Conversion farm case studies

This report was presented at the UK Organic Research 2002 Conference. The poster presents some preliminary findings of work in progress on case studies of farmers interested in conversion. This work is part of the EU-funded project ‘Barriers to conversion to organic farming-QLRT-1999- 31112’

Subsidence Mechanisms of Sedimentary Basins Developed over Accretionary Crust

This thesis uses forward modelling to investigate the formation of intercratonic basins upon accretionary crust. It began from the hypothesis that accretionary crust forms with a near normal thickness crust, but a thin lithosphere inherited from the terranes that compose it. After the accretion process has ceased the lithosphere stabilises and begins to cool, causing it to grow thicker and this in turn drives subsidence of the accretionary crust. A 1-D finite difference computer code was developed to model conductive heat flow through a column of cooling lithosphere and asthenosphere. To test the hypothesis, the subsidence produced by the modelling of this process was compared to the observed subsidence from backstripping numerous basins situated on accretionary crust The model produced a good fit to the subsidence in a detailed case study of two of the Palaeozoic basins in North Africa. The study was then extended to test the applicability of to accretionary crust globally. It found that while using measured values of the crust and lithospheric thickness for each region the model produced subsidence curves that matched the observed subsidence in each basin. It makes a more coherent argument for the formation of these basins that is able to explain a wider variety of features than other proposed subsidence mechanisms such as slow stretching or dynamic topography. These results suggest that such subsidence is an inherent property of accretionary crust which could influence the evolution of the continental crust over long time periods. The model was used to investigate the subsidence of the West Siberian Basin and found the subsidence patterns to be consistent with the decay of a plume head which thinned the lithosphere. This subsidence patterns indicate the plume material thinned the lithosphere over an area of 2.5 million km2 resulting in uplift before it cooled and subsided

ELECTROCOAGULATION: UNRAVELLING AND SYNTHESISING THE MECHANISMS BEHIND A WATER TREATMENT PROCESS

Electrocoagulation is an empirical (and largely heuristic) water treatment technology that has had many different applications over the last century. It has proven its viability by removing a wide range of pollutants. The approach to reactor design has been haphazard, however, with little or no reference to previous designs or underlying principles. This thesis reviewed these reactor designs, identifying key commonalities and synthesising a new design hierarchy, summarised by three main decisions: 1. Batch or continuous operation; 2. Coagulation only or coagulation plus flotation reactors, and; 3. Associated separation process if required. This design decision hierarchy thereby provides a consistent basis for future electrocoagulation reactor designs. Electrochemistry, coagulation, and flotation are identified as the key foundation sciences for electrocoagulation, and the relevant mechanisms (and their interactions) are extracted and applied in an electrocoagulation context. This innovative approach was applied to a 7 L batch electrocoagulation reactor treating clay-polluted water. Structured macroscopic experiments identified current (density), time, and mixing as the key operating parameters for electrocoagulation. A dynamic mass balance was conducted over the batch reactor, for the first time, thereby enabling the extraction of a concentration profile. For this batch system, three operating stages were then identifiable: lag, reactive, and stable stages. Each stage was systematically investigated (in contrast to the previous ad hoc approach) with reference to each of the foundation sciences and the key parameters of current and time. Electrochemical behaviour characterised both coagulant and bubble generation. Polarisation experiments were used to determine the rate-limiting step at each electrode's surface. Consequently the appropriate Tafel parameters were extracted and hence the cell potential. At low currents both electrodes (anode and cathode) operated in the charge-transfer region. As the current increased, the mechanism shifted towards the diffusion-limited region, which increased the required potential. Polarisation experiments also define the operating potential at each electrode thereby enabling aluminium's dissolution behaviour to be thermodynamically characterised on potential-pH (Pourbaix) diagrams. Active and passive regions were defined and hence the aluminium's behaviour in an aqueous environment can now be predicted for electrocoagulation. Novel and detailed solution chemistry modelling of the metastable and stable aluminium species revealed the importance of oligomer formation and their rates in electrocoagulation. In particular, formation of the positively trimeric aluminium species increased solution pH (to pH 10.6), beyond the experimentally observed operable pH of 9. Thereby signifying the importance of the formation kinetics to the trimer as the active coagulant specie in electrocoagulation. Further leading insights to the changing coagulation mechanism in electrocoagulation were possible by comparison and contrast with the conventional coagulation method of alum dosing. Initially in the lag stage, little aggregation is observed until the coagulant concentration reaches a critical level. Simultaneously, the measured zeta potential increases with coagulant addition and the isoelectric point is attained in the reactive stage. Here a sorption coagulation mechanism is postulated; probably charge neutralisation, that quickly aggregates pollutant particles forming open structured aggregates as indicated by the low fractal dimension. As time progresses, pollutant concentration decreases and aluminium addition continues hence aluminium hydroxide/oxide precipitates. The bubbles gently sweep the precipitate through the solution, resulting in coagulation by an enmeshment mechanism (sweep coagulation). Consequently compact aggregates are formed, indicating by the high fractal dimension. Flotation is an inherent aspect of the batch electrocoagulation reactor via the production of electrolytic gases. In the reactor, pollutant separation occurs in situ, either by flotation or settling. From the concentration profiles extracted, original kinetic expressions were formulated to quantify these competing removal processes. As current increases, both settling and flotation rate constants increased due to the additional coagulant generation. This faster removal was offset by a decrease in the coagulant efficiency. Consequently a trade-off exists between removal time and coagulant efficiency that can be evaluated economically. A conceptual framework of electrocoagulation is developed from the synthesis of the systematic study to enable a priori prediction. This framework creates predictability for electrocoagulation, which is innovative and original for the technology. Predictability provides insights to knowledge transfer (between batch and continuous), efficient coagulant and separation path, to name just a few examples. This predictability demystifies electrocoagulation by providing a powerful design tool for the future development of scaleable, industrial electrocoagulation water treatment design and operation process

Patterns and hierarchies of rural settlement in Nottinghamshire before 1700

This study analyses the spatial and aspatial aspects of the settlement pattern of Nottinghamshire before 1700. Two crucial problems are encountered: firstly, much of the descriptive evidence must be taken from taxation documents which do not directly refer to settlements, and secondly the foundations of the medieval settlement pattern lay in the Anglo-Scandinavian period, for which remarkably little evidence survives in Nottinghamshire. The first of these difficulties is alleviated by treating townships as functional settlements, each based on a defined territory with a system of communal agriculture. The second, however, is more intransigent. Part I begins by reconstructing the territorial structure of the county within which the settlements existed. It then analyses the Anglo-Scandinavian and Norman settlement patterns in the light of Jones' model of the multiple estate and Taylor's exemplar of the polyfocal village. Chapter Four, which is critical to the argument, reveals that throughout the period 1100-1 TOO the overall rank-size distribution remained convex-upwards. Nevertheless, individual places did change in relative importance, and there is also evidence for the appearance of an urban hierarcy. In spatial terms, the early dominance of the south-east of the county was replaced by a more even distribution of rural settlements and wealth. Part II seeks explanations for these changes by studying individual settlements and by examining certain specific factors. It reveals that it is extremely difficult to produce generalised models concerning settlement development, but that the role of individual landlords appears to have been of fundamental importance. The presence of a large monastic house and the growth of rural marketing were also significant factors stimulating settlement growth. In conclusion, there is a vital need to re-evaluate our theoretical and abstract views concerning the nature of medieval settlement, both by undertaking detailed field research and also by drawing comparisons with contemporary processes

Material culture: an inquiry into the meanings of artefacts

The main purpose of the following inquiry is to emphasise the importance of a phenomenon long neglected by the majority of the human sciences, the artefact; each one of us, no matter what age, sex or culture, is in contact with artefacts every moment of our lives yet despite this they have received scant attention. The study begins by outlining a definition of the artefact, highlighting those characteristics which, in combination, ensure its centrality to social life before, through a discussion of Popper's ideas, proceeding to see how material culture can be conceptualised as meaningful. In order to understand how meaning becomes attached to the artefact the notion of objectification will be analysed and, consequently, so shall the importance of both the type of activity and the physical nature of the materials involved in the artefact's production. Picking up on the theme of materiality this aspect of material culture will be shown to pose major problems to any interpretation of the artefact along semiological lines; language and material culture are evinced to possess fundamentally distinct characteristics which make comparisons between them far from straightforward. These differences will be analysed further, concentrating specifically on the role of context in the establishment of meaning. This leads on to the proposal that our understanding of artefacts can occur on three levels; three forms of knowledge are thus described of which a linguistically formulated type constitutes just one kind. The penultimate chapter tackles the ways in which artefacts affect us, how they are active elements in our relationships with them; therefore, a dialectical position is postulated in which both artefacts and agents take part. Finally, the study concludes by stressing some of its wider implications and suggests a few of the practical situations to which it can be applied

Barcelona Plays: A Collection of New Works by Catalan Playwrights

Barcelona’s theater has experienced a remarkable renaissance in the years since the end of the Franco dictatorship. Soon the Catalan language, suppressed for more than three decades, became a vehicle of expression for new playwrights who challenged performance groups. This collection represents outstanding Catalan playwrights from three generations.https://scholarship.richmond.edu/bookshelf/1163/thumbnail.jp

Evaluation of a recreational team game for seniors: Lifeball - a case study

The objective of this project was to assess changes in physical activity, social isolation and loneliness of Lifeball participants as a result of participation in Lifeball. Lifeball is a team game based on walking, ball passing and goal shooting. Newly enrolled Lifeball players (n = 95) aged 50 years and over were recruited from Lifeball clubs in Western Australia. Subjects completed a questionnaire on their physical activity levels and perceptions of their psychosocial health and well-being. The questionnaire was administered at baseline and after 3 months of participation in Lifeball. There was no significant change to overall physical activity levels. However, it appears Lifeball was used to replace other recreational pursuits that the subjects were involved in. There was a positive shift in variables associated with social isolation and loneliness. Lifeball provides alternative physical activity opportunities and may help reduce social isolation and loneliness

Cryptococcal immune reconstitution syndrome during steroid withdrawal treated with hydroxychloroquine

SummaryWe present a case report of cryptococcal immune reconstitution syndrome (IRS), in a non HIV infected patient, which we treated with hydroxychloroquine with successful results. We briefly review cryptococcal IRS, possible mechanisms of action of hydroxychloroquine as an immunomodulatory agent, and its potential role in management of IRS

Terminus thinning drives recent acceleration of a Greenlandic lake-terminating outlet glacier

Ice-contact proglacial lakes affect ice dynamics and the transition of glacier termini from land- to lake-terminating has been shown to cause ice flow acceleration. In recent decades, the number and size of Greenlandic ice-marginal lakes has increased, highlighting the need to further understand these lake-terminating ice-margins as their influence on ice sheet mass balance increases. Here, time series of satellite-derived observations of ice velocity, surface elevation, and terminus position were generated at a lake-terminating outlet glacier, Isortuarsuup Sermia, and the nearby land-terminating Kangaasarsuup Sermia in south-west Greenland. At Isortuarsuup Sermia, annual surface velocity at the terminus increased by a factor of 2.5 to 214 ± 4 m yr ´1 (2013–2021), with the magnitude of this acceleration declining with distance up-glacier. Meanwhile, near-terminus surface elevation changed at a rate of -2.3 ± 1.1 m yr ´1 (2012–2021). Conversely, velocity change at Kangaasarsuup Sermia was minimal, while surface elevation change was approximately half at comparable elevations (-1.2 ± 0.3 m yr ´1). We attribute these dynamic differences to thinning at Isortuarsuup Sermia and subsequent retreat from a stabilising sublacustrine moraine, and emphasise the potential of proglacial lakes to enhance future rates of mass loss from the Greenland Ice Sheet.</p

Systems biology and big data in asthma and allergy: recent discoveries and emerging challenges

Asthma is a common condition caused by immune and respiratory dysfunction, and it is often linked to allergy. A systems perspective may prove helpful in unravelling the complexity of asthma and allergy. Our aim is to give an overview of systems biology approaches used in allergy and asthma research. Specifically, we describe recent “omic”-level findings, and examine how these findings have been systematically integrated to generate further insight. Current research suggests that allergy is driven by genetic and epigenetic factors, in concert with environmental factors such as microbiome and diet, leading to early-life disturbance in immunological development and disruption of balance within key immuno-inflammatory pathways. Variation in inherited susceptibility and exposures causes heterogeneity in manifestations of asthma and other allergic diseases. Machine learning approaches are being used to explore this heterogeneity, and to probe the pathophysiological patterns or “endotypes” that correlate with subphenotypes of asthma and allergy. Mathematical models are being built based on genomic, transcriptomic, and proteomic data to predict or discriminate disease phenotypes, and to describe the biomolecular networks behind asthma. The use of systems biology in allergy and asthma research is rapidly growing, and has so far yielded fruitful results. However, the scale and multidisciplinary nature of this research means that it is accompanied by new challenges. Ultimately, it is hoped that systems medicine, with its integration of omics data into clinical practice, can pave the way to more precise, personalised and effective management of asthma.This work was supported by the National Health and Medical Research Council (NHMRC) of Australia via a postgraduate scholarship (ref. no. 1114753) to HHF Tang, research grant (1049539) to M Inouye and K Holt, and Fellowships (1061409) to K Holt and (1061435) to M Inouye. K Holt was further supported by a Senior Medical Research Fellowship from the Viertel Foundation of Australia