Reconciling autonomy and beneficence in treatment decision-making for animal patients

This article explores how the concept of consent to medical treatment applies in the veterinary context, and aims to evaluate normative justifications for owner consent to treatment of animal patients. We trace the evolution of the test for valid consent in human health decision-making, against a backdrop of increased recognition of the importance of patient rights and a gradual judicial espousal of a doctrine of informed consent grounded in a particular understanding of autonomy. We argue that, notwithstanding the adoption of a similar discourse of informed consent in professional veterinary codes, notions of autonomy and informed consent are not easily transferrable to the veterinary medicine context, given inter alia the tripartite relationship between veterinary professional, owner and animal patient. We suggest that a more appropriate, albeit inexact, analogy may be drawn with paediatric practice which is premised on a similarly tripartite relationship and where decisions must be reached in the best interests of the child. However, acknowledging the legal status of animals as property and how consent to veterinary treatment is predicated on the animal owner’s willingness and ability to pay, we propose that the appropriate response is for veterinary professionals generally to accept the client’s choice, provided this is informed. Yet such client autonomy must be limited where animal welfare concerns exist, so that beneficence continues to play an important role in the veterinary context. We suggest that this ‘middle road’ should be reflected in professional veterinary guidance

A Study of Thermal Strains in Glass Fibre Reinforced Plastics.

The temperature dependence of the thermal strain in cross-ply glass fibre reinforced epoxy and polyester resin laminates has been determined from the deflection of unbalanced (0 /90) composite beams. These results have been compared with those predicted from measured values of the linear thermal expansion coefficients and moduli of the individual plies. For the epoxy resin based laminates good agreement was found between the experimental and calculated values. For the polyester resin based laminates, however, the predicted values considerably underestimated the experimentally determined thermal strain. The longitudinal and transverse expansion coefficients of dry post-cured unidirectional laminates made using these two resins were consistent with predictions from the Schapery equations, provided the temperature dependence of the resin expansion coefficient was allowed for. Small quantities of absorbed water were found to significantly increase the expansion coefficient of the polyester resin while leaving that of the epoxy resin unaffected. As a result of this effect fully post-cured polyester laminates containing absorbed water demonstrated a significant increase in the transverse expansion coefficient with little change in the longitudinal value. Using values of the thermal expansion coefficient for a polyester laminate containing 0.15 wt% water, good agreement between predicted and experimental values of thermal strain was obtained. Therefore the large thermal strains reported for polyester cross-ply laminates can be explained by small quantities of water in the matrix resin which is not readily removed during post-curing. The sensitivity of the polyester resin to such small quantities of absorbed water is considered to result from a two-phase microstructure consisting of highly cross-linked nodules in a less densely cross-linked matrix

A Study of Thermal Strains in Glass Fibre Reinforced Plastics.

The temperature dependence of the thermal strain in cross-ply glass fibre reinforced epoxy and polyester resin laminates has been determined from the deflection of unbalanced (0 /90) composite beams. These results have been compared with those predicted from measured values of the linear thermal expansion coefficients and moduli of the individual plies. For the epoxy resin based laminates good agreement was found between the experimental and calculated values. For the polyester resin based laminates, however, the predicted values considerably underestimated the experimentally determined thermal strain. The longitudinal and transverse expansion coefficients of dry post-cured unidirectional laminates made using these two resins were consistent with predictions from the Schapery equations, provided the temperature dependence of the resin expansion coefficient was allowed for. Small quantities of absorbed water were found to significantly increase the expansion coefficient of the polyester resin while leaving that of the epoxy resin unaffected. As a result of this effect fully post-cured polyester laminates containing absorbed water demonstrated a significant increase in the transverse expansion coefficient with little change in the longitudinal value. Using values of the thermal expansion coefficient for a polyester laminate containing 0.15 wt% water, good agreement between predicted and experimental values of thermal strain was obtained. Therefore the large thermal strains reported for polyester cross-ply laminates can be explained by small quantities of water in the matrix resin which is not readily removed during post-curing. The sensitivity of the polyester resin to such small quantities of absorbed water is considered to result from a two-phase microstructure consisting of highly cross-linked nodules in a less densely cross-linked matrix

Investigating the Impact of COVID-19 Disruption on the Decarbonisation Agenda at Airports: Grounded or Ready for Take-Off?

COVID-19 has had wide-ranging impacts on organisations with the potential to disrupt efforts to decarbonise their operations. To understand how COVID-19 has affected the climate change mitigation strategies of Airport Operators (AOs), questionnaires and semi-structured interviews with Sustainability Managers were undertaken in late 2020 amidst a period of disruption. While all reported that COVID-19 impacted delivery of interventions and projects to mitigate climate change, the majority stated that it would not impact their long-term climate goals, such as Net Zero by 2050. The most popular climate change mitigation interventions AOs intend to deploy between now and 2030 are on-site renewables and Electric Vehicles and related infrastructure. Engineered carbon removal interventions were considered highly unlikely to be deployed in this timeframe, with potential implications for Net Zero decarbonisation pathways. Despite the severe impacts of COVID-19 on the sector, results indicate that AOs remain committed to decarbonisation, with climate change action remaining the key priority for airports. Given ongoing financial and resource constraints, AOs will need to explore new business models and partnerships and nurture collaborative approaches with other aviation stakeholders to not only maintain progress toward Net Zero but “build back better”. Government support will also be needed to stimulate the development of a sustainable, resilient, low-carbon aviation system

Managing water infrastructure: Corrosion models for cast iron trunk mains

Distribution networks are critical in providing continuous potable water supplies to households and businesses. Trunk mains are the major arteries of the distribution network and convey large volumes of water over long distances. Worldwide, much of this infrastructure is made of ageing cast iron and is deteriorating at different rates. Many of these mains are beginning to approach the end of their service lives (with some already exceeding their design life) and consequently out of large populations of pipes, some are failing, although some still have considerable residual life. Trunk main failures can have significant social, health and safety, environmental and economic impacts. It is therefore imperative to prevent the wide-scale failure of trunk mains through the implementation of proactive asset management strategies. Such approaches require accurate condition assessment data across the network in conjunction with deterioration modelling to predict how the assets' condition and performance changes over time. This work, being part of a wider collaborative project, has outlined a deterioration modelling framework on the basis of existing physical probabilistic failure models and research focussing on residual mechanical properties, corrosion and the NDT detection of flaws. The developed deterioration model can be used to characterise individual pipes (deterministic approach), as well as the cohort/network modelling of pipes (probabilistic approach). Deterioration is assumed to be predominantly based on corrosion. Previously this has been dealt with in a rather simplistic manner. The broader work has, on the one hand,shown that corrosion mechanisms are rather different than previously thought and, on the other, that their effect on a given pipe can be variable. A corrosion model capable of simulating the distribution of corrosion properties of the primary defects is to be incorporated within the proposed modelling framework and the development of important aspects of this model are discussed here. © 2014 WIT Press

Managing water infrastructure: Corrosion models for cast iron trunk mains

Distribution networks are critical in providing continuous potable water supplies to households and businesses. Trunk mains are the major arteries of the distribution network and convey large volumes of water over long distances. Worldwide, much of this infrastructure is made of ageing cast iron and is deteriorating at different rates. Many of these mains are beginning to approach the end of their service lives (with some already exceeding their design life) and consequently out of large populations of pipes, some are failing, although some still have considerable residual life. Trunk main failures can have significant social, health and safety, environmental and economic impacts. It is therefore imperative to prevent the wide-scale failure of trunk mains through the implementation of proactive asset management strategies. Such approaches require accurate condition assessment data across the network in conjunction with deterioration modelling to predict how the assets' condition and performance changes over time. This work, being part of a wider collaborative project, has outlined a deterioration modelling framework on the basis of existing physical probabilistic failure models and research focussing on residual mechanical properties, corrosion and the NDT detection of flaws. The developed deterioration model can be used to characterise individual pipes (deterministic approach), as well as the cohort/network modelling of pipes (probabilistic approach). Deterioration is assumed to be predominantly based on corrosion. Previously this has been dealt with in a rather simplistic manner. The broader work has, on the one hand,shown that corrosion mechanisms are rather different than previously thought and, on the other, that their effect on a given pipe can be variable. A corrosion model capable of simulating the distribution of corrosion properties of the primary defects is to be incorporated within the proposed modelling framework and the development of important aspects of this model are discussed here. © 2014 WIT Press

Engineered cement composite materials characterisation for tunnelling applications

Cements, which are intrinsically brittle materials, can exhibit a degree of pseudo-ductility when reinforced with a sufficient volume fraction of a fibrous phase. This class of materials, called Engineered Cement Composites (ECC) has the potential to be used in future tunneling applications where a level of pseudo-ductility is required to avoid brittle failures. However uncertainties remain regarding mechanical performance. Previous work has focused on comparatively thin specimens; however for future civil engineering applications, it is imperative that the behavior in tension of thicker specimens is understood. In the present work, specimens containing cement powder and admixtures have been manufactured following two different processes and tested in tension. Multiple matrix cracking has been observed during tensile testing, leading to a “strain-hardening" behavior, confirming the possible suitability of ECC material when used as thick sections (greater than 50mm) in tunneling applications

Graphitic corrosion of cast iron trunk main: implications for asset management

Failures of (large diameter) cast iron trunk water mains can be catastrophic in the damage they can cause and it is therefore imperative to understand how cast iron deteriorates in order to help predict those areas of a water supply network which are at greatest risk of failure. Cast irons undergo a localized form of corrosion known as graphitic corrosion. Although a well reported phenomena, the mechanisms of graphitic corrosion are not fully understood. Scanning electron microscopy, in conjunction with energy dispersive x-ray spectroscopy, was used to characterise the microstructure and chemistry of the graphitic corrosion that occurs on the external surface of the pipe during time in service. It was found that that the graphite flakes within the cast iron are deteriorating during the corrosion process. High levels of chlorides are often found at the corrosion interface, within graphitic pits in the pipe wall. The implications of these observations on the development of models used to predict the remaining service life of buried trunk main are discussed

Treatment of problematic waste: a case study using wood

Waste is a complex societal problem: municipal solid waste (MSW) should be considered a resource, but the methods for capturing, treating, and utilising this resource are varied and often dependent on geopolitical factors. Previous research has, on the one hand explored the need for a more comprehensive waste composition specification in order to better manage municipal waste, and on the other focused on a problematic waste stream and the options available for dealing with it. The current work considers the use of multi-criteria decision making in order to assess the relative merits of different treatment options. A complex and problematic waste stream, wood, has been selected as a case study. For the purpose of the study, the work considers the options available to Surrey County Council in the UK. At the present time, for the conditions selected, energy from waste was considered to be the best option available for the treatment of wood with no discernible value for upcycling or reuse, but not contaminated with hazardous chemicals. When considering a different location with different circumstances, a different solution might be found