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There is a growing debate with regards to the appropriate methods of analysis of growth trajectories and their association with prospective dependent outcomes. Using the example of childhood growth and adult BP, we conducted an extensive simulation study to explore four two-stage and two joint modelling methods, and compared their bias and coverage in estimation of the (unconditional) association between birth length and later BP, and the association between growth rate and later BP (conditional on birth length). We show that the two-stage method of using multilevel models to estimate growth parameters and relating these to outcome gives unbiased estimates of the conditional associations between growth and outcome. Using simulations, we demonstrate that the simple methods resulted in bias in the presence of measurement error, as did the two-stage multilevel method when looking at the total (unconditional) association of birth length with outcome. The two joint modelling methods gave unbiased results, but using the re-inflated residuals led to undercoverage of the confidence intervals. We conclude that either joint modelling or the simpler two-stage multilevel approach can be used to estimate conditional associations between growth and later outcomes, but that only joint modelling is unbiased with nominal coverage for unconditional associations. [ABSTRACT FROM AUTHOR]

Background Cognitive theories of depression suggest that beliefs of low self-worth and the tendency to attribute negative events to causes that are global (widespread rather than specific) and stable (will persist rather than change in the future) are associated with the development of depressed mood. Such theories are supported by evidence from prospective studies and have guided the development of successful treatment and prevention strategies such as CBT. However, the relative importance of different psychological constructs within cognitive theories is unknown. This is important to refine cognitive theories and develop more efficient prevention strategies. Method We used prospective data from over 3500 young adults from the Avon Longitudinal Study for Parents and Children (ALSPAC) cohort in the UK to investigate the association between cognitive style, measured by short forms of the Dysfunctional Attitudes Scale (DAS) and Cognitive Styles Questionnaire-Short Form (CSQ-SF) at age 18, and future depressed mood at age 19. Structural equation modelling techniques were used to separate cognitive style constructs. Results Cognitive styles were associated with future depressed mood, independently of baseline mood, both as measured by the DAS-SF and the CSQ-SF. Of the different CSQ-SF constructs, only global attributions were associated with both baseline and future mood independently of other constructs. Limitations The study was subject to attrition and the follow-up was relatively short (10 months). Conclusion The findings suggest that the tendency to attribute negative events specifically to global causes could be particularly important for depression. Reducing global attributions is potentially important in the prevention and treatment of depression. [ABSTRACT FROM AUTHOR]

The technological appeal of multiferroics is the ability to control magnetism with electric field. For devices to be useful, such control must be achieved at room temperature. The only single-phase multiferroic material exhibiting unambiguous magnetoelectric coupling at room temperature is BiFeO3 (refs 4 and 5). Its weak ferromagnetism arises from the canting of the antiferromagnetically aligned spins by the Dzyaloshinskii-Moriya (DM) interaction. Prior theory considered the symmetry of the thermodynamic ground state and concluded that direct 180-degree switching of the DM vector by the ferroelectric polarization was forbidden. Instead, we examined the kinetics of the switching process, something not considered previously in theoretical work. Here we show a deterministic reversal of the DM vector and canted moment using an electric field at room temperature. First-principles calculations reveal that the switching kinetics favours a two-step switching process. In each step the DM vector and polarization are coupled and 180-degree deterministic switching of magnetization hence becomes possible, in agreement with experimental observation. We exploit this switching to demonstrate energy-efficient control of a spin-valve device at room temperature. The energy per unit area required is approximately an order of magnitude less than that needed for spin-transfer torque switching. Given that the DM interaction is fundamental to single-phase multiferroics and magnetoelectrics, our results suggest ways to engineer magnetoelectric switching and tailor technologically pertinent functionality for nanometre-scale, low-energy-consumption, non-volatile magnetoelectronics. [ABSTRACT FROM AUTHOR]

Conventional CMOS based logic and magnetic based data storage devices require the shuttling of electrons for data processing and storage. As these devices are scaled to increasingly smaller dimensions in the pursuit of speed and storage density, significant energy dissipation in the form of heat has become a center stage issue for the microelectronics industry. By taking advantage of the strong correlations between ferroic orders in multiferroics, specifically the coupling between ferroelectric and magnetic orders (magnetoelectricity), new device functionalities with ultra-low energy consumption can be envisioned. In this article, we review the advances and highlight challenges toward this goal with a particular focus on the room temperature magnetoelectric multiferroic, BiFeO3, exchange coupled to a ferromagnet. We summarize our understanding of the nature of exchange coupling and the mechanisms of the voltage control of ferromagnetism observed in these heterostructures. [ABSTRACT FROM AUTHOR]

Background Temperamental characteristics emerge early in life and can shape children's development, adjustment and behaviour. We aimed to investigate the association between early infant temperament and later childhood psychiatric disorder in a community sample. Methods This prospective, population-based study used data from the Avon Longitudinal Study of Parents and Children ( ALSPAC). In a sample of 7318 children, we investigated whether temperamental characteristics assessed at the ages of 6 months and 24 months are associated with an independent diagnosis of psychiatric disorder ascertained at age 7 years. Results After adjusting for confounders, temperamental characteristics assessed at 6 and 24 months of age were associated with psychiatric disorder at age 7 years. In particular, intensity of emotional reaction at age 6 months was associated with later disorder (adjusted odds ratio = 1.56; 95% confidence interval 1.19, 2.04; P = 0.002). These associations were stronger in girls and in those children with high levels of intensity at both 6 and 24 months of age. Conclusions Temperamental characteristics involving high levels of emotional intensity within the first year of life are longitudinally associated with psychiatric disorder in mid-childhood, suggesting that the roots of psychiatric disorder may, in some cases, lie very early in life. [ABSTRACT FROM AUTHOR]

There has been an expansion in the use of x-ray imaging during the last 20 years. Effective arrangements for justification of exposures as well as for optimisation of protection are crucial. The amount of effort put into the latter, the way in which it is organised and the groups carrying this out vary across the globe. A simple survey of organisational arrangements relating to performance testing of x-ray equipment, management of patient dose and other aspects of implementing optimisation has been undertaken. A total of 137 completed survey forms were received from medical physicists in 48 countries. Results for individual countries from which more responses were received, or for groups of neighbouring ones, are compared to portray variations. Some performance testing of x-ray equipment was mandated in most countries (more than 90%), with the tests being performed primarily by hospital or private medical physicists, although other groups are involved. Testing of equipment prior to clinical use was generally high for most regions, but the frequency was lower in Latin America. There was considerable variation in the frequency and regularity of subsequent testing. The prevalence of patient dose surveys was high in Europe, but lower in other continents. Organisational arrangements for testing performance of x-ray equipment, patient dose surveys and implementing optimisation of protection in medical exposures across the globe can be divided into five main groups. Hospital medical physicists take the lead in western Europe and Australia with the involvement of radiographers. Private medical physicists test equipment in Brazil, the USA and New Zealand, and have some responsibility for optimisation in Brazil. University personnel have significant involvement, together with medical physicists in eastern Europe, but the extent of the coverage is uncertain. Government personnel and service engineers carry out equipment testing in many countries of Africa and Asia, while radiographers have a significant role in Thailand and other countries where the number of medical physicists is limited. In order for dose surveys to have an impact, action must be taken upon the findings, but there must be an effective link between surveyors and radiology facility staff to ensure that this is done. [ABSTRACT FROM AUTHOR]

BackgroundPrevious studies suggest a link between parental separation or divorce and risk of depression in adolescence. There are, however, few studies that have prospectively examined the effects of timing of biological father absence on risk for depressive symptoms in adolescence while controlling for a range of confounding factors.MethodWe examine the association between father absence occurring in early (the first 5 years) and middle childhood (5–10 years) and adolescent depressive symptoms in a sample comprising 5631 children from the UK-based Avon Longitudinal Study of Parents and Children (ALSPAC). Self-reported depressive symptoms at 14 years were assessed using the Short Mood and Feelings Questionnaire (SMFQ). Father absence was assessed from maternal questionnaires completed at regular intervals from the birth of the study child up to 10 years.ResultsThere was evidence for an association between father absence in early childhood and increased odds of depressive symptoms at 14 years. This association was stronger in girls than in boys and remained after adjusting for a range of socio-economic, maternal and familial confounders assessed prior to the father's departure. Conversely, there was no evidence for an association between father absence in middle childhood and depressive symptoms at 14 years.ConclusionsFather absence in early childhood increases risk for adolescent depressive symptoms, particularly in girls. Future research should be aimed at identifying possible biological and psychosocial mechanisms linking father absence to depressive symptomatology to enable the development of family-based early prevention and intervention programmes targeting young children at risk. [ABSTRACT FROM PUBLISHER]

The aim of the study was to investigate the influence of alcohol exposure during pregnancy on a mother's responsiveness towards her infant after birth. Using longitudinal data from a subsample of 687 mother-infant dyads from a UK cohort study (Avon Longitudinal Study of Parents and Children), we investigated the influence of alcohol use during mid- and late pregnancy on observed mother-infant interactions after birth. We found that women who drank one or more glasses of alcohol a week during their mid-trimester of pregnancy were 19 % (95 % CI, 1 to 40 %; p = 0.033) more likely to show non-responsive behaviour towards their infant 12 months after birth. In contrast, we found that alcohol use during late pregnancy was not associated with later maternal responsiveness. This study adds to the growing evidence for the importance of factors during pregnancy on later maternal responsiveness. Further research is needed to replicate these findings and to examine potential mechanisms linking maternal responsiveness to alcohol use during pregnancy. [ABSTRACT FROM AUTHOR]

Background. It is unclear whether pubertal status or timing of puberty explains the increase in depressive symptoms in girls during adolescence. Method. This is a longitudinal study based on 2506 girls from the Avon Longitudinal Study of Parents and Children (ALSPAC). Self-reported depressive symptoms at 10.5, 13 and 14 years were assessed using the Short Mood and Feelings Questionnaire (SMFQ). Pubertal status (Tanner breast and pubic hair stage) and timing of menarche were derived from questionnaires administered from age 8 to 14 years. We used multivariable regression models to examine the relative contributions of pubertal status and timing in accounting for increases in level of depressive symptoms at 14 years. Results. With increasing age, the association between breast development and depressive symptoms strengthened. Pubertal status (breast stage), rather than timing of menarche, was independently associated with depressive symptoms at 14 years. There was strong evidence for a linear relationship between breast stage and depressive symptoms at 14 years [increase in 0.17 S.D. (range 0.10-0.24) of depressive symptoms for advancement of each breast stage]. Conclusions. Depressive symptoms in mid-adolescence were more strongly influenced by breast stage than timing of menarche. This could imply that the female rise in depression during adolescence is due to increasing estrogen levels, and might explain why the gender difference in rates of depression emerges at this stage. Future research should be aimed at identifying the mechanism of action of pubertal change, including direct effects of pubertal hormones and indirect effects mediated by psychosocial factors. [ABSTRACT FROM AUTHOR]

Abstract: Aims: The perinatal period is a time of high risk of relapse for women with a history of bipolar affective disorder (BPAD). We describe the pregnancy management of women with BPAD and identify risk factors for postpartum relapse. Methods: The case records of 78 women with BPAD referred to perinatal mental health services before conception, during pregnancy or the postpartum period, between 1998 and 2009 in Birmingham UK, were screened. In women who were managed during pregnancy, those who relapsed in the postpartum were compared with those who remained well. Results: Forty-seven percent of women with BPAD referred in pregnancy suffered postpartum relapse. Women who were unwell at referral, younger, with unplanned pregnancy, previous perinatal episodes or a family history of BPAD were more likely to suffer postpartum illness. Conclusion: Identifying risk factors for postpartum relapse enables us to individualise the estimation of a woman''s risk and modify care plans accordingly. Duration of wellness prior to pregnancy is not associated with a lower risk of postpartum illness and so it is imperative that all women with BPAD receive referral in pregnancy. [Copyright &y& Elsevier]

Background Both maternal and paternal depression during the perinatal period are associated with adverse effects on child outcomes. Attention has started to focus on the mechanisms mediating these relationships. Marital conflict may play a role in this context. Methods In a large cohort study, the Avon Longitudinal Study of Parents and Children ( n= 14 541 pregnancies), we aimed to (i) investigate the relative influences of parental postnatal depression and marital conflict on child outcomes and to attempt to determine the pathway(s) of risk; (ii) investigate the impact of two types of antenatal stress (parental depression and marital conflict) on child outcomes; and (iii) determine the relative contributions of antenatal and postnatal risk. Parents completed the Edinburgh Postnatal Depression Scale and a marital conflict scale during the second trimester and at 8 months postnatally. Child outcomes were assessed at 42 months using the Rutter revised pre-school scales. Results Marital conflict partially mediated the relationship between postnatal depression in both mothers and fathers and child outcomes, and acted as an independent risk for adverse outcomes. Parental depression (maternal and paternal) and marital conflict in the antenatal period were both associated with adverse effects which persisted even when postnatal stresses were taken into account. Conclusions These findings, if replicated, suggest that screening and intervention programmes targeted at parental depression and marital problems should be considered antenatally, as well as postnatally. [ABSTRACT FROM AUTHOR]

Abstract: Background: An infant''s early environment has an important influence on their development. For example, the sensitivity and warmth of a mother''s responses towards her infant is associated with the infant''s later socio-emotional development. However, it is less clear whether maternal responses are associated with the infant''s later cognitive development. Method: We used data from a large UK cohort study to investigate the association between non-verbal maternal responses and later infant development and IQ. Maternal responses were rated at 12 months during an observed mother–infant interaction. Infant development was assessed using the Griffiths scales at 18 months and IQ at 4 years was assessed using the Wechsler Preschool and Primary Scale of Intelligence (WPPSI). Data on the infant''s developmental level at 6 months (prior to the maternal response ratings) was also available. The complete case sample comprised 732 mother–infant pairs. Results: There was evidence for an association between positive maternal responses and infant development at 18 months. After adjusting for infant developmental level at 6 months and other confounders, we found a difference of 0.25 standard deviations (coef 2.0, 95% CI (0.8–3.2), p =0.002) on the Griffiths scales between infant''s whose mothers showed positive compared to neutral non-verbal responses at 12 months. However, an association between positive maternal responses and IQ at 4 years diminished following adjustment for maternal educational attainment. Conclusion: The results provide evidence that positive maternal responses are associated with improved development in infants at 18 months. However, the association between maternal response and IQ at 4 years may be explained by higher educational attainment in mothers who show positive responses. Future studies are needed to explore the influence of maternal responses on different aspects of infant development as well as the role of maternal factors such as education. [Copyright &y& Elsevier]

A reversal of magnetization requiring only the application of an electric field can lead to low-power spintronic devices by eliminating conventional magnetic switching methods. Here we show a nonvolatile, room temperature magnetization reversal determined by an electric field in a ferromagnet-multiferroic system. The effect is reversible and mediated by an interfacial magnetic coupling dictated by the multiferroic. Such electric-field control of a magnetoelectric device demonstrates an avenue for next-generation, low-energy consumption spintronics. [ABSTRACT FROM AUTHOR]

Aim: Few studies have looked at the prevalence of daytime incontinence in a longitudinal cohort of children. This study set out to determine the prevalence of daytime incontinence and relationships between daytime incontinence and bedwetting, faecal incontinence and urgency in a large cohort of British children. Methods: Parents of children taking part in the Avon Longitudinal Study of Parents and Children (ALSPAC) were asked questions concerning the child’s daytime wetting, bedwetting and faecal incontinence at different time points, 4.5, 5.5, 6.5, 7.5 and 9.5 years. The difference between the sexes for these different conditions was compared. Results and limitations: Data were available for 10 819 of the 13 973 children who entered the study. The prevalence of any daytime incontinence declined from 15.5% at 4.5 years to 4.9% at 9.5 years, and was mainly described as infrequent. Daytime incontinence was more common in girls than boys and frequent (DSM-IV) incontinence was more commonly related to urgency, bedwetting and faecal incontinence than infrequent incontinence. Conclusions: Daytime incontinence is relatively common among children of primary school age and frequent incontinence more commonly coexists with other conditions, such as bedwetting and urgency. This study suggests the need for treatment to focus on children with frequent incontinence. [ABSTRACT FROM AUTHOR]

We examine the prevalence of hypomania on day 3 postpartum using two self-report mania scales: The Highs Scale and Altman Mania Rating Scale (AMRS). 279 women were recruited from postnatal wards and completed the questionnaires on day 3 postpartum. The scales show good correlation, however, 11% of women meet the suggested threshold for caseness on the Highs Scale and 44% on the AMRS. Hypomanic symptoms are commonly experienced in the early postpartum. Although there is some evidence that the Highs Scale might be conservative, the AMRS likely overestimates hypomania in the postpartum. The definition of what constitutes ‘a case’ of postnatal hypomania requires further validation against clinical interview and ability to predict variables of clinical importance. Mania scales developed in bipolar disorder populations must be specifically validated for postpartum use. [ABSTRACT FROM AUTHOR]

We report the measurement of thermal conductance of silicon nanowires at low temperature. It is demonstrated that the roughness at the nanometer scale plays a crucial role for the phonon transport in low-dimensional samples. To this end, using e-beam lithography, nanowires of size 200 nm by 100 nm and 10 μm long have been nanofabricated. Their thermal properties have been measured using the 3 ω method between 0.3 and 6 K. The change in the temperature behavior of the thermal conductance (quadratic temperature dependence of K(T)) is a signature of an intermediate regime lying between the classical Casimir regime and the quantum regime. The Casimir-Ziman model is used to show that this specific behavior originates in mesoscopic samples where the dominant phonon wavelength becomes commensurate to the characteristic length of the roughness of the nanowire surfaces. [ABSTRACT FROM AUTHOR]

Objective Postpartum depression in mothers is associated with developmental problems in their children. Many women who are depressed following childbirth are also depressed during pregnancy. The aim of this study was to examine the associations between maternal depressive symptoms during pregnancy and child development at 18 months of age. Design A prospective cohort study, Avon Longitudinal Study of Parents and Children. Setting The former county of Avon, southwest England. Population All pregnant women in the defined area with delivery dates between April 1991 and December 1992, 9244 women and their children. Methods Data were collected antenatally, at 18 and 32 weeks of gestation and at 8 weeks and 8 months postnatally, through postal questionnaires, including a self-report measure of depression (Edinburgh Postnatal Depression Scale [EPDS]). By the time their child was 18 months old, women completed five further questionnaires about their children’s health and development. Main outcome measure Child development at 18 months using a modified Denver Developmental Screening Test (modified DDST). Results Applying the standard 12/13 cutoff, 1565 (14%) women were depressed antenatally but not at either time-points postnatally. Employing the modified DDST, 893 (9%) children were developmentally delayed at 18 months of age. Persistent depression (EPDS ≥ 10 at both time-points) is associated with developmental delay (adjusted OR 1.34, 95% CI 1.11–1.62). Applying the 12/13 and 14/15 cutoffs gave similar results. After further adjustment for postnatal depression, the effect sizes were slightly attenuated. Conclusions These findings highlight the importance of depression in pregnancy. Some effects on child development attributed to postpartum depression are caused in part by depressive symptoms during pregnancy. [ABSTRACT FROM AUTHOR]

Background A recent study suggested a link between folate metabolism and atopy, based on a positive association between a common polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene and allergic sensitization in Danish adults. Objective We investigated the associations between MTHFR C677T and allergy or atopy in a large, population-based birth cohort of children and their mothers, the Avon Longitudinal Study of Parents and Children (ALSPAC). We also looked for evidence of a pre-natal effect of maternal folate metabolism on subsequent atopic disease in the offspring. Methods Mothers were recruited in pregnancy and the children followed from birth. Atopy in the child was assessed at 7–8 years of age by skin prick tests to common allergens. Asthma was defined as a physician diagnosis and current symptoms at 71/2 years of age. Asthma and allergy status of the mothers were obtained from self-completion questionnaires. Results Data on MTHFR C677T genotype and allergy were available for 5364 children and on allergy and/or asthma for 7356 mothers. In children, the prevalence of atopy was 20.0% and asthma 10.0% whereas in mothers, the prevalence of self-reported allergy was 42.7% and asthma 11.5%. Atopy in the child was associated with male gender ( P<0.001), less tobacco smoke exposure and higher maternal education. MTHFR C677T genotype was not associated with social factors or dietary folate intake. We found no evidence of associations between the MTHFR C677T variant allele and atopy, allergy or asthma in mothers or children. There was no evidence to support an effect of maternal MTHFR C677T genotype on atopy in the offspring. Conclusion The results of this study do not support the hypothesis that impaired folate metabolism is associated with allergy in adults or children in this population. [ABSTRACT FROM AUTHOR]

Objective To examine the nature of the earliest reported symptoms in women who develop a bipolar affective puerperal psychosis (PP). Design A retrospective interview study. Setting Women were recruited for clinical and molecular genetic studies of PP from a national PP network, articles in the national press and referrals from UK specialist perinatal psychiatry services. Sample One hundred and twenty-seven women met the criteria for an episode of strictly defined bipolar affective PP developing within 4 weeks of childbirth. Methods Participants were interviewed using the Schedule for clinical assessment in neuropsychiatry and hospital records were reviewed. Lifetime and puerperal episode diagnoses were made according to Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) based on all the available information. During interview, participants were asked to describe the earliest symptoms they believed to be related to their illness onset. The day of onset for each symptom was recorded. Main outcome measures We present subjectively experienced emotional and behavioural changes occurring within 3 days of childbirth, reported by four or more women. Results Seventy-three percent of women recalled experiencing an onset of symptoms by day 3. The most commonly recalled symptoms were feeling excited, elated or high (52%), not needing to sleep or not able to sleep (48%), feeling active or energetic (37%) and talking more or feeling very chatty (31%). Conclusions Hypomanic symptoms are particularly characteristic of the early postpartum in women who develop PP. These types of symptoms should be carefully monitored in individuals at high risk of PP episodes. [ABSTRACT FROM AUTHOR]

Background Although some empirical investigations have explored the impact of nocturnal enuresis for sufferers, little is known about how children in general understand nocturnal enuresis. This study employed a large cohort of children at 9 years, asking directly about the perceived difficulty of bed-wetting in relation to an extensive range of life events. Method The sample comprised 8209 children, 4012 (48.9%) male and 4197 (51.1%) female who, as part of the Avon Longitudinal Study of Parents and Children survey, completed a booklet called ‘My World’ which included a section of 21 items concerned with childhood difficulties. Results Bed-wetting was highly endorsed as a difficulty for children, and factor analysis revealed it to be construed as a social problem. Girls were more likely to consider events of a social and emotional nature to be difficult, whereas boys rated antisocial events as more problematic. Boys and those who suffer from nocturnal enuresis were significantly more likely to view bed-wetting as more difficult for children. Conclusion Bed-wetting, which is construed as a social issue, tends to be rated as a major difficulty for children, increasingly so for boys and those who suffer from nocturnal enuresis. [ABSTRACT FROM AUTHOR]

Aim: To describe the clinical presentation, procedure and outcome in patients treated with computed tomography (CT)-guided sacroplasty as a treatment for sacral insufficiency fractures. Materials and Methods: Three patients (mean age 80 years, range 75–87 years) were treated with CT-guided sacroplasty. The mean pre-procedure visual analogue score (VAS) for pain was 8 (range 7–9) with a mean symptom duration of 8 months (range 2.5–18). The procedure was performed under CT guidance with needles being placed along the fracture lines from a posterior approach. Polymethylmethacrylate (PMMA) cement was introduced in 0.2ml aliquots after cement temperature reduction. Cement injection was monitored by four-secton block axial acquisition to assess potential cement migration. Results: All three procedures were performed without significant complication. One patient developed a tiny asymptomatic cement leak into the S1 foramen. The mean volume of cement injected into a unilateral sacral fracture was 4ml. All patients tolerated the procedure well under intravenous sedation. The mean VAS score post-procedure was 2. Continued symptomatic relief was seen at 6 weeks and 3 months. Conclusion: CT-guided sacroplasty represents an alternative treatment for sacral insufficiency fractures that are resistant to conservative treatment. The symptomatic relief the procedure produces seems to be excellent both in this small series and in described cases in the literature. [Copyright &y& Elsevier]

Objective: The study aimed to determine the cognitive effect of the Val108/158Met polymorphism in the catechol-O-methyltransferase (COMT) gene in children before and during puberty. This polymorphism affects cognitive function in healthy adults and may contribute to risk for schizophrenia.Method: COMT genotype was determined for 8,707 children from the Avon Longitudinal Study of Parents and Children (ALSPAC), a geographically defined general population cohort of children born between April 1, 1991, and Dec. 31, 1992, in the southwest of England. Fourteen measures of cognitive function--including working memory, verbal and motor inhibition, attentional control, and IQ--were assessed at ages 8 and 10 years. Any pubertal development at age 9 years was reported by parents. Effects of COMT genotype on cognition and interactions with gender and puberty were assessed using general linear models.Results: In boys, genotype significantly affected executive function and explained up to 10 points normal variation in verbal IQ. The effects on IQ were significantly greater in pubertal than in prepubertal boys. In girls, there were no significant effects of genotype on cognition.Conclusions: This common polymorphism may be one of the genes of small effect that contribute to normal variation in IQ. The gender-specific nature of the effect and its possible interaction with puberty may be relevant to both normal cognitive and brain development and to abnormal development in disorders such as schizophrenia. [ABSTRACT FROM AUTHOR]

Auditory signals have been shown to exert a marked influence on visual perception in a wide range of tasks. However, the mechanisms of these interactions are, at present, poorly understood. Here we present a series of experiments where a temporal cue within the auditory domain can significantly affect the localisation of a moving visual target. To investigate the mechanism of this interaction, we first modulated the spatial positional uncertainty of the visual target by varying its size. When visual positional uncertainty was low (small target size), auditory signals had little or no influence on perceived visual location. However, with increasing visual uncertainty (larger target sizes), auditory signals exerted a significantly greater influence on perceived visual location. We then altered the temporal profile of the auditory signal by modulating the spread of its Gaussian temporal envelope. Introducing this temporal uncertainty to the auditory signal greatly reduced its effect on visual localisation judgements. These findings support the view that the relative uncertainty in individual sensory domains governs the perceptual outcome of multisensory integration. [Copyright &y& Elsevier]

OBJECTIVE: There is an established link between exposure to mercury and impaired childhood cognitive development and early motor skills. Thimerosal (also known as thiomersal), a preservative used in a number of children's vaccines, contains ethylmercury (an organic compound of mercury), and there has been concern that this exposure to mercury may be of some detriment to young children. The aim of this research was to test in a large United Kingdom population-based cohort whether there is any evidence to justify such concerns. METHODS: We used population data from a longitudinal study on childhood health and development. The study has been monitoring >14,000 children who are from the geographic area formerly known as Avon, United Kingdom, and were delivered in 1991-1992. The age at which doses of thimerosal-containing vaccines were administered was recorded, and measures of mercury exposure by 3, 4, and 6 months of age were calculated and compared with a number of measures of childhood cognitive and behavioral development covering the period from 6 to 91 months of age. RESULTS: Contrary to expectation, it was common for the unadjusted results to suggest a beneficial effect of thimerosal exposure. For example, exposure at 3 months was inversely associated with hyperactivity and conduct problems at 47 months; motor development at 6 months and at 30 months; difficulties with sounds at 81 months; and speech therapy, special needs, and 'statementing' at 91 months. After adjustment for birth weight, gestation, gender, maternal education, parity, housing tenure, maternal smoking, breastfeeding, and ethnic origins, we found 1 result of 69 to be in the direction hypothesized-poor prosocial behavior at 47 months was associated with exposure by 3 months of age (odds ratio: 1.12; 95% confidence interval: 1.01-1.23) compared with 8 results that still supported a beneficial effect. CONCLUSIONS: We could find no convincing evidence that early exposure to thimerosal had any deleterious effect on neurologic or psychological outcome. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated that schizophrenia patients score highly on self-reported measures of schizotypy such as the Kings Schizotypy Questionnaire (KSQ), but relatively little is known about the specificity of these self-reported features to schizophrenia. We aimed to explore the specificity of schizotypal features to schizophrenia by measuring their prevalence in subjects with bipolar disorder. The Kings Schizotypy Questionnaire (KSQ) was administered to participants (n=92) in a sibling–pair genetic linkage study of bipolar disorder. Scores were compared with those of participants in a similarly designed, concurrent family study of schizophrenia (n=135) and psychiatrically well controls (n=263). The bipolar group had significantly more schizotypal features than controls but significantly less than schizophrenia patients. Whether a bipolar subject had experienced positive psychosis had no effect on his/her schizotypy score. We conclude that elevated self-reported schizotypy as measured by the KSQ is not specific to schizophrenia, and may be associated with functional psychosis in general. [Copyright &y& Elsevier]

The weeks following childbirth are a period of high risk in bipolar women with manic or mixed affective episodes following 20-30% of deliveries. Although the vast majority of episodes have their onset within 2 weeks of delivery it is commonly believed that there is a 'latent' or symptom-free period in the first few days after delivery. We examine the day of onset of clinically significant symptoms in 101 bipolar women who have experienced an episode of puerperal (postpartum) psychosis. We find no evidence of a latent period. Over 50% of symptom onsets occur on days 1-3, with over 22% occurring on the first postpartum day. [ABSTRACT FROM AUTHOR]

The weeks following childbirth are a period of high risk in bipolar women with manic or mixed affective episodes following 20–30% of deliveries. Although the vast majority of episodes have their onset within 2 weeks of delivery it is commonly believed that there is a “latent” or symptom-free period in the first few days after delivery. We examine the day of onset of clinically significant symptoms in 101 bipolar women who have experienced an episode of puerperal (postpartum) psychosis. We find no evidence of a latent period. Over 50% of symptom onsets occur on days 1–3, with over 22% occurring on the first postpartum day. [ABSTRACT FROM AUTHOR]

The article traces the controversy surrounding the statues created by Jacob Epstein and placed at the British Medical Association (BMA) building. In 1908, architect Charles Holden commissioned Epstein to decorate the BMA buildings. Epstein created 18 larger than life-size statues of man and woman from birth to old age. A vendetta was initiated against the statues because of their depiction of nudity. In 1935, upon acquisition of the BMA building, Southern Rhodesia announced the removal of the statues.

Background: Long chain polyunsaturated fatty acid (PUFA) levels have been implicated in the pathology of psychotic disorders. We investigated the relationship between childhood PUFA levels and later psychotic experiences (PE's) in a large birth cohort.Methods: Plasma levels of Ω-3 and Ω-6 fatty acids (FA's) were assayed at ages 7 and 16 years. PE's were assessed at ages 12 and 18 years using a semi-structured interview. Primary outcome was any PE's at 18 years; sensitivity analyses examined incident PE's between ages 12 and 18 years, persistent PE's (at 12 and 18) and psychotic disorder at 18 years. Genetic instruments for Ω-3 and Ω-6 were derived and used in a multivariable Mendelian Randomization analysis.Results: Higher levels of Ω-6 FA's AA, OA and AdA at age 7 years were weakly associated with a reduced risk for PE's at 18 years, however, effect sizes were small and attenuated after adjusting for confounders (strongest evidence for OA; adjusted OR, 0.842; 95% CI, 0.711, 0.998; p, 0.048). Total Ω-6 levels at age 16 years were associated with an increased odds of psychotic disorder at age 18 years. However, there was no association between Ω-6/Ω-3 ratio and psychosis outcomes, nor with genetic instruments of total Ω-3 or Ω-6 levels.Conclusions: There is no strong evidence that total plasma Ω-3 FA levels or Ω-6/Ω-3 ratios in childhood and mid-adolescence are associated with increased risk for PE's or psychotic disorder, but very marginal evidence that alterations in the Ω-6 pathway at developmental time points might influence risk2. [ABSTRACT FROM AUTHOR]

We apply hybrid density functional theory calculations to identify the formation energies and thermodynamic charge transition levels of native point defects, common impurities, and shallow dopants in BAs. We find that AsB antisites, boron-related defects such as VB, BAs, and Bi-VB complexes, and antisite pairs are the dominant intrinsic defects. Native BAs is expected to exhibit p-type conduction due to the acceptor-type characteristics of VB and BAs. Among the common impurities we explored, we found that C substitutional defects and H interstitials have relatively low formation energies and are likely to contribute free holes. Interstitial hydrogen is surprisingly also found to be stable in the neutral charge state. BeB, SiAs, and GeAs are predicted to be excellent shallow acceptors with low ionization energy (<0.03 eV) and negligible compensation by other point defects considered here. On the other hand, donors such as SeAs, TeAs SiB, and GeB have a relatively large ionization energy (∼0.15 eV) and are likely to be passivated by native defects such as BAs and VB, as well as CAs, Hi, and HB. The hole and electron doping asymmetry originates from the heavy effective mass of the conduction band due to its boron orbital character, as well as from boron-related intrinsic defects that compensate donors. [ABSTRACT FROM AUTHOR]

Background: Sleep disturbances are important symptoms to monitor in people with bipolar disorder (BD) but the precise longitudinal relationships between sleep and mood remain unclear. We aimed to examine associations between stable and dynamic aspects of sleep and mood in people with BD, and assess individual differences in the strength of these associations. Methods: Participants (N = 649) with BD-I (N = 400) and BD-II (N = 249) provided weekly self-reports of insomnia, depression and (hypo)mania symptoms using the True Colours online monitoring tool for 21 months. Dynamic structural equation models were used to examine the interplay between weekly reports of insomnia and mood. The effects of clinical and demographic characteristics on associations were also assessed. Results: Increased variability in insomnia symptoms was associated with increased mood variability. In the sample as a whole, we found strong evidence of bidirectional relationships between insomnia and depressive symptoms but only weak support for bidirectional relationships between insomnia and (hypo)manic symptoms. We found substantial variability between participants in the strength of prospective associations between insomnia and mood, which depended on age, gender, bipolar subtype, and a history of rapid cycling. Conclusions: Our results highlight the importance of monitoring sleep in people with BD. However, researchers and clinicians investigating the association between sleep and mood should consider subgroup differences in this relationship. Advances in digital technology mean that intensive longitudinal data on sleep and mood are becoming increasingly available. Novel methods to analyse these data present an exciting opportunity for furthering our understanding of BD. [ABSTRACT FROM AUTHOR]

Abstract: Background: Exclusion from school is increasingly recognized as pertinent to child health. National educational data reveal that boys, children who are looked‐after, living in poverty, have special educational needs, or from certain ethnic minorities, are disproportionately excluded from school. As population‐based data on the wider characteristics of excluded children are scarce, we aimed to describe predictors of school exclusion in the Avon Longitudinal Study of Parents and Children. Method: Avon Longitudinal Study of Parents and Children, a prospective U.K. population‐based birth cohort study, collected parent reports of permanent school exclusions by 8 years and parent and self‐reports of permanent and fixed‐term exclusions in the preceding 12 months at 16 years. Potential risk factors were examined for associations with exclusion using logistic regression, with a focus on child mental health and neurodevelopment. Results: Analyses were based on all available data on 53/8,245 (0.6%) pupils excluded from school by 8 years and 390/4,482 (8.7%) at 16 years. Key factors associated with exclusion at both time points included male gender, lower socio‐economic status, maternal psychopathology, mental health and behavioural difficulties, psychiatric disorder, social communication difficulties, language difficulties, antisocial activities, bullying/being bulled, lower parental engagement with education, low school engagement, poor relationship with teacher, low educational attainment, and special educational needs (all p < .05). Conclusion: Exclusion from school was associated with child, family and school‐related factors identifiable at, or prior to, primary school age. Child health professionals have an important role in the holistic, multidisciplinary assessment of children who are at risk of exclusion from school. Mental health and neurodevelopmental difficulties should be recognized and supported, to improve the health and educational outcomes among this vulnerable group. [ABSTRACT FROM AUTHOR]

Complex oxides such as tin-doped indium oxide (ITO) are widely utilized as transparent conductors in a variety of functional devices. Typically, they are fabricated by sputtering, which often requires additional annealing to achieve high transparency and conductivity. Using pulsed laser deposition (PLD), both high transparency and high conductivity have been achieved without annealing, using instead selected gas species and pressures. However, the relative roles of Stranski-Krastanov-like and vapor-liquid-solid (VLS) growth modes during morphological transitions remain controversial. Here, we report on PLD of ITO in an inert-gas environment, identifying the role of plasma-plume expansion in the selection of VLS vs vapor-solid (VS) growth. For the lowest N2 pressure, indium-tin droplet formation, followed by self-catalyzed VLS growth, is observed. With increasing N2 pressure, a transition from VLS to VS growth is apparent. It is hypothesized that oxygen scattering at the lowest N2 pressure induces a metal-rich plume, which leads to metal droplet formation, followed by VLS growth. As the N2 pressure is increased, the plasma-plume and its metal-rich core are compressed, resulting in a transition to VS growth. This tunable compression of the plasma-plume offers a route to the morphological design of a wide range of functional complex oxide devices with tunable optical and electronic performance. [ABSTRACT FROM AUTHOR]

Objectives: To examine the association between advancing pubertal status and the emergence of depressive symptoms in boys and girls from a UK cohort. Methods: Self-reported depressive symptoms were assessed using the Short Mood and Feelings Questionnaire at three time-points (10.5, 13 and 14 years). We derived trait measures of depressive symptom level at each time-point using confirmatory factor analysis and compared the 3 depressive symptom factors with pubertal status (using regular self-reported Tanner assessments from 8-14 years) separately in boys (n=2902) and girls (n=2886). Main effects were estimated, adjusted for time lag between assessment of pubertal status and depressive symptoms, and then further adjusted for confounders (social class, maternal education, parental separation, financial problems, housing tenure). Results: For girls at age 10.5 years, there was little evidence of a relationship between pubertal status and depressive symptoms, with an increase in symptoms of 0.025 SD''s for each additional pubertal stage (indicated by Tanner stages 1 through 5) for breast development and 0.023 SD''s for each additional stage for pubic-hair development. With increasing age, the association between pubertal stage and depressive symptoms in girls strengthened. At age 14 years, advancement of each pubertal stage represented an increase in 0.13 SD''s of depressive symptoms for breast development and 0.10 SD''s for pubic hair development. For boys, there was no clear relationship between pubertal development and depressive symptoms at any time-point. Conclusions: More advanced pubertal status was associated with an increased level of depressive symptoms in girls in early/mid adolescence but not boys. [Copyright &y& Elsevier]

A correction to the article "The Association Between Mother and Child MTHFR C677T Polymorphisms, Dietary Folate Intake and Childhood Atopy in a Population-Based, Longitudinal Birth Cohort," by R. Granell, J. Heron, S. Lewis, G. Davey Smith, J.A.C. Sterne and J. Henderson is presented.

OBJECTIVE: The objective of this study was to examine differences in intellectual capacities between children with and without soiling, daytime wetting, and bed-wetting. METHODS: This study was based on a population of >6000 children (age range: 7 years 6 months to 9 years 3 months; median: 7 years 6 months) from the United Kingdom-based Avon Longitudinal Study of Parents and Children. Data on wetting and soiling were obtained from a questionnaire completed by parents. The Wechsler Intelligence Scale for Children-Third Edition was administered at a research clinic. RESULTS: Bed-wetting was associated with lower Wechsler Intelligence Scale for Children-Third Edition IQ scores compared with control subjects, particularly performance IQ. This difference remained after exclusion of children with an IQ of <70 and adjustment for gender, stressful life events, and sociodemographic background. There were fewer differences in IQ scores between children with and without soiling or daytime wetting. Co-occurring wetting and soiling were associated with lower IQ scores than isolated soiling, daytime wetting, or bed-wetting, but this was mostly attributable to an overrepresentation of children with an IQ of <70 in the co-occurrence group. CONCLUSIONS: It is hypothesized that the differences in intellectual capacities between children with and without bed-wetting are associated with maturational deficits of the central nervous system. There was less evidence for differences in intellectual capacities between children with and without soiling and daytime wetting. The central nervous system is involved to a lesser extent in soiling and daytime wetting, because peripheral influences from the bladder and gut play a greater role. [ABSTRACT FROM AUTHOR]

OBJECTIVES: High levels of alcohol use during pregnancy can lead to adverse physical and neurodevelopmental outcomes in children. It remains uncertain whether there is a safe level of drinking during pregnancy. In this study we investigate whether very low levels of alcohol consumption (<1 drink per week) are independently associated with childhood mental health problems (assessed at 3 time points between ages 4 and 8 years) and whether these effects are moderated by gender. We expected that only higher levels of alcohol consumption would be associated with later mental health problems and that any associations might be more readily detectable in boys. METHODS: This prospective, population-based study used data from the Avon Longitudinal Study of Parents and Children. We investigated the relationship between self-reports of the amount and frequency of alcohol use in the first trimester and the presence of clinically significant mental health (behavioral and emotional) problems at 47 and 81 months (parental report: n = 9086 and 8046, respectively) and at 93 to 108 months (teacher report: n = 5648). RESULTS: After controlling for a range of prenatal and postnatal factors, the consumption of <1 drink per week during the first trimester was independently associated with clinically significant mental health problems in girls at 47 months. This gender-specific association persisted at 81 months and was confirmed by later teacher ratings. CONCLUSIONS: Very low levels of alcohol consumption during early pregnancy may have a negative and persistent effect on mental health outcomes. Given the lack of a clear dose-response relationship and unexpected gender effects, these findings should be considered preliminary and need additional investigation. [ABSTRACT FROM AUTHOR]

Background.A clearer understanding of the basis for the association between cannabis use and psychotic experiences (PEs) is required. Our aim was to examine the extent to which associations between cannabis and cigarette use and PEs are due to confounding.Method.A cohort study of 1756 adolescents with data on cannabis use, cigarette use and PEs.Results.Cannabis use and cigarette use at age 16 were both associated, to a similar degree, with PEs at age 18 [odds ratio (OR) 1.48, 95% confidence interval (CI) 1.18–1.86 for cannabis and OR 1.61, 95% CI 1.31–1.98 for cigarettes]. Adjustment for cigarette smoking frequency (OR 1.27, 95% CI 0.91–1.76) or other illicit drug use (OR 1.25, 95% CI 0.91–1.73) substantially attenuated the relationship between cannabis and PEs. The attenuation was to a lesser degree when cannabis use was adjusted for in the cigarette PE association (OR 1.42, 95% CI 1.05–1.92). However, almost all of the participants used cannabis with tobacco, including those who classed themselves as non-cigarette smokers.Conclusions.Teasing out the effects of cannabis from tobacco is highly complex and may not have been dealt with adequately in studies to date, including this one. Complementary methods are required to robustly examine the independent effects of cannabis, tobacco and other illicit drugs on PEs. [ABSTRACT FROM AUTHOR]

High-quality epitaxial thin films of Jeff = 1/2 Mott insulator Sr2IrO4 with increasing in-plane tensile strain have been grown on top of SrTiO3(001) substrates. Increasing the in-plane tensile strain up to ~0.3% was observed to drop the c/a tetragonality by 1.2%. X-ray absorption spectroscopy detected a strong reduction of the linear dichroism upon increasing in-plane tensile strain towards a reduced anisotropy in the local electronic structure. While the most relaxed thin film shows a consistent dependence with previously reported single crystal bulk measurements, electrical transport reveals a charge gap reduction from 200 meV down to 50 meV for the thinnest and most epitaxy-distorted film. We argue that the reduced tetragonality plays a major role in the change of the electronic structure, which is reflected in the change of the transport properties. Our work opens the possibility for exploiting epitaxial strain as a tool for both structural and functional manipulation of spin-orbit Mott systems. [ABSTRACT FROM AUTHOR]

Abstract: Both prenatal and postnatal maternal depression are independently associated with an increased risk of adverse infant development. The impact of postnatal depression on infants may be mediated through the effect of depression in reducing maternal responsiveness. However, the mechanisms underlying the effect of prenatal depression are unclear. Using longitudinal data from over 900 mother–infant pairs in a UK birth cohort (ALSPAC), we found that women with high depressive symptom scores during mid pregnancy, but NOT when their infants were 8 months, had a 30% increased risk of low maternal responsiveness when the infant was 12 months compared to women with consistently low depression. This may provide a mechanism to explain the independent association between prenatal depression and poorer infant development. [Copyright &y& Elsevier]

Abstract: Current models of short-term visual perceptual memory invoke mechanisms that are closely allied to low-level perceptual discrimination mechanisms. The purpose of this study was to investigate the extent to which human visual perceptual memory for spatial frequency is based upon multiple, spatially tuned channels similar to those found in the earliest stages of visual processing. To this end we measured how performance on a delayed spatial frequency discrimination paradigm was affected by the introduction of interfering or ‘memory masking’ stimuli of variable spatial frequency during the delay period. Masking stimuli were shown to induce shifts in the points of subjective equality (PSE) when their spatial frequencies were within a bandwidth of 1.2 octaves of the reference spatial frequency. When mask spatial frequencies differed by more than this value, there was no change in the PSE from baseline levels. This selective pattern of masking was observed for different spatial frequencies and demonstrates the existence of multiple, spatially tuned mechanisms in visual perceptual memory. Memory masking effects were also found to occur for horizontal separations of up to 6deg between the masking and test stimuli and lacked any orientation selectivity. These findings add further support to the view that low-level sensory processing mechanisms form the basis for the retention of spatial frequency information in perceptual memory. However, the broad range of transfer of memory masking effects across spatial location and other dimensions indicates more long range, long duration interactions between spatial frequency channels that are likely to rely contributions from neural processes located in higher visual areas. [Copyright &y& Elsevier]

Please cite this paper as: Flach C, Leese M, Heron J, Evans J, Feder G, Sharp D, Howard L. Antenatal domestic violence, maternal mental health and subsequent child behaviour: a cohort study. BJOG 2011;118:1383-1391. Objective To investigate the long-term impact of antenatal domestic violence on maternal psychiatric morbidity and child behaviour. Design Cohort study. Setting Avon, UK. Population or sample A birth cohort of 13 617 children and mother dyads were followed to 42 months of age. Methods Experiences of domestic violence and depressive symptoms were gathered at 18 weeks of gestation and up to 33 months after birth, together with maternal, paternal and child characteristics. Main outcome measures Child behavioural problems were assessed at 42 months using the Revised Rutter Questionnaire. Analysis Logistic regression with the use of multiple imputation employing chained equations for missing data. Results Antenatal domestic violence was associated with high levels of maternal antenatal (odds ratio [OR], 4.02; 95% confidence interval [CI], 3.4-4.8) and postnatal (OR, 1.29; 95% CI, 1.02-1.63) depressive symptoms after adjustment for potential confounders. Antenatal domestic violence predicted future behavioural problems at 42 months in the child before adjustment for possible confounding and mediating factors (OR, 1.87; 95% CI, 1.45-2.40); this association was not significant after adjustment for high levels of maternal antenatal depressive symptoms, postnatal depressive symptoms or domestic violence since birth. Conclusions Antenatal domestic violence is associated with high levels of both maternal antenatal and postnatal depressive symptoms. It is also associated with postnatal violence, and both are associated with future behavioural problems in the child at 42 months. This is partly mediated by maternal depressive symptoms in the ante- or postnatal period. [ABSTRACT FROM AUTHOR]

We report on measurements performed at low temperatures on a nanoelectromechanical system (NEMS) under (capacitive) parametric pumping. The excitations and detection schemes are purely electrical and, in the present experiment, enable the straightforward measurement of forces down to about a femtonewton, for displacements of an angström, using standard room-temperature electronics. We demonstrate that a small (linear) force applied on the device can be amplified up to more than a 100 times, while the system is truly moving. We explore the dynamics up to about 50-nm deflections for cantilevers about 200 nm thick and 3 μm long, oscillating at a frequency of 7 MHz. We present a generic modeling of nonlinear parametric amplification and give analytic theoretical solutions enabling the fit of experimental results. We finally discuss the practical limits of the technique, with a particular application: the measurement of anelastic damping in the metallic coating of the device, with an exceptional resolution of about 0.5%. [ABSTRACT FROM AUTHOR]

Abstract: We investigated whether changes in low-level image characteristics, in this case spatial frequency, were capable of generating a well-known expansion in the perceived duration of an infrequent “oddball” stimulus relative to a repeatedly-presented “standard” stimulus. Our standard and oddball stimuli were Gabor patches that differed from each other in spatial frequency by two octaves. All stimuli were equated for visibility. Rather than the expected “subjective time expansion” found in previous studies, we obtained an equal and opposite expansion or contraction of perceived time dependent upon the spatial frequency relationship of the standard and oddball stimulus. Subsequent experiments using equi-visible stimuli reveal that mid-range spatial frequencies (ca. 2c/deg) are consistently perceived as having longer durations than low (0.5c/deg) or high (8c/deg) spatial frequencies, despite having the same physical duration. Rather than forming a fixed proportion of baseline duration, this bias is constant in additive terms and implicates systematic variations in visual persistence across spatial frequency. Our results have implications for the widely cited finding that auditory stimuli are judged to be longer in duration than visual stimuli. [Copyright &y& Elsevier]