997 resultados para Botany - Australia
Resumo:
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.
Resumo:
The relationship between social background and achievement has preoccupied educational researchers since the mid-20th century with major studies in the area reaching prominence in the late 60s. Despite five decades of research and innovation since, recent studies using OECD data have shown that the relationship is strengthening rather than weakening. In this paper, the systematic destabilisation of public education in Australia is examined as a philosophical problem stemming from a fundamental shift in political orientation, where “choice” and “aspiration” work to promote and disguise survivalism. The problem for education however extends far deeper than the inequity in Federal government funding. Whilst this is a major problem, critical scrutiny must also focus on what states can do to turn back aspects of their own education policy that work to exacerbate and entrench social disadvantage.
Resumo:
The past four decades have seen increasing public and professional awareness of child sexual abuse. Congruent with public health approaches to prevention, efforts to eliminate child sexual abuse have inspired the emergence of prevention initiatives which can be provided to all children as part of their standard school curriculum. However, relatively little is known about the scope and nature of child sexual abuse prevention efforts in government school systems internationally. This paper assesses and compares the policies and curriculum initiatives for child sexual abuse prevention education in primary (elementary) schools across state and territory Departments of Education in Australia. Using publicly available electronic data, a deductive qualitative content analysis of policy and curriculum documents was undertaken to examine the characteristics of child sexual abuse prevention education in these school systems. It was found that the system-level provision of child sexual abuse prevention education occurs unevenly across state and territory jurisdictions. This results in the potential for substantial inequity in Australian children’s access to learning opportunities in child abuse prevention education as a part of their standard school curriculum. In this research, we have developed a strategy for generating a set of theoretically-sound empirical criteria that may be more extensively applied in comparative research about prevention initiatives internationally.
Resumo:
The 2011 floods in Southeast Queensland had a devastating impact on many sectors including transport. Road and rail systems across all flooded areas of Queensland were severely affected and significant economic losses occurred as a result of roadway and railway closures. Travellers were compelled to take alternative routes because of road closures or deteriorated traffic conditions on their regular route. Extreme changes in traffic volume can occur under such scenarios which disrupts the network re-equilibrium and re-stabilisation in the recovery phase as travellers continuously adjust their travel options. This study explores how travellers respond to such a major network disruption. A comprehensive study was undertaken focusing on how bus riders reacted to the floods in Southeast Queensland by comparing the ridership patterns before, during and after the floods. The study outcomes revealed the evolving reactions of transit users to direct and indirect impacts of a natural disaster. A good understanding of this process is crucial for developing appropriate strategies to encourage modal shift of automobile users to public transit and also for modelling of travel behaviours during and after a major network disruption caused by natural disasters.
Resumo:
The International Road Assessment Program (iRAP) is a not-for-profit organisation that works in partnership with governments and non-government organisations in all parts of the world to make roads safe. The iRAP Malaysia pilot study on 3,700km of road identified the potential to save 31,800 deaths and serious injuries over the next 20 years from proven engineering improvements. To help ensure the iRAP data and results are available to planners and engineers, iRAP, together with staff from the Centre for Accident Research and Road Safety – Queensland (CARRS-Q) and the Malaysian Institute of Road Safety Research (MIROS) developed a 5-day iRAP training course that covers the background, theory and practical application of iRAP protocols, with a special focus on Malaysian case studies. Funding was provided by a competitive grant from the Australian-Malaysia Institute.
Resumo:
Objectives: Little is known about young adult women's experience of unintended pregnancy in Australia, nor the extent to which ineffective contraceptive use or contraceptive failure may lead to young women becoming pregnant. The CUPID study is the first in Australia to examine young adult Australian women's patterns of contraceptive use, their experience of unintended pregnancy, and their use (or not) of contraception at the time of conception. Methods: Australian women aged 18-23 years completed an online survey about contraceptive use and experience of unintended pregnancy. They were recruited through a range of methods including advertising on Facebook, and snowball sampling. Sample representativeness was established through comparison with Census data. Results: Of the 511 respondents, 403 women reported that they had ever had sex and were not currently pregnant. Among these women, the pill was the most common method of contraception used on the most recent occasion, used alone (30%) or with condoms (21%). Condoms (alone or with another method other than the pill) were used by a further 17%, and long-acting contraceptive methods by a further 16%. Other methods such as natural methods or partner vasectomy were used by 16%. The withdrawal method was surprisingly common and was mentioned by 15% of the women overall, usually in combination with another method. There were 63 women who had been pregnant, including 5 who were pregnant at the time of the survey, and of these 55 (87%) had become pregnant by accident. Of these 55 women, 69% reported using a range of contraception methods when they became pregnant by accident: Pill only (29%) and in combination with condoms (3%) and withdrawal (5%); condoms only (18%) and in combination with withdrawal (16%); emergency contraceptive pill only (3%) and in combination with withdrawal (3%) and withdrawal only (24%). Conclusions: This study highlighted the use of less effective methods of contraception among young Australian women. The withdrawal method was commonly used, often in combination with other methods, particularly before an unintended pregnancy. Among the women who had been pregnant, most reported that their pregnancy had been unintended. A third of the young women who had experienced an unintended pregnancy were using the withdrawal method. Further research is needed about the place of the withdrawal method in the contraceptive practices of young women.
Resumo:
Media and Information Literacy is the focus of several teaching and research projects at Queensland University of Technology and there is particular emphasis placed on digital technologies and how they are used for communication, information use and learning in formal contexts such as schools. Research projects are currently taking place in several locations where investigators are collecting data on approaches to the use of digital media tools like cameras and editing systems, tablet computers and video games. This complements QUT’s teacher preparation courses, including preparation to implement UNESCO’s Online Course in Media and Information Literacy and Intercultural Dialogue in 2013. This work takes place in the context of projects occurring at the National level in Australia that continue to promote Media and Information Literacy.