may be beneficial for the prevention and treatment of mental health problems, such as depression, anxiety and attention-deficit hyperactivity disorder. We aimed to investigate the prospective association between dietary intakes of Zn and Mg and internalising and externalising behaviour problems in a population-based cohort of adolescents.
Prospective analysis (general linear mixed models) of dietary intakes of Zn and Mg assessed using a validated FFQ and mental health symptoms assessed using the Youth Self-Report (YSR), adjusting for sex, physical activity, family income, supplement status, dietary misreporting, BMI, family functioning and energy intake.
Western Australian Pregnancy Cohort (Raine) Study.
Adolescents (n 684) at the 14- and 17-year follow-ups.
Higher dietary intake of Mg (per sd increase) was significantly associated with reduced externalising behaviours (β=−1·45; 95 % CI −2·40, −0·50; P=0·003). There was a trend towards reduced externalising behaviours with higher Zn intake (per sd increase; β=−0·73; 95 % CI −1·57, 0·10; P=0·085).
The study shows an association between higher dietary Mg intake and reduced externalising behaviour problems in adolescents. We observed a similar trend, although not statistically significant, for Zn intake. Randomised controlled trials are necessary to determine any benefit of micronutrient supplementation in the prevention and treatment of mental health problems in adolescents.
Recent randomized controlled trials suggest some efficacy for focused interventions in subjects at high risk (HR) for psychosis. However, treating HR subjects within the real-world setting of prodromal services is hindered by several practical problems that can significantly make an impact on the effect of focused interventions.
All subjects referred to Outreach and Support in South London (OASIS) and diagnosed with a HR state in the period 2001–2012 were included (n = 258). Exposure to focused interventions was correlated with sociodemographic and clinical characteristics at baseline. Their association with longitudinal clinical and functional outcomes was addressed at follow-up.
In a mean follow-up time of 6 years (s.d. = 2.5 years) a transition risk of 18% was observed. Of the sample, 33% were treated with cognitive behavioural therapy (CBT) only; 17% of subjects received antipsychotics (APs) in addition to CBT sessions. Another 17% of subjects were prescribed with antidepressants (ADs) in addition to CBT. Of the sample, 20% were exposed to a combination of interventions. Focused interventions had a significant relationship with transition to psychosis. The CBT + AD intervention was associated with a reduced risk of transition to psychosis, as compared with the CBT + AP intervention (hazards ratio = 0.129, 95% confidence interval 0.030–0.565, p = 0.007).
There were differential associations with transition outcome for AD v. AP interventions in addition to CBT in HR subjects. These effects were not secondary to baseline differences in symptom severity.
Many serogroups of Shiga toxin-producing Escherichia coli (STEC) other than serogroup O157 (non-O157 STEC), for example STEC O26:H11, are highly pathogenic and capable of causing haemolytic uraemic syndrome. A recent increase in non-O157 STEC cases identified in England, resulting from a change in the testing paradigm, prompted a review of the current methods available for detection and typing of non-O157 STEC for surveillance and outbreak investigations. Nineteen STEC O26:H11 strains, including four from a nursery outbreak were selected to assess typing methods. Serotyping and multilocus sequence typing were not able to discriminate between the stx-producing strains in the dataset. However, genome sequencing provided rapid and robust confirmation that isolates of STEC O26:H11 associated with a nursery outbreak were linked at the molecular level, had a common source and were distinct from the other strains analysed. Virulence gene profiling of DNA extracted from a polymerase chain reaction (PCR)-positive/culture-negative faecal specimen from a case that was epidemiologically linked to the STEC O26:H11 nursery outbreak, provided evidence at the molecular level to support that link. During this study, we describe the utility of PCR and the genome sequencing approach in facilitating surveillance and enhancing the response to outbreaks of non-O157 STEC.
Patients with anxiety disorders suffer marked functional impairment in their activities of daily living. Many studies have documented that improvements in anxiety symptom severity predict functioning improvements. However, no studies have investigated how improvements in functioning simultaneously predict symptom reduction. We hypothesized that symptom levels at a given time point will predict functioning at the subsequent time point, and simultaneously that functioning at a given time point will predict symptom levels at a subsequent time point.
Patients were recruited from primary-care centers for the Coordinated Anxiety Learning and Management (CALM) study and were randomized to receive either computer-assisted cognitive-behavioral therapy and/or medication management (ITV) or usual care (UC). A cross-lagged panel design examined the relationship between functional impairment and anxiety and depression symptom severity at baseline, 6-, 12-, and 18-month follow-up assessments.
Prospective prediction of functioning from symptoms and symptoms from functioning were both important in modeling these associations. Anxiety and depression predicted functioning as strongly as functioning predicted anxiety and depression. There were some differences in these associations between UC and ITV. Where differences emerged, the UC group was best modeled with prospective paths predicting functioning from symptoms, whereas symptoms and functioning were both important predictors in the ITV group.
Treatment outcome is best captured by measures of functional impairment as well as symptom severity. Implications for treatment are discussed, as well as future directions of research.
The amygdala and subgenual anterior cingulate cortex (sACC) are key brain regions for the generation of negative affect. In this longitudinal fMRI study of adolescents we investigated how amygdala–sACC connectivity was correlated with negative affectivity (NA) both cross-sectionally and longitudinally, and examined its relationship to the onset of first-episode depression.
Fifty-six adolescents who were part of a larger longitudinal study of adolescent development were included. They had no history of mental illness at the time of their baseline scan (mean age 16.5 years) and had a follow-up scan 2 years later (mean age 18.8 years). We used resting-state functional-connectivity MRI to investigate whether cross-sectional and change measures of amygdala–sACC connectivity were (i) correlated with NA and its change over time, and (ii) related to the onset of first-episode depression.
The magnitude of amygdala connectivity with sACC showed significant positive correlation with NA at both time-points. Further analysis confirmed that change in amygdala–sACC connectivity between assessments was correlated with change in NA. Eight participants developed a first episode of depression between the baseline and follow-up assessments: they showed increased amygdala–sACC connectivity at follow-up.
Amygdala–sACC connectivity is associated with NA in adolescence, with change in connectivity between these regions showing positive correlation with change in NA. Our observation that the onset of depression was associated with an increase in connectivity between the regions provides support for the neurobiological ‘scar’ hypothesis of depression.
This study sought to ascertain the prevalence rates and risk factors for a range of mental health difficulties, including suicidal ideation/self-harm among 16 and 17-year-old rural Irish adolescents, a vulnerable group in transition from childhood to adulthood.
Adolescents (n=237) took part in this cross-sectional study. Participants completed a questionnaire compendium consisting of generic questions on demographic information, use of mental health services and four normed questionnaires: The Youth Self-Report, the Children’s Depression Inventory, the Coping Inventory for Stressful Situations-Adolescent and The Family Assessment Device.
We found that 16.9% of adolescents reported clinically significant mental health difficulties. Significant gender differences were found on internalising and externalising difficulties. There were no gender differences in suicidal ideation or self-harm. Only 3.4% of adolescents were receiving professional help for mental health difficulties. Multiple regression analyses revealed that family dysfunction, emotion-focussed coping and poor academic competence were significant predictors of poorer mental health difficulties in both genders. Family dysfunction was the strongest predictor of mental health difficulties in males. Among females, emotion-focussed coping was the strongest predictor of internalising difficulties and depression. Social diversion (social support) was predictive of less internalising difficulties and depression for females.
The study shows that a significant number of Irish 16 and 17 year olds have mental health difficulties, yet very few are receiving treatment. Emotion-focussed coping, family dysfunction, poor academic competence and less social support were important predictors of mental health difficulties. A new finding is the stronger association that family dysfunction has with poorer mental health in males than females, when controlling for academic competence and coping skills. The findings may have implications for psychological interventions.