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In recent years, the discovery of massive quasars at
has provided a striking challenge to our understanding of the origin and growth of supermassive black holes in the early Universe. Mounting observational and theoretical evidence indicates the viability of massive seeds, formed by the collapse of supermassive stars, as a progenitor model for such early, massive accreting black holes. Although considerable progress has been made in our theoretical understanding, many questions remain regarding how (and how often) such objects may form, how they live and die, and how next generation observatories may yield new insight into the origin of these primordial titans. This review focusses on our present understanding of this remarkable formation scenario, based on the discussions held at the Monash Prato Centre from November 20 to 24, 2017, during the workshop ‘Titans of the Early Universe: The Origin of the First Supermassive Black Holes’.
Mitochondrial dysfunction and resulting changes in adiposity have been observed in the offspring of animals fed a high fat (HF) diet. As iron is an important component of the mitochondria, we have studied the offspring of female rats fed complete (Con) or iron-deficient (FeD) rations for the duration of gestation to test for similar effects. The FeD offspring were ~12% smaller at weaning and remained so because of a persistent reduction in lean tissue mass. The offspring were fed a complete (stock) diet until 52 weeks of age after which some animals from each litter were fed a HF diet for a further 12 weeks. The HF diet increased body fat when compared with animals fed the stock diet, however, prenatal iron deficiency did not change the ratio of fat:lean in either the stock or HF diet groups. The HF diet caused triglyceride to accumulate in the liver, however, there was no effect of prenatal iron deficiency. The activity of the mitochondrial electron transport complexes was similar in all groups including those challenged with a HF diet. HF feeding increased the number of copies of mitochondrial DNA and the prevalence of the D-loop mutation, however, neither parameter was affected by prenatal iron deficiency. This study shows that the effects of prenatal iron deficiency differ from other models in that there is no persistent effect on hepatic mitochondria in aged animals exposed to an increased metabolic load.
Background: The evidence regarding whether co-morbid obsessive compulsive personality disorder (OCPD) is associated with treatment outcomes in obsessive compulsive disorder (OCD) is mixed, with some research indicating that OCPD is associated with poorer response, and some showing that it is associated with improved response. Aims: We sought to explore the role of OCPD diagnosis and the personality domain of conscientiousness on treatment outcomes for exposure and response prevention for OCD. Method: The impact of co-morbid OCPD and conscientiousness on treatment outcomes was examined in a clinical sample of 46 participants with OCD. Results: OCPD diagnosis and scores on conscientiousness were not associated with poorer post-treatment OCD severity, as indexed by Yale-Brown Obsessive Compulsive Scale (YBOCS) scores, although the relative sample size of OCPD was small and thus generalizability is limited. Conclusion: This study found no evidence that OCPD or conscientiousness were associated with treatment outcomes for OCD. Further research with larger clinical samples is required.
The purpose of this article is to review some recent attempts to understand the origin of globular clusters. To put this in perspective, it may help to recall the analogous problem of the origin of galaxies. This splits into two parts. First, given a proto-galaxy with a specified mass and radius, how does it collapse, form stars and settle into a state of dynamical equilibrium? Richard Larson explored these topics in an important series of numerical simulations in the 1970s. Progress in this area brings into sharper focus a second set of questions that really has precedence over the first. Why did proto-galaxies have properties like the initial conditions in the collapse calculations and what distinguishes galaxies from structures on much larger and much smaller scales? Similar questions face us when we consider the origin of globular clusters. First, how did stars form in a proto-cluster, what was the efficiency, the initial mass function and so forth? It is appropriate that Larson has discussed these topics in the preceding article but here we are mainly concerned with the second kind of question: What is special about objects with masses of order 105-106 M⊙ and dimensions of a few tens of parsecs?
Perfectionism is a risk and maintaining factor across psychopathology and has been proposed to be a transdiagnostic process. The aim of this study was to examine the reliability and validity of the Clinical Perfectionism Questionnaire (CPQ) in 32 adults (75% female, M age = 35.54 years, SD = 9.71) with a range of psychological disorders, presenting for treatment of clinical perfectionism. There was evidence that the CPQ was correlated with established measures of perfectionism and theoretically related constructs including self-criticism and dichotomous thinking. The CPQ was also able to predict treatment outcome. The internal consistency was not adequate in the current study; however, the sample size was small. Future studies should examine the psychometric properties of the CPQ in a larger sample of individuals with a range of psychological disorders.
The possibility that life, primitive or advanced, might exist in other places of the Universe has occupied the minds of scientists and lay-people for thousands of years. It is only in the last 25 years, however, that we have finally begun to search for answers to this profound question using experimental techniques. The goal of Astronomy is to understand the origin and evolution of planets, stars, galaxies and of the Universe as a whole. The appearance of life is an integral part of this whole process and our picture of the Universe will never be complete until we will comprehend also the significance of life in the process of Cosmic Evolution.
In view of the broad range of topics covered by Commission U8 and the consequent inevitable overlap with other commissions, it/is not feasible to produce a comprehensive self-contained report. The commission therefore restricts its report to a selected list of accessible recent review articles and conference reports, wherein up-todate summaries of various topics can be found. Such a list is given below. A special report by I. S. Shklovsky on work done in the Soviet Union follows.
Using semi-empirical isochrones, we find the age of the Taurus star-forming region to be 3-4 Myr. Comparing the disc fraction in Taurus to young massive clusters suggests discs survive longer in this low density environment. We also present a method of photometrically de-reddening young stars using iZJH data.
Background: Improving mental health literacy in the general population is important as it is associated with early detection and treatment-seeking for mental health problems. Target areas for mental health literacy programs should be guided by research that tests the impact of improving knowledge of psychological constructs associated with the development of mental health problems. Aims: This study investigated the impact of providing corrective information about the nature of intrusive thoughts on their subsequent appraisal in a community sample. Method: In an online, experimental design, 148 community participants completed measures of obsessive-compulsive symptoms and appraisals (Obsessive Compulsive Inventory-Revised [OCI-R]; Intrusions Inventory [III]). Individuals were instructed to read either a brief informational text about the nature of intrusive thoughts or a control text. All participants then completed post-test measurements of appraisals. Intervention effectiveness was analysed using hierarchical multiple regression. Results: Individuals in the intervention group reported significantly lower levels of maladaptive appraisals than those in the control group (α = .05). Conclusions: The results of this study support the efficacy of provision of brief written information in reducing negative appraisals of intrusive thoughts in a community sample. It suggests a possible role for education about intrusive thoughts as a prevention strategy for obsessive-compulsive disorder.
Depressive symptoms are prominent psychopathological features of Huntington's disease (HD), making a negative impact on social functioning and well-being.
We compared the frequencies of a history of depression, previous suicide attempts and current subthreshold depression between 61 early-stage HD participants and 40 matched controls. The HD group was then split based on the overall HD group's median Hospital Anxiety and Depression Scale-depression score into a group of 30 non-depressed participants (mean 0.8, s.d. = 0.7) and a group of 31 participants with subthreshold depressive symptoms (mean 7.3, s.d. = 3.5) to explore the neuroanatomy underlying subthreshold depressive symptoms in HD using voxel-based morphometry (VBM) and diffusion tensor imaging (DTI).
Frequencies of history of depression, previous suicide attempts or current subthreshold depressive symptoms were higher in HD than in controls. The severity of current depressive symptoms was also higher in HD, but not associated with the severity of HD motor signs or disease burden. Compared with the non-depressed HD group DTI revealed lower fractional anisotropy (FA) values in the frontal cortex, anterior cingulate cortex, insula and cerebellum of the HD group with subthreshold depressive symptoms. In contrast, VBM measures were similar in both HD groups. A history of depression, the severity of HD motor signs or disease burden did not correlate with FA values of these regions.
Current subthreshold depressive symptoms in early HD are associated with microstructural changes – without concomitant brain volume loss – in brain regions known to be involved in major depressive disorder, but not those typically associated with HD pathology.
This editorial proposes a shift in emphasis in the field of mental health epidemiology in conflict-affected settings. After a brief summary of the nature of contemporary armed conflicts, we consider the current and potential roles that epidemiology can play with regard to: (1) establishing the burden of mental disorders; (2) identifying risk and protective factors; and (3) intervention research. We advocate for improved methodological rigor; more attention to mixed methods approaches and multi-level longitudinal research; inclusion of the determinants of mental health beyond conflict-related violence; and consideration of a wider array of mental health outcomes. We particularly highlight the importance of expanding interest to epidemiological research that advances prevention and promotion interventions (e.g., in the early childhood period), in order to fill the gap between epidemiology and mental health practice in conflict-affected settings.
Background: Clinical perfectionism is a transdiagnostic process that has been found to maintain eating disorders, anxiety disorders and depression. Cognitive behavioural models explaining the maintenance of clinical perfectionism emphasize the contribution of dichotomous thinking and resetting standards higher following both success and failure in meeting their goals. There has been a paucity of research examining the predictions of the models and motivation to change perfectionism. Motivation to change is important as individuals with clinical perfectionism often report many perceived benefits of their perfectionism; they are, therefore, likely to be ambivalent regarding changing perfectionism. Aims: The aim was to compare qualitative responses regarding questions about motivation to change standards and cognitions regarding failure to meet a personal standard in two contrasting groups with high and low negative perfectionism. Negative perfectionism refers to concern over not meeting personal standards. Method: A clinical group with a range of axis 1 diagnoses who were elevated on negative perfectionism were compared to a group of athletes who were low on negative perfectionism. Results: Results indicated that the clinical group perceived many negative consequences of their perfectionism. They also, however, reported numerous benefits and the majority stated that they would prefer not to change their perfectionism. The clinical group also reported dichotomous thinking and preferring to either keep standards the same or reset standards higher following failure, whilst the athlete group reported they would keep standards the same or set them lower. Conclusions: The findings support predictions of the cognitive behavioural model of clinical perfectionism.
Background: Magical thinking has been proposed to have an aetiological role in obsessive compulsive disorder (OCD). Aims: To address the limitations of existing measures of magical thinking we developed and validated a new 24-item measure of magical thinking, the Illusory Beliefs Inventory (IBI). Method: The validation sample comprised a total of 1194 individuals across two samples recruited via an Internet based survey. Results: Factor analysis identified three subscales representing domains relevant to the construct of magical thinking: Magical Beliefs, Spirituality, and Internal State and Thought Action Fusion. The scale had excellent internal consistency and evidence of convergent and discriminant validity. Evidence of criterion-related concurrent validity confirmed that magical thinking is a cognitive domain associated with OCD and is largely relevant to neutralizing, obsessing and hoarding symptoms. Conclusions: It is important for future studies to extend the evidence of the psychometric properties of the IBI in new populations and to conduct longitudinal studies to examine the aetiological role of magical thinking.
Perfectionism has been suggested as a risk factor for the development of stress and burnout in psychotherapists, but this has not been extensively investigated. This study examined the relationship between perfectionism, stress and burnout in 87 Australian clinical psychologists. Stress had significant influences on the relationship between perfectionism and burnout. Specifically, stress was found to be a partial intervening variable in the relationship between perfectionism and personal burnout. In addition, stress was also found to completely mediate the influence of perfectionism on work-related and client-related burnout. The results indicated that perfectionism was both directly and indirectly related through stress to various types of burnout in clinical psychologists. Implications of the findings for research in to the utility of intervention for high levels of perfectionism in clinical psychologists are discussed.
A 2,3-dibutoxy-1,4-phenylenevinylene comonomer was incorporated into a distyrylbenzene derivative 11. Novel 1,2-disubstituted-3,6-dibromobenzene comonomers 15 and 18 were prepared by directed metallation. Copolymerization of 11with a 9,9-dioctylfluorene-2,7-diboronate ester 1 yielded a green fluorescent polymer while copolymerization of 15 and 18 with the 9,9-dihexylfluorene-2,7-diboronate 22 afforded promising blue fluorescent polymers 23 and 24 respectively.
Growth of ZnSe on GaAs from H2S9 and Zn[N(TMS)2]2 precursors has been demonstrated. When Et2Zn is used as the zinc precursor a higher quality deposit is obtained. Results of experiments employing Et2Zn as the main zinc source with Zn[N(TMS)2]2 introduced at a dopant level indicate nitrogen has been incorporated. Final thin films were characterized by PL, XRD, SIMS, and Raman.
Reaction of Et2AIOEt with ethylene glycol or catechol produced polymers of the general form -[-AI(OEt)-O-R-O-]-n, for R = CH2CH2 or C6H4, respectively. Pyrolytic conversion of these polymers to ceramic materials produced A12O3, at mild (∼500°C) temperatures under a flowing atmosphere of dry air. The crystal phase obtained from the thermolysis is highly dependent upon the degree of cross-linking present in the initial polymer. These results are discussed in terms of the required solid-state atomic reorganization necessary to proceed from polymer to ceramic.