242 resultados para Interfacial tension
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This research explores the function of entrepreneurship in nonprofit art museums. Traditionally, entrepreneurship literature features debates on customer orientation and innovation. This paper reviews a tension in entrepreneurship: the relationship between limited funding and the need to innovate in nonprofit art museums. The paper develops a construct by which to explain the structure of entrepreneurship in nonprofit art museums in Australia and New Zealand since 1975. From this discussion, different strategies and tensions are highlighted that nonprofit art museum directors have used. The dynamics are explored in ten large art museums and the managerial implications are developed.
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Collaborative user-led content creation by online communities, or produsage (Bruns 2008), has generated a variety of useful and important resources and other valuable outcomes, from open source software through the Wikipedia to a variety of smaller-scale, specialist projects. These are often seen as standing in an inherent opposition to commercial interests, and attempts to develop collaborations between community content creators and commercial partners have had mixed success rates to date. However, such tension between community and commerce is not inevitable, and there is substantial potential for more fruitful exchanges and collaboration. This article contributes to the development of this understanding by outlining the key underlying principles of such participatory community processes and exploring the potential tensions which could arise between these communities and their potential external partners. It also sketches out potential approaches to resolving them.
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Australian women make decisions about return to paid work and care for their child within a policy environment that presents mixed messages about maternal employment and child care standards. Against this background an investigation of first-time mothers’ decision-making about workforce participation and child care was undertaken. Four women were studied from pregnancy through the first postnatal year using interview and diary methods. Inductive analyses identified three themes, all focused on dimensions of family security: financial security relating to family income, emotional security relating to child care quality, and pragmatic security relating to child care access. The current policy changes that aim to increase child care quality standards in Australia present a positive step toward alleviating family insecurities but are insufficient to alleviate the evidently high levels of tension between workforce participation and family life experienced by women transitioning back into the workforce in Australia.
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Nanowires (NWs) have attracted intensive researches owing to the broad applications that arise from their remarkable properties. Over the last decade, immense numerical studies have been conducted for the numerical investigation of mechanical properties of NWs. Among these numerical simulations, the molecular dynamics (MD) plays a key role. Herein we present a brief review on the current state of the MD investigation of nanowires. Emphasis will be placed on the FCC metal NWs, especially the Cu NWs. MD investigations of perfect NWs’ mechanical properties under different deformation conditions including tension, compression, torsion and bending are firstly revisited. Following in succession, the studies for defected NWs including the defects of twin boundaries (TBs) and pre-existing defects are discussed. The different deformation mechanism incurred by the presentation of defects is explored and discussed. This review reveals that the numerical simulation is an important tool to investigate the properties of NWs. However, the substantial gaps between the experimental measurements and MD results suggest the urgent need of multi-scale simulation technique.
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Purpose - It is ironic that in stressful economic times, when new ideas and positive behaviors could be most valuable, employees may not speak up, leading to reduced employee participation, less organizational learning, less innovation and less receptiveness to change. The supervisor is the organization’s first line of defense against a culture of silence and towards a culture of openness. This research asks what helps supervisors to hear prosocial voice and notice defensive silence. Design/methodology/approach - We conducted a cross-sectional field study of 142 supervisors. Findings - Our results indicate that prosocial voice is increased by supervisor tension and trust in employees, while defensive silence is increased by supervisor tension but reduced by unionization of employees and trust in employees. This indicates that, as hypothesized by others, voice and silence are orthogonal and not opposites of the same construct. Research limitations/implications - The data is measured at one point in time, and further longitudinal study would be helpful to further understand the phenomena. Practical implications - This research highlights the potential for supervisors in stressful situations to selectively hear voice and silence from employees. Originality/value - This study adds to our knowledge of prosocial voice and defensive silence by testing supervisors’ perceptions of these constructs during difficult times. It provides valuable empirical insights to a literature dominated by conceptual non-empirical papers. Limited research on silence might reflect how difficult it is to study such an ambiguous and passive construct as silence (often simply viewed as a lack of speech). also contribute to trust literature by identifying its role in increasing supervisor’s perceptions of prosocial voice and reducing perceptions of defensive silence.
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There is evidence that contact with the natural environment and green space promotes good health. It is also well known that participation in regular physical activity generates physical and psychological health benefits. The authors have hypothesised that ‘green exercise’ will improve health and psychological well-being, yet few studies have quantified these effects. This study measured the effects of 10 green exercise case studies (including walking, cycling, horse-riding, fishing, canal-boating and conservation activities) in four regions of the UK on 263 participants. Even though these participants were generally an active and healthy group, it was found that green exercise led to a significant improvement in self-esteem and total mood disturbance (with anger-hostility, confusion-bewilderment, depression-dejection and tension-anxiety all improving post-activity). Self-esteem and mood were found not to be affected by the type, intensity or duration of the green exercise, as the results were similar for all 10 case studies. Thus all these activities generated mental health benefits, indicating the potential for a wider health and well-being dividend from green exercise. Green exercise thus has important implications for public and environmental health, and for a wide range of policy sectors.
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Flexible tubular structures fabricated from solution electrospun fibers are finding increasing use in tissue engineering applications. However it is difficult to control the deposition of fibers due to the chaotic nature of the solution electrospinning jet. By using non-conductive polymer melts instead of polymer solutions the path and collection of the fiber becomes predictable. In this work we demonstrate the melt electrospinning of polycaprolactone in a direct writing mode onto a rotating cylinder. This allows the design and fabrication of tubes using 20 μm diameter fibers with controllable micropatterns and mechanical properties. A key design parameter is the fiber winding angle, where it allows control over scaffold pore morphology (e.g. size, shape, number and porosity). Furthermore, the establishment of a finite element model as a predictive design tool is validated against mechanical testing results of melt electrospun tubes to show that a lesser winding angle provides improved mechanical response to uniaxial tension and compression. In addition, we show that melt electrospun tubes support the growth of three different cell types in vitro and are therefore promising scaffolds for tissue engineering applications.
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Over the last twenty years, the use of open content licenses has become increasingly and surprisingly popular. The use of such licences challenges the traditional incentive-based model of exclusive rights under copyright. Instead of providing a means to charge for the use of particular works, what seems important is mitigating against potential personal harm to the author and, in some cases, preventing non-consensual commercial exploitation. It is interesting in this context to observe the primacy of what are essentially moral rights over the exclusionary economic rights. The core elements of common open content licences map somewhat closely to continental conceptions of the moral rights of authorship. Most obviously, almost all free software and free culture licences require attribution of authorship. More interestingly, there is a tension between social norms developed in free software communities and those that have emerged in the creative arts over integrity and commercial exploitation. For programmers interested in free software, licence terms that prohibit commercial use or modification are almost completely inconsistent with the ideological and utilitarian values that underpin the movement. For those in the creative industries, on the other hand, non-commercial terms and, to a lesser extent, terms that prohibit all but verbatim distribution continue to play an extremely important role in the sharing of copyright material. While prohibitions on commercial use often serve an economic imperative, there is also a certain personal interest for many creators in avoiding harmful exploitation of their expression – an interest that has sometimes been recognised as forming a component of the moral right of integrity. One particular continental moral right – the right of withdrawal – is present neither in Australian law or in any of the common open content licences. Despite some marked differences, both free software and free culture participants are using contractual methods to articulate the norms of permissible sharing. Legal enforcement is rare and often prohibitively expensive, and the various communities accordingly rely upon shared understandings of acceptable behaviour. The licences that are commonly used represent a formalised expression of these community norms and provide the theoretically enforceable legal baseline that lends them legitimacy. The core terms of these licences are designed primarily to alleviate risk in sharing and minimise transaction costs in sharing and using copyright expression. Importantly, however, the range of available licences reflect different optional balances in the norms of creating and sharing material. Generally, it is possible to see that, stemming particularly from the US, open content licences are fundamentally important in providing a set of normatively accepted copyright balances that reflect the interests sought to be protected through moral rights regimes. As the cost of creation, distribution, storage, and processing of expression continues to fall towards zero, there are increasing incentives to adopt open content licences to facilitate wide distribution and reuse of creative expression. Thinking of these protocols not only as reducing transaction costs but of setting normative principles of participation assists in conceptualising the role of open content licences and the continuing tensions that permeate modern copyright law.
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Background. Digital information is increasingly becoming available on all aspects of the urban landscape, anywhere and any time. Physical objects (c.f. the Internet of Things) and people (c.f. the Social Web) are increasingly infused with actuators, sensors and tagged with a wealth of digital information. Urban Informatics explores these emerging digital layers of the city. However, very little is known about the challenges and new opportunities that these developments may offer to road users. As we gradually spend more time using our mobile devices as well as our car, the tension between appeasing our craving for connectedness and road safety requirements grow farther apart. Objective. The aims of this paper are to identify (a) new opportunities that Urban Informatics research can offer to our future cars and (b) potential benefits to road safety. Methods. 14 Urban Informatics research experts were grouped into seven teams of two to participate in a guided ideation (idea creation) workshop in a driving simulator. They were immersed into different driving scenarios to brainstorm innovative Urban Informatics applications in different driving contexts. This qualitative study was then evaluated in the context of road safety. Outcomes. There is a lack of articulation between Urban Informatics and Road Safety research. Several Urban Informatics applications (e.g., to enhance social interaction between people in urban environments) may provide benefits, rather than threats, towards road safety, provided they are implemented ergonomically and safely. Conclusions. This research initiates a much-needed dialogue between Urban Informatics and Road Safety disciplines, in the context of Intelligent Transport Systems, before the fast approaching digital wave invades our cars. The dialogue will help to avoid driver distraction issues similar to mobile phones use in cars. As such, it provides valuable information for future regulators and policy makers in charge of shaping our future road transport landscape.
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This article discusses the importance of aesthetic recognition and branding for Chinese fashion designers as prerequisites for their successful positioning in a globalized marketplace. Fundamental to this process is the communication of their aesthetic in their branding process. In addition, the emergence of fashion designers of Asian-American descent who align their creative vision with a globally mainstream audience has created momentum for the new generation of mainland Chinese designers. Chinese creativity is moving to center stage as the country’s role as a leading consumer market with brands of domestic origin strengthens. Thus the aim of this article is to uncover the tension between what is, on the one hand, the need to embrace a global market, and, on the other, the desire to create the elements of a distinctly Chinese brand through aesthetic references to Chinese culture and iconography. We argue that one core element of branding is reference to heritage and tradition. Therefore to satisfy an increasingly sophisticated Chinese consumer, Chinese designers need to be able to incorporate these elements into a characteristic and well-promoted personal vision.
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The central purpose of this chapter is to address the tension between legal and medical discourses within the coronial/medico-legal system. In the context of a death investigation, medical expertise, manifest through the knowledge gained in an internal autopsy, is positioned as contributing the more valuable facts of the case, especially when contrasted with the evidence gathered at the scene of the death. We challenge this taken for granted understanding of medical knowledge in three ways: first, we examine the aspects of the history, philosophy and consequences of the processes by which the medical model gained its current dominance; second, we challenge the assumption that internal autopsy adds value to the death investigation, by utilising data from our own research in Australia; and finally, we engage with the debate about the purpose of a coronial/medico-legal investigation and role of an internal autopsy within that system.
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Recent research has described the restructuring of particles upon exposure to organic vapours; however, as yet hypotheses able to explain this phenomenon are limited. In this study, a range of experiments were performed to explore different hypotheses related to carbonaceous particle restructuring upon exposure to organic and water vapours, such as: the effect of surface tension, the role of organics in flocculating primary particles, as well as the ability of vapours to “wet” the particle surface. The change in mobility diameter (dm) was investigated for a range carbonaceous particle types (diesel exhaust, petrol exhaust, cigarette smoke, candle smoke, particles generated in a heptane/toluene flame, and wood smoke particles) exposed to different organic (heptane, ethanol, and dimethyl sulfoxide/water (1:1 vol%) mixture) and water vapours. Particles were first size-selected and then bubbled through an impinger (bubbler) containing either an organic solvent or water, where particles trapped inside rising bubbles were exposed to saturated vapours of the solvent in the impinger. The size distribution of particles was simultaneously measured upstream and downstream from the impinger. A size-dependent reduction in dm was observed when bubbling diesel exhaust, particles generated in a heptane/toluene flame, and candle smoke particles through heptane, ethanol and a dimethyl sulfoxide/water (1:1 vol %) mixture. In addition, the size distributions of particles bubbled through an impinger were broader. Moreover, an increase of the geometric standard deviation (σ) of the size distributions of particles bubbled through an impinger was also found to be size-dependent. Size-dependent reduction in dm and an increase of σ indicate that particles undergo restructuring to a more compact form, which was confirmed by TEM analysis. However, bubbling of these particles through water did not result in a size-dependent reduction in dm, nor in an increase of σ. Cigarette smoke, petrol exhaust, and wood smoke particles did not result in any substantial change in dm, or σ, when bubbled through organic solvents or water. Therefore, size-dependent reduction in the dm upon bubbling through organic solvents was observed only for particles that had a fractal-like structure, whilst particles that were liquid or were assumed to be spherical did not exhibit any reduction in dm. Compaction of fractal-like particles was attributed to the ability of condensing vapours to efficiently wet the particles. Our results also show that the presence of an organic layer on the surface of fractal-like particles, or the surface tension of the condensed liquid do not influence the extent of compaction.
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Globalization stimulated demand for transnational higher education. However, little is known about how transnational programs can facilitate knowledge transfer between the partner universities—something that is often implied in the partnership arrangement. For the purpose of this paper transnational programs will be limited to dual degree programs between Indonesian and Australian universities, which, in recent years have been rising. Nevertheless, the discussion and synthesis may have value to other transnational programs. Situating the knowledge transfer in the wider context of globalization of higher education and the current reforms in Indonesian education, the paper acknowledges the tension between the need to generate revenue and the ideals of facilitating knowledge transfer and capacity development for Indonesian universities. Drawing on a detailed review of research findings in the business and education sector literature, this paper presents a conceptual framework that may be used to analyze knowledge transfer between Indonesian and Australian universities. Such investigations delineate the significant drivers underlying transnational programs for supporting knowledge transfer. The proposed framework incorporates the types of knowledge, knowledge transfer mechanisms, and the processes. It also considers how the inter-university antecedents may affect the potential for knowledge transfer between the universities. A discussion of how the framework may be used to implemented knowledge transfer concludes this paper.
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Regenerative medicine-based approaches for the repair of damaged cartilage rely on the ability to propagate cells while promoting their chondrogenic potential. Thus, conditions for cell expansion should be optimized through careful environmental control. Appropriate oxygen tension and cell expansion substrates and controllable bioreactor systems are probably critical for expansion and subsequent tissue formation during chondrogenic differentiation. We therefore evaluated the effects of oxygen and microcarrier culture on the expansion and subsequent differentiation of human osteoarthritic chondrocytes. Freshly isolated chondrocytes were expanded on tissue culture plastic or CultiSpher-G microcarriers under hypoxic or normoxic conditions (5% or 20% oxygen partial pressure, respectively) followed by cell phenotype analysis with flow cytometry. Cells were redifferentiated in micromass pellet cultures over 4 weeks, under either hypoxia or normoxia. Chondrocytes cultured on tissue culture plastic proliferated faster, expressed higher levels of cell surface markers CD44 and CD105 and demonstrated stronger staining for proteoglycans and collagen type II in pellet cultures compared with microcarrier-cultivated cells. Pellet wet weight, glycosaminoglycan content and expression of chondrogenic genes were significantly increased in cells differentiated under hypoxia. Hypoxia-inducible factor-3alpha mRNA was up-regulated in these cultures in response to low oxygen tension. These data confirm the beneficial influence of reduced oxygen on ex vivo chondrogenesis. However, hypoxia during cell expansion and microcarrier bioreactor culture does not enhance intrinsic chondrogenic potential. Further improvements in cell culture conditions are therefore required before chondrocytes from osteoarthritic and aged patients can become a useful cell source for cartilage regeneration.
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BACKGROUND: Cell shape and tissue architecture are controlled by changes to junctional proteins and the cytoskeleton. How tissues control the dynamics of adhesion and cytoskeletal tension is unclear. We have studied epithelial tissue architecture using 3D culture models and found that adult primary prostate epithelial cells grow into hollow acinus-like spheroids. Importantly, when co-cultured with stroma the epithelia show increased lateral cell adhesions. To investigate this mechanism further we aimed to: identify a cell line model to allow repeatable and robust experiments; determine whether or not epithelial adhesion molecules were affected by stromal culture; and determine which stromal signalling molecules may influence cell adhesion in 3D epithelial cell cultures. METHODOLOGY/PRINCIPAL FINDINGS: The prostate cell line, BPH-1, showed increased lateral cell adhesion in response to stroma, when grown as 3D spheroids. Electron microscopy showed that 9.4% of lateral membranes were within 20 nm of each other and that this increased to 54% in the presence of stroma, after 7 days in culture. Stromal signalling did not influence E-cadherin or desmosome RNA or protein expression, but increased E-cadherin/actin co-localisation on the basolateral membranes, and decreased paracellular permeability. Microarray analysis identified several growth factors and pathways that were differentially expressed in stroma in response to 3D epithelial culture. The upregulated growth factors TGFβ2, CXCL12 and FGF10 were selected for further analysis because of previous associations with morphology. Small molecule inhibition of TGFβ2 signalling but not of CXCL12 and FGF10 signalling led to a decrease in actin and E-cadherin co-localisation and increased paracellular permeability. CONCLUSIONS/SIGNIFICANCE: In 3D culture models, paracrine stromal signals increase epithelial cell adhesion via adhesion/cytoskeleton interactions and TGFβ2-dependent mechanisms may play a key role. These findings indicate a role for stroma in maintaining adult epithelial tissue morphology and integrity.