Using an individual-based model to select among alternative foraging strategies of woodpigeons: data support a memory-based model with a flocking mechanism

Population modelling is increasingly recognised as a useful tool for pesticide risk assessment. For vertebrates that may ingest pesticides with their food, such as woodpigeon (Columba palumbus), population models that simulate foraging behaviour explicitly can help predicting both exposure and population-level impact. Optimal foraging theory is often assumed to explain the individual-level decisions driving distributions of individuals in the field, but it may not adequately predict spatial and temporal characteristics of woodpigeon foraging because of the woodpigeons’ excellent memory, ability to fly long distances, and distinctive flocking behaviour. Here we present an individual-based model (IBM) of the woodpigeon. We used the model to predict distributions of foraging woodpigeons that use one of six alternative foraging strategies: optimal foraging, memory-based foraging and random foraging, each with or without flocking mechanisms. We used pattern-oriented modelling to determine which of the foraging strategies is best able to reproduce observed data patterns. Data used for model evaluation were gathered during a long-term woodpigeon study conducted between 1961 and 2004 and a radiotracking study conducted in 2003 and 2004, both in the UK, and are summarised here as three complex patterns: the distributions of foraging birds between vegetation types during the year, the number of fields visited daily by individuals, and the proportion of fields revisited by them on subsequent days. The model with a memory-based foraging strategy and a flocking mechanism was the only one to reproduce these three data patterns, and the optimal foraging model produced poor matches to all of them. The random foraging strategy reproduced two of the three patterns but was not able to guarantee population persistence. We conclude that with the memory-based foraging strategy including a flocking mechanism our model is realistic enough to estimate the potential exposure of woodpigeons to pesticides. We discuss how exposure can be linked to our model, and how the model could be used for risk assessment of pesticides, for example predicting exposure and effects in heterogeneous landscapes planted seasonally with a variety of crops, while accounting for differences in land use between landscapes.

The first real-time worldwide ionospheric predictions network: an advance in support of spaceborne experimentation, on-line model validation, and space weather

We report on the first realtime ionospheric predictions network and its capabilities to ingest a global database and forecast F-layer characteristics and "in situ" electron densities along the track of an orbiting spacecraft. A global network of ionosonde stations reported around-the-clock observations of F-region heights and densities, and an on-line library of models provided forecasting capabilities. Each model was tested against the incoming data; relative accuracies were intercompared to determine the best overall fit to the prevailing conditions; and the best-fit model was used to predict ionospheric conditions on an orbit-to-orbit basis for the 12-hour period following a twice-daily model test and validation procedure. It was found that the best-fit model often provided averaged (i.e., climatologically-based) accuracies better than 5% in predicting the heights and critical frequencies of the F-region peaks in the latitudinal domain of the TSS-1R flight path. There was a sharp contrast however, in model-measurement comparisons involving predictions of actual, unaveraged, along-track densities at the 295 km orbital altitude of TSS-1R In this case, extrema in the first-principle models varied by as much as an order of magnitude in density predictions, and the best-fit models were found to disagree with the "in situ" observations of Ne by as much as 140%. The discrepancies are interpreted as a manifestation of difficulties in accurately and self-consistently modeling the external controls of solar and magnetospheric inputs and the spatial and temporal variabilities in electric fields, thermospheric winds, plasmaspheric fluxes, and chemistry.

Metastatic melanoma positively influences pregnancy outcome in a mouse model: could a deadly tumor support embryo life?

The incidence of melanoma is increasing worldwide. It is one of the leading cancers in pregnancy and the most common malignancy to metastasize to placenta and fetus. There are no publications about experimental models of melanoma and pregnancy. We propose a new experimental murine model to study the effects of melanoma on pregnancy and its metastatic process. We tested several doses of melanoma cells until we arrived at the optimal dose, which produced tumor growth and allowed animal survival to the end of pregnancy. Two control groups were used: control (C) and stress control (SC) and three different routes of inoculation: intravenous (IV), intraperitoneal (IP) and subcutaneous (SC). All the fetuses and placentas were examined macroscopically and microscopically. The results suggest that melanoma is a risk factor for intrauterine growth restriction but does not affect placental weight. When inoculated by the SC route, the tumor grew only in the site of implantation. The IP route produced peritoneal tumoral growth and also ovarian and uterine metastases in 60% of the cases. The IV route produced pulmonary tumors. No placental or fetal metastases were obtained, regardless of the inoculation route. The injection of melanoma cells by any route did not increase the rate of fetal resorptions. Surprisingly, animals in the IV groups had no resorptions and a significantly higher number of fetuses. This finding may indicate that tumoral factors released in the host organism to favor tumor survival may also have a pro-gestational action and consequently improve the reproductive performance of these animals.

Process model to support data rich digital environments

This paper proposes a theoretical process model and the associated detailed information structure which reflects the complexity of information, stakeholder interaction and intellectual property concerns which are currently seen in the construction industry. This is being developed and tested against a field study renovation project. The field study project identifies information flows and interactions between stakeholders such as designers, project managers, clients, contractors, subcontractors and suppliers. The process model which is being established shows very high levels of complexity in dependencies and interdependencies between implicit and explicit information within the project design and construction teams. Without an understanding of these detailed and complex process interactions, proposals for the application of ICT to the construction industry will not reflect the requirements of those for whom they are being developed.

A process model to support design and construction

This research is focused on developing a highly detailed understanding of current organisational interactions and information flows leading to a definition of the process model for the environment into which information and communication technology (ICT) applications will be placed. The authors of this paper propose a theoretical process model and the associated detailed information structure which reflects the complexity of information, stakeholder interaction and intellectual property concerns which are currently seen in the construction industry. This is being developed and tested against a field study renovation project. The field study project identifies information flows and interactions between stakeholders such as designers, project managers, clients, contractors, subcontractors and suppliers. The process model which is being established shows very high levels of complexity in dependencies and interdependencies between implicit and explicit information within the project design and construction teams. Without an understanding of these detailed and complex process interactions, proposals for the application of ICT to the construction industry will not reflect the requirements of those for whom they are being developed.

An innovative spam filtering model based on support vector machine

Spam is commonly defined as unsolicited email messages and the goal of spam categorization is to distinguish between spam and legitimate email messages. Many researchers have been trying to separate spam from legitimate emails using machine learning algorithms based on statistical learning methods. In this paper, an innovative and intelligent spam filtering model has been proposed based on support vector machine (SVM). This model combines both linear and nonlinear SVM techniques where linear SVM performs better for text based spam classification that share similar characteristics. The proposed model considers both text and image based email messages for classification by selecting an appropriate kernel function for information transformation.

Retirement planning and expectations of Australian babyboomers

The "babyboomer" generation, those who were born between 1946 and 1965, account for over 30% of the population in Australia, and it is no surprise that the government is concerned about the financial implications for future healthcare costs. While many babyboomers are more financially secure than previous generations have been on account of compulsory superannuation contributions made over the past 15 years, there are still some who are financially vulnerable and expect to rely on government pensions and welfare assistance. Changes to family structures and job security also mean that those who are less financially secure will need social support. Using an ecological framework model , we explored the retirement expectations and experiences of some Australian babyboomers through focus groups and individual interviews to identify key issues and their plans to address these issues. Four main themes are reported in this paper: retirement attitudes and expectations, finances, health, and food. The results suggested that for many persons retirement equated freedom. Little future planning was undertaken for retirement other than contributing to superannuation schemes, and expectations were reported in general terms, such as wanting to remain independent and healthy and to have time to socialize and travel.

The development of a theoretical model for firm design management to support internationalisation processes

The aim of this research was to investigate strategies deployed by successful construction design related firms towards achieving high levels of firm competitiveness in international markets. A reflexive capability model, developed through a critical analysis of related internationalisation literature, is composed of three key areas; internationalisation process, market knowledge and design management. Firm reflexive capability is explored through the management of social, cultural and intellectual capital. The concept of reflexivity is borrowed from sociology the philosophers, Bourdieu and Giddens. Reflexivity is reinterpreted as the ‘firm’s’ ability to be aware, responsive and adaptable to self, market and project needs assessment. This research is part of an ongoing program of research on international collaborative practice. A Reflexive Capability Matrix is proposed. The reflexive capability approach is appropriate to all firms but what is speculated upon is that the reflexive capability is particularly applicable to small to medium sized construction design firms who work globally. A reflexive capability is a characteristic of successful and innovative firms internationalising and working within global models of practice. This paper is the theoretical development to support the paper in this congress “Design Management Methodology to Strengthen Firm and Industry Competitiveness in the Construction Design Services Export sector” where the methodology and results of a cross case analysis of three construction design firms are presented.

Towards the development of a project decision support framework for adoption of an integrated building information model using a model server

This chapter discusses an action research study towards the development of a decision framework to support a fully integrated multi disciplinary Building Information Model (BIM) using a Model Server. The framework was proposed to facilitate multi disciplinary collaborative BIM adoption through, informed selection of a project specific BIM approach and tools contingent upon project collaborators’ readiness, tool capabilities and workflow dependencies. The aim of the research was to explore the technical concerns in relation to Model Servers to support multi disciplinary model integration and collaboration; however it became clear that there were both technical and non technical issues that needed consideration. The evidence also suggests that there are varying levels of adoption which impacts upon further diffusion of the technologies. Therefore the need for a decision framework was identified based on the findings from an exploratory study conducted to investigate industry expectations. The study revealed that even the market leaders who are early technology adopters in the Australian industry in many cases have varying degrees of practical experiential knowledge of BIM and hence at times low levels of confidence of the future diffusion of BIM technology throughout the industry. The study did not focus on the benefits of BIM implementation as this was not the intention, as the industry partners involved are market leaders and early adopters of the technology and did not need convincing of the benefits. Coupled with this there are various other past studies that have contributed to the ‘benefits’ debate. There were numerous factors affecting BIM adoption which were grouped in to two main areas; technical tool functional requirements and needs, and non technical strategic issues. The need for guidance on where to start, what tools were available and how to work through the legal, procurement and cultural challenges was evidenced in the exploratory study. Therefore a BIM decision framework was initiated, based upon these industry concerns. Eight case studies informed the development of the framework and a summary of the key findings is presented. Primary and secondary case studies from firms that have adopted a structured approach to technology adoption are presented. The Framework consists of four interrelated key elements including a strategic purpose and scoping matrix, work process mapping, technical requirements for BIM tools and Model Servers, and framework implementation guide. The BIM framework was presented in draft format again to key industry stakeholders and considered in comparison with current best practice BIM adoption to further validate the framework. There was no request to change any part of the Framework. However, it is an ongoing process and it will be presented again to industry through the various project partners. The Framework may be refined within the boundaries of the action research process as an ongoing activity as more experiential knowledge can be incorporated.

Understanding exercise uptake and adherence for people with chronic conditions : a new model demonstrating the importance of exercise identity, benefits of attending and support

Understanding the factors influencing uptake and adherence to exercise for people with chronic conditions from different ages, genders and ethnicities is important for planning exercise services. This paper presents evidence supporting a new model of exercise uptake and adherence applicable to people with chronic conditions from diverse socio-demographic backgrounds. The study is based on 130 semistructured interviews with people with chronic conditions, including both those who did and those who did not attend exercise services, and supporters of those who attended. Analysis followed the guidelines of ‘framework analysis’. Results show that three factors were particularly important in influencing adherence behavior: (i) exercise identity, (ii) support and (iii) perceived benefits of attending. Social and cultural identities impacted on willingness to exercise, importance of exercise and perceived appropriateness of exercising. Having at least one supporter providing different types of support was associated with high levels of attendance. Those people who valued the social and psychological benefits of attending were more likely to be high attenders. The new model illustrates interaction between these three factors and discusses how these can be taken into account when planning exercise services for people with chronic conditions drawn from diverse socio-demographic groups.