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We describe the design and deployment of GREENBURST, a commensal Fast Radio Burst (FRB) search system at the Green Bank Telescope. GREENBURST uses the dedicated L-band receiver tap to search over the 960–1 920 MHz frequency range for pulses with dispersion measures out to
. Due to its unique design, GREENBURST is capable of conducting searches for FRBs when the L-band receiver is not being used for scheduled observing. This makes it a sensitive single pixel detector capable of reaching deeper in the radio sky. While single pulses from Galactic pulsars and rotating radio transients will be detectable in our observations, and will form part of the database we archive, the primary goal is to detect and study FRBs. Based on recent determinations of the all-sky rate, we predict that the system will detect approximately one FRB for every 2–3 months of continuous operation. The high sensitivity of GREENBURST means that it will also be able to probe the slope of the FRB fluence distribution, which is currently uncertain in this observing band.
Hendra virus (HeV) continues to cause fatal infection in horses and threaten infection in close-contact humans in eastern Australia. Species of Pteropus bats (flying-foxes) are the natural reservoir of the virus. We caught and sampled flying-foxes from a multispecies roost in southeast Queensland, Australia on eight occasions between June 2013 and June 2014. The effects of sample date, species, sex, age class, body condition score (BCS), pregnancy and lactation on HeV antibody prevalence, log-transformed median fluorescent intensity (lnMFI) values and HeV RNA status were assessed using unbalanced generalised linear models. A total of 1968 flying-foxes were sampled, comprising 1012 Pteropus alecto, 742 P. poliocephalus and 214 P. scapulatus. Sample date, species and age class were each statistically associated with HeV RNA status, antibody status and lnMFI values; BCS was statistically associated with HeV RNA status and antibody status. The findings support immunologically naïve sub-adult P. alecto playing an important role in maintaining HeV infection at a population level. The biological significance of the association between BCS and HeV RNA status, and BCS and HeV antibody status, is less clear and warrants further investigation. Contrary to previous studies, we found no direct association between HeV infection and pregnancy or lactation. The findings in P. poliocephalus suggest that HeV exposure in this species may not result in systemic infection and virus excretion, or alternatively, may reflect assay cross-reactivity with another (unidentified) henipavirus.
Background:ATP8A2 mutations have only recently been associated with human disease. We present the clinical features from the largest cohort of patients with this disorder reported to date. Methods: An observational study of 9 unreported and 2 previously reported patients with biallelic ATP8A2 mutations was carried out at multiple centres. Results: The mean age of the cohort was 9.4 years old (range: 2.5-28 yrs). All patients demonstrated developmental delay, severe hypotonia and movement disorders: chorea/choreoathetosis (100%), dystonia (27%) or facial dyskinesia (18%). Hypotonia was apparent at birth (70%) or before 6 months old (100%). Optic atrophy was observed in 75% of patients who had a funduscopic examination. MRI of the brain was normal for most patients with a small proportion showing mild cortical atrophy (30%), delayed myelination (20%) and/or hypoplastic optic nerves (20%). Epilepsy was seen in two older patients. Conclusions:ATP8A2 gene mutations have emerged as a cause of a novel phenotype characterized by developmental delay, severe hypotonia and hyperkinetic movement disorders. Optic atrophy is common and may only become apparent in the first few years of life, necessitating repeat ophthalmologic evaluation. Early recognition of the cardinal features of this condition will facilitate diagnosis of this disorder.
Prior research has documented shared heritable contributions to non-suicidal self-injury (NSSI) and suicidal ideation (SI) as well as NSSI and suicide attempt (SA). In addition, trauma exposure has been implicated in risk for NSSI and suicide. Genetically informative studies are needed to determine common sources of liability to all three self-injurious thoughts and behaviors, and to clarify the nature of their associations with traumatic experiences.
Multivariate biometric modeling was conducted using data from 9526 twins [59% female, mean age = 31.7 years (range 24–42)] from two cohorts of the Australian Twin Registry, some of whom also participated in the Childhood Trauma Study and the Nicotine Addiction Genetics Project.
The prevalences of high-risk trauma exposure (HRT), NSSI, SI, and SA were 24.4, 5.6, 27.1, and 4.6%, respectively. All phenotypes were moderately to highly correlated. Genetic influences on self-injurious thoughts and behaviors and HRT were significant and highly correlated among men [rG = 0.59, 95% confidence interval (CI) (0.37–0.81)] and women [rG = 0.56 (0.49–0.63)]. Unique environmental influences were modestly correlated in women [rE = 0.23 (0.01–0.45)], suggesting that high-risk trauma may confer some direct risk for self-injurious thoughts and behaviors among females.
Individuals engaging in NSSI are at increased risk for suicide, and common heritable factors contribute to these associations. Preventing trauma exposure may help to mitigate risk for self-harm and suicide, either directly or indirectly via reductions in liability to psychopathology more broadly. In addition, targeting pre-existing vulnerability factors could significantly reduce risk for life-threatening behaviors among those who have experienced trauma.
Cortical glutamatergic dysfunction is thought to be fundamental for psychosis development, and may lead to structural degeneration through excitotoxicity. Glutamate levels have been related to gray matter volume (GMV) alterations in people at ultra-high risk of psychosis, and we previously reported GMV changes in individuals with high schizotypy (HS), which refers to the expression of schizophrenia-like characteristics in healthy people. This study sought to examine whether GMV changes in HS subjects are related to glutamate levels.
We selected 22 healthy subjects with HS and 23 healthy subjects with low schizotypy (LS) based on their rating on a self-report questionnaire for psychotic-like experiences. Glutamate levels were measured in the bilateral anterior cingulate cortex (ACC) using proton magnetic resonance spectroscopy, and GMV was assessed using voxel-based morphometry.
Subjects with HS showed GMV decreases in the rolandic operculum/superior temporal gyrus (pFWE = 0.045). Significant increases in GMV were also detected in HS, in the precuneus (pFWE = 0.043), thereby replicating our previous finding in a separate cohort, as well as in the ACC (pFWE = 0.041). While the HS and LS groups did not differ in ACC glutamate levels, in HS subjects ACC glutamate was negatively correlated with ACC GMV (pFWE = 0.026). Such association was absent in LS.
Our study shows that GMV findings in schizotypy are related to glutamate levels, supporting the hypothesis that glutamatergic function may lead to structural changes associated with the expression of psychotic-like experiences.
Traumatic events are associated with increased risk of psychotic experiences, but it is unclear whether this association is explained by mental disorders prior to psychotic experience onset.
To investigate the associations between traumatic events and subsequent psychotic experience onset after adjusting for post-traumatic stress disorder and other mental disorders.
We assessed 29 traumatic event types and psychotic experiences from the World Mental Health surveys and examined the associations of traumatic events with subsequent psychotic experience onset with and without adjustments for mental disorders.
Respondents with any traumatic events had three times the odds of other respondents of subsequently developing psychotic experiences (OR=3.1, 95% CI 2.7–3.7), with variability in strength of association across traumatic event types. These associations persisted after adjustment for mental disorders.
Exposure to traumatic events predicts subsequent onset of psychotic experiences even after adjusting for comorbid mental disorders.
Violence exposure during childhood is common and associated with poor cognitive and academic functioning. However, little is known about how violence exposure influences cognitive processes that might contribute to these disparities, such as working memory, or their neural underpinnings, particularly for cognitive processes that occur in emotionally salient contexts. We address this gap in a sample of 54 participants aged 8 to 19 years (50% female), half with exposure to interpersonal violence. Participants completed a delayed match to sample task for emotional faces while undergoing functional magnetic resonance imaging scanning. Violence-exposed youth performed worse than controls on happy and neutral, but not angry, trials. In whole-brain analysis, violence-exposed youth had reduced activation in the left middle frontal gyrus and right intraparietal sulcus during encoding and the left superior temporal sulcus and temporal–parietal junction during retrieval compared to control youth. Reduced activation in the left middle frontal gyrus during encoding and the left superior temporal sulcus during retrieval mediated the association between violence exposure and task performance. Violence exposure influences the frontoparietal network that supports working memory as well as regions involved in facial processing during working memory for emotional stimuli. Reduced neural recruitment in these regions may explain atypical patterns of cognitive processing seen among violence-exposed youth, particularly within emotional contexts.
Although childhood adversities are known to predict increased risk of post-traumatic stress disorder (PTSD) after traumatic experiences, it is unclear whether this association varies by childhood adversity or traumatic experience types or by age.
To examine variation in associations of childhood adversities with PTSD according to childhood adversity types, traumatic experience types and life-course stage.
Epidemiological data were analysed from the World Mental Health Surveys (n = 27017).
Four childhood adversities (physical and sexual abuse, neglect, parent psychopathology) were associated with similarly increased odds of PTSD following traumatic experiences (odds ratio (OR)=1.8), whereas the other eight childhood adversities assessed did not predict PTSD. Childhood adversity–PTSD associations did not vary across traumatic experience types, but were stronger in childhood-adolescence and early-middle adulthood than later adulthood.
Childhood adversities are differentially associated with PTSD, with the strongest associations in childhood-adolescence and early-middle adulthood. Consistency of associations across traumatic experience types suggests that childhood adversities are associated with generalised vulnerability to PTSD following traumatic experiences.
In Ireland, National Clinical Programmes are being established to improve and standardise patient care throughout the Health Service Executive. In line with internationally recognised guidelines on the treatment of first episode psychosis the Early Intervention in Psychosis (EIP) programme is being drafted with a view to implementation by mental health services across the country. We undertook a review of patients presenting with a first episode of psychosis to the Dublin Southwest Mental Health Service before the implementation of the EIP. This baseline information will be used to measure the efficacy of our EIP programme.
Patients who presented with a first episode psychosis were retrospectively identified through case note reviews and consultation with treating teams. We gathered demographic and clinical information from patients as well as data on treatment provision over a 2-year period from the time of first presentation. Data included age at first presentation, duration of untreated psychosis, diagnosis, referral source, antipsychotic prescribing rates and dosing, rates of provision of psychological interventions and standards of physical healthcare monitoring. Outcome measures with regards to rates of admission over a 2-year period following initial presentation were also recorded.
In total, 66 cases were identified. The majority were male, single, unemployed and living with their family or spouse. The mean age at first presentation was 31 years with a mean duration of untreated psychosis of 17 months. Just under one-third were diagnosed with schizophrenia. Approximately half of the patients had no contact with a health service before presentation. The majority of patients presented through the emergency department. Two-thirds of all patients had a hospital admission within 2 years of presentation and almost one quarter of patients had an involuntary admission. The majority of patients were prescribed antipsychotic doses within recommended British National Formulary guidelines. Most patients received individual support through their keyworker and family intervention was provided in the majority of cases. Only a small number received formal Cognitive-Behavioural Therapy. Physical healthcare monitoring was insufficiently recorded in the majority of patients.
There is a shortage of information on the profile and treatment of patients presenting with a first episode of psychosis in Ireland. This baseline information is important in evaluating the efficacy of any new programme for this patient group. Many aspects of good practice were identified within the service in particular with regards to the appropriate prescribing of antipsychotic medication and the rates of family intervention. Deficiencies remain however in the monitoring of physical health and the provision of formal psychological interventions to patients. With the implementation of an EIP programme it is hoped that service provision would improve nationwide and to internationally recognised standards.
Here, we present initial results from the ALFABURST radio transient survey, which is currently running in a commensal mode with the ALFA receiver at the Arecibo telescope. We observed for a total of 1400 hours and have detected single pulses from known pulsars but did not detect any FRBs. The non-detection of FRBs is consistent with the current FRB sky rates.
Traumatic events are common globally; however, comprehensive population-based cross-national data on the epidemiology of posttraumatic stress disorder (PTSD), the paradigmatic trauma-related mental disorder, are lacking.
Data were analyzed from 26 population surveys in the World Health Organization World Mental Health Surveys. A total of 71 083 respondents ages 18+ participated. The Composite International Diagnostic Interview assessed exposure to traumatic events as well as 30-day, 12-month, and lifetime PTSD. Respondents were also assessed for treatment in the 12 months preceding the survey. Age of onset distributions were examined by country income level. Associations of PTSD were examined with country income, world region, and respondent demographics.
The cross-national lifetime prevalence of PTSD was 3.9% in the total sample and 5.6% among the trauma exposed. Half of respondents with PTSD reported persistent symptoms. Treatment seeking in high-income countries (53.5%) was roughly double that in low-lower middle income (22.8%) and upper-middle income (28.7%) countries. Social disadvantage, including younger age, female sex, being unmarried, being less educated, having lower household income, and being unemployed, was associated with increased risk of lifetime PTSD among the trauma exposed.
PTSD is prevalent cross-nationally, with half of all global cases being persistent. Only half of those with severe PTSD report receiving any treatment and only a minority receive specialty mental health care. Striking disparities in PTSD treatment exist by country income level. Increasing access to effective treatment, especially in low- and middle-income countries, remains critical for reducing the population burden of PTSD.
Baltinglass is a multi-chamber Neolithic passage tomb in Co. Wicklow, Ireland, excavated in the 1930s. This paper presents the results of a radiocarbon dating programme on charred wheat grains and hazelnut shell found underlying the cairn, and on cremated human bone found within and near two of the monument’s five chambers. The results are surprising, in that three of the six determinations on calcined bone pre-date by one or two centuries the charred cereals and hazelnut shells sealed under the cairn, dating to c. 3600–3400 cal bc. Of the remaining three bone results, one is coeval with the charred plant remains, while the final two can be placed in the period 3300/3200–2900 cal bc, that is more traditionally associated with developed passage tombs. A suggested sequence of construction is presented beginning with a simple tomb lacking a cairn, followed by a burning event – perhaps a ritual preparation of the ground – involving the deposition of cereal grains and other materials, very rapidly and intentionally sealed under a layer of clay, in turn followed by at least two phases involving the construction of more substantial chambers and associated cairns. What was already a complex funerary monument has proven to be even more complex, with a history spanning at least six centuries.
Although there is robust evidence linking childhood adversities (CAs) and an increased risk for psychotic experiences (PEs), little is known about whether these associations vary across the life-course and whether mental disorders that emerge prior to PEs explain these associations.
We assessed CAs, PEs and DSM-IV mental disorders in 23 998 adults in the WHO World Mental Health Surveys. Discrete-time survival analysis was used to investigate the associations between CAs and PEs, and the influence of mental disorders on these associations using multivariate logistic models.
Exposure to CAs was common, and those who experienced any CAs had increased odds of later PEs [odds ratio (OR) 2.3, 95% confidence interval (CI) 1.9–2.6]. CAs reflecting maladaptive family functioning (MFF), including abuse, neglect, and parent maladjustment, exhibited the strongest associations with PE onset in all life-course stages. Sexual abuse exhibited a strong association with PE onset during childhood (OR 8.5, 95% CI 3.6–20.2), whereas Other CA types were associated with PE onset in adolescence. Associations of other CAs with PEs disappeared in adolescence after adjustment for prior-onset mental disorders. The population attributable risk proportion (PARP) for PEs associated with all CAs was 31% (24% for MFF).
Exposure to CAs is associated with PE onset throughout the life-course, although sexual abuse is most strongly associated with childhood-onset PEs. The presence of mental disorders prior to the onset of PEs does not fully explain these associations. The large PARPs suggest that preventing CAs could lead to a meaningful reduction in PEs in the population.
Because individuals develop dementia as a manifestation of neurodegenerative or neurovascular disorder, there is a need to develop reliable approaches to their identification. We are undertaking an observational study (Ontario Neurodegenerative Disease Research Initiative [ONDRI]) that includes genomics, neuroimaging, and assessments of cognition as well as language, speech, gait, retinal imaging, and eye tracking. Disorders studied include Alzheimer’s disease, amyotrophic lateral sclerosis, frontotemporal dementia, Parkinson’s disease, and vascular cognitive impairment. Data from ONDRI will be collected into the Brain-CODE database to facilitate correlative analysis. ONDRI will provide a repertoire of endophenotyped individuals that will be a unique, publicly available resource.
We report on new pulsars discovered in Arecibo drift-scan datA. Processing of 2200 deg2 of data has resulted in the detection of 41 known and 12 new pulsars. New pulsars include two millisecond pulsars, one solitary and one binary recycled pulsar, and one pulsar with very unusual pulse profile morphology and complex drifting subpulse behavior.
PSRs J1847–0130 and J1718–37184 have inferred surface dipole magnetic fields greater than those of any other known pulsars and well above the “quantum critical field” above which some models predict radio emission should not occur. These fields are similar to those of the anomalous X-ray pulsars (AXPs), which growing evidence suggests are “magnetars”. The lack of AXP-like X-ray emission from these radio pulsars (and the non-detection of radio emission from the AXPs) creates new challenges for understanding pulsar emission physics and the relationship between these classes of apparently young neutron stars.
Hendra virus (HeV) was first described in 1994 in an outbreak of acute and highly lethal disease in horses and humans in Australia. Equine cases continue to be diagnosed periodically, yet the predisposing factors for infection remain unclear. We undertook an analysis of equine submissions tested for HeV by the Queensland government veterinary reference laboratory over a 20-year period to identify and investigate any patterns. We found a marked increase in testing from July 2008, primarily reflecting a broadening of the HeV clinical case definition. Peaks in submissions for testing, and visitations to the Government HeV website, were associated with reported equine incidents. Significantly differing between-year HeV detection rates in north and south Queensland suggest a fundamental difference in risk exposure between the two regions. The statistical association between HeV detection and stockhorse type may suggest that husbandry is a more important risk determinant than breed per se. The detection of HeV in horses with neither neurological nor respiratory signs poses a risk management challenge for attending veterinarians and laboratory staff, reinforcing animal health authority recommendations that appropriate risk management strategies be employed for all sick horses, and by anyone handling sick horses or associated biological samples.