966 resultados para medium effect


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There is an abundance of books available on the topic of motherhood and mothering; the majority of these books focus on the vulnerability of babies and young children and the motherwork such vulnerability demands. In particular they focus on what it is right to do in the interests of the child, and particularly his or her growth and development. Such a focus is consistent in Western culture with modern moral frameworks where understandings of goodness have been assimilated to dimensions of human action rather than dimensions of human being, selfhood, or specific forms of life. As Charles Taylor has observed, much modern moral philosophy has focused =on what it is right to do rather than the nature of the good life‘ (1989, 13). The master narratives of motherhood and the prevailing social discourses of intensive1 and sacrificial2 mothering exemplify this view as such narratives and discourses depict =what mothers are expected to do [and] how mothers are supposed to be‘ (Nelson 2001, 140). From such infant/child-focused accounts a canonical maternal identity can be discerned; arguably, it is a restricted one. The majority of these books fail to address questions related to what it means be a mother in particular situated, existing, living realities. For instance, ask a mother with young children what being a mother means to her and she may speak of the challenges she faces balancing paid employment and her role as a mother, or the impact of the demands being made on her time and energy. However, ask a mother with young adult-children3 what being a mother means to her and she may speak in similar tones, but she may also speak in differing tones. For example, a "mature" mother may speak of the "empty nest", the "crowded house" and/or "its revolving front door". She may speak of issues related to the vulnerability of the long term marriage, elder care, or grandparenting, or even disillusionment and disenchantment. The purpose of this research is to explore the identity challenges and prospects of some mothers with young adult-children aged between 18 and 30 years of age in twenty-first century Australia. In interpreting the identity challenges and prospects this particular cohort of mothers encounter in their ordinary, everyday living, a diverse and particular range of maternal experiences.my own included5.have been traced, along with the social and ethical meanings ascribed in them. With an understanding and appreciation of voice as the medium which connects one's inner and outer worlds, this research illuminates the plurality of voices and the multiple layers of meaning in each of these mother's particular living and existing realities. Specifically, this research addresses the narrowly constructed, canonical maternal identity through a critical exploration and reflection on stories, shared in a research context, of the living realities of a group of self-identified "mature", middle-class, Australian mothers with children aged between 18 and 30 years of age6. By appraising the broader familial, historical, social, cultural, institutional, and, importantly, moral contexts in which these mothers are situated, 'thick descriptions' (Geertz 1973, 27)7 of maternal identities, and the challenges and prospects these mothers are negotiating, are provided. In terms of its ethical orientation, the frameworks which support and frame this research reject, repudiate and contest (Nelson 2001) the reduction of ethical concerns to individual or intellectual problems or dilemmas to be solved through the application of a theory derived from reasoned thinking. In dismissing deductive and =theoretical-juridical‘8 approaches, the individualistic orientation entrenched in contemporary Western moral thinking, expressed in the notion of '"what ought I to do" when faced with a problem, issue or dilemma of practical urgency' (Isaacs & Massey 1994, 1), is simultaneously rejected, repudiated and contested (Nelson 2001). In countering such understandings, this research reorients us to the illumination and articulation of who it is good to be, for each of these mothers, in allegiance with those goods which guide and inspire her orientations towards living a good life—a life which embraces and enhances the flourishing of herself and her significant others. With an understanding and appreciation that 'mind is never free of precommitment[—t]here is no innocent eye, nor is there one that penetrates aboriginal reality' (Bruner 1987, 32), this thesis is written with the voices of other interlocutors9. These interlocutors include the voices of my research participants whom I refer to as "research interlocutors", my textual "friends" — those scholars whose work resonates strongly with my orientations—as well as the myriad other voices that speak to mothers, for mothers and about mothers, such as those found in popular and mainstream press and culture. Sometimes these voices resonate; other times dissonance may be heard. In situating this research within these complementary frameworks, this research invites readers to join with me in considering, appreciating and appraising the narrow construction of maternal identity. I seek for this engagement, like the engagements with my research interlocutors, to be 'a meeting of voices, an authentic dialogue that is inclusive of the voices of all concerned participants' (Isaacs 2001, 6). I hope that the voices in this thesis resonate with yours (although, at times, you may feel some dissonance) and that together we can draw closer to the accounting, re-counting and re-stor(y)ing of maternal identities; like concentric circles of witness, the dialogue, ...will thus be expanded rippling into corners where one might both imagine, and least expect. Possibilities, then, are vast; the future exciting (Smith 2007, 397). This research is also shaped and guided by maternal scholarship, a relatively new field of inquiry known as 'motherhood studies' (O'Reilly 2011, xvii) which has its origins within the broader terrain of feminist scholarship. As a work of maternal scholarship, this thesis draws upon and continues the tradition of examining motherhood as it is experienced 'in a social context, as embedded in a political institution: in feminist terms' (Rich 1995, ix). It values mothers, their experiences, their stories, their lives. As such, this research is oriented towards 'matricentric feminism', a particular form of feminist inquiry, politics and theory which is consistent with and receptive to feminist frameworks of care and equal rights (O‘Reilly 2011, 25). A number of complementary conceptual frameworks have been engaged in this research with the thesis presented in three parts: the pre-figurative, configurative and re-configurative. As my particular living experiences provided the initial motivation for this research, an account of the challenges I experienced as a mother with young adult-children are outlined as a Prelude to this thesis. Attention then turns to Part One – Pre-figuring Maternal Identities in which the contextual, conceptual and methodological foundations underpinning this research are explored and outlined. In Chapter One, the prevailing cultural narratives and social discourses supporting and shaping the construction of the canonical maternal identity are outlined. Next, in setting the scholarly context, the critiques — arising from feminist and maternal scholarship — of motherhood as a patriarchal institution, mothering as experience, and mothering as work, are explored. As this research engaged with participants who are embedded in particular middle-class, heterosexual, familial and cultural structures, an exploration of family life cycle theory and main stream media accounts are also incorporated. The terrain in which "mature" mothering within an Australian context is experienced is also outlined, including the notions of "empty nests" and "crowded houses", grandparenting, elder care and women's midlife transition. Chapter Two gives an account of the conceptual ontological, ethical, identity and narrative frameworks underpinning this research. In setting the context for rich interpretations, the characteristics of being human10 are outlined before attention turns to our embodiment and embeddedness in our shared human condition11. From this point, attention then turns to understanding the moral form of human living12. In appreciating the vulnerability inherent in our shared human condition, the ways in which we may experience trouble in our lives is noted. The framing of identity constitution13 as complex, multi-faceted, relationally negotiated and composed is then outlined, followed by an understanding of why narrative is a valuable interpretive tool for interpreting and understanding human experiences. This chapter concludes with an appreciation of the ethical significance of storytelling. The research methodology is then outlined in Chapter Three. The rationale underpinning the adoption of the narrative interviewing technique of in-depth interviewing is explored. In exploring these methodological frameworks, the recruitment and interview processes involved in gathering and interpreting the recorded transcripts of ten Australian mothers with young adult-children are outlined. The method of analysis known as the Listening Guide14 best complements the multi-layered, pluri-vocal nature of narrative accounting. The final section of Chapter Three outlines The Guide, with one mother's recorded transcript used to illustrate this method's step-by-step process. Having gathered an understanding and appreciation of the pluri-vocal, multi-layered nature of narrative and identity constitution, the tone of this thesis changes in Part Two . Configuring Maternal Identities. This section consists of Chapters Four and Five and seeks to find meaning in, and make sense of, the differences and commonalities across these particular accounts. Chapter Four explores the living realities of four Australian mothers with young adult-children: Poppy, Honey, Lily and Heather. In presenting a thick description of these mothers' situated realities, the frameworks.the familial, social, cultural, historical and institutional backgrounds.which have supported and shaped each mother's experiences are illuminated. Simultaneously revealed through these particular accounts are the plurality of goods focusing and moving each mother to the moral form of life, a life of meaning and purpose. The harms challenging some mothers' moral motivations are also revealed in this chapter. Specifically illustrated in Chapter Four are the unique and qualitative differences of particular maternal identity configurations. Chapter Five reveals the commonalities amongst all of the research interlocutors' accounts. This chapter contests the individualistic orientation of many contemporary accounts of motherhood which are aimed at defining or contesting what a "good" mother ought to do. By turning away from such individualistic orientations, the chapter does not seek to define 'the content of obligation' (Taylor 1989, 3) but rather seeks to illuminate and articulate a richer, deeper understanding and appreciation of maternal be-ing and be-coming - that is, who it is good to be, for each of these mothers - in allegiance with those goods that focus and inspire her moral motivations. Part Three - Re-Configuring Maternal Identities, which is comprised of Chapter Six, draws this thesis to a close. In this final chapter, the preconceptions, conditions and aspirations for this mother-centred account of the living realities of a small, local cohort of mothers are reiterated. The insights gathered from the rich, descriptive accounts are illuminated and articulated, and the chapter closes with some suggestions for future research. In a Postlude, I reflect on how this research has been a transformative learning experience in my own life.an experience in which I have been able to not only deeply understand and appreciate the challenges and disorientation I was experiencing but also to identify and reorient my stance in relation to the good. In a practical sense, by offering thick descriptions of the living realities of this cohort of "mature" mothers, this research challenges the canonical maternal identity and questions its relevance for, and effect on, "mature" mothers' identity constitution. By bringing to light the complex existing realities of these particular mothers, this research critiques the canonical maternal identity by illustrating that each mother's life and her identity constitutions are complex, relationally negotiated and composed and that motherhood is an enduring way of being. Through these illustrations, this research engages with and extends understandings of difference feminism. This research, however, not only rejects, repudiates and contests (Nelson 2001) the narrowly defined canonical maternal identity. By illuminating and articulating the goods which shape and inspire these "mature" mothers' motherwork, this research offers a matricentric account which is consistent with and respectful of the particular, situated realities—the broader familial, social, institutional, but most importantly, moral values and frameworks—in which each mother‘s life is embedded and her motherwork oriented. By understanding and appreciating the complex and multiple webs of relationships in which each mother exists, this matricentric re-stor(y)ing of maternal experiences not only understands and appreciates the unique nature of each mother‘s existing realities, it is oriented to the continuing enhancing of the shared pursuit of the good which underpins particular maternal practices and particular maternal ways of being.

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Software as a Service (SaaS) is a promising approach for Small and Medium Enterprises (SMEs) firms, in particular those that are focused on growing fast and leveraging new technology, due to the potential benefits arising from its inherent scalability, reduced total cost of ownership and the ease of access to global innovations. This paper proposes a dynamic perspective on IS capabilities to understand and explain SMEs sourcing and levering SaaS. The model is derived from combining the IS capabilities of Feeny and Willcocks (1998) and the dynamic capabilities of Teece (2007) and contextualizing it for SMEs and SaaS. We conclude that SMEs sourcing and leveraging SaaS require leadership, business systems thinking and informed buying for sensing and seizing SaaS opportunities and require leadership and vendor development for transforming in terms of aligning and realigning specific tangible and intangible assets.

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It appears that the Industry Commission terms of reference will include a review of (among other things) the appropriateness of the present taxation treatment of charitable organisations. It is uncertain exactly which taxation treatments might be reviewed. However, at a federal government level, a review of the current taxation treatment of charitable organisations could refer to a review of the following taxation measures...

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Adolescent idiopathic scoliosis (AIS) is a complex 3D deformity of the spine, which may require surgical correction in severe cases. Computer models of the spine provide a potentially powerful tool to virtually ‘test’ various surgical scenarios prior to surgery. Using patient-specific computer models of seven AIS patients who had undergone a single rod anterior procedure, we have recently found that the majority of the deformity correction occurs at the apical joint or the joint immediately cephalic to the apex. In the current paper, we investigate the biomechanics of the apical joint for these patients using clinically measured intra-operative compressive forces applied during implant placement. The aim of this study is to determine a relationship between the compressive joint force applied intra-operatively and the achievable deformity correction at the apical joint.

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Outdoor workers are exposed to high levels of ultraviolet radiation (UVR) and may thus be at greater risk to experience UVR-related health effects such as skin cancer, sun burn, and cataracts. A number of intervention trials (n=14) have aimed to improve outdoor workers’ work-related sun protection cognitions and behaviours. Only one study however has reported the use of UV-photography as part of a multi-component intervention. This study was performed in the USA and showed long-term (12 months) improvements in work-related sun protection behaviours. Intervention effects of the other studies have varied greatly, depending on the population studied, intervention applied, and measurement of effect. Previous studies have not assessed whether: - Interventions are similarly effective for workers in stringent and less stringent policy organisations; - Policy effect is translated into workers’ leisure time protection; - Implemented interventions are effective in the long-term; - The facial UV-photograph technique is effective in Australian male outdoor workers without a large additional intervention package, and; - Such interventions will also affect workers’ leisure time sun-related cognitions and behaviours. Therefore, the present Protection of Outdoor Workers from Environmental Radiation [POWER]-study aimed to fill these gaps and had the objectives of: a) assessing outdoor workers’ sun-related cognitions and behaviours at work and during leisure time in stringent and less stringent sun protection policy environments; b) assessing the effect of an appearance-based intervention on workers’ risk perceptions, intentions and behaviours over time; c) assessing whether the intervention was equally effective within the two policy settings; and d) assessing the immediate post-intervention effect. Effectiveness was described in terms of changes in sun-related risk perceptions and intentions (as these factors were shown to be main precursors of behaviour change in many health promotion theories) and behaviour. The study purposefully selected and recruited two organisations with a large outdoor worker contingent in Queensland, Australia within a 40 kilometre radius of Brisbane. The two organisations differed in the stringency of implementation and reinforcement of their organisational sun protection policy. Data were collected from 154 male predominantly Australian born outdoor workers with an average age of 37 years and predominantly medium to fair skin (83%). Sun-related cognitions and behaviours of workers were assessed using self-report questionnaires at baseline and six to twelve months later. Variation in follow-up time was due to a time difference in the recruitment of the two organisations. Participants within each organisation were assigned to an intervention or control group. The intervention group participants received a one-off personalised Skin Cancer Risk Assessment Tool [SCRAT]-letter and a facial UV-photograph with detailed verbal information. This was followed by an immediate post-intervention questionnaire within three months of the start of the study. The control group only received the baseline and follow-up questionnaire. Data were analysed using a variety of techniques including: descriptive analyses, parametric and non-parametric tests, and generalised estimating equations. A 15% proportional difference observed was deemed of clinical significance, with the addition of reported statistical significance (p<0.05) where applicable. Objective 1: Assess and compare the current sun-related risk perceptions, intentions, behaviours, and policy awareness of outdoor workers in stringent and less stringent sun protection policy settings. Workers within the two organisations (stringent n=89 and less stringent n=65) were similar in their knowledge about skin cancer, self efficacy, attitudes, and social norms regarding sun protection at work and during leisure time. Participants were predominantly in favour of sun protection. Results highlighted that compared to workers in a less stringent policy organisation working for an organisation with stringent sun protection policies and practices resulted in more desirable sun protection intentions (less willing to tan p=0.03) ; actual behaviours at work (sufficient use of upper and lower body protection, headgear, and sunglasses (p<0.001 for all comparisons), and greater policy awareness (awareness of repercussions if Personal Protective Equipment (PPE) was not used, p<0.001)). However the effect of the work-related sun protection policy was found not to extend to leisure time sun protection. Objective 2: Compare changes in sun-related risk perceptions, intentions, and behaviours between the intervention and control group. The effect of the intervention was minimal and mainly resulted in a clinically significant reduction in work-related self-perceived risk of developing skin cancer in the intervention compared to the control group (16% and 32% for intervention and control group, respectively estimated their risk higher compared to other outdoor workers: , p=0.11). No other clinical significant effects were observed at 12 months follow-up. Objective 3: Assess whether the intervention was equally effective in the stringent sun protection policy organisation and the less stringent sun protection policy organisation. The appearance-based intervention resulted in a clinically significant improvement in the stringent policy intervention group participants’ intention to protect from the sun at work (workplace*time interaction, p=0.01). In addition to a reduction in their willingness to tan both at work (will tan at baseline: 17% and 61%, p=0.06, at follow-up: 54% and 33%, p=0.07, stringent and less stringent policy intervention group respectively. The workplace*time interaction was significant p<0.001) and during leisure time (will tan at baseline: 42% and 78%, p=0.01, at follow-up: 50% and 63%, p=0.43, stringent and less stringent policy intervention group respectively. The workplace*time interaction was significant p=0.01) over the course of the study compared to the less stringent policy intervention group. However, no changes in actual sun protection behaviours were found. Objective 4: Examine the effect of the intervention on level of alarm and concern regarding the health of the skin as well as sun protection behaviours in both organisations. The immediate post-intervention results showed that the stringent policy organisation participants indicated to be less alarmed (p=0.04) and concerned (p<0.01) about the health of their skin and less likely to show the facial UV-photograph to others (family p=0.03) compared to the less stringent policy participants. A clinically significantly larger proportion of participants from the stringent policy organisation reported they worried more about skin cancer (65%) and skin freckling (43%) compared to those in the less stringent policy organisation (46%,and 23% respectively , after seeing the UV-photograph). In summary the results of this study suggest that the having a stringent work-related sun protection policy was significantly related to for work-time sun protection practices, but did not extend to leisure time sun protection. This could reflect the insufficient level of sun protection found in the general Australian population during leisure time. Alternatively, reactance caused by being restricted in personal decisions through work-time policy could have contributed to lower leisure time sun protection. Finally, other factors could have also contributed to the less than optimal leisure time sun protection behaviours reported, such as unmeasured personal or cultural barriers. All these factors combined may have lead to reduced willingness to take proper preventive action during leisure time exposure. The intervention did not result in any measurable difference between the intervention and control groups in sun protection behaviours in this population, potentially due to the long lag time between the implementation of the intervention and assessment at 12-months follow-up. In addition, high levels of sun protection behaviours were found at baseline (ceiling effect) which left little room for improvement. Further, this study did not assess sunscreen use, which was the predominant behaviour assessed in previous effective appearance-based interventions trials. Additionally, previous trials were mainly conducted in female populations, whilst the POWER-study’s population was all male. The observed immediate post-intervention result could be due to more emphasis being placed on sun protection and risks related to sun exposure in the stringent policy organisation. Therefore participants from the stringent policy organisation could have been more aware of harmful effects of UVR and hence, by knowing that they usually protect adequately, not be as alarmed or concerned as the participants from the less stringent policy organisation. In conclusion, a facial UV-photograph and SCRAT-letter information alone may not achieve large changes in sun-related cognitions and behaviour, especially of assessed 6-12 months after the intervention was implemented and in workers who are already quite well protected. Differences found between workers in the present study appear to be more attributable to organisational policy. However, against a background of organisational policy, this intervention may be a useful addition to sun-related workplace health and safety programs. The study findings have been interpreted while respecting a number of limitations. These have included non-random allocation of participants due to pre-organised allocation of participants to study group in one organisation and difficulty in separating participants from either study group. Due to the transient nature of the outdoor worker population, only 105 of 154 workers available at baseline could be reached for follow-up. (attrition rate=32%). In addition the discrepancy in the time to follow-up assessment between the two organisations was a limitation of the current study. Given the caveats of this research, the following recommendations were made for future research: - Consensus should be reached to define "outdoor worker" in terms of time spent outside at work as well as in the way sun protection behaviours are measured and reported. - Future studies should implement and assess the value of the facial UV-photographs in a wide range of outdoor worker organisations and countries. - More timely and frequent follow-up assessments should be implemented in intervention studies to determine the intervention effect and to identify the best timing of booster sessions to optimise results. - Future research should continue to aim to target outdoor workers’ leisure time cognitions and behaviours and improve these if possible. Overall, policy appears to be an important factor in workers’ compliance with work-time use of sun protection. Given the evidence generated by this research, organisations employing outdoor workers should consider stringent implementation and reinforcement of a sun protection policy. Finally, more research is needed to improve ways to generate desirable behaviour in this population during leisure time.

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The prevalence of International New Ventures (INVs) has increased during the past twenty years. Nevertheless, to date there has been no general consensus within the literature on an explanation as to the rapid internationalisation of some firms. Do they follow a similar process to other firms that internationalise based on a more ‘measured’ incremental sequential process of internationalisation. This paper proposes and tests an innovation diffusion model of the internationalisation of small firm INVs and others by drawing on key innovation diffusion models from the literature. The results of this analysis indicate that the synthesised model of export adoption is effective in explaining the internationalisation process of INVs and other firms within the Queensland Food and Beverage Industry. Significantly, the features of the original innovation diffusion models developed in the consumer behaviour literature, which had limited examination within the internationalisation literature, were confirmed. This includes the ability of firms, or specifically decision-makers, to skip stages based on previous experience.

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Introduction and objectives Early recognition of deteriorating patients results in better patient outcomes. Modified early warning scores (MEWS) attempt to identify deteriorating patients early so timely interventions can occur thus reducing serious adverse events. We compared frequencies of vital sign recording 24 h post-ICU discharge and 24 h preceding unplanned ICU admission before and after a new observation chart using MEWS and an associated educational programme was implemented into an Australian Tertiary referral hospital in Brisbane. Design Prospective before-and-after intervention study, using a convenience sample of ICU patients who have been discharged to the hospital wards, and in patients with an unplanned ICU admission, during November 2009 (before implementation; n = 69) and February 2010 (after implementation; n = 70). Main outcome measures Any change in a full set or individual vital sign frequency before-and-after the new MEWS observation chart and associated education programme was implemented. A full set of vital signs included Blood pressure (BP), heart rate (HR), temperature (T°), oxygen saturation (SaO2) respiratory rate (RR) and urine output (UO). Results After the MEWS observation chart implementation, we identified a statistically significant increase (210%) in overall frequency of full vital sign set documentation during the first 24 h post-ICU discharge (95% CI 148, 288%, p value <0.001). Frequency of all individual vital sign recordings increased after the MEWS observation chart was implemented. In particular, T° recordings increased by 26% (95% CI 8, 46%, p value = 0.003). An increased frequency of full vital sign set recordings for unplanned ICU admissions were found (44%, 95% CI 2, 102%, p value = 0.035). The only statistically significant improvement in individual vital sign recordings was urine output, demonstrating a 27% increase (95% CI 3, 57%, p value = 0.029). Conclusions The implementation of a new MEWS observation chart plus a supporting educational programme was associated with statistically significant increases in frequency of combined and individual vital sign set recordings during the first 24 h post-ICU discharge. There were no significant changes to frequency of individual vital sign recordings in unplanned admissions to ICU after the MEWS observation chart was implemented, except for urine output. Overall increases in the frequency of full vital sign sets were seen.

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Objectives This prospective study investigated the effects of caffeine ingestion on the extent of adenosine-induced perfusion abnormalities during myocardial perfusion imaging (MPI). Methods Thirty patients with inducible perfusion abnormalities on standard (caffeine-abstinent) adenosine MPI underwent repeat testing with supplementary coffee intake. Baseline and test MPIs were assessed for stress percent defect, rest percent defect, and percent defect reversibility. Plasma levels of caffeine and metabolites were assessed on both occasions and correlated with MPI findings. Results Despite significant increases in caffeine [mean difference 3,106 μg/L (95% CI 2,460 to 3,752 μg/L; P < .001)] and metabolite concentrations over a wide range, there was no statistically significant change in stress percent defect and percent defect reversibility between the baseline and test scans. The increase in caffeine concentration between the baseline and the test phases did not affect percent defect reversibility (average change −0.003 for every 100 μg/L increase; 95% CI −0.17 to 0.16; P = .97). Conclusion There was no significant relationship between the extent of adenosine-induced coronary flow heterogeneity and the serum concentration of caffeine or its principal metabolites. Hence, the stringent requirements for prolonged abstinence from caffeine before adenosine MPI—based on limited studies—appear ill-founded.

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The purpose of this study was to investigate the effect of very small air gaps (less than 1 mm) on the dosimetry of small photon fields used for stereotactic treatments. Measurements were performed with optically stimulated luminescent dosimeters (OSLDs) for 6 MV photons on a Varian 21iX linear accelerator with a Brainlab μMLC attachment for square field sizes down to 6 mm × 6 mm. Monte Carlo simulations were performed using EGSnrc C++ user code cavity. It was found that the Monte Carlo model used in this study accurately simulated the OSLD measurements on the linear accelerator. For the 6 mm field size, the 0.5 mm air gap upstream to the active area of the OSLD caused a 5.3 % dose reduction relative to a Monte Carlo simulation with no air gap. A hypothetical 0.2 mm air gap caused a dose reduction > 2 %, emphasizing the fact that even the tiniest air gaps can cause a large reduction in measured dose. The negligible effect on an 18 mm field size illustrated that the electronic disequilibrium caused by such small air gaps only affects the dosimetry of the very small fields. When performing small field dosimetry, care must be taken to avoid any air gaps, as can be often present when inserting detectors into solid phantoms. It is recommended that very small field dosimetry is performed in liquid water. When using small photon fields, sub-millimetre air gaps can also affect patient dosimetry if they cannot be spatially resolved on a CT scan. However the effect on the patient is debatable as the dose reduction caused by a 1 mm air gap, starting out at 19% in the first 0.1 mm behind the air gap, decreases to < 5 % after just 2 mm, and electronic equilibrium is fully re-established after just 5 mm.

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We hypothesised that a potentially disease-modifying osteoarthritis (OA) drug such as hyaluronic acid (HA) given in combination with anti-inflammatory signalling agents such as mitogen-activated protein kinase kinase–extracellular signal-regulated kinase (MEK-ERK) signalling inhibitor (U0126) could result in additive or synergistic effects on preventing the degeneration of articular cartilage. Chondrocyte differentiation and hypertrophy were evaluated using human OA primary cells treated with either HA or U0126, or the combination of HA + U0126. Cartilage degeneration in menisectomy (MSX) induced rat OA model was investigated by intra-articular delivery of either HA or U0126, or the combination of HA + U0126. Histology, immunostaining, RT-qPCR, Western blotting and zymography were performed to assess the expression of cartilage matrix proteins and hypertrophic markers. Phosphorylated ERK (pERK)1/2-positive chondrocytes were significantly higher in OA samples compared with those in healthy control suggesting the pathological role of that pathway in OA. It was noted that HA + U0126 significantly reduced the levels of pERK, chondrocyte hypertrophic markers (COL10 and RUNX2) and degenerative markers (ADAMTs5 and MMP-13), however, increased the levels of chondrogenic markers (COL2) compared to untreated or the application of HA or U0126 alone. In agreement with the results in vitro, intra-articular delivery of HA + U0126 showed significant therapeutic improvement of cartilage in rat MSX OA model compared with untreated or the application of HA or U0126 alone. Our study suggests that the combination of HA and MEK-ERK inhibition has a synergistic effect on preventing cartilage degeneration.

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Twitter has developed an increasingly visible presence in Australian journalism, and in the discussion of news. Many journalists have begun to explore manageable approaches to incorporating Twitter into their work practices, and for some – like the ABC’s ‘star recruits’ Annabel Crabb and Latika Bourke – it has already become a career driver. This article examines the positioning of journalists as ‘personal brands’ on Twitter, by documenting the visibility of leading personal and institutional accounts during two major political events in Australia: the Rudd/Gillard leadership spill on 23 June 2010, and the day of the subsequent federal election on 21 August 2010. It highlights the fact that in third-party networks such as Twitter, journalists and news organisations no longer operate solely on their own terms, as they do on their own Websites, but gain and maintain prominence in the network and reach for their messages only in concert with other users. It places these observations in a wider context of journalist/audience relations, a decade after the emergence of the first citizen journalism Websites.

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Background Previous studies have found that high and cold temperatures increase the risk of childhood diarrhea. However, little is known about whether the within-day variation of temperature has any effect on childhood diarrhea. Methods A Poisson generalized linear regression model combined with a distributed lag non-linear model was used to examine the relationship between diurnal temperature range and emergency department admissions for diarrhea among children under five years in Brisbane, from 1st January 2003 to 31st December 2009. Results There was a statistically significant relationship between diurnal temperature range and childhood diarrhea. The effect of diurnal temperature range on childhood diarrhea was the greatest at one day lag, with a 3% (95% confidence interval: 2%–5%) increase of emergency department admissions per 1°C increment of diurnal temperature range. Conclusion Within-day variation of temperature appeared to be a risk factor for childhood diarrhea. The incidence of childhood diarrhea may increase if climate variability increases as predicted.

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We investigated the effect of hydrotherapy on time-trial performance and cardiac parasympathetic reactivation during recovery from intense training. On three occasions, 18 well-trained cyclists completed 60 min high-intensity cycling, followed 20 min later by one of three 10-min recovery interventions: passive rest (PAS), cold water immersion (CWI), or contrast water immersion (CWT). The cyclists then rested quietly for 160 min with R-R intervals and perceptions of recovery recorded every 30 min. Cardiac parasympathetic activity was evaluated using the natural logarithm of the square root of mean squared differences of successive R-R intervals (ln rMSSD). Finally, the cyclists completed a work-based cycling time trial. Effects were examined using magnitude-based inferences. Differences in time-trial performance between the three trials were trivial. Compared with PAS, general fatigue was very likely lower for CWI (difference [90% confidence limits; -12% (-18; -5)]) and CWT [-11% (-19; -2)]. Leg soreness was almost certainly lower following CWI [-22% (-30; -14)] and CWT [-27% (-37; -15)]. The change in mean ln rMSSD following the recovery interventions (ln rMSSD(Post-interv)) was almost certainly higher following CWI [16.0% (10.4; 23.2)] and very likely higher following CWT [12.5% (5.5; 20.0)] compared with PAS, and possibly higher following CWI [3.7% (-0.9; 8.4)] compared with CWT. The correlations between performance, ln rMSSD(Post-interv) and perceptions of recovery were unclear. A moderate correlation was observed between ln rMSSD(Post-interv) and leg soreness [r = -0.50 (-0.66; -0.29)]. Although the effects of CWI and CWT on performance were trivial, the beneficial effects on perceptions of recovery support the use of these recovery strategies.

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Situation awareness lost is a common factor leading to human error in the aviation industry. However, few studies have investigated the effect on situation awareness where the control interface is a touch-screen device that supports simultaneous multi-touch input and information output. This research aims to conduct an experiment to evaluate the difference in situation awareness on a large screen device, DiamondTouch (DT107), and a small screen device, iPad, both with multi-touch interactive functions. The Interface Operation and Situation Awareness Testing Simulator (IOSATS), is a simulator to test the three basis interface operations (Search Target, Information Reading, and Change Detection) by implementing a simplified search and rescue scenario. The result of this experiment will provide reliable data for future research for improving operator's situation awareness in the avionic domain.