Characterization of in vitro Chlamydia muridarum persistence and utilization in an in vivo mouse model of Chlamydia vaccine

Problem: Chlamydia trachomatis genital tract infections are easily treated with antibiotics, however the majority of infections are asymptomatic and therefore untreated, highlighting the need for a vaccine. Because most infections are asymptomatic, vaccination could potentially be administered to individuals who may have an acute infection at that time. In such individuals the effect of vaccination on the existing infection is unknown; however one potential outcome could be the development of a persistent infection. In vitro chlamydial persistence has been well characterized in various strains, however there have been no reported studies in C. muridarum. Method of Study: We performed ultrastructural characterization, and transcriptome analysis of selected genes. We then used the transcriptional profiles of the selected genes to examine whether intranasal immunization of mice during an active genital infection would induce persistence in the upper reproductive tract of female mice. Results and Conclusions: We found that persistence developed in the oviducts of mice as a result of immunization. This is a significant finding, not only because it is the first time that C. muridarum persistence has been characterized in vitro, but also due to the fact that there is minimal characterization of in vivo persistence of any chlamydial species. This highlights the importance of the timing of vaccination in individuals.

A hierarchical structural model of assessing innovation and project performance

Research in construction innovation highlights construction industry as having many barriers and resistance to innovations and suggests that it needs champions. A hierarchical structural model is presented, to assess the impact of the role of the project manager (PM) on the levels of innovation and project performance. The model adopts the structural equation modelling technique and uses the survey data collected from PMs and project team members working for general contractors in Singapore. The model fits well to the observed data, accounting for 24%, 37% and 49% of the variance in championing behaviour, the level of innovation and project performance, respectively. The results of this study show the importance of the championing role of PMs in construction innovation. However, in order to increase their effectiveness, such a role should be complemented by their competency and professionalism, tactical use of influence tactics, and decision authority. Moreover, senior management should provide adequate resources and a sustained support to innovation and create a conducive environment or organizational culture that nurtures and facilitates the PM’s role in the construction project as a champion of innovation.

Sample selection in a model of female labour supply : an alternative approach

Suggests an alternative and computationally simpler approach of non-random sampling of labour economics and represents an observed outcome of an individual female′s choice of whether or not to participate in the labour market. Concludes that there is an alternative to the Heckman two-step estimator.

Numerical techniques for simulating a fractional mathematical model of epidermal wound healing

A number of mathematical models investigating certain aspects of the complicated process of wound healing are reported in the literature in recent years. However, effective numerical methods and supporting error analysis for the fractional equations which describe the process of wound healing are still limited. In this paper, we consider the numerical simulation of a fractional mathematical model of epidermal wound healing (FMM-EWH), which is based on the coupled advection-diffusion equations for cell and chemical concentration in a polar coordinate system. The space fractional derivatives are defined in the Left and Right Riemann-Liouville sense. Fractional orders in the advection and diffusion terms belong to the intervals (0, 1) or (1, 2], respectively. Some numerical techniques will be used. Firstly, the coupled advection-diffusion equations are decoupled to a single space fractional advection-diffusion equation in a polar coordinate system. Secondly, we propose a new implicit difference method for simulating this equation by using the equivalent of Riemann-Liouville and Grünwald-Letnikov fractional derivative definitions. Thirdly, its stability and convergence are discussed, respectively. Finally, some numerical results are given to demonstrate the theoretical analysis.

A finite element model of seat cushion indentation with a soft tissue human occupant model

Effective digital human model (DHM) simulation of automotive driver packaging ergonomics, safety and comfort depends on accurate modelling of occupant posture, which is strongly related to the mechanical interaction between human body soft tissue and flexible seat components. This paper presents a finite-element study simulating the deflection of seat cushion foam and supportive seat structures, as well as human buttock and thigh soft tissue when seated. The three-dimensional data used for modelling thigh and buttock geometry were taken on one 95th percentile male subject, representing the bivariate percentiles of the combined hip breadth (seated) and buttock-to-knee length distributions of a selected Australian and US population. A thigh-buttock surface shell based on this data was generated for the analytic model. A 6mm neoprene layer was offset from the shell to account for the compression of body tissue expected through sitting in a seat. The thigh-buttock model is therefore made of two layers, covering thin to moderate thigh and buttock proportions, but not more fleshy sizes. To replicate the effects of skin and fat, the neoprene rubber layer was modelled as a hyperelastic material with viscoelastic behaviour in a Neo-Hookean material model. Finite element (FE) analysis was performed in ANSYS V13 WB (Canonsburg, USA). It is hypothesized that the presented FE simulation delivers a valid result, compared to a standard SAE physical test and the real phenomenon of human-seat indentation. The analytical model is based on the CAD assembly of a Ford Territory seat. The optimized seat frame, suspension and foam pad CAD data were transformed and meshed into FE models and indented by the two layer, soft surface human FE model. Converging results with the least computational effort were achieved for a bonded connection between cushion and seat base as well as cushion and suspension, no separation between neoprene and indenter shell and a frictional connection between cushion pad and neoprene. The result is compared to a previous simulation of an indentation with a hard shell human finite-element model of equal geometry, and to the physical indentation result, which is approached with very high fidelity. We conclude that (a) SAE composite buttock form indentation of a suspended seat cushion can be validly simulated in a FE model of merely similar geometry, but using a two-layer hard/soft structure. (b) Human-seat indentation of a suspended seat cushion can be validly simulated with a simplified human buttock-thigh model for a selected anthropomorphism.

‘Working with the team’ : an exploratory study of improved type 2 diabetes management in a new model of integrated primary/secondary care

This study aimed to explore how a new model of integrated primary/secondary care for type 2 diabetes management, the Brisbane South Complex Diabetes Service (BSCDS), related to improved diabetes management in a selected group of patients. We used a qualitative research design to obtain detailed accounts from the BSCDS via semi-structured interviews with 10 patients. The interviews were fully transcribed and systematically coded using a form of thematic analysis. Participants’ responses were grouped in relation to: (1) Patient-centred care; (2) Effective multiprofessional teamwork; and (3) Empowering patients. The key features of this integrated primary/secondary care model were accessibility and its delivery within a positive health care environment, clear and supportive interpersonal communication between patients and health care providers, and patients seeing themselves as being part of the team-based care. The BSCDS delivered patient-centred care and achieved patient engagement in ways that may have contributed to improved type 2 diabetes management in these participants.

A tensor encoding model of word meaning : theory and application to information retrieval

This project was a step forward in developing and evaluating a novel, mathematical model that can deduce the meaning of words based on their use in language. This model can be applied to a wide range of natural language applications, including the information seeking process most of us undertake on a daily basis.

Numerical solution of an optimal control model of dendritic cell treatment of a growing tumour

A new optimal control model of the interactions between a growing tumour and the host immune system along with an immunotherapy treatment strategy is presented. The model is based on an ordinary differential equation model of interactions between the growing tu- mour and the natural killer, cytotoxic T lymphocyte and dendritic cells of the host immune system, extended through the addition of a control function representing the application of a dendritic cell treat- ment to the system. The numerical solution of this model, obtained from a multi species Runge–Kutta forward-backward sweep scheme, is described. We investigate the effects of varying the maximum al- lowed amount of dendritic cell vaccine administered to the system and find that control of the tumour cell population is best effected via a high initial vaccine level, followed by reduced treatment and finally cessation of treatment. We also found that increasing the strength of the dendritic cell vaccine causes an increase in the number of natural killer cells and lymphocytes, which in turn reduces the growth of the tumour.

A nurse-led model of oncogeriatric assessment

Background There is growing consensus that a multidisciplinary, comprehensive and standardised process for assessing the fitness of older patients for chemotherapy should be undertaken to determine appropriate cancer treatment. Aim This study tested a model of cancer care for the older patient incorporating Comprehensive Geriatric Assessment (CGA), which aimed to ensure that 'fit' individuals amenable to active treatment were accurately identified; 'vulnerable' patients more suitable for modified or supportive regimens were determined; and 'frail 'individuals who would benefit most from palliative regimens were also identified and offered the appropriate level of care. Methods A consecutive-series n=178 sample of patients >65 years was recruited from a major Australian cancer centre. The following instruments were administered by an oncogeriatric nurse prior to treatment: Vulnerable Elders Survey-13; Cumulative Illness Rating Scale (Geriatric); Malnutrition Screening Tool; Mini-mental State Examination; Geriatric Depression Scale; Barthel Index; and Lawton Instrumental Activities of Daily Living Scale. Scores from these instruments were aggregated to predict patient fitness, vulnerability or frailty for chemotherapy. Physicians provided a concurrent (blinded) prediction of patient fitness, vulnerability or frailty based on their clinical assessment. Data were also collected on actual patient outcomes (eg treatment completed as predicted, treatment reduced) during monthly audits of patient trajectories. Data analysis Data analysis is underway. A sample of 178 is adequate to detect, with 90% power, kappa coefficients of agreement between CGA and physician assessments of K>0.90 ("almost perfect agreement"). Primary endpoints comprise a) whether the nurse-led CGA determination of fit, vulnerable or frail agrees with the oncologist's assessments of fit, vulnerable or frail and b) whether the CGA and physician assessments accurately predict actual patient outcomes. Conclusion An oncogeriatric nurse-led model of care is currently being developed from the results. We conclude with a discussion of the pivotal role of nurses in CGA-based models of care.

Analysing the Sri Lankan conflict using Michael Mann's four-dimensional model of social power

This thesis provides an overview of the Sri Lankan civil war with a view to identifying some of the factors that contributed to the dispute between the Sri Lankan government and the Liberation Tigers of Tamil Eelam. It adopts a multi-causal explanation of the conflict by reference to the theories of social power developed by Michael Mann. The conflict has been variously described as an ethnic or political conflict, or has been characterised as a determined by a number of interacting factors (including colonialism, ethnicity, religion, economy, politics and globalisation). Mann’s four-dimensional model of social power is deployed to analyse the causal relationships, together with their inter-connections, which clarify the origins of the dispute. It argues that Mann’s theoretical framework helps to highlight some of the interconnected elements that contributed to the conflict.

Natural articular joints : model of lamellar-rollerbearing lubrication and the nature of the cartilage surface

The influence of pH on interfacial energy and wettability distributed over the phospholipid bilayer surface were studied, and the importance of cartilage hydrophobicity (wettability) on the coefficient of friction (f) was established. It is argued that the wettability of cartilage signifi antly depends on the number of phospholipid bilayers acting as solid lubricant; the hypothesis was proven by conducting friction tests with normal and lipid- depleted cartilage samples. A lamellar-roller-bearing lubrication model was devised involving two mechanisms: (i) lamellar frictionless movement of bilayers, and (ii) roller-bearing lubrication mode through structured synovial fluid, which operates when lamellar spheres, liposomes and macromolecules act like a roller-bearing situated between two cartilage surfaces in effective biological lubrication.

Hydrogeological framework, conceptual and numerical groundwater flow model of Laidley Creek catchment, Queensland, Australia

This thesis studies the water resources of Laidley Creek catchment within the Lockyer Valley where groundwater is used for intensive irrigation of crops. A holistic approach was used to consider groundwater within the total water cycle. The project mapped the geology, measured stream flows and groundwater levels, and analysed the chemistry of the waters. These data were integrated within a catchment-wide conceptual model, including historic and rainfall records. From this a numerical simulation was produced to test data validity and develop predictions of behaviour, which can support management decisions, particularly in times of variable climate.

Mathematical model of counter flow v-grove solar air collector

Double-pass counter flow v-grove collector is considered one of the most efficient solar air-collectors. In this design of the collector, the inlet air initially flows at the top part of the collector and changes direction once it reaches the end of the collector and flows below the collector to the outlet. A mathematical model is developed for this type of collector and simulation is carried out using MATLAB programme. The simulation results were verified with three distinguished research results and it was found that the simulation has the ability to predict the performance of the air collector accurately as proven by the comparison of experimental data with simulation. The difference between the predicted and experimental results is, at maximum, approximately 7% which is within the acceptable limit considering some uncertainties in the input parameter values to allow comparison. A parametric study was performed and it was found that solar radiation, inlet air temperature, flow rate and length has a significant effect on the efficiency of the air collector. Additionally, the results are compared with single flow V-groove collector.

To what extent is the Mayer and Salovey (1997) model of emotional intelligence a useful predictor of leadership style and perceived leadership outcomes in Australian educational institutions?

Researchers have found that transformational leadership is related to positive outcomes in educational institutions. Hence, it is important to explore constructs that may predict leadership style in order to identify potential transformational leaders in assessment and selection procedures. Several studies in non-educational settings have found that emotional intelligence is a useful predictor of transformational leadership, but these studies have generally lacked methodological rigor and contextual relevance. This project, set in Australian educational institutions, employed a more rigorous methodology to answer the question: to what extent is the Mayer and Salovey (1997) model of emotional intelligence a useful predictor of leadership style and perceived leadership outcomes? The project was designed to move research in the field forward by using valid and reliable instruments, controlling for other predictors, obtaining an adequately sized sample of current leaders and collecting multiple ratings of their leadership behaviours. The study (N = 144 leaders and 432 raters) results indicated that emotional intelligence was not a useful predictor of leadership style and perceived leadership outcomes. In contrast, several of the other predictors in the study were found to predict leadership style.