Showing papers by "Deakin University published in 2008"
TL;DR: Evidence is provided of the importance of avoiding prolonged uninterrupted periods of sedentary (primarily sitting) time and new public health recommendations regarding breaking up sedentary time that are complementary to those for physical activity are suggested.
Abstract: OBJECTIVE —Total sedentary (absence of whole-body movement) time is associated with obesity, abnormal glucose metabolism, and the metabolic syndrome. In addition to the effects of total sedentary time, the manner in which it is accumulated may also be important. We examined the association of breaks in objectively measured sedentary time with biological markers of metabolic risk.
RESEARCH DESIGN AND METHODS —Participants ( n = 168, mean age 53.4 years) for this cross-sectional study were recruited from the 2004–2005 Australian Diabetes, Obesity and Lifestyle study. Sedentary time was measured by an accelerometer (counts/minute−1 < 100) worn during waking hours for seven consecutive days. Each interruption in sedentary time (counts/min ≥100) was considered a break. Fasting plasma glucose, 2-h plasma glucose, serum triglycerides, HDL cholesterol, weight, height, waist circumference, and resting blood pressure were measured. MatLab was used to derive the breaks variable; SPSS was used for the statistical analysis.
RESULTS —Independent of total sedentary time and moderate-to-vigorous intensity activity time, increased breaks in sedentary time were beneficially associated with waist circumference (standardized β = −0.16, 95% CI −0.31 to −0.02, P = 0.026), BMI (β = −0.19, −0.35 to −0.02, P = 0.026), triglycerides (β = −0.18, −0.34 to −0.02, P = 0.029), and 2-h plasma glucose (β = −0.18, −0.34 to −0.02, P = 0.025).
CONCLUSIONS —This study provides evidence of the importance of avoiding prolonged uninterrupted periods of sedentary (primarily sitting) time. These findings suggest new public health recommendations regarding breaking up sedentary time that are complementary to those for physical activity.
1,399 citations
TL;DR: In this article, the authors examined the associations of objectively measured sedentary time and physical activity with continuous indexes of metabolic risk in Australian adults without known diabetes, and highlighted the importance of decreasing the amount of time spent in physical activity for metabolic health.
Abstract: OBJECTIVE —We examined the associations of objectively measured sedentary time and physical activity with continuous indexes of metabolic risk in Australian adults without known diabetes. RESEARCH DESIGN AND METHODS —An accelerometer was used to derive the percentage of monitoring time spent sedentary and in light-intensity and moderate-to-vigorous–intensity activity, as well as mean activity intensity, in 169 Australian Diabetes, Obesity and Lifestyle Study (AusDiab) participants (mean age 53.4 years). Associations with waist circumference, triglycerides, HDL cholesterol, resting blood pressure, fasting plasma glucose, and a clustered metabolic risk score were examined. RESULTS —Independent of time spent in moderate-to-vigorous–intensity activity, there were significant associations of sedentary time, light-intensity time, and mean activity intensity with waist circumference and clustered metabolic risk. Independent of waist circumference, moderate-to-vigorous–intensity activity time was significantly beneficially associated with triglycerides. CONCLUSIONS —These findings highlight the importance of decreasing sedentary time, as well as increasing time spent in physical activity, for metabolic health.
969 citations
TL;DR: This article examined the relationship between capital formation, energy consumption and real GDP in a panel of G7 countries using panel unit root, panel cointegration, Granger causality and long-run structural estimation.
694 citations
TL;DR: Perceived neighbourhood greenness was more strongly associated with mental health than it was with physical health, whereas the relationship between greenness and mental health was only partly accounted for by recreational walking and social coherence.
Abstract: Background: Studies have shown associations between health indices and access to “green” environments but the underlying mechanisms of this association are not clear. Objectives: To examine associations of perceived neighbourhood “greenness” with perceived physical and mental health and to investigate whether walking and social factors account for the relationships. Methods: A mailed survey collected the following data from adults (n = 1895) in Adelaide, Australia: physical and mental health scores (12-item short-form health survey); perceived neighbourhood greenness; walking for recreation and for transport; social coherence; local social interaction and sociodemographic variables. Results: After adjusting for sociodemographic variables, those who perceived their neighbourhood as highly green had 1.37 and 1.60 times higher odds of better physical and mental health, respectively, compared with those who perceived the lowest greenness. Perceived greenness was also correlated with recreational walking and social factors. When walking for recreation and social factors were added to the regression models, recreational walking was a significant predictor of physical health; however, the association between greenness and physical health became non-significant. Recreational walking and social coherence were associated with mental health and the relationship between greenness and mental health remained significant. Conclusions: Perceived neighbourhood greenness was more strongly associated with mental health than it was with physical health. Recreational walking seemed to explain the link between greenness and physical health, whereas the relationship between greenness and mental health was only partly accounted for by recreational walking and social coherence. The restorative effects of natural environments may be involved in the residual association of this latter relationship.
680 citations
25 Nov 2008-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: The extrusion behavior, texture and tensile ductility of five binary Mg-based alloys have been examined and compared to pure Mg in this article, and the five alloying additions examined were Al, Sn, Ca, La and Gd.
Abstract: The extrusion behaviour, texture and tensile ductility of five binary Mg-based alloys have been examined and compared to pure Mg. The five alloying additions examined were Al, Sn, Ca, La and Gd. When these alloys are compared at equivalent grain size, the La- and Gd-containing alloys show the best ductilities. This has been attributed to a weaker extrusion texture. These two alloying additions, La and Gd, were found to also produce a new texture peak with 〈 1 1 2 ¯ 1 〉 parallel to the extrusion direction. This “rare earth texture” component was found to be suppressed at high extrusion temperatures. It is proposed that the 〈 1 1 2 ¯ 1 〉 texture component arises from oriented nucleation at shear bands.
669 citations
TL;DR: Concerns regarding 'stranger danger' and road safety are described, empirical studies that examine associations between neighbourhood safety and physical activity among youth are discussed, and perceptions of safety between parents and youth are examined.
658 citations
TL;DR: Evidence suggests that even low doses of PA may be protective against depression, and further studies examining the optimal domain of PA for reducing the likelihood of depression are needed.
619 citations
TL;DR: Improved cycling infrastructure in the form of bicycle paths and lanes that provide a high degree of separation from motor traffic is likely to be important for increasing transportation cycling amongst under-represented population groups such as women.
592 citations
TL;DR: The influences on the physical activity behaviors of preschool children are multidimensional and further research is required to enhance an understanding of these influences.
556 citations
TL;DR: Alan Shiell, Penelope Hawe, and Lisa Gold explain why it is important to distinguish the two types of complexity.
Abstract: Although guidelines exist for evaluating complex interventions, they may be of little help in dealing with the multiple effects of interventions in complex systems such as hospitals. Alan Shiell, Penelope Hawe, and Lisa Gold explain why it is important to distinguish the two types of complexity
508 citations
TL;DR: This paper examined whether personality and motivational driver differences exist across three generations of working Australians: Baby Boomers, Gen Xs, and Gen Ys, and found that few meaningful differences were found between the three generations.
Abstract: Purpose – The purpose of this research is to examine whether personality and motivational driver differences exist across three generations of working Australians: Baby Boomers, Gen Xs, and Gen Ys.Design/methodology/approach – Using the Occupational Personality Questionnaire and the Motivation Questionnaire, the study examined cross‐sectional differences in personality and motivational drivers across three generations.Findings – The results are not supportive of the generational stereotypes that have been pervasive in the management literature and the media. Specifically, few meaningful differences were found between the three generations. Moreover, even when differences have been observed, these have related more to age than generation.Research limitations/implications – One of the key limitations is the use of cross‐sectional data. To further explore this issue, it would be interesting to undertake a longitudinal study to assess personality preferences and motivational drivers of the different generatio...
TL;DR: In this paper, a quantitative assessment of the democracy-growth literature is presented, which concludes that democracy has robust, significant, and positive indirect effects through higher human capital, lower inflation, lower political instability, and higher levels of economic freedom.
Abstract: Despite a sizeable theoretical and empirical literature, no firm conclusions have been drawn regarding the impact of political democracy on economic growth. This article challenges the consensus of an inconclusive relationship through a quantitative assessment of the democracy-growth literature. It applies meta-regression analysis to the population of 483 estimates derived from 84 studies on democracy and growth. Using traditional meta-analysis estimators, the bootstrap, and Fixed and Random Effects meta-regression models, it derives several robust conclusions. Taking all the available published evidence together, it concludes that democracy does not have a direct impact on economic growth. However, democracy has robust, significant, and positive indirect effects through higher human capital, lower inflation, lower political instability, and higher levels of economic freedom. Democracies may also be associated with larger governments and less free international trade. There also appear to be country- and region-specific democracy-growth effects. Overall, democracy's net effect on the economy does not seem to be detrimental.
TL;DR: Significant, detrimental dose-response associations of television-viewing time were observed with waist circumference, systolic blood pressure, and 2-h plasma glucose in men and women, and with fasting plasma glucose, triglycerides, and HDL-C in women.
Abstract: Purpose:Among Australian adults who met the public health guideline for the minimum health-enhancing levels of physical activity, we examined the dose-response associations of television-viewing time with continuous metabolic risk variables.Methods:Data were analyzed on 2031 men and 2033 wom
TL;DR: In this article, the authors explored the relationship between loneliness and the need to belong with a sample of 436 volunteer participants drawn from the Australian Unity Wellbeing database Participants completed a survey that included a measure of satisfaction with personal relationships embedded in the Personal Wellbeing Index, the UCLA Loneliness scale, and the Need to Belong Scale.
TL;DR: It is reported that AMP-activated protein kinase (AMPK) regulates GLUT4 transcription through the histone deacetylase (HDAC)5 transcriptional repressor through the signal transduction pathway linking cellular energy charge to gene transcription directed at restoring cellular and whole-body energy balance.
Abstract: OBJECTIVE— Insulin resistance associated with obesity and diabetes is ameliorated by specific overexpression of GLUT4 in skeletal muscle. The molecular mechanisms regulating skeletal muscle GLUT4 expression remain to be elucidated. The purpose of this study was to examine these mechanisms. RESEARCH DESIGN AND METHODS AND RESULTS— Here, we report that AMP-activated protein kinase (AMPK) regulates GLUT4 transcription through the histone deacetylase (HDAC)5 transcriptional repressor. Overexpression of HDAC5 represses GLUT4 reporter gene expression, and HDAC inhibition in human primary myotubes increases endogenous GLUT4 gene expression. In vitro kinase assays, site-directed mutagenesis, and site-specific phospho-antibodies establish AMPK as an HDAC5 kinase that targets S259 and S498. Constitutively active but not dominant-negative AMPK and 5-aminoimidazole-4-carboxamide-1-β-d-ribonucleoside (AICAR) treatment in human primary myotubes results in HDAC5 phosphorylation at S259 and S498, association with 14-3-3 isoforms, and H3 acetylation. This reduces HDAC5 association with the GLUT4 promoter, as assessed through chromatin immunoprecipitation assays and HDAC5 nuclear export, concomitant with increases in GLUT4 gene expression. Gene reporter assays also confirm that the HDAC5 S259 and S498 sites are required for AICAR induction of GLUT4 transcription. CONCLUSIONS— These data reveal a signal transduction pathway linking cellular energy charge to gene transcription directed at restoring cellular and whole-body energy balance and provide new therapeutic targets for the treatment and management of insulin resistance and type 2 diabetes.
TL;DR: This paper examined the influence of ownership type, size, risk profile, profitability and key environmental changes on the bank efficiency using a Tobit regression and found that profit efficiency levels are well below those of cost efficiency, which suggests that the most important inefficiencies are on the revenue side.
TL;DR: Analytical proof that classic mutual information cannot be considered a measure for image fusion performance is provided.
Abstract: The unsuitability of using classic mutual information measure as a performance measure for image fusion is discussed Analytical proof that classic mutual information cannot be considered a measure for image fusion performance is provided
TL;DR: This article conducted a meta-analysis of the aid effectiveness literature and found that the results do have a positive average, but it is small, insignificant and falling, and that much of the variation between studies can be attributed to publication outlet, institutional affiliation, data and specification differences.
TL;DR: In this article, electron backscattering diffraction and Schmid analysis were combined to investigate secondary twinning in the magnesium alloy Mg-3Al-1Zn. But the secondary twin's activation was quite inconsistent with Schmid-type behaviour.
TL;DR: In this paper, the authors extended three residual-based test statistics for cointegration to the cases that take into account two possible regime shifts, and applied them to determine whether the financial markets in the US and the UK are integrated.
Abstract: It is widely agreed in empirical studies that allowing for potential structural change in economic processes is an important issue. In existing literature, tests for cointegration between time series data allow for one regime shift. This paper extends three residual-based test statistics for cointegration to the cases that take into account two possible regime shifts. The timing of each shift is unknown a priori and it is determined endogenously. The distributions of the tests are non-standard. We generate new critical values via simulation methods. The size and power properties of these test statistics are evaluated through Monte Carlo simulations, which show the tests have small size distortions and very good power properties. The test methods introduced in this paper are applied to determine whether the financial markets in the US and the UK are integrated.
TL;DR: This paper explored the role of procedural justice in shaping the public's willingness to assist police in crime control and found that those who view the police as more legitimate are more likely to assist the police to control crime.
Abstract: This paper explores how to increase public cooperation and support for police. To date, only a few studies have attempted to explore the role that procedural justice plays in shaping the public's willingness to assist police in crime control. The present study explores this much neglected field of research using both crosssectional survey data and panel data. The study finds that views about police legitimacy do influence public cooperation with the police, and that those who view the police as more legitimate are more likely to assist police to control crime. The key antecedent of legitimacy is procedural justice; those who are more likely to believe police use procedural justice in their dealings with the public are more likely to perceive police as legitimate.
TL;DR: In this article, a series of alloys have been produced with microalloying additions of rare-earth (RE) elements in the range of 0.1-0.4
TL;DR: A number of factors have the ability to affect phenolic concentrations in virgin olive oil, so it is of great importance to understand these factors in order to preserve the essential health promoting benefits of olive oil phenolic compounds.
Abstract: The Mediterranean diet is associated with a lower incidence of atherosclerosis, cardiovascular disease, and certain types of cancer. The apparent health benefits have been partially attributed to the dietary consumption of virgin olive oil by Mediterranean populations. Most recent interest has focused on the biologically active phenolic compounds naturally present in virgin olive oils. Studies (human, animal, in vivo and in vitro) have shown that olive oil phenolics have positive effects on certain physiological parameters, such as plasma lipoproteins, oxidative damage, inflammatory markers, platelet and cellular function, and antimicrobial activity. Presumably, regular dietary consumption of virgin olive oil containing phenolic compounds manifests in health benefits associated with a Mediterranean diet. This paper summarizes current knowledge on the physiological effects of olive oil phenolics. Moreover, a number of factors have the ability to affect phenolic concentrations in virgin olive oil, so it is of great importance to understand these factors in order to preserve the essential health promoting benefits of olive oil phenolic compounds.
TL;DR: Encouraging 10–12-year-old children to spend more time outdoors may be an effective strategy for increasing physical activity and preventing increases in overweight and obesity.
Abstract: Objective : This study aimed to determine whether time spent outdoors was associated with objectively measured physical activity, body mass index (BMI) z-score and overweight in elementary-school aged children, cross-sectionally and prospectively over 3 years. Methods : Three-year cohort study with data collected during 2001 and 2004. Nineteen randomly selected state elementary schools across Melbourne, Australia. One hundred and eighty eight 5–6-year-old and 360 10–12-year-old children. Baseline parent reports of children’s time spent outdoors during warmer and cooler months, on weekdays and weekends. At baseline and follow-up, children’s moderate and vigorous physical activity (MVPA) was objectively assessed by accelerometry, and BMI zscore and overweight was calculated from measured height and weight. Results : Cross-sectionally, each additional hour outdoors on weekdays and weekend days during the cooler months was associated with an extra 27 min week -1 MVPA among older girls, and with an extra 20 min week -1 MVPA among older boys. Longitudinally, more time outdoors on weekends predicted higher MVPA on weekends among older girls and boys (5 min week -1 ). The prevalence of overweight among older children at follow-up was 27–41% lower among those spending more time outdoors at baseline. Conclusion : Encouraging 10–12-year-old children to spend more time outdoors may be an effective strategy for increasing physical activity and preventing increases in overweight and obesity. Intervention research investigating the effect of increasing time outdoors on children’s physical activity and overweight is warranted.
TL;DR: In this paper, a case study of graduates in science and education is examined to show how the different disciplinary and pedagogic practices of each discourse community impact on student publication, and the importance of giving greater pedagogical attention to writing for publication in higher education.
Abstract: This article addresses the importance of giving greater pedagogical attention to writing for publication in higher education. It recognizes that, while doctoral research is a major source of new knowledge production in universities, most doctoral students do not receive adequate mentoring or structural support to publish from their research, with poor results. Data from a case study of graduates in science and education are examined to show how the different disciplinary and pedagogic practices of each discourse community impact on student publication. It is argued that co‐authorship with supervisors is a significant pedagogic practice that can enhance the robustness and know‐how of emergent scholars as well as their publication output. There is a need, however, to rethink co‐authorship more explicitly as a pedagogic practice, and create more deliberate structures in subject disciplines to scaffold doctoral publication – as it is these structures that influence whether graduates publish as informed profes...
TL;DR: This paper deconstructs the process and investigates the formation of the activated digital network as distinct from the underlying social network, confirming that the social structure of digital networks play a critical role in the spread of a viral message.
Abstract: Viral marketing is a form of peer-to-peer communication in which individuals are encouraged to pass on promotional messages within their social networks. Conventional wisdom holds that the viral marketing process is both random and unmanageable. In this paper, we deconstruct the process and investigate the formation of the activated digital network as distinct from the underlying social network. We then consider the impact of the social structure of digital networks (random, scale free, and small world) and of the transmission behavior of individuals on campaign performance. Specifically, we identify alternative social network models to understand the mediating effects of the social structures of these models on viral marketing campaigns. Next, we analyse an actual viral marketing campaign and use the empirical data to develop and validate a computer simulation model for viral marketing. Finally, we conduct a number of simulation experiments to predict the spread of a viral message within different types of social network structures under different assumptions and scenarios. Our findings confirm that the social structure of digital networks play a critical role in the spread of a viral message. Managers seeking to optimize campaign performance should give consideration to these findings before designing and implementing viral marketing campaigns. We also demonstrate how a simulation model is used to quantify the impact of campaign management inputs and how these learnings can support managerial decision making.
TL;DR: This food-based dietary index is able to discriminate across a variety of sociodemographic factors, health behaviors, and self-assessed health and reflects intakes of key nutrients.
Abstract: Diet indices represent an integrated approach to assessing eating patterns and behaviors. The aim of this study was to develop a comprehensive food-based dietary index to reflect adherence to healthy eating recommendations, evaluate the construct validity of the index using nutrient intakes, and evaluate this index in relation to sociodemographic factors, health behaviors, risk factors, and self-assessed health status. Data were analyzed from adult participants of the Australian National Nutrition Survey who completed a 108-item FFQ and a food habits questionnaire (n = 8220). The dietary guideline index (DGI) consisted of 15 items reflecting the dietary guidelines, including dietary indicators of vegetables and legumes, fruit, total cereals, meat and alternatives, total dairy, beverages, sodium, saturated fat, alcoholic beverages, and added sugars. Diet quality was incorporated using indicators relating to whole-grain cereals, lean meat, reduced/low fat dairy, and dietary variety. We investigated associations between the DGI score, sociodemographic factors, health behaviors, chronic disease risk factors, and nutrient intakes. We found associations between the DGI scores and sex, age, income, area-level socioeconomic disadvantage, smoking, physical activity, waist:hip ratio, systolic blood pressure (males only), and self-assessed health status (females only) (all P < 0.05). Higher DGI scores were associated with lower intakes of energy, total fat, and saturated fat and higher intakes of fiber, beta-carotene, vitamin C, folate, calcium, and iron (P < 0.05). This food-based dietary index is able to discriminate across a variety of sociodemographic factors, health behaviors, and self-assessed health and reflects intakes of key nutrients.
TL;DR: Stable superhydrophobic surfaces with water contact angles over 170 degrees and sliding angles below 7 degrees were produced by simply coating a particulate silica sol solution of co-hydrolysed TEOS/fluorinated alkyl silane with NH(3).
TL;DR: In this paper, a review summarizes the recent progress in electrospun nanofibers, with an emphasis on their applications, and summarizes the functionalities and surface chemistry of the polymer itself.
Abstract: Polymeric nanofiber non-woven materials produced by electrospinning have extremely high surface-to-mass (or volume) ratio and a porous structure with excellent pore-interconnectivity. These characteristics plus the functionalities and surface chemistry of the polymer itself impart the nanofibers with desirable properties for a range of advanced applications. This review summarizes the recent progress in electrospun nanofibers, with an emphasis on their applications.
TL;DR: In this paper, it was shown that the yield stress is a function of the grain size in much the same way as it is for dislocation glide, and that the sensitivity to grain size is typically greater.