Fillers for improved graphite fiber retention by polymer matrix composites

The results of a program designed to determine the extent to which elemental boron and boron containing fillers added to the matrix resin of graphite/epoxy composites prevent the release of graphite fibers when the composites are exposed to fire and impact conditions are described. The fillers evaluated were boron, boron carbide and aluminum boride. The conditions evaluated were laboratory simulations of those that could exist in the event of an aircraft crash and burn situation. The baseline (i.e., unfilled) laminates evaluated were prepared from commercially available graphite/epoxy. The baseline and filled laminates' mechanical properties, before and after isothermal and humidity aging, also were compared. It was found that a small amount of graphite fiber was released from the baseline graphite/epoxy laminates during the burn and impact conditions used in this program. However, the extent to which the fibers were released is not considered a severe enough problem to preclude the use of graphite reinforced composites in civil aircraft structure. It also was found that the addition of boron and boron containing fillers to the resin matrix eliminated this fiber release. Mechanical properties of laminates containing the boron and boron containing fillers were lower than those of the baseline laminates. These property degradations for two systems: boron (5 micron) at 2.5 percent filler loading, and boron (5 micron) at 5.0 percent filler loading do not appear severe enough to preclude their use in structural composite applications

Digital literacy in practice: Developing an interactive and accessible open educational resource based on the SCONUL Seven Pillars of Information Literacy

As part of a review of the undergraduate and postgraduate curriculum at Leeds Metropolitan University, digital literacy was formally adopted as a graduate attribute in 2011. Libraries and Learning Innovation (LLI) have since been working on ways to improve the digital literacy of staff and students through a variety of means including promotion of Open Educational Resources (OER). This paper deals with one of those projects: the use of Xerte Online Toolkits (XOT) to create interactive resources which are supported by mobile devices. This ongoing project is truly collaborative, with members of academic staff and library staff (academic librarians, learning technologists and the repository developer) working together to create useful tools to support learning. The XOT project resulted from an audit by the university’s Open Educational Resources Group (led by LLI) which identified a need for mobile-friendly tutorials. From this, an interactive tutorial focussing on the SCONUL 7 Pillars of Information Literacy was developed. With the addition of new software to create interactive subject guides, the project aims to create more interactive resources to support students’ digital literacy

Spatial Interaction in Dynamic Urban Systems

It seems contradictory to model urban system change without considering changes in inter-urban interaction patterns, but this has frequently been the case in the urban literature. Consideration and explanation of changing interaction patterns is an area to which the "geographer's perspective" has much to contribute. Most explanations of city size distributions have ignored interactions and thus seem to be fundamentally in error. Short-term responses of cities to economic cycles may be identified and understood better by considering the inter-urban spacetime diffusion pattern of economic impulses. Long-term changes such as urban concentration and deconcentration can also be modeled with dynamic interactions. Among other conclusions it can be shown that unequal urban, and regional, growth rates are probable if interaction patterns are dynamic, even in the absence of economies of scale

Growth, Conflict and Crisis in the Urban System: A Neo-Marxian Approach to Modeling Inter-Urban Economic Dynamics

Many large urban agglomerations in the developed countries are either experiencing population decline or are growing at rates lower than those of middle-sized and small settlements. This trend is in direct contrast to the one for large cities in the less developed world, which are growing rapidly. Urban contraction and decline is generating fiscal pressures and fueling interregional conflicts in the developed nations; explosive city growth in the less developed world is creating problems of urban absorption. These developments call for the reformulation of urban policies based on an improved understanding of the dynamics that have produced the current patterns. During the period 1979-1982, the former Human Settlements and Services Area examined patterns of human settlement transformation as part of the research efforts of two tasks: the Urban Change Task and the Population, Resources, and Growth Task. This paper was written as part of that research activity. Its publication was delayed, and it is therefore being issued now a few months after the dissolution of the HSS Area

Maladaptive perfectionism and psychological distress:The mediating role of resilience and trait emotional intelligence

University students experience significantly high levels of psychological distress. Maladaptive perfectionism has been identified as a common trait among students that leads to diagnosed conditions such as depression and anxiety. Resilience and trait emotional intelligence have also been identified as common predictors of psychological illness and mediators between related maladaptive perfectionism. However, no current research has investigated maladaptive perfectionism’s relationship with a more general psychological distress experienced by university students. Therefore, the current study aimed to investigate maladaptive perfectionism, resilience and trait emotional intelligence association with psychological distress in 171 university students (29 males; 138 females; Mage = 28.48 years; SD = 11.58). Results identified maladaptive perfectionism to significantly, positively correlate with psychological distress in university students. The combination of increased maladaptive perfectionism, low resilience and low trait emotional intelligence significantly predicted psychological distress. Additionally, resilience and trait emotional intelligence significantly added to the prediction of psychological distress, above and beyond maladaptive perfectionism. Finally, resilience and trait emotional intelligence both partially mediated the relationship between maladaptive perfectionism and psychological distress in university students. Findings suggest resilience and trait emotional intelligence to be important factors in predicting general psychological distress in student maladaptive perfectionists. The current study provided additional supporting evidence for the importance of resilience and trait emotional intelligence in intervention and prevention strategies for psychological distress in maladaptive perfectionist students. </jats:p

On Forecasting Urban and Rural Populations: Some Methodological Reflections

Most attempts to forecast the proportions of a population that will be living in urban and rural areas use a model forecasting shifts between two homogeneous states: rural and urban (Ledent, 1980; United Nations, 1980). The aim of this short paper is to attempt to estimate how such forecasts must be corrected to account for the full complexity of a multiregional system, and to allow transitions from rural to urban areas over time. Purely demographic discrete time forecasts from an initial period T to some future period T, will be considered, and the effects of age distributions on migration and fertility rates will be neglected. Instead, attention will be focused on an issue emphasized elsewhere (Sheppard, 1980); that the dynamics of urbanization cannot be fully understood or predicted without allowing for the interdependencies between the various types of urban and rural areas; that is the full geography of population change. By introducing a methodology to correct forecasts in a way that allows for this, the importance of this full specification may be estimated

Developing the repository manager community

This paper describes activities which have taken place within the UK institutional repository (IR) sector focusing on developing a community of practice through the sharing of experiences and best practice. This includes work done by the UK Council of Research Repositories (UKCoRR) and other bodies, together with informal activities, such as sharing the experience of organising Open Access Week events. The paper also considers future work to be undertaken by UKCoRR to continue developing the community

Examining Pre-Service Teacher Candidates’ Sources and Levels of Knowledge about Autism Spectrum Disorders

This study was designed to identify what pre-service teacher candidates knew about autism spectrum disorder (ASD) and how they had acquired that knowledge in order to design more effective preparation courses. Teacher candidates (N=87) from three teacher preparation programs completed questionnaires during, or prior to, their first special education course. The findings indicate a relationship between sources of knowledge about ASD and actual levels of knowledge. Based on the findings, the authors argue that there is a need for coursework that focuses on effective intervention strategies and utilizes direct opportunities for teacher candidates to work with students with ASD

Geographies of Production I: Relationality revisited and the ‘practice shift’ in economic geography

This report considers recent developments and ongoing debates around relational economic geography, and a growing body work that has focused on economic practices as a means to better understand production processes and economic development. In particular it examines the critical reaction to relational thinking within the sub-discipline, and the nature of the debate about the degree to which relational work is - and needs to be - regarded as distinct from more traditional approaches to economic geography. It then considers how relational economic geography has become inflected towards an epistemological and methodological focus on practice. It argues that this engagement with economic practices provides the basis to respond to some of the limitations identified with earlier work, and opens up fruitful new potential for theorizing the nature of agency in the space economy