Sydney Area Research Articles

Constraining timing of brittle deformation and fault gouge formation in the Sydney Basin

Structural and K–Ar dating studies of gouge in N–S, NNE and E–W-trending faults in four locations in the Sydney–Hunter region are reported. The fault zones are manifest as joint swarms and highly brecciated zones containing gouge with authigenic illite produced as a result of fluid infiltration. Strike-slip movement accompanied by minor dip-slip, normal movement occurred on the NNE faults, with dip slip on N–S and E–W-trending faults. In this study, gouge from a NE-trending, steep, SE-dipping fault showing dip-slip movement at Cut 10, on the Hunter Expressway and from an E–W-trending, steep south-dipping, normal fault at the Westside Open Cut, Lake Macquarie have been analysed. K–Ar dating of illite and illite–smectite in fractions extracted from fault gouges in areas unaffected by a thermal overprint reveals ages varying from 166 to 119 Ma for the <2 μm and finer fractions, and a mean age of ca 120 Ma for the <0.4 μm fraction. In the Sydney area and the Westside Open Cut coal mine, Lake Macquarie, the ages obtained from similar size fractions both for the gouge and for the host rocks are younger (134–76 Ma; av. <0.4 μm = 111 Ma). The data indicate influence of a thermal overprint associated with subsurface magmas emplaced during the early stages of the rifting of eastern Gondwana during the early Cretaceous.

Groundwater resource potential of the Triassic Sandstones of the Southern Sydney Basin: an improved understanding

Groundwater investigations for drought water supply for the greater Sydney area were initiated in the Sydney Basin in late 2004 as part of the NSW Government's Metropolitan Water Plan suite of initiatives to find emergency water-supply sources during a severe drought period. A number of priority areas were drilled and tested between 2004 and 2008 to assess the groundwater resource potential of several Triassic and Permian sandstone units. At Kangaloon in the Southern Highlands, the Triassic fractured Hawkesbury Sandstone aquifers were prospective for emergency water supply with bore yields generally in excess of 3 L/s for most sites with the occasional site in excess of 30 L/s. Water levels were mostly less than 15 metres (m) from the surface with artesian conditions at several sites. The water quality was excellent with the areas within the proposed borefield area all having salinities less than 400 μS/cm. At Leonay–Emu Plains in western Sydney, the Hawkesbury Sandstone was thicker than at Kangaloon, and bore yields were consistently higher with predicted yields (to last several years) assessed to be between 10 and 20 L/s. Artesian conditions prevail to the north of Emu Plains. Water salinities up to 1700 μS/cm were identified with the best water quality below 80 m where the salinities were generally less than 400 μS/cm. At Wallacia, in southwestern Sydney, there was more variability in the permeability of the Hawkesbury Sandstone with predicted bore yields assessed to be between 2 and 10 L/s, although there were a couple of sites with yields of up to 40 L/s. Artesian conditions prevail to the south of Wallacia in the Bents Basin area. Water salinities up to 4300 μS/cm were identified in the Hawkesbury Sandstone with the best water quality below 150 m where the salinities were generally between 400 and 1600 μS/cm. The older Triassic and Permian sandstone units were not prospective for emergency water supply at the locations that were investigated.

Economic evaluation of “healthy beginnings” an early childhood intervention to prevent obesity

To determine the costs and cost-effectiveness of an early childhood home visiting program delivered to families in socio-economically disadvantaged areas of Sydney, Australia during 2007-2010. Economic evaluation of a randomized controlled trial, the healthy beginnings (HB) trial, from the perspective of the health funder. Intervention resources were determined from local health district records in 2012 $AUD. Health-care resource utilization was determined through patient-level data linkage. The cost of HB intervention in the clinical trial over 2 years was $1309 per child (2012 $AUD). The incremental cost-effectiveness ratio was $4230 per unit BMI avoided and $631 per 0.1 reduction in BMI z-score. It was estimated that the program could be delivered in practice for $709 per child; with incremental cost-effectiveness ratios of $2697 per unit BMI avoided and $376 per 0.1 reduction in BMI z-score. We present the first economic evaluation of an effective obesity prevention initiative in early childhood. HB is a moderately priced intervention with demonstrated effectiveness that offers similar or better value for money than existing obesity prevention or treatment interventions targeted at older children.

Tackling the challenges in conducting a 5‐year longitudinal study of the Healthy Beginnings Trial

The Healthy Beginnings Trial is a 5 year longitudinal study of 667 first-time mothers and their babies, conducted in some of the most socially and economically disadvantaged areas of Sydney between 2007 and 2013. The aim was to determine whether a home-based obesity intervention during the first 2 years of life is effective for children at 2, 3.5 and 5 years of age. The details of the results from the 2 year follow up are reported elsewhere, and the 3.5- and 5-year follow-up of the trial is still underway. However, challenges conducting this longitudinal face-to-face survey are yet to be reported.

Housing Supply Elasticity in Sydney Local Government Areas

We report supply elasticity estimates of residential property (houses and apartments) for Local Government Areas (LGAs) in metropolitan Sydney. Using annual data for 1991-2012, the average supply elasticity estimate across all LGAs is 0.2 for houses and 0.8 for apartments. The supply of houses is inelastic in all 43 LGAs; in contrast apartment supply is elastic – greater than unity – in about one-third of LGAs. We develop a model to explain the cross-section variation in supply elasticity across LGAs. For houses, supply elasticity is negatively related to an LGA’s population density, the time taken by a Local Council to process a development application and to various measures of the amount of land in an LGA that is unavailable for new housing development. Variation in supply elasticity for apartments across LGAs is unrelated to any of the available regressors.

High density lipoproteins improve insulin sensitivity in high-fat diet-fed mice by suppressing hepatic inflammation

Obesity-induced liver inflammation can drive insulin resistance. HDL has anti-inflammatory properties, so we hypothesized that low levels of HDL would perpetuate inflammatory responses in the liver and that HDL treatment would suppress liver inflammation and insulin resistance. The aim of this study was to investigate the effects of lipid-free apoAI on hepatic inflammation and insulin resistance in mice. We also investigated apoAI as a component of reconstituted HDLs (rHDLs) in hepatocytes to confirm results we observed in vivo. To test our hypothesis, C57BL/6 mice were fed a high-fat diet (HFD) for 16 weeks and administered either saline or lipid-free apoAI. Injections of lipid-free apoAI twice a week for 2 or 4 weeks with lipid-free apoAI resulted in: i) improved insulin sensitivity associated with decreased systemic and hepatic inflammation; ii) suppression of hepatic mRNA expression for key transcriptional regulators of lipogenic gene expression; and iii) suppression of nuclear factor κB (NF-κB) activation. Human hepatoma HuH-7 cells exposed to rHDLs showed suppressed TNFα-induced NF-κB activation, correlating with decreased NF-κB target gene expression. We conclude that apoAI suppresses liver inflammation in HFD mice and improves insulin resistance via a mechanism that involves a downregulation of NF-κB activation.

Explaining ecological clusters of maternal depression in South Western Sydney.

BackgroundThe aim of the qualitative study reported here was to: 1) explain the observed clustering of postnatal depressive symptoms in South Western Sydney; and 2) identify group-level mechanisms that would add to our understanding of the social determinants of maternal depression.MethodsCritical realism provided the methodological underpinning for the study. The setting was four local government areas in South Western Sydney, Australia. Child and Family practitioners and mothers in naturally occurring mothers groups were interviewed.ResultsUsing an open coding approach to maximise emergence of patterns and relationships we have identified seven theoretical concepts that might explain the observed spatial clustering of maternal depression. The theoretical concepts identified were: Community-level social networks; Social Capital and Social Cohesion; "Depressed community"; Access to services at the group level; Ethnic segregation and diversity; Supportive social policy; and Big business.ConclusionsWe postulate that these regional structural, economic, social and cultural mechanisms partially explain the pattern of maternal depression observed in families and communities within South Western Sydney. We further observe that powerful global economic and political forces are having an impact on the local situation. The challenge for policy and practice is to support mothers and their families within this adverse regional and global-economic context.

Vitamin D Deficiency may be a Risk Factor for Ophthalmopathy in Patients with Graves’ Hyperthyroidism But Not Hashimoto's Thyroiditis

Aims: Apart from its key role in bone metabolism vitamin D plays a role in immune function, cancer prevention and autoimmunity induction. Vitamin D insufficiency (25-50 nmol/L) and deficiency (serum level < 25 nmol/L) are very common in the West Sydney and Blue Mountains areas of Australia. Vitamin D deficiency may also play a role in the development of ophthalmopathy in patients with thyroid autoimmunity. Methods : We have studied a possible relationship between serum vitamin D level and

Quantifying Catastrophic and Climate Impacted Hazards Based on Local Expert Opinions

The analysis of catastrophic and climate impacted hazards is a challenging but important exercise, as the occurrence of such events is usually associated with high damage and uncertainty. Often, at the local level, there is a lack of information on rare extreme events, such that available data is not sufficient to fit a distribution and derive parameter values for the frequency and severity distributions. This paper discusses local assessments of extreme events and examines the potential of using expert opinions in order to obtain values for the distribution parameters. In particular, we illustrate a simple approach, where a local expert is required to only specify two percentiles of the loss distribution in order to provide an estimate for the severity distribution of climate impacted hazards. In our approach, we focus on so-called heavy-tailed distributions for the severity, such as the Lognormal, Weibull and Burr XII distribution. These distributions are widely used to fit data from catastrophic events and can also represent extreme losses or the so-called tail of the distribution. An illustration of the method is provided utilising an example that quantifies the risk of bushfires in a local area in Northern Sydney.

Featured Graphic. A Community-Led Critique of Accessibility of Sydney's Public Transportation Network

The shift from auto-dependent modes of urban transportation has been a key focus of the sustainability literature for over two decades (Low, 2013; Mees, 2010). This literature argues that mobility in cities ought to be addressed through public transportation rather than individualised forms of transport as a pathway to low carbon economies. However, pathways to achieve such a city remain highly contentious. Many authors suggest that citizen action and engagement is a crucial part of efforts to reshape public transportation (Low and Gleeson, 2001; Mees, 2010). The Sydney Alliance, a coalition of over fifty trade union, community, and faith-based organisations, decided through extensive community based discussion to take action on public transport across Sydney. A ‘transport research action team’ was formed to develop a set of principles for public transport in Sydney through discussion with community, academics, activists, bureaucrats, and politicians. As members of the National Tertiary Education Union, both authors have been active members of the Transport Research Action Team. Based on its research, the Alliance is organising to implement these principles to achieve improvements to public transport that will address ‘accessibility gaps’ (Mulley and Daniels, 2010), and contribute to the ‘network effect’ (Dodson et al, 2011; Mees, 2010; Nielsen and Lange, 2005). As part of our campaign work, we produced a map of Sydney to show which parts of the city have access to minimum standards of distance and frequency. The first part of diagram shows the areas of Sydney that are within 400 m walk of a transit node (rail, bus, and ferry stops). The second part shows the area of Sydney that is within 400 m walk of transit nodes that have a minimum service frequency of at least every 15 minutes between 5 am and midnight on any given weekday. The map shows that, while there is comprehensive geographic coverage of transport services across Sydney, there is a spatial concentration of public transport services that meet the minimum standard of a useful, frequent public transport service. It also highlights the gaps in accessibility of these services for large parts of, in particular, Western Sydney. The map informs an ongoing Sydney Alliance campaign to ‘fill in the gaps in the maps’.

Geospatial and epidemiological analysis of severe burns in New South Wales by residential postcodes

BackgroundBurns are a common trauma, affecting 1% of the Australian population annually and are associated with significant physical, psychological, social and economic burdens for victims and their families. There has been a recent paradigm shift from the treatment of burns to a more preventative approach. ObjectivesTo examine the risk of severe burns by geographic region in New South Wales (NSW), Australia, using geospatial analytic techniques. MethodRetrospective analyses were carried out to examine the 2006–2010 NSW burns data collected by the NSW Severe Burns Injury Service. Spatial analysis software was used to map the relative risk of burns by postcode areas. Spatial cluster analyses were then undertaken for the Greater Sydney Area (GSA) using Global Moran's I statistics and Getis-Ord analyses. High- and low-risk populations and areas were examined to ascertain differences by sociodemographic characteristics, etiology and the extent of burn. ResultsScalds were the most common types of burns and men were at greater risk of burns than women. There was significant clustering of burns by postcode area, with a higher relative risk of severe burns seen in Western Sydney area and lower risk observed in Eastern and Southern Sydney. In high-risk areas burns occurred more frequently in the 13–24 months and the 20–29 years age groups, while in low-risk areas burns mostly affect the 20–29 and 30–39 years age groups. High-risk areas were characterized by socioeconomic disadvantage. ImplicationsMapping the risk of burns is a valuable tool for policy makers to plan and deliver targeted intervention strategies for burns prevention.

Suboptimal Omega-3 Levels in Australian Adolescents

Objective: To quantitate the omega-3 status in a cohort of Australian adolescents. Design, Setting and Participants: A cross-sectional descriptive study of 251 apparently healthy adolescents (192 female, 59 male) aged 15-17 years, in year 11, from 10 schools within the Northern Sydney and Central Coast areas of New South Wales. Participants provided a morning non-fasting blood sample via finger-prick and written answers to specific demographic and lifestyle questions. Omega-3 index was calculated by adding %EPA and %DHA values in the whole blood. Equivalent erythrocyte omega-3 index values were obtained by using conversion factors (1.33 for EPA and 2.22 for DHA) from published erythrocyte/whole blood values. Main Outcome Measures: Quantitation of the individual, and estimation of the group average, blood omega-3 Index. Results: The blood omega-3 Index for this adolescent cohort ranged from 2.1-22.3 with a mean of 8.3±3.2, and median of 7.8. On average males had a higher omega-3 Index compared to females (10.5±3.7 vs 7.7±2.6, p&lt;0.001). Fifty three percent of adolescents tested had an omega-3 Index below the optimum of &gt;8. Three percent had an Index of &lt;4, placing them in the high risk category for disease. On average, adolescents from low or medium socioeconomic communities had a significantly lower omega-3 Index compared to those from higher socioeconomic neighbourhoods (mean difference=1.4, p=0.018). Overall 20% of boys and 17% of girls reported regularly taking omega-3 supplements. Regular use of omega-3 supplements was associated with a higher average omega-3 Index (9.8±3.7, n=44 compared to 8.0±3.0, n=203, p=0.001 in those not taking supplements). Conclusion: This study indicates that Australian adolescents, even when from advantaged homes, have a high probability of below optimum omega-3 levels. As reduced omega-3 levels are linked to conditions of public health concern such as diabetes, asthma and depression, targeted strategies to improve the omega-3 status in the childhood population may be warranted.

Circumscription and phylogenetic relationship of Prostanthera densa and P. marifolia (Lamiaceae)

Prostanthera densa A.A.Ham. and P. marifolia R.Br. (Lamiaceae) are endemic species with restricted distributions within the near-coastal regions of New South Wales (Australia). Prostanthera marifolia was previously presumed extinct, but is now known from a small population in the Manly-Warringah area of metropolitan Sydney, and is morphologically very similar to P. densa. Prostanthera densa is known from five disjunct populations, distributed from Port Stephens (in the north) to Jervis Bay (in the south). The sequence variation of two chloroplast spacer regions, trnT-trnL and psbA-trnH, and the external transcribed spacer (ETS) region of nuclear ribosomal DNA were analysed to evaluate the phylogenetic relationship and taxonomic integrity of these species. Although trnT-trnL data were uninformative, trees generated from psbA-trnH data provided support for recognising P. marifolia as a distinct species sister to P. densa. A multivariate evaluation of the variation in morphological characters also supported the distinction of these two morphologically similar and closely related species. The ETS data indicated that each of the disjunct populations of P. densa were genetically isolated. Since there was no gene flow between populations of P. densa, it was concluded that the conservation of this species requires all populations to be protected.

Neuroangiostrongyliasis due to Angiostrongylus cantonensis in gang‐gang cockatoos (Callocephalon fimbriatum)

Four gang-gang cockatoos from an aviary in Sydney displayed severe neurological signs. Three were necropsied and histopathology of the brains and spinal cords revealed migrating nematodes, which were identified as Angiostrongylus cantonensis. The migrating larval nematodes created tracts of malacia in the brain, but elicited little inflammatory cell infiltration. However, adult nematodes that had emerged onto the meningeal surface of the spinal cord evoked a marked non-suppurative reaction. Detailed histological examination of other tissues revealed larvae embedded in arterioles in the gastrointestinal serosa, lung and heart, which were associated with a significant granulomatous response. The latter lesions were consistent with our understanding of the pathogenesis of infection with this parasite, but have not been previously described, probably as a result of limited sampling. Angiostrongylus cantonensis is still present in the Sydney area and can cause significant disease in exposed animals, including birds. It also highlights potential human health problems.

Evaluating the transport, health and economic impacts of new urban cycling infrastructure in Sydney, Australia – protocol paper

BackgroundThere are repeated calls to build better cycling paths in Australian cities if the proportion of people cycling is to increase. Yet the full range of transport, health, environmental and economic impacts of new cycling infrastructure and the extent to which observed changes are sustained is not well understood. The City of Sydney is currently building a new bicycle network, which includes a new bicycle path separated from road traffic in the south Sydney area. This protocol paper describes a comprehensive method to evaluate this new cycling infrastructure.MethodA cohort of residents within two kilometres of the new bicycle path will be surveyed at baseline before a new section of bicycle path is built, and again 12 and 24 months later to assess changes in travel behaviour, sense of community, quality of life and health behaviours. Residents in a comparable area of Sydney that will not get a new separated bike path will act as a comparison group. At baseline a sub-set of residents who volunteer will also take a small GPS device with them for one week to assess travel behaviour.DiscussionThis research should contribute to the advancement in evaluation and appraisal methods for cycling projects.

The Resilience Complex

The Resilience Complex

Influence of population versus convenience sampling on sample characteristics in studies of cognitive aging

PurposeWe examined whether differences in findings of studies examining mild cognitive impairment (MCI) were associated with recruitment methods by comparing sample characteristics in two contemporaneous Australian studies, using population-based and convenience sampling. MethodThe Sydney Memory and Aging Study invited participants randomly from the electoral roll in defined geographic areas in Sydney. The Australian Imaging, Biomarkers and Lifestyle Study of Ageing recruited cognitively normal (CN) individuals via media appeals and MCI participants via referrals from clinicians in Melbourne and Perth. Demographic and cognitive variables were harmonized, and similar diagnostic criteria were applied to both samples retrospectively. ResultsCN participants recruited via convenience sampling were younger, better educated, more likely to be married and have a family history of dementia, and performed better cognitively than those recruited via population-based sampling. MCI participants recruited via population-based sampling had better memory performance and were less likely to carry the apolipoprotein E ε4 allele than clinically referred participants but did not differ on other demographic variables. ConclusionA convenience sample of normal controls is likely to be younger and better functioning and that of an MCI group likely to perform worse than a purportedly random sample. Sampling bias should be considered when interpreting findings.

Environmentally driven technical innovation by Australian construction SMEs

Purpose – The purpose of this paper is to investigate whether technical innovations by construction industry small and medium-sized enterprises (SMEs) with an environmental focus, require any specific circumstances for successful marketplace delivery. Design/methodology/approach – A value tree of significant factors was developed from a literature review. This was tested by a survey of established technical innovators within SMEs in the area of Sydney and environs, using analytic hierarchy process methodology. Findings – The regulatory environment was demonstrated to be much more important to environmental innovators than to others. Conversely the influence of clients and end users was less significant for the environmentally focused innovators. Research limitations/implications – The sample size was necessarily small because the subjects were all peer recognised technical innovators. Analysis of variance was used to identify significant differences between environmentally focused and other innovations among the survey respondents. Social implications – Performance-based standards were seen to be significant enablers for environmentally focused innovation delivery. A degree of flexibility in building regulations may be crucial to innovation delivery by SMEs. Originality/value – The paper stresses the importance for regulators of reaching an understanding of the restrictions that prescriptive standards may put of those seeking to improve the environmental performance of the construction industry.

Why sustainable and ‘nutritionally correct’ food is not on the agenda: Western Sydney, the moral arts of everyday life and public policy

Within a context of delivering food security into the future, dietary guidelines are being reframed, corporations are replacing unsustainable products, and consumers are being encouraged to become ecological citizens. While there is a growing literature on the food practices of ‘alternative’ consumers, ‘mainstream’ consumers are less well understood. This paper describes qualitative research undertaken in a socio-economically disadvantaged area of Sydney, Australia, which aimed to uncover consumer views towards sustainable and healthy diets. Most participants indicated a discrepancy between their desired and actual behaviours: while they want to support Australian, or local, food producers they gravitate towards cheap and tasty food from ‘anywhere’; and while they associate nutritious food with fresh food, they will buy processed foods which can be less expensive, appeal to children and are prone to less waste. Reflecting mainstream Australian political culture, participants were compromising household food budgets in order to pursue a socially acceptable standard of living (including decent housing, car-reliance). They were also incorporating the pleasure and desires of family members as part of ‘the moral arts of everyday life’. Using social theories of consumption and practice sociology we argue that food choices and practices – easy or not – need to be interpreted as part of the role that consumption plays in political citizenship and moral subjectivity. In the Western Sydney context, food practices are essentially household budget and family nourishment practices rather than nutrition and sustainability practices; a position which is not addressed in the government’s new food policies or wage determination processes.

Parenting style and dietary behaviour of young children. Findings from the Healthy Beginnings Trial

Parenting style may have a role in the development of young children’s dietary behaviour, and a better understanding of parenting style may lead to better-targeted childhood obesity prevention interventions. This study aimed to investigate the association of parental self-efficacy, parenting style and dietary behaviour of young children. A cross-sectional study with 242 first-time mothers and their children was conducted using the data from the Healthy Beginnings Trial undertaken in one of the most socially and economically disadvantaged areas of south-western Sydney, in 2007–2010. Parental self-efficacy, parenting style (warmth and hostility) and children’s dietary behaviours (consumption of vegetables, fruit, soft-drink and snacks) were assessed by face-to-face interviews with participating mothers in the control group when their children were 2years old. Logistic regression analysis was conducted to examine the association between parenting style and the child’s dietary behaviour. Mothers with higher levels of global parental self-efficacy and self-efficacy for an infant were more likely to report their children had 2 serves of vegetables per day, with odds ratio (OR) 2.40 (95%CI 1.35–4.27, P=0.003) and OR 1.88 (95%CI 1.06–3.36, P=0.03), respectively. A higher level of global parental self-efficacy or self-efficacy for an infant was significantly associated with having 2 serves of fruit per day with adjusted odds ratio (AOR) 2.46 (95%CI 1.35–4.48, P=0.003) and AOR 1.85 (95%CI 1.00–3.41, P=0.048), respectively, after adjusting for annual household income. Mothers with a higher level of parental warmth were more likely to report their children had 2 serves of vegetable per day with OR 1.85 (95%CI 1.06–3.25, P=0.03). Parental self-efficacy and parenting style were associated, cross-sectionally, with important children’s dietary behaviours. Interventions which target parental self-efficacy and parenting style may improve eating habits of young children, and contribute to childhood obesity prevention.