Positive displacement machines : Modern design innovations and tools
- Authors: Sultan, Ibrahim , Phung, Truong
- Date: 2019
- Type: Text , Book
- Relation: Positive Displacement Machines: Modern Design Innovations and Tools
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- Description: Positive Displacement Machines: Modern Design Innovations and Tools explains the design and workings of a wide range of positive displacement pumps, compressors and gas expanders. Written at a mathematical and technical level, the book explores the most influential research in this field over the past decade, along with industry best practices. Sections highlight the importance of using the latest computation techniques and discuss how to follow the proper design procedures to achieve a desired outcome. © 2020 Elsevier Inc. All rights reserved.
Effect of rock mass permeability and rock fracture leak-off coefficient on the pore water pressure distribution in a fractured slope
- Authors: Shaghaghi, Tahereh , Ghadrdan, Mohsen , Tolooiyan, Ali
- Date: 2020
- Type: Text , Journal article
- Relation: Simulation Modelling Practice and Theory Vol. 105, no. (2020), p. 1-13
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- Description: The reliable assessment of the stability of saturated slopes becomes a challenging task when slopes are consisting of discontinuous materials and containing pre-existing joints. The discontinuous nature of the slopes' material could increase the overall permeability of the slope, while existing joints facilitate groundwater leakage through the joint surfaces into the slope which subsequently exerts a major impact on deformation and the effective stress distribution. This paper aims to study the Pore Water Pressure (PWP) distribution changes in a saturated fractured slope by conducting advanced coupled pore fluid diffusion and stress-strain analyses, while investigating the sensitivity of results to the variation of permeability and leakage properties of fracture surfaces. Modelling of jointed slopes is carried out using the e-Xtended Finite Element Method (XFEM) in conjunction with the Finite Element Method (FEM). In this study, the fluid flow inside the joint is the major focus at which the constitutive response of the fluid inside the joint considers both tangential and normal flows. To demonstrate the state-of-the-art simulation technique presented in this paper, simulation of a fractured slope at the second largest open-pit mine in Australia is performed as a case study. This study shows the effect of a variable leak-off coefficient of the joint surfaces and the permeability magnitude on the pore water pressure distribution.
- Description: This research has been supported financially by the Earth Resources Regulation of the Victorian State Government Department of Economic Development, Jobs, Transport and Resources. The first and second authors are funded by the GHERG LV Batter Stability Project Scholarship and Faculty Tuition Scholarship of Federation University Australia.
The orbital displacer: Implications and applications
- Authors: Spark, Ian , Lu, Kui
- Date: 2019
- Type: Text , Book chapter
- Relation: Positive Displacement Machines: Modern Design Innovations and Tools p. 3-35
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- Description: The significance of the orbital displacer may well extend well beyond its application as the basis of a four-stroke internal combustion engine. For example, its inherently high swept volume to total volume ratio can be further increased by combining the original orbital displacer with an everted (i.e. inside-out) orbital displacer to form a hybrid orbital displacer with an even higher swept volume to total volume ratio. Furthermore, the orbital motion of the piston can be used to open and close ports to produce any desired port timing with the same frequency as the orbiting of the piston. These together with other pertinent features will be considered under the following headings: 1. Introduction, 2. Swept volume to total volume ratio, 3. Working volume as a function of crank angle, 4. Minimum geometrically necessary clearance volume as a function of displacer geometry, 5. Valveless port timing, 6. Support of the orbiting piston and vanes, 7. Balancing of the orbital piston and vanes, 8. Sealing of the working volume, 9. Frictional losses and lubrication, 10. Combustion in orbital displacers, 11. Cooling of orbital engines, 12. Manufacturing processes and materials. The above pertinent features will be discussed with reference to the following applications of the orbital displacer: orbital two-stroke engine, orbital hydraulic pumps and motors, orbital pneumatic compressors and motors, orbital Rankine (steam) engine, and orbital 6 cc model aircraft engine. Engineering students have found orbital displacer projects stimulating in the originality required, as they invariably had to go back to first principles to solve problems. © 2020 Elsevier Inc. All rights reserved.
Seasonal movement prediction of tropical cyclone over the North Indian Ocean by using atmospheric climate variables in statistical models
- Authors: Wahiduzzaman, Md , Yeasmin, Alea , Luo, Jing-Jia
- Date: 2020
- Type: Text , Journal article
- Relation: Atmospheric Research Vol. 245, no. (2020), p. 1-13
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- Description: In this study, the contribution of atmospheric climate variables to the prediction skill of tropical cyclone (TC) activity over the North Indian Ocean (NIO) has been investigated. Statistical forecast models are developed through generalised linear model (GLM) and generalised additive model (GAM) for tropical cyclone trajectories over the NIO using atmospheric climate variables as predictors. TC from the Joint Typhoon Warning Centre and sets of climate predictor data were analysed for a period of 35-year (1979-2013). The velocity field is predicted by fitting GAM in each month and season. Hindcast validation method is applied to assess the reliability of the model. The skill of the GAM model is compared with GLM and found to be more successful in forecasting TC movement over the NIO region.
- Description: M.Wahiduzzaman has been supported by Nanjing University of Information Science and Technology, China postdoctoral fellowship fund. Authors are grateful to three anonymous reviewers for their input which improved the quality of the manuscript.
Improving torque performance in reciprocating compressors via asymmetric stroke characteristics
- Authors: Sultan, Ibrahim , Phung, Truong
- Date: 2019
- Type: Text , Book chapter
- Relation: Positive Displacement Machines: Modern Design Innovations and Tools p. 145-162
- Full Text: false
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- Description: Reciprocating compressors enjoy a considerable popularity in industry due to their ability to attain high pressure levels at a range of crankshaft speeds. This chapter is intended to show that it is possible to obtain a considerable improvement in the performance of these compressors by modifying the design of their drives. Instead of the traditional slider-crank mechanism which has been used as a drive since the compressor industry started, it is now possible to replace this drive by more sophisticated ones which feature more flexible stroke designs. The chapter will offer a mathematical model for the workings of reciprocating compressor and demonstrate a candidate drive linkage. An example, presented at the end of the chapter, will demonstrate how the candidate drive linkage is optimized to reduce the torque acting on the compressor crank shaft and hence improve operation and reduce the stresses acting on various components. © 2020 Elsevier Inc. All rights reserved.
Thirty-seven jump-landing biomechanical variables are associated with asymptomatic patellar tendon abnormality and patellar tendinopathy : A systematic review
- Authors: Harris, Meaghan , Schultz, Adrian , Drew, Michael , Rio, Ebonie , Adams, Stuart , Edwards, Suzi
- Date: 2020
- Type: Text , Journal article , Review
- Relation: Physical Therapy in Sport Vol. 45, no. (2020), p. 38-55
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- Description: Objective: To identify studies that report three-dimensional (3D) biomechanical analysis of jump-landing tasks in relation to athletes with current patellar tendinopathy (PT), and/or asymptomatic with history of PT or patellar tendon abnormality (PTA) on diagnostic imaging. Methods: Five electronic databases were searched. Included articles were required to: (1) investigate the 3D biomechanics of a jump-landing task; (2) be cross-sectional or longitudinal in design; and (3) include participants that had symptomatic PT, were asymptomatic with a history of PT, asymptomatic with PTA on diagnostic imaging and/or asymptomatic with an unknown pathology or PT history. Results: Thirty-seven statistically significant jump-landing variables were associated with PT, history of PT and/or PTA. The only consistent variable that could be replicated between studies was knee flexion angle at initial foot-ground contact (IC) and an altered hip flexion/extension strategy during a horizontal land phase of a vertical stop-jump. Conclusion: Isolated vertical landings or take-offs alone may not be sensitive enough to identify key jump-landing variables associated with PT, thus clinicians and researchers should incorporate a whole jump-landing task with a horizontal landing component. Sagital plane hip and knee kinematics in a horizontal landing phase appear to provide the most valuable information for evaluating those with PT. (C) 2020 Elsevier Ltd. All rights reserved.
Application of scaled boundary finite element method for delamination analysis of composite laminates using cohesive zone modelling
- Authors: Garg, Nikhil , Prusty, Gangadhara , Ooi, Ean Tat , Song, Chongmin , Pearce, Garth , Phillips, Andrew
- Date: 2020
- Type: Text , Journal article
- Relation: Composite Structures Vol. 253, no. (2020), p. 1-10
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- Description: In this paper, the scaled boundary finite element method (SBFEM) is evaluated for two-dimensional delamination analysis of composite laminates. The delamination phenomenon was studied using cohesive zone modelling (CZM). A bi-linear (triangular) traction-separation law was used to describe the interface behaviour, which was modelled using zero-thickness interface elements. Local arc-length solution technique was used to solve the non-linearity due to the interface behaviour. In this research, pure Mode I and Mode II as well as mixed mode delamination studies have been conducted using the SBFEM formulation. A variety of numerical experiments were performed. Good agreement was observed between the SBFEM simulation and the available numerical and experimental results in the open literature. A comparison between the SBFEM and other traditional methods shows that the presented formulation can solve the same physical problem with a reduction in the computational cost by more than half. The study highlights the advantages of SBFEM over other methods for modelling delamination in composite laminates using CZM.
- Description: This project is conducted within the ARC Training Centre for Automated Manufacture of Advanced Composites (IC160100040), supported by the Commonwealth of Australia under the Australian Research Council's Industrial Transformation Research Program.
Cardiac energetics
- Authors: Han, June-Chiew , Tran, Kenneth , Taberner, Andrew , Chapman, Brian , Loiselle, Denis
- Date: 2018
- Type: Text , Book chapter
- Relation: Muscle and Exercise Physiology p. 505-539
- Full Text: false
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- Description: The heart is a molecular machine that directly converts the chemical energy of ATP into heat and work. We detail the fundamental thermodynamics underpinning cardiac energy conversion, with interest placed on the efficiency of the conversion. We describe some of the numerous experimental techniques and cardiac preparations (in situ, in vitro, ex vivo, and in vivo) that allow the separation of cardiac energy expenditure into conceptually distinct components: basal metabolism, activation metabolism, force generation, myocyte shortening, and the resultant achievement of force-length work (at the level of the myocyte) and pressure-volume work (at the level of the whole organ). Our focus on experimental results related to physical exercise is supplemented by inclusion of thermodynamically-constrained mathematical simulations of the effects of exercise on the energetics of the heart. © 2019 Elsevier Inc. All rights reserved.
Trade agreements and the risks for the nursing workforce, nursing practice and public health : A scoping review
- Authors: Kidgell, Dianna , Hills, Danny , Griffiths, Debra , Endacott, Ruth
- Date: 2020
- Type: Text , Journal article , Review
- Relation: International Journal of Nursing Studies Vol. 109, no. (2020), p. 1-10
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- Description: Background: Trade agreements in the 21st century have evolved to include provisions that affect domestic public policy and public health in signatory countries. There are growing calls for health professionals and public health advocates to pursue an active advisory role in trade negotiations in order to anticipate and prevent negative outcomes for health services and public health. Aim: This scoping review explored current literature to identify existing knowledge of the implications of trade agreements for the nursing workforce, nursing practice and public health using as an example the 2018 'Comprehensive and Progressive Agreement for Trans-Pacific Partnership'. Design: Scoping review Data sources: Emerald Insight, Informit, Ovid MEDLINE, PubMed, ProQuest, Scopus, and a number of specialist Economics, International Trade and Business, and International Relations databases. Grey literature included national and international policy documents. Review method: Literature was selected according to extraction field criteria, supplemented by hand searching of relevant grey literature and snowballing references from the selected literature reference lists. Analysis was undertaken to identify key themes emerging from the literature. Review results: Six key themes relevant to nursing workforce, nursing practice or public health were 1. Lack of consultation with public health and health professionals in trade negotiations; 2. Implications of strengthened intellectual property provisions for equitable access to medicines (including biologics) and medical devices; 3. Threats to government capacity to regulate domestic policy for public health and health services through 'Investor State Dispute Settlement' provisions 4. Threats to government capacity to regulate domestic policy for public health and health services through 'Regulatory Coherence' 5. Potential limited benefits to communities and increased health inequities 6. Potential implications of increased temporary migration. Gaps were identified in the literature for implications for nursing practice and the nursing workforce from regulatory and labour provisions of trade agreements. Conclusions: The analysis of the literature reviewed is of international importance for the nursing workforce, nursing practice and public health. Policymakers must anticipate and respond to how the inclusion of labour or regulatory provisions in trade agreements will affect nursing practice and the nursing workforce, and how this may subsequently impact on the health of communities globally. (C) 2020 Elsevier Ltd. All rights reserved.
A filled function method for nonlinear equations
- Authors: Wu, Zhiyou , Mammadov, Musa , Bai, Fusheng , Yang, Y. J.
- Date: 2007
- Type: Text , Journal article
- Relation: Applied Mathematics and Computation Vol. 189, no. 2 (2007), p. 1196-1204
- Full Text: false
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- Description: In this paper, we propose a new global optimization approach based on the filled function method for solving box-constrained systems of nonlinear equations. The special properties of optimization problem are employed to construct a novel filled function. The objective function value can be reduced by half in each iteration of our filled function algorithm. Several numerical examples are presented to illustrate the efficiency of the present approach.
- Description: C1
- Description: 2003005618
Item response theory analysis of the spiritual well-being questionnaire
- Authors: Gomez, Rapson , Fisher, John
- Date: 2005
- Type: Text , Journal article
- Relation: Personality and Individual Differences Vol. 38, no. 5 (2005), p. 1107-1121
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- Description: Recently, Gomez and Fisher (2003) published the Spiritual Well-Being Questionnaire (SWBQ). This is a self-rating measure with separate 5-item scales for personal, communal, environmental, and transcendental spiritual well-being. This study used item response theory (IRT) to examine the psychometric properties of these scales. A sample comprising 4462 participants from mainly secondary schools and universities completed the SWBQ. Samejima's graded response model was used for the analyses. The results showed that the discrimination parameters for all items in the four scales were moderate to large. The threshold parameters showed adequate representation of the relevant traits from low to the mean trait level for personal, communal and environmental items, and from low to moderately high trait level for the transcendental items. With the exception of five items, all other items showed good item information function values, and therefore acceptable reliability. The findings also indicated that the number of response options could be decreased and increased at the low and high trait levels, respectively. Thus while there was general support for the psychometric properties of the SWBQ from an IRT perspective, there were also indications that this measure can be further improved. © 2004 Published by Elsevier Ltd.
- Description: C1
- Description: 2003001243
A new filled function method for nonlinear equations
- Authors: Lin, Yongjian Jian , Yang, Y. , Mammadov, Musa
- Date: 2009
- Type: Text , Journal article
- Relation: Applied Mathematics and Computation Vol. , no. (2009), p.
- Full Text: false
- Description: In this paper, a new global optimization approach based on the filled function method is proposed for solving box-constrained systems of nonlinear equations. We first convert the nonlinear system into an equivalent global optimization problem, and then propose a new filled function method to solve the converted global optimization problem. Several numerical examples are presented and solved by using different local minimization methods, which illustrate the efficiency of the present approach. © 2009 Elsevier Inc. All rights reserved.
Determining the intra- and inter-observer reliability of screening tools used in sports injury research
- Authors: Hayen, Andrew , Dennis, Rebecca , Finch, Caroline
- Date: 2007
- Type: Text , Journal article
- Relation: Journal of Science and Medicine in Sport Vol. 10, no. 4 (2007), p. 201-210
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- Description: Sports injury etiological studies explore the relationships between potential injury risk factors and injury outcomes. The ability of such studies to clearly identify intrinsic risk factors for sports injury depends on the accuracy of their measurement. Measurements need to be reproducible over time and repeatable by different observers, as well as within a given individual. The importance of the reliability of pre-participation screening protocols and other clinical assessment tools has been identified in a number of published studies. However, a review of these studies indicates that a variety of statistical techniques have been used to calculate intra- and inter-observer reliability. While the intra-class correlation coefficient (ICC) is the most often cited measure, a range of statistical approaches to estimating ICCs have been used. It is therefore difficult to determine which statistical method is most appropriate in the context of measuring intrinsic risk factors in sports injury research. This paper summarises a statistical method for the concurrent assessment of intra- and inter-observer reliability and presents an argument for why this approach should be adopted by sports injury researchers using screening protocols that collect continuous data.
- Description: C1
- Description: 2003005882
An evaluation of a new test of reactive agility and its relationship to sprint speed and change of direction speed
- Authors: Sheppard, Jeremy , Young, Warren , Doyle, Tim , Sheppard, T. A. , Newton, Robert
- Date: 2006
- Type: Text , Journal article
- Relation: Journal of Science and Medicine in Sport Vol. 9, no. 4 (2006), p. 342-349
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- Description: The purpose of this study was to evaluate the reliability and validity of a new test of agility, the reactive agility test (RAT), which included anticipation and decision-making components in response to the movements of a tester. Thirty-eight Australian football players took part in the study, categorized into either a higher performance group (HPG) (n = 24) or lower performance group (LPG) (n = 14) based on playing level from the previous season. All participants undertook testing of a 10 m straight sprint (10 mSS), a 8-9 m change of direction speed test (CODST), and the RAT. Test-retest and inter-tester reliability testing measures were conducted with the LPG. The intra-class correlation (ICC) of the RAT was 0.870, with no significant (p < 0.05) difference between the test results obtained on the first and second test sessions using a t-test. A dependent samples t-test revealed no significant (p < 0.05) difference between the test results of two different testers with the same population. The HPG were significantly (p = 0.001) superior to those of the LPG on the RAT, with no differences observed on any other variable. The RAT is an acceptably reliable test when considering both test-retest reliability, as well as inter-rater reliability. In addition, the test was valid in distinguishing between players of differing performance level in Australian football, while the 10 mSS and CODST were not. This result suggests that traditional closed skill sprint and sprint with direction change tests may not adequately distinguish between players of different levels of competition in Australian football. © 2006 Sports Medicine Australia.
- Description: C1
- Description: 2003002132
Traditional accountants and business professionals : Portraying the accounting profession after Enron
- Authors: Carnegie, Garry , Napier, Christopher
- Date: 2010
- Type: Text , Journal article
- Relation: Accounting, Organizations and Society Vol. 35, no. 3 (2010), p. 360-376
- Full Text: false
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- Description: Society's perception of the legitimacy of the accounting profession and its members is grounded in the verbal and visual images of accountants that are projected not only by accountants themselves but also by the media. The paper uses the critical literature on stereotypes to examine how books written for a general readership on Enron and other recent corporate failures portray accountants and accounting, and the implications their authors draw for corporate governance and the survival of the financial system. The paper explores how commentators have analyzed the changing activities of accountants (including the rise of consulting) and have contrasted the personalities of "founding fathers" of the US accounting profession with their early 21st-century successors. The paper concludes that changing stereotypes of accountants are evidence of "negative signals of movement" for accounting as a profession. © 2009 Elsevier Ltd. All rights reserved.
Colour and texture of apples high pressure processed in pineapple juice
- Authors: Perera, Niranjalie , Gamage, Thambaramala , Wakeling, Lara , Gamlath, G. , Versteeg, Cornelis
- Date: 2010
- Type: Text , Journal article
- Relation: Innovative Food Science and Emerging Technologies Vol. 11, no. 1 (2010), p. 39-46
- Full Text: false
- Description: Cubes of Granny Smith and Pink Lady apples were vacuum packed in barrier bags with 0% to 50% (v/v) pineapple juice (PJ) at 20°Bx and subjected to high pressure processing (HPP) at 600 MPa for 1–5 min (22 °C). The in-pack total colour change (ΔE) was observed over 4 weeks at 4 °C. Within <1 week of storage at 4 °C, texture, polyphenoloxidase, pectinmethylesterase activities, changes in ΔE and visual browning after opening the bags during air exposure (22 °C; 21% O2 ) for 5 h were also monitored. During the 4 weeks storage in bag visible colour changes were not observed. Texture and ΔE after 5 h air exposure were significantly affected by the apple variety, HPP time and % PJ used. The combined treatment significantly reduced residual PPO activity while PME activity was not affected in both varieties. Pineapple juice in combination with HPP could be used as a natural preservation system for minimally processed apples. Industrial relevance: Browning upon opening the packs and during air exposure can adversely affect the quality of fresh-cut fruits. Combined treatment of high pressure processing (HPP) and use of pineapple juice has the potential to prevent browning for several hours giving sufficient time for presentation and use in domestic and foodservice environment where high quality fresh-like fruit is required.
- Description: Cubes of Granny Smith and Pink Lady apples were vacuum packed in barrier bags with 0% to 50% (v/v) pineapple juice (PJ) at at 20°Bx and subjected to high pressure processing (HPP) at 600 MPa for 1-5 min (22 °C). The in-pack total colour change (
Assessment of learning in contemporary nurse education : Do we need standardised examination for nurse registration?
- Authors: Wellard, Sally , Bethune, Elizabeth , Heggen, Kristin
- Date: 2007
- Type: Text , Journal article
- Relation: Nurse Education Today Vol. 27, no. 1 (2007), p. 68-72
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- Description: In Australia and Norway final examinations to determine eligibility for registration as a nurse were discontinued during the period when nurse education moved into the higher education sector. In response to recent calls for the reintroduction of final examinations we explore the range of knowledge needs for the practice of nursing. These various forms of knowledge demand different forms of mediation and acquisition as well as assessment. There are numerous problems identified in the literature about the shortcomings of examinations as the foundation of assessing clinically based professions. There is a need to develop systems of appropriate assessment to ensure that graduates of nursing demonstrate adequate knowledge and competence to enter their profession. © 2006 Elsevier Ltd. All rights reserved.
- Description: C1
- Description: 2003002546
Sport stadia governance
- Authors: Hoye, Russell , Nicholson, Matthew
- Date: 2010
- Type: Text , Journal article
- Relation: Sport Management Review Vol. 13, no. 2 (2010), p. 171-178
- Full Text: false
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- Description: This case concerns the fictional city of Urbanville, the state capital of Northern Australia, a pseudonym for one of Australia's eight States and Territories, where the State and municipal governments have decided to invest $600 M in the construction of a new sport stadium. The case explores the question of how the stadium will be governed once it has been constructed. The case outlines the key issues and challenges posed by Urbanville's existing sport stadia infrastructure; current issues among stakeholders and their use of existing stadia in Urbanville; and possible choices for the governance arrangements of the new stadium. © 2009 Sport Management Association of Australia and New Zealand.
Graphs of order two less than the Moore bound
- Authors: Miller, Mirka , Simanjuntak, Rinovia
- Date: 2008
- Type: Text , Journal article
- Relation: Discrete Mathematics Vol. 308, no. 13 (2008), p. 2810-2821
- Full Text: false
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- Description: The Moore bound for a directed graph of maximum out-degree d and diameter k is Md,k=1+d+d2++dk. It is known that digraphs of order Md,k (Moore digraphs) do not exist for d>1 and k>1. Similarly, the Moore bound for an undirected graph of maximum degree d and diameter k is . Undirected Moore graphs only exist in a small number of cases. Mixed (or partially directed) Moore graphs generalize both undirected and directed Moore graphs. In this paper, we shall show that all known mixed Moore graphs of diameter k=2 are unique and that mixed Moore graphs of diameter k3 do not exist.
- Description: C1
Maternal psychosocial predictors of controlling parental feeding styles and practices
- Authors: Mitchell, Sarah , Brennan, Leah , Hayes, Louise , Miles, Cara L.
- Date: 2009
- Type: Text , Journal article
- Relation: Appetite Vol. 53, no. 3 (2009), p. 384-389
- Full Text: false
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- Description: The aim of the current study was to explore the relative contribution of parental depression, anxiety and stress and parenting satisfaction and efficacy to the explanation of variance in controlling parental feeding styles and practices. The sample comprised 124 mothers (M = 36.80 years, SD = 4.62 years) who reported on both themselves and a selected child (59 male, 65 female; M = 6.46 years, SD = 0.95 years). Mothers completed several questionnaires examining demographic information, parental feeding styles, parental feeding practices, parental depression, anxiety and stress and parenting satisfaction and efficacy. Parenting satisfaction contributed significantly to the prediction of the parental feeding practice pressure to eat. Parenting satisfaction and parental anxiety contributed significantly to the prediction of the parental feeding practice restriction. The results of this study provide important insight into maternal characteristics associated with the use of controlling parental feeding styles and practices. © 2009 Elsevier Ltd. All rights reserved.