Kinetics of electron recombination of dye-senitized solar cells based on TiO2 nanorod arrays sensitized with different dyes

The performance and electron recombination kinetics of dye-sensitized solar cells based on TiO2 films consisting of one-dimensional nanorod arrays (NR-DSSCs) which are sensitized with dye N719, C218 and D205 respectively have been studied. It has been found that the best efficiency is obtained with the dye C218 based NR-DSSCs, benefiting from a 40% higher short-circuit photocurrent density. However, the open circuit photovoltage of the N719 based cell is 40 mV higher than that of the organic dye C218 and D205 based devices. Investigation of the electron recombination kinetics of the NR-DSSCs has revealed that the effective electron lifetime, τn, of the N719 based NR-DSSC is the lowest whereas the τn of the C218 based NR-DSSC is the highest among the three dyes. The higher Voc with the N719 based NR-DSSC is originated from the more negative energy level of the conduction band of the TiO2 film. In addition, in comparison to the DSSCs with conventional nanocrystalline particles based TiO2 films, the NR-DSSCs have shown over two orders of magnitude higher τn when employing N719 as the sensitizer. Nevertheless, the τn of the DSSCs with the C218 based nanorod arrays is only ten-fold higher than the that of the nanoparticles based devices. The remarkable characteristic of the dye C218 in suppressing the electron recombination of DSSCs is discussed.

The effect of various temperature indicators on different mortality categories in a subtropical city of Brisbane, Australia.

BACKGROUND: The relationship between temperature and mortality has been explored for decades and many temperature indicators have been applied separately. However, few data are available to show how the effects of different temperature indicators on different mortality categories, particularly in a typical subtropical climate. OBJECTIVE: To assess the associations between various temperature indicators and different mortality categories in Brisbane, Australia during 1996-2004. METHODS: We applied two methods to assess the threshold and temperature indicator for each age and death groups: mean temperature and the threshold assessed from all cause mortality was used for all mortality categories; the specific temperature indicator and the threshold for each mortality category were identified separately according to the minimisation of AIC. We conducted polynomial distributed lag non-linear model to identify effect estimates in mortality with one degree of temperature increase (or decrease) above (or below) the threshold on current days and lagged effects using both methods. RESULTS: Akaike's Information Criterion was minimized when mean temperature was used for all non-external deaths and deaths from 75 to 84 years; when minimum temperature was used for deaths from 0 to 64 years, 65-74 years, ≥ 85 years, and from the respiratory diseases; when maximum temperature was used for deaths from cardiovascular diseases. The effect estimates using certain temperature indicators were similar as mean temperature both for current day and lag effects. CONCLUSION: Different age groups and death categories were sensitive to different temperature indicators. However, the effect estimates from certain temperature indicators did not significantly differ from those of mean temperature.

Different inflections

Australia has often been defined by its landscape – actual, romanticized, imagined – iconic images and experiences taken up by artists in a myriad of ways. This paper examines inter/intra cultural practices of three Australian dance companies and their directors, and how they inflect images of Australia in different ways. Each artist brings perspectives from their particular hybridized cultural and ethnic backgrounds as well as their formative dance experiences. In their practices, notions of landscape embrace physical, metaphorical and spiritual dimensions. Kai Tai Chan, who founded the One Extra Company in 1976, pioneered accessible and confronting intercultural dance theatre in Australia from the 1970s to the 1990s, challenging our notions of what it is to be Australian. A Chinese Malay who came to Australia to study architecture, he stayed to create a significant body of work in which different cultural frameworks became lenses through which to explore stories of ordinary lives and experiences, revealing complexities of the human condition and larger social-political issues. Spiritual connections feature strongly in the practice of another Chinese Malay Australian, Tony Yap. Here the landscape is an inner one influenced by a form of Malaysian trance dance known as the sen-siao (“spirit cloud”) tradition. Yap has forged a unique space in the Australian dance and theatre scene, exploring a movement language informed by psycho-physical research, Asian shamanistic trance dance, Butoh, voice and visual design. Whilst primarily a solo performer, his practice includes collaborations with Asian diasporic as well as Anglo Australian cross-cultural visual and sound artists. His work is situated in a metaphysical rather than socio political context. In contrast, the newest company to emerge on the intercultural Australian stage is Polytoxic, reflecting a Pacific rather than Asian inflection. Key members, Fa’alafi and Efeso Fa’anana (both of Samoan descent) and Leah Shelton (of Anglo-Saxon descent), aim to critique the exoticism and cultural kitsch that often accompanies representations of the Pacific islands, with a pastiche of street dance, cabaret and contemporary techniques, blended with traditional Polynesian vocabulary. A parallel aim is to provide audiences with insights into the traditions and history of Samoa from the perspective of the artists as contemporary Australians. This examination, spanning three decades of inter/intra cultural practices, reveals stylistic, generational and philosophical differences with a commonality of variously inflected notions of landscape, spirituality and identity.

Non-pharmacological interventions for breathlessness management in patients with lung cancer : A systematic review

The aim is to review the published scientific literature for studies evaluating nonpharmacological interventions for breathlessness management in patients with lung cancer. The following selection criteria were used to systematically search the literature: studies were to be published research or systematic reviews; they were to be published in English and from 1990 to 2007; the targeted populations were adult patients with dyspnoea/breathlessness associated with lung cancer; and the study reported on the outcomes from use of non-pharmacological strategies for breathlessness. This review retrieved five studies that met all inclusion criteria. All the studies reported the benefits of non-pharmacological interventions in improving breathlessness regardless of differences in clinical contexts, components of programmes and methods for delivery. Analysis of the available evidence suggests that tailored instructions delivered by nurses with sufficient training and supervision may have some benefits over other delivery approaches. Based on the results, non-pharmacological interventions are recommended as effective adjunctive strategies in managing breathlessness for patients with lung cancer. In order to refine such interventions, future research should seek to explore the core components of such approaches that are critical to achieving optimal outcomes, the contexts in which the interventions are most effective, and to evaluate the relative benefits of different methods for delivering such interventions.

What do beginning English teachers want from professional development?

This qualitative, interpretive case study allows insights into the reflective emerging teacher practitioner as it explores pre-service and beginning teachers’ preparedness to deal with curriculum change and the demands of the classroom and school community. Five beginning teachers were asked what they want from professional development in a period of rapid curriculum change. The study aligns with emerging local and national agendas for teacher professional development and accreditation in Australia. The data analysis, based on “community of practice” perspectives, shows that new teachers have clear ideas about the professional development they need and want. Professional development is seen as integral to their developing professional identities. The paper has implications for the way leadership teams offer and how new teachers take up professional development opportunities, upon which registration is contingent.

Data modelling in the beginning school years

This paper argues for a renewed focus on statistical reasoning in the beginning school years, with opportunities for children to engage in data modelling. Some of the core components of data modelling are addressed. A selection of results from the first data modelling activity implemented during the second year (2010; second grade) of a current longitudinal study are reported. Data modelling involves investigations of meaningful phenomena, deciding what is worthy of attention (identifying complex attributes), and then progressing to organising, structuring, visualising, and representing data. Reported here are children's abilities to identify diverse and complex attributes, sort and classify data in different ways, and create and interpret models to represent their data.

Data modeling in elementary and middle school classes : a shared experience

This paper argues for a renewed focus on statistical reasoning in the elementary school years, with opportunities for children to engage in data modeling. Data modeling involves investigations of meaningful phenomena, deciding what is worthy of attention, and then progressing to organizing, structuring, visualizing, and representing data. Reported here are some findings from a two-part activity (Baxter Brown’s Picnic and Planning a Picnic) implemented at the end of the second year of a current three-year longitudinal study (grade levels 1-3). Planning a Picnic was also implemented in a grade 7 class to provide an opportunity for the different age groups to share their products. Addressed here are the grade 2 children’s predictions for missing data in Baxter Brown’s Picnic, the questions posed and representations created by both grade levels in Planning a Picnic, and the metarepresentational competence displayed in the grade levels’ sharing of their products for Planning a Picnic.

Engineering-based modelling experiences in the elementary classroom

Introducing engineering-based model-eliciting experiences in the elementary curriculum is a new and increasingly important domain of research by mathematics, science, technology, and engineering educators. Recent research has raised questions about the context of engineering problems that are meaningful, engaging, and inspiring for young students. In the present study an environmental engineering activity was implemented in two classes of 11-year-old students in Cyprus. The problem required students to develop a procedure for selecting among alternative countries from which to buy water. Students created a range of models that adequately solved the problem although not all models took into account all of the data provided. The models varied in the number of problem factors taken into consideration and also in the different approaches adopted in dealing with the problem factors. At least two groups of students integrated into their models the environmental aspect of the problem (energy consumption, water pollution) and further refined their models. Results indicate that engineering model-eliciting activities can be introduced effectively into the elementary curriculum, providing rich opportunities for students to deal with engineering contexts and to apply their learning in mathematics and science to solving real-world engineering problems.

Knowing about the English language: “a wrinkle in time”

Beryl & Gael discuss the ‘new’ metalanguage for knowledge about language presented in the Australian Curriculum English (ACARA, 2010). Their discussion connects to practice by recounting how one teacher scaffolds her students through detailed understandings of noun and adjective groups in reading activities. The stimulus text is the novel ‘A wrinkle in time’ (L’Engle, 1962, reproduced 2007) and the purpose is to build students’ understandings so they can work towards ‘expressing and developing ideas’ in written text (ACARA, 2010).

Parsing the Australian curriculum English : grammar, multimodality and cross-cultural texts

The release of the Australian Curriculum English (ACE) by the Australian Curriculum, Assessment and Reporting Authority (ACARA) has revived debates about the role of grammar as English content knowledge. We consider some of the discussion circulating in the mainstream media vis-à-vis the intent of the ACE. We conclude that this curriculum draws upon the complementary tenets of traditional Latin-based grammar and systemic functional linguistics across the three strands of Language, Literature and Literacy in innovative ways. We argue that such an approach is necessary for working with contemporary multimodal and cross-cultural texts. To demonstrate the utility of this new approach, we draw out a set of learning outcomes from Year 6 and then map out a framework for relating the outcomes to the form and function of multimodal language. As a case in point, our analysis is of two online Coca-Cola advertising texts, one each from South Korea and Australia.

Different kinds of openings of Luhmann's systems theory: A reply to la Cour et al

Various researchers have called for an 'opening up' of Luhmann's systems theory. We take this short paper as an occasion for a critical reflection on the necessity, existence and possibilities of such an opening. We start by pointing out the inherent openness of Luhmann's theory, and, based on this, discuss three kinds of openings: the international opening, the theoretical opening and the empirical opening. With regard to the latter, we distinguish three general options of using Luhmann's theory for empirical research. Copyright © 2007 SAGE.

Models of collective cell motion for cell populations with different aspect ratio : diffusion, proliferation and travelling waves

Continuum, partial differential equation models are often used to describe the collective motion of cell populations, with various types of motility represented by the choice of diffusion coefficient, and cell proliferation captured by the source terms. Previously, the choice of diffusion coefficient has been largely arbitrary, with the decision to choose a particular linear or nonlinear form generally based on calibration arguments rather than making any physical connection with the underlying individual-level properties of the cell motility mechanism. In this work we provide a new link between individual-level models, which account for important cell properties such as varying cell shape and volume exclusion, and population-level partial differential equation models. We work in an exclusion process framework, considering aligned, elongated cells that may occupy more than one lattice site, in order to represent populations of agents with different sizes. Three different idealizations of the individual-level mechanism are proposed, and these are connected to three different partial differential equations, each with a different diffusion coefficient; one linear, one nonlinear and degenerate and one nonlinear and nondegenerate. We test the ability of these three models to predict the population level response of a cell spreading problem for both proliferative and nonproliferative cases. We also explore the potential of our models to predict long time travelling wave invasion rates and extend our results to two dimensional spreading and invasion. Our results show that each model can accurately predict density data for nonproliferative systems, but that only one does so for proliferative systems. Hence great care must be taken to predict density data for with varying cell shape.

Teaching English : some remarks on the emergence of the sympathetic teacher in the English classroom

The chapter explores the concept of the teacher-student relationship within the English classroom and proposes that this relationship has a specific purpose in building a civil society by inculcating practices of self-reflection, empathy and ethics. The topic is explored through the example of teaching Australian literature, specifically, Tim Winton’s Lockie Leonard, Human Torpedo to secondary school students. Ian Hunter’s work on literature education and the construction of socio-ethical practices provides a conceptual framework for the chapter.

If things were different

In this video, a couple sits on a couch slowly breaking up. A typical shot/reverse-shot filmic structure is offset as the sound and image goes out of synch. At different times, it becomes so out of synch that they mouth each other’s words. This work engages with the signifying processes of romantic narratives. It emphasizes disruption and discontinuity as fundamental and generative operations in making meaning. Extending on post-structural and deconstructionist ideas, this work emphasizes the constructed nature of representations of heterosexual relationships. It draws attention to the gaps, slippages and fragments that pervade signifying acts.