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Breakthrough Listen is a 10-yr initiative to search for signatures of technologies created by extraterrestrial civilisations at radio and optical wavelengths. Here, we detail the digital data recording system deployed for Breakthrough Listen observations at the 64-m aperture CSIRO Parkes Telescope in New South Wales, Australia. The recording system currently implements two modes: a dual-polarisation, 1.125-GHz bandwidth mode for single-beam observations, and a 26-input, 308-MHz bandwidth mode for the 21-cm multibeam receiver. The system is also designed to support a 3-GHz single-beam mode for the forthcoming Parkes ultra-wideband feed. In this paper, we present details of the system architecture, provide an overview of hardware and software, and present initial performance results.
There is a genetic contribution to the risk of suicide, but sparse prior research on the genetics of suicidal ideation.
Active and passive suicidal ideation were assessed in a Sri Lankan population-based twin registry (n = 3906 twins) and a matched non-twin sample (n = 2016). Logistic regression models were used to examine associations with socio-demographic factors, environmental exposures and psychiatric symptoms. The heritability of suicidal ideation was assessed using structural equation modelling.
The lifetime prevalence of any suicidal ideation was 13.0% (11.7–14.3%) for men; 21.8% (20.3–23.2%) for women, with no significant difference between twins and non-twins. Factors that predicted suicidal ideation included female gender, termination of marital relationship, low education level, urban residence, losing a parent whilst young, low standard of living and stressful life events in the preceding 12 months. Suicidal ideation was strongly associated with depression, but also with abnormal fatigue and alcohol and tobacco use. The best fitting structural equation model indicated a substantial contribution from genetic factors (57%; CI 47–66) and from non-shared environmental factors (43%; CI 34–53) in both men and women. In women this genetic component was largely mediated through depression, but in men there was a significant heritable component to suicidal ideation that was independent of depression.
These are the first results to show a genetic contribution to suicidal ideation that is independent of depression outside of a high-income country. These phenomena may be generalizable, because previous research highlights similarities between the aetiology of mental disorders in Sri Lanka and higher-income countries.
The ‘voice quality symbols’ (VoQS) transcription system for voice quality was introduced some 20 years ago, and no major revision has been undertaken since then. In this account we describe the first major revision of the VoQS chart, these changes being mostly in the form of additions to the section on phonation types, but include also changes to the layout of the supralaryngeal settings section. These reflect recent developments in the understanding of the physiological underpinnings of sounds produced in the larynx including certain phonation types.
Only a minority of trauma-exposed individuals go on to develop post traumatic stress disorder (PTSD). Previous studies in high-income countries suggest that maladaptive family functioning adversities (MFFA) in childhood may partially ex-plain individual variation in vulnerability to PTSD following trauma. We test in a lower middle income setting (Sri Lanka) whether: (1) MFFA moderates the association between exposure to trauma and later (a) PTSD (b) other psychiatric diagnoses; (2) any moderation by MFFA is explained by experiences of interpersonal violence, cumulative trauma exposure or other psychopathology.
We conducted a population study of 3995 twins and 2019 singletons residing in Colombo, Sri Lanka. Participants completed the composite international diagnostic interview, including nine traumatic exposures and a questionnaire on MFFA.
In total, 23.4% of participants reported exposure to MFFA. We found that (1) MFFA moderates the association between trauma exposure and both (a) PTSD and (b) non-PTSD diagnosis. (2) This was not explained by interpersonal violence, cumulative trauma exposure or other psychopathology.
In our sample MFFA moderates the association between trauma and PTSD, and the association between trauma and non-PTSD psychopathology.
Bornaviruses cause neurologic diseases in several species of birds, especially parrots, waterfowl and finches. The characteristic lesions observed in these birds include encephalitis and gross dilatation of the anterior stomach — the proventriculus. The disease is thus known as proventricular dilatation disease (PDD). PDD is characterized by extreme proventricular dilatation, blockage of the passage of digesta and consequent death by starvation. There are few clinical resemblances between this and the bornaviral encephalitides observed in mammals. Nevertheless, there are common virus-induced pathogenic pathways shared across this disease spectrum that are explored in this review. Additionally, a review of the literature relating to gastroparesis in humans and the control of gastric mobility in mammals and birds points to several plausible mechanisms by which bornaviral infection may result in extreme proventricular dilatation.
Public health monitoring is commonly undertaken in social media but has never been combined with data analysis from electronic health records. This study aimed to investigate the relationship between the emergence of novel psychoactive substances (NPS) in social media and their appearance in a large mental health database.
Insufficient numbers of mentions of other NPS in case records meant that the study focused on mephedrone. Data were extracted on the number of mephedrone (i) references in the clinical record at the South London and Maudsley NHS Trust, London, UK, (ii) mentions in Twitter, (iii) related searches in Google and (iv) visits in Wikipedia. The characteristics of current mephedrone users in the clinical record were also established.
Increased activity related to mephedrone searches in Google and visits in Wikipedia preceded a peak in mephedrone-related references in the clinical record followed by a spike in the other 3 data sources in early 2010, when mephedrone was assigned a ‘class B’ status. Features of current mephedrone users widely matched those from community studies.
Combined analysis of information from social media and data from mental health records may assist public health and clinical surveillance for certain substance-related events of interest. There exists potential for early warning systems for health-care practitioners.
We describe the performance of the Boolardy Engineering Test Array, the prototype for the Australian Square Kilometre Array Pathfinder telescope. Boolardy Engineering Test Array is the first aperture synthesis radio telescope to use phased array feed technology, giving it the ability to electronically form up to nine dual-polarisation beams. We report the methods developed for forming and measuring the beams, and the adaptations that have been made to the traditional calibration and imaging procedures in order to allow BETA to function as a multi-beam aperture synthesis telescope. We describe the commissioning of the instrument and present details of Boolardy Engineering Test Array’s performance: sensitivity, beam characteristics, polarimetric properties, and image quality. We summarise the astronomical science that it has produced and draw lessons from operating Boolardy Engineering Test Array that will be relevant to the commissioning and operation of the final Australian Square Kilometre Array Path telescope.
A simple model is presented for electron acceleration in extragalactic radio sources with two hot spots. The effect of diffusive shock acceleration by multiple shocks is calculated numerically, with adiabatic and synchrotron losses included. It is found for the sources 3C 20 and 3C 268·4 that a consistent set of model parameters exists which reproduce the observations. The model fails to reproduce the observations for the source 3C 196.
Mood instability is an important problem but has received relatively little research attention. Natural language processing (NLP) is a novel method, which can used to automatically extract clinical data from electronic health records (EHRs).
To extract mood instability data from EHRs and investigate its impact on people with mental health disorders.
Data on mood instability were extracted using NLP from 27,704 adults receiving care from the South London and Maudsley NHS Foundation Trust (SLaM) for affective, personality or psychotic disorders. These data were used to investigate the association of mood instability with different mental disorders and with hospitalisation and treatment outcomes.
Mood instability was documented in 12.1% of people included in the study. It was most frequently documented in people with bipolar disorder (22.6%), but was also common in personality disorder (17.8%) and schizophrenia (15.5%). It was associated with a greater number of days spent in hospital (B coefficient 18.5, 95% CI 12.1–24.8), greater frequency of hospitalisation (incidence rate ratio 1.95, 1.75–2.17), and an increased likelihood of prescription of antipsychotics (2.03, 1.75–2.35).
Using NLP, it was possible to identify mood instability in a large number of people, which would otherwise not have been possible by manually reading clinical records. Mood instability occurs in a wide range of mental disorders. It is generally associated with poor clinical outcomes. These findings suggest that clinicians should screen for mood instability across all common mental health disorders. The data also highlight the utility of NLP for clinical research.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
The last decade has given rise to several tensions between calculated and (sometimes indirectly) measured stellar opacities. I discuss the current and future capacity for the asteroseismology of B-type oscillators (slowly-pulsating B-type stars and β Cepheids) and main-sequence solar-like oscillators to test stellar opacities. I briefly highlight two methods by which the B-type oscillators already constrain opacities, though they do not yet identify a superior set of tables. I then consider how the main-sequence solar-like oscillators might also test opacities, using the 16 Cygni system as an example. There are currently greater uncertainties than the opacities (in this example, the atmospheric structure) but many of these will be separately constrained in the near future.
Background: To date, no physical activity (PA) questionnaires intended for primary care have been compared against a criterion measure of PA and current (2008) aerobic PA recommendations of the American College of Sports Medicine/American Heart Association (ACSM/AHA). Aim: This study evaluated preliminary evidence for criterion validity of two brief (<1 min) PA questionnaires with accelerometry, and their ability to identify if individuals meet ACSM/AHA PA recommendations. Methods: 45 health clinic staff wore an accelerometer for seven consecutive days and afterwards completed two brief PA questionnaires, the Physical Activity Vital Sign (PAVS), and the Speedy Nutrition and Physical Activity Assessment (SNAP). Agreement and descriptive statistics were calculated between the PAVS or SNAP and accelerometry in order to measure each questionnaire’s ability to quantify the number of days participants achieved ⩾30 min of moderate–vigorous PA (MVPA) performed in bouts of ⩾10 continuous minutes. Participants with <5 days of ⩾30 bout-min of MVPA were considered insufficiently active according to PA recommendations. Findings: There was a significant positive correlation between number of days with ⩾30 bout-min MVPA and the PAVS (r=0.52, P<0.001), and SNAP (r=0.31, P<0.05). The PAVS had moderate agreement with accelerometry for identifying if individuals met or did not meet PA recommendations (κ=0.46, P<0.001), whereas SNAP had poor agreement (κ=0.12, P<0.05). Conclusions: This study provides preliminary evidence of criterion validity of the PAVS and SNAP with accelerometry and agreement identifying if respondents meet current (2008) ACSM/AHA aerobic PA recommendations. The PAVS and SNAP should be evaluated further for repeatability, and in populations varying in PA levels, age, gender, and ethnicity.
High-quality data from space-based observatories present an opportunity to fit stellar models to observations of individually-identified oscillation frequencies, not just the large and small frequency separations. But such fits require the evaluation of a large number of accurate stellar models, which remains expensive. Here, we show that global-mode oscillation frequencies interpolated in a grid of stellar models are precise and accurate, at least in the neighbourhood of a solar model.
Short sleep duration is associated with obesity in young children. This study develops the hypothesis that parental rules play a role in this association. Participants were 3-year-old children and their parents, recruited at nursery schools in socioeconomically deprived and non-deprived areas of a North-East England town. Parents were interviewed to assess their use of sleep, television-viewing and dietary rules, and given diaries to document their child's sleep for 4 days/5 nights. Children were measured for height, weight, waist circumference and triceps and subscapular skinfold thicknesses. One-hundred and eight families participated (84 with complete sleep data and 96 with complete body composition data). Parental rules were significantly associated together, were associated with longer night-time sleep and were more prevalent in the non-deprived-area compared with the deprived-area group. Television-viewing and dietary rules were associated with leaner body composition. Parental rules may in part confound the association between night-time sleep duration and obesity in young children, as rules cluster together across behavioural domains and are associated with both sleep duration and body composition. This hypothesis should be tested rigorously in large representative samples.
The mechanisms that contribute to emotion dysregulation in anxiety disorders are not well understood. Two common disorders, generalized anxiety disorder (GAD) and panic disorder (PD), were examined to test the hypothesis that both disorders are characterized by hypo-activation in prefrontal cortex (PFC) during emotion regulation. A competing hypothesis that GAD in particular is characterized by PFC hyper-activation during emotion regulation (reflecting overactive top-down control) was also evaluated.
Twenty-two medication-free healthy control (HC), 23 GAD, and 18 PD participants underwent functional magnetic resonance imaging (fMRI) during a task that required them to reappraise (i.e. reduce) or maintain emotional responses to negative images.
GAD participants reported the least reappraisal use in daily life, and reappraisal use was inversely associated with anxiety severity and functional impairment in these participants. During fMRI, HCs demonstrated greater activation during both reappraisal and maintenance than either GAD or PD participants (who did not differ) in brain areas important for emotion regulation (e.g. dorsolateral and dorsomedial PFC). Furthermore, across all anxious participants, activation during reappraisal in dorsolateral and dorsomedial PFC was inversely associated with anxiety severity and functional impairment.
Emotion dysregulation in GAD and PD may be the consequence of PFC hypo-activation during emotion regulation, consistent with insufficient top-down control. The relationship between PFC hypo-activation and functional impairment suggests that the failure to engage PFC during emotion regulation may be part of the critical transition from dispositionally high anxiety to an anxiety disorder.
Background: Somatic symptoms often co-occur with psychological symptoms but this overlap is poorly understood. Some aspects of this overlap differ in the South Asian context, but it is not clear whether this is a reporting effect or an underlying difference in experienced illness. Methods: Home interviews were administered to 4,024 twins randomly selected from a population-based twin register in the Colombo district of Sri Lanka (the CoTASS study). These included assessments of psychological, somatic and fatigue symptoms. The data were analyzed using factor analytic and quantitative genetic approaches. Results: Confirmatory factor analysis showed that the symptoms from the three scales represented three separate dimensions, rather than all tapping into a single dimension. However, familial correlations among the data were most consistent with a common pathway model. This implies that a portion of the underlying vulnerability is common across psychological, fatigue and somatic symptoms. There were sex differences in the etiology of this model, with shared environmental and genetic influences playing different roles in men and women. Conclusions: There is a complex etiological relationship between psychological, fatigue and somatic symptoms. This is similar in Sri Lanka to Western countries, but there may be a greater influence from the family environment, suggesting that care needs to be taken when generalizing research findings between countries. People who complain of certain fatigue or somatic symptoms may well also have psychological symptoms, or may have genetic or environmental vulnerabilities to such problems.
Fatigue is a common symptom in Western high-income countries but is often medically unexplained and little is known about its presentation in other populations.
To explore the epidemiology and aetiology of fatigue in Sri Lanka, and of its overlap with depression.
A total of 4024 randomly selected twins from a population-based register in Sri Lanka (Colombo district) completed home interviews including the Chalder Fatigue Questionnaire.
The prevalence of fatigue was similar to that in other countries, although prolonged fatigue may be less common. There was substantial comorbidity with a screen for lifetime depression. Non-shared environmental factors made the largest contributions, although genetic/family factors also contributed. The aetiology appeared consistent across the spectrum of severity.
The aetiology of fatigue is broadly similar in Sri Lanka and Western high-income countries. Abnormal experiences of fatigue appear to be the extreme form of more common fatigue, rather than representing independent entities with different genetic or environmental risk factors.