939 resultados para Local anesthetics, Lipid membrane


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In order to provide realistic data for air pollution inventories and source apportionment at airports, the morphology and composition of ultrafine particles (UFP) in aircraft engine exhaust were measured and characterized. For this purpose, two independent measurement techniques were employed to collect emissions during normal takeoff and landing operations at Brisbane Airport, Australia. PM1 emissions in the airfield were collected on filters and analyzed using the particle-induced X-ray emission (PIXE) technique. Morphological and compositional analyses of individual ultrafine particles in aircraft plumes were performed on silicon nitride membrane grids using transmission electron microscopy (TEM) combined with energy-dispersive X-ray microanalysis (EDX). TEM results showed that the deposited particles were in the range of 5 to 100 nm in diameter, had semisolid spherical shapes and were dominant in the nucleation mode (18 – 20 nm). The EDX analysis showed the main elements in the nucleation particles were C, O, S and Cl. The PIXE analysis of the airfield samples was generally in agreement with the EDX in detecting S, Cl, K, Fe and Si in the particles. The results of this study provide important scientific information on the toxicity of aircraft exhaust and their impact on local air quality.

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We propose a new route to hydrogen isotope separation which exploits the quantum sieving effect in the context of transmission through asymmetrically decorated, doped porous graphenes. Selectivities of D2 over H2 as well as rate constants are calculated based on ab initio interaction potentials for passage through pure and nitrogen functionalized porous graphene. One-sided dressing of the membrane with metal provides the critical asymmetry needed for an energetically favorable pathway.

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A solar thermal membrane distillation pilot plant was operated for over 70 days in field conditions. The pilot plant incorporated a single spiral wound permeate gap membrane distillation style of module. All energy used to operate the unit was supplied by solar hot water collectors and photovoltaic panels. The process was able to produce a distillate stream of product water with a conductivity less than 10 µS/cm. Feed water concentration varied from 2,400 µS/cm to 106,000 µS/cm. The process is expected to find application in the production of drinking water for remote island and arid regions without the consumption of electrical energy.

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In a recent paper, Gordon, Muratov, and Shvartsman studied a partial differential equation (PDE) model describing radially symmetric diffusion and degradation in two and three dimensions. They paid particular attention to the local accumulation time (LAT), also known in the literature as the mean action time, which is a spatially dependent timescale that can be used to provide an estimate of the time required for the transient solution to effectively reach steady state. They presented exact results for three-dimensional applications and gave approximate results for the two-dimensional analogue. Here we make two generalizations of Gordon, Muratov, and Shvartsman’s work: (i) we present an exact expression for the LAT in any dimension and (ii) we present an exact expression for the variance of the distribution. The variance provides useful information regarding the spread about the mean that is not captured by the LAT. We conclude by describing further extensions of the model that were not considered by Gordon,Muratov, and Shvartsman. We have found that exact expressions for the LAT can also be derived for these important extensions...

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Fire safety design of building structures has received greater attention in recent times due to continuing losses of properties and lives in fires. However, the structural behaviour of thin-walled cold-formed steel columns under fire conditions is not well understood despite the increasing use of light gauge steels in building construction. Cold-formed steel columns are often subject to local buckling effects. Therefore a series of laboratory tests of lipped and unlipped channel columns made of varying steel thicknesses and grades was undertaken at uniform elevated temperatures up to 700°C under steady state conditions. Finite element models of the tested columns were also developed, and their elastic buckling and nonlinear analysis results were compared with test results at elevated temperatures. Effects of the degradation of mechanical properties of steel with temperature were included in the finite element analyses. The use of accurately measured yield stress, elasticity modulus and stress-strain curves at elevated temperatures provided a good comparison of the ultimate loads and load-deflection curves from tests and finite element analyses. The commonly used effective width design rules and the direct strength method at ambient temperature were then used to predict the ultimate loads at elevated temperatures by using the reduced mechanical properties. By comparing these predicted ultimate loads with those from tests and finite element analyses, the accuracy of using this design approach was evaluated.

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The decentralisation reform in Indonesia has mandated the Central Government to transfer some functions and responsibilities to local governments including the transfer of human resources, assets and budgets. Local governments became giant asset holders almost overnight and most were ill prepared to handle these transformations. Assets were transferred without analysing local government need, ability or capability to manage the assets and no local government was provided with an asset management framework. Therefore, the aim of this research is to develop a Public Asset Management Framework for provincial governments in Indonesia, especially for infrastructure and real property assets. This framework will enable provincial governments to develop integrated asset management procedures throughout asset‘s lifecycle. Achieving the research aim means answering the following three research questions; 1) How do provincial governments in Indonesia currently manage their public assets? 2) What factors influence the provincial governments in managing these public assets? 3) How is a Public Asset Management Framework developed that is specific for the Indonesian provincial governments‘ situation? This research applied case studies approach after a literature review; document retrieval, interviews and observations were collated. Data was collected in June 2009 (preliminary data collection) and January to July 2010 in the major eastern Indonesian provinces. Once the public asset management framework was developed, a focus group was used to verify the framework. Results are threefold and indicate that Indonesian provincial governments need to improve the effectiveness and efficiency of current practice of public asset management in order to improve public service quality. The second result shows that the 5 major concerns that influence the local government public asset management processes are asset identification and inventory systems, public asset holding, asset guidance and legal arrangements, asset management efficiency and effectiveness, and, human resources and their organisational arrangements. The framework was then applied to assets already transferred to local governments and so included a system of asset identification and a needs analysis to classify the importance of these assets to local governments, their functions and responsibilities in delivering public services. Assets that support local government functions and responsibilities will then be managed using suitable asset lifecycle processes. Those categorised as surplus assets should be disposed. Additionally functions and responsibilities that do not need an asset solution should be performed directly by local governments. These processes must be measured using performance measurement indicators. All these stages should be guided and regulated with sufficient laws and regulations. Constant improvements to the quality and quantity of human resources hold an important role in successful public asset management processes. This research focuses on developing countries, and contributes toward the knowledge of a Public Asset Management Framework at local government level, particularly Indonesia. The framework provides local governments a foundation to improve their effectiveness and efficiency in managing public assets, which could lead to improved public service quality. This framework will ensure that the best decisions are made throughout asset decision ownership and provide a better asset life cycle process, leading to selection of the most appropriate asset, improve its acquisition and delivery process, optimise asset performance, and provide an appropriate disposal program.

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Current literature warns organisations about a global ageing phenomenon. Workplace ageing is causing a diminishing work pool which has consequences for a sustainable workforce in the future. This phenomenon continues to impact on local government councils in Australia. Australia has one of the world’s most rapidly ageing populations, and there is evidence that Australian local government councils are already resulting in an unsustainable workforce. Consequently, this research program investigated the role of older workers in the Queensland local government workplace in enabling them to extend their working lives towards transitional employment and a sustainable workforce in the future. Transitional Employment is intended as a strategy for enabling individuals to have greater control over their employment options and their employability during the period leading to their final exit from the workforce. There was no evidence of corporate support for older workers in Queensland local government councils other than tokenistic government campaigns encouraging organisations to "better value their older workers". (Queensland Government, 2007d, p.6). TE is investigated as a possible intervention for older workers in the future. The international and national literature review reflected a range of matters impacting on current older workers in the workforce and barriers preventing them from accessing services towards extending their employment beyond the traditional retirement age (60 years) as defined by the Australian Government; an age when individuals can access their superannuation. Learning and development services were identified as one of those barriers. There was little evidence of investment in or consistent approaches to supporting older workers by organisations. Learning and development services appeared at best to be ad hoc, reactive to corporate productivity and outputs with little recognition of the ageing phenomenon (OECD, 2006, p.23) and looming skills and labour shortages (ALGA, 2006, p. 19). Themes from the literature review led to the establishment of three key research questions: 1. What are the current local government workforce issues impacting on skills and labour retention? 2. What are perceptions about the current workplace environment? And, 3. What are the expectations about learning and development towards extending employability of older workers within the local government sector? The research questions were explored by utilising three qualitative empirical studies, using some numerical data for reporting and comparative analysis. Empirical Study One investigated common themes for accessing transitional employment and comprised two phases. A literature review and Study One data analysis enabled the construction of an initial Transitional Employment Model which includes most frequent themes. Empirical Study Two comprised focus groups to further consider those themes. This led to identification of issues impacting the most on access to learning and development by older workers and towards a revised TEM. Findings presented majority support for transitional employment as a strategy for supporting older workers to work beyond their traditional retirement age. Those findings are presented as significant issues impacting on access to transitional employment within the final 3-dimensionsal TEM. The model is intended as a guide for responding to an ageing workforce by local government councils in the future. This study argued for increased and improved corporate support, particularly for learning and development services for older workers. Such support will enable older workers to maintain their employability and extend their working lives; a sustainable workforce in the future.

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Ramp metering is an effective motorway control tool beneficial for mainline traffic, but the long on-ramp queues created interfere with surface traffic profoundly. This study deals with the conflict between mainline benefits and thecosts of on-ramp and surface traffic. A novel local on-ramp queue management strategy with mainline speed recovery is proposed. Microscopic simulation is used to test the new strategy and compare it with other strategies. Simulation results reveal that the ramp metering with queue management strategy provides a good balance between the mainline and on-ramp performances.

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In this letter the core-core-valence Auger transitions of an atomic impurity, both in bulk or adsorbed on a jellium-like surface, are computed within a DFT framework. The Auger rates calculated by the Fermi golden rule are compared with those determined by an approximate and simpler expression. This is based on the local density of states (LDOS) with a core hole present, in a region around the impurity nucleus. Different atoms, Na and Mg, solids, Al and Ag, and several impurity locations are considered. We obtain an excellent agreement between KL1V and KL23V rates worked out with the two approaches. The radius of the sphere in which we calculate the LDOS is the relevant parameter of the simpler approach. Its value only depends on the atomic species regardless of the location of the impurity and the type of substrate. (C) 2003 Elsevier B.V. All rights reserved.

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In order to meet the land use and infrastructure needs of the community with the additional challenges posed by climate change and a global recession, it is essential that Queensland local governments test their proposed integrated land use and infrastructure plans to ensure the maximum achievement of triple-bottom line sus-tainability goals. Extensive regulatory impact assessment systems are in place at the Australian and state government levels to substantiate and test policy and legislative proposals, however no such requirement has been extended to the local government level. This paper contends that with the devolution of responsibility to local government and growing impacts of local government planning and development assessment activities, impact assessment of regulatory planning instruments is appropriate and overdue. This is particularly so in the Queensland context where local governments manage metropolitan and regional scale responsibilities and their planning schemes under the Sustainable Planning Act 2009 integrate land use and infrastructure planning to direct development rights, the spatial allocation of land, and infrastructure investment. It is critical that urban planners have access to fit-for-purpose impact assessment frameworks which support this challenging task and address the important relationship between local planning and sustainable urban development. This paper uses two examples of sustainability impact assessment and a case study from the Queensland local urban planning context to build an argument and potential starting point for impact assessment in local planning processes.

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Application of "advanced analysis" methods suitable for non-linear analysis and design of steel frame structures permits direct and accurate determination of ultimate system strengths, without resort to simplified elastic methods of analysis and semi-empirical specification equations. However, the application of advanced analysis methods has previously been restricted to steel frames comprising only compact sections that are not influenced by the effects of local buckling. A research project has been conducted with the aim of developing concentrated plasticity methods suitable for practical advanced analysis of steel frame structures comprising non-compact sections. This paper contains a comprehensive set of analytical benchmark solutions for steel frames comprising non-compact sections, which can be used to verify the accuracy of simplified concentrated plasticity methods of advanced analysis. The analytical benchmark solutions were obtained using a distributed plasticity shell finite element model that explicitly accounts for the effects of gradual cross-sectional yielding, longitudinal spread of plasticity, initial geometric imperfections, residual stresses, and local buckling. A brief description and verification of the shell finite element model is provided in this paper.

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Purpose: One of the challenges associated with cell-based therapies for repairing the retina is the development of suitable materials on which to grow and transplant retinal cells. Using the ARPE-19 cell line, we have previously demonstrated the feasibility of growing RPE-derived cells on membranes prepared from the silk protein fibroin. The present study was aimed at developing a porous, ultra-thin fibroin membrane that might better support development of apical-basal polarity in culture, and to extend this work to primary cultures of human RPE cells. Methods: Ultra-thin fibroin membranes were prepared using a highly polished casting table coated with Topas® (a cyclic olefin copolymer) and a 1:0.03 aqueous solution of fibroin and PEO (Mv 900 000 g/mol). Following drying, the membranes were water annealed to make them water-stable, washed in water to remove PEO, sterilised by treatment with 95% ethanol, and washed extensively in saline. Primary cultures containing human RPE cells were established from donor posterior eye cups and maintained in DMEM/F12 medium supplemented with 10% fetal bovine serum and antibiotics. First passage cultures were seeded onto fibroin membranes pre-coated with vitronectin and grown for 6 weeks in medium supplemented with 1% serum. Comparative cultures were established on porous 1.0 µm pore PET membrane (Millipore) and using ARPE-19 cells. Results: The fibroin membranes displayed an average thickness of 3 µm and contained numerous dimples/pore-like structures of up to 3-5 µm in diameter. The primary cultures predominantly contained pigmented epithelial cells, but mesenchymal cells (presumed fibroblasts) were also often present. Passaged cultures appeared to attach equally well to either fibroin or PET membranes. Over time cells on either material adopted a more cobblestoned morphology. Conclusions: Progress has been made towards developing a porous ultra-thin fibroin membrane that supports cultivation of RPE cells. Further studies are required to determine the degree of membrane permeability and RPE polarity.

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Two recent decisions of the Supreme Court of New South Wales in the context of obstetric management have highlighted firstly, the importance of keeping legible, accurate and detailed medical records; and secondly, the challenges faced by those seeking to establish causation, particularly where epidemiological evidence is relied upon...

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In this paper, we explore the effectiveness of patch-based gradient feature extraction methods when applied to appearance-based gait recognition. Extending existing popular feature extraction methods such as HOG and LDP, we propose a novel technique which we term the Histogram of Weighted Local Directions (HWLD). These 3 methods are applied to gait recognition using the GEI feature, with classification performed using SRC. Evaluations on the CASIA and OULP datasets show significant improvements using these patch-based methods over existing implementations, with the proposed method achieving the highest recognition rate for the respective datasets. In addition, the HWLD can easily be extended to 3D, which we demonstrate using the GEV feature on the DGD dataset, observing improvements in performance.

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This study investigates the role of development planning in empowering rural communities in Indonesia’s decentralised era. Evidence is produced that the combination of procedural justice in planning development and social learning in its implementation can assist self-organisation and help empower local communities. Significant benefits are shown to result in: the acquisition and use of collective resources; the development of shared knowledge, skills, values and trust; community leadership; and the development of social networks. Two features of this empowerment model are community-based planning, utilising participatory rural appraisal at the level of the natural village, and the organisation of collective action. These are shown to be effective ways of incorporating procedural justice and social learning in self organisation and community empowerment.