397 resultados para Acornley, Agnes Rebecca.
Resumo:
Based on regional-scale studies, aboveground production and litter decomposition are thought to positively covary, because they are driven by shared biotic and climatic factors. Until now we have been unable to test whether production and decomposition are generally coupled across climatically dissimilar regions, because we lacked replicated data collected within a single vegetation type across multiple regions, obfuscating the drivers and generality of the association between production and decomposition. Furthermore, our understanding of the relationships between production and decomposition rests heavily on separate meta-analyses of each response, because no studies have simultaneously measured production and the accumulation or decomposition of litter using consistent methods at globally relevant scales. Here, we use a multi-country grassland dataset collected using a standardized protocol to show that live plant biomass (an estimate of aboveground net primary production) and litter disappearance (represented by mass loss of aboveground litter) do not strongly covary. Live biomass and litter disappearance varied at different spatial scales. There was substantial variation in live biomass among continents, sites and plots whereas among continent differences accounted for most of the variation in litter disappearance rates. Although there were strong associations among aboveground biomass, litter disappearance and climatic factors in some regions (e.g. U.S. Great Plains), these relationships were inconsistent within and among the regions represented by this study. These results highlight the importance of replication among regions and continents when characterizing the correlations between ecosystem processes and interpreting their global-scale implications for carbon flux. We must exercise caution in parameterizing litter decomposition and aboveground production in future regional and global carbon models as their relationship is complex.
Resumo:
Food Sovereignty (food freedom) is about empowering people to develop their own local food system. Food Sovereignty challenges designers to enable people to innovate the local food system, rather than having a food system which is dictated by corporate interests and failed business ethics. Communities are realising the potential for design to assist in the innovation process, and add strategic value to potentially localise the food system. Design Led Innovation (DLI) offers a strategic framework to address large-scale cultural, systemic and economic changes. The DLI approach empowers communities to take organised action to achieve a healthy, prosperous and happy way of life. DLI can assist with business models in the business world and it is evident this approach can assist with creating social change too. This paper presents on an emerging research agenda aimed to assist designer’s focus from individuals and systems to communities and urban problems. This paper also presents the research proposition that DLI and service design coupled with social entrepreneurial ventures such as local food projects and creative community inventions, have the potential to enable social innovation for healthy and happy communities.
Resumo:
This paper presents and discusses organisational barriers and opportunities arising from the dissemination of design led innovation within a leading Australian airport corporation. This research is part of a greater action research program which aims to integrate design as a strategic capability through design led innovation within Australian businesses. Findings reveal that there is an opportunity to employ the theoretical framework and tools of design led innovation in practice to build collaborative idea generation by involving customers and stakeholders within the proposal of new to world propositions. The iterative gathering of deep customer insights also provided an opportunity to leverage a greater understanding of stakeholders and customers in strengthening continuing business partnerships through co-design. Challenges to the design led approach include resistance to the exploratory nature of gathering deep customer insights, the testing of long held assumptions and market data, and the disruption of an organisational mindset geared toward risk aversion instilled within the aviation industry. The implication from these findings is that design led innovation can provide the critical platform to allow for a business to grow and sustain internal design capabilities necessary to challenge prevailing assumptions about how its business model operates to deliver value to customers and stakeholders alike. The platform of design led innovation also provides an avenue to support a cultural transformation towards anticipating future needs necessary for establishing a position of leadership within the broader economic environment.
Resumo:
Introduction Patients with virally mediated head and neck cancer (VMHNC) often present with advanced nodal disease that is highly radioresponsive as demonstrated by tumour and nodal regression during treatment. The resultant changes may impact on the planned dose distribution and so adversely affect the therapeutic ratio. The aim of this study was to evaluate the dosimetric effect of treatment-induced anatomical changes in VMHNC patients who had undergone a re-plan. Methods Thirteen patients with virally mediated oropharyngeal or nasopharyngeal cancer who presented for definitive radiotherapy between 2005 and 2010 and who had a re-plan generated were investigated. The dosimetric effect of anatomical changes, was quantified by comparing dose volume histograms (DVH) of primary and nodal gross target volumes and organs at risk (OAR), including spinal cord and parotid glands, from the original plan and a comparison plan. Results Eleven 3DCRT and 2 IMRT plans were evaluated. Dose to the spinal cord and brainstem increased by 4.1% and 2.6%, respectively. Mean dose to the parotid glands also increased by 3.5%. In contrast, the dose received by 98% of the primary and nodal gross tumour volumes decreased by 0.15% and 0.3%, respectively when comparing the initial treatment plan to the comparison plan. Conclusion In this study, treatment-induced anatomical changes had the greatest impact on OAR dose with negligible effect on the dose to nodal gross tumour volumes. In the era of intensity modulated radiotherapy (IMRT), accounting for treatment-induced anatomical changes is important as focus is placed on minimising the acute and long-term side effects of treatment.
Resumo:
Objectives Hospital-acquired bloodstream infections are known to increase the risk of death and prolong hospital stay, but precise estimates of these two important outcomes from well-designed studies are rare, particularly for non-intensive care unit (ICU) patients. We aimed to calculate accurate estimates, which are vital for estimating the economic costs of hospital-acquired bloodstream infections.
Resumo:
Background & Aims: Access to sufficient amounts of safe and culturally-acceptable foods is a fundamental human right. Food security exists when all people, at all times, have physical, social, and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life. Food insecurity therefore occurs when the availability or access to sufficient amounts of nutritionally-adequate, culturally-appropriate and safe foods, or, the ability to acquire such foods in socially-acceptable ways, is limited. Food insecurity may result in significant adverse effects for the individual and these outcomes may vary between adults and children. Among adults, food insecurity may be associated with overweight or obesity, poorer self-rated general health, depression, increased health-care utilisation and dietary intakes less consistent with national recommendations. Among children, food insecurity may result in poorer self or parent-reported general health, behavioural problems, lower levels of academic achievement and poor social outcomes. The majority of research investigating the potential correlates of food insecurity has been undertaken in the United States (US), where regular national screening for food insecurity is undertaken using a comprehensive multi-item measurement. In Australia, screening for food insecurity takes place on a three yearly basis via the use of a crude, single-item included in the National Health Survey (NHS). This measure has been shown to underestimate the prevalence of food insecurity by 5%. From 1995 – 2004, the prevalence of food insecurity among the Australian population remained stable at 5%. Due to the perceived low prevalence of this issue, screening for food insecurity was not undertaken in the most recent NHS. Furthermore, there are few Australian studies investigating the potential determinants of food insecurity and none investigating potential outcomes among adults and children. This study aimed to examine these issues by a) investigating the prevalence of food insecurity among households residing in disadvantaged urban areas and comparing prevalence rates estimated by the more comprehensive 18-item and 6-item United States Department of Agriculture (USDA) Food Security Survey Module (FSSM) to those estimated by the current single-item measure used for surveillance in Australia and b) investigating the potential determinants and outcomes of food insecurity, Methods: A comprehensive literature review was undertaken to investigate the potential determinants and consequences of food insecurity among developed countries. This was followed by a cross-sectional study in which 1000 households from the most disadvantaged 5% of Brisbane areas were sampled and data collected via mail-based survey (final response rate = 53%, n = 505). Data were collected for food security status, sociodemographic characteristics (household income, education, age, gender, employment status, housing tenure and living arrangements), fruit and vegetable intakes, meat and take-away consumption, presence of depressive symptoms, presence of chronic disease and body mass index (BMI) among adults. Among children, data pertaining to BMI, parent-reported general health, days away from school and activities and behavioural problems were collected. Rasch analysis was used to investigate the psychometric properties of the 18-, 10- and 6-item adaptations of the USDA-FSSM, and McNemar's test was used to investigate the difference in the prevalence of food insecurity as measured by these three adaptations compared to the current single-item measure used in Australia. Chi square and logistic regression were used to investigate the differences in dietary and health outcomes among adults and health and behavioural outcomes among children. Results were adjusted for equivalised household income and, where necessary, for indigenous status, education and family type. Results: Overall, 25% of households in these urbanised-disadvantaged areas reported experiencing food insecurity; this increased to 34% when only households with children were analysed. The current reliance on a single-item measure to screen for food insecurity may underestimate the true burden among the Australian population, as this measure was shown to significantly underestimate the prevalence of food insecurity by five percentage points. Internationally, major potential determinants of food insecurity included poverty and indicators of poverty, such as low-income, unemployment and lower levels of education. Ethnicity, age, transportation and cooking and financial skills were also found to be potential determinants of food insecurity. Among Australian adults in disadvantaged urban areas, food insecurity was associated with a three-fold increase in experiencing poorer self-rated general health and a two-to-five-fold increase in the risk of depression. Furthermore, adults from food insecure households were twoto- three times more likely to have seen a general practitioner and/or been admitted to hospital within the previous six months, compared to their food secure counterparts. Weight status and intakes of fruits, vegetables and meat were not associated with food insecurity. Among Australian households with children, those in the lowest tertile were over 16 times more likely to experience food insecurity compared to those in the highest tertile for income. After adjustment for equivalised household income, children from food insecure households were three times more likely to have missed days away from school or other activities. Furthermore, children from food insecure households displayed a two-fold increase in atypical emotions and behavioural difficulties. Conclusions: Food insecurity is an important public health issue and may contribute to the burden on the health care system through its associations with depression and increased health care utilisation among adults and behavioural and emotional problems among children. Current efforts to monitor food insecurity in Australia do not occur frequently and use a tool that may underestimate the prevalence of food insecurity. Efforts should be made to improve the regularity of screening for food insecurity via the use of a more accurate screening measure. Most of the current strategies that aim to alleviate food insecurity do not sufficiently address the issue of insufficient financial resources for acquiring food; a factor which is an important determinant of food insecurity. Programs to address this issue should be developed in collaboration with groups at higher risk of developing food insecurity and should incorporate strategies to address the issue of low income as a barrier to food acquisition.
Resumo:
Objective Surveillance programs and research for acute respiratory infections in remote Aboriginal communities are complicated by difficulties in the storage and transport of frozen samples to urban laboratories for testing. This study assessed the sensitivity of a simple method for transporting respiratory samples from a remote setting for viral PCR compared with frozen specimens. Methods We sampled every individual who presented to a remote Aboriginal community clinic in a non-epidemic respiratory season. Two anterior nasal swabs were collected from each participant. The left nare specimen was mailed to the laboratory via routine postal services. The right nare specimen was transported frozen. Testing for 16 viruses was undertaken using real-time multiplex PCR. Results A total of 140 participants were enrolled who contributed 150 study visits. Respiratory illnesses accounted for 10% of the reasons for presentation. Sixty-one viruses were identified in 50 (33.3%) presentations for 40 (28.6%) individuals; bocavirus and rhinovirus were the most common viruses identified (14.0% and 12.6% of episodes respectively). The sensitivity for any virus detected in mailed specimens was 67.2% (95%CI 55.4, 78.9) compared to 65.6% (95%CI 53.7, 77.5) for frozen specimens. Conclusion The mailing of unfrozen nasal specimens from remote communities does not compromise the viability of the specimen for viral studies.
Resumo:
The year 2012 marked 40 years since the introduction of the Child Care Act 1972 and the federal government introduced financial support for the provision of child care services in Australia. Significant changes have occurred in social, political and theoretical contexts of early childhood education and care (ECEC) during this time. Bringing these to life, this paper investigates archival data of key changes in ECEC in association with oral histories of staff, parents and children associated with The Gowrie Qld during the years 1972‒2012. With narrative analysis considered alongside historical information, two dominant issues emerge as integral to ECEC in the past, now and the future. These are: 1) what constitutes effective teaching and learning in the educational program and 2) professional expectations in ECEC. Building an historical picture, this paper provides for critical reflection on the past to inform current and future practices.
Resumo:
1. Expert knowledge continues to gain recognition as a valuable source of information in a wide range of research applications. Despite recent advances in defining expert knowledge, comparatively little attention has been given to how to view expertise as a system of interacting contributory factors, and thereby, to quantify an individual’s expertise. 2. We present a systems approach to describing expertise that accounts for many contributing factors and their interrelationships, and allows quantification of an individual’s expertise. A Bayesian network (BN) was chosen for this purpose. For the purpose of illustration, we focused on taxonomic expertise. The model structure was developed in consultation with professional taxonomists. The relative importance of the factors within the network were determined by a second set of senior taxonomists. This second set of experts (i.e. supra-experts) also provided validation of the model structure. Model performance was then assessed by applying the model to hypothetical career states in the discipline of taxonomy. Hypothetical career states were used to incorporate the greatest possible differences in career states and provide an opportunity to test the model against known inputs. 3. The resulting BN model consisted of 18 primary nodes feeding through one to three higher-order nodes before converging on the target node (Taxonomic Expert). There was strong consistency among node weights provided by the supra-experts for some nodes, but not others. The higher order nodes, “Quality of work” and “Total productivity”, had the greatest weights. Sensitivity analysis indicated that although some factors had stronger influence in the outer nodes of the network, there was relatively equal influence of the factors leading directly into the target node. Despite differences in the node weights provided by our supra-experts, there was remarkably good agreement among assessments of our hypothetical experts that accurately reflected differences we had built into them. 4. This systems approach provides a novel way of assessing the overall level of expertise of individuals, accounting for multiple contributory factors, and their interactions. Our approach is adaptable to other situations where it is desirable to understand components of expertise.
Predicting invasion in grassland ecosystems: is exotic dominance the real embarrassment of richness?
Resumo:
Invasions have increased the size of regional species pools, but are typically assumed to reduce native diversity. However, global-scale tests of this assumption have been elusive because of the focus on exotic species richness, rather than relative abundance. This is problematic because low invader richness can indicate invasion resistance by the native community or, alternatively, dominance by a single exotic species. Here, we used a globally replicated study to quantify relationships between exotic richness and abundance in grass-dominated ecosystems in 13 countries on six continents, ranging from salt marshes to alpine tundra. We tested effects of human land use, native community diversity, herbivore pressure, and nutrient limitation on exotic plant dominance. Despite its widespread use, exotic richness was a poor proxy for exotic dominance at low exotic richness, because sites that contained few exotic species ranged from relatively pristine (low exotic richness and cover) to almost completely exotic-dominated ones (low exotic richness but high exotic cover). Both exotic cover and richness were predicted by native plant diversity (native grass richness) and land use (distance to cultivation). Although climate was important for predicting both exotic cover and richness, climatic factors predicting cover (precipitation variability) differed from those predicting richness (maximum temperature and mean temperature in the wettest quarter). Herbivory and nutrient limitation did not predict exotic richness or cover. Exotic dominance was greatest in areas with low native grass richness at the site- or regional-scale. Although this could reflect native grass displacement, a lack of biotic resistance is a more likely explanation, given that grasses comprise the most aggressive invaders. These findings underscore the need to move beyond richness as a surrogate for the extent of invasion, because this metric confounds monodominance with invasion resistance. Monitoring species' relative abundance will more rapidly advance our understanding of invasions.
Resumo:
We exploit a voting reform in France to estimate the causal effect of exit poll information on turnout and bandwagon voting. Before the change in legislation, individuals in some French overseas territories voted after the election result had already been made public via exit poll information from mainland France. We estimate that knowing the exit poll information decreases voter turnout by about 12 percentage points. Our study is the first clean empirical design outside of the laboratory to demonstrate the effect of such knowledge on voter turnout. Furthermore, we find that exit poll information significantly increases bandwagon voting; that is, voters who choose to turn out are more likely to vote for the expected winner.
Resumo:
Background It is evident from previous research that the role of dietary composition in relation to the development of childhood obesity remains inconclusive. Several studies investigating the relationship between body mass index (BMI), waist circumference (WC) and/or skin fold measurements with energy intake have suggested that the macronutrient composition of the diet (protein, carbohydrate, fat) may play an important contributing role to obesity in childhood as it does in adults. This study investigated the possible relationship between BMI and WC with energy intake and percentage energy intake from macronutrients in Australian children and adolescents. Methods Height, weight and WC measurements, along with 24 h food and drink records (FDR) intake data were collected from 2460 boys and girls aged 5-17 years living in the state of Queensland, Australia. Results Statistically significant, yet weak correlations between BMI z-score and WC with total energy intake were observed in grades 1, 5 and 10, with only 55% of subjects having a physiologically plausible 24 hr FDR. Using Pearson correlations to examine the relationship between BMI and WC with energy intake and percentage macronutrient intake, no significant correlations were observed between BMI z-score or WC and percentage energy intake from protein, carbohydrate or fat. One way ANOVAs showed that although those with a higher BMI z-score or WC consumed significantly more energy than their lean counterparts. Conclusion No evidence of an association between percentage macronutrient intake and BMI or WC was found. Evidently, more robust longitudinal studies are needed to elucidate the relationship linking obesity and dietary intake.
Resumo:
Heavy-vehicle driving involves a challenging work environment and a high crash rate. We investigated the associations of sleepiness, sleep disorders, and work environment (including truck characteristics) with the risk of crashing between 2008 and 2011 in the Australian states of New South Wales and Western Australia. We conducted a case-control study of 530 heavy-vehicle drivers who had recently crashed and 517 heavy-vehicle drivers who had not. Drivers' crash histories, truck details, driving schedules, payment rates, sleep patterns, and measures of health were collected. Subjects wore a nasal flow monitor for 1 night to assess for obstructive sleep apnea. Driving schedules that included the period between midnight and 5:59 am were associated with increased likelihood of crashing (odds ratio = 3.42, 95% confidence interval: 2.04, 5.74), as were having an empty load (odds ratio = 2.61, 95% confidence interval: 1.72, 3.97) and being a less experienced driver (odds ratio = 3.25, 95% confidence interval: 2.37, 4.46). Not taking regular breaks and the lack of vehicle safety devices were also associated with increased crash risk. Despite the high prevalence of obstructive sleep apnea, it was not associated with the risk of a heavy-vehicle nonfatal, nonsevere crash. Scheduling of driving to avoid midnight-to-dawn driving and the use of more frequent rest breaks are likely to reduce the risk of heavy-vehicle nonfatal, nonsevere crashes by 2–3 times.
Resumo:
Aim: To explore weight status perception and its relation to actual weight status in a contemporary cohort of 5- to 17-year-old children and adolescents. Methods: Body mass index (BMI), derived from height and weight measurements, and perception of weight status (‘too thin’, ‘about right’ and ‘too fat’) were evaluated in 3043 participants from the Healthy Kids Queensland Survey. In children less than 12 years of age, weight status perception was obtained from the parents, whereas the adolescents self-reported their perceived weight status. Results: Compared with measured weight status by established BMI cut-offs, just over 20% of parents underestimated their child's weight status and only 1% overestimated. Adolescent boys were more likely to underestimate their weight status compared with girls (26.4% vs. 10.2%, P < 0.05) whereas adolescent girls were more likely to overestimate than underestimate (11.8% vs. 3.4%, P < 0.05). Underestimation was greater by parents of overweight children compared with those of obese children, but still less than 50% of parents identified their obese child as ‘too fat’. There was greater recognition of overweight status in the adolescents, with 83% of those who were obese reporting they were ‘too fat’. Conclusion: Whilst there was a high degree of accuracy of weight status perception in those of healthy weight, there was considerable underestimation of weight status, particularly by parents of children who were overweight or obese. Strategies are required that enable parents to identify what a healthy weight looks like and help them understand when intervention is needed to prevent further weight gain as the child gets older.
Resumo:
The incidences of skin cancers resulting from chronic ultraviolet radiation (UVR) exposure are on the incline both in Australia and globally. Hence, the cellular and molecular pathways associated with UVR-induced photocarcinogenesis urgently need to be elucidated, in order to develop more robust preventative and treatment strategies against skin cancers. In vitro investigations into the effects of UVR (in particular the highly-mutagenic UVB wavelength) have, to date, mainly involved the use of cell culture and animal models. However, these models possess biological disparities to native skin, which to some extent have limited their relevance to the in vivo situation. To address this, we characterised a 3-dimensional, tissue-engineered human skin equivalent (HSE) model (consisting of primary human keratinocytes cultured on a dermal-derived scaffold) as a representation of a more physiologically-relevant platform to study keratinocyte responses to UVB. Significantly, we demonstrate that this model retains several important epidermal properties of native skin. Moreover, UVB-irradiation of the HSE constructs was shown to induce key markers of photodamage in the HSE keratinocytes, including the formation of cyclobutane pyrimidine dimers, the activation of apoptotic pathways, the accumulation of p53 and the secretion of inflammatory cytokines. Importantly, we also demonstrate that the UVB-exposed HSE constructs retain the capacity for epidermal repair and regeneration following photodamage. Together, our results demonstrate the potential of this skin equivalent model as a tool to study various aspects of the acute responses of human keratinocytes to UVB radiation damage.