Quantifying the Potential Scale of Mitigation Deterrence from Greenhouse Gas Removal Techniques

Greenhouse Gas Removal Techniques (GGR) appear to offer hopes of balancing limited global carbon budgets by removing substantial amounts of greenhouse gases from the atmosphere later this century. This hope rests on an assumption that GGR will largely supplement emissions reduction. The paper reviews the expectations of GGR implied by integrated assessment modelling, categorises ways in which delivery or promises of GGR might instead deter or delay emissions reduction, and offers a preliminary estimate of the possible extent of three such forms of ‘mitigation deterrence’. Type 1 is described as ‘substitution and failure’: an estimated 50-229 Gt-C (or 70% of expected GGR) may substitute for emissions otherwise reduced, yet may not be delivered (as a result of political, economic or technical shortcomings, or subsequent leakage or diversion of captured carbon into short-term utilization). Type 2, described as ‘rebounds’, encompasses rebounds, multipliers and side-effects, such as those arising from land-use change, or use of captured CO2 in enhanced oil recovery. A partial estimate suggests that this could add 25-134Gt-C to unabated emissions. Type 3, described as ‘imagined offsets’, is estimated to affect 17-27% of the emissions reductions required, reducing abatement by a further 182-297 Gt-C. The combined effect of these unanticipated net additions of CO2 to the atmosphere is equivalent to an additional temperature rise of up to 1.4°C. The paper concludes that such a risk merits further deeper analysis and serious consideration of measures which might limit the occurrence and extent of mitigation deterrence

A Study in the Theology of Dietrich Bonhoeffer With Particular Reference to Christian Spirituality

This thesis is a study in the theology of Dietrich Bonhoeffer with particular reference to Christian spirituality. There is a whole list of terms applicable to this notion. There is the 'spiritual life', 'spiritual outlook', and 'spiritual understanding. ' All of them suggest the notion of something esoteric, private, exclusive, separated from the generality of men, associated with a select few. This is an utter falsification of the position of Bonhoeffer. For him spirit is the ultimate reality. Spirituality implies engagement of the world in all its structures. The thesis examines this in the context of the whole theology of Bonhoeffer with particular reference to the Letters and Papers from Prison. The method employed stresses the element of synthesis found in Bonhoeffer's theology. Throughout the thesis reference is made to the synthesis of faith and worldliness, ultimate and penultimate. resistance and submission, and prayer and righteous action. The synthetic approach of Bonhoeffer to theological concepts is stressed in opposition to the dialectical theology of Karl Barth. Having examined and discussed the major areas in Bonhoeffer's theology the thesis concludes by drawing all these areas together into a structure of Christian Spirituality. Particular reference is made to the concept of the responsible deputy and the Church in an irreligious world. The fundamental structure of Christian Spirituality is defined in terms of being-there-for and with-others

Mirror, mirror:fairness and justice in climate geoengineering

Climate geoengineering seems an increasingly likely prospect as the gap between current mitigation action and that needed to avoid dangerous climate change remains substantial. Climate change raises fundamental questions of justice with respect to future generations, the poor and vulnerable in the contemporary world, and its relationship with processes of historically uneven development. The implications of geoengineering for prospects of justice in climate policy and politics are therefore critical. This thesis examines ways in which geoengineering might contribute to or undermine climate justice. It illustrates the co-productive, indeterminate, and inherently moral nature of technologies such as those proposed for geoengineering. It particularly highlights interactions between proposals for geoengineering and the politics and practice of climate mitigation and climate risk management, and explores some of the implications of different conceptions of fairness and justice and of different social and political imaginaries. The thesis locates this exploration of justice concerns in a case for a relational care-based imaginary of the future, rather than in (neo)liberal administrative, risk-managerial imaginaries based on autonomous subjects. It also defends a plural approach to justice rooted in environmental justice scholarship, arguing for the consistent inclusion of understandings of restorative and corrective justice alongside distributional, procedural and recognitional justice. The body of the thesis consists of five papers. Paper 1 locates the threat (and moral concern) of mitigation being deterred by climate engineering in a common but problematic definition of climate change as an issue of ‘climate risk’ rather than one of climate justice. Paper 2 suggests that even though climate engineering modellers sometimes broaden the understanding of the goals of climate policy to questions of distribution they tend to deploy a risk-analysis imaginary which imposes culturally, politically and ideologically narrow constructions of justice on the debate. Paper 3 finds that, in contrast, deliberative publics draw on a much broader set of justice concepts with regard to the uncertainties of climate change and geoengineering (including the prospects of mitigation deterrence). Paper 4 explores ways in which discourses of climate geoengineering are rooted in an administrative, risk-management social imaginary and support the maintenance of (neo)liberal capitalist economies through ‘post-political’ framings that increase the risk of mitigation deterrence. Paper 5 offers some alternative imaginaries through an examination of ethics of repair in potentially analogous arenas with relevant experience and debate. It illustrates how ethics of care, integrity and legibility, and the integration of restorative justice, would radically reframe ways of thinking about or practicing geoengineering. To indicate a pathway towards such a reconfiguration of imaginaries, the thesis proposes a new synthesis of approaches to justice as recognition that develops and further politicizes the account applied in environmental justice scholarship, transforming political subjectivity. In turn this underpins a conclusion that climate geoengineering, as currently proposed and framed, is inherently unjust and unfair, primarily because of the ways in which it could be expected to act to sustain neo-liberal administrative imaginaries and politics. In the worst case many existing injustices would be maintained and exacerbated, while the risk of actually catastrophic climate change increased

Modelling and analysis of next generation home networks

As Home Networking grows over the next 20 years the need for accurate models for both the network and the hardware becomes apparent. In this work, these two areas are considered together to develop a combined hardware and network model for a HomePlug power line based network. This change of focus is important when the type of devices that will be running on tomorrow's home network is considered. It will have evolved from a simple network of PCs sharing an Internet connection to a large heterogeneous structure of embedded System-on-Chip devices communicating on a variety of linked network technologies.This work presents a novel combined hardware and network modelling tool that address the following areas: 1. Development of a system level model of a HomePlug power-line based network, including the fundamental network protocols, the SoC hardware and the physical channel. 2. Use the developed model to explore various system scenarios. 3. Development of alternative hardware algorithms within the design. The model developed uses a Discrete Event simulation method to allow designers to explore areas such as: 1. How does the networking hardware (i.e. the components on the SoC) interact, and what are the issues of changing the algorithms. 2. I low do the nodes on the network interact, as the traffic patterns are different to those found on traditional (office-based) networks, as there will be a greater amount of streaming media

Whose climate and whose ethics?:Conceptions of justice in solar geoengineering modelling

The role of underlying assumptions about justice in the construction of climate geoengineering knowledge is explored, based on a review of climate modelling studies focused on stratospheric aerosol injection. Such emerging technologies would create distinctively new climates, closer to the present climate than those resulting from unabated emissions; but with different winners and losers, in part as a result of implications for energy systems. Embedded presuppositions about the nature and practice of modelling are exposed, as are unexplored and narrow utilitarian and distributional conceptions of justice. The implications of these underlying assumptions and values for the discourses of climate geoengineering are considered. It is argued that they obscure the identification and consideration of a range of potential injustices arising in the pursuit of climate geoengineering; and create and reproduce asymmetries in power regarding the discourses and evaluations of climate geoengineering prospects. In particular, optimistic climate geoengineering discourses risk sustaining elite interests in high-carbon energy economies. Some suggestions are offered to improve the design, deployment and interpretation of climate engineering models in trans-disciplinary research so as to mitigate these problems

Hardware accelerated image processing to enable real-time adaptive radiotherapy

The accuracy of radiotherapy is constrained by organ motion and deformation occurring between the acquisition of CT and MR images used to plan the treatment and the time at which the treatment is delivered. Adaptive radiotherapy uses image data acquired at the time of treatment to adapt the original treatment plan to match the current patient anatomy. Currently, the image processing and dose calculation algorithms required to perform this plan adaptation cannot be executed in a clinically acceptable timeframe. Hardware acceleration has the potential to speedup these algorithms, making real-time adaptive radiotherapy a clinical possibility[1]. Hardware acceleration is a technique where an algorithm is implemented using hardware that is better suited to the specific algorithm than more general purpose processors in order to reduce the execution time of the algorithm. This can be achieved using field programmable gate arrays (FPGA), which are devices consisting of reconfigurable hardware, allowing their function to be customised for a specific application. These devices have been shown to be able to accelerate image processing algorithms pertinent to adaptive radiotherapy[2]. In this study a global thresholding algorithm based on Otsu’s method combined with a three dimensional mean filter was used to segment a series of CT images of a Modus QUASAR respiratory motion phantom into three unique classes. A Xilinx Zynq Z-7020 device consisting of a dual-core ARM Cortex-A9 central processing unit (CPU) coupled to an 85 000 logic cell FPGA was used to accelerate the algorithm by implementing sections of it in the reconfigurable hardware. The execution time of this implementation was compared to an implementation running on an ARM CPU and Intel Core-i5 CPU. The execution times of the implementations are shown in table 1. The hardware accelerated implementation was found to execute nearly sixty times as fast as the un-accelerated algorithm. The hardware accelerated implementation was also found to run around 14% faster than on the more powerful Intel Core-i5 CPU. Figure 1 shows an example of the segmentation results where the blue contour represents the boundary between two of the classes. In the algorithms presented here the overhead of transferring data to the hardware represents a significant proportion of the algorithm execution time. It is anticipated that greater acceleration will be possible for algorithms with greater computational complexity because the data transfer overhead will represent a smaller proportion of the overall execution time. The requirement for fast processing in radiotherapy is likely to increase as the amount of data available to more accurately guide treatment increases through the use of techniques such as 4D CT and image-guided radiotherapy. FPGA have been shown to be effective at accelerating certain algorithms required for real-time adaptive radiotherapy, however, more research is required to establish which will execute faster on other types of hardware, such as CPU and graphical processing units (GPU). It is likely that heterogeneous computing platforms, composed of a mixture of hardware architectures, will be used in the future implementation of real-time adaptive radiotherapy. References: 1.K. Østergaard Noe, B.D. De Senneville, U.V. Elstrøm, K. Tanderup, T.S. Sørensen, “Acceleration and validation of optical flow based deformable registration for image-guided radiotherapy,” Acta Oncologica, vol. 47, no. 7, pp.1286-1293, 2008 2.O. Dandekar, R. Shekhar, “FPGA-Accelerated Deformable Image Registration for Improved Target-Delineation During CT-Guided Interventions,” IEEE Trans. Biomed. Circuits Syst., vol. 1, no. 2, pp.116-127, 200

Late Relapse and Follow-up Protocols in Testicular Germ Cell Tumours: The Edinburgh Cancer Centre Experience and Review of the Literature

Aims To identify clinicopathological features and outcomes in patients with late relapse (LR) of testicular germ cell tumours (GCTs) in order to guide follow-up policy. Materials and Methods The Edinburgh Cancer Centre (ECC) database identified all patients diagnosed with testicular GCT between 1988 and 2002. Of 703 patients, six relapsed more than 24 months after their initial treatment. A retrospective casenote review was performed to extract clinical, pathological, treatment and outcome data. Results Six patients (0.85%) underwent late relapse. All patients presented initially with stage I disease and five were classified as good risk (International Germ Cell Consensus Classification, IGCCC). Median time to LR was 31 months. Two patients had previously relapsed less than 24 months from initial diagnosis. Markers at the time of relapse were normal in all patients. In all cases of late relapse disease was confined to axial lymphadenopathy. Three patients were treated with chemotherapy alone, two patients underwent surgical resection and one patient received combined treatment. All patients obtained a complete response and all remain disease free with a median follow-up of 52 months. Conclusions The incidence of late relapse in this series is low. Chemo-naive patients with LR were successfully salvaged with chemotherapy alone and patients previously exposed to cisplatin-based chemotherapy were salvaged with complete surgical excision. The optimal length of follow-up in patients with testicular germ cell tumours is not known and practice varies widely. In this cohort of 703 patients, only one patient who relapsed was picked up by additional clinic follow-up between 5 and 10 years. Thus, on the basis of this small series, the authors suggest that follow-up after five years may not be justified

Local conflicts and national consensus:The strange case of circular economy in Sweden

Swedish press debate regarding the idea of a ‘circular economy’ is analysed to enable critical reflection on the development and use of the concept. We examine how actor positions formed around ideas of increased circularity. Using press material from 2012 to 2019 we identify positions on circular economy taken by Swedish companies, public authorities, political parties, and opinion makers. Our analysis reveals convergence amongst these actors at the national level despite ongoing situated local environmental conflicts. We show that this convergence is enabled by the convening power of ambiguity, which characterizes the use of circular economy ideas as a ‘floating signifier’ in the debate. In Sweden ideas of a circular economy may have been deployed by resilient capital to harness an otherwise economically disruptive process, as a new expression of ecological modernization. Further research into the political economy of circular economy ideas is encouraged