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Reflexivity offers a way of reconstructing an algebra from a set of invariant subspaces. It is considered as Noncommutative Spectral Synthesis in association with synthesis problems in commutative Harmonic Analysis. Large classes of algebras are reflexive, the prototypical example being von Neumann algebras. The first example in the nonselfadjoint setting was the algebra of the unilateral shift which was shown by Sarason in the 1960s. Some further examples include the influential work of Arveson on CSL algebras, the Hp Hardy algebras examined by Peligrad, tensor products with the Hardy algebras and nest algebras. The concept of reflexivity was extended by Arveson who introduced the notion of hyperreflexivity. This is a measure of the distance to an algebra in terms of the invariant subspaces. It is a stronger property than reflexivity and examples include nest algebras, the free semigroup algebra and the algebra of analytic Toeplitz operators. Here we consider these questions for the class of w*-semicrossed products, in particular, those arising from actions of the free semigroup and the free abelian semigroup. We show that they are hyperreflexive when the action is implemented by uniformly bounded row operators. Combining our results with those of Helmer, we derive that w*-semicrossed products of factors of any type are reflexive. Furthermore, we show that w*-semicrossed products of automorphic actions on maximal abelian selfadjoint algebras are reflexive. In each case it is also proved that the w*-semicrossed products have the bicommutant property if and only if the initial algebra of the dynamics does also. In addition we are interested in classifying the commuting endomorphisms of B(H) as an important example of dynamics implemented by a Cuntz family. Recall that On does not have a nice representation space in the sense that there is no countable collection of Borel functions that distinguish the unitary invariants. Therefore we focus our attention on the free atomic representations, which Davidson and Pitts classified up to unitary equivalence. Specifically we give a necessary and sufficient condition for an automorphism of B(H) to commute with a cyclic endomorphism.

Parrotfish are a diverse and ubiquitous group found on coral reefs worldwide. They are categorised into three main feeding modes; the browsers, scrapers and excavators, which together perform a number of important functional roles on coral reefs. Scraper and excavator parrotfish are common on most Indo-Pacific coral reefs where their roles in bioerosion, sediment production, grazing pressure and sediment reworking have been shown to influence benthic community composition, reef growth potential and sediment supply to reef habitats and reef associated sedimentary landforms. However, despite the widely known importance of parrotfish on coral reefs, our understanding of how their roles in carbonate cycling vary among species and among whole parrotfish communities in different reef habitats remains limited. This thesis produces original contributions to knowledge in the areas of species specific bioerosion estimates for the central Indian Ocean, bottom-up controls of habitat type on parrotfish assemblages and how variations in parrotfish assemblages translate to contributions to carbonate cycling processes among different reef habitats. The study was carried out across eight habitats on an atoll-edge reef platform in the central Maldives, where it was found that parrotfish community composition was driven by reef structural complexity and substrate type. Parrotfish occurred in six of the eight habitats, comprising ~44% of the platform area. Among these habitats, overall grazing pressure, bioerosion rates, sediment reworking and sediment production varied markedly. These processes were also found to have different spatial patterns over the reef platform, showing that they are not necessarily tightly coupled. In addition, reef habitats can vary in their importance for both sediment supply, and the relative importance of reworked sediment. Parrotfish produced a wide range of sediment size fractions, from < 32 to 2000 μm and produced predominantly coral sands (>80%) between 125 and 1000 μm in diameter. This is comparable to the grain types found on local reef islands, and it is likely that the most significant supply of this material is from habitats on the atoll-edge side of the platform (which make up ~20% of the total platform area). Quantifying parrotfish functional roles and understanding the drivers behind these processes is important for informing future empirical and modelling studies, particularly as coral reefs undergo a time of dramatic environmental change.

This thesis examines the relationship between the private enforcement of EU competition law and forum shopping with a particular focus on cross-border collective end-consumer redress. There is no coherent framework across the EU for these types of cases. This lack of uniformity has the potential to create recourse to different national courts. Lawyers may engage in forum shopping when filing lawsuits on behalf of the victims of mass torts. Such practices can provide Member States with incentives to amend their laws to attract collective proceedings and create competition between national judicial systems. However, forum shopping is not the only concern. There appears to be a paucity of cross-border collective claims. This is coupled with an apparent lack of motivation for end-consumers to seek a remedy, particularly if the only choice is to litigate outside their own legal regime. Addressing this situation is vital given that end-consumers regularly suffer harm in the form of higher prices, lower output, reduced quality and limited innovation as a result of antitrust infringements but they are rarely compensated due to legal and practical obstacles. To each end-consumer the harm may indeed be de minimis. However, the aggregate harm can amount to a considerable sum. In the absence of effective redress procedures, infringing undertakings retain the spoils of their unlawful conduct. Against this background, this thesis examines the extent to which the conflicts-of-laws rules encourage forum shopping and considers the appropriate forum and the appropriate procedural measures that need to be adopted in order to facilitate effective and equal access to justice for end-consumer victims of EU competition law violations.

This research study analyzed the faculty perceptions of Problem Based Learning (PBL) at one state university campus. There has been an upsurge in student-centered pedagogies as empirical research has demonstrated the benefits of deeper learning, collaboration, and life skills. Empirical studies, in education identify PBL taught students as experiencing increased benefits in the following categories: collaboration skills, critical thinking, solution solving, deeper learning, creates life-long learners, problem solving skills, reflection skills, better retention, and learned 21st-century skills. The objectives of this study were to identify key predictors of perceived student learning associated with PBL pedagogy and the perceived barriers of utilizing PBL by the faculty. Additionally, this study examined whether there are demographic factors that predict the use of PBL. The study was conducted at University-X by surveying faculty of all the schools/colleges. The findings indicated the factors (learning, demographics, and barriers) all related to PBL deployment and sustainability at University-X. As indicated, 90.4% of the responding faculty expressed that PBL has a positive effect on student learning. Participants indicated there were barriers to using PBL. This study revealed an association between recent Professional Development (PD) and the use of PBL by the faculty. Reported recent PD activity is related to PBL adoption by the faculty. This study benefits researchers, administrators, and faculty on the use of PBL pedagogy in higher education and across all fields of education. This study can also benefit sociologists and psychologists on the factors that play in the decisions to utilize active learning programs. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

This thesis examines the representation of odour throughout European literary modernism and other, interrelated fields of cultural production. While the introduction acknowledges Western culture’s traditional subordination of olfaction and smell’s ostensible alienation from language, this study argues that odour and language simultaneously display compelling similarities. Chapter One examines Freud’s influence in determining the modern conception of olfaction, as a figure of comparison with D. H. Lawrence and Bronislaw Malinowski. Freud’s placement of odour as culturally and evolutionarily retrograde is questioned in Chapter Two, which notes the projected technological mastery of olfaction as a trope of utopian fiction, demonstrated in the writing of Aldous Huxley and John Gloag. Chapter Three shifts away from the identification of malodour as a source of modern anxiety to consider the dual commercial and aesthetic significance of perfume. However, these divergent encodings of odour are unified by literary modernism’s persistent recruitment of olfaction as a metaphorical resource; the language of odour denotes a perceived inarticulable quiddity at the heart of the aesthetic object, a feature offered theoretical context by the writing of Walter Benjamin. Chapters Four and Five develop the congruence between the formal properties of odour and language by addressing ‘canonical’ modernist literary encodings of olfaction. Proust’s elision of the role of the sensorily-informed writer with that of the translator supports the consonance of language and odour, a contention further extended in Chapter Five, which considers the olfactory representations of Joyce, and his recognition of the ambiguous semiology of odour as a marker of personal identity. Finally, a conclusion emphasises this study’s extension of the field of modernist olfactory representation beyond Joyce and Proust. The shared semiological instability exhibited by odours and language supports the broader recuperation of olfaction as a particularly apposite modernist sense modality.

Crucial biological processes are often dictated by the action of proteins, including cell growth, intercellular communication and apoptosis. The behaviour and function of proteins, and other important bio-macromolecules, is inherently linked to the 3D con-formation of the polypeptide and the range of dynamics within the structure. The rapidly developing tool, solid-state NMR, is uniquely placed to structurally probe large, non-crystalline macromolecules, such as proteins, and provide data at atomic-level resolution. Amyloid diseases, such as Alzheimer's disease and Parkinson's disease, are linked to neuronal damage caused by toxic species which occur through misfolding and aggregation of naturally expressed proteins. Aggregation of the 36-43 residue protein amyloid-beta (A ) is thought to be involved in the pathology of Alzheimer's disease. In this thesis, solid-state NMR is used to obtain 1 H,15 N and 13 C chemical shifts for U-[13 C,15 N] A 1-40 aggregates formed in the presence of copper, a metal found in abnormally high concentrations in amyloidogenic plaques in Alzheimer's-disease-afflicted patients' brains via post-mortem examination. A suite of 2D13 C-13 C DARR and15 N-13 C DCP experiments alongside 2D and 3D X-1 H,15 N-1 H-1 H and13 C-15 N-1 H. Inverse Detection experiments employed at 100 kHz MAS frequency is employed to obtain chemical shift values. TALOS-N provides torsion angle restraints and secondary chemical shift analysis is performed to identify turn and -sheet regions. The results are compared to previously published models, and indicate the sample is similar to a brain-derived fibrillar structure. 2D13 C-13 C DARR experiments are also performed on selectively labelled samples of A 1-42 with cysteine replacements at locations A21 and A30. This cross-linking mechanism between C21 and C30 has been shown to stabilise an oligomeric form, thought to be the most toxic, on the aggregatory pathway to fibrils. The labels allow detailed characterisation of the turn region between residues 22 and 29. The incorporation of the oligomers into lipid membranes was studied by 1D31 P NMR, specifically to investigate the effect of the oligomers on the stability of the membranes and the effect of cholesterol and curcumin, a potentially therapeutic compound currently of high interest, on this de-stabilisation. Work with collaborators has enabled the oligomeric form to be modelled and the results indicate these toxic oligomers form a hexamer barrel structure, with the hydrophobic sidechains contained within the barrel. The secondary structure of the oligomer is shown to contain 3 or 4 -sheets; with an extended -sheet region between K16-V24, 1 or 2 -sheets between N27 and V36, and then a short -sheet between V39 and A42. A method for inter-molecular –sheet interaction in the hexamer is postulated. A method for further aggregation from this oligomeric form to a protofibrillar form has also been suggested, thus enabling a claim to be made for an on-pathway nature for this oligomeric form.

A large number of animal studies have investigated the effects of hypoxia on the pulmonary vasculature and hypoxic pulmonary vasoconstriction (HPV) is now established as an important homeostatic mechanism for perfusion-ventilation matching in the lung. However, there is a conspicuous lack of studies investigating HPV in human pulmonary vascular preparations. In comparison to the pulmonary vasculature only a limited number of studies have previously investigated the effects of acute hypoxia on the airways. In this thesis the effects of hypoxia on the human pulmonary vasculature and airways was investigated in a number of ex vivo human lung models. In isolated human pulmonary arteries and veins and in ex vivo perfused and ventilated human lungs it was found that hypoxia caused a vasodilation. This finding is at variance with a large body of published literature and it is suggested that a neuronal mechanism could play an important role in the regulation of pulmonary vascular tone under hypoxic conditions in vivo which is not present in the ex vivo models used in this thesis. In exploring the effects of hypoxia on the pulmonary vasculature it was identified that the pulmonary veins could play a more significant role in the regulation of pulmonary vascular resistance than was previously believed. It was also found that exposure of the pulmonary veins to hypoxia precipitated a phasic activity which was suggestive of an automaticity and that the isolated human pulmonary vein model could therefore be used to investigate arrhythmic activity and the efficacy of new antiarrhythmic agents. Exposure of ex vivo perfused and ventilated human lungs to hypoxia caused a reduction in the rate of oedema formation and it is hypothesised that this effect could be mediated by an inhibition of pulmonary vascular endothelial cell contraction and an increase in endothelial barrier function. In isolated human bronchi and ex vivo human lungs hypoxia caused a robust and reversible bronchodilation. The mechanism of hypoxic bronchodilation (HBD) was investigated and it was found that HBD could be mediated by a reversal of the calcium sensitisation mechanism. This mechanism represents a significant therapeutic target for the future development of effective bronchodilator therapies which are not subject to the limitations of GPCR agonists (desensitisation). Studies investigating the effects of changing oxygen concentrations on bronchial tone identified that oxygen concentrations above ambient levels (21%) caused a robust contraction of human airways which could have significant implications for the clinical use of oxygen therapy in constrictive airway disease. In investigating the putative role of hydrogen sulphide (H₂S) as an oxygen sensor it was found that H₂S is an effective vasodilator and bronchodilator in the human lung and could have significant therapeutic potential in the treatment of human pulmonary disease. Further studies have been planned to build on the significant findings in this thesis.

The focus of this thesis is the synthesis of organometallic complexes incorporating the η8-permethylpentalene titanium moiety (η8-Pn*Ti), their characterisation, and their reactivity with small molecules. Chapter One summarises the chemistry of the pentalene molecule, from its instability in the free state to the incorporation of the hydrocarbon into organometallic complexes. The chapter continues with a review of the coordination modes available to Pn and concludes with a brief discussion on the effects of permethylation of hydrocarbon ligands and the advent of permethylpentalene (Pn*). Chapter Two documents the improved synthesis of [Pn*TiCl(μ-Cl)]2 utilising isomeric control imparted on the Pn* synthon, Pn*(SnMe3)2. This protocol permits access to a variety of methylated compounds through metathesis chemistry, of which five have been crystallographically elucidated, revealing the fold angle to be reliant on an interplay between steric and electronic factors. Mono-, bi- and trimetallic {Pn*TiMe2, [Pn*TiMe(μ-Cl)]2 and [Pn*Ti(μ-Me)]2(μ-CH2), and [Pn*TiMe(μ-Me)2]2Mg respectively} species were synthesised dependent on the methylating agent employed and they displayed varying thermal stabilities, with the dimeric nature of [Pn*TiMe(μ-Cl)]2 proving crucial in the formation of [Pn*Ti(μ-Cl)]2(μ-CH2). Chapter Three describes the incorporation of classical organometallic ligands into the Pn*Ti moiety, including the first examples of benzyl, alkyl, aryl, allyl and η1-Cp bound to a PnTi fragment. Seven complexes have been structurally characterised including the first ever crystal structure of a π-hydrocarbon bound Ti species bearing two CH2tBu groups, Pn*Ti(CH2tBu)2, and the fluxional mixed hapticity complex Pn*Ti(η5-Cp)(η1-Cp), whose η1-Cp rearranges via a 1,2-sigmatropic shift. Chapter Four investigates the reactivity of the monomeric dialkyls, Pn*TiR2 (R = Me, CH2Ph, CH2SiMe3 and CH2tBu) with CO2, CO and H2. All four compounds demonstrate “normal” insertion of the CO2 moiety into both Ti-R bonds, revealing a symmetrical bidentate coordination of the RCO2 units. Computational studies have highlighted two competing pathways for their reaction with CO, dependent on the concentration of CO and size of R, which results either in formation of an enediolate or a titanoxirane. The reaction with H2 yields the fascinating trimeric mixed valence, [Pn*Ti(μ2-H)]3(μ3-H), the first structurally characterised example of a trimeric Ti-H species and the first to include a Ti-(μ3-H) moiety. (Pn*TiCl)2(μ-O) is formed by the action of adventitious H2O and possesses a linear Ti-O-Ti bridge with a degree of Ti-O double bond character, supported by crystallographic data and DFT calculations. Chapter Five discusses ethylene polymerisation studies on the monomeric dialkyl complexes Pn*TiR2 (R = Me, CH2Ph, CH2SiMe3 and CH2tBu) using the activators [Ph3C][B(C6F5)4], [PhNMe2H][B(C6F5)4], AliBu3 and H2. Chapter Six presents full experimental procedures for all of the syntheses and reactions outlined in Chapters Two to Five. Chapter Seven details characterising data for all novel compounds, and crystallographic data in the form of CIF files may be found in the electronic version.

The following study examined the perceived developmental influence of the university supervisor-student teacher relationship during the student teaching phase of teacher preparation. Since the supervisor is viewed as the gatekeeper to eventual teacher certification and acts as an evaluator, mentor, and instructor (Borko & Mayfield, 1995; Zimpher, deVoss, & Nott, 1980), findings presented in this study may inform future supervisory practice and shed light on the valuable developmental aspects of this relationship. By utilizing a qualitative case study design, this investigation answered the following central research question: How do the roles of supervisory faculty influence the development of pre-service teachers during the student teaching phase of teacher preparation programs? Data were collected through participant interview, questionnaire, and document collection and analyzed by dividing collected data into overarching codes and themes. The results of this research study hope to inform future practice with respect to university settings in the Commonwealth of Pennsylvania and assist in reviewing and revising, as necessary, the supervisory role and function of the university supervisor-student teacher relationship in the development of pre-service teacher candidates. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Understanding the turnover and storage of C and N in soils is central to the wider studyof biogeochemical cycles. The loss of C and N to the atmosphere can be monitored usingsimple analytical techniques both in the field and under laboratory conditions, with the loss of C (soil respiration) being one of the most studied components of terrestrial biogeochemistry. The sensitivity of these processes to climate change,and the general driving by edaphic, vegetation and climatic conditions are variable and still poorly understood. This thesis considers three issues in contemporary biogeochemistry; 1. How do warming and throughfall reduction (i.e. climate change) alter soil respiration in an upland heathland. 2. What are the drivers of gaseous losses of C (and N) over spatial scales. 3. What controls the turnover of long residence-time soil C on a national scale. Reduction in summer throughfall had a significant effect on soil respiration when monitored over a three year period. Passive night time warming also had a significant effect on soil respiration, and both treatments increased the temperature sensitivity of soil respiration. There was a strong seasonal element thoughwhich suggests a greater temporal resolution is needed to further understand the nature of these fluxes. Assessment of C fluxes on across a nationalscale suggested that the quantity (and possible quality)of Soil Organic Matter (SOM) was a major factor alongside vegetation type when explaining large-scale soil respiration rates under controlled conditions. Using radiocarbon to model the turnover of SOM on a national scale suggested a fundamental difference between vegetation types with regard to the storage of SOM on decadal or millennial timescales. These results reinforce the sensitivity of shorter-term processes,such as soil respiration,to fluctuations in prevailing climatic conditions, but suggest that vegetation type (and therefore litter inputquantity and quality) may be more important when considering the longer-residence time SOM stored in GB soils. Linking concepts across scales is therefore deemed the way forward in an attempt to integrate model predictions of the resilience of different pools of SOM to perturbations such as climate and land-use change.

The Department of Regional Development (DRD), Northern Ireland, designed and constructed numerous highways cuttings in stiff overconsolidated glacial tills during the 60's and 70's. The designs were largely based on ~ntemporary empirical approaches using undrained shear strength, with limited consideration given to the long-term stability of the slopes. Recently there has been an increased frequency of reported slope failures including the failure at Dromore, Co. Down. Consequently Queen's University of Belfast and Roads Service (Northern Ireland), in collaboration With the University of Saskatchewan, have completed a comprehensive hydrogeological research study on a new 18m deep cutting in a drumlin formed in overconsolidated till at Loughbrickland, Co. Down; Northern Ireland. The primary objective was to examine the effects of environmental changes on the groundwater regime with a particular focus on the stability of the slope. A laboratory and field instrumentation programme was carried out including detailed monitoring of head levels and local meteorological conditions. Three years of validated climate and head level data provided a comprehensive understanding of seasonal hydrogeological fluctuations within the Loughbrickland drumlin slope. The head level fluctuations demonstrate a clear relationship with seasonal variation in climate. The· data set provides a basis for further investigation into the effects of cyclic pore water pressure fluctuations and progressive failure on the long-term stability ofslopes. The collated field data was used to create a transient coupled seepage/slope stability model, using SeeplW and SlopelW (Geoslope International, Calgary, Alberta) to analyse the impact of climate on pore water pressure and subsequently slope stability. The model was calibrated using the field and laboratory data and was capable of accurately simulating the annual fluctuations in head level. A sensitivity analysis was completed to .assess the effect of predicted UKCIP climate scenarios on the slope stability of the cutting at Loughbrickland. The model simulates that climate change (UKCIP scenarios) will have minimal effect on the annual cycle of head levels and therefore on the short to medium term slope stability.

Young white men have often found themselves bearing the burden of designs for the improvement of UK society. Official reports reprised this theme following the racially charged disturbances in Northern England's mill towns in the summer of 2001. So- called disaffected young white men were left ambiguously positioned -and immobilised- on the margins of political discourse. In response, this thesis complicates the ways in which young white men in Burnley, a town affected by the violence, may be appreciated as politically capable. In so doing, it prepares for a more imaginative mapping of roles for them in local social progress, post-2001. Ethnographies of boxing and bodybuilding gyms unpack the variety of affective capacities through which young white men live out complex masculine body cultures. These study the inspiration young men find in these carefully engineered and politically enabling places. Although these gyms nestle amidst Burnley's urban hinteriands, and between otherwise parallel lives, they see fragile bonds of affection grow between young white and Asian men. Those bonds represent small, fragile and politically ambiguous gains, which must nonetheless inform proposals for Burnley’s future. The thesis speculates that if such proposals are to be desirable and possible, those same young men must find them persuasive. It therefore recommends placing colloquial inspirations, and a cautious affirmation of capable individuality, at the heart of visions of social progress in Burnley.

The aim of this thesis is to investigate the role of the medial olivocochlear (MaC) efferent system in auditory processing. This was achieved by 'upgradi~g' an existing computer model of the mammalian auditory periphery (Meddis, 2006) to include the effect of stimulating the MaC system. The improved model (Ferry and Meddis, 2007) was evaluated against published physiological data including the responses of the basilar membrane, auditory nerve, and compound action potential. In all cases the model was able to replicate the basic effects ofMaC stimulation at each stage of the auditory periphery as demonstrated physiologically. The model was then used to investigate the suggestion that the MaC system is involved in improving the discriminability of transient sounds such as speech in noise. An improvement in the model auditory nerve response to speech when presented in noise was demonstrated as a result of MaC stimulation. This improvement was then quantified using a series of automatic speech recognition experiments. These experiments demonstrated that MaC stimulation in the model could be used to increase speech recognition performance at all signal-to-noise ratios tested. The temporal effect (or 'overshoot' phenomenon) was then used to characterise the time course of the MaC system psychoacoustically, and also to investigate the role of the MaC system in this phenomenon. The time course measured is in agreement with both temporal effect and MaC system literature and this time course will be added to the model at a future date. The temporal effect was demonstrated in the model only when MaC stimulation is used. This is consistent with the suggestion that the MaC system is an underlying mechanism of the temporal effect phenomenon. The model is proposed as a platform with which it possible to study the complex effects ofMaC stimulation in auditory perception.

Research presented in this thesis describes the development of a novel eukaryotic genotoxicity and cytotoxicity assay based on the expression of the modified firefly luciferase gene (luc+) in the brewer's yeast Saccharomyces cerevisiae. In this biosensor, expression of the luc+ reporter, regulated by the RAD54 DNA damage-inducible promoter, is induced by the presence of genotoxic damage. Inhibition of cell proliferation during the assay is used as a measure of the cytotoxic potential of test compounds. Extensive testing with the S. cerevisiae pGEN -luc+ biosensor demonstrated that it responded appropriately to a wide range of genotoxic compounds and that expression of the reporter was unaffected by non-genotoxic agents. This biosensor has the potential to be developed into a pre-regulator screening assay for the pharmaceutical industry as it provides a rapid, sensitive and inexpensive means with which the genotoxic and cytotoxic potential of compounds can be assessed. Additional research carried out in this study attempted to further improve the biosensor. Proteomic analysis successfully identified a number of proteins that were significantly more abundant in S. cerevisiae cells exposed to genotoxic and hepatotoxic agents. One particular protein (Pst2p) was up-regulated in the presence of all the toxins tested. The function of this protein is unclear but it is believed to be involved in the cell's response to oxidative stress. Incorporation of the promoter that regulates PST2 expression could allow the S. cerevisiae biosensor to detect chemicals that induce oxidative stress in eukaryotes. Such an assay could prove invaluable in the drug discovery where it could be used to identify compounds with hepatotoxic and/or genotoxic properties.

Lake Malawi has a complex, highly speciose, fish community supporting a diverse fishery of great importance as a food source for subsistence communities and to local and national economies. The fish community is also of international importance to scientists interested in the study of evolutionary mechanisms. Little information is available on the structure and ecology of the demersal fish community to help managers understand how best to both sustain fisheries productivity and maintain species diversity. Community level impacts of the demersal trawl fishery in the southern part of the lake are documented but mechanisms for the impacts are unknown. A greater understanding of species distributions and the trophic structure and function of the demersal fish community are required. The principal aim of this thesis was to improve the information base on demersal fish distributions for use in the selection and design o f aquatic reserves, and to enable a more predictive approach to management of the fish community through ecosystem modelling. Specific objectives were: describe spatial patterns of species distributions throughout the lake; determine the trophic structure of the fish community through dietary studies; model community trophic structure using the ECOPATH software, and; evaluate the ECOSIM simulation software for predicting impacts of ecosystem disturbance such as from demersal trawling and the introduction of non-native species. Species catch compositions from over four hundred demersal trawls conducted throughout Lake Malawi were analysed for spatial distribution patterns. Species assemblages were differentiated along gradients of water depth and geographic location. Depth differentiation was characterised by a combination of species replacements, differences in the abundance of shared species, and a reduction in species richness with increasing depth. Only the catfish species were shared by species assemblages from all depths. Assemblage similarity along the geographic gradient was negatively correlated with the distance between sample areas but the proportion of species shared between sample areas showed no clear spatial pattern. A number of hypotheses are proposed as possible explanations for the evolution and persistence of the observed pattern of species assemblages. In particular, the lake-wide consistency in species richness at depth is discussed in the context of species-energy limitations within the system. Finally, the potential application of information on species spatial patterns to the selection of ‘no-take’ conservation areas and aquatic reserves is discussed. Diet analysis, supported by analysis of stable isotope ratios, identified ten main trophic guilds among the demersal fish community ranging across three to four trophic levels. An additional guild was formed to incorporate those shallow water species not often encountered in the demersal trawls that were reported in the literature as feeding on epilithic algae and macrophytes. The mean trophic level o f the demersal fish community for all depths and sample areas, pooled and weighted by the respective areas of lakebed coverage, was estimated at 3.18 with the bulk of biomass (58%) concentrated at trophic level 3.0. Mean trophic levels of fish assemblages were significantly influenced by water depth and sample location. The main influence of depth was realised in the shallow water where mean trophic values in the 0 to 20 m depth band were significantly lower than at all other depths. For many taxa within the demersal fish community there appeared to be a high proportion of trophic-equivalence. It was therefore thought that the community included a number of functional analogues that might be maintained by spatial variability, or perhaps by unobserved behavioural mechanisms operating across species complements. While subtle mechanisms may be at play to support the unusually high species diversity of the lake the results suggested that elimination of a species might result in its subsequent replacement by a functional analogue. Caution should be exercised, however, in making this interpretation based on the rather broad dietary characteristics considered here. Moreover, such functional analogues could also be highly important for the maintenance of ecosystem function and stability through provision of a buffer against environmental change. Loss of these species could thus be highly damaging to the long-term resilience and ecological integrity of the community and, consequently, to the viability of the fishery. Energy flows between trophic levels were estimated through food consumption studies for a selection o f representative species. A trophic model o f the demersal fish community and a graphical representation o f the food web and its energy flows were constructed using the ECOPATH approach and software. The area of the lake modelled was restricted to the southern and western sectors o f the lake to a water depth of approximately 140m. The proposed role of the lakefly (Chaoborus edulis) in the ecosystem was somewhat clarified. Previous study showed that C. edulis was a more important food source to the pelagic fish community than originally suggested, and went on to propose that demersal fish might also rely on consumption of C. edulis larvae. Integration of the demersal and pelagic systems to form a model of the complete ecosystem showed that approximately 57 % of C. edulis production was directly consumed by pelagic fish and a further 2.4 % by demersal fish. The remaining 40 % of production either flowed to detritus, where a certain proportion was recycled through detritivores, or left the system through dispersal as flying adults, some of which returned to the lake to be consumed by surface-feeding catfish. In the demersal zone the role of C. edulis was less significant than in the pelagic. System modelling suggested that although C. edulis provided a direct link between the demersal fish community and pelagic productivity the main pathways for energy flow in the demersal domain were through the consumption of detritus and, to a lesser extent, consumption of copepods by demersal fish apparently migrating into the pelagic for feeding. Integration of the demersal and pelagic components of the Lake Malawi ecosystem indicated that, for the area of lake modelled, the system was more efficient than previously supposed as the demersal fish community was able to utilise much of the pelagic production. In summary, the demersal system appeared to rely most heavily on biomass imported from the pelagic through consumption of detritus and of copepods consumed by fish migrating vertically to feed in the pelagic. Sensitivity analyses were run for a number of ECOSIM simulations based on disturbance scenarios of relevance to the Lake Malawi demersal fish community. Simulations included increased fishing yields, initiation of a deep-water trawl fishery, and the introduction of an alien pelagic zooplanktivore. In all cases the quantitative nature of ECOSIM predictions was sensitive to input values for the ‘vulnerability’ parameter while the qualitative nature of predictions was unaffected. As available data were found insufficient to obtain robust estimates for vulnerability it was concluded that ECOSIM simulations should not be employed to predict the quantitative nature o f group biomass changes but may be used in a qualitative way to predict the direction of change. In all impact scenarios modelled ECOSIM simulations predicted a change in species composition and community trophic structure. It was suggested that the predicted changes in trophic structure might lead to unpredictable outcomes such as trophic cascades and abrupt phase shifts in community structure with associated reduction or stagnation of catches. In conclusion, this study has demonstrated the complex nature of trophic interactions within the Lake Malawi fish community. Modelling simulations have demonstrated the potential for human intervention to disrupt community structure with associated consequences of reduced productivity and stability of the fishery. A number of gaps in knowledge have been identified which, if filled, would greatly increase the robustness of the model and increase its utility as a predictive tool for managing the fishery.

The behavioural responses of aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae) to aphid sex pheromones were investigated in the laboratory and field. In a wind tunnel bioassay, Aphidius eadyi, Aphidius rhopalosiphi, Diaeretiella rapae, Ephedrus plagiator, Praon myzophagum and Praon volucre responded to the aphid sex pheromone components nepetalactone and nepetalactol. P. myzophagum reared on two different host aphid species showed different responses to combinations of nepetalactone and nepetalactol in the wind tunnel, indicating that long term laboratory rearing may influence parasitoid responses to aphid sex pheromones. The ability of two aphid parasitoids to learn aphid sex pheromones through prior exposure in the presence of host aphids was investigated. The generalist E. plagiator showed evidence of associative learning, whereas the specialist Aphidius ervi did not. When A. ervi was exposed to the pheromone without contact with host aphids, the parasitoid response was reduced by habituation. Exposure to aphid sex pheromone during laboratory host attack trials had no effect on the host attack behaviour of A. ervi. In laboratory cage experiments, aphid sex pheromone lures increased the retention of A. rhopalosiphi, but not by Praon volucre, on aphid-infested plants. In a wind tunnel bioassay, aphid sex pheromone enhanced the attraction of A. ervi to a plant-host complex. In the field, aphid sex pheromone lures increased parasitisation rates by A. rhopalosiphi and P. volucre on aphid-infested potted plants. A series of potted plant experiments indicated that the pheromone may increase parasitisation of aphids by A. rhopalosiphi, but not P. volucre, at a distance of 1m away from the lure. The effect of baiting plots of winter wheat with aphid sex pheromone was investigated in two field experiments. In 1996, the number of parasitoid mummies was higher in baited plots than in unbaited plots, and the synchrony between aphid and parasitoid populations was closer in baited plots. In 1997, aphid sex pheromone had no effect on parasitisation levels. The results are discussed in the context of developing a novel aphid control strategy based on the use of aphid sex pheromones to manipulate parasitoid populations.

As the economy of the United Kingdom has improved in the latter half of the 1980s, the distribution of new employment opportunities remains poorly matched to the distribution of the unemployed. With the decline in regional policy in recent years, much government rhetoric has been directed towards encouraging the unemployed and others to move from one part of the country to another in response to job opportunities. Yet the unemployed and the low-skilled continue to exhibit lower rates of mobility than the population as a whole, and there is evidence of socio-economic polarisation in migration. The thesis argues that for many low-skilled, low-paid and unemployed people in the United Kingdom immobility is a rational response to their labour market situation, even when conditions might suggest otherwise. It studies the decision to migrate at the level of the household, set within the interacting spheres of opportunity, aspiration and constraint. The methods of research allow comparisons of manual and non-manual workers, and of two contrasting labour and housing areas, Liverpool and Reading. Quantitative and qualitative methodologies are combined Interview survey and group discussion techniques are combined to examine the relations between social class and immobility, and the influence of local labour and housing markets and community affiliations upon individual and household migration decisions. The survey results demonstrate that migration actions and aspirations are related to position within the local housing and labour market, to housing and employment histories and to stages in household development. The need to look at the household as a dynamic unit is shown, since its needs and those of its members will change over time. The analysis concludes by demonstrating that households balance aspirations, opportunities and constraints, creating a series of 'windows' when migration is preferred though not always a possible option. Whether or not a household will respond by migration depends upon how it balances the elements in decision, particularly those in housing, employment and attitude towards the local community. It concludes that for most low-skilled and unemployed households the most rational course of action is to stay put, despite labour market theories and government exhortations to the contrary.

The practice of retaining students in grade has been studied, researched, discussed, criticized and yet it continues. Dropping out of school prior to graduation has been studied, researched, discussed, written about and continues to be practiced by our youth. Policymakers are often provided quantitative data to consider as they explore, evaluate, and deliberate issues such as the practice of retention-in-grade to assure adherence to standards, or in response to the social, political, and educational problems created by youth who have dropped out from school. Current studies and research into retention and dropping out fail to include the issues from the perspective of the individual; from the standpoint of the dropout. That failure is not a methodological one; the voices of the dropout have not yet been heard. This qualitative study gives voice to the population of at-risk youth. It allows youth who have been struggled and subsequently dropped out of school to tell their story. Their voice becomes a powerful force in the process of educational reform. By considering the needs of the individual, education moves toward doing things with them rather than to them. This mixed methods multiple case study involved collection and analysis of questionnaire data, analysis of demographic information, conducting and analyzing interviews. Participants were youth ages eighteen to twenty-eight years old who chose to return to complete high school graduation requirements through an adult education program. The findings indicate that the most significant issue in their decision to drop out involved the lack of a meaningful with one or more of their teachers. Retained in grade was an explored characteristic but was not a characteristic that all study participants experienced in their school careers. The issue of retention is not as significant as their desire to have a relationship with significant adult in school who demonstrates care and concern. Their story compels policy-makers, decision-makers, and educators to consider more than standards, curriculum, and regulations. They must consider the individual. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Through a research approach of emergence applied to a corpus of academic letures, I developed a theory to explicate the referents of a class of frequently used pronouns ("I," "you," and "we"), which I term the Participatory Pronouns. My theory of the Positioning of Participatory Pronouns resolves the main practical concern of the research participants, which is to place their utterances in contexts for authoritative, intellectually sound, and socially relevant interpretation. At the theoretical level, my theory is a specification of Relevance Theory and resolves disparate previous analyses of pronouns. Overall, my work provides a new paradigm for how referents are retrieved, the language function of these referents, the discourse strategies of the speakers, and what these reveal about academic lectures. Through analysis of seven thousand pronouns from twenty-three university-level, introductory science lectures, my findings emerged from the data as the best explanation for the usage of the participatory pronouns "I," "we," and "you." These pronouns occur frequently in the academic lecture and help to create social and spatial contexts for interpretation. Member-checking interviews and additional tests of validity and reliability verified the limits and generalizability of my findings. The academic lecture is a principal locus of engagement between students and professors. The main concern of the professors in their lecture is how to position their speech in contexts for interpretation so that their message is intellectually sound, socially relevant, and authoritative. My concept of "participant positioning" analyzes the way speakers and listeners place speech in a social and physical context for interpretation. The Positioning of Participatory Pronouns theory explains the associated language functions of juggling, categorical referents, economy, and interchangeability while also accounting for the discourse strategies of extending, exampling, and staturing. Here I explicate the conditions for the occurrence of economy, categorical referents, and interchangeability, which have been noted but not resolved in previous research. My research goes beyond all extant explanations of pronominal reference offering the concept of referent juggling, accounting for switching between several referents designated by the same pronominal form, as well as discourse strategies that are essential to academia. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

One component of Pennsylvania's Science for the Seventies Project, an experimental science curriculum for elementary schools which makes extensive use of instructional television, was an evaluation which compared the effectiveness of the project to that of existing instructional programs. As part of the evaluation, a model was developed and implemented for administering the Television Test of Science Processes via public television broadcast to 3,500 geographically dispersed students. The tests were successfully administered, and the results suggest that the model can be used as a prototype for the administration of other examinations. This text provides background information, a review of relevant literature, a description of the model design and implementation, a summary of results, and further recommendations. (EMH)

A search has been performed for definitive markers for the plasma membrane of leaf protoplasts to enable the positive identification of this membrane in isolated cell fractions. Preliminary investigations with maize leaf protoplasts demonstrated that a plasma membrane-enriched fraction could not be obtained by a conventional method, involving fractionation of a protoplast lysate by differential and sucrose gradient centrifugation. The yield of protoplasts from the leaves of maize was low. A much higher yield was obtained from the leaves of barley. Attempts were made to label specifically the surface of the plasma membrane of barley leaf protoplasts that had been aged overnight. Iodination, using Na¹²⁵I and the solid phase reagent Iodogen, was unsuccessful because of penetration of the membrane by the Na¹²⁵I and resultant indiscriminate labelling. When protoplasts were stained with the electron dense and luminescent lanthanides, terbium and europium, these ions did not appear to penetrate the plasma membrane. Similar results were obtained when whole tissue segments were stained. A spectrofluorometric method was developed for the assay of trace amounts of terbium in membrane fractions derived from prelabelled protoplasts. Fluorescence measurements were subject to interference from a number of sources. Europium-152 labelling studies were performed. The lanthanide dissociated from the membrane at protoplast lysis and redistributed, resulting in indiscriminate labelling. Protoplasts were labelled with a β-cyclodextrin-dansyl chloride complex and 4,4'-diisothiocyano-2,2'-disulphonic acid stilbene (DIDS). A low level of incorporation of these fluorescent labels into protoplast membrane fractions was observed. Experiments performed with the diazonium salt of the auxin affinity label [³H]Chloramben (2,5-dichloro-3-aminobenzoic acid) suggest that it could be used as a surface label for the plasma membrane in intact barley leaf protoplasts. The label was unable to penetrate and binding was permanent. The binding of a structurally similar molecule, diazo-p-amino[¹⁴C]benzoic acid, was less specific. Various cell fractionation procedures were employed in order to separate the labelled (presumptive) plasma membranes. Optimal protoplasts lysis conditions were selected. A 500g supernatant fraction, derived from the lysate, was fractionated on gradients of sucrose, Nycodenz and Percoll. Membrane fractions were also partitioned in aqueous polymer (dextran-polyethylene glycol) two-phase systems. By these separation procedures it was not possible to obtain a plasma membran fraction of sufficient purity to enable further characterization.

Part I of this thesis describes the preparation of the aceto-acetates of steroid alcohols by reaction with diketene, and the examination of their pyrolysis products. Acetoacetates of 3-alcohols were very stable, little or no decomposition to the original alcohol being noticeable. The same was true of other secondary and tertiary alcohols studied. Alcohols in the 17-position having an adjacent 20-ketone gave alphabeta-unsaturated lactones having an acetyl side-chain. Attempts were made to remove this side-chain and thus obtain a lactone ring similar to that found in the carbenolides. Hydrolysis using acid and alkali, and the Haloform Reaction were unsuccessful. The 23-oxime was prepared with the intention of carrying out Beckmann Rearrangement to the amide, followed by hydrolysis and rearrangement to the required product. This was also unsuccessful. The oxime, on treatment with acid or base gave an interesting compound, formulated as 4-(3'beta,17'alpha-dihydroxy-11'-oxe-20'pregnenylidene)-3-methyl-5-isoxazolone. At the other end of the molecule the 3-acetate was hydrolysed, oxidised, and a 1,4-diene system inserted by reaction of the saturated 3-ketone with 2,3-dichloro-5,6-dicyanoquinone. The second part of the thesis deals with an attempted preparation of an 18-oxygenated steroid from hecogenin acetate cyanhydrin. The latter compound on treatment with thionyl chloride gave 3beta-acetoxy-13 beta-cyano-17a-methylene-C-nor-D-homo-5alpha,25D-sp irostane which gave the 17a-ketone on ozonolysis. Hydrolysis of the nitrile group did not give the beta-keto acid expected. 3beta-Acetoxy-17a-oxo-C-nor-D-homo-5alpha,25D-spirostane was prepared, and its cyanhydrin, when treated with thionyl chloride, gave an elimination and not the rearrangement expected. The 17a-methylene compound obtained above was reduced to the 13beta-aminomethyl steroid with lithium aluminium hydride. Nitrous acid treatment of the amine gave the alcohol and not the ring enlarged compound. C-Homohecogenin was obtained by reduction of hecogenin acetate cyanhydrin with lithium aluminium hydride and treatment of the crude product with nitrous acid. Separation of the ketonic fraction with Girard Reagent T gave the required product. The amine from the reduction was characterised as the acetate. This acetate, on treatment with nitrous acid gave a ketone, thought to be the isomeric C-homo ketone.

This dissertation introduces a novel passive acoustic method for estimating the water column sound speed using the directionality of the ambient noise field measured with a vertical line array. In the absence of anthropogenic and biological sources, wind/wave sea surface interaction is the dominant source of mid-frequency noise insonifying the undersea environment. The resulting vertical noise field is anisotropic, with the directionality of the noise environment dependent on the paths of noise from the surface to the receiver. Changes in receiver depth, and associated sound speed, affect the level of ambient vertical noise at shallow elevation angles, providing the sensitivity necessary to acoustically estimate the in situ sound speed profile. Application of a clustering algorithm to an historical set of measured sound speed profiles allows for the characterization of common regional profiles. The scale and resulting undersampled nature of the ocean environment prompts the development of a novel interpolation scheme that retains acoustically important sound speed features in the region between available measurements. Motivated by the vertical stratification and motion of the water column, the interpolation scheme determines an appropriate vertical shift in depth to align sound speed features, enabling persistent features in the interpolated range between measurements. The developed method for inferring the sound speed profile combines sparse measurements of the vertical noise environment with an historical set of measured sound speed profiles and the vertical shifting method to provide an estimate of the in situ sound speed profile, with modeled results having error on the order of common active acoustic inversion methods. Finally, the method is applied to a low-frequency vertical line array data set, with results suggesting the array aperture was insufficient, and that further experimentation is needed.

This thesis examines the question of historical continuity between the sixteenth century Protestant Reformers and patristic/medieval theologians relative to the doctrine of sola scriptura. This principle, that the canonical scriptures of the Old and New Testaments were the highest and final authority for matters of the Christian faith, became one of the major points of conflict between Roman Catholics and the emerging Protestant movement. This study will evaluate primary source material spanning the patristic period to the late Middle Ages to determine if sola scripture was a novel invention of Martin Luther and his fellow Protestants, or if it had been a known and accepted principle prior to the Reformation. It will be argued that the although the doctrine became a source of controversy during the Reformation, it was in fact an established and little contested principle throughout the preceding fifteen hundred years.

Electrification, especially in transportation, is key to objectives mitigating climate change effects. Metal-air batteries, including aluminum-air batteries (AAB), may offer performance and safety improvements over lithium-air batteries by using widely available, inexpensive materials.AAB cell advantages in weight, cost, and safety are countered by high polarization from a persistent oxide film, and by high corrosion rates, most notably in alkaline electrolytes. Much research on these topics has employed pure aluminum or specially prepared alloys to minimize corrosion during experimental evaluation. A key question - could commercial aluminum alloys be used in AAB cells in the immediate future? Thus, twin purposes of this study were to assess the state of current technologies of aluminum-air batteries, and to characterize several commercial aluminum alloys to gauge their suitability for use with common aqueous electrolytes in AAB cells. A comprehensive review of prior AAB works was conducted, including assessments of several other metal-air technologies where common elements, such as catalysts for the oxygen reduction reaction (ORR), are relevant. Effects of anode material composition, and of electrolyte additions as corrosion inhibitors, were considered. Characterization of Al alloy 6061 in alkaline electrolyte was done by weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy. The cathodic effect of second-phase intermetallic particles in Al 6061 to spur galvanic corrosion nearly negated inhibitor benefit in 4M sodium hydroxide electrolyte. Detailed experimental studies were conducted in neutral and acidic aqueous electrolytes. Aluminum alloys 4047 (silicon), 6061 (magnesium/silicon), and 7075 (zinc/copper) were evaluated by half-cell electrochemical techniques, and by use in a flow battery cell coupled to platinum-cobalt or iron-nitrogen-carbon catalysts in air-breathing or oxygen-breathing gas diffusion electrodes (GDE). Post-discharge characterization of anode surfaces was done using scanning electron microscopy, energy dispersive x-ray spectroscopy, and x-ray diffraction. Each alloy manifested different performance, but the strongest influence on cell performance came from ORR kinetics in the GDE. Cell outputs and aluminum utilizations for all materials were similar, regardless of composition. Given the state of the art in ORR catalysts, this work indicates that there appears to be no impediment to using commercial alloys as anode materials in AAB systems at this time.

This research solves current RF propagation modeling gaps by modifying a single-frequency electromagnetic propagation analysis technique for use on communication signals and propagation channels. This research extended the Methods of Ordered Multiple Interactions (MOMI) algorithm to communication signal propagation studies through the use of Fourier decomposition thereby allowing the analysis and prediction of communication signals propagating over rough surfaces. Current methods of predicting and analyzing communication signal propagation rely on either using only a single frequency instead of a band of frequencies, stochastic techniques that model the environmental effect on the propagated signal, or on empirical models based of large amounts of measured situational data. None of these methods fully capture the actual effect that an environment imparts on a communication signal as it propagates. This research also modifies the Physical Optics (PO) algorithm utilizing Fourier decomposition to compare the Extended MOMI algorithm to. Both algorithms are applied to propagation scenarios utilizing frequencies in the 1-GHz and 5-GHz bands against a series of signal bandwidths and surface roughnesses. The results are analyzed singularly for Extended-MOMI and against Extended-Physical Optics to better understand the benefits associated with using the Extended-MOMI, the limits of the narrowband approximation, the errors incurred when utilizing a simpler or faster propagation algorithm, and to generally characterize these rough surface propagation channels. This research also defines and explores which metrics provide the best characterization and utility for communication signal propagation with the additional insights of amplitude-frequency-phase relationships the new algorithm provides.

The following dissertation will present the issue of declining membership and baptisms over the past fifty years in Sandy Creek Baptist Association of Illinois, (SCBAI). This study will show the need for collaboration by the Association members to address this issue and encourage the members to consider spiritual formation towards vitality. The study will include surveys seeking pastoral input, Director of Missions input, and membership of the SCBAI input regarding missional endeavors in local ministries. A plan toward new missional goals in the churches of SCBAI and in the local communities will be discussed. The goal of the project is to help churches in the SCBAI see the need for transforming change and developing current members to become more missional in their endeavors for Christ, teaching them on how to be aware of missional needs, this is done by researching the subject of being missional and researching the characteristics of churches that are in the decline transition. The spiritual development program will be developed using researched methods and approaches of leading authors on missional growth. The CARE program being introduced means a careful or intentional structuring approach to adapting to current needs of all generations while teaching redemptive principles and equipping all believers towards an incarnate missional approach.

This thesis presents a measurement of the production cross-section of a Z boson in association with at least one or two b-jets. This final state occurs in the Standard Model and can be used to test predictions from perturbative quantum chromodynamics. It is also an important background for several processes including Higgs production, with the Higgs decaying to a b-quark pair, in association with a vector boson as well as searches for physics beyond the Standard Model which contain leptons and b-jets in the final state. The measurement is done using data collected by the ATLAS detector from proton-proton collisions at a center-of-mass energy of 13 TeV at the LHC corresponding to an integrated luminosity of 35.6 fb^-1. The integrated and differential cross-sections are measured at the particle level for both the electron and muon decay channels of the Z boson. The results are compared to predictions from several Monte Carlo predictions.

Abstract: Trade-offs between wood density and radial growth rate in white spruce were investigated. Decreases in wood density associated with increased radial growth rate have been well documented in several tree species, including white spruce (Picea glauca (Moench) Voss). One of the goals of the Region H white spruce Controlled Parentage Program is to increase stem volume at rotation; however, the Forest Genetic Resource Conservation and Management Standards of Alberta (2016) require program proponents to consider the indirect selection of correlated traits, including wood density, when selecting for increased growth rates. Resistograph drilling resistance (%), Pilodyn penetration depth (mm), wood specific gravity and diameter inside bark (mm) at breast height were measured in 40 different families from three progeny test sites at age 26. Two to eight trees/family/site were selected for drilling resistance and diameter at breast height measurements, two to eight trees/family for two sites were selected for penetration depth and two to seven trees/family across all three sites were selected for wood specific gravity assessment. Analyses included phenotypic and genotypic correlations between the various traits, regression analyses for estimating wood specific gravity using drilling resistance and penetration depth measurements and calculation of narrow sense heritability and breeding values for drilling resistance, penetration depth and diameter inside bark. These breeding values were plotted against the breeding values for height (cm) at age 25, which were provided by the Government of Alberta. A paired t-test showed that significant differences existed between drilling resistance measurements taken from the north and east aspects of individual trees, but a significant difference was not found between penetration depth for the same trees. Significant differences existed between sites for all four traits; however, significant differences existed only for drilling resistance between families. Additionally, coefficients of variation showed that the variation in diameter was two to three times greater compared to any of the wood density measurements. Phenotypic correlations between the various quantitative traits were typically moderate in strength (r ~ 0.5) at both the individual- and family-level and all were significant. The relative standard error was approximately 5-10% of the respective correlation coefficient. Multiple linear regression showed that both drilling resistance and penetration depth were relatively poor predictors (r2 ~ 0.4) of wood specific gravity at both the individual- and family-level. There was no genotype-by-environment interaction detected for drilling resistance or Resistograph, but there was for both penetration depth and diameter inside bark. Narrow sense heritabilities were generally low for diameter at breast height (h2 < 0.15) and higher (h2 > 0.3) for drilling resistance and penetration depth, except for Hay River, which showed the opposite response for drilling resistance (h2 = 0.11) and diameter inside bark (h2 = 0.42). The relative standard error associated with each heritability estimate was generally high (30-150% of the heritability). Genetic correlations for all traits were significant and weak to moderate (0.3 < r > 0.7) at the individual-level and very weak (r < 0.15) and not significant at the family level. At the phenotypic level, there is some evidence that increased radial growth rate is associated with a decrease in wood density; however, the decrease in wood density is very small (< 10%) and the variation in wood density is much lower than that found in diameter. Additionally, the range of wood density and level of variation in the Region H white spruce Controlled Parentage Program was similar to wild stands in Quebec, indicating that there was no loss in wood density through selection for height. Resistograph appears to be a more sensitive measurement for iv assessing wood density compared to Pilodyn, as it was able to delineate significant differences even at the family level and provided the highest estimates of heritability with relatively lower associated standard errors. The genetic correlation between drilling resistance and diameter inside bark was virtually non-existent (rg = -0.08). Forest companies should monitor the wood density of natural and artificially-regenerated stands on an ongoing basis and assess wood density within each tree improvement program and each generation within a respective program to ensure that mean wood density does not decline compared to natural stands over time.

Understanding how individuals make meaning of their faith has been researched for generations, with some important studies (Fowler 1981; Parks, 2011) delineating how such individuals construct and develop their faith over a lifetime. Likewise, a great deal of studies have explored how college students approach faith (Astin, Astin, & Lindholm, 2011; Chickering, Dalton & Stamm, 2006), and how universities can support such exploration. However, little research has been completed to investigate how students transition from college experience to adult life (Fox, 2011), and no research to date explores how students make meaning of their faith in the post-college transition. To fill that gap, this dissertation presents a qualitative, phenomenological study aimed at providing insight into how recent college student leader graduates of a Christian institution make meaning of personal faith during the post-graduation transition.To better understand how these Christian college student leaders constructed their faith after college, the researcher employed one-on-one interviews, using the general interview guide approach (Patton, 2002), and a pre-interview questionnaire from 15 recent graduates from a religiously affiliated, liberal arts university in the Midwest. Participants provided rich descriptions of their current faith through personally chosen words and metaphors. They expressed a desire to build supports for their faith in the midst of transition by creating a place for their faith to be integrated in their new life experiences, seeking opportunities to practice their faith, and building connections to people who helped and challenged their faith. Finally, they detailed the faith challenges they faced as a result of transition out of university life.Through analysis of faith descriptions, the findings of the study revealed that the transition fostered reflection on the meaning of participants’ faith, and the supports and challenges of their faith both in college and in the midst of transition. The participants in this study also expressed a desire to reflect on the construct of their faith while maintaining their beliefs, or faith content. These recent graduates were also focused on building supports for their faith which would help them navigate challenges they faced in their transition and future life. Finally, as they reflected on their faith and focused on building such faith supports, they used the faith supports they found in their college experience as comparison points for their current faith needs.Research findings suggest that more could be done by students, higher education professionals, and faith communities to prepare students for the post-college transition and to support graduates as they reflect on the construct of their faith and build faith support structures. Ultimately, these groups need to become more educated about this phenomenon to help future graduates find, create, or integrate into various faith communities following the college experience.