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This thesis presents a system developed to account for the observation that subverbal causation is present in stative structures, which requires a reanalysis of the subverbal primitives involved in causal structures (e. g. McCawley (1968); Dowty (1979)) where cause is not attributed eventive meaning nor restricted to combining with eventive arguments. The foundation of the system developed here is the idea that the contribution and role of any functional head should be minimal and consistent across contexts. With this in mind, I show that cause can not be attributed either the role of introducing Agent arguments, nor the role of introducing changesof- state. The first task is factored out to do, the latter to become. The contribution of cause itself is shown to be the following: i) it introduces inanimate Causers, either eventive or stative in its specifier, ii) it introduces the result in its complement, either directly as in statives, or by embedding another event, usually a change-of-state associated with become, iii) when its specifier is unfilled, which can only be the case when the subject of the sentence is an Agent, an implicit event argument is inserted in the unrealised specifier position. Further, it is shown that the arguments of cause must be eventualities and these eventualities must be of the same ontological category: either both states or both events. This restriction cause places on its arguments is termed ontological harmony. Although developed to account for stative causation, the system presented here is shown to have a number of explanatory consequences. The conclusion that eventiveness must be associated with either do or become is seen to explain alternations in entailment patterns across a number of different verb classes, including provoke-class psych verbs, causativised activity verbs and biclausal quasi-causals, a class that cuts across familiar previously defined classes. This has implications for how verbs are classified, suggesting a move away from classifying verbs on the basis of Aktionsarten, towards on the basis of their subverbal meaning primitives.

The breakdown of biological tissue during mammalian decomposition results in the production of both gases and liquids. These substances are the result of large molecules, such as proteins breaking down to create smaller compounds A large number of factors affect this process, and therefore a series of experiments are needed to be conducted to understand the complex process of the decomposition process. Much of the research in this area focusses on two avenues; detection/recovery of mammalian remains, and the development/enhancement of the methods used to determine the time since death. This project looks to combine a variety of analytical techniques, to develop methodologies that are more reliable and sensitive to better understand the chemical applications to forensic taphonomy. The aim was to conduct multi-disciplinary and multi-model experiments, to encapsulate the complex reaction mechanisms that occur during mammalian decomposition. The impact of extraneous variables is a commonly identified aspect within the literature, and prevents the correlation to any real understanding of what occurs during the decomposition process. As a result, laboratory controlled experiments with varying artificial environments (aerobic/anaerobic/aerobic buried) were undertaken to explore the fundamental biochemical breakdown of biological tissue. Single organ and whole mammal decomposition studies were conducted, to identify the variation of between the various tissue types. Field experiment were also conducted to look at how impactful the extraneous variables had on the process of decomposition and to highlight any similarities or differences Various analytical techniques were used to analyse a wide range of analytes, however the analysis of volatile organic compounds (VOCs) was the main focus of the research. The analysis of the medium surrounding the whole mammal was also analysed towards the later stages of the research, looking at the soil VOCs, anionic content and response by cadaver dogs.

It has been established that plant diversity affects ecosystem functioning by controlling nutrient and C cycling. However, little is known about the effect of plant diversity on belowground processes such as root turnover and root decomposition, and the effects that diversity loss could have on C cycling. Thus, this PhD thesis focused on disentangling how plant diversity and plant identity affect two important mechanisms: root turnover and root litter decomposition. The overall hypotheses were: i) fast-growing species characterized by high quality roots have faster turnover and decomposition, compared with slow-growing species, ii) Plant communities with higher diversity have higher root litter decomposition and root turnover because of complementary effects and iii) high root turnover rates are linked to higher ecosystem C uptake rates. A set of two glasshouse-based experiments focusing on root turnover and root litter decomposition were performed using two fast-growing species and two slow-growing species were grown as monocultures and mixtures. Finally, using a 20-year long-term field experiment the effect of plant diversity on root turnover was assessed. The findings show that root decomposition and turnover follow the 'root economic spectrum' but neither root turnover nor root litter decomposition was correlated with plant growth strategy. Diverse communities had higher root turnover than monocultures while root litter decomposition was slower suggesting that root quality varied between living and dried dead roots. Surprisingly, high root turnover rates were not linked to high ecosystem C uptake rates while root traits reflecting higher C investment and high nitrogen were strongly correlated with higher net ecosystem exchange. Overall, the results presented in this thesis show the complexity of belowground interactions and the need for further studies with a higher species spectrum that helps to understand the underlying mechanism of these interactions.

Generating automatically a hexahedral mesh for a 3D domain of arbitrary complexity is a challenging problem that has puzzled the research community considerably. As opposed to tetrahedral mesh generation, there is no existing algorithm that can operate with the push of a button and produce the result that the analyst is expecting. Most of the times manual intervention is required. Due to this fact, generating a hexahedral mesh is often the most time-consuming step of a simulation. More precisely, in many cases analysts manually decompose the domain into blocks and then use existing methods to generate a hexahedral mesh in each of these regions separately. However, decomposing even a simple model into blocks is not an easy task and requires a lot of experience and skills. During the last decade a lot of focus has been given in trying to understand the underlying structure of a block decomposition in an attempt to automate this process. It has been observed that, some critical lines of the decomposition where other than four blocks join (called singularity lines) are of high importance. This has motivated many researchers to develop methods that first identify these lines and then, based on them, generate the decomposition of the domain. However, even for simple models these methods often fail to identify all the necessary singularity lines and, as a result, a block decomposition cannot be created. In this thesis, a novel approach of generating singularity lines and using them to generate block decompositions of 3퐷 domains is presented. As opposed to existing algorithms that rely on a tetrahedral mesh that discretizes the domain, here the medial object (or medial axis) of the domain is used. The key contributions of the work can be summarised into the following three. 1) A method that utilises the structure of the medial object and the directional information of its touching vectors to generate a novel direction field that consists of frames on medial vertices and medial edges and cross-fields on medial surfaces is presented. 2) A method that utilises this direction field to construct singularity lines on the interior of the domain (as far as possible from the boundary) and a set of streamlines emanating from them (that represent partition surfaces) is presented. 3) A method that utilises the proximity information that is encapsulated by the medial object to extend singularity lines, streamlines and concave features of the domain into a set of partition surfaces that divide the domain into block regions is presented. Furthermore, the proximity information that is encapsulated by the medial object provides additional information that proves useful to understand the reason the singularity lines appear on the interior of the domain. Based on that, limitations are presented and suggestions are proposed on possible paths of research to tackle them. By making the connection between the medial object of the domain and singularity lines, a new step is performed in the way to generating a method that can automatically create a hexahedral mesh for an arbitrary model. At the current stage, the method is presented for models of simple or moderate complexity that are useful to experiment and provide a framework to investigate and extend the capabilities of the method. In order for the method to be able to analyse industrial models of high complexity further development and research is required.

This dissertation addresses the question of how plant species shifts would impact carbon cycling in ecosystems, which are likely to soon and strongly be affected by climate change. Examples of such ecosystems are the high latitudes and the high altitudes, where the treeline ecotone can be an early indicator of changes in plant community composition. Biotic changes aboveground also modify belowground processes, particularly carbon (C) and nutrient cycling between plant roots and the assembled microbes. Plant-soil-microbe interactions were therefore studied across treelines in the Peruvian Andes and sub-arctic Sweden. The first objective was to determine and compare the present soil C and nitrogen (N) stocks and vegetation characteristics through systematic study of a high altitudinal tropical and a sub-arctic treeline. This revealed higher soil C-stocks in the boreal region with potentially also higher microbial activity in summer. For both countries, organic soils were higher in C and N contents compared to the mineral soils. Soils were sampled from both soil horizons across respective treelines and taken to the laboratory to deepen the question of functionality. Microbial mineralisation of soil organic matter (SOM) was quantified in a microcosm soil incubation with addition of substrates of different C:N ratios. Treatment C:N had negligible effect on SOM-mineralisation, which was reduced following substrate addition in the majority of incubations (negative priming). Mechanistically, this questions the N-mining hypothesis and suggests preferential substrate use. For the final data chapter, efforts were made to bring together all three compartments of soils, plants and microbes in vivo and study how their interactions mediate carbon and nutrient cycling between them. Negative rhizosphere priming was measured in most soils during the course of the late growing season. This consistent result provides new insights to potential mechanisms of the finely tuned synchronisation of plant-soil-microbe interactions. In the final discussion, these results were set into context to anticipate what could be done to further our understanding of ecosystem functioning at appropriate scales. Unravelling the interactions of plants, soils and microbes in more detail could help resolve the mechanisms of nutrient cycling and energy flows in different ecosystems and estimate the impact of climate change on the global carbon cycle with less uncertainty.

A forecast for an event should be based on a probability distribution of the possible outcomes of the event. In assessing the forecast, the forecast is given a penalty according to the outcome that occurs. The penalty, or score, is determined by a scoring rule and proper scoring rules are preferred; under a proper scoring rule, there is no incentive for a forecaster to issue a forecast that differs from the forecast they believe is appropriate. For proper scoring rules, the accuracy of a forecaster is defined to be their expected score over all possible forecasts and outcomes. Other measures of forecaster performance can be obtained by expressing accuracy as a sum of several terms, a process known as decomposing the accuracy. Each term of a decomposition measures a quality of the issued forecasts; qualities considered important are those that represent features of the joint distribution of the forecasts and outcomes. In the main decomposition, which we call the URR decomposition, the terms are uncertainty, resolution and reliability. The form of the URR decomposition is known for scoring rules of discrete events and their precise-probabilistic forecasts, which are forecasts issued as precisely-known probability distributions. We extend this URR decomposition to events with outcomes in any space and forecasts that may be functions of a probability distribution. We also determine in general form a second decomposition of accuracy, the RDC decomposition, in which the terms refer to the qualities of refinement, discrimination and correctness of the forecasts; the RDC decomposition has previously only be calculated in the specific instance of a binary event under the Brier scoring rule (Brier, 1950). The URR and RDC decompositions must be modified if the issued forecasts or recorded outcomes are separated into groups or bins before being assessed, and we give these amended decompositions. In a different setting, the URR and RDC decompositions we derive can also be used to examine the properties of interval-probabilistic forecasts. Interval-probabilistic forecasts are specific to binary events and issue a range of probabilities that the event will occur. There is little previous work on interval-probabilistic forecasts and to apply the URR and RDC decompositions we first define and characterise proper scoring rules for interval-probabilistic forecasts, known as interval-proper scoring rules, before establishing the URR and RDC decompositions of a particular interval-proper scoring rule, the interval-Brier scoring rule.

The tundra is currently warming twice as rapidly as the rest of planet Earth, which is thought to be leading to widespread vegetation change. Understanding the drivers, patterns, and impacts of vegetation change will be critical to predicting the future state of tundra ecosystems and estimating potential feedbacks to the global climate system. In this thesis, I used plant traits - the characteristics of individuals and species - to investigate the fundamental structure of tundra plant communities and to link vegetation change to decomposition across the tundra biome. Plant traits are increasingly used to predict how communities will respond to environmental change. However, existing global trait relationships have largely been formulated using data from tropical and temperature environments. It is thus unknown whether these trait relationships extend to the cold extremes of the tundra biome. Furthermore, it is unclear whether approaches that simplify trait variation, such as the categorization of species into functional groups, capture variation across multiple traits. Using the Tundra Trait Team database - the largest tundra trait database ever compiled - I found that tundra plants revealed remarkable consistency in the range of resource acquisition traits, but not size traits, compared to global trait distributions, and that global trait relationships were maintained in the tundra biome. However, trait variation was largely expressed at the level of individual species, and thus the use of functional groups to describe trait variation may obscure important patterns and mechanisms of vegetation change. Secondly, plant traits are related to several key ecosystem functions, and thus offer an approach to predicting the impacts of vegetation change. Notably, understanding the links between vegetation change and decomposition is a critical research priority as high latitude ecosystems contain more than 50% of global soil carbon, and have historically formed a long-term carbon sink due to low decomposition rates and frozen soils. However, it is unclear to what extent vegetation change, and thus changes to the quality and quantity of litter inputs, drives decomposition compared to environmental controls. I used two common substrates (tea), buried at 248 sites, to quantify the relative importance of temperature, moisture and litter quality on litter decomposition across the tundra biome. I found strong linear relationships between decomposition, soil temperature and soil moisture, but found that litter quality had the greatest effect on decomposition, outweighing the effects of environment across the tundra biome. Finally, I investigated whether tundra plant communities are undergoing directional shifts in litter quality as a result of climate warming. Given the importance of litter quality for decomposition, a shift towards more or less decomposable plant litter could act as a feedback to climate change by altering decomposition rates and litter carbon storage. I combined a litter decomposition experiment with tundra plant trait data and three decades of biome-wide vegetation monitoring to quantify change in community decomposability over space, over time and with warming. I found that community decomposability increased with temperature and soil moisture over biogeographic gradients. However, I found no significant change in decomposability over time, primarily due to low species turnover, which drives the majority of trait differences among sites. Together, my thesis findings indicate that the incorporation of plant trait data into ecological analyses can improve our understanding of tundra vegetation change. Firstly, trait-based approaches capture variation in plant responses to environmental change, and enable prediction of vegetation change and ecosystem function at large scales and under future growing conditions. Secondly, my findings offer insight into the potential direction, rate and magnitude of vegetation change, indicating that despite rapid shifts in some traits, the majority of community-level trait change will be dependent upon the slower processes of migration and species turnover. Finally, my findings demonstrate that the impact of warming on both tundra vegetation change and ecosystem processes will be strongly mediated by soil moisture and trait differences among vegetation communities. Overall, my thesis demonstrates that the use of plant traits can improve climate change predictions for the tundra biome, and informs the fundamental rules that determine plant community structure and change at the global scale.

Humic substances (HS) are described as a complex mixture of organic molecules formed by incomplete decomposition of plant, animal and microbial matter. They are found in soil, water and air and have many environmental roles, e.g. water retention and metal ion binding in soil. Despite their importance, the molecular composition of HS is poorly understood. This is mostly because of an inability to separate individual molecules from these complex mixtures and then characterise them by standard analytical methods such as NMR and MS. In order improve the understanding of these important mixtures I have studied them using a high-resolution analytical method, Fourier transform ion-cyclotron resonance mass spectrometry (FTICR MS). Initial efforts focussed on testing the, fast, automated data analysis of the large data sets produced. Two pieces of software were compared and the reliability of the formulae assigned by these was critically evaluated. This confident formula assignment was then applied to study the consequences of different ionisation and instrumental parameters on the mass spectra obtained. The use of laser desorption/ionisation (LDI) without the need to employ a matrix required in matrix assisted laser desorption/ionisation (MALDI) was explored. A comparison of LDI and electrospray ionisation (ESI) FTICR MS of natural organic matter samples showed that these methods ionise complementary sets of compounds. The LDI ionised compounds were characterised as aromatics or condensed aromatics and compounds belonging to lower oxygen classes (maximum number at O8), while ESI ionised higher oxygen classes (maximum number at O16) with a vast majority of compounds classified as aliphatic based on their modified aromaticity index. MALDI and LDI spectra produced very similar data with over 90% matching formulas implying that fragmentation is not caused by LDI, as taught previously. My work showed that to maximize the coverage by FTICR MS of the molecular space occupied by these complex mixtures, multiple ionization methods must be used. As a particularly convenient and readily deployable ionization technique, LDI should be included in standard analytical protocols for FTICR MS analysis of NOM. I have explored different parameters and experimental settings to obtain a fuller coverage of the molecular space of NOM, this showed that different experimental conditions enhance peak intensities in different m/z regions of the FTICR MS spectra and that information can be obtained outside of the narrow 200-700 m/z window. To gain chemical and structural information about humic substances beyond what is currently known, experiments aimed to label HS using different isotopes and at specific sites were developed and tested. Two methylation reactions were of particular interest. A methylation that selectively targeted carboxylic acid groups and incorporated deuterium in the form of CD3 groups. An international standard, Suwannee River fulvic acid, was methylated and analysed by high-resolution mass spectrometry in order to gain information on the number and distribution carboxylic acid groups. This proved challenging due to the reactivity of the unknown molecules being difficult to determine in advance. Additionally, the peak separation being reduced to as low as 1.5 mDa pushed the instrument resolution and assignment confidence to their limits. The second methylation method explored used 13CH3I, a nonselective agent reacting with any labile proton, particularly attaching 13CH3 groups to carboxylic, phenolic and alcoholic OH groups. I prepared a methylated sample of fulvic acid from a Red Moss raised bog (Balerno, near Edinburgh) ready for analyses by high field NMR. This investigation yielded structures of a number of phenolic compounds for the first time by NMR.

Land use change is a major driver of species loss worldwide, the extent and intensity of agricultural land use poses particular pressures for biodiversity and the ecosystem services it provides. In recent years, agroecosystems have seen the introduction of 2nd generation bioenergy crops in order to tackle anthropogenic climate change, providing a renewable alternative to fossil fuels. In this thesis I study the impact of cultivating two commercial perennial energy crops (PECs), Miscanthus x giganteus and willow short-rotation coppice, when compared to the cereal crops they replace. I investigate processes relevant to the provisioning of pollination and decomposition services and explore patterns of soil element bioaccessibility alongside analyses of the similarity and diversity of soil bacterial communities. When compared to cereals, I find a consistent increase in pollinator (hoverfly, bumblebee and butterfly/moth) wildflower visitation in the margins of willow but not Miscanthus. In Miscanthus, opposing trends arose for different pollinator taxa: butterflies/moths were more frequent flower visitors in Miscanthus margins than cereal margins, while hoverfly flower visits were most frequent in cereal margins. Furthermore, the availability of margin wildflowers was enhanced in willow but not Miscanthus and the seed set of margin phytometers was similar between Miscanthus and cereals. Cultivation of willow, in particular, may therefore yield local conservation benefits for both wildflowers and pollinators. However, there was no evidence for enhancement of pollinator activity in cereals adjacent to either PEC, indicating that the strategic cultivation of these crops is unlikely to enhance pollinator service provision in the wider agri-environment. For investigated soil elements, bioaccessibility in PECs did not differ significantly to cereal controls, and denaturing gradient gel electrophoresis (DGGE) revealed no difference in the diversity of bacterial communities. Similarly, DGGE fingerprint patterns did not indicate the development of crop specific assemblages, demonstrating that the mobility of soil elements and structure of bacterial communities were principally determined by factors other than the identity of the crop cultivated. Investigation of meso-microfaunal decomposition rates in Miscanthus using litter bags demonstrated an impact on decomposition processes, with a significant increase in winter decomposition rates in the PEC when compared to cereals.

Tropical soils are a globally important store of terrestrial carbon (C) and source of atmospheric carbon dioxide (CO2), regulated by the activity of soil microorganisms, through the mineralisation of plant residues and soil organic matter (SOM). Climatic warming will influence microbial activity, and this may accelerate the rate of C release from soils as CO2, contributing to alterations in current atmospheric composition, and generating feedbacks to climate change. Yet the magnitude of C loss from tropical soils remains uncertain, partly because we do not fully understand how non-climatic factors – including the chemistry of plant inputs, the availability of soil nutrients and the composition of the decomposer community – will interact to determine the response to changes in temperature. This thesis examines how these factors together regulate the rate of C cycling in contrasting soils across a 3400 m tropical elevation gradient in the Peruvian Andes, spanning a 20 ºC range (6.5 – 26.4 ºC) in mean annual temperature. Large-scale field-based manipulation experiments, translocating leaves and soil-cores across the elevation gradient (to impose an in-situ experimental warming treatment), were combined with controlled laboratory studies to examine the microbial-scale mechanisms which underlie the processes of decomposition and soil respiration observed in-situ. Results show that, across the gradient, rates of leaf-decomposition were determined principally by temperature and foliar chemical traits, while soil fertility had no significant influence. The effect of temperature was, however, stronger across higher-elevation sites, suggesting a greater vulnerability of the C-rich soils in montane systems to increased C loss under climatic warming. In lowland forests, the presence of invertebrate macrofauna also accelerated rates of decomposition, but leaf chemistry explained the greatest proportion of the observed variance, with a strong role for leaf chemical traits also identified under controlled conditions. Despite marked differences in microbial abundance and community composition among soils, these metrics were not associated with observed rates of decomposition. These results suggest that climate-related changes to plant species distributions (with associated changes to the chemistry of leaf-inputs), and upslope extension of macrofaunal ranges, could strongly influence future rates of leaf decomposition, independently of the direct response to warming. From the soil translocation study, root-soil interactions stimulated substantial net C loss from montane soils following translocation downslope (experimental warming treatment), indicating that warming-related changes to root productivity, exudation and/or species-composition could represent an important mode of future C loss from these soils. To examine more closely how inputs of plant-derived C influence the turnover of pre-existing SOM, and whether soil nutrient availability modulates the response, soils were amended with simple and complex 13C-labelled substrates in combination with inorganic nutrient treatments. Isotopic partitioning was used to determine the degree to which C and nutrient inputs accelerated (positive priming) or retarded (negative priming) the decomposition of SOM. Amendment of upper montane forest and montane grassland soils with nitrogen (N; alone and in combination with C) substantially retarded the decomposition of SOM, suggesting that microbial demand for N strongly regulates the turnover of organic matter in these soils. In contrast, amendment of lower montane and lowland forest soils with C stimulated positive priming of SOM, which was strongest in response to the simple C substrate and was not influenced by nutrient treatments, suggesting that microorganisms in these soils are primarily constrained by availability of labile C. Functional differences among microbial groups were also evident, with gram-negative bacteria and fungi using more labile sources of C while gram-positive bacteria used more complex C. Together, results from these studies considerably advance our understanding of soil C dynamics across lowland and montane systems, painting a rich picture of interacting processes which will determine the future soil C balance in tropical ecosystems. They show that the influence of temperature on the rate of soil C cycling is strongly affected by the nature and composition of plant-derived and atmospheric inputs, the principal additional constraints varying with elevation, leading to both opposing and reinforcing effects on rates of decomposition. The greater observed temperature sensitivity of decomposition at higher elevations is coupled with high microbial demand for N which regulates the turnover of SOM, whereas at lower elevations leaf decomposition is accelerated by active macrofaunal breakdown, while microbial decomposition of SOM is constrained by the availability of labile C. Under a global change scenario of increased temperature and N deposition, results therefore suggest that: (i) modified chemistry of plant inputs will influence rates of decomposition, independently of climate; (ii) increased availability of labile C will lead to more rapid decomposition of SOM at lower elevations; (iii) greater root productivity (associated with warming and plant-community shifts) will stimulate soil C loss across montane regions; but (iv) at higher elevations, a possible countervailing effect may be imposed on rapid warming-accelerated decomposition if increased N availability reduces microbial mineralisation of SOM. The net effect on the ecosystem C budget will depend on the balance of C gain from primary productivity and C loss from soils. Overall, however, the results presented here suggest that the large soil C stores in higher-elevation montane regions are particularly vulnerable to substantial reductions under exposure to short- and medium-term climatic warming.

Ba0.5Sr0.5Co0.8Fe0.2O3-delta (BSCF) and SrCo0.48Fe0.12Ti0.4O3-delta (SCFT) were synthesised by co-precipitation. BSCF was pressed and sintered at 1100℃ for 10 hours to pellets (relative density: 93%) from which X-ray diffraction (XRD) revealed single Pm-3m phase (a=3.9782 A). Scanning electron microscopy (SEM) revealed clear equiaxed grains (grain size 33 ± 16 micro metre). The pellets were decomposed in 7 ± 1 % CO2/N2 at 800℃ for 1 to 30 minutes. XRD confirmed secondary phases: R-3mH phase (a=b=5.1397 A, c=9.4847 A) and Fm-3m phase (a=4.2490 A). Electron backscattered diffraction (EBSD) ascribed R-3mH and Fm-3m phases to the surface and part of the cross-section precipitates, respectively as revealed by SEM. Energy dispersive X-ray spectroscopy (EDX) revealed the compositions of R-3mH and Fm-3m phases to be Ba0.65±0.03Sr0.35±0.03CO3 (BSC) and CoO, respectively. Transmission electron microscopy (TEM) and EDX revealed the structure (15R, R3m and R-3mH) and composition (Ba0.20Sr0.10Co0.59Fe0.10Ox) of lamellar precipitates in cross-section, suggesting Ba and Sr diffuse from the lamellae to BSC. A unique orientation relation (BSCF {111} // BSC {0001}) was uncovered by EBSD. TEM revealed high symmetry contact planes of lamellae and BSCF, suggesting nucleation energy governs decomposition. Fresh BSCF pellets were decomposed in N2 at 800℃. Fm-3m and P63/mmc phases were confirmed by XRD and lamellae were observed by SEM, followed by decomposition in 7±1 % N2/CO2 at 800℃. XRD revealed higher weight % of BSC and CoO. SEM revealed BSC preferring lamellae, hence hexagonal phases accelerated BSC formation. BSCF pellets were dip coated in SCFT propan-2-ol suspension (3:10), followed by sintering at 1165℃ for 10 hours. XRD revealed a Pm-3m phase (a=3.885 A) and SEM revealed a grain size of 65 ± 9 micro metre and open porosity of 1.6 ± 1 %. They were annealed in 7 ± 1 % CO2/N2 at 800℃. XRD revealed no secondary phases, suggesting enhanced stability. However, oxygen permeability was reduced (1.2 ml/cm2 to 0.8 ml/cm2) because the coating composition changed to Ba0.20Sr0.27Co0.40Fe0.10Ti0.04Ox; this was revealed by EDX.

The inclusion of lime in burials is observed in historical and archaeological records, in contemporary mass graves and forensic cases. Clearly there are controversies within the literature and there is a general misconception of the effects of lime on decomposition. Recent casework in Belgium and the UK involving the search for human remains buried with lime, have demonstrated the need for a more detailed understanding of the effect of different types of lime on cadaver decomposition and its micro-environment. Field and laboratory experiments using pigs as human body analogues were undertaken to obtain a better understanding of the taphonomic processes that govern lime burials. The changes observed in the experiments were related back to archaeological parallels in which white residues have been found. The combined results of these studies demonstrate that despite conflicting evidence in the literature, hydrated lime and quicklime both delay the initial stages of the decay process but do not arrest it completely. The end result is ultimately the same: skeletonisation. Furthermore this study stresses the importance of the specific microenvironment in taphonomic research and highlights the need for chemical analysis of white residues when encountered in a burial. Not all white powder is lime. White residue could be identified as calcium carbonate, building material, body decomposition products, minerals or degraded lead. This study has implications for the investigation of clandestine burials and for a better understanding of archaeological plaster burials. Knowledge of the effects of lime on decomposition processes also have bearing on practices involving the disposal of animal carcasses and potentially the management of mass graves and mass disasters by humanitarian organisation and DVI teams.

Macromolecular structures, such as lignin and cellulose, are important components of soil organic carbon, the major terrestrial global carbon pool. The degradation of these macromolecules, including lignin and cellulose, in plant-derived soil organic matter, is important to the global carbon cycle. In grasslands, saprotrophic (decomposer) fungi are major decomposers of such organic material. Some of these compounds, such as lignin are relatively resistant to decay by the microbial community if compared with other compound classes such as cellulose. In this work we investigate the involvement of fungi in the decomposition of both lignin and cellulose and look to link the decomposition processes observed in the field to those observed in a laboratory-controlled environment. The key findings of this work are:- Field based experiments in both tropical and temperate environments indicated that lignin can be degraded completely, most likely by white-rot fungi, as shown by the shifts in the [Ac/Al]S, [Ac/Al]G and [S/G] relative lignin decomposition state proxies. The results confirm that even in a very low carbon environment, fungi are able to completely degrade lignin over time. However, lignin is degraded much faster in tropical environments. Culturing experiments showed that it was possible to isolate a number of fungi present on the degraded wheat straw collected in the field, especially soft-rot fungi. When used in microcosm experiments using a range of organic substrates, the relative lignin decomposition state proxies indicated that Absidia cylindrospora and Trichoderma koningii are not able to completely degrade lignin but preferentially degrade cellulose. Cellulose degradation rates are much higher than those of lignin in degraded field samples over time, confirming previous work.

Moderation does not constitute a monolithic model and the difference in the moderation process will influence the way a political party manages its internal dynamics. The cases of the AKP and the PKS show that both have different levels of moderation due to the different contexts of their social and political environments. The AKP has to deal with an extreme interpretation of secularism in Turkey that influences the party’s members to refrain from any confrontation with secular strongholds. The PKS has more freedom to express its ideology in the Indonesian democratic political system; hence the party is able to develop internal organisational procedures and programmes based on religious principles. To anticipate difficulties arising from from moderation, the AKP uses an organisational approach to give space for open and dynamic internal management and reduce the role of ideology significantly. The PKS still utilises its ideology in managing the impact of moderation by defining religious values as principles of organisation in parallel with organisational principles. Both parties are relatively successful in convincing their members to trust the party and its leaders in different ways. Party vision and personal charisma are more apparent for the AKP, although the PKS has to rely on interpretation of ideology as the main source of trust. By placing more emphasis on organisation, the AKP employs definition of violation toward party’s rules and decisions based on an organisational approach. In contrast, the definition of violation in the PKS relies on both religious and organisational principles. As a result, the AKP implements policies to dismiss members based on unambiguous principles with relatively insignificant opposition. The PKS has to deal with complaints of dismissal since the policies are taken based on interpretation of procedures and reasons. It is also proven that the AKP is able to convince voters by offering programmes to meet popular demands without relying on a religious agenda. While the PKS has been successful in developing an effective and solid party, it still has many problems in gaining support during elections as its pragmatic adjustment moderation also generates confusion internally and externally.

This thesis describes a stochastic ship routing problem with inventory management. The problem involves finding a set of least costs routes for a fleet of ships transporting a single commodity when the demand for the commodity is uncertain. Storage at consumption and supply ports is limited and inventory levels are monitored in the model. Consumer demands are at a constant rate within each time period in the deterministic problem, and in the stochastic problem, the demand rate for a period is not known until the beginning of that period. The demand situation in each time period can be described by a scenario tree with corresponding probabilities. Several possible solution approaches for solving the problem are studied in the thesis. This problem can be formulated as a mixed integer programming (MIP) model. However solving the problem this way is very time consuming even for a deterministic problem with small problem size. In order to solve the stochastic problem, we develop a decomposition formulation and solve it using a Branch and Price framework. A master problem (set partitioning with extra inventory constraints) is built, and the subproblems, one for each ship, involve solving stochastic dynamic programming problems to generate columns for the master problem. Each column corresponds to one possible tree of schedules for one ship giving the schedule for the ship for all demand scenarios. In each branch-and-bound node, the node problem is solved by iterating between the master problem and the subproblems. Dual variables can be obtained solving the master problem and are used in the subproblems to generate the most promising columns for the master problem. Computational results are given showing that medium sized problems can be solved successfully. Several extensions to the original model are developed, including a variable speed model, a diverting model, and a model which allows ships to do extra tasks in return for a bonus. Possible solution approaches for solving the variable speed and the diverting model are presented and computational results are given.

The purpose of this thesis is to efficiently solve real life problems. We study LPs. We study an NLP and an MINLP based on what is known as the generalised pooling problem (GPP), and we study an MIP that we call the cattle mating problem. These problems are often very large or otherwise difficult to solve by direct methods, and are best solved by decomposition methods. During the thesis we introduce algorithms that exploit the structure of the problems to decompose them. We are able to solve row-linked, column-linked and general LPs efficiently by modifying the tableau simplex method, and suggest how this work could be applied to the revised simplex method. We modify an existing sequential linear programming solver that is currently used by Format International to solve GPPs, and show the modified solver takes less time and is at least as likely to find the global minimum as the old solver. We solve multifactory versions of the GPP by augmented Lagrangian decomposition, and show this is more efficient than solving the problems directly. We introduce a decomposition algorithm to solve a MINLP version of the GPP by decomposing it into NLP and ILP subproblems. This is able to solve large problems that could not be solved directly. We introduce an efficient decomposition algorithm to solve the MIP cattle mating problem, which has been adopted for use by the Irish Cattle Breeding Federation. Most of the solve methods we introduce are designed only to find local minima. However, for the multifactory version of the GPP we introduce two methods that give a good chance of finding the global minimum, both of which succeed in finding the global minimum on test problems.

Determining the postmortem interval (PMI) remains one of the most important but challenging factors to establish in a suspicious death investigation. Unfortunately, as time passes current methods lose accuracy and only allow investigators to approximate how long ago death occurred. Bodies interred in clandestine graves prove particularly challenging due to an abundance of variables that need to be taken into consideration. Due to the problems associated with determining the PMI of buried remains this study will utilise macroscopic, microscopic, molecular, chemical and microbiological analyses to systematically document the decompositional changes to human hair and porcine cartilage and bone in a burial environment. The aim was to correlate decompositional changes with time and develop new methods for estimating the PMI of remains found in this context. Whole trotters (from which the cartilage was harvested) exhibited decompositional changes including darkening of the dermis, skin slippage, liquefaction of soft tissues and complete skeletonisation. The decompositional changes to cartilage included a loss of cartilage covering articular facets, changes in colour and texture, formation of orthorhombic crystals, a change in surface pH and colonisation by bacteria. The bacteria found on the cartilage surface were in close proximity to the crystals and when cultured on a B-41 medium were found to precipitate crystals of the same morphology and chemical composition to those found on the cartilage surface. Three species of bacteria (Acinetobacter calcoaceticus, Acinetobacter iwoffii and Grimontia hollisae) were identified based on gas chromatography–mass spectrometry (GC-MS) of their fatty acids and one species (Comamonas sp.) was identified by DNA analysis. Formation of crystals on goat and cow cartilage proved that this was not a porcine specific phenomenon. Human hair exhibited a gradual degradation over time but this was dependent on the characteristics of the burial environment. Decompositional changes included colonisation by fungi, erosions to the cortical surface and formation of tunnels and breaks to the hair shaft. Two fungal species (Aspergillus fumigatus and Penicillium sp.) were identified based on DNA analysis of fungal ribosomal (rDNA) internally transcribed spacer (ITS) regions. The Penicillium sp. was linked with fungal tunnelling of hair. Bone exhibited little modification over time but changes were observed. These included a change in colour of the cortical surface, a change in colour and gradual loss of bone marrow and erosions, cracking and flaking of the cortical bone. Fungi were found to colonise both the bone marrow and bone surface. Whole piglets were buried to document the time period taken to reach skeletonisation. This data was used as a correction factor and combined with the bone results to give an overall time period for the decomposition changes observed. The results of this study suggest that the decompositional changes to cartilage could be used to determine the postmortem interval of buried remains. However, the degradation of hair and bone was too variable to be of use in this context.

The decisions taken during the aircraft conceptual design stage are of paramount importance since these commit up to eighty percent of the product life cycle costs. Thus in order to obtain a sound baseline which can then be passed on to the subsequent design phases, various studies ought to be carried out during this stage. These include trade-off analysis and multidisciplinary optimisation performed on computational processes assembled from hundreds of relatively simple mathematical models describing the underlying physics and other relevant characteristics of the aircraft. However, the growing complexity of aircraft design in recent years has prompted engineers to substitute the conventional algebraic equations with compiled software programs (referred to as models in this thesis) which still retain the mathematical models, but allow for a controlled expansion and manipulation of the computational system. This tendency has posed the research question of how to dynamically assemble and solve a system of non-linear models. In this context, the objective of the present research has been to develop methods which significantly increase the flexibility and efficiency with which the designer is able to operate on large scale computational multidisciplinary systems at the conceptual design stage. In order to achieve this objective a novel computational process modelling method has been developed for generating computational plans for a system of non-linear models. The computational process modelling was subdivided into variable flow modelling, decomposition and sequencing. A novel method named Incidence Matrix Method (IMM) was developed for variable flow modelling, which is the process of identifying the data flow between the models based on a given set of input variables. This method has the advantage of rapidly producing feasible variable flow models, for a system of models with multiple outputs. In addition, criteria were derived for choosing the optimal variable flow model which would lead to faster convergence of the system. Cont/d.

Oxidation developed from the surfaces into the cores of the microwaved particles. Metallic particles were also formed during microwave exposure. Lihir gold ore, in which gold was finely disseminated in pyrite and marcasite, was an extremely refractory gold ore. Without pretreatment, only 37-39% of the gold could be extracted with sodium cyanide. However, this was improved after the head ores or floatation concentrates were pretreated by microwave radiation. 74.581.2% of the gold was extracted from the microwave treated head ore. The hydrometallurgical pretreatment of pyrite and marcasite in a microwave field and a conventional heating environment was also investigated.I,n a nitric acid solution, pyrite and marcasite can be rapidly leached. Reaction temperature and the concentration of HNO3 had a significant influence on decomposition rate. Marcasite had a substantially higher i decomposition rate than pyrite. Microwave heating could promote the dissociation of marcasite and pyrite, compared with conventional heating. This was caused by special volumetric heating during microwave exposure that may induce local overheating or improve the interactions between the high dielectric loss minerals and the leaching solution. Kinetic investigations show that the decomposition of both the minerals in a nitric acid medium is controlled by chemical reactions on the surfaces of particles. The decomposition is a second order reaction with respect to nitric acid concentration. Less than 5- 7% of the decomposed sulphur was transformed into elemental sulphur during the leaching of both the minerals

In "decomposition/reconstruction" strategy, we can solve a complex problem by 1) decomposing the problem into simpler sub-problems, 2) solving sub-problems with simpler systems (sub-systems) and 3) combining the results of sub-systems to solve the original problem. In a classification task we may have "label complexity" which is due to high number of possible classes, "function complexity" which means the existence of complex input-output relationship, and "input complexity" which is due to requirement of a huge feature set to represent patterns. Error Correcting Output Code (ECOC) is a technique to reduce the label complexity in which a multi-class problem will be decomposed into a set of binary sub-problems, based oil the sequence of "0"s and "1"s of the columns of a decomposition (code) matrix. Then a given pattern can be assigned to the class having minimum distance to the results of sub-problems. The lack of knowledge about the relationship between distance measurement and class score (like posterior probabilities) has caused some essential shortcomings to answering questions about "source of effectiveness", "error analysis", " code selecting ", and " alternative reconstruction methods" in previous works. Proposing a theoretical framework in this thesis to specify this relationship, our main contributions in this subject are to: 1) explain the theoretical reasons for code selection conditions 2) suggest new conditions for code generation (equidistance code)which minimise reconstruction error and address a search technique for code selection 3) provide an analysis to show the effect of different kinds of error on final performance 4) suggest a novel combining method to reduce the effect of code word selection in non-optimum codes 5) suggest novel reconstruction frameworks to combine the component outputs. Some experiments on artificial and real benchmarks demonstrate significant improvement achieved in multi-class problems when simple feed forward neural networks are arranged based on suggested framework To solve the problem of function complexity we considered AdaBoost, as a technique which can be fused with ECOC to overcome its shortcoming for binary problems. And to handle the problems of huge feature sets, we have suggested a multi-net structure with local back propagation. To demonstrate these improvements on realistic problems a face recognition application is considered. Key words: decomposition/ reconstruction, reconstruction error, error correcting output codes, bias-variance decomposition.