Role of lithium vacancies in accelerating the dehydrogenation kinetics on a LiBH4(010) surface : an Ab initio study

In this work, ab initio density functional calculations were performed to explore the effect of surface lithium vacancies on the initial dehydrogenation kinetics of lithium borohydride. We found that some B−H bonds in neighboring BH4-1 complexes around the vacancy became elongated (weakened). The activation barriers for the recombination of H atoms to form H2 were decreased from 3.64 eV for the stoichiometrically complete LiBH4(010) surface to 1.53 and 0.23 eV in the presence of mono- and di-vacancies, respectively. Our results indicate that the creation of Li vacancies may play a critical role in accelerating the dehydrogenation kinetics of LiBH4.

The role of perceived usefulness and attitude on electronic health record acceptance : an empirical investigation using response surface analysis

Information and communications technologies are a significant component of the healthcare domain and electronic health records play a major role within it. As a result, it is important that they are accepted en masse by healthcare professionals. How healthcare professionals perceive the usefulness of electronic health records and their attitudes towards them have been shown to have significant effects on their overall acceptance. This paper investigates the role of perceived usefulness and attitude on the intention to use electronic health records by future healthcare professionals using polynomial regression with response surface analysis. Results show that the relationship is more complex than predicted in prior research. The paper concludes that the predicting properties of the above determinants must be further investigated to clearly understand their role in predicting the intention to use electronic health records and in designing systems that are better adopted by healthcare professionals of the future.

Still valuing play

Play has had a prominent position in early childhood education and care (ECEC) for over 200 years. As educators, we tend to talk about young children learning through play as a matter of fact. In our first national Early Years Learning Framework (Department of Education, Employment and Workplace Relations, 2009), play is promoted as the right of all children, an integral part of being a child and as the prime context for learning in the early years. While the Early Years Learning Framework (EYLF) defines its use of the term ‘play’, there are differing perspectives on what constitutes play, the relationship between play and learning,and the educator’s role in play. In this context, it might be interesting to go a little deeper, and to look at some different perspectives on play and learning.

A possible role for mitochondrial dysfunction in migraine

Migraine is a common neurological disorder characterised by debilitating head pain and an assortment of additional symptoms which can include nausea, emesis, photophobia, phonophobia and occasionally visual sensory disturbances. Migraine is a complex disease caused by an interplay between predisposing genetic variants and environmental factors. It affects approximately 12 % of studied Caucasian populations with affected individuals being predominantly female. Genes involved in neurological, vascular or hormonal pathways have all been implicated in predisposition towards developing migraine. All of these are nuclear encoded genes, but given the role of mitochondria in a number of neurological disorders and in energy production it is possible that mitochondrial variants may play a role in the pathogenesis of this disease. Mitochondrial DNA has been a useful tool for studying population genetics and human genetic diseases due to the clear inheritance shown through successive generations. Given the clear gender bias found in migraine patients it may be important to investigate X-linked inheritance and mitochondrial-related variants in this disorder. This paper explores the possibility that mitochondrial DNA changes may play a role in migraine. Few variants in the mitochondrial genome have so far been investigated in migraine and new studies should be aimed towards investigating the role of mitochondrial DNA in this common disorder.

International acclaim : the role(s) of the international film festival in supporting emerging women’s cinema

International Film Festivals act as important sites for the exhibition of contemporary world cinema. Film festivals represent an increasingly transnational film culture, where audiences, filmmakers, distributors, press, critics and academics come together from all over the world to discover new films, network with one another and debate about the past, present and future of cinema. This research project investigates the role that international film festivals play within the wider international film industry, with a specific focus on emerging women filmmakers. It therefore explores the arena of contemporary women.s cinema at its intersection with the international film festival industry. The significance and original contribution of the research is its intervention in the growing field of film festival studies through a specific investigation of how international film festivals support emerging women filmmakers. The positioning of the research at the intersection of feminist film theory and festival research within the broader context of transnational cinema allows the examination of each festival, the attending filmmakers and their films to be addressed within a more refined and nuanced lens. A core method for the thesis is the close textual analysis of particular emerging women filmmakers. films which are screened at the respective festivals. The research also utilises the qualitative research strategies of the case study and the interview to ¡°seek to understand the context or setting of the participants through visiting this context and gathering information personally¡± (Creswell 2003, 9). The textual analysis is used in dialogue with the interviews and the participant observational data gathering to provide a related context for understanding these films and their cultural meanings, both personally for the filmmaker and transnationally across the festival circuit. The focus of the case studies is the Brisbane International Film Festival, the International Film Festival Rotterdam and the Toronto International Film Festival. These three festivals were chosen for their distinct geographical locations in the Asia Pacific, Europe and North America, as well as for their varying size and influence on the international film festival circuit. Specifically, I investigate the reasons behind why the organisers of a particular festival have chosen a certain woman.s film, how it is then packaged or displayed within the programme, and how all of this impacts on the filmmaker herself. The focus of my research is to investigate film festivals and their .real-life. applications and benefits for the filmmakers being supported, both through the exhibition of their films and through their attendance as festival guests. The research finds that the current generation of emerging women filmmakers has varying levels of experience and success at negotiating the international film festival circuit. Each of the three festivals examined include and promote the films of emerging women filmmakers through a range of strategies, such as specific programming strands dedicated to showcasing emerging talent, financial support through festival funds, providing visibility within the programme, exposure to international audiences and networking opportunities with industry professionals and other filmmakers. Furthermore, the films produced by the emerging women filmmakers revealed a strong focus on women.s perspectives and experiences, which were explored through the interweaving of particular aesthetic and cinematographic conventions.

The role of immunoglobulins and their transporters in urogenital Chlamydial infections

Chlamydia trachomatis infections of the male and female reproductive tracts are the world's leading sexually transmitted bacterial disease, and can lead to damaging pathology, scarring and infertility. The resolution of chlamydial infection requires the development of adaptive immune responses to infection, and includes cell-mediated and humoral immunity. Whilst cluster of differentiation (CD)4+ T cells are known to be essential in clearance of infection [1], they are also associated with immune cell infiltration, autoimmunity and infertility in the testes [2-3]. Conversely, antibodies are less associated with inflammation, are readily transported into the reproductive tracts, and can offer lumenal neutralization of chlamydiae prior to infection. Antibodies, or immunoglobulins (Ig), play a supportive role in the resolution of chlamydial infections, and this thesis sought to define the function of IgA and IgG, against a variety of chlamydial antigens expressed during the intracellular and extracellular stages of the chlamydial developmental cycle. Transport of IgA and IgG into the mucosal lumen is facilitated by receptor-mediated transcytosis yet the expression profile (under normal conditions and during urogenital chlamydial infection) of the polymeric immunoglobulin receptor (pIgR) and the neonatal Fc receptor (FcRn) remains unknown. The expression profile of pIgR and FcRn in the murine male reproductive tract was found to be polarized to the lower and upper reproductive tract tissues respectively. This demonstrates that the two receptors have a tissue tropism, which must be considered when targeting pathogens that colonize different sites. In contrast, the expression of pIgR and FcRn in the female mouse was found to be distributed in both the upper and lower reproductive tracts. When urogenitally infected with Chlamydia muridarum, both male and female reproductive tracts up-regulated expression of pIgR and down-regulated expression of FcRn. Unsurprisingly, the up-regulation of pIgR increased the concentration of IgA in the lumen. However, down-regulation of FcRn, prevented IgG uptake and led to an increase or pooling of IgG in lumenal secretions. As previous studies have identified the importance of pIgR-mediated delivery of IgA, as well as the potential of IgA to bind and neutralize intracellular pathogens, IgA against a variety of chlamydial antigens was investigated. The protection afforded by IgA against the extracellular antigen major outer membrane protein (MOMP), was found to be dependent on pIgR expression in vitro and in vivo. It was also found that in the absence of pIgR, no protection was afforded to mice previously immunized with MOMP. The protection afforded from polyclonal IgA against the intracellular chlamydial antigens; inclusion membrane protein A (IncA), inclusion membrane proteins (IncMem) and secreted chlamydial protease-like activity factor (CPAF) were produced and investigated in vitro. Antigen-specific intracellular IgA was found to bind to the respective antigen within the infected cell, but did not significantly reduce inclusion formation (p > 0.05). This suggests that whilst IgA specific for the selected antigens was transported by pIgR to the chlamydial inclusion, it was unable to prevent growth. Similarly, immunization of male mice with intracellular chlamydial antigens (IncA or IncMem), followed by depletion CD4+ T cells, and subsequent urogenital C. muridarum challenge, provided minimal pIgR-mediated protection. Wild type male mice immunized with IncA showed a 57 % reduction (p < 0.05), and mice deficient in pIgR showed a 35 % reduction (p < 0.05) in reproductive tract chlamydial burden compared to control antigen, and in the absence of CD4+ T cells. This suggests that pIgR and secretory IgA (SIgA) were playing a protective role (21 % pIgR-mediated) in unison with another antigen-specific immune mechanism (36 %). Interestingly, IgA generated during a primary respiratory C. muridarum infection did not provide a significant amount of protection to secondary urogenital C. muridarum challenge. Together, these data suggest that IgA specific for an extracellular antigen (MOMP) can play a strong protective role in chlamydial infections, and that IgA targeting intracellular antigens is also effective but dependent on pIgR expression in tissues. However, whilst not investigated here, IgA targeting and blocking other intracellular chlamydial antigens, that are more essential for replication or type III secretion, may be more efficacious in subunit vaccines. Recently, studies have demonstrated that IgG can neutralize influenza virus by trafficking IgG-bound virus to lysosomes [4]. We sought to determine if this process could also traffic chlamydial antigens for degradation by lysosomes, despite Chlamydia spp. actively inhibiting fusion with the host endocytic pathway. As observed in pIgR-mediated delivery of anti-IncA IgA, FcRn similarly transported IgG specific for IncA which bound the inclusion membrane. Interestingly, FcRn-mediated delivery of anti-IncA IgG significantly decreased inclusion formation by 36 % (p < 0.01), and induced aberrant inclusion morphology. This suggests that unlike IgA, IgG can facilitate additional host cellular responses which affect the intracellular niche of chlamydial growth. Fluorescence microscopy revealed that IgG also bound the inclusion, but unlike influenza studies, did not induce the recruitment of lysosomes. Notably, anti-IncA IgG recruited sequestosomes to the inclusion membrane, markers of the ubiquitin/proteasome pathway and major histocompatibility complex (MHC) class I loading. To determine if the protection against C. muridarum infection afforded by IncA IgG in vitro translated in vivo, wild type mice and mice deficient in functional FcRn and MHC-I, were immunized, depleted of CD4+, and urogenitally infected with C. muridarum. Unlike in pIgR-deficient mice, the protection afforded from IncA immunization was completely abrogated in mice lacking functional FcRn and MHC-I/CD8+. Thus, both anti-IncA IgA and IgG can bind the inclusion in a pIgR and FcRn-mediated manner, respectively. However, only IgG mediates a higher reduction in chlamydial infection in vitro and in vivo suggesting more than steric blocking of IncA had occurred. Unlike anti-MOMP IgA, which reduced chlamydial infection of epithelial cells and male mouse tissues, IgG was found to enhance infectivity in vitro, and in vivo. Opsonization of EBs with MOMP-IgG enhanced inclusion formation of epithelial cells in a MOMP-IgG dose-dependent and FcRn-dependent manner. When MOMP-IgG opsonized EBs were inoculated into the vagina of female mice, a small but non-significant (p > 0.05) enhancement of cervicovaginal C. muridarum shedding was observed three days post infection in mice with functional FcRn. Interestingly, infection with opsonized EBs reduced the intensity of the peak of infection (day six) but protracted the duration of infection by 60 % in wild type mice only. Infection with EBs opsonized in IgG also significantly increased (p < 0.05) hydrosalpinx formation in the oviducts and induced lymphocyte infiltration uterine horns. As MOMP is an immunodominant antigen, and is widely used in vaccines, the ability of IgG specific to extracellular chlamydial antigens to enhance infection and induce pathology needs to be considered. Together, these data suggest that immunoglobulins play a dichotomous role in chlamydial infections, and are dependent on antigen specificity, FcRn and pIgR expression. FcRn was found to be highly expressed in upper male reproductive tract, whilst pIgR was dominantly expressed in the lower reproductive tract. Conversely, female mice expressed FcRn and pIgR in both the lower and upper reproductive tracts. In response to a normal chlamydial infection, pIgR is up-regulated increasing secretory IgA release, but FcRn is down-regulated preventing IgG uptake. Similarly to other studies [5-6], we demonstrate that IgA and IgG generated during primary chlamydial infections plays a minor role in recall immunity, and that antigen-specific subunit vaccines can offer more protection. We also show that both IgA and IgG can be used to target intracellular chlamydial antigens, but that IgG is more effective. Finally, IgA against the extracellular antigen MOMP can afford protection, whist IgG plays a deleterious role by increasing infectivity and inducing damaging immunopathology. Further investigations with additional antigens or combination subunit vaccines will enhance our understanding the protection afforded by antibodies against intracellular and extracellular pathogenic antigens, and help improve the development of an efficacious chlamydial vaccine.

The interface of acute and aged care : the role of the nurse in a provincial area

Objective This study was to investigate issues that arose from pre-admission to post-discharge, for people in Toowoomba, Queensland over the age of 65 admitted to an acute facility. This paper concentrates on a significant concern that emerged from the large amount of data collected during this project, that is,the role of the nurse in the continuum of health care involving elderly people. Method The study involved a multi-site, multi-agency and multi-method (qualitative and quantitative) approach. Data was collected from regional service providers, the Department of Health and Aged Care (DHAC), the Australian Bureau of Statistics (ABS), Home and Community Care (HACC), the Aged Care Assessment Team (ACAT), elderly people who had been discharged from regional hospitals and their carers, residents of regional aged care facilities, area health professionals and elderly regional hospital inpatients. Results The data indicated that nurses in this provincial area currently play a limited role in preadmission planning, being mostly concerned with elective surgery, especially joint replacements. While nurses deliver the majority of care during hospitalisation, they do not appear to be cognizant of the needs of the elderly regarding post-acute discharge. Conclusion The recent introduction of the model of nurse case management in the acute sector appears to be a positive development that will streamline and optimise the health care of the elderly across the continuum in the Toowoomba area. The paper recommends some strategies, such as discharge liaison nurses based in Emergency Departments and the expansion of the nurse case management role, which would optimise care for the elderly person at the interface of care.

Exploring the role of activity in genre

This paper provides an outline of genre as we currently know it, and examines the changes occurring as games become more complex. Recent research we've undertaken suggests that our perception of which games fall into which genre category is subjective and that genre hybridization continues to blur our understanding of these categories. Consequently, it is becoming increasingly difficult to categorise game play experience based on traditional genre classifications. We examine the use of videogame activities as a useful mechanism for supplementing our understanding of videogame genre. Through considering activity as a means of classifying game experiences we may obtain a much more nuanced understanding of how players engage with games within a particular genre and across genres.

Potential role of bcl-2 as a suppressor of tumour angiogenesis in non- small-cell lung cancer

It has been reported that genes regulating apoptosis may play a role in tumoral angiogenesis. This study examined the relationship between tumour vascularization, a measure of tumour angiogenesis, and bcl-2 and p53 expression in operable non-small-cell lung cancer (NSCLC). The relationship between bcl-2, p53 and tumour vascularization and epidermal-growth-factor- receptor(EGFR) and c-erbB-2 expression was also studied. Tissue sections from resected tumour specimens of 107 NSCLC patients were evaluated immunohistochemically for vascular grade and bcl-2, p53, EGFR and c-erbB-2 expression. bcl-2 expression was found in 20/107 (19%) cases and was associated with squamous-cell histology (p = 0.03). A strong inverse relationship was found between bcl-2 expression and vascular grade (p = 0.005). All c-erbB-2-positive cases were negative for bcl-2 expression (p = 0.01). Overall no association was found between c-erbB-2 expression and vascular grade. However, in bcl-2-negative cases positive c-erbB-2 expression correlated with low angiogenesis (p = 0.05). No relationship was found between p53 and EGFR expression and bcl-2, c-erbB-2 or vascular grade. The improved prognosis reported in bcl-2-positive NSCLC may be related to low tumour vascularization. The results suggest that the anti-apoptotic gene bcl- 2 plays a role in regulating tumour angiogenesis. Since normal lung epithelium expresses bcl-2, a sequence of tumour progression involving loss of bcl-2, then activation of c-erbB-2 or increase in tumour vascularization is proposed.

Role of Human Topoisomerase I in DNA Repair and Apoptosis

Human topoisomerase I (htopoI) is an enzyme that up to now was believed to function mainly in the removal of torsional stress generated during transcription and replication. In 1998, it was found that htopoI might play another important role in the cellular response to DNA damage -- the so-called htopoI damage response. Since this initial discovery, many studies have suggested that the htopoI damage response is involved in DNA repair as well as in apoptosis. Here we discuss the earliest as well as the latest results in this field. Combining all of the published and as yet unpublished results, we suggest and discuss a model of how htopoI may function during DNA repair and apoptosis. Furthermore, numerous results show that the htopoI damage response is not a spontaneous event, but is strictly regulated by cellular signalling pathways. We discuss which pathways may be involved and how the htopoI damage response is activated. Although the htopoI damage response was discovered several years ago, research in this area is just beginning. The future will surely bring more clarity regarding the precise mechanism behind the involvement of htopoI in DNA repair and apoptosis, as well as its implications for a broader understanding of how the human organism ensures genomic stability.

The human topoisomerase I damage response plays a role in apoptosis

Previous studies have shown that human topoisomerase I cleavage complexes form as a response to various DNA damages in vivo, the so called human topoisomerase I “damage response”. It was suggested that this damage response may play a role in DNA repair as well as in apoptosis, but only very few investigations have been done and the significance of the damage response still remains unclear. Here we demonstrate that human topoisomerase I cleavage complexes induced by high doses of UV irradiation are highly stable for up to 48 h. Furthermore, we show that human topoisomerase I cleavage complexes correlate with apoptosis. However, at low UV doses the cleavage complex level was very low and the complexes were repaired. Surprisingly, we found that high levels of stable cleavage complexes were not only found in UV-irradiated cells but also in untreated cells that underwent apoptosis. A possible role of human topoisomerase I in apoptosis is discussed.

The role of the glucocorticoids in developing resilience to stress and addiction

There is emerging evidence that individuals have the capacity to learn to be resilient by developing protective mechanisms that prevent them from the maladaptive effects of stress that can contribute to addiction.The emerging field of the neuroscience of resilience is beginning to uncover the circuits and molecules that protect against stress-related neuropsychiatric diseases, such as addiction. Glucocorticoids (GCs) are important regulators of basal and stress-related homeostasis in all higher organisms and influence a wide array of genes in almost every organ and tissue. GCs, therefore, are ideally situated to either promote or prevent adaptation to stress. In this review, we will focus on the role of GCs in the hypothalamic-pituitary adrenocortical axis and extra-hypothalamic regions in regulating basal and chronic stress responses. GCs interact with a large number of neurotransmitter and neuropeptide systems that are associated with the development of addiction. Additionally, the review will focus on the orexinergic and cholinergic pathways and highlight their role in stress and addiction. GCs play a key role in promoting the development of resilience or susceptibility and represent important pharmacotherapeutic targets that can reduce the impact of a maladapted stress system for the treatment of stress-induced addiction.

The role of common but differentiated responsibility in the 2020 climate regime

The principle of common but differentiated responsibility (CBDR) will play a role in the 2020 Climate Regime. This Article starts by examining differential treatment within the international legal order, finding that it is ethically and practically difficult to implement an international climate instrument based on formal equality. There is evidence of state parties accepting differential responsibilities in a number of areas within the international legal order and the embedding of CBDR in the United Nations Framework Convention on Climate Change (UNFCCC), means that that differential commitments will lie at the heart of the 2020 climate regime. The UNFCCC applies the implementation method of differentiation, while the Kyoto Protocol applies both the obligation and implementation method of differentiation. It is suggested that the implementation model will be the differentiation model retained in the 2020 climate agreement. The Parties’ submissions under the Durban Platform are considered in order to gain an understanding of their positions on CBDR. While there are areas of contention including the role of principles in shaping obligations and the ongoing legal status of Annex I and Non-Annex I distinction, there is broad consensus among the parties in favour of differentiation by implementation with developed and major economies undertaking Quantified Emission Limitation and Reduction Objectives (economy wide targets) and developing countries that are not major economies undertaking sectoral targets.

Teachers and academics researching together : children's views on play

An international early years project led by QUT and University of Iceland researchers has investigated children’s accounts of play and the teacher’s role in play in kindergarten settings. While most commonly associated with young children’s activities and the work of childhood, play is recognised also as an activity that extends over the life span, from early childhood to adulthood, and across cultures, worldwide. As shown in national and state policy and curriculum documents, play is being subjected increasingly to specific guidelines that address the physical environment and educator involvement in early years settings. Parents and educators have strong opinions regarding the value and place of play. Children also have strong views about play, although little is known about their views and what they think play encompasses, and the value of play in their everyday lives.

Experiential role of artefacts in cooperative design

The role of material artefacts in supporting distributed and co-located work practices has been well acknowledged within HCI and CSCW research. In this paper, we show that in addition to their ecological, coordinative and organizational support, artefacts also play an 'experiential' role. In this case, artefacts not only improve efficiency or have a purely functional role (e.g. allowing people to complete tasks quickly), but the materiality, use and manifestations of these artefacts bring quality and richness to people's performance and help them make better sense of their everyday lives. In a domain such as industrial design, such artefacts play an important role for supporting creativity and innovation. Based on our ethnographic fieldwork on understanding cooperative design practices of industrial design students and researchers, we describe several experiential practices that are supported by design-related artefacts such as sketches, drawings, physical models and explorative prototypes -- used and developed in designers' everyday work. Our main intention in carrying out this kind of research is to develop technologies to support designers' everyday practices. We believe that with the emergence of ubiquitous computing, there is a growing need to focus on the personal, social and creative side of people's everyday experiences. By focusing on the experiential practices of designers, we can provide a much broader view in the design of new interactive technologies.