993 resultados para authentic material
Resumo:
Literacy Theories for the Digital Age insightfully brings together six essential approaches to literacy research and educational practice. The book provides powerful and accessible theories for readers, including Socio-cultural, Critical, Multimodal, Socio-spatial, Socio-material and Sensory Literacies. The brand new Sensory Literacies approach is an original and visionary contribution to the field, coupled with a provocative foreword from leading sensory anthropologist David Howes. This dynamic collection explores a legacy of literacy research while showing the relationships between each paradigm, highlighting their complementarity and distinctions. This highly relevant compendium will inspire readers to explore new frontiers of thought and practice in times of diversity and technological change.
Resumo:
Injured bone initiates the healing process by forming a blood clot at the damaged site. However, in severe damage, synthetic bone implants are used to provide structural integrity and restore the healing process. The implant unavoidably comes into direct contact with whole blood, leading to a blood clot formation on its surface. Despite this, most research in bone tissue engineering virtually ignores the important role of a blood clot in supporting healing. Surface chemistry of a biomaterial is a crucial property in mediating blood-biomaterials interactions, and hence the formation of the resultant blood clot. Surfaces presenting mixtures of functional groups carboxyl (–COOH) and methyl (–CH3) have been shown to enhance platelet response and coagulation activation, leading to the formation of fibrin fibres. In addition, it has been shown that varying the compositions of these functional groups and the length of alkyl groups further modulate the immune complement response. In this study, we hypothesised that a biomaterial surface with mixture of –COOH/–CH3(methyl), –CH2CH3 (ethyl) or –(CH2)3CH3 (butyl) groups at different ratios would modulate blood coagulation and complement activation, and eventually tailor the structural and functional properties of the blood clot formed on the surface, which subsequently impacts new bone formation. Firstly, we synthesised a series of materials composed of acrylic acid (AA), and methyl (MMA), ethyl (EMA) or butyl methacrylates (BMA) at different ratios and coated on the inner surfaces of incubation vials. Our surface analysis showed that the amount of –COOH groups on the surface coatings was lower than the ratios of AA prepared in the materials even though the surface content of –COOH groups increased with increasing in AA ratios. It was indicated that the surface hydrophobicity increased with increasing alkyl chain length: –CH 3 > –CH2CH3 > –(CH2)3CH3, and decreased with increasing –COOH groups. No significant differences in surface hydrophobicity was found on surfaces with –CH3 and –CH2CH3 groups in the presence of –COOH groups. The material coating was as smooth as uncoated glass and without any major flaws. The average roughness of material-coated surface (3.99 ± 0.54 nm) was slightly higher than that of uncoated glass surface (2.22 ± 0.29 nm). However, no significant differences in surface average roughness was found among surfaces with the same functionalities at different –COOH ratios nor among surfaces with different alkyl groups but the same –COOH ratios. These suggested that the surface functional groups and their compositions had a combined effect on modulating surface hydrophobicity but not surface roughness. The second part of our study was to investigate the effect of surface functional groups and their compositions on blood cascade activation and structural properties of the formed clots. It was found that surfaces with –COOH/–(CH2)3CH3 induced a faster coagulation activation than those with –COOH/–CH3 and –CH2CH3, regardless of the –COOH ratios. An increase in –COOH ratios on –COOH/–CH3 and –CH2CH3 surfaces decreased the rate of activation. Moreover, all material-coated surfaces markedly reduced the complement activation compared to uncoated glass surfaces, and the pattern of complement activation was entirely similar to that of surface-induced coagulation, suggesting there is an interaction between two cascades. The clots formed on material-coated surfaces had thicker fibrin with a tighter network at the exterior when compared to uncoated glass surfaces. Compared to the clot exteriors, thicker fibrins with a loose network were found in clot interiors. Coated surfaces resulted in more rigid clots with a significantly slower fibrinolysis after 1 h of lysis when compared to uncoated glass surfaces. Significant differences in fibrinolysis after 1 h of lysis among clots on material-coated surfaces correlated well with the differences in fibrin thickness and density at clot exterior. In addition, more growth factors were released during clot formation than during clot lysis. From an intact clot, there was a correlation between the amount of PDGF-AB release and fibrin density. Highest amount of PDGF-AB was released from clots formed on surfaces with 40% –COOH/60% –CH 3 (i.e. 65MMA). During clot lysis, the release of PDGF-AB also correlated with the fibrinolytic rate while the release of TGF-â1 was influenced by the fibrin thickness. This suggested that different clot structures led to different release profiles of growth factors in clot intact and degrading stages. We further validated whether the clots formed on material-coatings provide the microenvironment for improved bone healing by using a rabbit femoral defect model. In this pilot study, the implantation of clots formed on 65MMA coatings significantly increased new bone formation with enhanced chondrogenesis, osteoblasts activity and vascularisation, but decreased inflammatory macrophage number at the defects after 4 weeks when compared to commercial bone grafts ChronOSTM â-TCP granules. Empty defects were observed when blood clot formation was inhibited. In summary, our study demonstrated that surface functional groups and their relative ratios on material coatings synergistically modulate activation of blood cascades, resultant fibrin architecture, rigidity, susceptibility to fibrinolysis as well as growth factor release of the formed clots, which ultimately alter the healing microenvironment of injured bones.
Resumo:
Sandwich panels comprising steel facings and a polystyrene foam core are increasingly used as roof and wall claddings in buildings in Australia. When they are subjected to loads causing bending and/or axial compression, the steel plate elements of their profiled facing are susceptible to local buckling. However, when compared to panels with no foam core, they demonstrate significantly improved local buckling behaviour because they are supported by foam. In order to quantify such improvements and to validate the use of available design buckling stress formulae, an investigation using finite element analyses and laboratory experiments was carried out on steel plates that are commonly used in Australia of varying yield stress and thickness supported by a polystyrene foam core. This paper presents the details of this investigation, the buckling results and their comparison with available design buckling formulae.
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A method for forming a material comprising a metal oxide supported on a support particle comprising the steps of: (a) providing a precursor mixt. comprising a soln. contg. one or more metal cations and (i) a surfactant; or (ii) a hydrophilic polymer; said precursor mixt. further including support particles; and (b) treating the precursor mixt. from (a) above by heating to remove the surfactant or hydrophilic polymer and form metal oxide having nanosized grains, wherein at least some of the metal oxide formed in step (b) is deposited on or supported by the support particles and the metal oxide has an oxide matrix that includes metal atoms derived solely from sources other than the support particles. The disclosure and examples pertain to emission control catalysts. [on SciFinder(R)]
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The prime objective of drying is to enhance shelf life of perishable food materials. As the process is very energy intensive in nature, researchers are trying to minimise energy consumption in the drying process. In order to determine the exact amount of energy needed for drying a food product, understanding the physics of moisture distribution and bond strength of water within the food material is essential. In order understand the critical moisture content, moisture distribution and water bond strength in food material, Thermogravimetric analysis (TGA) can be properly utilised. This work has been conducted to investigate moisture distribution and water bond strength in selected food materials; apple, banana and potato. It was found that moisture distribution and water bond strength influence moisture migration from the food materials. In addition, proportion of different types of water (bound, free, surface water) has been simply identified using TGA. This study provides a better understanding of water contents and its role in drying rate and energy consumption.
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In recent years there has been a noticeable move by various public institutions, such as public service broadcasters and community media organisations, to capture and disseminate the voices and viewpoints of ‘ordinary people’ through inviting them to share stories about their lives. One of the foremost objectives of many such projects is to provide under-represented individuals and groups with an opportunity to express and represent themselves; as such, the capture and broadcast of ‘authentic voices’ is a central value. This paper discusses the notion of ‘authentic voice’, and questions the framing role of public media organisations in storytelling projects that aim to provide individuals with space for self-expression and self-representation. It considers the ways in which tensions arise on multiple levels when individuals are asked to express and represent themselves within projects and spaces that are managed by institutions. This paper begins by discussing the challenges and opportunities that arise within storytelling projects that are facilitated by public institutions and community media arts organisations, and that aim to amplify the voices of “ordinary people” (Thumim, 2009). It examines ways in which ‘voice’ is facilitated, curated, broadcast and distributed within such projects, particularly questioning the ways in which project facilitation and the curation of stories for public broadcast can both help and hinder the amplification of ‘authentic voice’. Furthermore, we seek to discuss how ‘authentic voice’ is defined, and what is involved in the process of amplification. The paper moves on to discuss a case study in order to demonstrate some of the tensions that are evident within a storytelling project that is managed by a public institution – Australia’s national broadcaster – and the ways these tensions impact upon the capture and broadcast of an ‘authentic voice’ for project participants. The Australian Broadcasting Corporation’s (ABC) ‘Heywire’ project is a storytelling competition and website that aims to ‘give voice’ to 16-22 year olds who live in rural, regional and remote parts of Australia. Looking at tensions that exist on organisational, political and philosophical levels within the Heywire project reveals a number of conflicts of interest and objectives between the institution and project participants. This leads us to question whether institutionally-managed storytelling projects can effectively support individuals to have an ‘authentic voice’, and whether struggles of aims and objectives diminish the personal benefits that people may derive from expressing and representing themselves within such projects.
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The openness and compassion implicit in the social transaction of recent philosophies of cosmopolitanism is reflected in the aims of the body of interpersonal, process-driven artworks commonly referred to as relational art. In attempting to bring art into life, specifically as a point of intervention in the lives of its spectators, the affective power required to realize the communal and participatory aims of many of these artworks is central. Relational art practices invite the individualising distinctiveness of the spectator yet ultimately seek the collective affect of the artwork’s formulated community. Like cosmopolitanism, this is a felt community where the obligatory affective investment is imagined as open and empathic built on mutual exchange and generosity. They suggest that it doesn’t matter so much what we feel about art but what and how we feel through art. The artworld’s public spheres have become increasingly affective worlds, where the artwork’s coerced and managed human relations are conceived as interstices for a more open exchange with art and each other. With reference to Sydney Biennale’s recent All My Relations exhibition, this paper will interrogate how worldly feelings are made material by the requisite emotional and aesthetic labour of feeling for and with others in relational art.
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Most civil engineering structures are formed using a number of materials that are bonded to each other with their surface-to-surface interaction playing key role on the overall response of the structure. Unfortunately these interactions are extremely variable; simplified and extremely detailed models trialed to date prove quite complex. Models that assume perfect interaction, on the other hand, predict unsafe behavior. In this paper a damage mechanics based interaction between two materials of different softening properties is developed using homogenisation approach. This paper describes the process of developing a bi-material representative volume element (RVE) using damaged homogenisation approach. The novelty in this paper is the development of non-local transient damage identification algorithm. Numerical examples prove the stability of the approach for a simplified RVE and encourage application to other shapes of RVEs.
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Material yielding is typically modeled either by plastic zone or plastic hinge methods under the context of geometric and material nonlinear finite element methods. In fire analysis of steel structures, the plastic zone method is widely used, but it requires extensively more computational efforts. The objective of this paper is to develop the nonlinear material model allowing for interaction of both axial force and bending moment, which relies on the plastic hinge method to achieve numerical efficiency and reduce computational effort. The biggest advantage of the plastic-hinge approach is its computational efficiency and easy verification by the design code formulae of the axial force–moment interaction yield criterion for beam–column members. Further, the method is reliable and robust when used in analysis of practical and large structures. In order to allow for the effect of catenary action, axial thermal expansion is considered in the axial restraint equations. The yield function for material yielding incorporated in the stiffness formulation, which allows for both axial force and bending moment effects, is more accurate and rational to predict the behaviour of the frames under fire. In the present fire analysis, the mechanical properties at elevated temperatures follow mainly the Eurocode 3 [Design of steel structures, Part 1.2: Structural fire design. European Committee for Standisation; 2003]. Example of a tension member at a steady state heating condition is modeled to verify the proposed spring formulation and to compare with results by others. The behaviour of a heated member in a highly redundant structure is also studied by the present approach.
Resumo:
Most research virtually ignores the important role of a blood clot in supporting bone healing. In this study, we investigated the effects of surface functional groups carboxyl and alkyl on whole blood coagulation, complement activation and blood clot formation. We synthesised and tested a series of materials with different ratios of carboxyl (–COOH) and alkyl (–CH3, –CH2CH3 and –(CH2)3CH3) groups. We found that surfaces with –COOH/–(CH2)3CH3 induced a faster coagulation activation than those with –COOH/– CH3 and –CH2CH3, regardless of the –COOH ratios. An increase in –COOH ratios on –COOH/–CH3 and –CH2CH3 surfaces decreased the rate of coagulation activation. The pattern of complement activation was entirely similar to that of surface-induced coagulation. All material coated surfaces resulted in clots with thicker fibrin in a denser network at the clot/material interface and a significantly slower initial fibrinolysis when compared to uncoated glass surfaces. The amounts of platelet-derived growth factor-AB (PDGF-AB) and transforming growth factor-b (TGF-b1) released from an intact clot were higher than a lysed clot. The release of PDGF-AB was found to be correlated with the fibrin density. This study demonstrated that surface chemistry can significantly influence the activation of blood coagulation and complement system, resultant clot structure, susceptibility to fibrinolysis as well as release of growth factors, which are important factors determining the bone healing process.
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Creating an authentic assessment which at once assesses competencies, scene management, communication and overall patient care is challenging in the competitive tertiary education market. Increasing student numbers and the cost of evaluating scenario based competencies serve to ensure the need for consistent objectivity and need for timely feedback to students on their performance. Objective structured clinical examination (OSCE) is currently the most flexible approach to competency based formative and summative assessment and widely used within paramedic degree programs. Students are understandably compelled to perform well and can be frustrated by not receiving timely and appropriate feedback. Increasingly a number of products aimed at providing a more efficient and paperless approach have begun to enter the market. These products, it is suggested are aimed at medicine programs and not at allied health professions and limited to one operating system and therefore ignore issues surrounding equity and accessibility. OSCE Online aims to address this gap in the market and is tailored to these disciplines. The application will provide a service that can be both tailored and standardised from a pre-written bank, depending upon requirement to fit around the needs of clinical competency assessment. Delivering authentic assessments to address student milestones in their training to become paramedics is the cornerstone of OSCE Online. By not being restricted to a specific device it will address issues of functionality, adaptability, accessibility, authenticity and importantly: transparency and accountability by producing contemporaneous data allowing issues to be easily identified and rectified.
Resumo:
This paper discusses the opportunities and challenges that arise within storytelling projects that are facilitated by public service broadcasters and that aim to amplify the voices of ‘ordinary people’. In particular, it focuses on two of the Australian Broadcasting Corporation’s current life storytelling projects: ABC Open and Heywire.
Resumo:
Shared Material on Dying is a trio/solo work commissioned by Jenny Roche and the Dublin Dance Festival in 2008 from choreographer Liz Roche. Touring widely since its creation, it continues to be a rich research environment for the interrogation by Jenny Roche of the dancer’s first-person perspective in choreographic production and performance. The research perspective drawn from the live performance of this iteration was how the exploration of the same dancing moment might be expressed from multiple perspectives by three different dancers and what this might reveal about the dancer’s inner configuring of the performance environment. Erin Manning (2009) describes the unstable and emergent moment before movement materialises as the preacceleration of the movement, when the potentialities of the gesture collapse and stabilize into form. It is this threshold of potentiality that is interesting, the moment before the dance happens when the configuring process of the dancer brings it into being. Cynthia Roses Thema (2007), after neuroscientist Antonio Damasio, writes that embodied experience is mapped as it unfolds and alters from moment to moment in line with a constantly changing internal milieu. As a performer in this piece, I explored the inner terrain of the three performers (myself included) by externalizing these inner states. This research contributed to a paper presentation at the Digital Resources for the Arts and Humanities Conference, UK 2013.
Resumo:
Insulated rail joints are designed in a similar way to butt jointed steel structural systems, the difference being a purpose made gap between the main rail members to maintain electrical insulation for the proper functioning of the track circuitry at all times of train operation. When loaded wheels pass the gap, they induce an impact loading with the corresponding strains in the railhead edges exceeding the plastic limit significantly, which lead to metal flow across the gap thereby increasing the risk of short circuiting and impeding the proper functioning of the signalling and broken rail identification circuitries, of which the joints are a critical part. The performance of insulated rail joints under the passage of the wheel loading is complex due to the presence of a number of interacting components and hence is not well understood. This paper presents a dynamic wheel-rail contact-impact modelling method for the determination of the impact loading; a brief description of a field experiment to capture strain signatures for validating the predicted impact loading is also presented. The process and the results of the characterisation of the materials from virgin, in-service and damaged insulated rail joints using neutron diffraction method are also discussed.