290 resultados para periglacial slope deposits, anthropogenic over impression, dry maar, Eifel


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The synthesis of alternating copolymers of tetraalkylindenofluorene with bithiophene and terthiophene using Suzuki polycondensation route is reported. We report on the optical and electrochemical properties of these copolymers. AFM analysis of the microscopic morphology of thin deposits showed that the copolymer with terthiophene units produced the more ordered films, with well-defined fibrillar structures, resulting from highly-regular dense packing due to strong π-π interchain interactions, in contrast to the amorphous bithiophene copolymer. Upon testing these materials in FETs the terthienyl copolymers displayed the higher charge mobilities among the studied compounds, with values of over 10-4 cm2 V-1 s-1 being obtained.

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With the growing proliferation of statute laws, the skill of statutory interpretation is an increasingly important aspect of legal practice. Despite the importance, statutory interpretation can be a challenging area of law to teach to undergraduate law students, who may find the topic dry and disengaging when taught through traditional methods. Such disengagement may adversely affect knowledge retention, particularly if the material is taught in the first or second year of study and not explicitly reinforced in subsequent years. Concern over the present standard of statutory interpretation skills being exhibited by practitioners, has prompted the Chief Justice of the Supreme Court of Queensland to contact law schools, enquiring how and to what extent statutory interpretation is being taught...

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Age-related macular degeneration (AMD) affects the central vision and subsequently may lead to visual loss in people over 60 years of age. There is no permanent cure for AMD, but early detection and successive treatment may improve the visual acuity. AMD is mainly classified into dry and wet type; however, dry AMD is more common in aging population. AMD is characterized by drusen, yellow pigmentation, and neovascularization. These lesions are examined through visual inspection of retinal fundus images by ophthalmologists. It is laborious, time-consuming, and resource-intensive. Hence, in this study, we have proposed an automated AMD detection system using discrete wavelet transform (DWT) and feature ranking strategies. The first four-order statistical moments (mean, variance, skewness, and kurtosis), energy, entropy, and Gini index-based features are extracted from DWT coefficients. We have used five (t test, Kullback–Lieber Divergence (KLD), Chernoff Bound and Bhattacharyya Distance, receiver operating characteristics curve-based, and Wilcoxon) feature ranking strategies to identify optimal feature set. A set of supervised classifiers namely support vector machine (SVM), decision tree, k -nearest neighbor ( k -NN), Naive Bayes, and probabilistic neural network were used to evaluate the highest performance measure using minimum number of features in classifying normal and dry AMD classes. The proposed framework obtained an average accuracy of 93.70 %, sensitivity of 91.11 %, and specificity of 96.30 % using KLD ranking and SVM classifier. We have also formulated an AMD Risk Index using selected features to classify the normal and dry AMD classes using one number. The proposed system can be used to assist the clinicians and also for mass AMD screening programs.

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Lower airway inflammation is generally classified as eosinophilic or neutrophilic. In conditions where eosinophilic inflammation predominates such as asthma in children, corticosteroids are usually beneficial. Traditionally, lower airway eosinophilia is measured using cellular count (through bronchoalveolar lavage or induced sputum). Both methods have limited applicability in children. When instruments to measure fractional exhaled nitric oxide (FeNO) became available, it presented an attractive option as it provided a non-invasive method of measuring eosinophilic inflammation suitable for children and adult. Not surprisingly, proposals have been made that FeNO measurement can be clinically used in many scenarios including monitoring the response to anti-inflammatory medications, to verify the adherence to treatment, and to predict upcoming asthma exacerbations. This thesis addresses the utility of FeNO levels in various scenarios, specifically in relation to asthma control and cough, a contentious aspect of the diagnosis of asthma. The thesis consists of a series of systematic reviews (related to the main question) and original studies in children. The over-arching aim of the thesis is to determine if FeNO is a clinically useful tool in the management of asthma and common asthma symptoms. The specific aims of the thesis were, to: 1. Determine if children with asthma have more severe acute respiratory symptoms at presentation with an asthma exacerbation and at days 7, 10 and 14 using validated scales. We also examined if children with asthma were more likely to have a persistent cough on day 14 than children with protracted bronchitis and/or controls. 2. Evaluate the efficacy of tailoring asthma interventions based on sputum analysis in comparison to clinical symptoms (with or without spirometry/peak flow) for asthma related outcomes in children and adults. 3. Evaluate the efficacy of tailoring asthma interventions based on exhaled nitric oxide in comparison to clinical symptoms (with or without spirometry/peak flow) for asthma related outcomes in children and adults. 4. Determine if adjustment of asthma medications based on FeNO levels (compared to management based on clinical symptoms) reduces severe exacerbations in children with asthma. 5. Examine the relationship between FeNO and exercise induced broncho-constriction and cough in children The aims above are addressed in respective chapters and all but one has been published/submitted. A synopsis of the findings are: In study-1 (Aim 1), we found that children with protracted bronchitis had the most severe acute respiratory infection symptoms and higher percentage of respiratory morbidity at day 14 in comparison to children with asthma and healthy controls. The systematic review of study-2 (Aim 2) included 246 randomised adult participants (no children) with 221 completing the trials. In the meta-analysis, a significant reduction in number of participants who had one or more asthma exacerbations occurred when treatment was based on sputum eosinophils in comparison to clinical symptoms. In the systematic review of study-3 (Aim 3), we found no significant difference between the intervention group (treatment adjusted based on FeNO) and control group (treatment adjusted based on clinical symptoms) for the primary outcome of asthma exacerbations or for the other outcomes (clinical symptoms, FeNO level and spirometry). In post-hoc analysis, a significant reduction in mean final daily dose ICS per adult was found in the group where treatment was based on FeNO in comparison to clinical symptoms. In contrast, in the paediatric studies, there was a significant increase in ICS dose in the FeNO strategy arm. Thus, controversy remains of the benefit or otherwise of utilising exhaled nitric oxide (FeNO) in routine clinical practice. FeNO levels are dependent on atopy and none of the 7 published trials have considered atopic status in FeNO levels when medications were adjusted. In study-4 (Aim 4), 64 children with asthma were recruited. Their asthma medications were adjusted according to either FeNO levels or usual clinical care utilising a management hierarchy taking into account atopy. It was concluded that tailoring of asthma medications in accordance to FeNO levels (compared to usual management), taking into account atopy status, reduced the number of children with severe exacerbations. However, a FeNO-based strategy resulted in higher daily ICS doses and had no benefit on asthma control. In study-5 (Aim 5), 33 children with cough and 17 controls were recruited. They were randomised to undertake an exercise challenge on day 1, or dry powder mannitol challenge on day 1 (with alternative challenge being done on day 2). In addition, a 24 hour cough meter, skin prick test, capsaicin cough sensitivity test and cough diary were undertaken. The change in cough frequency post exercise was significantly increased in the children with cough. FeNO decreases post exercise regardless of whether EIB is present or not. Limitations in the studies were addressed in the respective chapters. In summary, the studies from this thesis have provided new information on: • The severity of respiratory symptoms was increased in the early phase of the asthma exacerbation but not in the later recovery phase when compared with controls. • The utility of FeNO in the management of children with asthma. • The relationship of FeNO, cough and EIB in children. • Systematic reviews on the efficacy of tailoring asthma interventions based on eosinophilic inflammatory markers (sputum analysis and FeNO) in comparison to clinical symptoms.

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Communicating the mining industry’s water use is fundamental to maintaining its social license to operate but the majority of corporate reporting schemes list indicators. The Minerals Council of Australia’s Water Accounting Framework was designed to assist the minerals industry obtain consistency in its accounting method and in the definitions of terms used in water reporting. The significance of this paper is that it shows that the framework has been designed to be sufficiently robust to describe any mining/mineral related operation. The Water Accounting Framework was applied across four operations over three countries producing four commodities. The advantages of the framework were then evident through the presentation of the reports. The contextual statement of the framework was able to explain contrasting reuse efficiencies. The Input-Output statements showed that evaporation was a significant loss for most of the operations in the study which highlights a weakness of reporting schemes that focus on discharge volumes. The framework method promotes data reconciliation which proved the presence of flows that two operations in the study had neglected to provide. Whilst there are many advantages of the framework, the major points are that the reporting statements of the framework, when presented together, can better enable the public to understand water interactions at a site-level and allows for valid comparisons between sites, regardless of locale and commodity. With mining being a global industry, these advantages are best realised if there was international adoption of the framework.

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A collaborative series of limited edition canvas tote bags, each bearing a different feminist slogan, produced by the feminist collective LEVEL for exhibition and distribution as part of the Queensland Government-funded Q[ARI] Project at Sydney Contemporary Art Fair at Carriageworks in 2013.

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Commercially viable carbon–neutral biodiesel production from microalgae has potential for replacing depleting petroleum diesel. The process of biodiesel production from microalgae involves harvesting, drying and extraction of lipids which are energy- and cost-intensive processes. The development of effective large-scale lipid extraction processes which overcome the complexity of microalgae cell structure is considered one of the most vital requirements for commercial production. Thus the aim of this work was to investigate suitable extraction methods with optimised conditions to progress opportunities for sustainable microalgal biodiesel production. In this study, the green microalgal species consortium, Tarong polyculture was used to investigate lipid extraction with hexane (solvent) under high pressure and variable temperature and biomass moisture conditions using an Accelerated Solvent Extraction (ASE) method. The performance of high pressure solvent extraction was examined over a range of different process and sample conditions (dry biomass to water ratios (DBWRs): 100%, 75%, 50% and 25% and temperatures from 70 to 120 ºC, process time 5–15 min). Maximum total lipid yields were achieved at 50% and 75% sample dryness at temperatures of 90–120 ºC. We show that individual fatty acids (Palmitic acid C16:0; Stearic acid C18:0; Oleic acid C18:1; Linolenic acid C18:3) extraction optima are influenced by temperature and sample dryness, consequently affecting microalgal biodiesel quality parameters. Higher heating values and kinematic viscosity were compliant with biodiesel quality standards under all extraction conditions used. Our results indicate that biodiesel quality can be positively manipulated by selecting process extraction conditions that favour extraction of saturated and mono-unsaturated fatty acids over optimal extraction conditions for polyunsaturated fatty acids, yielding positive effects on cetane number and iodine values. Exceeding biodiesel standards for these two parameters opens blending opportunities with biodiesels that fall outside the minimal cetane and maximal iodine values.

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The mining industry faces three long term strategic risks in relation to its water and energy use: 1) securing enough water and energy to meet increased production; 2) reducing water use, energy consumption and emissions due to social, environmental and economic pressures; and 3) understanding the links between water and energy, so that an improvement in one area does not create an adverse effect in another. This project helps the industry analyse these risks by creating a hierarchical systems model (HSM) that represents the water and energy interactions on a sub-site, site and regional scales; which is coupled with a flexible risk framework. The HSM consists of: components that represent sources of water and energy; activities that use water and energy and off-site destinations of water and produced emissions. It can also represent more complex components on a site, with inbuilt examples including tailings dams and water treatment plants. The HSM also allows multiple sites and other infrastructure to be connected together to explore regional water and energy interactions. By representing water and energy as a single interconnected system the HSM can explore tradeoffs and synergies. For example, on a synthetic case study, which represents a typical site, simulations suggested that while a synergy in terms of water use and energy use could be made when chemical additives were used to enhance dust suppression, there were trade-offs when either thickened tailings or dry processing were used. On a regional scale, the HSM was used to simulate various scenarios, including: mines only withdrawing water when needed; achieving economics-of-scale through use of a single centralised treatment plant rather than smaller decentralised treatment plants; and capturing of fugitive emissions for energy generation. The HSM also includes an integrated risk framework for interpreting model output, so that onsite and off-site impacts of various water and energy management strategies can be compared in a managerial context. The case studies in this report explored company, social and environmental risks for scenarios of regional water scarcity, unregulated saline discharge, and the use of plantation forestry to offset carbon emissions. The HSM was able to represent the non-linear causal relationship at the regional scale, such as the forestry scheme offsetting a small percentage of carbon emissions but causing severe regional water shortages. The HSM software developed in this project will be released as an open source tool to allow industry personnel to easily and inexpensively quantify and explore the links between water use, energy use, and carbon emissions. The tool can be easily adapted to represent specific sites or regions. Case studies conducted in this project highlighted the potential complexity of these links between water, energy, and carbon emissions, as well as the significance of the cumulative effects of these links over time. A deeper understanding of these links is vital for the mining industry in order to progress to more sustainable operations, and the HSM provides an accessible, robust framework for investigating these links.

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As the cost of mineral fertilisers increases globally, organic soil amendments (OAs) from agricultural sources are increasingly being used as substitutes for nitrogen. However, the impact of OAs on the production of greenhouse gases (CO2 and N2O) is not well understood. A 60-day laboratory incubation experiment was conducted to investigate the impacts of applying OAs (equivalent to 296 kg N ha−1 on average) on N2O and CO2 emissions and soil properties of clay and sandy loam soils from sugar cane production. The experiment included 6 treatments, one being an un-amended (UN) control with addition of five OAs being raw mill mud (MM), composted mill mud (CM), high N compost (HC), rice husk biochar (RB), and raw mill mud plus rice husk biochar (MB). These OAs were incubated at 60, 75 and 90% water-filled pore space (WFPS) at 25°C with urea (equivalent to 200 kg N ha−1) added to the soils thirty days after the incubation commenced. Results showed WFPS did not influence CO2 emissions over the 60 days but the magnitude of emissions as a proportion of C applied was RB < CM < MB < HC dry matter and C/N ratio of the OAs, WFPS, and the soil CEC. Application of RB reduced N2O emissions by as much as 42-64% depending on WFPS. The reductions in both CO2 and N2O emissions after application of RB were due to a reduced bioavailability of C and not immobilisation of N. These findings show that the effect of OAs on soil GHG emissions can vary substantially depending on their chemical properties. OAs with a high availability of labile C and N can lead to elevated emissions of CO2 and N2O, while rice husk biochar showed potential in reducing overall soil GHG emissions.

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Introduction and Aims. The rate of alcohol-related emergency department (ED) presentations in young people has increased dramatically in recent decades. Injuries are the most common type of youth alcohol-related ED presentation, yet little is known about these injuries in young people. This paper describes the characteristics of alcohol-related ED injury presentations in young people over a 13-year period and determines if they differ by gender and/or age group (adolescents: 12–17 years; young adults: 18–24 years). Design and Method. The Queensland Injury Surveillance Unit (QISU) database collects injury surveillance data at triage in participating EDs throughout Queensland, Australia. A total of 4667 cases of alcohol-related injuries in young people (aged 12–24 years) were identified in the QISU database between January 1999 and December 2011, using an injury surveillance code and nursing triage text-based search strategy. Results. Overall, young people accounted for 38% of all QISU alcohol-related ED injury presentations in patients aged 12 years or over. The majority of young adults presented with injuries due to violence and falls, whereas adolescents presented due to self-harm or intoxication without other injury. Males presented with injuries due to violence, whereas females presented with alcohol-related self-harm and intoxication. Discussion and Conclusions. There is a need for more effective ways of identifying the degree of alcohol involvement in injuries among young people presenting to EDs.

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Objectives: The purpose of this study was to investigate the characteristics associated with fatal and non-fatal low-speed vehicle run-over (LSVRO) events in relation to person, incident and injury characteristics, in order to identify appropriate points for intervention and injury prevention. Methods: Data on all known LSVRO events in Queensland, Australia, over 11 calendar years (1999–2009) were extracted from five different databases representing the continuum of care ( prehospital to fatality) and manually linked. Descriptive and multivariate analyses were used to analyse the sample characteristics in relation to demographics, health service usage, outcomes, incident characteristics, and injury characteristics. Results: Of the 1641 LSVRO incidents, 98.4% (n=1615) were non-fatal, and 1.6% were fatal (n=26). Over half the children required admission to hospital (56%, n=921); mean length of stay was 3.4 days. Younger children aged 0–4 years were more frequently injured, and experienced more serious injuries with worse outcomes. Patterns of injury (injury type and severity), injury characteristics (eg, time of injury, vehicle type, driver of vehicle, incident location), and demographic characteristics (such as socioeconomic status, indigenous status, remoteness), varied according to age group. Almost half (45.6%; n=737) the events occurred outside major cities, and approximately 10% of events involved indigenous children. Parents were most commonly the vehicle drivers in fatal incidents. While larger vehicles such as four-wheel drives (4WD) were most frequently involved in LSVRO events resulting in fatalities, cars were most frequently involved in non-fatal events. Conclusions: This is the first study, to the authors’ knowledge, to analyse the characteristics of fatal and non-fatal LSVRO events in children aged 0–15 years on a state-wide basis. Characteristics of LSVRO events varied with age, thus age-specific interventions are required. Children living outside major cities, and indigenous children, were over-represented in these data. Further research is required to identify the burden of injury in these groups.

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Background The purpose of this study was to estimate the incidence of fatal and non-fatal Low Speed Vehicle Run Over (LSVRO) events among children aged 0–15 years in Queensland, Australia, at a population level. Methods Fatal and non-fatal LSVRO events that occurred in children resident in Queensland over eleven calendar years (1999-2009) were identified using ICD codes, text description, word searches and medical notes clarification, obtained from five health related data bases across the continuum of care (pre-hospital to fatality). Data were manually linked. Population data provided by the Australian Bureau of Statistics were used to calculate crude incidence rates for fatal and non-fatal LSVRO events. Results There were 1611 LSVROs between 1999–2009 (IR = 16.87/100,000/annum). Incidence of non-fatal events (IR = 16.60/100,000/annum) was 61.5 times higher than fatal events (IR = 0.27/100,000/annum). LSVRO events were more common in boys (IR = 20.97/100,000/annum) than girls (IR = 12.55/100,000/annum), and among younger children aged 0–4 years (IR = 21.45/100000/annum; 39% or all events) than older children (5–9 years: IR = 16.47/100,000/annum; 10–15 years IR = 13.59/100,000/annum). A total of 896 (56.8%) children were admitted to hospital for 24 hours of more following an LSVRO event (IR = 9.38/100,000/annum). Total LSVROs increased from 1999 (IR = 14.79/100,000) to 2009 (IR = 18.56/100,000), but not significantly. Over the 11 year period, there was a slight (non –significant) increase in fatalities (IR = 0.37-0.42/100,000/annum); a significant decrease in admissions (IR = 12.39–5.36/100,000/annum), and significant increase in non-admissions (IR = 2.02-12.77/100,000/annum). Trends over time differed by age, gender and severity. Conclusion This is the most comprehensive, population-based epidemiological study on fatal and non-fatal LSVRO events to date. Results from this study indicate that LSVROs incur a substantial burden. Further research is required on the characteristics and risk factors associated with these events, in order to adequately inform injury prevention. Strategies are urgently required in order to prevent these events, especially among young children aged 0-4 years.

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This paper describes the electrocatalytic oxidation of ascorbic acid (AA) in phosphate buffer solution by the immobilized citrate capped gold nanoparticles (AuNPs) on 1,6-hexanedithiol (HDT) modified Au electrode. X-ray photoelectron spectrum (XPS) of HDT suggests that it forms a monolayer on Au surface through one of the two single bondSH groups and the other single bondSH group is pointing away from the electrode surface. The free single bondSH groups of HDT were used to covalently attach colloidal AuNPs. The covalent attachment of AuNPs on HDT monolayer was confirmed from the observed characteristic carboxylate ion stretching modes of citrate attached with AuNPs in the infra-red reflection absorption spectrum (IRRAS) in addition to a higher reductive desorption charges obtained for AuNPs immobilized on HDT modified Au (Au/HDT/AuNPs) electrode in 0.1 M KOH when compared to HDT modified Au (Au/HDT) electrode. The electron transfer reaction of [Fe(CN)6]4−/3− was markedly hindered at the HDT modified Au (Au/HDT) electrode while it was restored with a peak separation of 74 mV after the immobilization of AuNPs on Au/HDT (Au/HDT/AuNPs) electrode indicating a good electronic communication between the immobilized AuNPs and the underlying bulk Au electrode through a HDT monolayer. The Cottrell slope obtained from the potential-step chronoamperometric measurements for the reduction of ferricyanide at Au/HDT/AuNPs was higher than that of bare Au electrode indicating the increased effective surface area of AuNPs modified electrode. The Au/HDT/AuNPs electrode exhibits excellent electrocatalytic activity towards the oxidation of ascorbic acid (AA) by enhancing the oxidation peak current to more than two times with a 210 mV negative shift in the oxidation potential when compared to a bare Au electrode. The standard heterogeneous electron transfer rate constant (ks) calculated for AA oxidation at Au/HDT/AuNPs electrode was 5.4 × 10−3 cm s−1. The oxidation peak of AA at Au/HDT/AuNPs electrode was highly stable upon repeated potential cycling. Linear calibration plot was obtained for AA over the concentration range of 1–110 μM with a correlation coefficient of 0.9950. The detection limit of AA was found to be 1 μM. The common physiological interferents such as glucose, oxalate ions and urea do not show any interference within the detection limit of AA. The selectivity of the AuNPs modified electrode was illustrated by the determination of AA in the presence of uric acid.

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Governments around the world want to know a lot about who we are and what we’re doing online and they want communications companies to help them find it. We don’t know a lot about when companies hand over this data, but we do know that it’s becoming increasingly common.