Melbourne Graduate School of Education - Research Publications
Now showing items 1-12 of 1656
Measurement of jet shapes in top-quark pair events at root s=7 TeV using the ATLAS detector
A measurement of jet shapes in top-quark pair events using 1.8 fb-1 of [Formula: see text]pp collision data recorded by the ATLAS detector at the LHC is presented. Samples of top-quark pair events are selected in both the single-lepton and dilepton final states. The differential and integrated shapes of the jets initiated by bottom-quarks from the top-quark decays are compared with those of the jets originated by light-quarks from the hadronic W-boson decays [Formula: see text] in the single-lepton channel. The light-quark jets are found to have a narrower distribution of the momentum flow inside the jet area than b-quark jets.
Measurement of the inclusive jet cross-section in pp collisions at root s=2.76 TeV and comparison to the inclusive jet cross-section at root s=7 TeV using the ATLAS detector
The inclusive jet cross-section has been measured in proton-proton collisions at [Formula: see text] in a dataset corresponding to an integrated luminosity of [Formula: see text] collected with the ATLAS detector at the Large Hadron Collider in 2011. Jets are identified using the anti-k t algorithm with two radius parameters of 0.4 and 0.6. The inclusive jet double-differential cross-section is presented as a function of the jet transverse momentum pT and jet rapidity y, covering a range of 20≤pT<430 GeV and |y|<4.4. The ratio of the cross-section to the inclusive jet cross-section measurement at [Formula: see text], published by the ATLAS Collaboration, is calculated as a function of both transverse momentum and the dimensionless quantity [Formula: see text], in bins of jet rapidity. The systematic uncertainties on the ratios are significantly reduced due to the cancellation of correlated uncertainties in the two measurements. Results are compared to the prediction from next-to-leading order perturbative QCD calculations corrected for non-perturbative effects, and next-to-leading order Monte Carlo simulation. Furthermore, the ATLAS jet cross-section measurements at [Formula: see text] and [Formula: see text] are analysed within a framework of next-to-leading order perturbative QCD calculations to determine parton distribution functions of the proton, taking into account the correlations between the measurements.
Improved luminosity determination in pp collisions at root s=7 TeV using the ATLAS detector at the LHC
The luminosity calibration for the ATLAS detector at the LHC during pp collisions at [Formula: see text] in 2010 and 2011 is presented. Evaluation of the luminosity scale is performed using several luminosity-sensitive detectors, and comparisons are made of the long-term stability and accuracy of this calibration applied to the pp collisions at [Formula: see text]. A luminosity uncertainty of [Formula: see text] is obtained for the 47 pb-1 of data delivered to ATLAS in 2010, and an uncertainty of [Formula: see text] is obtained for the 5.5 fb-1 delivered in 2011.
Search for a light charged Higgs boson in the decay channel H+ -> c(s)over-bar in t(t)over-bar events using pp collisions at root s=7 TeV with the ATLAS detector
A search for a charged Higgs boson (H+) in [Formula: see text] decays is presented, where one of the top quarks decays via t→H+b, followed by H+→ two jets ([Formula: see text]). The other top quark decays to Wb, where the W boson then decays into a lepton (e/μ) and a neutrino. The data were recorded in pp collisions at [Formula: see text] by the ATLAS detector at the LHC in 2011, and correspond to an integrated luminosity of 4.7 fb-1. With no observation of a signal, 95 % confidence level (CL) upper limits are set on the decay branching ratio of top quarks to charged Higgs bosons varying between 5 % and 1 % for H+ masses between 90 GeV and 150 GeV, assuming [Formula: see text].
Measurement of k(T) splitting scales in W -> l nu events at root s=7 TeV with the ATLAS detector
A measurement of splitting scales, as defined by the kT clustering algorithm, is presented for final states containing a W boson produced in proton-proton collisions at a centre-of-mass energy of 7 TeV. The measurement is based on the full 2010 data sample corresponding to an integrated luminosity of 36 pb-1 which was collected using the ATLAS detector at the CERN Large Hadron Collider. Cluster splitting scales are measured in events containing W bosons decaying to electrons or muons. The measurement comprises the four hardest splitting scales in a kT cluster sequence of the hadronic activity accompanying the W boson, and ratios of these splitting scales. Backgrounds such as multi-jet and top-quark-pair production are subtracted and the results are corrected for detector effects. Predictions from various Monte Carlo event generators at particle level are compared to the data. Overall, reasonable agreement is found with all generators, but larger deviations between the predictions and the data are evident in the soft regions of the splitting scales.
Jet energy resolution in proton-proton collisions at root s 7 TeV recorded in 2010 with the ATLAS detector
The measurement of the jet energy resolution is presented using data recorded with the ATLAS detector in proton-proton collisions at [Formula: see text]. The sample corresponds to an integrated luminosity of 35 pb-1. Jets are reconstructed from energy deposits measured by the calorimeters and calibrated using different jet calibration schemes. The jet energy resolution is measured with two different in situ methods which are found to be in agreement within uncertainties. The total uncertainties on these measurements range from 20 % to 10 % for jets within |y|<2.8 and with transverse momenta increasing from 30 GeV to 500 GeV. Overall, the Monte Carlo simulation of the jet energy resolution agrees with the data within 10 %.
Measurement of the t(t)over-bar production cross section in the tau plus jets channel using the ATLAS detector
A measurement of the top quark pair production cross section in the final state with a hadronically decaying tau lepton and jets is presented. The analysis is based on proton-proton collision data recorded by the ATLAS experiment at the LHC, with a centre-of-mass energy of 7 TeV. The data sample corresponds to an integrated luminosity of 1.67 fb-1. The cross section is measured to be [Formula: see text] and is in agreement with other measurements and with the Standard Model prediction.
Multi-channel search for squarks and gluinos in root s=7 TeV pp collisions with the ATLAS detector at the LHC
A search for supersymmetric particles in final states with zero, one, and two leptons, with and without jets identified as originating from b-quarks, in 4.7 fb-1 of [Formula: see text]pp collisions produced by the Large Hadron Collider and recorded by the ATLAS detector is presented. The search uses a set of variables carrying information on the event kinematics transverse and parallel to the beam line that are sensitive to several topologies expected in supersymmetry. Mutually exclusive final states are defined, allowing a combination of all channels to increase the search sensitivity. No deviation from the Standard Model expectation is observed. Upper limits at 95 % confidence level on visible cross-sections for the production of new particles are extracted. Results are interpreted in the context of the constrained minimal supersymmetric extension to the Standard Model and in supersymmetry-inspired models with diverse, high-multiplicity final states.
Development and Assessment of the Personal Emotional Capital Questionnaire for Adults
(1) Background: The present study developed and evaluated a personal emotional capital questionnaire (PECQ) for adults that assessed 10 domains of personal emotional capital. (2) Method: Initially, 100 items were created and then administered to students attending Semnan University and Semnan University of Medical Sciences in Iran. Of the 700 questionnaires distributed, 527 were completed in full. Students were sampledusing the multi-stage random cluster method. Exploratory factor analyses, Cronbach's alpha, and test-retest reliability were used to evaluate the scale. (3) Results: The ten components ofthe PECQ were confirmed. Test-retest correlations after 30 days were high, as was Cronbach's alpha (0.94). Thecomponents highly correlatedwith overall emotional capital. The PECQ displayed convergent validity as it positively correlated with the Keyes's Mental Health Continuum-Short Form and students'GPAs. The PECQ displayed divergent validity as it negatively correlated with measures of depression, anxiety and stress (Depression Anxiety and Stress Scale (DASS21)). Differences in overall PECQ scores and its components were examined for several variables including gender, age, marital and employment status, academic program, and field of study. PECQ scores were not sensitive to the order of administering questionnaires. (4) Conclusion: The results suggest that the PECQ is a valid and reliable measure of personal emotional capital and supports its use in adults.
Affected Others Responsivity to Gambling Harm: An International Taxonomy of Consumer-Derived Behaviour Change Techniques
Affected others impacted by someone else's gambling utilise numerous behaviour change strategies to minimise gambling-related harm but knowledge on what these strategies are and how they are implemented is limited. This study aimed to develop a comprehensive data-driven taxonomy of the types of self-help strategies used by affected others, and to categorize these into high-level behaviour change techniques (BCTs). Two taxonomies were developed using an inductive and deductive approach which was applied to a dataset of online sources and organised into the Rubicon model of action phases. These taxonomies were family-focused (how to reduce the impact of gambling harm on families) and gambler-focused (how to support the gambler in behaviour change). In total, 329 online sources containing 3536 different strategies were identified. The family-focused classification contained 16 BCTs, and the most frequent were professional support, financial management and planned consequences. The gambler-focused classification contained 11 BCTs, and the most frequent were feedback on behaviours, professional support and financial management. The majority of family- and gambler-focused BCTs fell under the actional phase of the Rubicon model. Grounded in lived experience, the findings highlight the need for intervention and resource development that includes a wide range of specific techniques that affected others can utilise.
Protocol for the Adaptation of a Direct Observational Measure of Parent-Child Interaction for Use With 7-8-Year-Old Children
(FRONTIERS MEDIA SA, 2021-01-14)
Objective: Parenting sensitivity and mutual parent-child attunement are key features of environments that support children's learning and development. To-date, observational measures of these constructs have focused on children aged 2-6 years and are less relevant to the more sophisticated developmental skills of children aged 7-8 years, despite parenting being equally important at these ages. We undertook a rigorous process to adapt an existing observational measure for 7-8-year-old children and their parents. This paper aimed to: (i) describe a protocol for adapting an existing framework for rating parent-child interactions, (ii) determine variations in parents' sensitive responding and parent-child mutual attunement ('positive mutuality') by family demographics, and (iii) evaluate the psychometric properties of the newly developed measure (i.e., inter-rater reliability, construct validity). Method: Parent-child dyads completed one home visit, including a free-play observation and parent questionnaire. Dyads were provided with three toy sets: LEGO® Classic Box, Classic Jenga®, and animal cards. The Coding of Attachment-Related Parenting (CARP) was adapted for use with 7-8-year-old children, and rating procedures were streamlined for reliable use by non-clinician/student raters, producing the SCARP:7-8 Years. Trained staff rated video-recorded observations on 11 behaviors across two domains (five for parents' sensitive responding, six for parent-child positive mutuality). Results: Data were available for 596 dyads. Consistently strong inter-rater agreement on the 11 observed behaviors was achieved across the 10-week rating period (average: 87.6%, range: 71.7% to 96.7%). Average ICCs were 0.77 for sensitive responding and 0.84 for positive mutuality. These domains were found to be related but distinct constructs (r = 0.49, p < 0.001). For both domains, average ratings were strongly associated with the main toy used during the observation (p < 0.001, highest: cards, lowest: LEGO®). Adjusted multivariate linear regression models (accounting for toy choice) revealed that less sensitive responding was associated with younger parent (p = 0.04), male parent (p = 0.03), non-English speaking background (p = 0.04), and greater neighborhood disadvantage (p = 0.02). Construct validity was demonstrated using six parent-reported psychosocial and parenting measures. Conclusion: The SCARP: 7-8 Years shows promise as a reliable and valid measure of parent-child interaction in the early school years. Toy selection for direct observation should be considered carefully in research and practice settings.
Wellbeing Literacy: A Capability Model for Wellbeing Science and Practice
Wellbeing science is the scientific investigation of wellbeing, its' antecedents and consequences. Alongside growth of wellbeing science is significant interest in wellbeing interventions at individual, organizational and population levels, including measurement of national accounts of wellbeing. In this concept paper, we propose the capability model of wellbeing literacy as a new model for wellbeing science and practice. Wellbeing literacy is defined as a capability to comprehend and compose wellbeing language, across contexts, with the intention of using such language to maintain or improve the wellbeing of oneself, others or the world. Wellbeing literacy is underpinned by a capability model (i.e., what someone is able to be and do), and is based on constructivist (i.e., language shapes reality) and contextualist (i.e., words have different meanings in different contexts) epistemologies. The proposed capability model of wellbeing literacy adds to wellbeing science by providing a tangible way to assess mechanisms learned from wellbeing interventions. Moreover, it provides a framework for practitioners to understand and plan wellbeing communications. Workplaces and families as examples are discussed as relevant contexts for application of wellbeing literacy, and future directions for wellbeing literacy research are outlined.