Can geoengineering be optimised?

Geoengineering is the intentional, large-scale manipulation of Earth’s climate. It has been suggested that this could be done to counteract or ameliorate the effects of anthropogenic climate change, to reduce its negative impacts or buy time for global greenhouse gas emissions to be reduced. Stratospheric aerosol injection, where aerosols in the stratosphere are used to reflect sunlight and so cool climate, has been widely studied. Altering the altitude, latitude, or timing of aerosol injections could result in different radiative forcing patterns, which suggests there may be potential to “optimise” stratospheric aerosol injection geoengineering to achieve particular climate goals. The extent to which geoengineering could be optimised, beyond idealised studies that counteract the global mean temperature increase of greenhouse gases, has only relatively recently begun to be explored. Chapter 1 discusses the background of geoengineering as a concept and includes a literature review and discussion of robust results that have emerged from modelling studies of geoengineering. Chapter 2 uses a combination of analytical techniques and the simple climate model, FaIR, to examine different scenarios for “peak-shaving” – temporarily using geoengineering to hold global mean temperatures below a certain threshold – and examines trade-offs between the amount of warming avoided and the implied duration of commitment to geoengineering. Chapters 3-5 analyse simulations from the HadCM3 climate model, simulated using climateprediction.net, which uses thousands of volunteer computers to generate large ensembles of simulations with differing distributions of stratospheric aerosol optical depth counteracting an abrupt quadrupling of carbon dioxide to represent different attempts at tailoring geoengineering. Chapter 3 details initial calibration and characterisation of the response to simple patterns of radiative forcing, and establishes that the temperature response to different patterns of forcing is, to a good approximation, linear and additive. Chapter 4 expands on this and discusses various methods for optimising for temperature and precipitation, including analysis of trade-offs for attempting to optimise temperature in different regions, and analysis of whether there are a limited number of fundamental modes of response in the HadCM3 climate model to a range of imposed radiative forcing patterns. Chapter 5 examines the impact of geoengineering on climate and weather extremes, using metrics that represent heatwaves, flooding, and dry periods, and analysing any differences in the distribution of extreme events between simulations of the preindustrial and geoengineered climates. In the final chapter, results and conclusions are summarised, and possible future work is outlined

Recreational use of the countryside: No evidence that high nature value enhances a key ecosystem service

In Western Europe, recreational amenity is presented as an important cultural ecosystem service that, along with other values, helps justify policies to conserve biodiversity. However, whether recreational use by the public is enhanced at protected areas designated for nature conservation is unknown. This is the first study to model outdoor recreation at a national scale, examining habitat preferences with statutory designation (Site of Special Scientific Interest) as an indicator of nature conservation importance. Models were based on a massive, three year national household survey providing spatially-referenced recreational visits to the natural environment. Site characteristics including land cover were compared between these observed visit sites (n = 31,502) and randomly chosen control sites (n = 63,000). Recreationists preferred areas of coast, freshwater, broadleaved woodland and higher densities of footpaths and avoided arable, coniferous woodland and lowland heath. Although conservation designation offers similar or greater public access than undesignated areas of the same habitat, statutory designation decreased the probability of visitation to coastal and freshwater sites and gave no effect for broadleaved woodland. Thus general recreational use by the public did not represent an important ecosystem service of protected high-nature-value areas, so that intrinsic and existence values remain as the primary justifications for conservation of high nature value areas. Management of ‘green infrastructure’ sites of lower conservation value that offer desirable habitats and enhanced provision of footpaths, could mitigate recreational impacts on nearby valuable conservation areas

Modelling nature-based recreation to inform land management

Countryside recreation is hugely popular and demand is on the rise. Whilst participation should be encouraged, sensitive management is required to reduce associated environmental impacts. This thesis investigates current and future patterns in countryside recreation at multiple spatial scales, from national to site, to explore the potential impacts on biodiversity and enhance the evidence base for conservation interventions. A national-level recreation model is developed from a unique and massive data set of georeferenced recreational visits collected over 3 years, which predicts the probability of visitation as a function of land cover composition and accessibility to and within a site, whilst controlling for source population and socio-demographic differences. Land cover types were subdivided into proportion designated and non-designated for high nature value, using Sites of Special Scientific Interest (SSSI) as a proxy. Probability of visitation to preferred land covers, coast and freshwater, decreased when SSSI designated, with no effect for broadleaved woodland. Therefore general recreational use by the public did not represent an important ecosystem service of protected high-nature-value areas. The model was employed to create national- and county-level spatially-explicit predictions of countryside recreation under present and future conditions, the conservation implications of which are discussed. As species conservation requires knowledge of how recreational pressure is distributed throughout a site, a novel methodology was developed using Thetford Forest as a case study. GIS-based Network Analysis was combined with statistical modelling to predict the number of disturbance events from recreationists for all path sections throughout the site. This tool was able to test the consequences of altering site access on the number of hypothetical new woodlark territories likely to become occupied. This study contributes to a relatively small body of work on the importance of biodiversity for recreation and provides novel spatial approaches for quantifying demand and testing conservation interventions

Impact of Neurofibromatosis 2 on Quality of Life

Objectives: To perform a case note review to describe unusual clinical manifestations of NF2 within the patient cohort. To describe quality of life (QOL) in individuals with Neurofibromatosis 2 (NF2) using qualitative and quantitative measures. To develop a reliable, validated disease-specific score to measure QOL in NF2. / Design: A case note review of 61 patients with NF2 was performed to identify trends or novel findings. The novel finding of hypertension in the cohort was investigated using a retrospective cohort study. The causes of epilepsy in NF2 were explored using imaging and histological findings. Qualitative interviews and a focus group session generated items for a pilot questionnaire. This was tested and refined. The final version (NFTI-QOL) was validated with two generic QOL questionnaires and the use of two control groups. / Results: Trends in cause of death and surgical intervention were described. In the hypertension study, 50 patients with NF2 were matched against 45 controls. Mean systolic and diastolic blood pressure (BP) was significantly higher in the NF2 group than the control group (p=0.003). Imaging of 5 individuals with epilepsy and NF2 was reviewed and cortical lesions were identified in all cases. NF2 impacts QOL in a number of areas, and these are described using framework analysis and quantitative measures. An 8-point disease-specific QOL score for NF2 patients was developed with good internal reliability. It correlated strongly with clinician rated disease severity in NF2, with stronger correlation than the Short-form 36 (SF-36) in this regard, and was validated against both SF-36 and EuroQOL. / Conclusions: The primary aim of this project was to produce a disease-specific QOL score for NF2 and this has been achieved. There was a novel finding of hypertension in NF2, and if this is confirmed with a prospective study, it may lead to changes in assessment and management

Principles of South African prison law and proposals for their implementation

There are two broad areas of prisoner rights law that require development. The first area is that of the development of a common law framework with which to analyse disputes regarding the rights of prisoners. The second relates to the significant tension that exists between the conditions of detention that the Correctional Services Act envisages and the actual conditions of detention in South Africa prisons. This second aspect requires that a mechanism be created for the meaningful exercise of rights by prisoners. As a precursor to both of the above discussions it is necessary to understand the history of prisons and the intentions of those who designed this form of punishment. As will be illustrated there tends to be to-and-fro shift in intention on the part of the authorities between those who intend imprisonment as a humane form of punishment which seeks to reform the offender and the subsequent despair of that project of reformation with a resultant focus on security and mere detention of the offender. It is also a history of conditions of detention that are generally inhumane. These poor conditions are sometimes caused by neglect on the part of the authorities but ofttimes caused by the belief that harsh conditions of detention are a deterrent to wouldbe offenders. The advent of human rights law has placed an increasingly more onerous responsibility on the state to care for the well-being of prisoners whilst in custody. This duty includes, but is not limited to, the duty to care for the prisoner’s mental and physical health, ensure that they are safe from physical violence both from fellow prisoners and staff as well as a duty to ensure that they receive the necessities of life. Various failures by the state have led to increased litigation against the state. This will continue to create an ever increasing burden on the state as the number of long term prisoners increase and damages awards are made by the courts, in favour of prisoners, against the state for various reasons. These reasons include diseases contracted by prisoners whilst in custody and constitutional damages following death in custody. It is therefore necessary to develop a clear framework with which to analyse such disputes so that decisions are made which are consistent with the principles of South African law. It is this framework which this study seeks to develop. In order to do this the relevant principles of both international prison law as well as South African law will be drawn upon. In this regard the importance of the purposes of punishment will be emphasized when engaging upon an analysis of the limitations of the rights of a person in the context of prison law. Secondly, even though a sound framework may be developed with which to analyse prisoner rights there is still the difficulty of putting a system into operation which provides a mechanism through which prisoners can exercise those rights in a meaningful way. In order to create such a system there must be recognition of the impact of criminogenic conditions of imprisonment, the purposes of punishment and the values of the South African constitution. In this regard the principles of reductionism and restorative justice are considered. Furthermore, the role of special masters will be debated and amendments to the existing legislation will be proposed

Rho Family GTPases and Rho GEFs in Glucose Homeostasis.

Dysregulation of glucose homeostasis leading to metabolic syndrome and type 2 diabetes is the cause of an increasing world health crisis. New intriguing roles have emerged for Rho family GTPases and their Rho guanine nucleotide exchange factor (GEF) activators in the regulation of glucose homeostasis. This review summates the current knowledge, focusing in particular on the roles of Rho GEFs in the processes of glucose-stimulated insulin secretion by pancreatic β cells and insulin-stimulated glucose uptake into skeletal muscle and adipose tissues. We discuss the ten Rho GEFs that are known so far to regulate glucose homeostasis, nine of which are in mammals, and one is in yeast. Among the mammalian Rho GEFs, P-Rex1, Vav2, Vav3, Tiam1, Kalirin and Plekhg4 were shown to mediate the insulin-stimulated translocation of the glucose transporter GLUT4 to the plasma membrane and/or insulin-stimulated glucose uptake in skeletal muscle or adipose tissue. The Rho GEFs P-Rex1, Vav2, Tiam1 and β-PIX were found to control the glucose-stimulated release of insulin by pancreatic β cells. In vivo studies demonstrated the involvement of the Rho GEFs P-Rex2, Vav2, Vav3 and PDZ-RhoGEF in glucose tolerance and/or insulin sensitivity, with deletion of these GEFs either contributing to the development of metabolic syndrome or protecting from it. This research is in its infancy. Considering that over 80 Rho GEFs exist, it is likely that future research will identify more roles for Rho GEFs in glucose homeostasis

The development of the spiral ganglion in the human foetus

The development of the spiral ganglion was studied in steps sections of 81 human temporal bones. By the 8th week, the spiral ganglion has already separated from the vestibular ganglion. At 13 weeks two distinct populations are observed that correspond to neuron and Schwann cells. At 15 weeks the spiral ganglion has increased its distance from the cochlear duct and is surrounded by mesenchyme near the scala tympani. At 14 weeks a gradual decrease in the nucleus-to-cell area ratio was observed in spiral ganglion neurons that may reflect a morphological adaptation to function. By the 23rd week the modiolus begins to ossify and the spiral ganglion is surrounded by bony trabeculae. The time course of spiral ganglion development follows that of the stria vascularis and organ of Corti, although maturation changes are still observed in the neuronal population even beyond 20 weeks

Court Supervised Institutional Transformation in South Africa

The traditional adversarial model of litigation in South Africa operates on the basis that two or more parties approach the court, each with its own desired outcome. The court is then obliged to decide in favour of one of the parties. A different model of litigation is emerging in South African law. This model involves actions against public institutions that are failing to comply with their constitutional mandate. In this type of litigation there is seldom a dispute regarding the eventual outcome that is desired. Both the applicant and the state, in its capacity of the respondent, have a broad consensus about the manner in which the institution should operate or be transformed. There is accordingly agreement regarding the eventual outcome and the shortcomings that should be addressed. The primary issue relates to the details of the implementation of the transformation of the institution in question, in order that the constitutional mandate of the institution in question will be met. An example of this form of litigation can be seen in litigation concerning the conditions in which prisoners are detained in South African prisons. The constitutional mandate for the imprisonment of offenders is contained in the Correctional Services Act. Ongoing human rights violations often take place in prisons. These include staff shortages, shortages of medical staff and facilities, prison overcrowding, inadequate staff development, the prevalence of HIV/AIDS, infrastructure defects and maintenance problems, gangsterism, requests for prisoner transfers and problems associated therewith, the ineffectiveness of parole boards, staff development needs that are not addressed, an excessive focus on security, lack of rehabilitation and vocational training programmes and assaults of prisoners. The courts have on occasion issued a structured interdict as an appropriate remedy. However, problems arise when violations are widespread and no single order can cause the problems to be properly addressed or where the executive fails to implement or even ignores court orders. Thus, the wrong which is complained of is not a wrong done to a particular person, but the constitutional wrong is the manner in which the institution executes its mandate vis-a-vis the vulnerable beneficiaries of the public service in question. The transformation thereof is designed to bring the institution within its constitutional duties and bounds. There is usually no dispute about the failures of the organisation and court orders are often taken by consent. The question which arises is how it can be ensured that a public institution such as a school, welfare department, hospital for the mentally disabled, home for the elderly or prison, which is designed to serve or accommodate the vulnerable may be brought into conformity with its constitutional mandate where there are continual and persistent failures to do so. Even where court orders are obtained, there are often significant problems with the implementation thereof. In the case of prisons, a possible solution, which has been employed in the United States of America and which may be adapted for use in the South African context, is that of a post-trial special master or court appointed supervisor, who supervises the transformation of the public institution until such time as the non-compliance has been appropriately resolved. In this article the role and functions of the American special master will be set out. The feasibility of importing such an office into the South African context will be evaluated.   &nbsp