9 resultados para harmonic oscillator elementary review classical quantum

em Deakin Research Online - Australia


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This article reviews three classics of polyamory, Anapol's Love Without Limits: The Quest for Sustainable Intimate Relationships; Easton and Liszt's The Ethical Slut; and Nearing's Loving More: The Polyfidelity Primer. The reviewer defines the authors as pioneering poly women who have mapped the territory for authentic alternatives to compulsory monogamy in realistic yet visionary ways.

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There is increasing evidence that children display high levels of weight and muscle concerns, which include body dissatisfaction and problem eating. In order to address these issues, researchers have designed and implemented prevention programs for this age group. Thirteen published studies were located and reviewed, with children aged 8–12 years from elementary schools, or equivalent. Overall, the programs were shown to be effective in improving children's knowledge at post-test and at follow-up assessments. However, there is limited evidence to show that the programs reduced or prevented body image concerns and/or problem eating. Too few studies have examined muscle concerns so no conclusions can yet be drawn about this domain. Limitations of the studies and suggestions for future prevention efforts are discussed.

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Objective: To determine whether nutrition interventions widen dietary inequalities across socioeconomic status groups.

Design: Systematic review of interventions that aim to promote healthy eating.

Data sources: CINAHL and MEDLINE were searched between 1990 and 2007.

Review methods: Studies were included if they were randomised controlled trials or concurrent controlled trials of interventions to promote healthy eating delivered at a group level to low socioeconomic status groups or studies where it was possible to disaggregate data by socioeconomic status.

Results: Six studies met the inclusion criteria. Four were set in educational setting (three elementary schools, one vocational training). The first found greater increases in fruit and vegetable consumption in children from high-income families after 1 year (mean difference 2.4 portions per day, p<0.0001) than in children in low-income families (mean difference 1.3 portions per day, p<0.0003). The second did not report effect sizes but reported the nutrition intervention to be less effective in disadvantaged areas (p<0.01). The third found that 24-h fruit juice and vegetable consumption increased more in children born outside the Netherlands ("non-native") after a nutrition intervention (beta coefficient = 1.30, p<0.01) than in "native" children (beta coefficient = 0.24, p<0.05). The vocational training study found that the group with better educated participants achieved 34% of dietary goals compared with the group who had more non-US born and non-English speakers, which achieved 60% of dietary goals. Two studies were conducted in primary care settings. The first found that, as a result of the intervention, the difference in consumption of added fat between the intervention and the control group was –8.9 g/day for blacks and –12.0 g/day for whites (p<0.05). In the second study, there was greater attrition among the ethnic minority participants than among the white participants (p<0.04).

Conclusions: Nutrition interventions have differential effects by socioeconomic status, although in this review we found only limited evidence that nutrition interventions widen dietary inequalities. Due to small numbers of included studies, the possibility that nutrition interventions widen inequalities cannot be excluded. This needs to be considered when formulating public health policy.

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The primary aim of this review was to identify and evaluate the strength of associations of the key parental factors measured in studies examining early childhood physical activity (PA). A systematic review of the literature, using databases PsychINFO, Medline, Academic Search Complete, PSYCHinfo, and CINHAL, published between January 1986 and March 2011 was conducted; 20 papers were relevant for the current review. While 12 parenting variables were identified, only 5 of these had been investigated sufficiently to provide conclusive findings. There were inconsistencies in the findings involving the social learning variable parental enjoyment and variables involving parental behaviours such as maternal depression and self-efficacy, and rules for sedentary behaviour, and parental perceptions, which included perceived importance of PA, fear of safety, and perception of child’s motor competence. Given these inconsistencies, a metaanalysis was conducted to determine whether the method of measuring PA (objective or subjective) influenced the strength of associations between the parental factors and young children’s PA. There was no difference in the strength of associations in the studies that used objective or subjective measurement (via parent self-report). Further investigation is needed to clarify and understand the specific parental influences and behaviours that are associated with PA in young children. In particular, longitudinal research is needed to better understand how parental influences and PA levels of children during the formative preschool and early elementary school years are associated.

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BACKGROUND
Fundamental movement skill (FMS) proficiency is positively associated with physical activity and fitness levels. The objective of this study was to systematically review evidence for the benefits of FMS interventions targeting youth.

METHODS
A search with no date restrictions was conducted across 7 databases. Studies included any school-, home-, or community-based intervention for typically developing youth with clear intent to improve FMS proficiency and that reported statistical analysis of FMS competence at both preintervention and at least 1 other postintervention time point. Study designs included randomized controlled trials (RCTs) using experimental and quasi-experimental designs and single group pre-post trials. Risk of bias was independently assessed by 2 reviewers.

RESULTS
Twenty-two articles (6 RCTs, 13 quasi-experimental trials, 3 pre-post trials) describing 19 interventions were included. All but 1 intervention were evaluated in primary/elementary schools. All studies reported significant intervention effects for ≥1 FMS. Meta-analyses revealed large effect sizes for overall gross motor proficiency (standardized mean difference [SMD] = 1.42, 95% confidence interval [CI] 0.68–2.16, Z = 3.77, P < .0002) and locomotor skill competency (SMD = 1.42, 95% CI 0.56–2.27, Z = 3.25, P = .001). A medium effect size for object control skill competency was observed (SMD = 0.63, 95% CI 0.28–0.98, Z = 3.53, P = .0004). Many studies scored poorly for risk of bias items.

CONCLUSIONS
School- and community-based programs that include developmentally appropriate FMS learning experiences delivered by physical education specialists or highly trained classroom teachers significantly improve FMS proficiency in youth.

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Background Previous research has shown that those employed in certain occupations, such as doctors and farmers, have an elevated risk of suicide, yet little research has sought to synthesise these findings across working-age populations. Aims To summarise published research in this area through systematic review and meta-analysis. Method Random effects meta-analyses were used to calculate a pooled risk of suicide across occupational skill-level groups. Results Thirty-four studies were included in the meta-analysis. Elementary professions (e.g. labourers and cleaners) were at elevated risk compared with the working-age population (rate ratio (RR) = 1.84, 95% CI 1.46-2.33), followed by machine operators and deck crew (RR = 1.78, 95% CI 1.22-2.60) and agricultural workers (RR = 1.64, 95% CI 1.19-2.28). Results suggested a stepwise gradient in risk, with the lowest skilled occupations being at greater risk of suicide than the highest skill-level group. Conclusions This is the first comprehensive meta-analytical review of suicide and occupation. There is a need for future studies to investigate explanations for the observed skill-level differences, particularly in people employed in lower skill-level groups.

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In this paper, a review on condition monitoring of induction motors is first presented. Then, an ensemble of hybrid intelligent models that is useful for condition monitoring of induction motors is proposed. The review covers two parts, i.e.; (i) a total of nine commonly used condition monitoring methods of induction motors; and (ii) intelligent learning models for condition monitoring of induction motors subject to single and multiple input signals. Based on the review findings, the Motor Current Signature Analysis (MCSA) method is selected for this study owing to its online, non-invasive properties and its requirement of only single input source; therefore leading to a cost-effective condition monitoring method. A hybrid intelligent model that consists of the Fuzzy Min-Max (FMM) neural network and the Random Forest (RF) model comprising an ensemble of Classification and Regression Trees is developed. The majority voting scheme is used to combine the predictions produced by the resulting FMM-RF ensemble (or FMM-RFE) members. A benchmark problem is first deployed to evaluate the usefulness of the FMM-RFE model. Then, the model is applied to condition monitoring of induction motors using a set of real data samples. Specifically, the stator current signals of induction motors are obtained using the MCSA method. The signals are processed to produce a set of harmonic-based features for classification using the FMM-RFE model. The experimental results show good performances in both noise-free and noisy environments. More importantly, a set of explanatory rules in the form of a decision tree can be extracted from the FMM-RFE model to justify its predictions. The outcomes ascertain the effectiveness of the proposed FMM-RFE model in undertaking condition monitoring tasks, especially for induction motors, under different environments. © 2014 Elsevier Ltd. All rights reserved.

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BACKGROUND: Obesity in early childhood is a robust predictor of obesity later in life. Schools provide unparalleled access to children and have subsequently become major intervention sites. However, empirical evidence supporting the effectiveness of school-based interventions against childhood obesity is of limited scope and unknown quality. The aim of this systematic review is to critically assess how researchers have characterized the school environment in determining its effect on childhood weight status in order to improve the quality and consistency of research in this area. We conducted a narrative review with a systematic search of the literature in line with PRISMA guidelines (2009). Original peer-reviewed research articles in English were searched from Medline, EMBASE, CENTRAL, CINAHL and PsycINFO databases from earliest record to January 2014. We included empirical research that reported at least one measure of the primary/elementary school environment and its relationship with at least one objective adiposity-related variable for students aged 4-12 years. Two authors independently extracted data on study design, school-level factors, student weight status, type of analysis and effect. RESULTS: Five studies met the inclusion criteria. Each study targeted different parts of the school environment and findings across the studies were not comparable. The instruments used to collect school-level data report no validity or reliability testing. CONCLUSIONS: Our review shows that researchers have used instruments of unknown quality to test if the school environment is a determinant of childhood obesity, which raises broader questions about the impact that schools can play in obesity prevention.