Modelling the effects of bacterial cell state and spatial location on tuberculosis treatment: Insights from a hybrid multiscale cellular automaton model

This work was supported by the Medical Research Council [grant number MR/P014704/1] and the PreDiCT-TB consortium (IMI Joint undertaking grant agreement number 115337, resources of which are composed of financial contribution from the European Union’s Seventh Framework Programme (FP7/2007-2013) and EFPIA companies’ in kind contribution.If improvements are to be made in tuberculosis (TB) treatment, an increased understanding of disease in the lung is needed. Studies have shown that bacteria in a less metabolically active state, associated with the presence of lipid bodies, are less susceptible to antibiotics, and recent results have highlighted the disparity in concentration of different compounds into lesions. Treatment success therefore depends critically on the responses of the individual bacteria that constitute the infection. We propose a hybrid, individual-based approach that analyses spatio-temporal dynamics at the cellular level, linking the behaviour of individual bacteria and host cells with the macroscopic behaviour of the microenvironment. The individual elements (bacteria, macrophages and T cells) are modelled using cellular automaton (CA) rules, and the evolution of oxygen, drugs and chemokine dynamics are incorporated in order to study the effects of the microenvironment in the pathological lesion. We allow bacteria to switch states depending on oxygen concentration, which affects how they respond to treatment. This is the first multiscale model of its type to consider both oxygen-driven phenotypic switching of the Mycobacterium tuberculosis and antibiotic treatment. Using this model, we investigate the role of bacterial cell state and of initial bacterial location on treatment outcome. We demonstrate that when bacteria are located further away from blood vessels, less favourable outcomes are more likely, i.e. longer time before infection is contained/cleared, treatment failure or later relapse. We also show that in cases where bacteria remain at the end of simulations, the organisms tend to be slower-growing and are often located within granulomas, surrounded by caseous material.Publisher PDFPeer reviewe

Track E Implementation Science, Health Systems and Economics

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138412/1/jia218443.pd

A South African perspective on the existence of an interest tax shield

This paper investigates whether the use of debt in the capital structure of a company is beneficial to its shareholders. It finds that, in the South African context, gearing has no effect on the value of a company. The use of debt can increase the value of a company in a country where capital profits and interest are taxed equally. This is the result of an interest tax shield, which is directly related to the tax deductibility of interest paid. However, when capital growth and dividends are exempt in the hands of investors, as is the case in South Africa, the interest tax shield does not exist, and there appears to be no benefit in increasing debt

Radio transmitter implants in the horns of both the white and the black rhinoceros in the Kruger National Park

The procedure for implanting radio transmitters into the horns of white and black rhinoceroses is described. Mean transmitter life in the white rhinoceros was 13,9 months which is significantly longer than the 9,7 months in black rhinoceros. In the white rhinoceros a significant sex-related difference in transmitter life was found with the transmitters in males lasting a mean of 12,1 months compared to the 15,3 months in females

Transfer of employees from the public to the private sector : what are the issues to be addressed ?

Paper presented at the 20th Annual South African Transport Conference 16 - 20 July 2001 "Meeting the transport challenges in Southern Africa", CSIR International Convention Centre, Pretoria, South Africa.This paper was transferred from the original CD ROM created for this conference. The material on the CD ROM was published using Adobe Acrobat technology. The original CD ROM was produced by Document Transformation Technologies Postal Address: PO Box 560 Irene 0062 South Africa. Tel.: +27 12 667 2074 Fax: +27 12 667 2766 E-mail: [email protected] URL: http://www.doctech.co.z

Converging professional nurses’ perceptions and community service nurses’ experiences regarding clinical competence during community service placement

Background. Transitioning from a student to the role of a newly qualified nurse can be difficult when not well prepared. The expectation is that newly qualified nurses should reflect competency across a wide range of skills. To acquire and improve the necessary skills, many  countries opted to introduce and implement strategies to prepare nurses for their professional roles. In South Africa (SA), the newly qualified nurse is required to perform an obligatory 12 months’ community service as mandated by the regulation promulgated by the Minister of Health.Objective. To report the convergence results of the perceptions of professional nurses and the experiences of community service nurses (CSNs) regarding clinical competence of the latter during placement in North West Province (NWP), SA.Method. The study followed a qualitative, explorative, descriptive and contextual design. It employed the World Café data-collection method, including 21 purposively sampled participants. Benner’s levels of competence scale was used to rate the competence of CSNs. Pienaar’s four steps of qualitative thematic analysis were adapted to analyse data.Results. Three main themes emerged, i.e. ethos and professional practice; unit management, governance and leadership; and contextual clinical and technical competence.Conclusion. The World Café method allowed for real conversations around mutual topics of interest, and rich data collected is a true reflection of the participants’ perceptions and experiences. These results contributed to the development of a clinical competence evaluation tool for CSNs in NWP

A framework for the transfer of a departmental road construction unit to a private sector construction company

Paper presented at the 20th Annual South African Transport Conference 16 - 20 July 2001 "Meeting the transport challenges in Southern Africa", CSIR International Convention Centre, Pretoria, South Africa. ABSTRACT: The Northern Province Department of Public Works committed itself to improved service delivery. One of the most severe problems experienced by the Department is that the extent of personnel expenses are out of proportion when compared to other expenses. Personnel expenses can be reduced by outsourcing non-core functions of the department, for example road construction. In the case of the departmental road construction unit it has been decided to transfer the unit, including staff and equipment, to a suitable private sector construction company. The paper addresses the composition and performance of the road construction unit, staff issues and the interaction with organised labour, the invitation of expressions of interest from private sector road construction companies and the shortlisting of these companies for the tendering phase. A framework for the process of tendering for and implementation of the transfer of staff and equipment is then addressed. The transfer of the unit is linked to a road construction project, which will facilitate the merging of the unit into the organisation of the successful tenderer. As this is seen as a pilot project it is believed that similar projects will follow in future, and is it anticipated that the experience gained will be of value to those responsible for the implementation of similar projects.This paper was transferred from the original CD ROM created for this conference. The material on the CD ROM was published using Adobe Acrobat technology. The original CD ROM was produced by Document Transformation Technologies Postal Address: PO Box 560 Irene 0062 South Africa. Tel.: +27 12 667 2074 Fax: +27 12 667 2766 E-mail: [email protected] URL: http://www.doctech.co.z

Commercialisation of road maintenance in the western region of the Northern Province: a case study

Paper presented at the 20th Annual South African Transport Conference 16 - 20 July 2001 "Meeting the transport challenges in Southern Africa", CSIR International Convention Centre, Pretoria, South Africa.This paper was transferred from the original CD ROM created for this conference. The material on the CD ROM was published using Adobe Acrobat technology. The original CD ROM was produced by Document Transformation Technologies Postal Address: PO Box 560 Irene 0062 South Africa. Tel.: +27 12 667 2074 Fax: +27 12 667 2766 E-mail: [email protected] URL: http://www.doctech.co.z

Visit of the Principal, Prof C de la Rey to the UP Library, 18 June 2010

Library Mandate Mission, Vision, Values Library Strategies 2006-2010 Library structure Key strategies: Enable Teaching & Learning Enable Research e-Strategy Community & Professional engagement Quality Assurance & Staff development Strategic planning process: 2011-2015http://www.slideshare.net/heila1/visit-of-the-principal-prof-c-de-la-rey-to-the-up-library-18-june-201