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The prevalence of common mental disorders has not declined in high-income countries despite substantial increases in service provision. A possible reason for this lack of improvement is that greater willingness to disclose mental disorders might have led to increased reporting of psychiatric symptoms, thus masking reductions in prevalence. This masking hypothesis was tested using data from two trials of interventions that increased willingness to disclose and that also measured symptoms. Both interventions involved Mental Health First Aid (MHFA) training, which is known to reduce stigma, including unwillingness to disclose a mental health problem.
A cross-lagged panel analysis was carried out on data from two large Australian randomised controlled trials of MHFA training. The first trial involved 1643 high school students in Year 10 (mean age 15.87 years), who were randomised to receive either teen MHFA training or physical first aid training as the control. The second trial involved 608 Australia public servants who were randomised to receive either eLearning MHFA, blended eLearning MHFA or eLearning physical first aid as the control. In both trials, willingness to disclose a mental disorder as described in vignettes and psychiatric symptoms (K6 scale) were measured pre-training, post-training and at 12-month follow-up.
Both trials found that MHFA training increased willingness to disclose. However, a cross-lagged panel analysis showed no effect of this change on psychiatric symptom scores.
Greater willingness to disclose did not affect psychiatric symptom scores. Because the trials increased willingness to disclose through a randomly assigned intervention, they provide a strong causal test of the masking hypothesis. It is therefore unlikely that changes in willingness to disclose are masking reductions in prevalence in the population.
Theory of mind, the ability to represent the mental states of others, is an important social cognitive process, which contributes to the development of social competence. Recent research suggests that interactions between gene and environmental factors, such as oxytocin receptor gene (OXTR) polymorphisms and maternal parenting behavior, may underlie individual differences in children's theory of mind. However, the potential influence of DNA methylation of OXTR remains unclear. The current study investigated the roles of OXTR methylation, maternal behavior, and their statistical interaction on toddlers’ early emerging theory of mind abilities. Participants included a community sample of 189 dyads of mothers and their 2- to 3-year-old children, whose salivary DNA was analyzed. Results indicated that more maternal structuring behavior was associated with better performance, on a battery of three theory of mind tasks, while higher OXTR methylation within exon 3 was associated with poorer performance. A significant interaction also emerged, such that OXTR methylation was related to theory of mind among children whose mothers displayed less structuring, when controlling for children's age, sex, ethnicity, number of child-aged siblings, verbal ability, and maternal education. Maternal structuring behavior may buffer the potential negative impact of hypermethylation on OXTR gene expression and function.
Invasive rodents detrimentally affect native bird species on many islands worldwide, and rodent eradication is a useful tool to safeguard endemic and threatened species. However, especially on tropical islands, rodent eradications can fail for various reasons, and it is unclear whether the temporary reduction of a rodent population during an unsuccessful eradication operation has beneficial effects on native birds. Here we examine the response of four endemic land bird species on subtropical Henderson Island in the Pitcairn Island Group, South Pacific Ocean, following an unsuccessful rodent eradication in 2011. We conducted point counts at 25 sampling locations in 14 survey periods between 2011 and 2015, and modelled the abundance trends of all species using binomial mixture models accounting for observer and environmental variation in detection probability. Henderson Reed Warbler Acrocephalus taiti more than doubled in abundance (2015 population estimate: 7,194-28,776), and Henderson Fruit Dove Ptilinopus insularis increased slightly between 2011 and 2015 (2015 population estimate: 4,476–10,072), while we detected no change in abundance of the Henderson Lorikeet Vini stepheni (2015 population estimate: 554–3014). Henderson Crake Zapornia atra increased to pre-eradication levels following anticipated mortality during the operation (2015 population estimate: 4,960–20,783). A temporary reduction of rat predation pressure and rat competition for fruit may have benefitted the reed warbler and the fruit dove, respectively. However, a long drought may have naturally suppressed bird populations prior to the rat eradication operation in 2011, potentially confounding the effects of temporary rat reduction and natural recovery. We therefore cannot unequivocally ascribe the population recovery to the temporary reduction of the rat population. We encourage robust monitoring of island biodiversity both before and after any management operation to better understand responses of endemic species to failed or successful operations.
Providing benefits to local people from forest conservation programmes is an important issue for policy makers. Livelihood projects are a common way to provide benefits, but there is little information about their costs. We analysed 463 livelihood projects in the Ankeniheny-Zahamena Corridor Reducing Emissions from Deforestation and Degradation (REDD+) pilot project in Madagascar to understand how different approaches to delivering livelihood projects affect costs. We compared costs across four approaches: conservation agreements, small grants, direct implementation and application of social safeguards. The approach impacted overall costs and the proportion of funds reaching communities. Projects implemented as safeguards were most expensive and had the lowest proportion of expenditures reaching the community. Projects provided as part of conservation agreements directed the highest proportion of expenditures to communities. Our results highlight that how livelihood projects are delivered has implications for project costs and community benefits and should be an important consideration in the design and implementation of REDD+ and forest conservation policies.
Direct solar flare neutrons are a valuable diagnostic of high-energy ion acceleration in these events, and COMPTEL improves over all previous cosmic neutron detectors in its capacity for neutron energy measurement. Previous studies of COMPTEL neutron data have worked with an incomplete model of the instrumental response, applying energy-by-energy detection efficiencies. Here we employ statistical regularisation techniques with the full (Monte Carlo simulation derived) response matrix to produce improved estimates of neutron numbers and energy distribution. These techniques are applied to data from the well-observed 15 June 1991 flare. Our improved treatment of the instrumental response results in a reduction of 73% in total neutron numbers, compared with previously deduced values. Implications for the picture of primary ion acceleration in this flare are briefly discussed.
Few studies have examined the experiences of carers of people with psychosis using a representative sample. Aiming to obtain generalisable results concerning carers in the context of increased emphasis on involving carers in Australian mental health service delivery and policy frameworks, this study recruited carers within the second Australian national survey of psychotic disorders (Survey of High Impact Psychosis, SHIP). Given that most SHIP participants had long-term illness and extended relationships with carers, the health and wellbeing of carers as a group were expected to be relatively stable. However, since it is unknown whether carers’ health and wellbeing would change, our main aim was to explore change and stability in carers’ health and wellbeing and the relationship between any changes experienced by individual carers and corresponding SHIP participants’ functioning over time.
Ninety-eight caregivers of SHIP participants were recruited at baseline and completed validated instruments assessing their health and wellbeing. Seventy-eight carers were re-interviewed at 1-year follow-up. Clinical factors were extracted from the SHIP database. Wilcoxon matched-pairs signed-rank test and t-test were used to analyse changes in variables over time. Cross-lagged analyses were conducted to identify possible causative relationships in changes in SHIP participant and carer variables.
A substantial percentage of carers experienced social isolation (28.6%), psychological distress (37.7%) and poorer quality of life than population norms. There were no statistically significant changes between baseline and follow-up scores for almost all carers’ health and wellbeing variables, other than a poorer perception of their quality of life in relation to their physical health after 1 year. Cross-lagged analyses suggested that poorer functioning of people with psychosis influenced carers’ social isolation, grief and psychological distress.
Findings show that carers’ perception of their health and wellbeing did not improve within current mental health service delivery frameworks over time. Carer's persistently poor health and wellbeing suggests a pressing need to enhance services that improve carers’ health and wellbeing especially their physical health and the functioning of people with psychosis whom they support.
It is well known that web-based interventions can be effective treatments for depression. However, dropout rates in web-based interventions are typically high, especially in self-guided web-based interventions. Rigorous empirical evidence regarding factors influencing dropout in self-guided web-based interventions is lacking due to small study sample sizes. In this paper we examined predictors of dropout in an individual patient data meta-analysis to gain a better understanding of who may benefit from these interventions.
A comprehensive literature search for all randomized controlled trials (RCTs) of psychotherapy for adults with depression from 2006 to January 2013 was conducted. Next, we approached authors to collect the primary data of the selected studies. Predictors of dropout, such as socio-demographic, clinical, and intervention characteristics were examined.
Data from 2705 participants across ten RCTs of self-guided web-based interventions for depression were analysed. The multivariate analysis indicated that male gender [relative risk (RR) 1.08], lower educational level (primary education, RR 1.26) and co-morbid anxiety symptoms (RR 1.18) significantly increased the risk of dropping out, while for every additional 4 years of age, the risk of dropping out significantly decreased (RR 0.94).
Dropout can be predicted by several variables and is not randomly distributed. This knowledge may inform tailoring of online self-help interventions to prevent dropout in identified groups at risk.
Background: Health anxiety is common, impairing, and costly. The role of catastrophizing of bodily sensations (i.e. rumination about, overconcern with, and intolerance of bodily sensations) in maintaining health-related anxiety (i.e. anxiety about perceived health problems) is important, but understudied, in the health anxiety literature. Aims: The present study investigates the role of catastrophizing of bodily sensations as a maintenance factor for health-related anxiety over time. Method: Undergraduates (n = 226 women; n = 226 men) completed a baseline assessment, 14-day daily diary study, and 14-day longitudinal follow-up. Results: Path analysis indicated catastrophizing of bodily sensations maintains health-related anxiety from one month to the next in both men and women. Conclusions: The present study bridges an important gap between theory and evidence. Results support cognitive behavioral theories and extend cross-sectional research asserting catastrophizing of bodily sensations maintains health-related anxiety over time. A cyclical, self-perpetuating pattern was observed in the present study wherein catastrophizing of bodily sensations and health-related anxiety contribute to one another over time. Results also suggest targeting catastrophizing of bodily sensations may reduce health-related anxiety.
There are insufficient data from nationwide surveys on the prevalence of specific psychotic disorders and associated co-morbidities.
The 2010 Australian national psychosis survey used a two-phase design to draw a representative sample of adults aged 18–64 years with psychotic disorders in contact with public treatment services from an estimated resident population of 1 464 923 adults. This paper is based on data from 1642 participants with an International Classification of Diseases (ICD)-10 psychotic disorder. Its aim is to present estimates of treated prevalence and lifetime morbid risk of psychosis, and to describe the cognitive, physical health and substance use profiles of participants.
The 1-month treated prevalence of psychotic disorders was 3.10 cases per 1000 population aged 18–64 years, not accounting for people solely accessing primary care services; lifetime morbid risk was 3.45 per 1000. Mean premorbid intelligence quotient was approximately 0.5 s.d.s below the population mean; current cognitive ability (measured with a digit symbol coding task) was 1.6 s.d.s below the population mean. For both cognitive tests, higher scores were significantly associated with better independent functioning. The prevalence of the metabolic syndrome was high, affecting 60.8% of participants, and pervasive across diagnostic groups. Of the participants, two-thirds (65.9%) were current smokers, 47.4% were obese and 32.4% were sedentary. Of the participants, half (49.8%) had a lifetime history of alcohol abuse/dependence and 50.8% lifetime cannabis abuse/dependence.
Our findings highlight the need for comprehensive, integrative models of recovery to maximize the potential for good health and quality of life for people with psychotic illness.
High resolution TEM images of boron carbide (B13C2) have been recorded and compared with images calculated using the multislice method as implemented by M. A. O'Keefe in the SHRLI programs. Images calculated for the  zone, using machine parameters for the JEOL 2000FX AEM operating at 200 keV, indicate that for the structure model of Will et al., the optimum defocus image can be interpreted such that white spots correspond to B12 icosahedra for thin specimens and to low density channels through the structure adjacent to the direct inter-icosahedral bonds for specimens of intermediate thickness (-40 > t > -100 nm). With this information, and from the symmetry observed in the TEM images, it is likely that the (101) twin plane passes through the center of icosahedron located at the origin. This model was tested using the method of periodic continuation. Resulting images compare favorably with experimental images, thus supporting the structural model. The introduction of a (101) twin plane through the origin creates distortions to the icosahedral linkages as well as to the intra-icosahedral bonding. This increases the inequivalence of adjacent icosahedral sites along the twin plane, and thereby increases the likelihood of bipolaron hopping.
Detailed analytical electron microscope (AEM) studies of yellow whiskers produced by chemical vapor deposition (CVD)1 show that two basic types of whiskers are produced at low temperatures (between 1200°C and 1400°C) and low boron to carbon gas ratios. Both whisker types show planar microstructures such as twin planes and stacking faults oriented parallel to, or at a rhombohedral angle to, the growth direction. For both whisker types, the presence of droplet-like terminations containing both Si and Ni indicate that the growth process during CVD is via a vapor-liquid-solid (VLS) mechanism.
Boron carbides exhibit an anomalously large Seebeck coefficient with a temperature coefficient that is characteristic of polaronic hopping between inequivalent sites. The inequivalence in the sites is associated with disorder in the solid. The temperature dependence of the Seebeck coefficient for materials prepared by different techniques provides insight into the nature of the disorder.
Visual impairment is a leading cause of morbidity and poor quality of life in our community. Unravelling the mechanisms underpinning important blinding diseases could allow preventative or curative steps to be implemented. Twin siblings provide a unique opportunity in biology to discover genes associated with numerous eye diseases and ocular biometry. Twins are particularly useful for quantitative trait analysis through genome-wide association and linkage studies. Although many studies involving twins rely on twin registries, we present our approach to the Twins Eye Study in Tasmania to provide insight into possible recruitment strategies, expected participation rates and potential examination strategies that can be considered by other researchers for similar studies. Five separate avenues for cohort recruitment were adopted: (1) piggy-backing existing studies where twins had been recruited, (2) utilizing the national twin registry, (3) word-of-mouth and local media publicity, (4) directly approaching schools, and finally (5) collaborating with other research groups studying twins.
Sociometric status differences in children's social competence were examined in a sample of elementary school-aged children using teacher ratings and peer nominations. Rejected children evinced significantly fewer competencies (e.g., peer group entry, responses to provocation) than popular, average, or neglected children but differed from controversial children only with respect to their inability to meet established social norms for cooperative behavior and teachers' expectations for classroom behavior. An examination of the heterogeneity of peer-rejected children revealed that rejected-aggressive children were deficient in all aspects of social competence assessed and were most disliked by their peers. Rejected-withdrawn children were seen by peers as most unhappy, whereas rejected-undifferentiated children (i.e., rejected children who were neither highly aggressive nor highly withdrawn) had problems with social withdrawal, disruptive behavior, and socially appropriate behavior. Rejected-aggressive and rejected-withdrawn children had more difficulties with reactive aggression combined with an inability to respond positively to peers than their nonrejected agemates. The need for further research on the heterogeneity of peer-rejected children and the long-term implications for these children are discussed.
Due to their particular properties (low emittance, short duration, and
large number density), the beams of multi-MeV protons generated during the
interaction of ultraintense (I > 1019 W/cm2)
short pulses with thin solid targets are suited for use as a particle
probe in laser-plasma experiments. When traversing a sample, the proton
density distribution is, in general, affected by collisional stopping,
scattering and deflections via electromagnetic fields, and each of these
effects can be used for diagnostic purposes. In particular, in the limit
of very thin targets, the proton beams represent a valuable diagnostic
tool for the detection of quasi-static electromagnetic fields. The proton
imaging and deflectometry techniques employ these beams, in a
point-projection imaging scheme, as an easily synchronizable diagnostic
tool in laser- plasma interactions, with high temporal and spatial
resolution. By providing diagnostic access to electro-magnetic field
distributions in dense plasmas, this novel diagnostics opens up to
investigation a whole new range of unexplored phenomena. Several transient
processes were investigated employing this technique, via the detection of
the associated electric fields. Examples provided in this paper include
the detection of pressure-gradient electric field in extended plasmas, and
the study of the electrostatic fields associated to the emission of MeV
proton beams in high-intensity laser-foil interactions.
Laurier L. Schramm, Petroleum Recovery Institute and Chemistry Dept., University of Calgary, Calgary, AB, Canada T2L 2A6,
Elaine N. Stasiuk, Petroleum Recovery Institute and Chemistry Dept., University of Calgary, Calgary, AB, Canada T2L 2A6,
Mike MacKinnon, Syncrude Canada Ltd., Research Dept., Edmonton, AB, Canada
In the surface processing of oil sands, surface and interfacial phenomena involving surfactants are involved in the occurrence and properties of suspensions, emulsions, and foams of several kinds. The actions of natural surfactants originating in the bitumen, and underlying the physical chemical basis for the separation process, are reviewed in the context of individual process steps. Issues arising from the occurrence of these surfactants in the process tailings basins are also discussed.
Slurry conditioning of oil sand and the subsequent flotation recovery of separated bitumen comprise what is known as the hot water flotation process for Canada's Athabasca oil sands, a large-scale commercial application of mined oil sands technology. As will be seen, the hot water flotation process is composed of numerous inter-linked elementary process steps many of which are rich in surfactant chemistry. We will review aspects of the surfactant science underlying this process. But first, a few words on oil sands and their early exploitation.
Oil sands are unconsolidated sandstone deposits containing a very heavy crude oil termed bitumen. Bitumen is chemically similar to conventional crude oil but has a greater density (a lower API gravity) and a much greater viscosity. Deposits of oil sand are present in many locations around the world and they appear to be similar in many respects, occurring along the rim of major sedimentary basins, mainly in either fluviatile or deltaic environments containing sands of high porosity and permeability.
Crossbreeding parameters and variance components were estimated for lactation and reproductive traits of crosses between the Sahiwal, Brown Swiss and Ayrshire breeds in a dairy herd in sub-humid coastal Kenya. An individual animal model urns fitted to the data with a fixed effect for 20 distinct breed crosses. The estimates of breed cross means were then regressed on average breed content, expected average heterozygosity and recombination loss to determine the additive breed contributions, and the contributions of dominance and epistasis to heterosis. It was estimated that the Sahiwal contributed about 1345 kg (proportionally 0·33) less milk per lactation than the Brown Swiss. The Ayrshire was intermediate. The large amount of heterosis from the crosses of the Sahiwal (Bos indicusj and Bos taurus breeds more than compensated for the lower additive value of the Sahiwal when used in a three-breed rotational cross or synthetic. Heterosis amotig Bos taurus breeds was negligible. Estimates of the maternal heterosis and recombination loss (epistasis) were not significant, although the latter were consistently large and positive. It was concluded that the heterosis between the zebu and European breeds was mainly due to dominance effects. Estimates of heritability for milk yield traits were low (around 0·09 to 0·13) compared with other studies, although estimates of repeatability (around 0·29 to 0·33) were similar to results from the literature, indicating that the accuracy of estimated breeding values in this crossbred herd was reduced because of the non-additive genetic effects. The genetic improvement of crossbred herds is discussed.
A community survey of 1045 persons aged 70 years and over was conducted to identify cases of dementia in the cities of Canberra and Queanbeyan. Cases were identified using the Canberra Interview for the Elderly, administered by lay interviewers. When diagnostic criteria were rigidly applied, the point prevalence of dementia in the combined sample of community and institutional residents was considerably lower by ICD-10 than by DSM-III-R. Both criteria showed a similar rise in prevalence with age, and no gender difference. Agreement between the two systems had a kappa of only 0·48. ‘Probable’ cases by either criteria were identified solely from respondent-provided information in order to include persons for whom no informant was available. The point prevalence of such ‘probable’ cases was more similar for the two systems, and the kappa coefficient of agreement rose to 0·80. Analysis of the various components required for a diagnosis of dementia showed that the prevalence of all increased with age. Components involving cognitive assessment were correlated with education, but other components were not. The results of the study point to important differences between ICD-10 and DSM-III-R diagnoses of dementia.
The point prevalence of depressive disorders was estimated in a sample of persons aged 70 years and over, which included both those living in the community and those in institutional settings. Lay interviewers administered the Canberra Interview for the Elderly to the subjects and their informants. The point prevalence of depressive episodes as defined by the Draft ICD-10 diagnostic criteria was 3·3%. The rate for DSM-III-R major depressive disorder was 1·0%. The latter prevalence rate is similar to those reported elsewhere for the elderly. Evidence is accumulating that older persons may indeed have low rates for depressive disorders at the formal case level. Possible reasons for this finding are offered.
A scale for depressive symptoms, based exclusively on those specified in Draft ICD-10 and DSM-III-R, showed that the elderly do experience many depressive symptoms. Contrary to expectation, these did not increase with age. The number of depressive symptoms was correlated with neuroticism, poor physical health, disability and a history of previous depression. Attention now needs to be directed to the clinical significance of depressive symptoms below the case level in elderly persons.