Assessing the self-heating behaviour of Callide coal using a 2-metre column

A 2-m, adiabatic column has been successfully refurbished and recommissioned for coal self-heating research at The University of Queensland. Subbituminous coal from the Callide Coalfields reached thermal runaway in just under 19 days from a starting temperature of 20-22 degreesC. The coal was loaded as two layers, with an R-70 index of 2.73 degreesC h(-1) and 5.90 degreesC h(-1) for the upper layer and lower layer respectively. Initially, a hotspot developed in the upper layer between 120 and 140 cm from the air inlet due to moisture adsorption. After 7 days, self-heating in the lower half of the column began to take over, consistent with the higher R-70 index of this coal. The location of the final hotspot was approximately 60 cm from the air inlet. Further tests on Australian coals, with the column, will enable a better understanding of coal self-heating under conditions closely resembling mining, transport and storage of coal. The results from the column will also provide industry with the information needed to manage the coal self-heating hazard. (C) 2002 Elsevier Science Ltd. All rights reserved.

Lesch-Nyhan disease in a 20-year-old man incorrectly described as developing 'cerebral palsy' after general anaesthesia in infancy

Lesch–Nyhan disease (LND) is a rare X-linked recessive genetic disorder caused by a deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT) enzyme. The classic clinical condition is characterized by cognitive impairment, hypotonia at rest, choreoathetosis, hyperuricaemia and the hallmark symptom of severe and involuntary self-mutilation. We describe a man with LND who was initially thought to have suffered from a dyskinetic cerebral palsy after an uncomplicated inguinal herniorrhaphy under general anaesthesia at 5 1/2 months of age. In the absence of overt self-injurious behaviour, the diagnosis was not considered for nearly two decades. The diagnosis of LND was established at 20 years of age through clinical review, biochemical examinations and molecular analysis. HPRT haemolysate activity was 7.6% of the normal control, suggesting that he had a milder variant of the disease. Mutation analysis of the HPRT gene revealed a novel missense mutation, c.449T > G in exon 6 (p.V150G). Cascade testing of family members revealed that the mother was heterozygous for the mutation but two siblings (a brother and a sister) did not carry the sequence mutation. Whether the onset of neurological abnormalities in this particular case can be attributed to the general anaesthesia is discussed.

Ultracentrifugal studies of the effect of molecular crowding by trimethylamine N-oxide on the self-association of muscle glycogen phosphorylase b

The suitability of sedimentation equilibrium for characterizing the self-association of muscle glycogen phosphorylase b has been reappraised. Whereas sedimentation equilibrium distributions for phosphorylase b in 40 mM Hepes buffer (pH 6.8) supplemented with 1 mM AMP signify a lack of chemical equilibrium attainment, those in buffer supplemented additionally with potassium sulfate conform with the requirements of a dimerizing system in chemical as we:ll as sedimentation equilibrium. Because the rate of attainment of chemical equilibrium under the former conditions is sufficiently slow to allow resolution of the dimeric and tetrameric enzyme species by sedimentation velocity, this procedure has been used to examine the effects of thermodynamic nonideality arising from molecular crowding try trimethylamine N-oxide on the self-association behaviour of phosphorylase b. In those terms the marginally enhanced extent of phosphorylase b self-association observed in the presence of high concentrations of the cosolute is taken to imply that the effects of thermodynamic nonideality on the dimer-tetramer equilibrium are being countered by those displacing the T reversible arrow R isomerization equilibrium for dimer towards the smaller, nonassociating T state. Because the R state is the enzymically active form, an inhibitory effect is the predicted consequence of molecular crowding by high concentrations of unrelated solutes. Thermodynamic nonideality thus provides an alternative explanation for the inhibitory effects of high concentrations of glycerol, sucrose and ethylene glycol on phosphorylase b activity, phenomena that have been attributed to extremely weak interaction of these cryoprotectants with the T state of the enzyme.

Considerations in the design of a mixed-method cluster evaluation of a community programme for 'at-risk' young people

This article discusses the design of a comprehensive evaluation of a community development programme for young people 'at-risk' of self-harming behaviour. It outlines considerations in the design of the evaluation and focuses on the complexities and difficulties associated with the evaluation of a community development programme. The challenge was to fulfil the needs of the funding body for a broad, outcome-focused evaluation while remaining close enough to the programme to accurately represent its activities and potential effects at a community level. Specifically, the strengths and limitations of a mixed-method evaluation plan are discussed with recommendations for future evaluation practice.

The clinical effectiveness of a multisensory therapy on clients with developmental disability

Many clients in Hong Kong with developmental disabilities stay in mental hospitals because of mental disorders and behavioural problems. There is a need to identify strategies that promote psychological well-being and reduce problem behaviours in this group of clients. This study evaluates the impact of multisensory therapy on participants’ emotional state, level of relaxation, challenging behaviour, stereotypic self-stimulating behaviour (SSB) and adaptive behaviour (AB). Using an experimental design, 89 participants were recruited from a developmental disability unit in a hospital in Hong Kong and randomly assigned to either an experimental (n = 48) or a control group (n = 41). Multisensory therapy sessions (n = 36) were conducted with experimental group and activity sessions (n = 36) were conducted with controls for 12 weeks. Multisensory therapy promoted participants’ positive emotions and relaxation. However, there was no evidence that multisensory therapy was superior to activity therapy in reducing aggressive behaviour and stereotypic self-stimulating behaviour or promoting adaptive behaviour. The key variables that influence clients’ behaviours in the multisensory therapy may be related to the relationship with the carer, constant environment, relaxation and freedom from demands rather than sensory input. Multisensory therapy could be used to provide leisure and promote psychological well-being, rather than for reducing problem behaviour.

Self-reported risk perception, mood and risk behaviour across the human menstrual cycle

Normally ovulating women exhibit a decline in risk behaviours that may lead to sexual assault during the fertile phase of the menstrual cycle, whereas women using the Pill do not. The current study tests two explanatory models: the mood and fertility models. Self-reported risk and non-risk behaviours, mood, and risk perception in sexual assault and physical risk domains were assessed by testing fiftyone women at menstruation and during their fertile period. Based on the decline in risk behaviours shown in past research, the fertility model predicts that normally ovulating women will display greater risk perception during the fertile phase of their cycle. The mood model predicts that at menstruation, when negative mood is highest, risk perception will be increased and risk behaviours correspondingly reduced. Risk behaviours did not vary over the cycle or between groups. Overall, results support the mood model. Negative mood was greater at menstruation and positive mood during the fertile period for both groups, rational risk perception was correspondingly greater at menstruation. The fertility model was not supported as risk perception ratings did not vary in the expected direction and ratings were not specific to the sexual assault domain.

Women drivers' behaviour, socio-demographic characteristics and accidents

The purpose of this study was to examine factors which affect driving behaviour and accident rates in women in Australia. Two groups of women (aged 18-23 and 45-50 years) participating in the Australian Longitudinal Study on Women's Health, completed a mailed questionnaire on driver behaviour and road accidents. Self reported accident rates in the last 3 years were 1.87 per 100 000 km for the young drivers (n = 1199) and 0.59 per 100 000 km for the mid-age drivers (n = 1564); most accidents involved damage only, not injury. Mean scores for lapses obtained using the Driver Behaviour Questionnaire, were similar in the two age groups and similar to those found in other studies. In contrast, scores for errors and violations for the young women were higher than for the mid-age group and previous reports using the same instruments. Riskier driving behaviour among young women was associated with stress and habitual alcohol consumption. In the mid-age group, poorer driver behaviour scores were related to higher levels of education, feeling rushed, higher habitual alcohol consumption and lower life satisfaction scores. Accident rates in both groups were significantly related to lapses. Women born in non-English speaking countries had significantly higher risk of accidents compared to Australian-born women: relative risk = 3.40, 95% confidence interval (1.93, 5.98) for the young drivers; relative risk = 1.77, 95% confidence interval (1.11, 2.83) for mid-age drivers. These findings support the need for road safety campaigns targeted at young women to reduce dangerous driving practices, such as speeding,'tail gating' and overtaking on the inside. There is also a need for further research to understand how lifestyle characteristics are associated with higher risk of accidents and to explore factors which might account for the higher risk for women drivers who were born overseas. (C) 1999 Elsevier Science Ltd. All rights reserved.

Self-Directed Behavioral Family Intervention for Parents of Oppositional Children in Rural and Remote Areas

Twenty-four parents of oppositional preschoolers were randomly assigned to either a self-directed behavioral family intervention condition (SD) or to a waitlist control group (WL). The self-directed parent training program based on self-regulation principles, consisted of a written information package and weekly telephone consultations for 10 weeks. At posttest, in comparison to the WL group, children in the SD group had lower levels of behavior problems on parent report measures of child behavior. At posttreatment, parents in the SD condition reported increased levels of parenting competence and lower levels of dysfunctional parenting practices as compared to parents in the WL condition. In addition, mothers reported lower levels of anxiety, depression, and stress as compared to mothers in the WL condition at posttreatment. Using mother's reports, gains in child behavior and parenting practices achieved at posttreatment were maintained at 4-month follow-up.

The investigation of factors underlying deficits in self-awareness and self-regulation

Primary objective: To examine a theoretical model which suggests that a contribution of both psychological and neuropsychological factors underlie deficits in self-awareness and self-regulation. Research design: Multivariate design including correlations and analysis of variance (ANOVA). Methods: Sixty-one subjects with acquired brain injury (ABI) were administered standardized measures of self-awareness and self-regulation. Psychological factors included measures of coping-related denial, personality-related denial and personality change. Neuropsychological factors included an estimate of IQ and two measures of executive functioning that assess capacity for volition and purposive behaviour. Main outcomes and results: The findings indicated that the relative contribution of neuropsychological factors to an outcome of deficits in self-awareness and self-regulation had a more direct effect than psychological factors. In general, measures of executive functioning had a direct relationship, while measures of coping-related and personality-related denial had an indirect relationship with measures of self-awareness and self-regulation. Conclusion: The findings highlighted the importance of measuring both neuropsychological and psychological factors and demonstrated that the relative contribution of these variables varies according to different levels of self-awareness and self-regulation.

The differential role of alcohol expectancies, drinking refusal self-efficacy and coping resources in predicting alcohol consumption in community and clinical samples

This study explored the relationship between coping, alcohol expectancies and drinking refusal self-efficacy in predicting drinking behaviour in both community and clinical samples. These variables were found to have differential effects in their association with frequency and volume of alcohol consumption across the two samples. Generally, drinking refusal self-efficacy was a more salient factor in relation to frequency and volume of community drinking, while coping and expectancies were more strongly associated with frequency of drinking sessions by problem drinkers. The interaction between expectancies and drinking refusal self-efficacy was related to volume of consumption in both groups, while coping and expectancies interacted in their association with frequency in the clinical group. The findings are discussed with regard to the different patterns of cognitive variables governing the decision to drink and the amount consumed in each drinking session, which may differentiate community and problem drinkers.

Kinetic parameters associated with self-heating of New Zealand coals under adiabatic conditions

Adiabatic self-heating tests were carried out on five New Zealand coal samples ranging in rank from lignite to high-volatile bituminous. Kinetic parameters of oxidation were obtained front the self-heating curves assuming Arrhenius behaviour. The activation energy E (kJ mol(-1)) and the pre-exponential factor A (s(-1)) were determined in the temperature range of 70-140 degreesC. The activation energy exhibited a definite rank relationship with a minimum E of 55 kJ mol(-1) occurring at a Suggate rank of similar to6.2 corresponding to subbituminous C. Either side of this rank there was a noticeable increase in the activation energy indicating lower reactivity of the coal. A similar rank trend was also observed in the R-70 self-heating rate index values that were taken from the initial portion of the self-heating curve front 40 to 70 degreesC. From these results it is clear that the adiabatic method is capable of providing reliable kinetic parameters of coal oxidation.

Social approval and trait self-esteem

Interpersonal theories of self-esteem that tie self-esteem to perceptions of ones acceptability to other people suggest that self-evaluations should predict global self-esteem to the degree to which an individual believes that a particular attribute is important for social approval. In the present study, participants completed a measure of global self-esteem, rated themselves in five domains, and indicated how important those domains were for approval or disapproval. The results showed that, in four of five domains, the interaction between self-evaluations and the perceived approval-value of that domain aided in the prediction of global self-esteem. Generally, for participants who rated themselves positively in a domain, those who believed that the domain was important in affecting social approval or disapproval had higher self-esteem than those who did not believe it would influence acceptability.

Sexual abuse, antisocial behaviour and substance use: gender differences in young community adolescents

Objective: To investigate gender-specific relationships between self-reported sexual abuse, antisocial behaviour and substance use in a large community sample of adolescents. Method: A cross-sectional study of students aged, on average, 13 (n = 2596), 14 (n = 2475) and 15 years (n = 2290), from 27 schools in South Australia with a questionnaire including sexual abuse, frequency and severity of substance use, depressive symptomatology (CES-D), family functioning (McMaster Family Assessment Device), and antisocial behaviour (an adapted 22-item Self-Report Delinquency Scale). Logistic regression analyses using HLM V5.05 with a population-average model were conducted. Results: In the model considered, reported sexual abuse is significantly independently associated with antisocial behaviour, controlling for confounding factors of depressive symptomatology and family dysfunction, with increased risks of three- to eightfold for sexually abused boys, and two- to threefold for sexually abused girls, compared to nonabused. Increased risks of extreme substance use in sexually abused girls (age 13) and boys (ages 13-15) are more than fourfold, compared to nonabused. Age differences were not statistically significant. Conclusion: Childhood sexual abuse is a risk factor for the development of antisocial behaviour and substance use in young adolescents. Clinicians should be aware of gender differences.