Transdimensional inverse thermal history modeling for quantitative thermochronology

International audienceA new approach for inverse thermal history modeling is presented. The method uses Bayesian transdimensional Markov Chain Monte Carlo and allows us to specify a wide range of possible thermal history models to be considered as general prior information on time, temperature (and temperature offset for multiple samples in a vertical profile). We can also incorporate more focused geological constraints in terms of more specific priors. The Bayesian approach naturally prefers simpler thermal history models (which provide an adequate fit to the observations), and so reduces the problems associated with over interpretation of inferred thermal histories. The output of the method is a collection or ensemble of thermal histories, which quantifies the range of accepted models in terms a (posterior) probability distribution. Individual models, such as the best data fitting (maximum likelihood) model or the expected model (effectively the weighted mean from the posterior distribution) can be examined. Different data types (e.g., fission track, U-Th/He, 40Ar/39Ar) can be combined, requiring just a data-specific predictive forward model and data fit (likelihood) function. To demonstrate the main features and implementation of the approach, examples are presented using both synthetic and real data

Mediating Catholicism – Religious Identities, Polish Migrants and the Catholic Church in Ireland

This thesis investigates the experience of Polish migrants in Ireland and how, if at all, spirituality or the church figure in terms of social and spiritual support. Drawing on data from in-depth interviews with Polish migrants and clergy, participant observation and documentary materials and guided by theories of religion as resource, achieved identity, and transnational entity, I identify four major empirical findings. First, religion is not a significant factor motivating the migration of Polish migrants to Ireland and instead economic and social factors predominate. Second, there is considerable variation in migrants’ religious beliefs and practices, ranging from migrants who strongly identify with Catholicism to migrants who dis-identify with Catholic identity. Third, some Polish migrants rely on the church for various resources while others do not, depending on factors such as social networks, transnational ties and religious identity. I find that religion matters more as a marker of ethnic identity and social service resource than spirituality. In addition, the Polish chaplaincy draws on transnational resources to help some migrants maintain their religious identity and connection to Poland. Migrants, in turn, mobilise transnational networks to further support the preservation of ties to their homeland. Theoretically, this thesis gives weight to the perspective that religion and religious institutions operate transnationally, yet migrants’ relationship with religion is constantly negotiated and adapted depending on their time and context specific situations, some migrants ‘opt in or out’ of religion when ‘necessary’

Transdimensional change-point modeling as a tool to investigate uncertainty in applied geophysical inference: An example using borehole geophysical logs

International audienceRecently developed methods for inferring abrupt changes in data series enable such change points in time or space to be identified, and also allow us to estimate noise levels of the observed data. The inferred probability distributions of these parameters provide insights into the capacity of the observed data to constrain the geophysical analysis and hence the magnitudes, and likely sources, of uncertainty. We carry out a change-point analysis of sections of four borehole geophysical logs (density, neutron absorption, sonic interval time, and electrical resistivity) using transdimensional Bayesian Markov chain Monte Carlo to sample a model parameter space. The output is an ensemble of values which approximate the posterior distribution of model parameters. We compare the modeled change points, borehole log parameters, and the variance of the noise distribution of each log with the observed lithology classes down the borehole to make an appraisal of the uncertainty characteristics inherent in the data. Our two examples, one with well-defined lithology changes and one with more subtle contrasts, show quantitatively the nature of the lithology contrasts for which the geophysical borehole log data will produce a detectable response in terms of inferred change points. We highlight the different components of variation in the observed data: due to the geologic process (dominant lithology changes) that we hope to be able to infer, geologic noise due to variability within each lithology, and analytical noise due to the measurement process. This inference process will be a practical addition to the analytical tool box for borehole and other geophysical data series. It reveals the level of uncertainties in the relationships between the data and the observed lithologies and would be of great use in planning and interpreting the results of subsequent routine processing

Global variability in multi-century ground warming inferred from geothermal data

International audienceMeasurements of Earth's surface air temperatures covering the last 150 years show a pronounced warming (I. Harris et al., 2014) that is largely the result of human influence (Bindoff et al., 2013; Hegerl et al., 2019). Longer records of surface temperature are invaluable for placing the recent anthropogenically perturbed period in the broader context of Earth's pre-industrial climate variability (Neukom et al., 2019). The instrumental surface air temperature record is limited in the years before CE 1850 (Benestad et al., 2019; I. Harris et al., 2014; Morice et al., 2012) and only a few longer instrumental records are available from historical records (Brönnimann et al., 2019). For this reason temperature sensitive proxies such as tree and coral growth rings, ice-cores and lake sediments are used to reconstruct earlier climate variations (e.g.

Becoming a ‘real’ Catholic : Polish migrants and lived religiosity in the UK and Ireland

We are grateful to Andrew McKinnon (University of Aberdeen) for his insightful comments on an earlier version of this article. We would also like to thank the referees of the Journal of Contemporary Religion for their constructive and detailed comments which helped us to improve the argument further. The British portion of the research was funded by Porticus UK. The research team included Halina Grzymała-Moszczynska, Marta Trzebiatowska, Claire Wallace, Joanna Krotofil, Anna Jurek, and Marcin Lisak.Peer reviewedPostprin

The Spatial Dimension of Household Resilience : NIRSA Working Paper No.86

This working paper provides an analysis of the spatial dimensions of household resilience in Ireland. It was produced as the Irish national report for Work Package 7 within the FP7 Project, ‘RESCuE: Patterns of resilience during socio-economic crisis among households in Europe.’ This paper includes a qualitative analysis of key spatial aspects including crisis, health and well being; home; neighbourhood; and supra local scale. Health and well-being explores the impact of the crisis on the mind and body of participants, particularly men as they coped with a higher incidence of unemployment at the beginning of the recession. The theme of home reveals how participants strategised to maintain their homes and a sense of home with reduced resources as a result of the recession. To frame the exploration of socio-spatial dynamics of crisis, poverty and resilience we distinguish between the types of ‘communities’ that exist, the homogeneity of these neighbourhoods and the changes brought about from broader economic shifts. The constraining characteristics vary between urban and rural areas but similarities emerge in the everyday experiences of movement, attachment and change

The Spatial Dimension of Household Resilience : NIRSA Working Paper No.86

This working paper provides an analysis of the spatial dimensions of household resilience in Ireland. It was produced as the Irish national report for Work Package 7 within the FP7 Project, ‘RESCuE: Patterns of resilience during socio-economic crisis among households in Europe.’ This paper includes a qualitative analysis of key spatial aspects including crisis, health and well being; home; neighbourhood; and supra local scale. Health and well-being explores the impact of the crisis on the mind and body of participants, particularly men as they coped with a higher incidence of unemployment at the beginning of the recession. The theme of home reveals how participants strategised to maintain their homes and a sense of home with reduced resources as a result of the recession. To frame the exploration of socio-spatial dynamics of crisis, poverty and resilience we distinguish between the types of ‘communities’ that exist, the homogeneity of these neighbourhoods and the changes brought about from broader economic shifts. The constraining characteristics vary between urban and rural areas but similarities emerge in the everyday experiences of movement, attachment and change

Intracontinental deformation in southern Africa during the late Cretaceous

Intracontinental deformation accommodated along major lithospheric scale shear zone systems and within associated extensional basins has been well documented within West, Central and East Africa during the Late Cretaceous. The nature of this deformation has been established by studies of the tectonic architecture of sedimentary basins preserved in this part of Africa. In southern Africa, where the post break-up history has been dominated by major erosion, little evidence for post-break-up tectonics has been preserved in the onshore geology. Here we present the results of 38 new apatite fission track analyses from the Damara region of northern Namibia and integrate these new data with our previous results that were focused on specific regions or sections only to comprehensively document the thermo-tectonic history of this region since continental break-up in the Early Cretaceous. The apatite fission track ages range from 449 ± 20 Ma to 59 ± 3 Ma, with mean confined track lengths between 14.61 ± 0.1 μm (SD 0.95 μm) to 10.83 ± 0.33 μm (SD 2.84 μm). The youngest ages (c. 80-60 Ma) yield the shortest mean track lengths, and combined with their spatial distribution, indicate major cooling during the latest Cretaceous. A simple numerical thermal model is used to demonstrate that this cooling is consistent with the combined effects of heating caused by magmatic underplating, related to the Etendeka continental flood volcanism associated with rifting and the opening of the South Atlantic, and enhanced erosion caused by major reactivation of major lithospheric structures within southern Africa during a key period of plate kinematic change that occurred in the South Atlantic and SW Indian ocean basins between 87-56 Ma. This phase of intraplate tectonism in northern Namibia, focused in discrete structurally defined zones, is coeval with similar phases elsewhere in Africa and suggests some form of trans-continental linkage between these lithospheric zones

A Bayesian partition modelling approach to resolve spatial variability in climate records from borehole temperature inversion

International audienceCollections of suitably chosen borehole profiles can be used to infer large-scale trends in ground-surface temperature (GST) histories for the past few hundred years. These reconstructions are based on a large database of carefully selected borehole temperature measurements from around the globe. Since non-climatic thermal influences are difficult to identify, representative temperature histories are derived by averaging individual reconstructions to minimize the influence of these perturbing factors. This may lead to three potentially important drawbacks: the net signal of non-climatic factors may not be zero, meaning that the average does not reflect the best estimate of past climate; the averaging over large areas restricts the useful amount of more local climate change information available; and the inversion methods used to reconstruct the past temperatures at each site must be mathematically identical and are therefore not necessarily best suited to all data sets. In this work, we avoid these issues by using a Bayesian partition model (BPM), which is computed using a trans-dimensional form of aMarkov chainMonte Carlo algorithm. This then allows the number and spatial distribution of different GST histories to be inferred from a given set of borehole data by partitioning the geographical area into discrete partitions. Profiles that are heavily influenced by non-climatic factors will be partitioned separately. Conversely, profiles with climatic information, which is consistent with neighbouring profiles, will then be inferred to lie in the same partition. The geographical extent of these partitions then leads to information on the regional extent of the climatic signal. In this study, three case studies are described using synthetic and real data. The first demonstrates that the Bayesian partition model method is able to correctly partition a suite of synthetic profiles according to the inferred GST history. In the second, more realistic case, a series of temperature profiles are calculated using surface air temperatures of a global climate model simulation. In the final case, 23 real boreholes from the United Kingdom, previously used for climatic reconstructions, are examined and the results compared with a local instrumental temperature series and the previous estimate derived from the same borehole data. The results indicate that the majority (17) of the 23 boreholes are unsuitable for climatic reconstruction purposes, at least without including other thermal processes in the forward model

Cost-effectiveness of ranibizumab in treatment of diabetic macular oedema (DME) causing visual impairment : evidence from the RESTORE trial

Background/aims To evaluate the cost-effectiveness of ranibizumab as either monotherapy or combined with laser therapy, compared with laser monotherapy, in the treatment of diabetic macular oedema (DME) causing visual impairment from a UK healthcare payer perspective. Methods A Markov model simulated long-term outcomes and costs of treating DME in one eye (BCVA <= 5 letters) based on data from the RESTORE Phase III trial. Outcomes measured in quality-adjusted life-years (QALYs) were simulated for a 15-year time horizon based on 12-month follow-up from RESTORE and published long-term data. Costs included treatment, disease monitoring, visual impairment and blindness (at 2010 price levels). Results Ranibizumab monotherapy resulted in a 0.17 QALY gain at an incremental cost of 4191 pound relative to laser monotherapy, yielding an incremental cost-effectiveness ratio (ICER) of 24 pound 028. Probabilistic sensitivity analysis showed a 64% probability of being cost-effective at a threshold of 30 pound 000 per QALY. Combined ranibizumab and laser therapy resulted in a 0.13 QALY gain at an incremental cost of 4695 pound relative to laser monotherapy (ICER 36 pound 106; 42% probability of ICER <30 pound 000). Conclusions Based on RESTORE 1-year follow-up data, ranibizumab monotherapy appears to be cost-effective relative to laser monotherapy, the current standard of care. Cost-effectiveness of combination therapy is less certain. Ongoing studies will further inform on disease progression and the need for additional ranibizumab treatment