120 resultados para Behaviour and motivation


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background:  This study investigated the relationship between parental personality patterns and internalising and externalising behaviour problems in a clinically referred sample of children (aged 4–8) and adolescents (aged 12–18).

Methods:  Data from families involved in two clinical trials in Victoria, Australia were analysed (n = 59). Families were administered the Millons Clinical Multiaxial Inventory—III (MCMI-III) which reports personality patterns consistent with Axis II disorder and an Achenbach measure of mental health as appropriate to child's age (Child Behavior Checklist (CBCL), Youth Self-Report (YSR), or Adult Self-Report (ASR)). Relationships between internalising and externalising behaviour problems, and parental personality patterns were examined via correlation and regression analyses.

Results:  The study found a positive correlation between parental borderline, paranoid, and avoidant personality patterns, and child and adolescent externalising behaviour problems. The relationships were generally stronger for adolescents than for children. However, no relationship was observed between parental personality patterns and internalising behaviour problems.

Conclusions:  These findings underline the importance of clinical assessment of the family ecology as a whole—including the interaction between parental personality patterns and child and adolescent behaviour and emotional problems. These findings contribute to the understanding of developmental risk factors for child and adolescent mental health and the transmission of psychopathology across generations.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The microstructures, mechanical properties, corrosion behaviour and biocompatibility of the Mg-Zr-Ca alloys have been investigated for potential use in orthopaedic applications. The microstructures of the alloys were examined using X-ray diffraction analysis, optical microscopy and scanning electron microscopy. The mechanical properties of Mg-Zr-Ca alloys were determined from compressive tests. The corrosion behaviour has been investigated using an immersion test and electrochemical measurement. The biocompatibility was evaluated by cell growth factor using osteoblast-like SaOS2 cell. The experimental results indicate that the hot-rolled Mg-Zr-Ca alloys exhibit much finer microstructures than the as-cast Mg-Zr-Ca alloys which show coarse microstructures. The compressive strength of the hot-rolled alloys is much higher than that of the as-cast alloys and the human bone, which would offer appropriate mechanical properties for orthopaedic applications. The corrosion resistance of the alloys can be enhanced significantly by hot-rolling process. Hot-rolled Mg-0.5Zr-1Ca alloy (wt %) exhibits the lowest corrosion rate among all alloys studied in this paper. The hot-rolled Mg-0.5Zr-1Ca and Mg-1Zr-1Ca alloys exhibit better biocompatibility than other studied alloys and possess advanced mechanical properties, corrosion resistance and biocompatibility, suggesting that they have a great potential to be good candidates for orthopaedic applications. © 2012 Springer Science+Business Media New York.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objective
Estimate the prevalence of sexual behaviour and alcohol use and examine the association between excessive alcohol use and risky sexual behaviour in late secondary students in Victoria, Australia.

Method
The sample of Year 11 students from government and independent schools participating in the 2008 International Youth Development Study (n=450) was representative of the Victorian school population. Logistic regression analyses examined the associations between sexual behaviour, binge and compulsive drinking, adjusting for socio-demographic, school and family factors.

Results
Under half (44%) the students had experienced sex in the past year, half (50%) had engaged in binge drinking in the past two weeks and 26% reported compulsive drinking in the past year. Of those who reported sex in the past year (n=197), 34% had sex without a condom at the last sexual encounter and 28% later regretted sex due to alcohol. The likelihood of experiencing sex was increased by binge (OR=2.44, 95%CI 1.44-4.12) and compulsive drinking (OR=2.15, 95%CI 1.29-3.60). For those sexually active, binge drinking increased the risk of having three or more sexual partners (OR=3.37, 95%CI 1.11-10.26) and compulsive drinking increased the likelihood of regretted sex due to alcohol (OR=4.43, 95%CI 2.10-9.31). Excessive drinking was not associated with condom non-use.

Conclusion and implications

Risky sex – multiple sexual partners and regretted sex due to alcohol – and excessive drinking are highly prevalent and co-associated among Victorian late secondary students.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background/Objectives:Existing theoretical frameworks suggest that healthy eating is facilitated by an individual's ability, motivation and environmental opportunities. It is plausible, although largely untested, that the importance of factors related to ability and motivation differ under varied environmental conditions. This study aimed to determine whether the magnitude of associations between fruit and vegetable consumption and intrapersonal factors (ability and motivation) were modified by differences in access to stores selling these items (environmental opportunities).Subjects/Methods: Cross-sectional analysis of 4335 women from socioeconomically disadvantaged neighbourhoods in the state of Victoria, Australia. Self-reported fruit and vegetable consumption was assessed against a number of ability- and motivation-related factors. To examine whether associations were modified by store access, interactions with access to supermarkets and greengrocers within 2 km of participants' households were tested.Results:Of the two factors related to ability and seven factors related to motivation, almost all were associated with fruit and vegetable consumption. In general, associations were not modified by store access suggesting that these factors were not tempered by environmental opportunities.Conclusions:This study provides little support for the hypothesis that the importance of intra-personal factors to fruit and vegetable consumption is modified by food store access. Further research on this topic is required to inform behaviour change interventions.European Journal of Clinical Nutrition advance online publication, 21 January 2015; doi:10.1038/ejcn.2014.287.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

High-Mn Twinning Induced Plasticity (TWIP) steels have superior mechanical properties, which make them promising materials in automotive industry to improve the passenger safety and the fuel consumption. The TWIP steels are characterized by high work hardening rates due to continuous mechanical twin formation during the deformation. Mechanical twinning is a unique deformation mode, which is highly governed by the stacking fault energy (SFE). The composition of steel alloy was Fe-18Mn-0.6C-1Al (wt.%) with SFE of about 25-30 mJ/m2 at room temperature. The SFE ensures the mechanical twinning to be the main deformation mechanism at room temperature. The microstructure, mechanical properties, work hardening behaviour and SFE of the steel was studied at the temperature range of ambient ≤T[°C]≤ 400°C. The mechanical properties were determined using Instron tensile testing machine with 30kN load cell and strain rate of 10-3s-1 and the work hardening behaviour curves were generated using true stress and true strain data. The microstructure after deformation at different temperatures was examined using Zeiss Supra 55VP SEM. It was found that an increase in the deformation temperature raised the SFE resulting in the deterioration of the mechanical twinning that led to decrease not only in the strength but also in the total strain of the steel. A correlation between the temperature, the SFE, the mechanical twinning, the mechanical properties and the work hardening rate was also found. © (2014) Trans Tech Publications, Switzerland.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

1.The evolutionary causes of consistent individual differences in behavior are currently a source of debate. A recent hypothesis suggests that consistent individual differences in life-history productivity (growth and/or fecundity) may covary with behavioral traits that contribute to growth-mortality trade-offs, such as risk-proneness (boldness) and foraging activity (voraciousness). It remains unclear, however, to what extent individual behavioral and life-history profiles are set early in life, or are a more flexible result of specific environmental or developmental contexts that allow bold and active individuals to acquire more resources. 2.Longitudinal studies of individually housed animals under controlled conditions can shed light on this question. Since growth and behaviour can both vary within individuals (they are labile), studying between-individual correlations in behaviour and growth rate requires repeated scoring for both variables over an extended period of time. However, such a study has not yet been done. 3.Here, we repeatedly measured individual mass 7-times each, boldness 40-times each, and voracity 8-times each during the first four months of life on 90 individually-housed crayfish (Cherax destructor). Animals were fed ad-libitum, generating a context where individuals can express their intrinsic growth rate (i.e. growth capacity), but in which bold and voracious behaviour is not necessary for high resource acquisition (crayfish can and do hoard food back to their burrow). 4.We show that individuals that were consistently bold over time during the day were also bolder at night, were more voracious, and maintained higher growth rates over time than shy individuals. Independent of individual differences, we also observed that males were faster growing, bolder, and more voracious than females. 5.Our findings imply that associations between bold behaviour and fast growth can occur in unlimited food contexts where there is no necessary link between bold behaviour and resource acquisition - offering support for the 'personality- productivity' hypothesis. We suggest future research should study links between consistent individual differences in behaviour and life-history under a wider range of contexts, in order to shed light on the role of biotic and abiotic conditions in the strength, direction and stability of their covariance. This article is protected by copyright. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

BACKGROUND: There is little empirical evidence of the impact of transition from primary to secondary school on obesity-related risk behaviour. The purpose of this study was to examine the effect of a change of school system on physical activity (PA) and sedentary behaviour in pre-early adolescents. METHODS: Fifteen schools in Victoria, Australia were recruited at random from the bottom two strata of a five level socio-economic scale. In nine schools, students in year 6 primary school transitioned to a different school for year 7 secondary school, while in six schools (combined primary-secondary), students remained in the same school environment from year 6 to year 7. Time 1 (T1) measures were collected from students (N=245) in year 6 (age 11-13). Time 2 (T2) data were collected from 243 (99%) of the original student cohort when in year 7. PA and sedentary behaviour data were collected objectively (via ActiGraph accelerometer) and subjectively (via child self-report recall questionnaire). School environment data were collected via school staff survey. Change of behaviour analyses were conducted longitudinally i) for all students and ii) by change/no change of school. Mixed model regression analysis tested for behavioural interaction effects of changing/not changing school. RESULTS: Sixty-three percent (N=152) changed schools from T1 to T2. Across all students we observed declines in average daily moderate to vigorous physical activity (MVPA) (-4 min) and light PA (-23 min), and increases in average daily sedentary behaviour (16 min), weekday leisure screen time (17 min) and weekday homework screen time (25 min), all P<0.05. Compared to students who remained in the same school environment, students who changed school reported a greater reduction in PA intensity at recess and lunch, less likelihood to cycle to/from school, greater increase in weekday (41 mins) and weekend (45 mins) leisure screen time (P<0.05) and greater encouragement to participate in sport. School staff surveys identified that sport participation encouragement was greater in primary and combined primary-secondary than secondary schools (P<0.05). CONCLUSION: Transitioning from primary to secondary school negatively impacts on children's PA and sedentary behaviour, and has further compounding effects on behaviour type by changing school environments.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

BACKGROUND: What study participants think about the nature of a study has been hypothesised to affect subsequent behaviour and to potentially bias study findings. In this trial we examine the impact of awareness of study design and allocation on participant drinking behaviour. METHODS/DESIGN: A three-arm parallel group randomised controlled trial design will be used. All recruitment, screening, randomisation, and follow-up will be conducted on-line among university students. Participants who indicate a hazardous level of alcohol consumption will be randomly assigned to one of three groups. Group A will be informed their drinking will be assessed at baseline and again in one month (as in a cohort study design). Group B will be told the study is an intervention trial and they are in the control group. Group C will be told the study is an intervention trial and they are in the intervention group. All will receive exactly the same brief educational material to read. After one month, alcohol intake for the past 4 weeks will be assessed. DISCUSSION: The experimental manipulations address subtle and previously unexplored ways in which participant behaviour may be unwittingly influenced by standard practice in trials. Given the necessity of relying on self-reported outcome, it will not be possible to distinguish true behaviour change from reporting artefact. This does not matter in the present study, as any effects of awareness of study design or allocation involve bias that is not well understood. There has been little research on awareness effects, and our outcomes will provide an indication of the possible value of further studies of this type and inform hypothesis generation. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12610000846022.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The low cycle fatigue (LCF) behaviour of a dual phase (DP) steel with different martensite volume fractions has been investigated, with particular focus on fatigue life, cyclic hardening/softening behaviour and microstructural evolution. DP steels with martensite volume fractions between 13% and 88% were produced and their monotonic and cyclic deformation behaviours evaluated. The LCF life has been examined in depth and compared with published literature. It has been concluded that, once normalised for plastic strain amplitude, the fatigue life was found to be significantly reduced by an increase in the martensite volume fraction. All alloys were observed to show some initial cyclic hardening followed by cyclic softening. Clear sub-cell formation occurred in ferrite grains irrespective of the martensite volume fraction, and it is suggested that this cell formation and martensite softening are responsible for the cyclic softening behaviour.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Abstract Background. Heavy episodic drinking (HED) has been associated with increased risk for short- and long-term injury and harms, such as violence and delinquent behaviour; however, the temporal relationship between the two remains unclear, pathways between HED and delinquent behaviour from adolescence to emerging adulthood. Methods. Data were drawn from the Australian Temperament Project; a population-based longitudinal study that has followed the health and development of participants (and parents) across 30 years from birth in 1982.The analytic sample was 1650 participants and included five measurement waves spanning adolescence (3 waves: 13–18 years) and young adulthood (2 waves; 19–24 years). Results. There was strong continuity across waves of both HED and delinquency, as well as across-time associations between them. Delinquent behaviour in adolescence was associated with up to twofold increases in the odds of HED at each subsequent adolescent wave. HED in the late teens was associated with over fourfold increases in the odds of persistent (two waves) HED in young adulthood. HED in the late teens was associated with increases in the odds of delinquent behaviour in young adulthood (over twofold for male and one and a half-fold for female participants). Conclusions. While delinquent behaviour predicts both future HED and future delinquent behaviour in adolescence, once young people reach the legal drinking age of 18 years, HED becomes a predictor of current and future delinquent behaviour and future HED, suggesting that increased access to alcohol increases the likelihood of young people engaging in delinquent behaviour. [Miller PG, Butler E, Richardson B, Staiger PK, Youssef GJ, Macdonald JA, Sanson A, Edwards B, Olsson CA. Relationships between problematic alcohol consumption and delinquent behaviour from adolescence to young adulthood. Drug Alcohol Rev 2015]

Relevância:

100.00% 100.00%

Publicador:

Resumo:

UNLABELLED: Regular physical activity and limiting extended periods of sitting are two behaviours critical for the prevention of obesity in young people. The purpose of the systematic review was to synthesize the psychometric evidence for self-report use-of-time tools that assess these behaviours. Articles were retrieved that reported reliability and/or validity for use-of-time tools in participants aged 18 years or under. Outcome variables were physical activity, sedentary behaviour and energy expenditure. Study quality was appraised, and the results summarized narratively. Sixteen studies and six different tools were identified. The tools were the Previous Day Physical Activity Recall, the Three-Day Physical Activity Recall, the Physical Activity Interview, the Computerized Activity Recall, the Activitygram, and the Multimedia Activity Recall for Children and Adolescents. Overall, tools indicated moderate validity compared with objective and criterion comparison methods. Generally, validity correlation coefficients were in the range of 0.30-0.40. Correlation coefficients for test-retest reliability ranged widely from 0.24 to 0.98. CONCLUSION: Use-of-time tools have indicated moderate reliability and validity for the assessment of physical activity and energy expenditure. Future research should focus on using criterion methods and on validating specifically for sedentary behaviour outcomes. Implementation of these tools for population surveillance should be considered.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

RATIONALE: Smoking cessation is associated with cigarette cravings and tobacco withdrawal symptoms (TWS), and exercise appears to ameliorate many of these negative effects. A number of studies have examined the relationships between exercise, cigarette cravings, and TWS. OBJECTIVES: The objectives of this study were (a) to review and update the literature examining the effects of short bouts of exercise on cigarette cravings, TWS, affect, and smoking behaviour and (b) to conduct meta-analyses of the effect of exercise on cigarette cravings. METHODS: A systematic review of all studies published between January 2006 and June 2011 was conducted. RESULTS: Fifteen new studies were identified, 12 of which found a positive effect of exercise on cigarette cravings. The magnitude of statistically significant effect sizes for 'desire to smoke' and 'strength of desire to smoke' ranged from 0.4 to 1.98 in favour of exercise compared to passive control conditions, and peaked either during or soon after treatment. Effects were found up to 30 min post-exercise. Cigarette cravings were reduced following exercise with a wide range of intensities from isometric exercise and yoga to activity as high as 80-85 % heart rate reserve. Meta-analyses revealed weighted mean differences of -1.90 and -2.41 in 'desire to smoke' and 'strength of desire to smoke' outcomes, respectively. Measures of TWS and negative affect were reduced following light-moderate intensity exercise, but increased during vigorous exercise. CONCLUSIONS: Exercise can have a positive effect on cigarette cravings and TWS. However, the most effective exercise intensity to reduce cravings and the underlying mechanisms associated with this effect remain unclear.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

AIM: We aim to describe health service (HS) use in the first 6 months post-partum and to examine the associations between service costs, infant behaviour and maternal depressive symptoms. METHODS: Participants were 781 infants and mothers in Melbourne, Australia. Mothers reported infant feeding, sleeping and crying problems, depressive symptoms and health service use. Costs were valued in 2012 Australian dollars. RESULTS: The most common services used were maternal child health nurses, general practitioners (GP) and allied health. Infant feeding problems were associated with increased costs for services relevant to infant behaviour including maternal child health nurses (P = 0.007), GP (P = 0.008) and paediatricians (P = 0.03). Maternal depressive symptoms were associated with increased costs for services relevant to depressive symptoms including parenting centres (P = 0.04), GP (P = 0.004), psychiatrists (P = 0.02) and psychologists (P = 0.001). Mothers who completed high school had higher service costs for infant problems than those with lower education (P = 0.02). Single mothers had higher costs for services used for their depressive symptoms than partnered mothers (P < 0.001). Mothers with English as a second language had lower service costs for their depressive symptoms (P = 0.02). CONCLUSIONS: Infant feeding problems and maternal depressive symptoms are associated with higher costs for health services relevant to these conditions. Cost-effective strategies to manage these conditions are needed with accessibility being ensured for mothers who are experiencing social adversity.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objective: This study used matched samples from schools in the states of Victoria and Washington to compare sexual behaviour in early adolescence. It was hypothesised that the contrasting dominant policy objectives of harm minimisation in Australia and abstinence in the USA would result in state differences for markers of sexual risk, mirroring prior cross-national findings in substance use. Method: A two-stage cluster sampling approach was used to recruit students from the two states. Self-reported sexual behaviour was examined for 1,596 students in annual surveys from Grade 7 in 2002 to Grade 9 in 2004. Prevalence estimates were derived for each measure of sexual behaviour, and comparisons were made between gender groups in each state. Results: State differences were found for girls' first sex, with significantly more girls in Washington than Victoria having had sex by Grade 7. By Grade 9, significantly more girls in Victoria reported sex in the last year and more sexual partners than girls in Washington. A large proportion of Grade 9 students across both states reported inconsistent contraception use. Conclusions: Contradicting the abstinence policy objective, first sex by Grade 7 was more prevalent in Washington than in Victoria. While sexual behaviour was more prevalent in Grade 9 in Victoria, the sexually active showed no clear cross-national differences in markers of risk such as contraception use and pregnancy outcomes. Findings demonstrate few cross-national differences in adolescent sexual behaviour despite the different policy contexts of Victoria and Washington.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

BACKGROUND: Office workers spend a large proportion of their working hours sitting. This may contribute to an increased risk of chronic disease and premature mortality. While there is growing interest in workplace interventions targeting prolonged sitting, few qualitative studies have explored workers' perceptions of reducing occupational sitting outside of an intervention context. This study explored barriers to reducing office workplace sitting, and the feasibility and acceptability of strategies targeting prolonged sitting in this context.

METHODS: Semi-structured interviews were conducted with a convenience sample of 20 office workers (50 % women), including employees and managers, in Melbourne, Australia. The three organisations (two large, and one small organisation) were from retail, health and IT industries and had not implemented any formalised approaches to sitting reduction. Questions covered barriers to reducing sitting, the feasibility of potential strategies aimed at reducing sitting, and perceived effects on productivity. Interviews were audiotaped and transcribed verbatim. Data were analysed using thematic analysis.

RESULTS: Participants reported spending most (median: 7.2 h) of their working hours sitting. The nature of computer-based work and exposure to furniture designed for a seated posture were considered to be the main factors influencing sitting time. Low cost strategies, such as standing meetings and in-person communication, were identified as feasible ways to reduce sitting time and were also perceived to have potential productivity benefits. However, social norms around appropriate workplace behaviour and workload pressures were perceived to be barriers to uptake of these strategies. The cost implications of height-adjustable workstations influenced perceptions of feasibility. Managers noted the need for an evidence-based business case supporting action on prolonged sitting, particularly in the context of limited resources and competing workplace health priorities.

CONCLUSIONS: While a number of low-cost approaches to reduce workplace sitting are perceived to be feasible and acceptable in the office workplace, factors such as work demands and the organisational social context may still act as barriers to greater uptake. Building a supportive organisational culture and raising awareness of the adverse health effects of prolonged sitting may be important for improving individual-level and organisational-level motivation for change.