238 research outputs found

    Prospective study of family adversity and maladaptive parenting in childhood and borderline personality disorder symptoms in a non-clinical population at 11 years

    Get PDF
    Background Retrospective studies have consistently indicated an association between maladaptive parenting and borderline personality disorder (BPD). This requires corroboration with prospective, longitudinal designs. We investigated the association between suboptimal parenting and parent conflict in childhood and BPD symptoms in late childhood using a prospective sample. Method A community sample of 6050 mothers and their children (born between April 1991 and December 1992) were assessed. Mothers' family adversity was assessed during pregnancy and parenting behaviours such as hitting, shouting, hostility and parent conflict across childhood. Intelligence quotient (IQ) and DSM-IV Axis I diagnoses were assessed at 7–8 years. Trained psychologists interviewed children at 11 years (mean age 11.74 years) to ascertain BPD symptoms. Results After adjustment for confounders, family adversity in pregnancy predicted BPD probable 1 to 2 adversities: odds ratio (OR)=1.34 [95% confidence interval (CI) 1.01–1.77]; >2 adversities: OR 1.99 (95% CI 1.34–2.94) and definite 1 to 2 adversities: OR 2.48 (95% CI 1.01–6.08) symptoms. Each point increase in the suboptimal parenting index predicted BPD probable: OR 1.13 (95% CI 1.05–1.23) and definite: OR 1.28 (95% CI 1.03–1.60) symptoms. Parent conflict predicted BPD probable: OR 1.19 (95% CI 1.06–1.34) and definite: OR 1.42 (95% CI 1.06–1.91) symptoms. Within the path analysis, the association between suboptimal parenting and BPD outcome was partially mediated by DSM-IV diagnoses and IQ at 7–8 years. Conclusions Children from adverse family backgrounds, who experience suboptimal parenting and more conflict between parents, have poor cognitive abilities and a DSM-IV diagnosis, are at increased risk of BPD symptoms at 11 years

    Cannabis use and hypomania in young people: a prospective analysis

    Get PDF
    Background: Cannabis use in young people is common and associated with psychiatric disorders. However, the prospective link between cannabis use and bipolar disorder symptoms has rarely been investigated. The study hypothesis was that adolescent cannabis use is associated with hypomania in early adulthood via several potential etiological pathways. Methods: Data were used from the Avon Longitudinal Study of Parents and Children, a UK birth cohort study. The prospective link between cannabis use at age 17 and hypomania at age 22–23 years was tested using regression analysis, adjusted for gender, early environmental risk factors, alcohol and drug use, and depression and psychotic symptoms at age 18 years. Path analysis examined direct and indirect effects of the link and whether gender, childhood family adversity, or childhood abuse are associated with hypomania via an increased risk of cannabis use. Results: Data were available on 3370 participants. Cannabis use at least 2–3 times weekly was associated with later hypomania (OR = 2.21, 95% CI = 1.49–3.28) after adjustment. There was a dose–response relationship (any use vs weekly). Cannabis use mediated the association of both childhood sexual abuse and hypomania, and male gender and hypomania. The cannabis use-hypomania link was not mediated by depression or psychotic symptoms. Conclusions: Adolescent cannabis use may be an independent risk factor for future hypomania, and the nature of the association suggests a potential causal link. Cannabis use mediates the link between childhood abuse and future hypomania. As such it might be a useful target for indicated prevention of hypomania

    Interpreting Electronic Voice Phenomena: The role of auditory perception, paranormal belief and individual differences

    Get PDF
    Electronic Voice Phenomena are anomalous voices that appear on audio recordings (Barušs, 2001) and various techniques have been suggested for obtaining these voices. People who investigate potentially paranormal, site based anomalies (ghosthunters) have in recent years been using techniques to obtain EVP voices, and declaring them as proof of the paranormal. Previous studies have examined the role of paranormal belief on various personality factors and on cognition, however individuals who use EVP as a technique (high-EVPers) have not previously been studied to ascertain if they differ from both the sceptical population (non-EVPers) and people who believe in the paranormal but who do not use EVP techniques (low-EVPers). The current studies examined personality variable differences between non-, low and high-EVPers. A new questionnaire, the Paranormal Investigation Experience Questionnaire, proved capable of differentiating between non-, low- and high-EVPers, and displayed high reliability. From the current studies, it does not appear that EVPers can be classified as a separate group of individuals when compared with general paranormal believers when comparing personality traits. It is possible to define them as a group based on their experiences of EVP, but this separation is not found when investigating a number of individual difference measures which have been shown to be able to distinguish between general paranormal believers and non-believers. EVPers demonstrated higher levels of sleep related hallucinations, which may have implications for how they are interpreting noise as EVP voices. There was a commonality in auditory test results between a number of personality factors, individuals high in these measures were all more likely to report hearing non-directional voices in noise, which may have implications for how EVPers are interpreting sound clips depending on how they are listening to those clips. High hallucinators reported hallucinated voices in their right ear, which supports previous research. The results suggest that a number of factors are involved in causing misperception of voices in noise, but these results may be applicable to the general population rather than specifically to a population of EVP experiencers. Suggestions as to future research and comparison with other methods of apparent paranormal communication are discussed

    The developmental precursors of borderline personality disorder symptoms at 11 years in a British cohort

    Get PDF
    Borderline Personality Disorder (BPD) is a severe and chronic mental health disorder, affecting many areas of functioning including: affect regulation, impulse control, interpersonal relationships and self-image. Causal factors are only partly known due to a scarcity of prospective, longitudinal studies which enable one to delineate the time ordering of antecedents, and allow for tentative causal inferences. This thesis explored the developmental precursors of BPD symptoms at 11 years, using a British cohort sample, with assessments pertaining to the study child from pregnancy to 11 years of age. Three studies were conducted. Firstly, the predictive relationship between exposure to maladaptive parenting and subsequent BPD symptoms was explored within a child population, using a clinically relevant assessment of BPD symptoms. This association has been previously shown in a range of retrospective studies. Secondly, the role of peer victimisation in the development of BPD was considered. This study was designed to extend current aetiological models, which focus on parental rather than peer relationships. It was based on the recognition of a strong interpersonal core in the BPD symptom constellation, and the role of trauma experiences in the development of BPD. Finally, the third study was designed to consider how these two experiential factors (maladaptive parenting and peer victimisation) might magnify a predisposition towards dysregulation, eventually culminating in BPD symptoms. Data was obtained from the Avon Longitudinal Study of Parents and Children (ALSPAC), which studied 6,050 children (43.1% of the total sample population), using questionnaire and interview assessments. Results revealed that, firstly, family adversity during pregnancy and suboptimal parenting, during early to middle childhood was predictive of BPD symptoms at 11 years. Secondly, peer victimisation during early to late childhood was predictive of BPD symptoms at 11 years. There was an especially strong dose response effect for severe, combined or chronic victimisation. Finally, those evincing stable dysregulated trait behaviour from 4 to 8 years were more likely to develop BPD symptoms, and this effect was especially strong for high levels of dysregulation. Consistent with the biosocial developmental model of BPD, the association was fully mediated by psychosocial risk factors (peer victimisation). Those with high levels of dysregulation were more likely to be victimised and, in turn, develop BPD symptoms. Further, the indirect associations were significantly stronger for BPD, compared to psychotic or depression outcomes. The strengths and weaknesses, along with practical and theoretical implications, and future directions are discussed in the final chapter

    Using min-sum loopy belief propagation for decentralised supply chain formation

    Get PDF
    Modern business trends such as agile manufacturing and virtual corporations require high levels of flexibility and responsiveness to consumer demand, and require the ability to quickly and efficiently select trading partners. Automated computational techniques for supply chain formation have the potential to provide significant advantages in terms of speed and efficiency over the traditional manual approach to partner selection. Automated supply chain formation is the process of determining the participants within a supply chain and the terms of the exchanges made between these participants. In this thesis we present an automated technique for supply chain formation based upon the min-sum loopy belief propagation algorithm (LBP). LBP is a decentralised and distributed message-passing algorithm which allows participants to share their beliefs about the optimal structure of the supply chain based upon their costs, capabilities and requirements. We propose a novel framework for the application of LBP to the existing state-of-the-art case of the decentralised supply chain formation problem, and extend this framework to allow for application to further novel and established problem cases. Specifically, the contributions made by this thesis are: • A novel framework to allow for the application of LBP to the decentralised supply chain formation scenario investigated using the current state-of-the-art approach. Our experimental analysis indicates that LBP is able to match or outperform this approach for the vast majority of problem instances tested. • A new solution goal for supply chain formation in which economically motivated producers aim to maximise their profits by intelligently altering their profit margins. We propose a rational pricing strategy that allows producers to earn significantly greater profits than a comparable LBP-based profitmaking approach. • An LBP-based framework which allows the algorithm to be used to solve supply chain formation problems in which goods are exchanged in multiple units, a first for a fully decentralised technique. As well as multiple-unit exchanges, we also model in this scenario realistic constraints such as factory capacities and input-to-output ratios. LBP continues to be able to match or outperform an extended version of the existing state-of-the-art approach in this scenario. • Introduction of a dynamic supply chain formation scenario in which participants are able to alter their properties or to enter or leave the process at any time. Our results suggest that LBP is able to deal easily with individual occurences of these alterations and that performance degrades gracefully when they occur in larger numbers

    Metal binding to transferrin and immune reactions in Parkinson's disease

    Get PDF
    The binding of iron (59Fe) and gallium (67Ga) to the plasma protein transferrin (Tf) was investigated by G75 gel filtration chromatography in control patients and treated and untreated patients with Parkinson's disease (PD). Fe-Tf binding was 100% in all controls and PD patients suggesting that a defect in Fe-Tf binding was not involved in the aetiology of PD. Ga-Tf binding was significantly reduced in both untreated and treated PD patients compared to controls. In addition, treated PD patients had significantly higher Ga-Tf binding than untreated patients. A reduction in metal binding to Tf could result in the increase of a low molecular weight species which may more readily enter the CNS. Alternatively, it could lead to a decrease in the transport of essential metals into the brain via the Tf receptor system. A significant elevation in neopterin was demonstrated within the plasma of untreated PD patients compared to controls suggesting the activation of a cellular immune response. Furthermore, plasma neopterin was lower in treated compared to untreated PD patients, although the difference was not significant. There was no evidence for the activation of the humoral immune response in untreated or treated PD patients as measured by circulating immune complex (CIC) levels within the plasma. An inverse relationship between Ga-Tf binding and neopterin was observed in untreated PD patients. The addition of oxidants in the form of potassium permanganate and activated manganese dioxide reduced Ga-Tf binding in control plasma. However, relatively little response was observed using monocyte preparations. The results suggest that oxidants produced by activation of the cellular immune system could damage the Tf molecule thereby reducing its ability to bind metals

    Decentralized supply chain formation using max-sum loopy belief propagation

    Get PDF
    Supply chain formation is the process by which a set of producers within a network determine the subset of these producers able to form a chain to supply goods to one or more consumers at the lowest cost. This problem has been tackled in a number of ways, including auctions, negotiations, and argumentation-based approaches. In this paper we show how this problem can be cast as an optimization of a pairwise cost function. Optimizing this class of energy functions is NP-hard but efficient approximations to the global minimum can be obtained using loopy belief propagation (LBP). Here we detail a max-sum LBP-based approach to the supply chain formation problem, involving decentralized message-passing between supply chain participants. Our approach is evaluated against a well-known decentralized double-auction method and an optimal centralized technique, showing several improvements on the auction method: it obtains better solutions for most network instances which allow for competitive equilibrium (Competitive equilibrium in Walsh and Wellman is a set of producer costs which permits a Pareto optimal state in which agents in the allocation receive non-negative surplus and agents not in the allocation would acquire non-positive surplus by participating in the supply chain) while also optimally solving problems where no competitive equilibrium exists, for which the double-auction method frequently produces inefficient solutions. © 2012 Wiley Periodicals, Inc

    Associations between infant and toddler regulatory problems, childhood co-developing internalising and externalising trajectories, and adolescent depression, psychotic and borderline personality disorder symptoms

    Get PDF
    Background Early regulatory problems (RPs) are associated with childhood internalising and externalising symptoms. Internalising and externalising symptoms, in turn, are associated with adolescent psychopathology (e.g. personality disorders, depression). We examined whether RPs are directly associated with adolescent psychopathology, or whether associations are indirect via childhood internalising and externalising symptoms. Methods We used data from the Avon Longitudinal Study of Parents and Children. Mothers reported on their child's RPs at 6, 15–18 and 24–30 months, and internalising and externalising symptoms at 4, 7, 8 and 9.5 years. Adolescent psychotic, depression and BPD symptoms were assessed at 11–12 years. Children were grouped by their patterns of co‐developing internalising and externalising symptoms using parallel process latent class growth analysis (PP‐LCGA). Path analysis was used to examine direct and indirect associations from RPs to the three adolescent outcomes. Results There were four groups of children with distinct patterns of co‐developing internalising and externalising (INT/EXT) symptoms. Most children (53%) demonstrated low–moderate and stable levels of INT/EXT symptoms. A small proportion (7.7%) evidenced moderate and increasing INT and high stable EXT symptoms: this pattern was strongly predictive of adolescent psychopathology (e.g. depression at 11 years: unadjusted odds ratio = 5.62; 95% confidence intervals = 3.82, 8.27). The other two groups were differentially associated with adolescent outcomes (i.e. moderate–high increasing INT/moderate decreasing EXT predicted mother‐reported depression at 12, while low stable INT/moderate–high stable EXT predicted child‐reported depression at 11). In path analysis, RPs at each time‐point were significantly indirectly associated with symptoms of BPD and child‐ and mother‐reported depression symptoms via the most severe class of INT/EXT symptoms. Conclusions Consistent with a cascade model of development, RPs are predictive of higher levels of co‐developing INT/EXT symptoms, which in turn increase risk of adolescent psychopathology. Clinicians should be aware of, and treat, early RPs to prevent chronic psychopathology

    Using min-sum loopy belief propagation for decentralised supply chain formation

    Get PDF
    Modern business trends such as agile manufacturing and virtual corporations require high levels of flexibility and responsiveness to consumer demand, and require the ability to quickly and efficiently select trading partners. Automated computational techniques for supply chain formation have the potential to provide significant advantages in terms of speed and efficiency over the traditional manual approach to partner selection. Automated supply chain formation is the process of determining the participants within a supply chain and the terms of the exchanges made between these participants. In this thesis we present an automated technique for supply chain formation based upon the min-sum loopy belief propagation algorithm (LBP). LBP is a decentralised and distributed message-passing algorithm which allows participants to share their beliefs about the optimal structure of the supply chain based upon their costs, capabilities and requirements. We propose a novel framework for the application of LBP to the existing state-of-the-art case of the decentralised supply chain formation problem, and extend this framework to allow for application to further novel and established problem cases. Specifically, the contributions made by this thesis are: • A novel framework to allow for the application of LBP to the decentralised supply chain formation scenario investigated using the current state-of-the-art approach. Our experimental analysis indicates that LBP is able to match or outperform this approach for the vast majority of problem instances tested. • A new solution goal for supply chain formation in which economically motivated producers aim to maximise their profits by intelligently altering their profit margins. We propose a rational pricing strategy that allows producers to earn significantly greater profits than a comparable LBP-based profitmaking approach. • An LBP-based framework which allows the algorithm to be used to solve supply chain formation problems in which goods are exchanged in multiple units, a first for a fully decentralised technique. As well as multiple-unit exchanges, we also model in this scenario realistic constraints such as factory capacities and input-to-output ratios. LBP continues to be able to match or outperform an extended version of the existing state-of-the-art approach in this scenario. • Introduction of a dynamic supply chain formation scenario in which participants are able to alter their properties or to enter or leave the process at any time. Our results suggest that LBP is able to deal easily with individual occurences of these alterations and that performance degrades gracefully when they occur in larger numbers.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
    corecore