A simulation-based large deflection and inelastic analysis of steel frames under fire

This paper presents an accurate and robust geometric and material nonlinear formulation to predict structural behaviour of unprotected steel members at elevated temperatures. A fire analysis including large displacement effects for frame structures is presented. This finite element formulation of beam-column elements is based on the plastic hinge approach to model the elasto-plastic strain-hardening material behaviour. The Newton-Raphson method allowing for the thermal-time dependent effect was employed for the solution of the non-linear governing equations for large deflection in thermal history. A combined incremental and total formulation for determining member resistance is employed in this nonlinear solution procedure for the efficient modeling of nonlinear effects. Degradation of material strength with increasing temperature is simulated by a set of temperature-stress-strain curves according to both ECCS and BS5950 Part 8, which implicitly allows for creep deformation. The effects of uniform or non-uniform temperature distribution over the section of the structural steel member are also considered. Several numerical and experimental verifications are presented.

Using NVivo as a research management tool : a case narrative

This paper presents an illustrative demonstration of the qualitative data analysis tool NVivo (version 2.0), as employed across a multi-method research design as a comprehensive tool in support of overall research management. The paper will be of interest to (a) novice researchers, as a reference in their research design efforts; (b) academics, involved in research training, where this narrative can be used as a rich teaching case and; potentially to (c) vendors, of similar software tools, who may identify potential new tool applications and valuable tool enhancements.

Applying the ecological model of behavior change to a physical activity trial in retirement communities : description of the study protocol

Objectives To describe the intervention protocol for the first multilevel ecological intervention for physical activity in retirement communities that addresses individual, interpersonal and community influences on behavior change. Design A cluster randomized controlled trial design was employed with two study arms: a physical activity intervention and an attention control successful aging condition. Setting Sixteen continuing care retirement communities in San Diego County. Participants Three hundred twenty older adults, aged 65 years and older, are being recruited to participate in the trial. In addition, peer leaders are being recruited to lead some study activities, especially to sustain the intervention after study activities ceased. Intervention Participants in the physical activity trial receive individual, interpersonal and community intervention components. The individual level components include pedometers, goal setting and individual phone counseling. The interpersonal level components include group education sessions and peer-led activities. The community level components include resource audits and enumeration, tailored walking maps, and community improvement projects. The successful aging group receives individual and group attention about successful aging topics. Measurements The main outcome is light to moderate physical activity, measured objectively by accelerometry. Other objective outcomes included physical functioning, blood pressure, physical fitness, and cognitive functioning. Self report measures include depressive symptoms and health related quality of life. Results The intervention is being delivered successfully in the communities and compliance rates are high. Conclusion Ecological Models call for interventions that address multiple levels of the model. Previous studies have not included components at each level and retirement communities provide a model environment to demonstrate how to implement such an intervention.

Strategies and challenges for systematically mapping biologically significant molecular pathways regulating carcinoma epithelial-mesenchymal transition

Enormous progress has been made towards understanding the role of specific factors in the process of epithelial-mesenchymal transition (EMT); however, the complex underlying pathways and the transient nature of the transition continues to present significant challenges. Targeting tumour cell plasticity underpinning EMT is an attractive strategy to combat metastasis. Global gene expression profiling and high-content analyses are among the strategies employed to identify novel EMT regulators. In this review, we highlight several approaches to systematically interrogate key pathways involved in EMT, with particular emphasis on the features of multiparametric, high-content imaging screening strategies that lend themselves to the systematic discovery of highly significant modulators of tumour cell plasticity.

Student focus and prioritization of design parameters in first-year engineering design projects

BACKGROUND Research on engineering design is a core area of concern within engineering education and a fundamental understanding of how engineering students approach and undertake design is necessary in order to develop effective design models and pedagogies. Understanding the factors related to design experiences in education and how they affect student practice can help educators as well as designers to leverage these factors as part of the design process. PURPOSE This study investigated the design practices of first-year engineering students’ and their experiences with a first-year engineering course design project. The research questions that guided the investigation were: 1. From a student perspective, what design parameters or criteria are most important? 2. How does this perspective impact subsequent student design practice throughout the design process? DESIGN/METHOD The authors employed qualitative multi-case study methods (Miles & Huberman, 1994) in order to the answer the research questions. Participant teams were observed and video recorded during team design meetings in which they researched the background for the design problem, brainstormed and sketched possible solutions, as well as built prototypes and final models of their design solutions as part of a course design project. Analysis focused on explanation building (Yin, 2009) and utilized within-case and cross-case analysis (Miles & Huberman, 1994). RESULTS We found that students focused disproportionally on the functional parameter, i.e. the physical implementation of their solution, and the possible/applicable parameter, i.e. a possible and applicable solution that benefited the user, in comparison to other given parameters such as safety and innovativeness. In addition, we found that individual teams focused on the functional and possible/ applicable parameters in early design phases such as brainstorming/ ideation and sketching. When prompted to discuss these non-salient parameters (from the student perspective) in the final design report, student design teams often used a post-hoc justification to support how the final designs fit the parameters that they did not initially consider. CONCLUSIONS This study suggests is that student design teams become fixated on (and consequently prioritize) certain parameters they interpret as important because they feel these parameters were described more explicitly in terms how they were met and assessed. Students fail to consider other parameters, perceived to be less directly assessable, unless prompted to do so. Failure to consider other parameters in the early design phases subsequently affects their approach in design phases as well. Case studies examining students’ study strategies within three Australian Universities illustrate similarities with some student approaches to design.

Self in the City : Young Adult Fiction about New York City after 9/11

This chapter discusses fictional texts set in New York City soon after Septem- ber 11, 2001 (9/11), or whose characters are affected by the attacks on the World Trade Center. Whereas these texts may not have been directly marketed at young adults, they all address ‘youth issues’. Each of the books discussed here contain or are focalized through the eyes of adolescent protagonists. They are all coming-of-age narratives in that the crises within them are usually a result of a catastrophe, taking the characters on journeys of self-discovery, which, once fulfilled, lead them back home.1 As Jerry Griswold (1992) has suggested, coming-of-age stories are especially well suited to the American psyche, and are already familiar to readers of literature based in New York City (the most familiar work being J.D. Salinger’s The Catcher in the Rye). As with other clas- sic American young adult (YA) literature, the journey and homecoming com- monly associated with coming-of-age are often employed in fiction about 9/11. With the key elements of loss and suffering, self-awareness, introspection, and growth, the coming-of-age novel also fulfils agendas common to both litera- ture and politics: the literary journey becomes the nation’s journey.

Inter-sector senior leader transitions : experience and outcomes

Purpose The purpose of this article is to explore the experience of senior leaders who move into the public sector from other sectors of the economy, a process we refer to as inter-sector senior leader transitions. This is a little researched area of public sector leadership yet has significant implications for fundamental public sector reform. Design/methodology/approach We employed an interview design to elicit senior leaders' stories of their transition into the public sector. Findings The data suggest that successful senior leader transitions are more likely when a set of conditions is met; (1) the leader transitions into CEO role, rather than levels below CEO, (2) Ministers provide inter-sector transition support, (3) senior leaders develop responses to stress, (4) senior leaders reject high formalization, (5) their change processes focus on building capacity, and (6) senior leaders confront dysfunctional organizational relationships directly. Research limitations/implications The research relies on a relatively small sample. However, access to senior managers at this level can be difficult. Nevertheless, those senior managers who participated were very willing to share their stories. Practical implications If public sector organizations are to realize the value of successful leaders from other sectors, they need to invest in structured processes that facilitate the transition. A laissez-faire approach is not viable given the cost of such transitions. Originality/value The paper focuses on a little researched area of leadership experience which has significant implications for the development and change of the public sector.

The nature and correlates of young women's peer-directed protective behavioral strategies

Objective Recently, a number of studies have identified self-employed Protective Behavioral Strategies (PBS) as effective in decreasing the level of alcohol-related harm among young people. However, much of the published research has ignored important gender differences, such as women's increased tendency to rely on PBS that are social in nature. To further the understanding of women's PBS, the current study sought to investigate the nature and correlates of the strategies young women employ to keep their friends safe when drinking (i.e., peer-directed PBS). Method A scale measuring peer-directed PBS was developed and administered in conjunction with existing measures of alcohol consumption, personal PBS, and peer attachment. Participants consisted of 422 women aged 18–30 years, recruited among psychology students and the general public. Results Exploratory factor analysis revealed two clusters of peer-directed PBS; those that were aimed at reducing intoxication among one's friends and those that were designed to minimize alcohol-related harms. Further analysis found a positive relationship between women's tendency to implement personal and peer-directed PBS and that risky drinkers were less likely to engage in personal or peer-directed PBS (either type). Conclusion Findings indicate that personal and peer-directed PBS are related behaviors that are less frequently adopted by risky drinkers.

Sustainable creative career development pathways for young people in Tanzania : a case study

Tanzania has a rich and diverse cultural history based in community cultural life. However, at present, young people have limited opportunity to exploit this richness of traditional knowledge and engage in creative jobs as their means of future sustainable employment. Hence, the significant challenge remains: how to integrate and enhance the traditional knowledge in a learning strategy, while there is no “inter-ministerial action and institutional mechanisms” (United Nations 2008, 33-35) to promote creative employment for young people. This article reports on a case study that examined how the two Ministries of Culture and Education might work together to support Tanzania’s young people to secure, and engage successfully in creative jobs. The case study employed mixed methods, incorporating questionnaires, interviews and focus groups. The study was undertaken in Dar-Es-Salaam, Mwanza, Bagamoyo, Dodoma, Lindi and Morogoro from July to October, 2012. This paper discusses some of the issues and argues that there is no practical utilization of traditional knowledge and skills in “putting education to work” (UNESCO 2012, 170) for the better prospects of young people and to reveal the story of their lives. Although this study is specific to Tanzania, the case may also apply to other developing countries.

Error modeling and calibration of exteroceptive sensors for accurate mapping applications

Reliable robotic perception and planning are critical to performing autonomous actions in uncertain, unstructured environments. In field robotic systems, automation is achieved by interpreting exteroceptive sensor information to infer something about the world. This is then mapped to provide a consistent spatial context, so that actions can be planned around the predicted future interaction of the robot and the world. The whole system is as reliable as the weakest link in this chain. In this paper, the term mapping is used broadly to describe the transformation of range-based exteroceptive sensor data (such as LIDAR or stereo vision) to a fixed navigation frame, so that it can be used to form an internal representation of the environment. The coordinate transformation from the sensor frame to the navigation frame is analyzed to produce a spatial error model that captures the dominant geometric and temporal sources of mapping error. This allows the mapping accuracy to be calculated at run time. A generic extrinsic calibration method for exteroceptive range-based sensors is then presented to determine the sensor location and orientation. This allows systematic errors in individual sensors to be minimized, and when multiple sensors are used, it minimizes the systematic contradiction between them to enable reliable multisensor data fusion. The mathematical derivations at the core of this model are not particularly novel or complicated, but the rigorous analysis and application to field robotics seems to be largely absent from the literature to date. The techniques in this paper are simple to implement, and they offer a significant improvement to the accuracy, precision, and integrity of mapped information. Consequently, they should be employed whenever maps are formed from range-based exteroceptive sensor data. © 2009 Wiley Periodicals, Inc.

Trends in contact lens prescribing 2012

The 13th annual survey of Australian contact lens prescribing was conducted between January and April 2012. The same format as in previous years was employed. About 3,000 members of Optometrists Association Australia were sent an e-mail message with a link to a downloadable questionnaire, and a request that this be accessed, printed and completed to provide details of the first 10 patients fitted with contact lenses after receipt of the questionnaire.

Distinguishing between mechanisms of cell aggregation using pair-correlation functions

Many cell types form clumps or aggregates when cultured in vitro through a variety of mechanisms including rapid cell proliferation, chemotaxis, or direct cell-to-cell contact. In this paper we develop an agent-based model to explore the formation of aggregates in cultures where cells are initially distributed uniformly, at random, on a two-dimensional substrate. Our model includes unbiased random cell motion, together with two mechanisms which can produce cell aggregates: (i) rapid cell proliferation, and (ii) a biased cell motility mechanism where cells can sense other cells within a finite range, and will tend to move towards areas with higher numbers of cells. We then introduce a pair-correlation function which allows us to quantify aspects of the spatial patterns produced by our agent-based model. In particular, these pair-correlation functions are able to detect differences between domains populated uniformly at random (i.e. at the exclusion complete spatial randomness (ECSR) state) and those where the proliferation and biased motion rules have been employed - even when such differences are not obvious to the naked eye. The pair-correlation function can also detect the emergence of a characteristic inter-aggregate distance which occurs when the biased motion mechanism is dominant, and is not observed when cell proliferation is the main mechanism of aggregate formation. This suggests that applying the pair-correlation function to experimental images of cell aggregates may provide information about the mechanism associated with observed aggregates. As a proof of concept, we perform such analysis for images of cancer cell aggregates, which are known to be associated with rapid proliferation. The results of our analysis are consistent with the predictions of the proliferation-based simulations, which supports the potential usefulness of pair correlation functions for providing insight into the mechanisms of aggregate formation.

Bonding and bridging : transition to school and social capital formation among a community of Indigenous Australian children

This study reports on an intervention program designed to facilitate transition to school of a whole community of Indigenous Australian children who had previously not been attending. The children were from families displaced from their traditional lands and experienced on-going social marginalisation and transience. A social capital framework was employed to track change in the children’s social inclusion and family-school engagement for two years, from school entry. Sociometric measurement and interview techniques were applied to assess the children’s social connectedness and peer relationship quality. Using these data, analyses examined whether bonding within the group supported or inhibited formation of new social relationships. Although transience disrupted attendance, there was a group trend towards increased social inclusion with some evidence that group bonds supported bridging to new social relationships. Change in family-school engagement was tracked using multi-informant interviews. Limited engagement between school and families presented an on-going challenge to sustained educational engagement.

Retinal nerve fibre layer thickness is associated with higher risk of foot ulceration in diabetic peripheral neuropathy

Purpose To evaluate the association between retinal nerve fibre layer (RNFL) thickness and diabetic peripheral neuropathy in people with type 2 diabetes, and specifically those at higher risk of foot ulceration. Methods RNFL thicknesses was measured globally and in four quadrants (temporal, superior, nasal and inferior) at 3.45 mm diameter around the optic nerve head using optical coherence tomography (OCT). Severity of neuropathy was assessed using the Neuropathy Disability Score (NDS). Eighty-two participants with type 2 diabetes were stratified according to NDS scores (0-10) as: none, mild, moderate, and severe neuropathy. A control group was additionally included (n=17). Individuals with NDS≥ 6 (moderate and severe neuropathy) have been shown to be at higher risk of foot ulceration. A linear regression model was used to determine the association between RNFL and severity of neuropathy. Age, disease duration and diabetic retinopathy levels were fitted in the models. Independent t-test was employed for comparison between controls and the group without neuropathy, as well as for comparison between groups with higher and lower risk of foot ulceration. Analysis of variance was used to compare across all NDS groups. Results RNFL thickness was significantly associated with NDS in the inferior quadrant (b= -1.46, p=0.03). RNFL thicknesses globally and in superior, temporal and nasal quadrants did not show significant associations with NDS (all p>0.51). These findings were independent of the effect of age, disease duration and retinopathy. RNFL was thinner for the group with NDS ≥ 6 in all quadrants but was significant only inferiorly (p<0.005). RNFL for control participants was not significantly different from the group with diabetes and no neuropathy (superior p=0.07, global and all other quadrants: p>0.23). Mean RNFL thickness was not significantly different between the four NDS groups globally and in all quadrants (p=0.08 for inferior, P>0.14 for all other comparisons). Conclusions Retinal nerve fibre layer thinning is associated with neuropathy in people with type 2 diabetes. This relationship is strongest in the inferior retina and in individuals at higher risk of foot ulceration.

Australian baby boomers switched to more environment friendly modes of transport during the global financial crisis

The global financial crisis (GFC) in 2008 rocked local, regional, and state economies throughout the world. Several intermediate outcomes of the GFC have been well documented in the literature including loss of jobs and reduced income. Relatively little research has, however, examined the impacts of the GFC on individual level travel behaviour change. To address this shortcoming, HABITAT panel data were employed to estimate a multinomial logit model to examine mode switching behaviour between 2007 (pre-GFC) and 2009 (post-GFC) of a baby boomers cohort in Brisbane, Australia—a city within a developed country that has been on many metrics the least affected by the GFC. In addition, a Poisson regression model was estimated to model the number of trips made by individuals in 2007, 2008, and 2009. The South East Queensland Travel Survey datasets were used to develop this model. Four linear regression models were estimated to assess the effects of the GFC on time allocated to travel during a day: one for each of the three travel modes including public transport, active transport, less environmentally friendly transport; and an overall travel time model irrespective of mode. The results reveal that individuals were more likely to switch to public transport who lost their job or whose income reduced between 2007 and 2009. Individuals also made significantly fewer trips in 2008 and 2009 compared to 2007. Individuals spent significantly less time using less environmentally friendly transport but more time using public transport in 2009. Baby boomers switched to more environmentally friendly travel modes during the GFC.