A novella of ideas : how interactive new media art can effectively communicate an indigenous philosophical concept

How interactive new media art can effectively communicate an indigenous philosophical concept. The sophistication and complexity of the philosophical concept concerning relationships between land and people and between people, intrinsic to the laws and customs of Australian Indigenous society, has begun to be communicated and accessed beyond the realm of anthropological and ethnological domains of Western scholarship. The exciting scope and rapid development of new media arts presents an innovative means of creating an interactive relationship with the general Australian public, addressing the urgent need for an understanding of Indigenous Australian concepts of relationship to land, and to each other, absent from Western narratives. The study is framed by an Indigenous concept of place, and relationships between land and people and between people; and explores how this concept can be clearly communicated through interactive new media arts. It involves: a creative project, the development of an interactive new media art project, a website work-in-progress titled site\sight\cite; and an exegesis, a Novella of Ideas, on the origins, influences, objectives, and potential of creative practices and processes engaged in the creative project. Research undertaken for the creative project and exegesis extended my creative practice into the use of interdisciplinary arts, expressly for the expression of philosophical concepts, consolidating 23 years experience in Indigenous community arts development. The creative project and exegesis contributes to an existing body of Indigenous work in a range of areas - including education, the arts and humanities - which bridges old and new society in Australia. In this study, old and new society is defined by the time of the initial production of art and foundations of knowledge, in the country of its origins, in Indigenous Australia dating back at least 40,000 years.

Australian media ethics regime and ethical risk management

Media organizations are simultaneously key elements of an effective democracy and, for the most part, commercial entities seeking success in the market. They play an essential role in the formation of public opinion and the influence on personal choices. Yet most of them are commercial enterprises seeking readers or viewers, advertising, favorable regulatory decisions for their media, and other assets. This creates some intrinsic difficulties and produces some sharp tensions within media ethics. In this article, we examine such tensions—in theory and practice. We then consider the feasibility of introducing an ethics regime to the media industry—a regime that would be effective in a deregulated environment in protecting public interest and social responsibility. In the article, we also outline a rationale and a methodology for the institutionalization of an acceptable and workable media ethics regime that aims to protect the integrity of the industry in a future of undoubtedly increasing commercial pressure.

A comparison of different methods to determine diffusion length in dye-sensitized solar cells

A new steady state method for determination of the electron diffusion length in dye-sensitized solar cells (DSCs) is described and illustrated with data obtained using cells containing three different types of electrolyte. The method is based on using near-IR absorbance methods to establish pairs of illumination intensity for which the total number of trapped electrons is the same at open circuit (where all electrons are lost by interfacial electron transfer) as at short circuit (where the majority of electrons are collected at the contact). Electron diffusion length values obtained by this method are compared with values derived by intensity modulated methods and by impedance measurements under illumination. The results indicate that the values of electron diffusion length derived from the steady state measurements are consistently lower than the values obtained by the non steady-state methods. For all three electrolytes used in the study, the electron diffusion length was sufficiently high to guarantee electron collection efficiencies greater than 90%. Measurement of the trap distributions by near-IR absorption confirmed earlier observations of much higher electron trap densities for electrolytes containing Li+ ions. It is suggested that the electron trap distributions may not be intrinsic properties of the TiO2 nanoparticles, but may be associated with electron-ion interactions.

Navigating iScapes : Australian youth constructing identities and social relations in a network society

This paper extends Appadurai’s notion of “scapes” to delineate what we see as “iScapes”. We contend that iScapes captures the way online technologies shape interactions that invariably filter into offline contexts, giving shape and meaning to human actions and motivations. By drawing on research on high school students’ online activities we examine the flow of iScapes they inhabit in the process of constructing identities and forming social relations.

The effect of prolonged reading on visual functions and reading performance in students with low vision

This study is the first to investigate the effect of prolonged reading on reading performance and visual functions in students with low vision. The study focuses on one of the most common modes of achieving adequate magnification for reading by students with low vision, their close reading distance (proximal or relative distance magnification). Close reading distances impose high demands on near visual functions, such as accommodation and convergence. Previous research on accommodation in children with low vision shows that their accommodative responses are reduced compared to normal vision. In addition, there is an increased lag of accommodation for higher stimulus levels as may occur at close reading distance. Reduced accommodative responses in low vision and higher lag of accommodation at close reading distances together could impact on reading performance of students with low vision especially during prolonged reading tasks. The presence of convergence anomalies could further affect reading performance. Therefore, the aims of the present study were 1) To investigate the effect of prolonged reading on reading performance in students with low vision 2) To investigate the effect of prolonged reading on visual functions in students with low vision. This study was conducted as cross-sectional research on 42 students with low vision and a comparison group of 20 students with normal vision, aged 7 to 20 years. The students with low vision had vision impairments arising from a range of causes and represented a typical group of students with low vision, with no significant developmental delays, attending school in Brisbane, Australia. All participants underwent a battery of clinical tests before and after a prolonged reading task. An initial reading-specific history and pre-task measurements that included Bailey-Lovie distance and near visual acuities, Pelli-Robson contrast sensitivity, ocular deviations, sensory fusion, ocular motility, near point of accommodation (pull-away method), accuracy of accommodation (Monocular Estimation Method (MEM)) retinoscopy and Near Point of Convergence (NPC) (push-up method) were recorded for all participants. Reading performance measures were Maximum Oral Reading Rates (MORR), Near Text Visual Acuity (NTVA) and acuity reserves using Bailey-Lovie text charts. Symptoms of visual fatigue were assessed using the Convergence Insufficiency Symptom Survey (CISS) for all participants. Pre-task measurements of reading performance and accuracy of accommodation and NPC were compared with post-task measurements, to test for any effects of prolonged reading. The prolonged reading task involved reading a storybook silently for at least 30 minutes. The task was controlled for print size, contrast, difficulty level and content of the reading material. Silent Reading Rate (SRR) was recorded every 2 minutes during prolonged reading. Symptom scores and visual fatigue scores were also obtained for all participants. A visual fatigue analogue scale (VAS) was used to assess visual fatigue during the task, once at the beginning, once at the middle and once at the end of the task. In addition to the subjective assessments of visual fatigue, tonic accommodation was monitored using a photorefractor (PlusoptiX CR03™) every 6 minutes during the task, as an objective assessment of visual fatigue. Reading measures were done at the habitual reading distance of students with low vision and at 25 cms for students with normal vision. The initial history showed that the students with low vision read for significantly shorter periods at home compared to the students with normal vision. The working distances of participants with low vision ranged from 3-25 cms and half of them were not using any optical devices for magnification. Nearly half of the participants with low vision were able to resolve 8-point print (1M) at 25 cms. Half of the participants in the low vision group had ocular deviations and suppression at near. Reading rates were significantly reduced in students with low vision compared to those of students with normal vision. In addition, there were a significantly larger number of participants in the low vision group who could not sustain the 30-minute task compared to the normal vision group. However, there were no significant changes in reading rates during or following prolonged reading in either the low vision or normal vision groups. Individual changes in reading rates were independent of their baseline reading rates, indicating that the changes in reading rates during prolonged reading cannot be predicted from a typical clinical assessment of reading using brief reading tasks. Contrary to previous reports the silent reading rates of the students with low vision were significantly lower than their oral reading rates, although oral and silent reading was assessed using different methods. Although the visual acuity, contrast sensitivity, near point of convergence and accuracy of accommodation were significantly poorer for the low vision group compared to those of the normal vision group, there were no significant changes in any of these visual functions following prolonged reading in either group. Interestingly, a few students with low vision (n =10) were found to be reading at a distance closer than their near point of accommodation. This suggests a decreased sensitivity to blur. Further evaluation revealed that the equivalent intrinsic refractive errors (an estimate of the spherical dioptirc defocus which would be expected to yield a patient’s visual acuity in normal subjects) were significantly larger for the low vision group compared to those of the normal vision group. As expected, accommodative responses were significantly reduced for the low vision group compared to the expected norms, which is consistent with their close reading distances, reduced visual acuity and contrast sensitivity. For those in the low vision group who had an accommodative error exceeding their equivalent intrinsic refractive errors, a significant decrease in MORR was found following prolonged reading. The silent reading rates however were not significantly affected by accommodative errors in the present study. Suppression also had a significant impact on the changes in reading rates during prolonged reading. The participants who did not have suppression at near showed significant decreases in silent reading rates during and following prolonged reading. This impact of binocular vision at near on prolonged reading was possibly due to the high demands on convergence. The significant predictors of MORR in the low vision group were age, NTVA, reading interest and reading comprehension, accounting for 61.7% of the variances in MORR. SRR was not significantly influenced by any factors, except for the duration of the reading task sustained; participants with higher reading rates were able to sustain a longer reading duration. In students with normal vision, age was the only predictor of MORR. Participants with low vision also reported significantly greater visual fatigue compared to the normal vision group. Measures of tonic accommodation however were little influenced by visual fatigue in the present study. Visual fatigue analogue scores were found to be significantly associated with reading rates in students with low vision and normal vision. However, the patterns of association between visual fatigue and reading rates were different for SRR and MORR. The participants with low vision with higher symptom scores had lower SRRs and participants with higher visual fatigue had lower MORRs. As hypothesized, visual functions such as accuracy of accommodation and convergence did have an impact on prolonged reading in students with low vision, for students whose accommodative errors were greater than their equivalent intrinsic refractive errors, and for those who did not suppress one eye. Those students with low vision who have accommodative errors higher than their equivalent intrinsic refractive errors might significantly benefit from reading glasses. Similarly, considering prisms or occlusion for those without suppression might reduce the convergence demands in these students while using their close reading distances. The impact of these prescriptions on reading rates, reading interest and visual fatigue is an area of promising future research. Most importantly, it is evident from the present study that a combination of factors such as accommodative errors, near point of convergence and suppression should be considered when prescribing reading devices for students with low vision. Considering these factors would also assist rehabilitation specialists in identifying those students who are likely to experience difficulty in prolonged reading, which is otherwise not reflected during typical clinical reading assessments.

Listening to late discovery adoption and donor offspring stories : adoption, ethics and implications for contemporary donor insemination practices

For most of the 20th Century a ‘closed’ system of adoption was practised throughout Australia and other modern Western societies. This ‘closed’ system was characterised by sealed records; amended birth certificates to conceal the adoption, and prohibited contact with all biological family. Despite claims that these measures protected these children from the taint of illegitimacy the central motivations were far more complex, involving a desire to protect couples from the stigma of infertility and to provide a socially acceptable family structure (Triseliotis, Feast, & Kyle, 2005; Marshall & McDonald, 2001). From the 1960s significant evidence began to emerge that many adopted children and adults were experiencing higher incidences of psychological difficulties, characterised by problems with psychological adjustment, building self-esteem and forming a secure personal identity. These difficulties became grouped under the term ‘genealogical bewilderment’. As a result, new policies and practices were introduced to try to place the best interests of the child at the forefront. These changes reflected new understandings of adoption; as not only an individual process but also as a social and relational process that continues throughout life. Secrecy and the withholding of birth information are now prohibited in the overwhelming majority of all domestic adoptions processed in Australia (Marshall & McDonald, 2001). One little known consequence of this ‘closed’ system of adoption was the significant number of children who were never told of their adoptive status. As a consequence, some have discovered or had this information disclosed to them, as adults. The first study that looked at the late discovery of genetic origins experiences was conducted by the Post Adoption Resource Centre in New South Wales in 1999. This report found that the participants in their study expressed feelings of disbelief, confusion, anger, sorrow and loss. Further, the majority of participants continued to struggle with issues arising from this intentional concealment of their genetic origins (Perl & Markham, 1999). A second and more recent study (Passmore, Feeney & Foulstone, 2007) looked at the issue of secrecy in adoptive families as part of a broader study of 144 adult adoptees. This study found that secrecy and/or lies or misinformation on the part of adoptive parents had negative effects on both personal identity and relationships with others. The authors noted that those adoptees who found out about their adoption as adults were ‘especially likely to feel a sense of betrayal’ (p.4). Over recent years, stories of secrecy and late discovery have also started to emerge from sperm donor conceived adults (Spencer, 2007; Turner & Coyle, 2000). Current research evidence shows that although a majority of couples during the donor assisted conception process indicate that they intend to tell the offspring about their origins, as many as two-thirds or more of couples continue to withhold this information from their children (Akker, 2006; Gottlieb, A. McWhinnie, 2001; Salter-Ling, Hunter, & Glover, 2001). Why do they keep this secret? Infertility involves a range of complex factors that are often left unresolved or poorly understood by those choosing insemination by donor as a form of family building (Schaffer, J. A., & Diamond, R., 1993). These factors may only impact after the child is born, when resemblance talk becomes most pronounced. Resemblance talk is an accepted form of public discourse and a social convention that legitimises the child as part of the family and is part of the process of constructing the child’s identity within the family. Couples tend to become focused on resemblance as this is where they feel most vulnerable, and the lack of resemblance to the parenting father may trigger his sense of loss (Becker, Butler, & Nachtigall, 2005).

Creative Commons : the next generation : Creative Commons licence use five years on

Since its launch in 2001, the Creative Commons open content licensing initiative has received both praise and censure. While some have touted it as a major step towards removing the burdens copyright law imposes on creativity and innovation in the digital age, others have argued that it robs artists of their rightful income. This paper aims to provide a brief overview and analysis of the practical application of the Creative Commons licences five years after their launch. It looks at how the Creative Commons licences are being used and who is using them, and attempts to identify likely motivations for doing so. By identifying trends in how this licence use has changed over time, it also attempts to rebut arguments that Creative Commons is a movement of academics and hobbyists, and has no value for traditional organisations or working artists.

Asia and the Commons : case studies 2008

A collection of case studies of individuals and organisations utilising open models in the Asia Pacific and associated regions. The case studies represent activities in nine countries, broader regions such as the Arab nations, and global efforts towards sustainability and social justice, revealing creative ways of participating in the commons. Featured are remix artists, performers, open source software programmers, film makers, collecting institutions and publishing houses focused on democracy and change, who demonstrate a diverse set of motivations to engage with the shared ideals of openness and community collaboration.

Do strategy choices matter for nascent firms? A study on effectuation and causation impacts on new ventures outcomes

Principal Topic : Nascent entrepreneurship has drawn the attention of scholars in the last few years (Davidsson, 2006, Wagner, 2004). However, most studies have asked why firms are created focussing on questions such as what are the characteristics (Delmar and Davidsson, 2000) and motivations (Carter, Gartner, Shaver & Reynolds, 2004) of nascent entrepreneurs, or what are the success factors in venture creation (Davidsson & Honig; 2003; Delmar and Shane, 2004). In contrast, the question of how companies emerge is still in its infancy. On a theoretical side, effectuation, developed by Sarasvathy (2001) offers one view of the strategies that may be at work during the venture creation process. Causation, the theorized inverse to effectuation, may be described as a rational reasoning method to create a company. After a comprehensive market analysis to discover opportunities, the entrepreneur will select the alternative with the higher expected return and implement it through the use of a business plan. In contrast, effectuation suggests that the future entrepreneur will develop her new venture in a more iterative way by selecting possibilities through flexibility and interaction with the market, affordability of loss of resources and time invested, development of pre-commitments and alliances from stakeholders. Another contrasting point is that causation is ''goal driven'' while an effectual approach is ''mean driven'' (Sarasvathy, 2001) One of the predictions of effectuation theory is effectuation is more likely to be used by entrepreneurs early in the venture creation process (Sarasvathy, 2001). However, this temporal aspect and the impact of the effectuation strategy on the venture outcomes has so far not been systematically and empirically tested on large samples. The reason behind this research gap is twofold. Firstly, few studies collect longitudinal data on emerging ventures at an early enough stage of development to avoid severe survivor bias. Second, the studies that collect such data have not included validated measures of effectuation. The research we are conducting attempts to partially fill this gap by combining an empirical investigation on a large sample of nascent and young firms with the effectuation/causation continuum as a basis (Sarasvathy, 2001). The objectives are to understand the strategies used by the firms during the creation process and measure their impacts on the firm outcomes. Methodology/Key Propositions : This study draws its data from the first wave of the CAUSEE project where 28,383 Australian households were randomly contacted by phone using a specific methodology to capture emerging firms (Davidsson, Steffens, Gordon, Reynolds, 2008). This screening led to the identification of 594 nascent ventures (i.e., firms that are not operating yet) and 514 young firms (i.e., firms that have started operating from 2004) that were willing to participate in the study. Comprehensive phone interviews were conducted with these 1108 ventures. In a likewise comprehensive follow-up 12 months later, 80% of the eligible cases completed the interview. The questionnaire contains specific sections designed to distinguish effectual and causal processes, innovation, gestation activities, business idea changes and ventures outcomes. The effectuation questions are based on the components of effectuation strategy as described by Sarasvathy (2001) namely: flexibility, affordable loss and pre-commitment from stakeholders. Results from two rounds of pre-testing informed the design of the instrument included in the main survey. The first two waves of data have will be used to test and compare the use of effectuation in the venture creation process. To increase the robustness of the results, temporal use of effectuation will be tested both directly and indirectly. 1. By comparing the use of effectuation in nascent and young firms from wave 1 to 2, we will be able to find out how effectuation is affected by time over a 12-month duration and if the stage of venture development has an impact on its use. 2. By comparing nascent ventures early in the creation process versus nascent ventures late in the creation process. Early versus late can be determined with the help of time-stamped gestation activity questions included in the survey. This will help us to determine the change on a small time scale during the creation phase of the venture. 3. By comparing nascent firms to young (already operational) firms. 4. By comparing young firms becoming operational in 2006 with those first becoming operational in 2004. Results and Implications : Wave 1 and 2 data have been completed and wave 2 is currently being checked and 'cleaned'. Analysis work will commence in September, 2009. This paper is expected to contribute to the body of knowledge on effectuation by measuring quantitatively its use and impact on nascent and young firms activities at different stages of their development. In addition, this study will also increase the understanding of the venture creation process by comparing over time nascent and young firms from a large sample of randomly selected ventures. We acknowledge the results from this study will be preliminary and will have to be interpreted with caution as the changes identified may be due to several factors and may not only be attributed to the use/not use of effectuation. Meanwhile, we believe that this study is important to the field of entrepreneurship as it provides some much needed insights on the processes used by nascent and young firms during their creation and early operating stages.

An Integrative framework of the factors affecting process model understanding : a learning perspective

Process models are used by information professionals to convey semantics about the business operations in a real world domain intended to be supported by an information system. The understandability of these models is vital to them actually being used. After all, what is not understood cannot be acted upon. Yet until now, understandability has primarily been defined as an intrinsic quality of the models themselves. Moreover, those studies that looked at understandability from a user perspective have mainly conceptualized users through rather arbitrary sets of variables. In this paper we advance an integrative framework to understand the role of the user in the process of understanding process models. Building on cognitive psychology, goal-setting theory and multimedia learning theory, we identify three stages of learning required to realize model understanding, these being Presage, Process, and Product. We define eight relevant user characteristics in the Presage stage of learning, three knowledge construction variables in the Process stage and three potential learning outcomes in the Product stage. To illustrate the benefits of the framework, we review existing process modeling work to identify where our framework can complement and extend existing studies.

The impact of distributional preferences on (experimental) markets for expert services

Theory predicts that efficiency prevails on credence goods markets if customers are able to verify which quality they receive from an expert seller. In a series of experiments with endogenous prices we observe that verifiability fails to result in efficient provision behaviour and leads to very similar results as a setting without verifiability. Some sellers always provide appropriate treatment even if own money maximization calls for over- or undertreatment. Overall our endogenous-price-results suggests that both inequality aversion and a taste for efficiency play an important role for experts’ provision behaviour. We contrast the implications of those two motivations theoretically and discriminate between them empirically using a fixed-price design. We then classify experimental experts according to their provision behaviour.

Learning approach and perception of learning context in economics education : a causality test

In the study of student learning literature, the traditional view holds that when students are faced with heavy workload, poor teaching, and content that they cannot relate to – important aspects of the learning context, they will more likely utilise the surface approach to learning due to stresses, lack of understanding and lack of perceived relevance of the content (Kreber, 2003; Lizzio, Wilson, & Simons, 2002; Ramdsen, 1989; Ramsden, 1992; Trigwell & Prosser, 1991; Vermunt, 2005). For example, in studies involving health and medical sciences students, courses that utilised student-centred, problem-based approaches to teaching and learning were found to elicit a deeper approach to learning than the teacher-centred, transmissive approach (Patel, Groen, & Norman, 1991; Sadlo & Richardson, 2003). It is generally accepted that the line of causation runs from the learning context (or rather students’ self reported data on the learning context) to students’ learning approaches. That is, it is the learning context as revealed by students’ self-reported data that elicit the associated learning behaviour. However, other research studies also found that the same teaching and learning environment can be perceived differently by different students. In a study of students’ perceptions of assessment requirements, Sambell and McDowell (1998) found that students “are active in the reconstruction of the messages and meanings of assessment” (p. 391), and their interpretations are greatly influenced by their past experiences and motivations. In a qualitative study of Hong Kong tertiary students, Kember (2004) found that students using the surface learning approach reported heavier workload than students using the deep learning approach. According to Kember if students learn by extracting meanings from the content and making connections, they will more likely see the higher order intentions embodied in the content and the high cognitive abilities being assessed. On the other hand, if they rote-learn for the graded task, they fail to see the hierarchical relationship in the content and to connect the information. These rote-learners will tend to see the assessment as requiring memorising and regurgitation of a large amount of unconnected knowledge, which explains why they experience a high workload. Kember (2004) thus postulate that it is the learning approach that influences how students perceive workload. Campbell and her colleagues made a similar observation in their interview study of secondary students’ perceptions of teaching in the same classroom (Campbell et al., 2001). The above discussions suggest that students’ learning approaches can influence their perceptions of assessment demands and other aspects of the learning context such as relevance of content and teaching effectiveness. In other words, perceptions of elements in the teaching and learning context are endogenously determined. This study attempted to investigate the causal relationships at the individual level between learning approaches and perceptions of the learning context in economics education. In this study, students’ learning approaches and their perceptions of the learning context were measured. The elements of the learning context investigated include: teaching effectiveness, workload and content. The authors are aware of existence of other elements of the learning context, such as generic skills, goal clarity and career preparation. These aspects, however, were not within the scope of this present study and were therefore not investigated.

A Knight without a Sword? The Effects of Audit Courts on Tax Morale

The intention of this paper is to analyse how audit courts affect tax morale, controlling in a multivariate analysis for a broad variety of potential factors. Switzerland, with its variety of audit-court competence among the cantons, has been analysed. With data from the ISSP [1998] (Swiss data 1999), evidence has been found that higher audit-court competence has a significantly positive effect on tax morale. Thus, the results in Switzerland suggest that in the cantons where audit courts are not just knights without swords; they help improve taxpayers' tax morale and thus citizens' intrinsic motivation to pay taxes.

In vitro cultivation of adult human chondrocytes : importance of culture system, oxygen and zonal differences

Articular cartilage exhibits limited intrinsic regenerative capacity and focal tissue defects can lead to the development of osteoarthritis (OA), a painful and debilitating loss of cartilage tissue. In Australia, 1.4 million people are affected by OA and its prevalence is increasing in line with current demographics. As treatment options are limited, new therapeutic approaches are being investigated including biological resurfacing of joints with tissue-engineered cartilage. Despite some progress in the field, major challenges remain to be addressed for large scale clinical success. For example, large numbers of chondrogenic cells are required for cartilage formation, but chondrocytes lose their chondrogenic phenotype (dedifferentiate) during in vitro propagation. Additionally, the zonal organization of articular cartilage is critical for normal cartilage function, but development of zonal structure has been largely neglected in cartilage repair strategies. Therefore, we hypothesised that culture conditions for freshly isolated human articular chondrocytes from non-OA and OA sources can be improved by employing microcarrier cultures and a reduced oxygen environment and that oxygen is a critical factor in the maintenance of the zonal chondrocyte phenotype. Microcarriers have successfully been used to cultivate bovine chondrocytes, and offer a potential alternative for clinical expansion of human chondrocytes. We hypothesised that improved yields can be achieved by propagating human chondrocytes on microcarriers. We found that cells on microcarriers acquired a flattened, polygonal morphology and initially proliferated faster than monolayercultivated cells. However, microcarrier cultivation over four weeks did not improve growth rates or the chondrogenic potential of non-OA and OA human articular chondrocytes over conventional monolayer cultivation. Based on these observations, we aimed to optimise culture conditions by modifying oxygen tension, to more closely reflect the in vivo environment. We found that propagation at 5% oxygen tension (moderate hypoxia) did not improve proliferation or redifferentiation capacity of human osteoarthritic chondrocytes. Moderate hypoxia increased the expression of chondrogenic markers during redifferentiation. However, osteoarthritic chondrocytes cultivated on microcarriers exhibited lower expression levels of chondrogenic surface marker proteins and had at best equivalent redifferentiation capacities compared to monolayer-cultured cells. This suggests that monolayer culture with multiple passaging potentially selects for a subpopulation of cells with higher differentiation capacity, which are otherwise rare in osteoarthritic, aged cartilage. However, fibroblastic proteins were found to be highly expressed in all cultures of human osteoarthritic chondrocytes indicating the presence of a high proportion of dedifferentiated, senescent cells with a chondrocytic phenotype that was not rescued by moderate hypoxia. The different zones of cartilage support chondrocyte subpopulations, which exhibit characteristic protein expression and experience varying oxygen tensions. We, therefore, hypothesised that oxygen tension affects the zonal marker expression of human articular chondrocytes isolated from the different cartilage layers. We found that zonal chondrocytes maintained these phenotypic differences during in vitro cultivation. Low oxygen environments favoured the expression of the zonal marker proteoglycan 4 in superficial cells, most likely through the promotion of chondrogenesis. The putative zonal markers clusterin and cartilage intermediate layer protein were found to be expressed by all subpopulations of human osteoarthritic chondrocytes ex vivo and, thus, may not be reliable predictors of in vitro stratification using these clinically relevant cells. The findings in this thesis underline the importance of considering low oxygen conditions and zonal stratification when creating native-like cartilaginous constructs. We have not yet found the right cues to successfully cultivate clinically-relevant human osteoarthritic chondrocytes in vitro. A more thorough understanding of chondrocyte biology and the processes of chondrogenesis are required to ensure the clinical success of cartilage tissue engineering.

An ecology of centre-based child care

The studies in the thesis were derived from a program of research focused on centre-based child care in Australia. The studies constituted an ecological analysis as they examined proximal and distal factors which have the potential to affect children's developmental opportunities (Bronfenbrenner, 1979). The project was conducted in thirty-two child care centres located in south-east Queensland. Participants in the research included staff members at the centres, families using the centres and their children. The first study described the personal and professional characteristics of one hundred and forty-four child care workers, as well as their job satisfaction and job commitment. Factors impinging on the stability of care afforded to children were examined, specifically child care workers' intentions to leave their current position and actual staff turnover at a twelve month follow-up. This is an ecosystem analysis (Bronfenbrenner & Crouter, 1983), as it examined the world of work for carers; a setting not directly involving the developing child, but which has implications for children's experiences. Staff job satisfaction was focused on working with children and other adults, including parents and colleagues. Involvement with children was reported as being the most rewarding aspect of the work. This intrinsic satisfaction was enough to sustain caregivers' efforts to maintain their employment in child care programs. It was found that, while improving working conditions may help to reduce turnover, it is likely that moderate turnover rates will remain as child care staff work in relatively small centres and they leave in order to improve career prospects. Departure from a child care job appeared to be as much about improving career opportunities or changing personal circumstances, as it was about poor wages and working conditions. In the second study, factors that influence maternal satisfaction with child care arrangements were examined. The focus included examination of the nature and qualities of parental interaction with staff. This was a mesosystem analysis (Bronfenbrenner & Crouter, 1983), as it considered the links between family and child care settings. Two hundred and twenty-two questionnaires were returned from mothers whose children were enrolled in the participating centres. It was found that maternal satisfaction with child care encompassed the domains of child-centred and parent-centred satisfaction. The nature and range of responses in the quantitative and qualitative data indicated that these parents were genuinely satisfied with their children's care. In the prediction of maternal satisfaction with child care, single parents, mothers with high role satisfaction, and mothers who were satisfied with the frequency of staff contact and degree of supportive communication had higher levels of satisfaction with their child care arrangements. The third study described the structural and process variations within child care programs and examined program differences for compliance with regulations and differences by profit status of the centre, as a microsystem analysis (Bronfenbrenner, 1979). Observations were made in eighty-three programs which served children from two to five years. The results of the study affirmed beliefs that nonprofit centres are superior in the quality of care provided, although this was not to a level which meant that the care in for-profit centres was inadequate. Regulation of structural features of child care programs, per se, did not guarantee higher quality child care as measured by global or process indicators. The final study represented an integration of a range of influences in child care and family settings which may impact on development. Features of child care programs which predict children's social and cognitive development, while taking into account child and family characteristics, were identified. Results were consistent with other research findings which show that child and family characteristics and child care quality predict children's development. Child care quality was more important to the prediction of social development, while family factors appeared to be more predictive of cognitive/language development. An influential variable predictive of development was the period of time which the child had been in the centre. This highlighted the importance of the stability of child care arrangements. Child care quality features which had most influence were global ratings of the qualities of the program environment. However, results need to be interpreted cautiously as the explained variance in the predictive models developed was low. The results of these studies are discussed in terms of the implications for practice and future research. Considerations for an expanded view of ecological approaches to child care research are outlined. Issues discussed include the need to generate child care research which is relevant to social policy development, the implications of market driven policies for child care services, professionalism and professionalisation of child care work, and the need to reconceptualise child care research when the goal is to develop greater theoretical understanding about child care environments and developmental processes.