Study of new particle formation in subtropical urban environment in Brisbane, Australia

Atmospheric ultrafine particles play an important role in affecting human health, altering climate and degrading visibility. Numerous studies have been conducted to better understand the formation process of these particles, including field measurements, laboratory chamber studies and mathematical modeling approaches. Field studies on new particle formation found that formation processes were significantly affected by atmospheric conditions, such as the availability of particle precursors and meteorological conditions. However, those studies were mainly carried out in rural areas of the northern hemisphere and information on new particle formation in urban areas, especially those in subtropical regions, is limited. In general, subtropical regions display a higher level of solar radiation, along with stronger photochemical reactivity, than those regions investigated in previous studies. However, based on the results of these studies, the mechanisms involved in the new particle formation process remain unclear, particularly in the Southern Hemisphere. Therefore, in order to fill this gap in knowledge, a new particle formation study was conducted in a subtropical urban area in the Southern Hemisphere during 2009, which measured particle size distribution in different locations in Brisbane, Australia. Characterisation of nucleation events was conducted at the campus building of the Queensland University of Technology (QUT), located in an urban area of Brisbane. Overall, the annual average number concentrations of ultrafine, Aitken and nucleation mode particles were found to be 9.3 x 103, 3.7 x 103 and 5.6 x 103 cm-3, respectively. This was comparable to levels measured in urban areas of northern Europe, but lower than those from polluted urban areas such as the Yangtze River Delta, China and Huelva and Santa Cruz de Tenerife, Spain. Average particle number concentration (PNC) in the Brisbane region did not show significant seasonal variation, however a relatively large variation was observed during the warmer season. Diurnal variation of Aitken and nucleation mode particles displayed different patterns, which suggested that direct vehicle exhaust emissions were a major contributor of Aitken mode particles, while nucleation mode particles originated from vehicle exhaust emissions in the morning and photochemical production at around noon. A total of 65 nucleation events were observed during 2009, in which 40 events were classified as nucleation growth events and the remainder were nucleation burst events. An interesting observation in this study was that all nucleation growth events were associated with vehicle exhaust emission plumes, while the nucleation burst events were associated with industrial emission plumes from an industrial area. The average particle growth rate for nucleation events was found to be 4.6 nm hr-1 (ranging from 1.79-7.78 nm hr-1), which is comparable to other urban studies conducted in the United States, while monthly particle growth rates were found to be positively related to monthly solar radiation (r = 0.76, p <0.05). The particle growth rate values reported in this work are the first of their kind to be reported for the subtropical urban area of Australia. Furthermore, the influence of nucleation events on PNC within the urban airshed was also investigated. PNC was simultaneously measured at urban (QUT), roadside (Woolloongabba) and semi-urban (Rocklea) sites in Brisbane during 2009. Total PNC at these sites was found to be significantly affected by regional nucleation events. The relative fractions of PNC to total daily PNC observed at QUT, Woolloongabba and Rocklea were found to be 12%, 9% and 14%, respectively, during regional nucleation events. These values were higher than those observed as a result of vehicle exhaust emissions during weekday mornings, which ranged from 5.1-5.5% at QUT and Woolloongabba. In addition, PNC in the semi-urban area of Rocklea increased by a factor of 15.4 when it was upwind from urban pollution sources under the influence of nucleation burst events. Finally, we investigated the influence of sulfuric acid on new particle formation in the study region. A H2SO4 proxy was calculated by using [SO2], solar radiation and particle condensation sink data to represent the new particle production strength for the urban, roadside and semi-urban areas of Brisbane during the period June-July of 2009. The temporal variations of the H2SO4 proxies and the nucleation mode particle concentration were found to be in phase during nucleation events in the urban and roadside areas. In contrast, the peak of proxy concentration occurred 1-2 hr prior to the observed peak in nucleation mode particle concentration at the downwind semi-urban area of Brisbane. A moderate to strong linear relationship was found between the proxy and the freshly formed particles, with r2 values of 0.26-0.77 during the nucleation events. In addition, the log[H2SO4 proxy] required to produce new particles was found to be ~1.0 ppb Wm-2 s and below 0.5 ppb Wm-2 s for the urban and semi-urban areas, respectively. The particle growth rates were similar during nucleation events at the three study locations, with an average value of 2.7 ± 0.5 nm hr-1. This result suggested that a similar nucleation mechanism dominated in the study region, which was strongly related to sulphuric acid concentration, however the relationship between the proxy and PNC was poor in the semi-urban area of Rocklea. This can be explained by the fact that the nucleation process was initiated upwind of the site and the resultant particles were transported via the wind to Rocklea. This explanation is also supported by the higher geometric mean diameter value observed for particles during the nucleation event and the time lag relationship between the H2SO4 proxy and PNC observed at Rocklea. In summary, particle size distribution was continuously measured in a subtropical urban area of southern hemisphere during 2009, the findings from which formed the first particle size distribution dataset in the study region. The characteristics of nucleation events in the Brisbane region were quantified and the properties of the nucleation growth and burst events are discussed in detail using a case studies approach. To further investigate the influence of nucleation events on PNC in the study region, PNC was simultaneously measured at three locations to examine the spatial variation of PNC during the regional nucleation events. In addition, the impact of upwind urban pollution on the downwind semi-urban area was quantified during these nucleation events. Sulphuric acid was found to be an important factor influencing new particle formation in the urban and roadside areas of the study region, however, a direct relationship with nucleation events at the semi-urban site was not observed. This study provided an overview of new particle formation in the Brisbane region, and its influence on PNC in the surrounding area. The findings of this work are the first of their kind for an urban area in the southern hemisphere.

Characterisation of atmospheric deposited particles during a dust storm in urban areas of Eastern Australia

The characteristics of dust particles deposited during the 2009 dust storm in the Gold Coast and Brisbane regions of Australia are discussed in this paper. The study outcomes provide important knowledge in relation to the potential impacts of dust storm related pollution on ecosystem health in the context that the frequency of dust storms is predicted to increase due to anthropogenic desert surface modifications and climate change impacts. The investigated dust storm contributed a large fraction of fine particles to the environment with an increased amount of total suspended solids, compared to dry deposition under ambient conditions. Although the dust storm passed over forested areas, the organic carbon content in the dust was relatively low. The primary metals present in the dust storm deposition were aluminium, iron and manganese, which are common soil minerals in Australia. The dust storm deposition did not contain significant loads of nickel, cadmium, copper and lead, which are commonly present in the urban environment. Furthermore, the comparison between the ambient and dust storm chromium and zinc loads suggested that these metals were contributed to the dust storm by local anthropogenic sources. The potential ecosystem health impacts of the 2009 dust storm include, increased fine solids deposition on ground surfaces resulting in an enhanced capacity to adsorb toxic pollutants as well as increased aluminium, iron and manganese loads. In contrast, the ecosystem health impacts related to organic carbon and other metals from dust storm atmospheric deposition are not considered to be significant.

Improving the Walkability of Subtropical Urban Areas: a case study analysis for the development of a design process

This research develops a new framework to be used as a tool for analysing and designing walkable communities. The literature review recognises the work of other researchers combining their findings with the theory of activity nodes and considers how a framework may be used on a more global basis. The methodology develops a set of criteria through the analysis of noted successful case studies and this is then tested against an area with very low walking rates in Brisbane, Australia. Results of the study suggest that as well as the accepted criteria of connectivity, accessibility, safety, security, and path quality further criteria in the form or planning hierarchy, activity nodes and climate mitigation could be added to allow the framework to cover a broader context. Of particular note is the development of the nodal approach, which allows simple and effective analysis of existing conditions, and may also prove effective as a tool for planning and design of walkable communities.

Review : "Heat islands : understanding and mitigating heat in urban areas" by Lisa Gartland. Reviewed by Tony Matthews.

Heat islands are a significant problem in urban spaces worldwide. The phenomenon occurs when air and surface temperatures in urban areas significantly exceed those experienced in nearby rural areas. There are two main causes of heat islands. The first is the use of highly absorptive construction materials in buildings and infrastructure, which soak up heat and radiate it back into the immediate surroundings. These materials, including but not limited to concrete, steel, asphalt and stone, are usually impermeable and so do not embody moisture that could dissipate some of the absorbed heat. The second cause relates to urban form, where the canyon-like configurations of buildings and streets channel and trap heat from the sun. In both cases, an absence of greenery and other soft landscaping can compound the problem by lowering capacity for cooling through shading and evotranspiration. Incidences of heat islands increase as urban areas swell in size and cover more land area, making the phenomenon an unwelcome side effect of global trends towards increased urbanisation. Heat islands create serious problems, including increased energy demand for cooling, declining air quality and heat stress for people and animals. In very severe cases, heat islands can compound the effects of high urban temperatures, leading to increased human mortality...

Sleepy driving and pulling over for a rest : investigating individual factors that contribute to these driving behaviours

Driver sleepiness is a substantial crash risk factor and as such, is a major contributor to crash statistics. A number of individual factors (i.e., psychological factors) have been suggested to influence driving while sleepy. However, few studies have examined the influence of these individual factors for sleepy driving in combination. The current study sought to examine how various demographic factors, attitudes, perceived legitimacy, personality constructs, and risk taking variables were associated with self-reported likelihood of driving sleepy and pulling over and resting when sleepy. The results show that being a younger driver, having positive attitudes towards driving sleepy, and high levels of emotional stability were related to self-reported likelihood of driving sleepy. Whereas, being an older driver and having negative attitudes towards driving sleepy were associated with self-reported likelihood of pulling over and resting when sleepy. Overall, the obtained results suggest that the age and attitudes of the driver have greater influence than personality traits or risk taking factors. Campaigns focused on changing attitudes to reflect the dangerousness of sleepy driving could be important for road safety outcomes.

‘All in a day’s work’ : the lifeworld of older people in New Zealand rest homes

This doctoral thesis contributes to critical gerontology research by investigating the lived experiences of residents in the everyday world of New Zealand rest homes. There is a need to understand how frail rest home residents experience "age". This study focuses on describing and understanding residents lived experiences. As the New Zealand population is ageing, this phenomenological focus adds clarity to the poorly understood lived experiences about being aged in rest homes. Policy initiatives such as the Positive Ageing Strategy with its emphasis on keeping older people living in the community largely ignore the life practices of the increasing proportions of frail older people who require long-term residential care. My mixed-methods modified framework approach draws on the lifeworld as understood by Max van Manen (1990) and Alfred Schütz (1972). The lifeworld is made up of thematic strands of lived experience: these being lived space, lived time, lived body and lived relations with others, which are both the source and object of phenomenological research (van Manen, 1990). These strands are temporarily unravelled and considered in-depth for 27 residents who took part in audio-recorded interviews, before being interwoven through a multiple-helix model, into an integrated interpretation of the residents‟ lifeworld. Supplementing and backgrounding the interviews with these residents, are descriptive data including written interview summaries and survey findings about the relationships and pastimes of 352 residents living in 21 rest homes, which are counted and described. The residents day-to-day use of rest home space, mediated temporal order, self-managed bodies and minds, and negotiated relationships are interpreted. The mythology of the misery of rest home life is challenged, and a more constructive critical gerontology approach is offered. Findings of this research reveal how meanings around daily work practices are constructed by the residents. These elders participate in daily rest home life, from the sidelines or not at all, as they choose or are able, and this always involves work for the residents. They continue to actively manage satisfactory and fulfilling pastimes and relationships, because in their ordinary, everyday lifeworld it is “all in a day‟s work”.

Postnatal depression in Central Vietnam

Postnatal depression (PND) is a significant global health issue, which not only impacts maternal wellbeing, but also infant development and family structures. Mental health disorders represent approximately 14% of global burden of disease and disability, including low and middle-income countries (LMIC), and PND has direct relevance to the Millennium Development Goals of reducing child mortality, improving maternal health, and creating global partnerships (United Nations, 2012; Guiseppe, Becker & Farmer, 2011). Emerging evidence suggests that PND in LMIC is similar to, or higher than in high-income countries (HIC), however, less than 10% of LMIC have prevalence data available (Fisher, Cabral de Mello, & Izutsu 2009; Lund et al., 2011). Whilst a small number of studies on maternal mental disorders have been published in Vietnam, only one specifically focuses on PND in a hospital-based sample. Also, community based mental health studies and information on mental health in rural areas of Vietnam is still scarce. The purpose of this study was to determine the prevalence of PND, and its associated social determinants in postnatal women in Thua Thien Hue Province, Central Vietnam. In order to identify social determinants relevant to the Central Vietnamese context, two qualitative studies and one community survey were undertaken. Associations between maternal mental health and infant health outcomes were also explored. The study was comprised of three phases. Firstly, iterative, qualitative interviews with Vietnamese health professionals (n = 17) and postpartum women (n = 15) were conducted and analysed using Kleinman's theory of explanatory models to identify narratives surrounding PND in the Vietnamese context (Kleinman, 1978). Secondly, a participatory concept mapping exercise was undertaken with two groups of health professionals (n = 12) to explore perceived risk and protective factors for postnatal mental health. Qualitative phases of the research elucidated narratives surrounding maternal mental health in the Vietnamese context such as son preference, use of traditional medicines, and the popularity of confinement practices such as having one to three months of complete rest. The qualitative research also revealed the construct of depression was not widely recognised. Rather, postpartum changes in mood were conceptualised as a loss of 'vital strength' following childbirth or 'disappointment'. Most women managed postpartum changes in mood within the family although some sought help from traditional medicine practitioners or biomedical doctors. Thirdly, a cross-sectional study of twelve randomly selected communes (six urban, six rural) in Thua Thien Hue Province was then conducted. Overall, 465 women with infants between 4 weeks and six months old participated, and 431 questionnaires were analysed. Women from urban (n = 216) and rural (n = 215) areas participated. All eligible women completed a structured interview about their health, basic demographics, and social circumstances. Maternal depression was measured using the Edinburgh Postnatal Depression Scale (EPDS) as a continuous variable. Multivariate generalised linear regression was conducted using PASW Statistics version 18.0 (2009). When using the conventional EPDS threshold for probable depression (EPDS score ~ 13) 18.1% (n = 78) of women were depressed (Gibson, McKenzie-McHarg, Shakespeare, Price & Gray, 2009). Interestingly, 20.4% of urban women (n = 44) had EPDS scores~ 13, which was a higher proportion than rural women, where 15.8% (n = 34) had EPDS scores ~ 13, although this difference was not statistically significant: t(429) = -0.689, p = 0.491. Whilst qualitative narratives identified infant gender and family composition, and traditional confinement practices as relevant to postnatal mood, these were not statistically significant in multivariate analysis. Rather, poverty, food security, being frightened of your husband or family members, experiences of intimate partner violence and breastfeeding difficulties had strong statistical associations. PND was also associated with having an infant with diarrhoea in the past two weeks, but not infant malnutrition or acute respiratory infections. This study is the first to explore maternal mental health in Central Vietnam, and provides further evidence that PND is a universally experienced phenomenon. The independent social risk factors of depressive symptoms identified such as poverty, food insecurity, experiences of violence and powerlessness, and relationship adversity points to women in a context of social suffering which is relevant throughout the world (Kleinman, Das & Lock, 1997). The culturally specific risk factors explored such as infant gender were not statistically significant when included in a multivariable model. However, they feature prominently in qualitative narratives surrounding PND in Vietnam, both in this study and previous literature. It appears that whilst infant gender may not be associated with PND per se, the reactions of close relatives to the gender of the baby can adversely affect maternal wellbeing. This study used a community based participatory research approach (CBPR) (Israel.2005). This approach encourages the knowledge produced to be used for public health interventions and workforce training in the community in which the research was conducted, and such work has commenced. These results suggest that packages of interventions for LMIC devised to address maternal mental health and infant wellbeing could be applied in Central Vietnam. Such interventions could include training lay workers to follow up postpartum women, and incorporating mental health screening and referral into primary maternal and child health care (Pate! et al., 2011; Rahman, Malik, Sikander & Roberts, 2008). Addressing the underlying social determinants of PND through poverty reduction and violence elimination programs is also recommended.

Context matters : Violence against women and reporting to police in rural, suburban and urban areas

Despite plentiful efforts to identify perpetrator, victim, and incident characteristics correlated with reporting violence against women to police, few studies have addressed the contexts that shape such reporting. Even fewer have examined variations in these contexts across geographic areas. Drawing upon National Crime Victimization Survey data from 1992 through 2009, this paper uses conjunctive analysis of case configurations to identify and investigate the dominant situational contexts of reporting of violence against women to police across rural, suburban, and urban areas. Our findings show that context matters and the importance of incident, perpetrator, and victim characteristics vary across geographic areas.

Towards an appropriate fatigue loading sequence for roof claddings in cyclone prone areas

Currently two different fatigue tests are being used to investigate the fatigue susceptibility of roof claddings in the cyclone prone areas of Australia. In order to resolve this issue a detailed investigation was conducted to study the nature of cyclonic wind forces using wind tunnel testing and computer modelling and the fatigue behaviour of metal roof claddings using structural testing. This led to the development of an accurate, but complicated loading matrix for a design cyclone. Based on this matrix, a simplified low-high-low loading sequence has been developed for the testing of roofing systems in cyclone prone areas. This paper first reviews the currently used fatigue loading sequences, then presents details of the cyclonic wind loading matrix and finally the development of the new simplified loading sequence. This simplified sequence should become the only suitable test for most of the cyclone prone areas of Australia covered by Region C which suffers from Category 4 cyclones. For Region D which suffers from Category 5 cyclones, the same loading sequence with 20% increased cycles has been recommended. An experimental programme to validate the new simplified loading sequence has been proposed.

A review of the educational needs of nurses administering cancer chemotherapy in rural and remote areas of Queensland

This paper describes current issues in chemotherapy nursing practice in rural and remote Australia. There is a trend to refer chemotherapy clients back to their rural and remote health facility for treatment from major oncology centres in Australia. However, it is increasingly apparent that the majority of nurses administering chemotherapy in smaller centres lack the theoretical and clinical knowledge to ensure optimum client outcomes and nurse/client safety. There are also issues unique to rural and remote life which will influence optimum chemotherapy service delivery. The research program described in the paper will ascertain the education requirements of rural and remote nurses administering chemotherapy and the design and delivery of a chemotherapy education package specific to the rural and remote context. Similar programs will ensure the best standards of chemotherapy practice in non-metropolitan areas by enhancing the practical and theoretical knowledge base of rural and remote nurses.

The safety profile of perflutren microsphere contrast echocardiography during rest and stress imaging : results from an Australian multicentre cohort

Background Contrast enhanced echocardiography (CEE) is utilised when sub-optimal image quality results in non-diagnostic echocardiograms. However, there have been numerous safety notices issued by regulatory authorities regarding rare but potentially serious adverse reactions (AR). This multi-centre, retrospective analysis was performed to assess the short-term safety of CEE in a broad range of indications. Methods All CEE performed over 58 months at three institutions were assessed for AR within 30 min. Results A total of 5956 CEE were performed in 5576 patients. A total of 4903 were stress CEE and 1053 resting CCE.Bolus administration in 5719, infusion in 237 cases; 89.9% of CCE were outpatients. Commonest CEE indication was functional stress testing (82.3%). There were 16 AR related to CEE (0.27%). All AR were mild, transient and all patients made a full recovery. No cases of serious anaphylaxis or death within 30 min of contrast administration. Comparing those with and without an AR, there were no significant differences in age, gender, BMI, LVEF, patient location, exam type or RVSP. There was a slightly increased likelihood of an AR during infusion versus bolus dosing (p = 0.02). Conclusion CEE is a safe investigation in a broad range of indications and clinical scenarios. AR are very rare, mild and transient.