An effective approach to verbose queries using a limited dependencies language model

Intuitively, any `bag of words' approach in IR should benefit from taking term dependencies into account. Unfortunately, for years the results of exploiting such dependencies have been mixed or inconclusive. To improve the situation, this paper shows how the natural language properties of the target documents can be used to transform and enrich the term dependencies to more useful statistics. This is done in three steps. The term co-occurrence statistics of queries and documents are each represented by a Markov chain. The paper proves that such a chain is ergodic, and therefore its asymptotic behavior is unique, stationary, and independent of the initial state. Next, the stationary distribution is taken to model queries and documents, rather than their initial distri- butions. Finally, ranking is achieved following the customary language modeling paradigm. The main contribution of this paper is to argue why the asymptotic behavior of the document model is a better representation then just the document's initial distribution. A secondary contribution is to investigate the practical application of this representation in case the queries become increasingly verbose. In the experiments (based on Lemur's search engine substrate) the default query model was replaced by the stable distribution of the query. Just modeling the query this way already resulted in significant improvements over a standard language model baseline. The results were on a par or better than more sophisticated algorithms that use fine-tuned parameters or extensive training. Moreover, the more verbose the query, the more effective the approach seems to become.

Identifying with an avatar : a multidisciplinary perspective

Avatars perform a complex range of inter-related functions. They not only allow us to express a digital identity, they facilitate the expression of physical motility and, through non-verbal expression, help to mediate social interaction in networked environments. When well designed, they can contribute to a sense of “presence” (a sense of being there) and a sense of “co-presence” (a sense of being there with others) in digital space. Because of this complexity, the study of avatars can be enriched by theoretical insights from a range of disciplines. This paper considers avatars from the perspectives of critical theory, visual communication, and art theory (on portraiture) to help elucidate the role of avatars as an expression of identity. It goes on to argue that identification with an avatar is also produced through their expression of motility and discusses the benefits of film theory for explaining this process. Conceding the limits of this approach, the paper draws on philosophies of body image, Human Computer Interaction (HCI) theory on embodied interaction, and fields as diverse as dance to explain the sense of identification, immersion, presence and co-presence that avatars can produce.

'When everything old is new again' : class, consumerism and masculinity in Alasdair Duncan's Metro

Alasdair Duncan’s narrative Metro, set in Brisbane in the early twenty-first century, focuses on Liam, an unapologetically self-styled ‘white, upper middle-class brat’ whose sense of place and identity is firmly mapped by spatial and economic co-ordinates. This article considers the linkages between spatiality and identity in Duncan’s narrative, as well as the ways in which traditional, hegemonic (heterosexual) forms of masculinity are re-invigorated in the enactment of an upper-middle-class script of success, privilege and consumerism. It argues that the safeguarding of these hegemonic forms of masculine identity involves strategies of spatial and bodily expression underpinned by conspicuous consumption, relegating other forms of sexual identity to an exploitable periphery

The relationship between subjective appetite sensations, markers of inflammation and appetite in dialysis patients

Background: Poor appetite is a marker of morbidity and mortality in hemodialysis patients, making it an important area for research. Visual analog scales (VAS) can capture a range of subjective sensations related to appetite (such as hunger, desire to eat or fullness), but have not been commonly used to measure appetite in dialysis patients. The aim of this study was to explore the association between retrospective ratings of appetite using VAS and a range of clinical variables as well as biomarkers of appetite in hemodialysis patients.----- Methods: 28 hemodialysis patients (mean age 61±17y, 50% male, median dialysis vintage 19.5(4-101) months) rated their appetite using VAS for hunger, fullness and desire to eat and a 5-point categorical scale measuring general appetite. Blood levels of the appetite peptides leptin, ghrelin and peptide YY were also measured.----- Results: Hunger ratings measured by VAS were significantly (p<0.05) correlated with a range of clinical, nutritional and inflammatory markers: age (r=-0.376), co-morbidities, (r=-0.380) PG-SGA score (r=-0.451), weight (r=-0.375), fat-free mass (r=-0.435), C-Reactive Protein (CRP) (r=-0.383) and Intercellular adhesion molecule (sICAM-1) (r=-0.387). There was a consistent relationship between VAS and appetite on a 5-point categorical scale for questions of hunger, and a similar trend for desire to eat, but not for fullness. Neither method of measuring subjective appetite correlated with appetite peptides.----- Conclusions: Retrospective ratings of hunger on a VAS are associated with a range of clinical variables and further studies are warranted to support their use as a method of measuring appetite in dialysis patients.

Social innovation to solve homelessness : wicked solutions for wicked problems

Homelessness is a complex problem that manifests in all societies. This intractable and ‘wicked’ issue resists single-agency solutions and its resolution and requires a large, on-going investment of financial and professional resources that few organisations can sustain. This paper adopts a social innovation framework to examine government and community sector responses to homelessness. While recent evaluations and policy prescriptions have suggested better integrated and more co-ordinated service delivery models for addressing homelessness, there is little understanding of the innovation framework in which alternative service system paradigms emerge. A framework that identifies/distils and explains different innovation levels is put forward. The framework highlights that while government may lead strategic level innovations, community organisations are active in developing innovation at the service and client level. Moreover, community organisations may be unaware of the innovative capacity that resides in their creative responses to resolving social crisis and marginalisation through being without shelter.

Enabling authentic collaborative education in an online environment : the QUT Virtual Law Placement

This paper explores an innovative model for work-integrated learning using a virtual paradigm – The Virtual Law Placement Unit at Queensland University of Technology (QUT) Australia. It builds upon the conceptual model previously explored at WACE 2007 and provides an account of the lessons learned from the pilot offering of the unit which was conducted and evaluated in 2008. ----- The Virtual Placement Unit offers students the opportunity to complete an authentic workplace task under the guidance of a real-life workplace supervisor, where student-student communication and student-supervisor communication is all conducted virtually (and potentially asynchronously) to create an engaging but flexible learning environment using a combination of Blackboard and SharePoint technologies. This virtual experience is pioneering in the sense that it enables law students to access an unprecedented range of law graduate destination workplaces and projects, including international and social justice placements, absent the constraints traditionally associated with arranging physical placements. ----- All aspects of this unit have been designed in conjunction with community partners with a view to balancing student learning objectives with community needs through co-operative education. This paper will also explore how the implementation of the project is serving to strengthen those partnerships with the wider community, simultaneously addressing the community engagement agenda of the University and enabling students to engage meaningfully with local, national and international community partners in the real world of work.

User-designer collaboration during the early stage of the design process

As user involvement becomes a necessary part of the product development process, various ways of accessing users' latent needs have been developed and studied. Reviews of literatures in user involvement and product development have revealed that accessing users' latent needs and transferring them into design process could be facilitated by effectively implementing user-designer collaboration during the early stage of the design process. In this paper, various types of user-designer collaboration were observed and then distinct characteristics of user-designer collaboration were classified into three categories. 1) Passive objectivity, 2) workplace democratisation, and 3) shared contexts were observed as strategies for better user-designer collaboration, which have been employed in the area of user-centred design, user participatory design and design for experiencing. Based on the literature review, this paper proposed a basic collaboration mechanism between the users and the designers during the early stage of the design process and then discussed how its mechanism will help to describe the interactions between the users and the designers during the user involvement sessions.

Microstructural characterization of electron beam evaporated tungsten oxide films for gas sensing applications

Tungsten trioxide is one of the potential semiconducting materials used for sensing NH3, CO, CH4 and acetaldehyde gases. The current research aims at development, microstructural characterization and gas sensing properties of thin films of Tungsten trioxide (WO3). In this paper, we intend to present the microstructural characterization of these films as a function of post annealing heat treatment. Microstructural and elemental analysis of electron beam evaporated WO3 thin films and iron doped WO3 films (WO3:Fe) have been carried out using analytical techniques such as Transmission electron microscopy, Rutherford Backscattered Spectroscopy and XPS analysis. TEM analysis revealed that annealing at 300oC for 1 hour improves cyrstallinity of WO3 film. Both WO3 and WO3:Fe films had uniform thickness and the values corresponded to those measured during deposition. RBS results show a fairly high concentration of oxygen at the film surface as well as in the bulk for both films, which might be due to adsorption of oxygen from atmosphere or lattice oxygen vacancy inherent in WO3 structure. XPS results indicate that tungsten exists in 4d electronic state on the surface but at a depth of 10 nm, both 4d and 4f electronic states were observed. Atomic force microscopy reveals nanosize particles and porous structure of the film. This study shows e-beam evaporation technique produces nanoaparticles and porous WO3 films suitable for gas sensing applications and doping with iron decreases the porosity and particle size which can help improve the gas selectivity.

Porphyrins with metal, metalloid or phosphorus atoms directly bonded to the carbon periphery

Organometallic porphyrins with a metal, metalloid or phosphorus fragment directly attached to their carbon framework emerged for the first time in 1976, and these macrocycles have been intensively investigated in the past decade. The present review summarises for the first time all reported examples as well as applications of these systems.

In vitro and in vivo analysis of co-electrospun scaffolds made of medical grade poly(epsilon-caprolactone) and porcine collagen

In this study, a nanofiber mesh made by co-electrospinning medical grade poly(epsilon-caprolactone) and collagen (mPCL/Col) was fabricated and studied. Its mechanical properties and characteristics were analyzed and compared to mPCL meshes. mPCL/Col meshes showed a reduction in strength but an increase in ductility when compared to PCL meshes. In vitro assays revealed that mPCL/Col supported the attachment and proliferation of smooth muscle cells on both sides of the mesh. In vivo studies in the corpus cavernosa of rabbits revealed that the mPCL/Col scaffold used in conjunction with autologous smooth muscle cells resulted in better integration with host tissue when compared to cell free scaffolds. On a cellular level preseeded scaffolds showed a minimized foreign body reaction.