980 resultados para ANTIMICROBIAL ACTION
Resumo:
This paper presents the theory and practice of the Futures Action Model (FAM). FAM has been in development for over a decade, in a number of contexts and iterations. It is a creative methodology that uses a variety of concepts and tools to guide participants through the conception and modeling of enterprises, services, social innovations and projects in the context of emerging futures. It is used to generate strategic options that people can utilise to build opportunities for value creation as they move into the future. This paper details examples in its development, and provides theoretical and practical guidelines for educators and business facilitators to use the FAM system in their own workplaces.
Resumo:
BACKGROUND: Burn sepsis is a leading cause of mortality and morbidity in patients with major burns. The use of topical antimicrobial agents has helped improve the survival of these patients. Silvazine (Sigma Pharmaceuticals, Melbourne, Australia) (1% silver sulphadiazine and 0.2% chlorhexidine digluconate) is used exclusively in Australasia, and there is no published study on its cytotoxicity. This study compared the relative cytotoxicity of Silvazine with 1% silver sulphadiazine (Flamazine (Smith & Nephew Healthcare, Hull, UK)) and a silver-based dressing (Acticoat (Smith & Nephew Healthcare, Hull, UK)). METHODS: Dressings were applied to the centre of culture plates that were then seeded with keratinocytes at an estimated 25% confluence. The plates were incubated for 72 h and culture medium and dressings then removed. Toluidine blue was added to stain the remaining keratinocytes. Following removal of the dye, the plates were photographed under standard conditions and these digital images were analysed using image analysis software. Data was analysed using Student's t-test. RESULTS: In the present study, Silvazine is the most cytotoxic agent. Seventy-two hour exposure to Silvazine in the present study results in almost no keratinocyte survival at all and a highly statistically significant reduction in cell survival relative to control, Acticoat and Flamazine (P<0.001, P<0.01, P<0.01, respectively). Flamazine is associated with a statistically significant reduction in cell numbers relative to control (P<0.05), but is much less cytotoxic than Silvazine (P<0.005). CONCLUSION: In this in-vitro study comparing Acticoat, Silvazine and Flamazine, Silvazine shows an increased cytotoxic effect, relative to control, Flamazine and Acticoat. An in-vivo study is required to determine whether this effect is carried into the clinical setting.
Resumo:
This thesis is a work-in-progress that articulates my research journey based on the development of a curriculum innovation in environmental education. This journey had two distinct, but intertwined phases: action research based fieldwork, conducted collaboratively, to create a whole school approach to environmental education curriculum planning; and a phase of analysis and reflection based on the emerging findings, as I sought to create personal "living educational theory" about change and innovation. A key stimulus for the study was the perceived theory-practice gap in environmental education, which is often presented in the literature as a criticism of teachers for failing to achieve the values and action objectives of critical environmental education. Hence, many programs and projects are considered to be superficial and inconsequential in terms of their ability to seriously address environmental issues. The intention of this study was to work with teachers in a project that would be an exemplar of critical environmental education. This would be in the form of a whole school "learnscaping" curriculum in a primary school whereby the schoolgrounds would be utilised for interdisciplinary critical environment education. Parallel with the three cycles of action research in this project, my research objectives were to identify and comment upon the factors that influence the generation of successful educational innovation. It was anticipated that the project would be a collaboration involving me, as researcher-facilitator, and many of the teachers in the school as active participants. As the project proceeded through its action cycles, however, it became obvious that the goal of developing a critical environmental education curriculum, and the use of highly participatory processes, were unrealistic. Institutional and organisational rigidities in education generally, teachers' day-to-day work demands, and the constant juggle of work, family and other responsibilities for all participants acted as significant constraints. Consequently, it became apparent that the learnscaping curriculum would not be the hoped-for exemplar. Progress was slow and, at times, the project was in danger of stalling permanently. While the curriculum had some elements of critical environmental education, these were minor and not well spread throughout the school. Overall, the outcome seemed best described as a "small win"; perhaps just another example of the theory-practice gap that I had hoped this project would bridge. Towards the project's end, however, my continuing reflection led to an exploration of chaos/complexity theory which gave new meaning to the concept of a "small win". According to this theory, change is not the product of linear processes applied methodically in purposeful and diligent ways, but emerges from serendipitous events that cannot be planned for, or forecast in advance. When this perspective of change is applied to human organisations - in this study, a busy school - the context for change is recognised not as a stable, predictable environment, but as a highly complex system where change happens all the time, cannot be controlled, and no one can be really sure where the impacts might lead. This so-called "butterfly effect" is a central idea of this theory where small changes or modifications are created - the effects of which are difficult to know, let alone determine - and which can have large-scale impacts. Allied with this effect is the belief that long term developments in an organisation that takes complexity into account, emerge by spontaneous self-organising evolution, requiring political interaction and learning in groups, rather than systematic progress towards predetermined goals or "visions". Hence, because change itself and the contexts of change are recognised as complex, chaos/complexity theory suggests that change is more likely to be slow and evolutionary - cultural change - rather than fast and revolutionary where the old is quickly ushered out by radical reforms and replaced by new structures and processes. Slow, small-scale changes are "normal", from a complexity viewpoint, while rapid, wholesale change is both unlikely and unrealistic. Therefore, the frustratingly slow, small-scale, imperfect educational changes that teachers create - including environmental education initiatives - should be seen for what they really are. They should be recognised as successful changes, the impacts of which cannot be known, but which have the potential to magnify into large-scale changes into the future. Rather than being regarded as failures for not meeting critical education criteria, "small wins" should be cause for celebration and support. The intertwined phases of collaborative action research and individual researcher reflection are mirrored in the thesis structure. The first three chapters, respectively, provide the thesis overview, the literature underpinning the study's central concern, and the research methodology. Chapters 4, 5, and 6 report on each of the three action research cycles of the study, namely Laying the Groundwork, Down to Work!, and The Never-ending Story. Each of these chapters presents a narrative of events, a literature review specific to developments in the cycle, and analysis and critique of the events, processes and outcomes of each cycle. Chapter 7 provides a synthesis of the whole of the study, outlining my interim propositions about facilitating curriculum change in schools through action research, and the implications of these for environmental education.
Resumo:
The integration of separate, yet complimentary, cortical pathways appears to play a role in visual perception and action when intercepting objects. The ventral system is responsible for object recognition and identification, while the dorsal system facilitates continuous regulation of action. This dual-system model implies that empirically manipulating different visual information sources during performance of an interceptive action might lead to the emergence of distinct gaze and movement pattern profiles. To test this idea, we recorded hand kinematics and eye movements of participants as they attempted to catch balls projected from a novel apparatus that synchronised or de-synchronised accompanying video images of a throwing action and ball trajectory. Results revealed that ball catching performance was less successful when patterns of hand movements and gaze behaviours were constrained by the absence of advanced perceptual information from the thrower's actions. Under these task constraints, participants began tracking the ball later, followed less of its trajectory, and adapted their actions by initiating movements later and moving the hand faster. There were no performance differences when the throwing action image and ball speed were synchronised or de-synchronised since hand movements were closely linked to information from ball trajectory. Results are interpreted relative to the two-visual system hypothesis, demonstrating that accurate interception requires integration of advanced visual information from kinematics of the throwing action and from ball flight trajectory.
Resumo:
This research introduces a novel dressing for burn wounds, containing silver nanoparticles in hydrogels for infected burn care. The 2-acrylamido-2-methylpropane sulfonic acid sodium salt hydrogels containing silver nanoparticles have been prepared via ultraviolet radiation. The formation of silver nanoparticles was monitored by surface plasmon bands and transmission electron microscopy. The concentration of silver nitrate loaded in the solutions slightly affected the physical properties and mechanical properties of the neat hydrogel. An indirect cytotoxicity study found that none of the hydrogels were toxic to tested cell lines. The measurement of cumulative release of silver indicated that 70%–82% of silver was released within 72 hr. The antibacterial activities of the hydrogels against common burn pathogens were studied and the results showed that 5 mM silver hydrogel had the greatest inhibitory activity. The results support its use as a potential burn wound dressing.
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This case study examines the way in which Knowledge Unlatched is combining collective action and open access licenses to encourage innovation in markets for specialist academic books. Knowledge Unlatched is a not for profit organisation that has been established to help a global community of libraries coordinate their book purchasing activities more effectively and, in so doing, to ensure that books librarians select for their own collections become available for free for anyone in the world to read. The Knowledge Unlatched model is an attempt to re-coordinate a market in order to facilitate a transition to digitally appropriate publishing models that include open access. It offers librarians an opportunity to facilitate the open access publication of books that their own readers would value access to. It provides publishers with a stable income stream on titles selected by libraries, as well as an ability to continue selling books to a wider market on their own terms. Knowledge Unlatched provides a rich case study for researchers and practitioners interested in understanding how innovations in procurement practices can be used to stimulate more effective, equitable markets for socially valuable products.
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SIC and DRS are related proteins present in only four of the more than 200 Streptococcus pyogenes emm-types. These proteins inhibit complement mediated lysis and/or the activity of certain antimicrobial peptides. A gene encoding a homologue of these proteins, herein called DrsG, has been identified in the related bacterium Streptococcus dysgalactiae subsp equisimilis (SDSE). Here we show that geographically dispersed isolates representing 14 of 50 emm-types examined possess variants of drsG. However not all isolates within the drsG-positive emm-types possess the gene. Sequence comparisons also reveal a high degree of conservation in different SDSE emm-types. To examine the biological activity of DrsG, recombinant versions of two major DrsG variants, DrsGS and DrsGL, were expressed and purified. Western blot analysis using antisera raised to these proteins demonstrated both variants to be expressed and secreted into culture supernatant. Unlike SIC, but similar to DRS, DrsG does not inhibit complement mediated lysis. However, like both SIC and DRS, DrsG is a ligand of the cathelcidin LL-37 and is inhibitory to its bactericidal activity in in vitro assays. The greatest similarity between DrsG and DRS/SIC is found in the signal sequence at the amino terminus and proline rich domains in the C-terminal half of the protein. Conservation of prolines in this latter region also suggests these residues are important in the biology of this family of proteins. This is the first report demonstrating the activity of an AMP inhibitory protein in SDSE. These results also suggest that inhibition of AMP activity is the primary function of this family of proteins. The acquisition of complement inhibitory activity of SIC may reflect its continuing evolution.
Resumo:
UV-vis photodissociation action spectroscopy is becoming increasingly prevalent because of advances in, and commercial availability of, ion trapping technologies and tunable laser sources. This study outlines in detail an instrumental arrangement, combining a commercial ion-trap mass spectrometer and tunable nanosecond pulsed laser source, for performing fully automated photodissociation action spectroscopy on gas-phase ions. The components of the instrumentation are outlined, including the optical and electronic interfacing, in addition to the control software for automating the experiment and performing online analysis of the spectra. To demonstrate the utility of this ensemble, the photodissociation action spectra of 4-chloroanilinium, 4-bromoanilinium, and 4-iodoanilinium cations are presented and discussed. Multiple photoproducts are detected in each case and the photoproduct yields are followed as a function of laser wavelength. It is shown that the wavelength-dependent partitioning of the halide loss, H loss, and NH3 loss channels can be broadly rationalized in terms of the relative carbon-halide bond dissociation energies and processes of energy redistribution. The photodissociation action spectrum of (phenyl)Ag-2 (+) is compared with a literature spectrum as a further benchmark.
Resumo:
The ultraviolet photodissociation of gas-phase N-methylpyridinium ions is studied at room temperature using laser photodissociation mass spectrometry and structurally diagnostic ion-molecule reaction kinetics. The C5H5N-CH3+ (m/z 94), C5H5N-CD3+ (m/z 97), and C5D5N-CH3+(m/z 99) isotopologues are investigated, and it is shown that the N-methylpyridinium ion photodissociates by the loss of methane in the 36 000 - 43 000 cm(-1) (280 - 230 nm) region. The dissociation likely occurs on the ground state surface following internal conversion from the SI state. For each isotopologue, by monitoring the photofragmentation yield as a function of photon wavenumber, a broad vibronically featured band is recorded with origin (0-0) transitions assigned at 38 130, 38 140 and 38 320 cm(-1) for C5H5N-CH3+ C5H5N-CD3+ and C5D5N-CH3+, respectively. With the aid of quantum chemical calculations (CASSCF(6,6)/aug-cc-pVDZ), most of the observed vibronic detail is assigned to two in-plane ring deformation modes. Finally, using ion-molecule reactions, the methane coproduct at m/z 78 is confirmed as a 2-pyridinylium ion.
Resumo:
Structural investigations of large biomolecules in the gas phase are challenging. Herein, it is reported that action spectroscopy taking advantage of facile carbon-iodine bond dissociation can be used to examine the structures of large molecules, including whole proteins. Iodotyrosine serves as the active chromophore, which yields distinctive spectra depending on the solvation of the side chain by the remainder of the molecule. Isolation of the chromophore yields a double featured peak at ∼290 nm, which becomes a single peak with increasing solvation. Deprotonation of the side chain also leads to reduced apparent intensity and broadening of the action spectrum. The method can be successfully applied to both negatively and positively charged ions in various charge states, although electron detachment becomes a competitive channel for multiply charged anions. In all other cases, loss of iodine is by far the dominant channel which leads to high sensitivity and simple data analysis. The action spectra for iodotyrosine, the iodinated peptides KGYDAKA, DAYLDAG, and the small protein ubiquitin are reported in various charge states. © 2012 American Chemical Society.
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This edition of ALARj has a focus on the contribution of action learning and action research to the development of community services, particularly nonprofits. The landscape of community services has been changing rapidly in recent decades, and can be typified by the notion of complexity. Complexity in the nature of issues that services seek to respond to, complexity in the policy environment and systems of support that have tended to silo and compartmentalise problems and people, and complexity in the institutional location non-profit services occupy in ‘helping’ those who are seen as ‘in need’ or marginalised. In addition to being typified by complexity the environment in which community services are located is dynamic, undergoing profound and ongoing change as neo-liberal approaches to understanding and responding to human need, which emphasise the individualisation of risk, and market principles such as choice, competition and innovation, drive social policy. How can long held values of empowerment, care, inclusivity and benefit to individuals and communities have expression in community services as they grapple with the challenges of being viable and relevant in such a dynamically changing environment? This edition brings together a range of contributions which speak to these challenges. The thematic through these is that processes are needed which engage services and communities in ongoing processes of inquiry about how they can best proceed in contexts typified by complexity and change. Action learning and action research can provide processes of this character.
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Discontinuity between prior-to-school and school sectors in Australia reflects an historical, philosophical and pedagogical schism. This is most evident as children transition from one sector to the other. However, contemporary international research, alongside an intensive focus on policy and practice in early years education has challenged many of the taken-for-granted assumptions that perpetuate this rift. Drawing on data collected in a recent action research project, we present evidence of how a group of primary school kindergarten teachers define differences between orientation and transition programs, understand the importance of transition and how they position themselves in this process. The absence of Australian policy mandating and guiding the work of teachers across sectors is a significant factor perpetuating discontinuity in transition practices between prior–to-school and school sectors.
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This paper investigates the teaching and learning of fractions to Indigenous adult learners in a Civil Construction Certificate Course. More specifically it explores why the use of materials is critical to building knowledge and understanding. This focus is important for two reasons. First, it allows for considerations of a trainer’s approach for teaching fractions and, second it provides insights into how adult learners can be supported with representing their practical experiences of fractions to make generalisation thus building on their knowledge and learning experiences. The paper draws on teaching episodes from an Australian Research Council funded Linkage project that investigates how mathematics is taught and learned in Certificate Courses, here, Certificate 11 in Civil Construction. Action research and decolonising methods (Smith, 1999) were used to conduct the research. Video excerpts which feature one trainer and three students are analysed and described. Findings from the data indicate that adult learners need to be supported with materials to assist with building their capacity to know and apply understandings of fractions in a range of contexts, besides construction. Without materials and where fractions are taught via pen and paper tasks, students are less likely to retain and apply fraction ideas to their Certificate Course. Further they are less likely to understand decimals because of limited understanding of fractions.
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In most art exhibitions, the creative part of the exhibition is assumed to be the artworks on display. But for the Capricornia Arts Mob’s first collective art exhibition in Rockhampton during NAIDOC Week in 2012, the process of developing the exhibition became the focus of creative action learning and action research. In working together to produce a multi-media exhibition, we learned about the collaborative processes and time required to develop a combined exhibition. We applied Indigenous ways of working – including yarning, cultural respect, cultural protocols, mentoring young people, providing a culturally safe working environment and sharing both time and food – to develop our first collective art exhibition. We developed a process that allowed us to ask deep questions, engage in a joint journey of learning, and develop our collective story. This paper explores the processes that the Capricornia Arts Mob used to develop the exhibition for NAIDOC 2012.