997 resultados para 134-831A


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This manuscript took a 'top down' approach to understanding survival of inhabitant cells in the ecosystem bone, working from higher to lower length and time scales through the hierarchical ecosystem of bone. Our working hypothesis is that nature “engineered” the skeleton using a 'bottom up' approach,where mechanical properties of cells emerge from their adaptation to their local me-chanical milieu. Cell aggregation and formation of higher order anisotropic struc- ture results in emergent architectures through cell differentiation and extracellular matrix secretion. These emergent properties, including mechanical properties and architecture, result in mechanical adaptation at length scales and longer time scales which are most relevant for the survival of the vertebrate organism [Knothe Tate and von Recum 2009]. We are currently using insights from this approach to har-ness nature’s regeneration potential and to engineer novel mechanoactive materials [Knothe Tate et al. 2007, Knothe Tate et al. 2009]. In addition to potential applications of these exciting insights, these studies may provide important clues to evolution and development of vertebrate animals. For instance, one might ask why mesenchymal stem cells condense at all? There is a putative advantage to self-assembly and cooperation, but this advantage is somewhat outweighed by the need for infrastructural complexity (e.g., circulatory systems comprised of specific differentiated cell types which in turn form conduits and pumps to overcome limitations of mass transport via diffusion, for example; dif-fusion is untenable for multicellular organisms larger than 250 microns in diameter. A better question might be: Why do cells build skeletal tissue? Once cooperatingcells in tissues begin to deplete local sources of food in their aquatic environment, those that have evolved a means to locomote likely have an evolutionary advantage. Once the environment becomes less aquarian and more terrestrial, self-assembled organisms with the ability to move on land might have conferred evolutionary ad-vantages as well. So did the cytoskeleton evolve several length scales, enabling the emergence of skeletal architecture for vertebrate animals? Did the evolutionary advantage of motility over noncompliant terrestrial substrates (walking on land) favor adaptations including emergence of intracellular architecture (changes in the cytoskeleton and upregulation of structural protein manufacture), inter-cellular con- densation, mineralization of tissues, and emergence of higher order architectures?How far does evolutionary Darwinism extend and how can we exploit this knowl- edge to engineer smart materials and architectures on Earth and new, exploratory environments?[Knothe Tate et al. 2008]. We are limited only by our ability to imagine. Ultimately, we aim to understand nature, mimic nature, guide nature and/or exploit nature’s engineering paradigms without engineer-ing ourselves out of existence.

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Introduction Queensland has the highest ambulance utilisation (150 per 1000 population) in Australia and growing 4.4% annually. However, the impact of gender and age on utilisation is unknown. Methods & Materials Data on ambulance utilisation from Queensland Ambulance Service for the period 2002-2009 were analysed. Results Between 2002 and 2009, the number of ambulance patients per 1000 population increased overall by 17% (females) and 18% (males). The utilisation rate remained highest among the elderly but grew differently across age groups. For females, the rates were 55% (0-14yo), 73% (15-29yo), 38% (30-44yo), 22% (45-59yo), -9% (60-74yo) and -6% (75,+ yo); for males they were 48%, 59%, 38%, 17%, -13% and -2% respectively. Within the same age groups and period, the population adjusted number of males per 100 females (M:F ratio) changed from 134 to 128 (-5% growth), 98 to 91 (-8%), 101 to 100 (-0.4%), 115 to 111 (-3%), 114 to 108 (-5%) and 106 to 111 (4%). Conclusion Understanding the impact of patients’ demographic profiles on service utilisation and broader effects on the emergency health system is imperative for policy-making, demand management, designing public health campaigns and health promotions. Gender and age characteristics of ambulance users in Queensland appear to be changing most noticeably in the youngest and oldest groups. Physical and mental health, attitudinal, lifestyle, parenting, financial and socio-cultural reasons may account for these trends, but little evidence exists. A theoretical framework will be discussed to contextualise the findings.

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The objective was to understand the influence of the surface roughness of lactose carriers on the adhesion and dispersion of salmeterol xinafoate (SX) from interactive mixtures. The surface roughness of lactose carriers was determined by confocal microscopy. Particle images and adhesion forces between SX and lactose particles were determined by Atomic Force Microscopy. The dispersion of SX (2.5%) from interactive mixtures with lactose was determined using a twin-stage impinger (TSI) with a Rotahaler® at an airflow rate of 60L/min. SX was analysed using a validated HPLC assay. The RMS Rq of lactose carriers ranged from 0.93-2.84μm, the Fine Particle Fraction (FPF) of SX ranged between 4 and 24 percent and average adhesion force between a SX and lactose particles ranged between 49 and 134 nN. No direct correlation was observed between the RMS Rq of lactose carriers and either the FPF of SX for the interactive mixtures or the adhesion force of a SX on the lactose particles; however, the presence of fine lactose associated with the carrier surface increased the FPF of SX. Dispersion through direct SX detachment from the carrier surface was not consistent with the poor correlations described and was more likely to occur through complex particulate interactions involving fine lactose.

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In light of the changing nature of contemporary workplaces, this chapter attempts to identify employer expectations and the associated skills required to workers to function effectively in such workplaces. Workers are required to participate in informed discussion about their specific jobs and to contribute to the overall development of organisations. This requires deep understanding of domain-specific knowledge, which at times can be very complex. Workers are also required to take responsibility for their actions and are expected to be flexible so that they can be deployed to other related jobs depending on demand. Finally, workers are expected to be pro-active, be able to anticipate situations and continuously update their knowledge to address new situations. This chapter discusses the nature of knowledge and skills that will facilitate the above qualities.

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The business of helping children to grow up as ‘custodians’, or ‘future managers’ of the Murray-Darling Basin is not simple, and that single sources of information and ways of seeing the environment are not enough. Children (and adults) need to be able to relate individually, emotionally and aesthetically to their places if they are to learn to love them. However, they also need access to a variety of ways of thinking and seeing those same places if they are to be able to take action to sustain them – action that inevitably involves forms of communication with their fellow citizens. This chapter documents the writing and art program Special Forever, with its focus on communications, as an important intervention into promoting eco-social sustainability.

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The ethical conduct of professionals has been the focus of increasing scrutiny over the past several decades as members of the public, the media, professional bodies, and legislative authorities have struggled to define ethical behaviour in times of governmental change, increasing internationalisation, globalised communications, threats of terrorism, and the challenges of developments in science and medicine (e.g., Demmke & Bossaert, 2004). National governments and transnational bodies have responded to these concerns about ethics and corruption through measures such as the United Nations Convention Against Corruption (United Nations Office on Drugs and Crime, 2004), Transparency International’s annual corruption index (2010) and Queensland’s Public Sector Ethics Act 1994 (Queensland Parliament 1994). Similarly, academic interest in ethics and its application across a range of domains(e.g., business, health care, social welfare, criminal justice, law, journalism, defence, environment, and media) has also increased. To illustrate, in 1993, a non-partisan, non-profit national umbrella organisation, the Australian Association for Professional and Applied Ethics, was formed following a conference concerned with the teaching of ethics (http://www.arts.unsw.edu.au./aapae/about_aapae/about_aapae.htm), while a recent review of the Excellence in Research for Australian rankings of national and international academic journals revealed that 16 journals related to ethics had received the top ratings of A* or A (Australian Research Council, 2009). In this chapter we examine professional ethics and argue, with specific reference to the context of pre-service teacher education, that Service-learning is one way of enhancing emerging professionals’ understanding of ethics.

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The Northern Territory Government's Working Future: Outstations/Homelands (2009) policy statement gives effect to the Council of Australian Government's Closing the Gap policy on Indigenous housing and remote service delivery. These policies mark a radical shift in public policy that winds back the outstations and homelands movement that began in the 1970's. This paper examines Indigenous homelands policy and considers whether these policies are consistent with the Indigenous human rights and in particular the United Nations Declaration on the Rights of Indigenous Peoples (2007), which Australia endorsed in 2009. The author argues that the current homelands policy breaches a number of Indigenous human rights and promotes assimiliation by forcing Indigenous Australians to relocate to access basic services such as health, housing and education. As a consequence these policies are counter-intuitive to the overall Closing the Gap goals of improving Indigenous health outcomes because they fail to take into account the importance of country and culture to Indigenous wellbeing. She concludes that Australian governments need to formulate a homelands policy that is consistent with Indigenous human rights and in particular the right of self determination, enjoyment of culture and protection against forced assimilation.

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Tony Fitzgerald’s visionary leap was to see beyond localised, individual wrongdoing. He suggested remedies that were systemic, institutionalised, and directed at underlying structural problems that led to corruption. His report said ‘the problems with which this Inquiry is concerned are not merely associated with individuals, but are institutionalized and related to attitudes which have become entrenched’ (Fitzgerald Report 1989, 13). His response was to suggest an enmeshed system of measures to not only respond reactively to future corruption, but also to prevent its recurrence through improved integrity systems. In the two decades since that report the primary focus of corruption studies and anti-corruption activism has remained on corruption at the local level or within sovereign states. International activism was largely directed at co-ordinating national campaigns and to use international instruments to make these campaigns more effective domestically. This reflects the broader fact that, since the rise of the nation state, states have comprised the majority of the largest institutional actors and have been the most significant institution in the lives of most individuals. This made states the ‘main game in town’ for the ‘governance disciplines’ of ethics, law, political science and economics.

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The stochastic simulation algorithm was introduced by Gillespie and in a different form by Kurtz. There have been many attempts at accelerating the algorithm without deviating from the behavior of the simulated system. The crux of the explicit τ-leaping procedure is the use of Poisson random variables to approximate the number of occurrences of each type of reaction event during a carefully selected time period, τ. This method is acceptable providing the leap condition, that no propensity function changes “significantly” during any time-step, is met. Using this method there is a possibility that species numbers can, artificially, become negative. Several recent papers have demonstrated methods that avoid this situation. One such method classifies, as critical, those reactions in danger of sending species populations negative. At most, one of these critical reactions is allowed to occur in the next time-step. We argue that the criticality of a reactant species and its dependent reaction channels should be related to the probability of the species number becoming negative. This way only reactions that, if fired, produce a high probability of driving a reactant population negative are labeled critical. The number of firings of more reaction channels can be approximated using Poisson random variables thus speeding up the simulation while maintaining the accuracy. In implementing this revised method of criticality selection we make use of the probability distribution from which the random variable describing the change in species number is drawn. We give several numerical examples to demonstrate the effectiveness of our new method.