997 resultados para Different electrolytes


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Numerous challenges remain in the successful clinical translation of cell-based therapies for musculoskeletal tissue repair, including the identification of an appropriate cell source and a viable cell delivery system. The aim of this study was to investigate the attachment, colonization, and osteogenic differentiation of two stem cell types, human mesenchymal stem cells (hMSCs) and human amniotic fluid stem (hAFS) cells, on electrospun nanofiber meshes. We demonstrate that nanofiber meshes are able to support these cell functions robustly, with both cell types demonstrating strong osteogenic potential. Differences in the kinetics of osteogenic differentiation were observed between hMSCs and hAFS cells, with the hAFS cells displaying a delayed alkaline phosphatase peak, but elevated mineral deposition, compared to hMSCs. We also compared the cell behavior on nanofiber meshes to that on tissue culture plastic, and observed that there is delayed initial attachment and proliferation on meshes, but enhanced mineralization at a later time point. Finally, cell-seeded nanofiber meshes were found to be effective in colonizing three-dimensional scaffolds in an in vitro system. This study provides support for the use of the nanofiber mesh as a model surface for cell culture in vitro, and a cell delivery vehicle for the repair of bone defects in vivo.

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This chapter reports on research work that aims to overcome some limitations of conventional community engagement for urban planning. Adaptive and human-centred design approaches that are well established in human-computer interaction (such as personas and design scenarios) as well as creative writing and dramatic character development methods (such as the Stanislavsky System and the Meisner Technique) are yet largely unexplored in the rather conservative and long-term design context of urban planning. Based on these approaches, we have been trialling a set of performance based workshop activities to gain insights into participants’ desires and requirements that may inform the future design of apartments and apartment buildings in inner city Brisbane. The focus of these workshops is to analyse the behaviour and lifestyle of apartment dwellers and generate residential personas that become boundary objects in the cross-disciplinary discussions of urban design and planning teams. Dramatisation and embodied interaction of use cases form part of the strategies we employed to engage participants and elicit community feedback.

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Background: There is no global definition of a heatwave because local acclimatisation and adaptation influence the impact of extreme heat. Even at a local level there can be multiple heatwave definitions, based on varying temperature levels or time periods. We investigated the relationship between heatwaves and health outcomes using ten different heatwave definitions in Brisbane, Australia. ---------- Methodology/Principal Findings: We used daily data on climate, air pollution, and emergency hospital admissions in Brisbane between January 1996 and December 2005; and mortality between January 1996 and November 2004. Case-crossover analyses were used to assess the relationship between each of the ten heatwave definitions and health outcomes. During heatwaves there was a statistically significant increase in emergency hospital admissions for all ten definitions, with odds ratios ranging from 1.03 to 1.18. A statistically significant increase in the odds ratios of mortality was also found for eight definitions. The size of the heat-related impact varied between definitions.---------- Conclusions/Significance Even a small change in the heatwave definition had an appreciable effect on the estimated health impact. It is important to identify an appropriate definition of heatwave locally and to understand its health effects in order to develop appropriate public health intervention strategies to prevent and mitigate the impact of heatwaves.

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There is a current requirement for universities to prepare graduates who are skilled in practical as well as theoretical knowledge of the workplace. It is argued in this paper that assessment, as integral to the teaching/learning process, should also relate to the real world context of the workplace, in that students are able to transform, use and apply the knowledge that they learn into these contexts. While assessment authentic for students in a university setting is often a difficult task for lecturers. This paper discusses three different learning contexts that involved different assessment experiences linked in some way to real world learning and application of the theory. The results of the trial indicated that as contexts became close to a real world experience, the sustainability of the assessment became more problematic. While acknowledging the difficulty of these practices, it is suggested that there is a need for a continuous cycle of evaluation amid some creative and innovative approaches to assessment practice.

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There have been significant improvements in toric soft contact lens design over the past decade. Data from our international contact lens prescribing survey were mined to assess recent trends in toric soft contact lens fitting. This survey was conducted by sending up to 1000 survey forms to contact lens fitters in Australia, Canada, Japan, the Netherlands, Norway, the UK and the USA each year between 2000 and 2009. Practitioners were asked to record data relating to the first 10 contact lens fits or refits performed after receiving the forms and to return them to us for analysis. The data revealed a gradual increase in the extent of toric soft lens fitting this century. Excluding Japan – which had a consistently low rate of soft toric lens fitting over the survey period – soft toric lenses now represent over 35% of all soft lenses prescribed; it can be assumed that, on average (and again excluding Japan), all cases of astigmatism 0.75 D or less remains uncorrected among contact lens wearers. Toric lenses are fitted more to those who are older, full-time wearers and reusable lens wearers, and less to those wearing silicone hydrogel and extended wear lenses.

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This paper analyzes effects of different practice task constraints on heart rate (HR) variability during 4v4 smallsided football games. Participants were sixteen football players divided into two age groups (U13, Mean age: 12.4±0.5 yrs; U15: 14.6±0.5). The task consisted of a 4v4 sub-phase without goalkeepers, on a 25x15 m field, of 15 minutes duration with an active recovery period of 6 minutes between each condition. We recorded players’ heart rates using heart rate monitors (Polar Team System, Polar Electro, Kempele, Finland) as scoring mode was manipulated (line goal: scoring by dribbling past an extended line; double goal: scoring in either of two lateral goals; and central goal: scoring only in one goal). Subsequently, %HR reserve was calculated with the Karvonen formula. We performed a time-series analysis of HR for each individual in each condition. Mean data for intra-participant variability showed that autocorrelation function was associated with more short-range dependence processes in the “line goal” condition, compared to other conditions, demonstrating that the “line goal” constraint induced more randomness in HR response. Relative to inter-individual variability, line goal constraints demonstrated lower %CV and %RMSD (U13: 9% and 19%; U15: 10% and 19%) compared with double goal (U13: 12% and 21%; U15: 12% and 21%) and central goal (U13: 14% and 24%; U15: 13% and 24%) task constraints, respectively. Results suggested that line goal constraints imposed more randomness on cardiovascular stimulation of each individual and lower inter-individual variability than double goal and central goal constraints.

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The purpose of this thesis is to examine the influence of ethnic cultural values on the relationship of role demands and the work-family balance (WFB) experience. Past studies have found that the demands from work and family roles have a different impact on the work-family experience in people of different ethnicity. Researchers attribute these results to the cultural differences across the groups. However, there has been no empirical support for these assumptions because most past studies did not explicitly measure the cultural dimension in their design. Therefore, although studies have found ethnic differences in work-family experience, as cultural variables were not measured, it cannot be determined whether these differences were due to the differing ethnic groups’ cultural styles. The present thesis is set up to address this limitation in the literature, employing the Malay and Chinese ethnic groups in Malaysia as the study samples. The investigation consisted of pilot interviews and two survey studies. The interviews were carried out to establish the perception of WFB by target participants of a non-western nation. The first survey served to identify whether the Malay and Chinese ethnic groups residing under the same economic and social systems vary in their perceptions of work and family roles. The second survey tests the research model empirically, that is, whether cultural values moderate the relationship between role demands and WFB and if these moderation effects vary across ethnic groups. From the interviews, the results indicated that work-family experience is not a universal experience, but is partly culture-specific. Specifically, in the case of Malaysia, WFB is very much observed from the role obligation perspective. In particular, balance is perceived when work duties and household affairs are both adequately fulfilled. On the other hand, the conceptualisation of WFB in terms of role satisfaction and role interference also emerged in the interviews, suggesting the universality of these constructs across cultures. The findings from Survey One indicated that participants of different ethnicities in this study do not differ greatly in their perceptions regarding their participation in work and family roles. Generally, these participants revealed the less traditional attitudes towards women’s participation in work and family roles. However, variations were observed between the two groups in terms of reasons for working, spouses’ preferences towards their employment, and the extent to which their work role is perceived to impede their normative role performance in the household. Despite these differences, the Malay and Chinese ethnic groups showed more similarities than differences in their perceptions of work and family. The findings from Survey Two, which tested the research model, produced mixed results. On the whole, the results showed that the cultural dimensions examined in this study (i.e. collectivism, work identity and family identity) did influence the relationship between role demands and WFB experience, thus providing empirical evidence for the assumption in the literature that the relationship between role demand and work-family experience is moderated by cultural values. Most importantly, support was found for the proposition that these moderation effects vary between the Malay and Chinese ethnic groups. Moreover, this study also found evidence that Malays and Chinese differ significantly on collectivism and work identity cultural dimensions where Malays are found to be more collectivist than the Chinese, while work identity is stronger in the Chinese than in the Malays. There is no difference in the levels of family identity between the two groups. Of all the three moderators, work identity was deemed the most important because many of the supported hypotheses pertained to the work identity moderating effects. In contrast, family identity does not seem to have much moderating influence on role demand-WFB relationships, while the results for the collectivism moderator are mixed. As such, although not conclusive, it can be deduced that variations in the effects of role demand on work-family experience across ethnicity are a result of the groups’ cultural differences, thereby supporting the assumption in the literature.

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Molecular dynamics (MD) simulations have been carried out to investigate the defect’s effect on the mechanical properties of copper nanowire with different crystallographic orientations, under tensile deformation. Three different crystallographic orientations have been considered. The deformation mechanism has been carefully discussed. It is found that the Young’s modulus is insensitive to the defect, even when the nanowire’s crystallographic orientation is different. However, due to the defect’s effect, the yield strength and yield strain appear a large decrease. The defects have played a role of dislocation sources, the slips or stacking faults are first generated around the locations of the defects. The necking locations have also been affected by different defects. Due to the surface defect, the plastic deformation has received a large influence for the <001>/{110} and <110> orientated nanowires, and a relative small influence is seen for the <111> nanowire.

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Young children shift meanings across multiple modes long before they have mastered formal writing skills. In a digital age, children are socialised into a wide range of new digital media conventions in the home, at school, and in community-based settings. This article draws on longitudinal classroom research with a culturally diverse cohort of eight-year old children, to advance new understandings about children’s engagement in transmediation in the context of digital media creation. The author illuminates three key principles of transmediation using multimodal snapshots of storyboard images, digital movie frames, and online comics. Insights about transmediation are developed through dialogue with the children about their thought processes and intentions for their multimedia creations.

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The aim of the study is to establish optimum building aspect ratios and south window sizes of residential buildings from thermal performance point of view. The effects of 6 different building aspect ratios and eight different south window sizes for each building aspect ratio are analyzed for apartments located at intermediate floors of buildings, by the aid of the computer based thermal analysis program SUNCODE-PC in five cities of Turkey: Erzurum, Ankara, Diyarbakir, Izmir, and Antalya. The results are evaluated in terms of annual energy consumption and the optimum values are driven. Comparison of optimum values and the total energy consumption rates is made among the analyzed cities.