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The utility of questionnaire based self-report measures for non-clinical psychotic symptoms is unclear and there are few reliable data about the nature and prevalence of these phenomena in children. The study aimed to investigate psychosis-like symptoms (PLIKS) in children utilizing both self-report measures and semi-structured observer rated assessments.
The study was cross-sectional; the setting being an assessment clinic for members of the ALSPAC birth cohort in Bristol, UK. 6455 respondents were assessed over 21 months, mean age 12.9 years. The main outcome measure was: 12 self-report screening questions for psychotic symptoms followed by semi-structured observer rated assessments by trained psychology graduates. The assessment instrument utilised stem questions, glossary definitions, and rating rules adapted from DISC-IV and SCAN items.
The 6-month period prevalence for one or more PLIKS rated by self-report questions was 38.9 % (95% CI = 37.7-40.1). Prevalence using observer rated assessments was 13.7% (95% CI = 12.8-14.5). Positive Predictive Values for the screen questions versus observer rated scores were low, except for auditory hallucinations (PPV=70%; 95% CI = 67.1-74.2). The most frequent observer rated symptom was auditory hallucinations (7.3%); in 18.8% of these cases symptoms occurred weekly or more. The prevalence of DSM-IV ‘core’ schizophrenia symptoms was 3.62%. Rates were significantly higher in children with low socio-economic status.
With the exception of auditory hallucinations, self-rated questionnaires are likely to substantially over-estimate the frequency of PLIKS in 12-year-old children. However, more reliable observer rated assessments reveal that PLIKS occur in a significant proportion of children.
Results of adulthood mental health of those born late-preterm (34 + 0–36 + 6 weeks + days of gestation) are mixed and based on national registers. We examined if late-preterm birth was associated with a higher risk for common mental disorders in young adulthood when using a diagnostic interview, and if this risk decreased as gestational age increased.
A total of 800 young adults (mean = 25.3, s.d. = 0.62 years), born 1985–1986, participated in a follow-up of the Arvo Ylppö Longitudinal Study. Common mental disorders (mood, anxiety and substance use disorders) during the past 12 months were defined using the Composite International Diagnostic Interview (Munich version). Gestational age was extracted from hospital birth records and categorized into early-preterm (<34 + 0, n = 37), late-preterm (34 + 0–36 + 6, n = 106), term (37 + 0–41 + 6, n = 617) and post-term (⩾42 + 0, n = 40).
Those born late-preterm and at term were at a similar risk for any common mental disorder [odds ratio (OR) 1.11, 95% confidence interval (CI) 0.67–1.84], for mood (OR 1.11, 95% CI 0.54–2.25), anxiety (OR 1.00, 95% CI 0.40–2.50) and substance use (OR 1.31, 95% CI 0.74–2.32) disorders, and co-morbidity of these disorders (p = 0.38). While the mental disorder risk decreased significantly as gestational age increased, the trend was driven by a higher risk in those born early-preterm.
Using a cohort born during the advanced neonatal and early childhood care, we found that not all individuals born preterm are at risk for common mental disorders in young adulthood – those born late-preterm are not, while those born early-preterm are at a higher risk. Available resources for prevention and intervention should be targeted towards the preterm group born the earliest.
We report two cases of Star-Planet Interaction (SPI) in two systems with hot Jupiters: HD 189733 and HD 17156. We used HST-COS to study the FUV variability of HD 189733 after the planetary eclipse. With the support of MHD simulations, we evince that material is likely evaporating from the planet and accreting onto the parent star. This produces a hot spot on the stellar surface, co-moving with the planetary motion and responsible of the X-ray and FUV variability at peculiar planetary phases. In HD 17156, which hosts a hot Jupiter in an eccentric orbit, we observed an enhancement of the X-ray activity at the passage of its planet at the periastron. The origin can be due to magnetic reconnection between the planetary and stellar magnetic fields, or due to material tidally stripped from the planet and accreting onto the star.
Affective instability (AI) is poorly defined but considered clinically important. The aim of this study was to examine definitions and measures of AI employed in clinical populations.
This study was a systematic review using the PRISMA guidelines. MEDLINE, Embase, PsycINFO, PsycArticles and Web of Science databases were searched. Also five journals were hand searched. Primary empirical studies involving randomized controlled trials (RCTs), non-RCTs, controlled before and after, and observational investigations were included. Studies were selected, data extracted and quality appraised. A narrative synthesis was completed.
A total of 11 443 abstracts were screened and 37 studies selected for final analysis on the basis that they provided a definition and measure of AI. Numbers of definitions for each of the terms employed in included studies were: AI (n = 7), affective lability (n = 6), affective dysregulation (n = 1), emotional dysregulation (n = 4), emotion regulation (n = 2), emotional lability (n = 1), mood instability (n = 2), mood lability (n = 1) and mood swings (n = 1); however, these concepts showed considerable overlap in features. A total of 24 distinct measures were identified that could be categorized as primarily measuring one of four facets of AI (oscillation, intensity, ability to regulate and affect change triggered by environment) or as measuring general emotional regulation.
A clearer definition of AI is required. We propose AI be defined as ‘rapid oscillations of intense affect, with a difficulty in regulating these oscillations or their behavioural consequences’. No single measure comprehensively assesses AI and a combination of current measures is required for assessment. A new short measure of AI that is reliable and validated against external criteria is needed.
It is a long-standing question in exoplanet research if Hot Jupiters can influence the magnetic activity of their host stars. While cool stars usually spin down with age and become inactive, an input of angular momentum through tidal interaction, as seen for example in close binaries, can preserve high activity levels over time. This may also be the case for cool stars hosting a Hot Jupiter. However, selection effects from planet detection methods often dominate the activity levels seen in samples of exoplanet host stars, and planet-induced, systematically enhanced stellar activity has not been detected unambiguously so far. We have developed an approach to identify planet-induced stellar spin-up avoiding the selection biases from planet detection, by using visual proper motion binaries in which only one of the stars possesses a Hot Jupiter. This approach immediately rids one of the ambiguities of detection biases: with two co-eval stars, the second star acts as a negative control. We present results from our ongoing observational campaign at X-ray wavelengths and in the optical, and present several outstanding systems which display significant age/activity discrepancies presumably caused by their Hot Jupiters.
Stars in the very early stages of their formation are characterized by strong infrared excess and X-ray emission. We present the results of the survey of Orion A in both the infrared and X-rays obtained with the Spitzer and XMM/Newton observatories. We study the spectral-energy distribution class of the young stellar object (YSO) population using infrared colors from 2mass and Spitzer (IRAC and MIPS) and by means of X-ray fluxes, luminosities and plasma temperatures. We discuss clustering properties and spatial segregation among different infrared YSO classes to trace their formation history.
Previous studies have suggested that impaired fetal and childhood growth
are associated with an increased risk of schizophrenia, but the
association of pre-adult growth with non-clinical psychotic symptoms
(psychosis-like symptoms) in children is not known.
To explore the associations of body size at birth and age 7.5 years with
childhood psychosis-like symptoms.
Prospective cohort of children followed up from birth to age 12: the
Data on 6000 singleton infants born after 37 weeks of gestation. A one
standard deviation increase in birth weight was associated with an 18%
reduction in the risk of definite psychosis-like symptoms after adjusting
for age and gestation (Odds ratio (OR) = 0.82, 95% CI = 0.73–0.92,
P = 0.001). This association was partly confounded by
maternal anthropometry, smoking during pregnancy, socioeconomic status
and IQ. A similar association was seen for birth length and
psychosis-like symptoms, which disappeared after controlling for birth
weight. There was little evidence for an association of 7-year height or
adiposity with psychosis-like symptoms.
Measures of impaired fetal, but not childhood, growth are associated with
an increased risk of psychosis-like symptoms in 12-year-olds.
Non-clinical psychosis-like symptoms (PLIKS) occur in about 15% of the population. It is not clear whether adverse events during early development alter the risk of developing PLIKS. We aimed to examine whether maternal infection, diabetes or pre-eclampsia during pregnancy, gestational age, perinatal cardiopulmonary resuscitation or 5-min Apgar score were associated with development of psychotic symptoms during early adolescence.
A longitudinal study of 6356 12-year-old adolescents who completed a semi-structured interview for psychotic symptoms in the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort. Prenatal and perinatal data were obtained from obstetric records and maternal questionnaires completed during pregnancy.
The presence of definite psychotic symptoms was associated with maternal infection during pregnancy [adjusted odds ratio (OR) 1.44, 95% confidence interval (CI) 1.11–1.86, p=0.006], maternal diabetes (adjusted OR 3.43, 95% CI 1.14–10.36, p=0.029), need for resuscitation (adjusted OR 1.50, 95% CI 0.97–2.31, p=0.065) and 5-min Apgar score (adjusted OR per unit decrease 1.30, 95% CI 1.12–1.50, p<0.001). None of these associations were mediated by childhood IQ score. Most associations persisted, but were less strong, when including suspected symptoms as part of the outcome. There was no association between PLIKS and gestational age or pre-eclampsia.
Adverse events during early development may lead to an increased risk of developing PLIKS. Although the status of PLIKS in relation to clinical disorders such as schizophrenia is not clear, the similarity between these results and findings reported for schizophrenia indicates that future studies of PLIKS may help us to understand how psychotic experiences and clinical disorders develop throughout the life-course.
The combination of spatial and spectral resolution allow us to use Chandra in the study regions of massive star formation which had been inaccessible even from the ground until the last decade. IRAC and MIPS data from Spitzer can be combined with the X–ray data to provide insight into the presence of a disk and the activity of the star. The total package allows us to better understand the evolution of the clusters. We have an ongoing program to study several young star forming clusters including distant clusters between 1-3 kpc which support O stars, RCW 38, NGC 281 and RCW 108 and well as clusters within a kpc including IRAS 20050+2720 and NGC 1579, which is a small cluster centered on the Be star LkHα101 and is of uncertain distance although the X-ray data help us refine the current distance estimates. Given the space constraints we only discuss RCW 108 below.
Objectives: This study assesses the
implications and cost-effectiveness of extending the role of midwives to
include the routine (24-hour) examination of the healthy newborn usually
carried out by junior doctors.
We have photometrically identified eleven candidate brown dwarfs in 0.2 deg2 of the Orion OB1b association. This is consistent with a rising mass function down to ~0.06M⊙. Assuming the IMF of Kroupa (2002) this suggests a population of 40–200 brown dwarfs per deg2 (0.01M<0.075M⊙).
As part of our ongoing research into low–mass star formation in Orion, we have obtained deep photometric and spectroscopic observations of PMS objects in the σ Orionis cluster and near the other O stars in the belt of Orion. The photometry indicates the existence of objects with masses as low as 0.01 M⊙ (100 Mjup). Spectroscopic follow-up has confirmed the sub-stellar nature of the candidate object tested.
The Orion OB associations are one of the richest star forming regions in the local galaxy. Recently, we have made a concentrated effort to study the stars near belt of Orion within the Orion OB1a and OB1b associations. ROSAT observations totaling 100 Ksec of this region have been supplemented with ground based spectroscopy and photometry (Wolk 1996). These data demonstrated the clear existence of a 1-5 Myr old pre–main sequence of stars with common space motion and density of sources reaching a maximum at the location of σ Orionis. The confluence of this data lead us to conclude that the stars near σ Orionis form a young stellar cluster with a central density of at least 50 stars/pc3 (Walter et al. 1997, Walter et al. 1998). Similar clusters of older stars seem to exist near the other O stars in the belt of Orion.
Forty-seven children with non-organic failure to thrive (NOFT) were identified from a whole-population survey of children's growth and development. A significant proportion (N=17) of these 47 children were found to have oral-motor dysfunction (OMD) identified using a previously validated assessment tool. NOFT children with OMD and those with normal oral-motor function (N=30) were compared in order to ascertain whether there were any neurodevelopmental differences which might explain this finding. We hypothesized that children with OMD might have a subtle neurodevelopmental disorder. Few psychosocial variables discriminated the two groups. However, cognitive stimulation within the home and cognitive-growth fostering during mealtimes was much poorer for children with OMD. Some evidence has suggested that NOFT children with OMD may be ‘biologically’ more vulnerable from birth. We suggest that the continued use of the term ‘non-organic’ to describe failure to thrive in such children is questionable and requires redefining.
We report on the observation of optical quenching of persistent photoconductivity (PPC) in unintentionally doped n-type GaN films. The PPC is induced by subbandgap illumination between room temperature and 77K. The corresponding decay, which.is thermally activated, is substantially increased upon low energy illumination, e.g. illumination by wavelengths between 1O50nm and 700nm. We measure the saturation conductivity under simultaneous illumination with excitation and quenching light and find that some wavelengths can induce both excitation and quenching of photoconductivity. Additionally, we present a preliminary investigation of the spectral dependence of the quenching effect. A simulation indicates only a weak spectral dependence of the quenching cross-sections in the wavelength range from 470nm–1050nm.
Laser-assisted dry etching of lithium niobate, LiNbO3, as well as other electro-optic materials could be an industrially important process in the fabrication of optical waveguides. In this investigation, an excimer laser (ArF; 193nm) was used to conduct etching reactions using nitrogen trifluoride, NF3. Enhancement of etching was observed by comparing the etch rate for a gas assisted process with that of a purely photoablative process. Chemical analysis of the etched features via Auger electron spectroscopy and correlation of a simple rate equation with the experimental data revealed that lasersurface interactions are responsible for the laser-assisted etching process.
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