Agarose gel as a soil analogue for the development of advanced bio-mediated soil improvement methods

Bio-mediated soil improvement methods (those that use biological processes) have potentially low cost and environmental impact but can be difficult to control to ensure effective results, especially if engineered bacteria are used. A novel application of using agarose gel as a soil analogue is proposed, which can enable development of advanced bio-mediated soil improvement methods by reproducing relevant mechanical properties while allowing complex biological processes to be studied in detail, before testing in soils. It is envisaged that agarose gel will be used instead of soil when developing early-stage prototype methods, as it provides an ideal environment to facilitate growth and monitoring of bacteria. A programme of geotechnical tests and Scanning Electron Microscopy on Agarose Low Melt (LM) gel is presented. The results demonstrate comparable pore size, undrained strength and permeability to soft clays and peats but more linear stress-strain behaviour and higher compressibility. This paper offers proof of this novel concept but further investigation is required as only a single type of agarose, at a single concentration is tested. By varying these factors, along with use of different solvents, there is significant potential to tune the behaviour of the analogue to particular soils or construction scenarios

Turbulent Casting: Bacterial Expression in Mineralized Structures

There has been a growing interest in living materials and fabrication processes including the use of bacteria, algae, fungi and yeast to offer sustainable alternatives to industrial materials synthesis. Microbially induced calcium carbonate precipitation (MICP) is a biomineralization process that has been widely researched to solve engineering problems such as concrete cracking and strengthen soils. MICP can also be used as an alternative to cement in the fabrication of building materials and, because of the unique process of living fabrication, if we see bacteria as our design collaborators new types of fabrication and process may be possible. The process of biomineralization is inherently different from traditional fabrication processes that use casting or molding. Its properties are influenced by the active bacterial processes that are connected to the casting environment. Understanding and working with interrelated factors enables a novel casting approach and the exploration of a range of form types and materials of variable consistencies and structure. We report an experiment with partial control of mineralization through the design of different experimental vessels to direct and influence the cementation process of sand. In order to capture the form of the calcification in these experiments, we have analyzed the results using three-dimensional imaging and a technique which excavates the most friable material from the cast in stages. The resulting scans are used to reconstruct the cementation timeline. This reveals a hidden fabrication/growth process. These experiments offer a different perspective on form finding in material fabrication

The role of emergent champions in policy implementation for decentralised drug-resistant tuberculosis care in South Africa.

OBJECTIVE: Champions are recognised as important to driving organisational change in healthcare quality improvement initiatives in high-income settings. In low-income and middle-income countries with a high disease burden and constrained human resources, their role is highly relevant yet understudied. Within a broader study on policy implementation for decentralised drug-resistant tuberculosis care in South Africa, we characterised the role, strategies and organisational context of emergent policy champions. DESIGN: Interviews with 34 healthcare workers in three South African provinces identified the presence of individuals who had a strong influence on driving policy implementation forward. Additional interviews were conducted with 13 participants who were either identified as champions in phase II or were healthcare workers in facilities in which the champions operated. Thematic analyses using a socio-ecological framework further explored their strategies and the factors enabling or obstructing their agency. RESULTS: All champions occupied senior managerial posts and were accorded legitimacy and authority by their communities. 'Disease-centred' champions had a high level of clinical expertise and placed emphasis on clinical governance and clinical outcomes, while 'patient-centred' champions promoted pathways of care that would optimise patients' recovery while minimising disruption in other spheres of their lives. Both types of champions displayed high levels of resourcefulness and flexibility to adapt strategies to the resource-constrained organisational context. CONCLUSION: Policymakers can learn from champions' experiences regarding barriers and enablers to implementation to adapt policy. Research is needed to understand what factors can promote the sustainability of champion-led policy implementation, and to explore best management practices to support their initiatives

The role of emergent champions in policy implementation for decentralised drug-resistant tuberculosis care in South Africa

From BMJ via Jisc Publications RouterHistory: received 2022-02-24, accepted 2022-11-07, ppub 2022-12, epub 2022-12-09Peer reviewed: TrueAcknowledgements: This paper draws on data from a 4-year project that aimed to gain an understanding of the policy context, patient care pathways and models of decentralisation of DR-TB care in three South African provinces. The authors would like to thank and acknowledge Dr Norbert Ndjeka (SA NDOH), key informants, staff and participants interviewed and the provinces of the Western Cape, Eastern Cape, KwaZulu-Natal for all their time, critical insights and assistance.Publication status: PublishedFunder: Medical Research Council; FundRef: http://dx.doi.org/10.13039/501100000265; Grant(s): MR/N015924/1Karina Kielmann - ORCID: 0000-0001-5519-1658 https://orcid.org/0000-0001-5519-1658Objective: Champions are recognised as important to driving organisational change in healthcare quality improvement initiatives in high-income settings. In low-income and middle-income countries with a high disease burden and constrained human resources, their role is highly relevant yet understudied. Within a broader study on policy implementation for decentralised drug-resistant tuberculosis care in South Africa, we characterised the role, strategies and organisational context of emergent policy champions. Design: Interviews with 34 healthcare workers in three South African provinces identified the presence of individuals who had a strong influence on driving policy implementation forward. Additional interviews were conducted with 13 participants who were either identified as champions in phase II or were healthcare workers in facilities in which the champions operated. Thematic analyses using a socio-ecological framework further explored their strategies and the factors enabling or obstructing their agency. Results: All champions occupied senior managerial posts and were accorded legitimacy and authority by their communities. ‘Disease-centred’ champions had a high level of clinical expertise and placed emphasis on clinical governance and clinical outcomes, while ‘patient-centred’ champions promoted pathways of care that would optimise patients’ recovery while minimising disruption in other spheres of their lives. Both types of champions displayed high levels of resourcefulness and flexibility to adapt strategies to the resource-constrained organisational context. Conclusion: Policymakers can learn from champions’ experiences regarding barriers and enablers to implementation to adapt policy. Research is needed to understand what factors can promote the sustainability of champion-led policy implementation, and to explore best management practices to support their initiatives.pubpu

Organisation of care for people receiving drug-resistant tuberculosis treatment in South Africa: a mixed methods study

From BMJ via Jisc Publications RouterHistory: received 2023-03-03, accepted 2023-10-09, ppub 2023-11, epub 2023-11-18Peer reviewed: TrueAcknowledgements: The authors wish to thank the Departments of Health of the Western Cape, Eastern Cape, KwaZulu-Natal, and acknowledge the staff at the NHLS for their tremendous input and assistance. We give special mention to the late Dr Iqbal Masters and Mrs Anna Maria Evans for their contributions to the study. We also appreciate the support of Staff Nurse Cheryl Liedeman and Dr Widaad Zemanay.Publication status: PublishedFunder: Medical Research Council; FundRef: http://dx.doi.org/10.13039/501100000265; Grant(s): MR/N015924/1Funder: Wellcome Trust; FundRef: http://dx.doi.org/10.13039/100010269; Grant(s): MR/N015924/1Funder: Australian National Health and Medical Research Council; Grant(s): APP1174455Karina Kielmann - ORCID: 0000-0001-5519-1658 https://orcid.org/0000-0001-5519-1658Objectives: Treatment for multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) is increasingly transitioning from hospital-centred to community-based care. A national policy for decentralised programmatic MDR/RR-TB care was adopted in South Africa in 2011. We explored variations in the implementation of care models in response to this change in policy, and the implications of these variations for people affected by MDR/RR-TB. Design: A mixed methods study was done of patient movements between healthcare facilities, reconstructed from laboratory records. Facility visits and staff interviews were used to determine reasons for movements. Participants and setting: People identified with MDR/RR-TB from 13 high-burden districts within South Africa. Outcome measures: Geospatial movement patterns were used to identify organisational models. Reasons for patient movement and implications of different organisational models for people affected by MDR/RR-TB and the health system were determined. Results: Among 191 participants, six dominant geospatial movement patterns were identified, which varied in average hospital stay (0–281 days), average patient distance travelled (12–198 km) and number of health facilities involved in care (1–5 facilities). More centralised models were associated with longer delays to treatment initiation and lengthy hospitalisation. Decentralised models facilitated family-centred care and were associated with reduced time to treatment and hospitalisation duration. Responsiveness to the needs of people affected by MDR/RR-TB and health system constraints was achieved through implementation of flexible models, or the implementation of multiple models in a district. Conclusions: Understanding how models for organising care have evolved may assist policy implementers to tailor implementation to promote particular patterns of care organisation or encourage flexibility, based on patient needs and local health system resources. Our approach can contribute towards the development of a health systems typology for understanding how policy-driven models of service delivery are implemented in the context of variable resources.pubpu

Organisation of care for people receiving drug-resistant tuberculosis treatment in South Africa: a mixed methods study.

OBJECTIVES: Treatment for multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) is increasingly transitioning from hospital-centred to community-based care. A national policy for decentralised programmatic MDR/RR-TB care was adopted in South Africa in 2011. We explored variations in the implementation of care models in response to this change in policy, and the implications of these variations for people affected by MDR/RR-TB. DESIGN: A mixed methods study was done of patient movements between healthcare facilities, reconstructed from laboratory records. Facility visits and staff interviews were used to determine reasons for movements. PARTICIPANTS AND SETTING: People identified with MDR/RR-TB from 13 high-burden districts within South Africa. OUTCOME MEASURES: Geospatial movement patterns were used to identify organisational models. Reasons for patient movement and implications of different organisational models for people affected by MDR/RR-TB and the health system were determined. RESULTS: Among 191 participants, six dominant geospatial movement patterns were identified, which varied in average hospital stay (0-281 days), average patient distance travelled (12-198 km) and number of health facilities involved in care (1-5 facilities). More centralised models were associated with longer delays to treatment initiation and lengthy hospitalisation. Decentralised models facilitated family-centred care and were associated with reduced time to treatment and hospitalisation duration. Responsiveness to the needs of people affected by MDR/RR-TB and health system constraints was achieved through implementation of flexible models, or the implementation of multiple models in a district. CONCLUSIONS: Understanding how models for organising care have evolved may assist policy implementers to tailor implementation to promote particular patterns of care organisation or encourage flexibility, based on patient needs and local health system resources. Our approach can contribute towards the development of a health systems typology for understanding how policy-driven models of service delivery are implemented in the context of variable resources

Design and modelling of an engineered bacteria-based, pressure-sensitive soil.

In this paper, we describe the first steps in the design of a synthetic biological system based on the use of genetically modified bacteria to detect elevated pressures in soils and respond by cementing soil particles. Such a system might, for example, enable a self- constructed foundation to form in response to load using engineered bacteria which could be seeded and grown in the soils. This process would reduce the need for large-scale excavations and may be the basis for a new generation of self-assembling and responsive bio-based materials. A prototype computational model is presented which integrates experimental data from a pressure sensitive gene within Escherichia coli bacteria with geotechnical models of soil loading and pore water pressure. The results from the integrated model are visualised by mapping expected gene expression values onto the soil volume. We also use our experimental data to design a two component system where one type of bacteria acts as a sensor and signals to another material synthesis bacteria. The simulation demonstrates the potential of computational models which integrate multiple scales from macro stresses in soils to the expression of individual genes to inform new types of design process. The work also illustrates the combination of in silico (silicon based computing) computation with in vivo (in the living) computation

Liquefaction remediation techniques for existing buildings

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Synthetic Biological Construction: Beyond ‘bioinspired’ in the design of new materials and fabrication systems

This paper introduces the concept of Synthetic Biological Construction through our project Computational Colloids. The paper suggests a framework for Synthetic Biology to be integrated with Civil Engineering. Through in vivo (in the living) and in silico (digital computational) work, we describe the first steps towards a system that integrates the analysis and synthesis of material construction through engineered biological agents. It is proposed here that such a system would lead to a new paradigm in engineering design