Formation mechanisms of secondary organic aerosols in relation to laser printer emissions

Due to their large surface area, complex chemical composition and high alveolar deposition rate, ultrafine particles (UFPs) (< 0.1 ìm) pose a significant risk to human health and their toxicological effects have been acknowledged by the World Health Organisation. Since people spend most of their time indoors, there is a growing concern about the UFPs present in some indoor environments. Recent studies have shown that office machines, in particular laser printers, are a significant indoor source of UFPs. The majority of printer-generated UFPs are organic carbon and it is unlikely that these particles are emitted directly from the printer or its supplies (such as paper and toner powder). Thus, it was hypothesised that these UFPs are secondary organic aerosols (SOA). Considering the widespread use of printers and human exposure to these particles, understanding the processes involved in particle formation is of critical importance. However, few studies have investigated the nature (e.g. volatility, hygroscopicity, composition, size distribution and mixing state) and formation mechanisms of these particles. In order to address this gap in scientific knowledge, a comprehensive study including state-of-art instrumental methods was conducted to characterise the real-time emissions from modern commercial laser printers, including particles, volatile organic compounds (VOCs) and ozone (O3). The morphology, elemental composition, volatility and hygroscopicity of generated particles were also examined. The large set of experimental results was analysed and interpreted to provide insight into: (1) Emissions profiles of laser printers: The results showed that UFPs dominated the number concentrations of generated particles, with a quasi unimodal size distribution observed for all tests. These particles were volatile, non-hygroscopic and mixed both externally and internally. Particle microanalysis indicated that semi-volatile organic compounds occupied the dominant fraction of these particles, with only trace quantities of particles containing Ca and Fe. Furthermore, almost all laser printers tested in this study emitted measurable concentrations of VOCs and O3. A positive correlation between submicron particles and O3 concentrations, as well as a contrasting negative correlation between submicron particles and total VOC concentrations were observed during printing for all tests. These results proved that UFPs generated from laser printers are mainly SOAs. (2) Sources and precursors of generated particles: In order to identify the possible particle sources, particle formation potentials of both the printer components (e.g. fuser roller and lubricant oil) and supplies (e.g. paper and toner powder) were investigated using furnace tests. The VOCs emitted during the experiments were sampled and identified to provide information about particle precursors. The results suggested that all of the tested materials had the potential to generate particles upon heating. Nine unsaturated VOCs were identified from the emissions produced by paper and toner, which may contribute to the formation of UFPs through oxidation reactions with ozone. (3) Factors influencing the particle emission: The factors influencing particle emissions were also investigated by comparing two popular laser printers, one showing particle emissions three orders of magnitude higher than the other. The effects of toner coverage, printing history, type of paper and toner, and working temperature of the fuser roller on particle number emissions were examined. The results showed that the temperature of the fuser roller was a key factor driving the emission of particles. Based on the results for 30 different types of laser printers, a systematic positive correlation was observed between temperature and particle number emissions for printers that used the same heating technology and had a similar structure and fuser material. It was also found that temperature fluctuations were associated with intense bursts of particles and therefore, they may have impact on the particle emissions. Furthermore, the results indicated that the type of paper and toner powder contributed to particle emissions, while no apparent relationship was observed between toner coverage and levels of submicron particles. (4) Mechanisms of SOA formation, growth and ageing: The overall hypothesis that UFPs are formed by reactions with the VOCs and O3 emitted from laser printers was examined. The results proved this hypothesis and suggested that O3 may also play a role in particle ageing. In addition, knowledge about the mixing state of generated particles was utilised to explore the detailed processes of particle formation for different printing scenarios, including warm-up, normal printing, and printing without toner. The results indicated that polymerisation may have occurred on the surface of the generated particles to produce thermoplastic polymers, which may account for the expandable characteristics of some particles. Furthermore, toner and other particle residues on the idling belt from previous print jobs were a very clear contributing factor in the formation of laser printer-emitted particles. In summary, this study not only improves scientific understanding of the nature of printer-generated particles, but also provides significant insight into the formation and ageing mechanisms of SOAs in the indoor environment. The outcomes will also be beneficial to governments, industry and individuals.

Study of the effectiveness of outrigger system for high-rise composite buildings for cyclonic region

The demands of taller structures are becoming imperative almost everywhere in the world in addition to the challenges of material and labor cost, project time line etc. This paper conducted a study keeping in view the challenging nature of high-rise construction with no generic rules for deflection minimizations and frequency control. The effects of cyclonic wind and provision of outriggers on 28-storey, 42-storey and 57-storey are examined in this paper and certain conclusions are made which would pave way for researchers to conduct further study in this particular area of civil engineering. The results show that plan dimensions have vital impacts on structural heights. Increase of height while keeping the plan dimensions same, leads to the reduction in the lateral rigidity. To achieve required stiffness increase of bracings sizes as well as introduction of additional lateral resisting system such as belt truss and outriggers is required.

The effectiveness of traffic policing in reducing traffic crashes

Many governments throughout the world rely heavily on traffic law enforcement programs to modify driver behaviour and enhance road safety. There are two related functions of traffic law enforcement, apprehension and deterrence, and these are achieved through three processes: the establishment of traffic laws, the policing of those laws, and the application of penalties and sanctions to offenders. Traffic policing programs can vary by visibility (overt or covert) and deployment methods (scheduled and non-scheduled), while sanctions can serve to constrain, deter or reform offending behaviour. This chapter will review the effectiveness of traffic law enforcement strategies from the perspective of a range of high-risk, illegal driving behaviours including drink/drug driving, speeding, seat belt use and red light running. Additionally, this chapter discusses how traffic police are increasingly using technology to enforce traffic laws and thus reduce crashes. The chapter concludes that effective traffic policing involves a range of both overt and covert operations and includes a mix of automatic and more traditional manual enforcement methods. It is important to increase both the perceived and actual risk of detection by ensuring that traffic law enforcement operations are sufficiently intensive, unpredictable in nature and conducted as widely as possible across the road network. A key means of maintaining the unpredictability of operations is through the random deployment of enforcement and/or the random checking of drivers. The impact of traffic enforcement is also heightened when it is supported by public education campaigns. In the future, technological improvements will allow the use of more innovative enforcement strategies. Finally, further research is needed to continue the development of traffic policing approaches and address emerging road safety issues.

Electron petrography of fine-grained matrix in the Karoonda C4 carbonaceous chondrite

The study of matrices of rare Type 4 carbonaceous chondrites can reveal important information on parent body rnetamorp~ic processes and provide a comparison with processes on parent bodies of ordinary chc-idrites. Reflectance spectra (Tholen, 1984) from the two largest asteroids in the asteroid belt, Ceres and Pallas, suggest that they may be metamorphosed carbonaceous chondrites. These two asteroids constitute - onethird of the mass in the asteroid belt implying that type 4-6 carbonaceous chondrites are poorly represented in the meteorite collection and may be of considerable importance. The matrix of the C4 chondrite Karoonda has been investigated using a JEOL 2000FX analytical electron microscope (AEM) with an attached Tracor-Northem TN5500 energy dispersive spectrometer (EDS). In previous studies (Scott and Taylor, 1985; Fitzgerald, 1979; Van Schmus, 1969), the petrography of the Karoonda matrix has been described as consisting largely of coarse-grained (50-200 urn in size) olivine and plagioclase (20-100 um in size), associated with micrometer sized magnetite and rare sulphides. AEM observations on matrix show that in addition to these large grains, there is a significant fraction (10 vol%) of interstitial fine grained phases « 5 urn). The mineralogy of these fine-grained phases differs in some respects from that of the coarser-grained matrix identified by optical and SEM techniques (Scott and Taylor, 1985; Fitzgerald, 1979; Van Schmus, 1969). I~ particular crystals of two compositionally distinct pyroxenes « 2 urn in size) have been identified which have not been previously observed in Karoonda by other analytical techniques. Thin film microanalyses (Mackinnon et al., 1986) of these two pyroxenes indicate compositions consistent with augite and low-Ca pyroxene (- Fs27). Fine-grained anhedral olivine « 2 urn size) is the most abundant phase with composition -Fa29' This composition is essentially indistinguishable from that determined for coarser-grained matrix olivines using an electron microprobe (Scott and Taylor, 1985; Fitzgerald, 1979; Van Schmus, 1969). All olivines are associated with subhedral magnetites « 1 urn size) which contain significant Cr (- 2%) and Al (- 1%) as was also noted for larger sized Karoonda magnetites by Delaney et al. (1985). It has recently been suggested (Burgess et al., 1987) on the basis of sulphur release profiles for S-isotope analyses of Karoonda that CaS04 (anhydrite) may be present. However, no sulphate phase has, as yet, been identified in the matrix of Karoonda. Low magnification contrast images suggest that Karoonda may have a significant porosity within the fine-grained matrix fraction. Most crystals are anhedral and do not show evidence for significant compaction. Individual grains often show single point contact with other grains which result in abundant intergranular voids. These voids frequently contain epoxy which was used as part of the specimen preparation procedure due to the friable nature of the bulk sample.

Mineralogy of chondritic interplanetary dust particles

From a mineralogical survey of approximately 30 chondritic micrometeorites collected from the lower stratosphere and studied in detail using current electron microscopy techniques, it is concluded that these particles represent a unique group of extraterrestrial materials. These micrometeorites differ significantly in form and texture from components of carbonaceous chondrites and contain some mineral assemblages which do not occur in any meteorite class. Electron microscope investigations of chondritic micrometeorites have established that these materials (1) are extraterrestrial in origin, (2) existed in space as small objects, (3) endured minimal alteration by planetary processes since formation, and (4) can suffer minimal pulse heating (<600°C) on entering earth's atmosphere. The probable sources for chondritic interplanetary dust particles (IDPs) are cometary and asteroidal debris and, perhaps to a lesser extent, interstellar regions. These sources have not been conclusively linked to any specific mineralogical subset of IDP, although the chondritic porous (CP) aggregate is considered of likely cometary origin. Chondritic IDPs occur in two predominant mineral assemblages: (1) carbonaceous phases and phyllosilicates and (2) carbonaceous phases and nesosilicates or inosilicates, although particles with both types of silicate assemblages are observed. Olivines, pyroxenes, layer silicates, and carbon-rich phases are the most commonly occurring minerals in many chondritic IDPs. Other phases often observed in variable proportions include sulphides, spinels, metals, metal carbides, carbonates, and minor amounts of sulphates and phosphates. Individual mineral grain sizes range from micrometers (primarily pyroxenes and olivines) to nanometers, with the predominant size for all phases less than 100 nm. Specific mineral characteristics for particular chondritic IDPs provide an indication of processes which may have occurred prior to collection in the earth's stratosphere. For example, pyroxene mineralogy in some chondritic aggregates is consistent with condensation from a vapor phase and, we consider, with condensation in a turbulent solar nebula at relatively low temperatures (<1000°C). Carbonaceous phases present in other CP aggregates have been used to imply low-temperature formation processes such as Fischer-Tropsch synthesis (∼530°C) or carbonization and graphitization (∼315°C). Alteration processes have been implicated in the formation of some layer silicates in CP aggregates and may have involved hydrocryogenic alteration at <0°C. In general, interpretations of transformation processes on submicrometer-size minerals in chondritic IDPs are consistent with formation at a radius equivalent to the asteroid belt or greater during the later stages of solar nebula evolution using currently available models.

Fatalism, superstition, religion, and culture : road user beliefs and behaviour in Pakistan

Road traffic crashes have emerged as a major health problem around the world. Road crash fatalities and injuries have been reduced significantly in developed countries, but they are still an issue in low and middle-income countries. The World Health Organization (WHO, 2009) estimates that the death toll from road crashes in low- and middle-income nations is more than 1 million people per year, or about 90% of the global road toll, even though these countries only account for 48% of the world's vehicles. Furthermore, it is estimated that approximately 265,000 people die every year in road crashes in South Asian countries and Pakistan stands out with 41,494 approximately deaths per year. Pakistan has the highest rate of fatalities per 100,000 population in the region and its road crash fatality rate of 25.3 per 100,000 population is more than three times that of Australia's. High numbers of road crashes not only cause pain and suffering to the population at large, but are also a serious drain on the country's economy, which Pakistan can ill-afford. Most studies identify human factors as the main set of contributing factors to road crashes, well ahead of road environment and vehicle factors. In developing countries especially, attention and resources are required in order to improve things such as vehicle roadworthiness and poor road infrastructure. However, attention to human factors is also critical. Human factors which contribute to crashes include high risk behaviours like speeding and drink driving, and neglect of protective behaviours such as helmet wearing and seat belt wearing. Much research has been devoted to the attitudes, beliefs and perceptions which contribute to these behaviours and omissions, in order to develop interventions aimed at increasing safer road use behaviours and thereby reducing crashes. However, less progress has been made in addressing human factors contributing to crashes in developing countries as compared to the many improvements in road environments and vehicle standards, and this is especially true of fatalistic beliefs and behaviours. This is a significant omission, since in different cultures in developing countries there are strong worldviews in which predestination persists as a central idea, i.e. that one's life (and death) and other events have been mapped out and are predetermined. Fatalism refers to a particular way in which people regard the events that occur in their lives, usually expressed as a belief that an individual does not have personal control over circumstances and that their lives are determined through a divine or powerful external agency (Hazen & Ehiri, 2006). These views are at odds with the dominant themes of modern health promotion movements, and present significant challenges for health advocates who aim to avert road crashes and diminish their consequences. The limited literature on fatalism reveals that it is not a simple concept, with religion, culture, superstition, experience, education and degree of perceived control of one's life all being implicated in accounts of fatalism. One distinction in the literature that seems promising is the distinction between empirical and theological fatalism, although there are areas of uncertainty about how well-defined the distinction between these types of fatalism is. Research into road safety in Pakistan is scarce, as is the case for other South Asian countries. From the review of the literature conducted, it is clear that the descriptions given of the different belief systems in developing countries including Pakistan are not entirely helpful for health promotion purposes and that further research is warranted on the influence of fatalism, superstition and other related beliefs in road safety. Based on the information available, a conceptual framework is developed as a means of structuring and focusing the research and analysis. The framework is focused on the influence of fatalism, superstition, religion and culture on beliefs about crashes and road user behaviour. Accordingly, this research aims to provide an understanding of the operation of fatalism and related beliefs in Pakistan to assist in the development and implementation of effective and culturally appropriate interventions. The research examines the influence of fatalism, superstition, religious and cultural beliefs on risky road use in Pakistan and is guided by three research questions: 1. What are the perceptions of road crash causation in Pakistan, in particular the role of fatalism, superstition, religious and cultural beliefs? 2. How does fatalism, superstition, and religious and cultural beliefs influence road user behaviour in Pakistan? 3. Do fatalism, superstition, and religious and cultural beliefs work as obstacles to road safety interventions in Pakistan? To address these questions, a qualitative research methodology was developed. The research focused on gathering data through individual in-depth interviewing using a semi-structured interview format. A sample of 30 participants was interviewed in Pakistan in the cities of Lahore, Rawalpindi and Islamabad. The participants included policy makers (with responsibility for traffic law), experienced police officers, religious orators, professional drivers (truck, bus and taxi) and general drivers selected through a combination of purposive, criterion and snowball sampling. The transcripts were translated from Urdu and analysed using a thematic analysis approach guided by the conceptual framework. The findings were divided into four areas: attribution of crash causation to fatalism; attribution of road crashes to beliefs about superstition and malicious acts; beliefs about road crash causation linked to popular concepts of religion; and implications for behaviour, safety and enforcement. Fatalism was almost universally evident, and expressed in a number of ways. Fate was used to rationalise fatal crashes using the argument that the people killed were destined to die that day, one way or another. Related to this was the sense of either not being fully in control of the vehicle, or not needing to take safety precautions, because crashes were predestined anyway. A variety of superstitious-based crash attributions and coping methods to deal with road crashes were also found, such as belief in the role of the evil eye in contributing to road crashes and the use of black magic by rivals or enemies as a crash cause. There were also beliefs related to popular conceptions of religion, such as the role of crashes as a test of life or a source of martyrdom. However, superstitions did not appear to be an alternative to religious beliefs. Fate appeared as the 'default attribution' for a crash when all other explanations failed to account for the incident. This pervasive belief was utilised to justify risky road use behaviour and to resist messages about preventive measures. There was a strong religious underpinning to the statement of fatalistic beliefs (this reflects popular conceptions of Islam rather than scholarly interpretations), but also an overlap with superstitious and other culturally and religious-based beliefs which have longer-standing roots in Pakistani culture. A particular issue which is explored in more detail is the way in which these beliefs and their interpretation within Pakistani society contributed to poor police reporting of crashes. The pervasive nature of fatalistic beliefs in Pakistan affects road user behaviour by supporting continued risk taking behaviour on the road, and by interfering with public health messages about behaviours which would reduce the risk of traffic crashes. The widespread influence of these beliefs on the ways that people respond to traffic crashes and the death of family members contribute to low crash reporting rates and to a system which appears difficult to change. Fate also appeared to be a major contributing factor to non-reporting of road crashes. There also appeared to be a relationship between police enforcement and (lack of) awareness of road rules. It also appears likely that beliefs can influence police work, especially in the case of road crash investigation and the development of strategies. It is anticipated that the findings could be used as a blueprint for the design of interventions aimed at influencing broad-spectrum health attitudes and practices among the communities where fatalism is prevalent. The findings have also identified aspects of beliefs that have complex social implications when designing and piloting driver intervention strategies. By understanding attitudes and behaviours related to fatalism, superstition and other related concepts, it should be possible to improve the education of general road users, such that they are less likely to attribute road crashes to chance, fate, or superstition. This study also underscores the understanding of this issue in high echelons of society (e.g., policy makers, senior police officers) as their role is vital in dispelling road users' misconceptions about the risks of road crashes. The promotion of an evidence or scientifically-based approach to road user behaviour and road safety is recommended, along with improved professional education for police and policy makers.

25 million years to break a continent : early to middle Miocene rifting and syn-extensional magmatism in the southern Gulf of California

Cenozoic extension in western Mexico has been divided into two episodes separated by the change from convergence to oblique divergence at the plate boundary. The Gulf Extensional Province is thought to have started once subduction ended at ~12.5 Ma whereas early extension is classified as Basin and Range. Mid-Miocene volcanism of the Comondú group has been considered as a subduction-related arc, whereas post ~12.5 Ma volcanism would be extension-related. Our new integration of the continental onshore and offshore geology of the south-east Gulf region, backed by tens of Ar-Ar and U-Pb ages and geochemical studies, document an early-mid Miocene rifting and extension-related bimodal to andesitic magmatism prior to subduction termination. Between ~21 and 11 Ma a system of NNW-SSE high-angle extensional faults rifted the western side of the Sierra Madre Occidental (SMO) ignimbrite plateau. In Nayarit, rhyolitic domes and some basalts were emplaced along this extensional belt at 18-17 Ma. These rocks show strong antecrystic inheritance but an absence of Mesozoic and older xenocrysts, suggesting a genesis in the mid-upper crust triggered by extension-induced basaltic influx. In Sinaloa, large grabens were floored by huge dome complexes at ~21-17 Ma and filled by continental sediments with interlayered basalts dated at 15 Ma. Mid-Miocene volcanism, including the largely volcaniclastic Comondú strata in Baja California, was thus emplaced in rift basins and appears associated to decompression melting rather than subduction. Along the coast, flat-lying basaltic lava flows dated at 11-10 Ma are exposed just above the present sea level. Here crustal thickness is 25-20 Km, almost half that in the core of the SMO, implying significant lithosphere stretching before ~11 Ma. This mafic pulse, with relatively high Ti but still clear Nb-Ta negative spikes, may be related to the detachment of the lower part of the subducted slab, allowing asthenosphere to flow into parts of the mantle previously fluxed by subduction fluids. Very uniform OIB-like lavas appear in late Pliocene and Pleistocene, only 18 m.y. after the onset of rifting and ~9 m.y. after the end of subduction. Our study shows that rifting began much earlier than Late Miocene and progressively overwhelmed subduction in generating magmatism.

Late Oligocene to middle Miocene rifting and syn-extensional magmatism in the southwestern Sierra Madre occidental, Mexico: the beginning of the Gulf of California rift

Although Basin and Range style extension affected several areas of western Mexico since the Late Eocene, extension in the Gulf of California region (the Gulf Extensional Province GEP) is thought to have started as subduction waned and ended at ~14 12.5 Ma. A general consensus also exists in considering the mid Miocene Comondú group as a suprasubduction volcanic arc. Our new integration of the geology of the south east Gulf region, backed by 43 new Ar Ar and U Pb mineral ages and geochemical studies, document a widespread phase of extension in the southern GEP between latest Oligocene and Early Miocene that subsequently focused in the region of the future Gulf in the Middle Miocene. Upper Oligocene to Lower Miocene rocks across the southern Sierra Madre Occidental (SMO)(northern Nayarit and southern Sinaloa) were affected by major ~N S to NNW striking normal faults prior to ~21 Ma. Then, between ~21 and 11 Ma, a system of NNW-SSE high angle extensional faults continued extending the southwestern side of the SMO. Rhyolitic domes, shallow intrusive bodies, and lesser basalts were emplaced along this extensional belt at 20-17 Ma. In northern Sinaloa, large grabens were floored by huge dome complexes at ~21-17 Ma and filled by continental sediments with interlayered basalts dated at 15-14 Ma, a setting and timing very similar to Sonora. Early to Middle Miocene volcanism, including the largely volcaniclastic Comondú strata in Baja California Sur, was thus emplaced in rift basins and was likely associated to decompression melting of upper mantle (inducing crustal partial melting) rather than to fluxing by fluids from the young subducting plate. Along the Nayarit and Sinaloa coast, flatlying basaltic lava flows dated at 11-10 Ma are exposed just above the present sea level. Here, crustal thickness is almost half that in the unextended core of the SMO, implying significant lithosphere stretching before ~11 Ma. Our study shows that rifting began much earlier than Late Miocene and provided a fundamental control on the style and composition of volcanism from at least 30 Ma. We envision a sustained period of lithospheric stretching and magmatism during which the pace and breadth of extension changed at ~20-18 Ma to be narrower and likely more rapid, and again at ~12.5 Ma, when the kinematics of rifting became more oblique.

Pulling apart the mid to late Cenozoic magmatic record of the Gulf of California : is there a Comondú arc?

The composition of the lithosphere can be fundamentally altered by long-lived subduction processes such that subduction-modified lithosphere can survive for 100's Myrs. Incorrect petrotectonic interpretations result when spatial-temporal-compositional trends of, and source contributions to, magmatism are not properly considered. Western Mexico has had protracted Cenozoic magmatism developed mostly in-board of active oceanic plate subduction beneath western North America. A broad range of igneous compositions from basalt to high-silica rhyolite were erupted with intermediate to silicic compositions in particular, showing calc-alkaline and other typical subduction-related geochemical signatures. A major Oligocene rhyolitic ignimbrite “flare-up” (>300,000 km3) switched to a bimodal volcanic phase in the Early Miocene (~100,000 km3), associated with distributed extension and opening of numerous grabens. Extension became more focussed ~18 Ma resulting in localised volcanic activity along the future site of the Gulf of California. This localised volcanism (known as the Comondú “arc”) was dominantly effusive and andesite-dacite in composition. Past tectonic interpretations of Comondú-age volcanism may have been incorrect as these regional temporal-compositional changes are alternatively interpreted as a result of increased mixing of mantle-derived basaltic and crust-derived rhyolitic magmas in an active rift environment rather than fluid flux melting of the mantle wedge above the subducting Guadalupe Plate.

Late Oligocene to Middle Miocene rifting and synextensional magmatism in the southwestern Sierra Madre Occidental, Mexico : the beginning of the Gulf of California rift

Although Basin and Range–style extension affected large areas of western Mexico after the Late Eocene, most consider that extension in the Gulf of California region began as subduction waned and ended ca. 14–12.5 Ma. A general consensus also exists in considering Early and Middle Miocene volcanism of the Sierra Madre Occidental and Comondú Group as subduction related, whereas volcanism after ca. 12.5 Ma is extension related. Here we present a new regional geologic study of the eastern Gulf of California margin in the states of Nayarit and Sinaloa, Mexico, backed by 43 new Ar-Ar and U-Pb mineral ages, and geochemical data that document an earlier widespread phase of extension. This extension across the southern and central Gulf Extensional Province began between Late Oligocene and Early Miocene time, but was focused in the region of the future Gulf of California in the Middle Miocene. Late Oligocene to Early Miocene rocks across northern Nayarit and southern Sinaloa were affected by major approximately north-south– to north-northwest– striking normal faults prior to ca. 21 Ma. Between ca. 21 and 11 Ma, a system of north-northwest–south-southeast high angle extensional faults continued extending the southwestern side of the Sierra Madre Occidental. Rhyolitic domes, shallow intrusive bodies, and lesser basalts were emplaced along this extensional belt at 20–17 Ma. Rhyolitic rocks, in particular the domes and lavas, often show strong antecrystic inheritance but only a few Mesozoic or older xenocrysts, suggesting silicic magma generation in the mid-upper crust triggered by an extension induced basaltic infl ux. In northern Sinaloa, large grabens were occupied by huge volcanic dome complexes ca. 21–17 Ma and filled by continental sediments with interlayered basalts dated as 15–14 Ma, a stratigraphy and timing very similar to those found in central Sonora (northeastern Gulf of California margin). Early to Middle Miocene volcanism occurred thus in rift basins, and was likely associated with decompression melting of upper mantle (inducing crustal partial melting) rather than with fluxing by fluids from the young and slow subducting microplates. Along the eastern side of the Gulf of California coast, from Farallón de San Ignacio island offshore Los Mochis, Sinaloa, to San Blas, Nayarit, a strike distance of >700 km, flat lying basaltic lavas dated as ca. 11.5–10 Ma are exposed just above the present sea level. Here crustal thickness is almost half that in the unextended core of the adjacent Sierra Madre Occidental, implying signifi cant lithosphere stretching before ca. 11 Ma. This mafic pulse, with subdued Nb-Ta negative spikes, may be related to the detachment of the lower part of the subducted slab, allowing an upward asthenospheric flow into an upper mantle previously modified by fluid fluxes related to past subduction. Widespread eruption of very uniform oceanic island basalt–like lavas occurred by the late Pliocene and Pleistocene, only 20 m.y. after the onset of rifting and ~9 m.y. after the end of subduction, implying that preexisting subduction-modified mantle had now become isolated from melt source regions. Our study shows that rifting across the southern-central Gulf Extensional Province began much earlier than the Late Miocene and provided a fundamental control on the style and composition of volcanism from at least 30 Ma. We envision a sustained period of lithospheric stretching and magmatism during which the pace and breadth of extension changed ca. 20–18 Ma to be narrower, and again after ca. 12.5 Ma, when the kinematics of rifting became more oblique.

Understanding the impact of legislative changes on child car seating and restraint practices in regional Queensland

Road crashes contribute to a significant amount of child mortality and morbidity in Australia. In fact, passenger injuries contribute to the majority of child crash road trauma. A number of factors contribute to child injury and death in motor vehicles, including inappropriate seating position, inappropriate choice of restraint, and incorrect installation and use of child restraints. Prior to March 2010, child restraint legislation in Queensland only required children twelve months and younger to be seated in a properly adjusted and fastened child restraint. This legislation left older infants and young children potentially suboptimally protected. From March 2010, new legislation specified seating position and type of child restraint required, depending on the age of the child. This research was underpinned by the Health Belief Model (HBM), which explores health related behaviour, behaviour change, environmental factors influencing behaviour change (including legislative changes) and is flexible enough to be used in relation to parents' health practices for their children, rather than parent health directly. This thesis investigates the extent to which the changes to child restraint legislation have led parents in regional areas of Queensland to use appropriate restraint practices for their children and determines the extent to which the constructs of the HBM, parental perceptions, barriers and environmental factors contribute to the appropriateness of child seating and restraint use. Study One included three sets of observations taken in two regional cities of Queensland prior to the legislative amendment, during an educative period of six months, and after the enactment of the legislation. Each child's seating position and restraint type were recorded. Results showed that the proportion of children observed occupying the front seat decreased by 15.6 per cent with the announcement the legislation. There was no decrease in front seat use at the enactment of the legislation. The proportion of children observed using dedicated child restraints increased by 8.8 per cent with the announcement of the legislation when there was one child in the vehicle. Further, there was a 10.1 per cent increase in the proportion of children observed using a seat belt that fit with the announcement when there was one child in the vehicle and with the enactment of the legislation regardless of the number of children in the vehicle (21.8 per cent for one child, 39.7 per cent for two children and 40.2 per cent for three or more children). Study Two comprised initial intercept interviews, later followed up by telephone, with parents with children aged eight years and younger at the announcement and telephone interviews at the enactment of the legislation in one regional city in Queensland. Parents reported their child restraint practices, and opinions, knowledge and understanding of the requirements of the new legislation. Parent responses were analysed in terms of the constructs in the HBM. When asked which seating position their child 'usually' used, parents reported child front seat use was nil (0.0 per cent) and did not change with the enactment of the legislative amendment. However, when parents were asked whether they allowed children to use the front seat at some point within the six months prior to the interview, reported child front seat use was 7 (5.4 per cent) children at T2 and 10 (9.6 per cent) at T3. Reported use of age-appropriate child restraints did not increase with the enactment of the legislation (p = 0.77, ns). Parents reported restraint practices were classed as either appropriate or inappropriate. Parents who reported appropriate restraint practices were those whose children were sitting in optimal restraints and seating positions for their age according to the requirements of the legislation. Parents who reported inappropriate restraint practices were those who had one or more children who were suboptimally restrained or seated for their age according to the requirements of the legislation. Neither parents' perceptions about their susceptibility of being in a crash nor the likelihood of severity of child injury if involved in a crash yielded significant differences in the appropriateness of reported parent restraint practices over time with the enactment of the legislation. A trend in the data suggested parents perceived a benefit to using appropriate restraint practices was to avoid fines and demerit points. Over 75 per cent of parents who agreed that child restraints provide better protection for children than an adult seat belt reported appropriately seating and restraining their children (2 (1) = 8.093, p<.05). The self-efficacy measure regarding parents' confidence in installing a child restraint showed a significant association with appropriate parental restraint practices (2 (1) = 7.036, p<.05). Results suggested that some parents may have misinterpreted the announcement of the legislative amendment as the announcement of the enforcement of the legislation instead. Some parents who correctly reported details of the legislation did not report appropriate child restraint practices. This finding shows that parents' knowledge of the legislative amendment does not necessarily have an impact on their behaviour to appropriately seat and restrain children. The results of these studies have important implications for road safety and the prevention of road-related injury and death to children in Queensland. Firstly, parents reported feeling unsure of how to install restraints, which suggests that there may be children travelling in restraints that have not been installed correctly, putting them at risk. Interventions to alert and encourage parents to seek advice when unsure about the correct installation of child restraints could be considered. Secondly, some parents in this study although they were using the most appropriate restraint for their children, reported using a type that was not the most appropriate restraint for the child's age according to the legislation. This suggests that intervention may be effective in helping parents make a more accurate choice of the most appropriate type of restraint to use with children, especially as the child ages and child restraint requirements change. Further research could be conducted to ascertain the most effective methods of informing and motivating parents to use the most appropriate restraints and seating positions for their children, as these results show a concerning disparity between reported restraint practices and those that were observed.

Show me the magic : the adventures of Don McAlpine

Synopsis Show Me The Magic takes us on an enthralling and joyful journey into the life and work of the legendary and world-renowned Australian cinematographer, Don McAlpine. A country kid from the small wheat-belt town of Quandialla in isolated south-western New South Wales, Australia, McAlpine was born in 1934 - the year before the first technicolour film was released. There wasn’t even a cinema in Quandialla. Don helped his mother support their family from the age of 14, when his father was stricken by tuberculosis. His part-time job at the Temora chemist as a darkroom photo developer struck a chord in young Don's soul. Soon, a school performance of The Mikado ignited in him the desire to entertain an audience. His fascination with the magical images emerging from his darkroom set him on the winding path that would eventually lead to the glittering lights of Hollywood, where, in 2009, he received the American Society of Cinematographers’ “International Cinematographer of the Year” Award in front of the foremost luminaries of the American film industry. That same year, Don shot his 50th film, X-Men Origins: Wolverine, a big-budget, effects-driven action movie directed by Oscar-winner Gavin Hood and starring Hugh Jackman. Show Me the Magic takes us on set and behind the scenes of that film. In 2011, Don posted another landmark: Mental, a low budget movie directed by PJ Hogan (Muriel’s Wedding, My Best Friend’s Wedding, Peter Pan). Mental was Don’s first digital film and his first Australian film in 25 years. As we travel with Don back into his past, and into the Australian outback landscape that he loves so much, we experience the extremes of movie making: embedded alongside him on the contrasting sets of Wolverine and Mental, we peel back the layers of what Don calls ‘the beautiful deception' of cinema to illuminate the world behind the screen. Joined by celebrated Australian directors Bruce Beresford and Gillian Armstrong, we explore the heritage of the remarkable Australian films that Don photographed, including the iconic Breaker Morant and My Brilliant Career. In Los Angeles, Don reconnects with Paul Mazursky who gave him his big break in Hollywood with Tempest and followed up with Down and Out in Beverly Hills. And two Australians of a later generation - Baz Luhrmann and Catherine Martin - take us behind the scenes on Don’s spectacular creative achievements – Romeo + Juliet and Moulin Rouge! At once the story of a remarkable man and an exploration of filmmaking at the highest level, Show Me The Magic will engage and entrance anyone who has ever been touched by the magic of movies. - See more at: http://www.showmethemagic.com.au/film.htm#synopsis" This film is dedicated to the memory of South African film-maker Peter Henkel, 1924 - 1992.

Optimisation of lateral load-resisting systems in composite high-rise buildings

This research is carried out by using finite element modelling of building prototypes with three different layouts (rectangular, octagonal and L-shaped) for three different heights (98.0 m, 147.0 m and 199.5 m) for the optimization of lateral load-resisting systems in composite high-rise buildings. Variations of lateral bracings (different number and varied placement along model height of belt-truss and outrigger floors) with RCC (reinforced cement concrete) core wall are used in composite high-rise building models. Prototypes of composite buildings are analysed for dynamic wind and seismic loads. The effects on serviceability (deflection and frequency) of models are studied and conclusions are deduced.

Police officer in-vehicle discomfort : appointments carriage method and vehicle seat features

Musculoskeletal pain is commonly reported by police officers. A potential cause of officer discomfort is a mismatch between vehicle seats and the method used for carrying appointments. Twenty-five police officers rated their discomfort while seated in: (1) a standard police vehicle seat, and (2) a vehicle seat custom-designed for police use. Discomfort was recorded in both seats while wearing police appointments on: (1) a traditional appointments belt, and (2) a load-bearing vest / belt combination (LBV). Sitting in the standard vehicle seat and carrying appointments on a traditional appointments belt were both associated with significantly elevated discomfort. Four vehicle seat features were most implicated as contributing to discomfort: back rest bolster prominence; lumbar region support; seat cushion width; and seat cushion bolster depth. Authorising the carriage of appointments using a LBV is a lower cost solution with potential to reduce officer discomfort. Furthermore, the introduction of custom-designed vehicle seats should be considered.

Fatalities of repair, maintenance, minor alteration, and addition works in Hong Kong

This study examines fatalities of repair, maintenance, minor alteration, and addition (RMAA) works which occurred in Hong Kong between January 2000 and October 2011. A total of 119 RMAA fatalities were recorded. Particular emphasis was placed on fall from height accidents as they accounted for the vast majority of RMAA fatal accidents for the period. A cluster analysis was conducted on fall from height fatal cases. The cluster analysis clearly identified three groups of fall from height fatalities: (1) bamboo scaffolders aged between 25 and 34 who fell from external wall/facade in the beginning of weekdays; (2) miscellaneous workers aged between 45 and 54 who fell from other/unknown places in the end of weekdays; and (3) manual labour aged between 35 and 44 who fell at floor level/from floor openings in weekends. Unsafe process and improper procedures were the main unsafe condition leading to fatalities whereas safety belt not properly used was the main unsafe action leading to fatalities. Specific safety interventions were recommended for each of these groups to help avoid these fatalities.