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The Sullivan County School District, a pseudonym, is a specialized district in NYC catering to newcomers and students at risk for high school dropout. In the 2022-2023 school year, there was a significant increase in enrollment of asylum-seeking students living in shelters. Using an improvement science approach, the aim of this study was to support principals in developing high-level learning experiences for asylum-seeking students. Two primary drivers included increasing (a) collaborative work among 10 principals in a networked improvement community and (b) educational support by building capacity among teachers, guidance counselors, and social workers. The goal of the first Plan-Do-Study-Act cycle was to collaborate in winning $1 million in grant funding. Between October 2023 and January 2024, NIC principals began intervisitations aimed at (a) learning from each other about supporting teachers working with special populations, (b) observing how school leaders addressed the identified problem of practice in real-time, and (c) sharing current experiences of students, teachers, and leaders. The researcher also examined his own leadership actions and organizational change through two frameworks: adaptive leadership theory and communities of practice. Four leadership themes emerged: the value in making mistakes, the importance of building trust and fostering vulnerability, and learning when to let go. The most valuable lesson was the acceleration of learning that occurs when a group of individuals, each bringing unique expertise and experiences, are willing to trust and be vulnerable with one another for the greater cause of supporting students. [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 quantitative study examined the impact of a multi-subject double-dose STEM intervention on the academic achievement of underprepared 9th-grade males. The intervention consisted of heterogeneously grouped core classes of Algebra 1 and biology accompanied by a second multi-subject (Algebra 1 and biology) support class. This nine-week study did not show a statistically significant difference in the biology and Algebra 1 first-quarter averages of the students who received the intervention compared to students who received a general study skills class or no intervention. However, students who received the intervention had lower first-quarter failure rates in biology and Algebra 1. This group also had more students with first-quarter biology averages of B or higher. This result may be due to the biology teachers who helped teach the support class and stressed topics that were interesting and relevant to male students. Regarding Algebra 1, the general study skills class had a greater impact on the first semester averages and the percentage of students earning a B or higher. These results show the importance of stressing noncognitive supports related to academic discipline when remediating Algebra 1. Future studies should focus on a more deliberate integration of research-based noncognitive supports for males into the multisubject support class. [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.]

Oxygen deprivation (hypoxia) is an important immunosuppressive mechanism in cancer. The lack of proper blood supply and a high local metabolic demand depletes immune cells of key metabolites including oxygen. Tumour hypoxia is particularly hostile to antitumour cytotoxic CD8+ T cell function by repressing clonal expansion and by eliciting immune checkpoint mechanisms. However, T cells cultured ex vivo at low levels of oxygen outperform ambient oxygen-cultured counterparts in terms of antitumour cytotoxic function following adoptive cell transfer to a tumour-bearing host. This indicates that hypoxia can play a physiological role in regulating and, depending on the context, boosting T cell function. This dissertation is divided into 3 chapters, each dedicated to describing different physiological roles of hypoxia in CD8+ T cells. Chapter 1 addresses the role of oxygen sensing by the HIF pathway in fueling the hypoxia-driven increase in CD8+ T cell function in adoptive cell transfer settings. Increased HIF signalling achieved through genetic or pharmacological manipulation of the HIF pathway shaped T cell function and differentiation in a similar manner to exposure to low oxygen tensions. Exacerbated HIF signalling was immunosuppressive whereas a controlled or temporary increase in HIF activity was immunomodulatory and improved the cytotoxic function of CAR-T cells. A single day of hypoxia-conditioning during T cell activation followed by 6 days of expansion in ambient oxygen, was sufficient to modulate metabolism, differentiation and to improve in vivo antitumour cytotoxicity of CAR-T cells, thus showing the power of oxygen tensions in shaping T cell function. Chapter 2 focuses on the metabolic adaptation to low oxygen in CD8+ T cells, and characterises the immunomodulatory role of glutarate, a newly discovered hypoxia-induced metabolite. Glutarate was found to inhibit α-ketoglutarate dependent reactions and to modulate T cell differentiation and improve antitumour CD8+T cell function. Administration of esterified glutarate in tumour-bearing animals significantly improved infiltration of CD8+ T cells in tumours and extended animal survival, thus revealing the potential of glutarate to be used as a metabolic target. Chapter 3 describes the role of nitric oxide, another hypoxia-induced metabolite, in T cell function. Nitric oxide was found to be endogenously produced by T cells and to mediate their tissue infiltration and antitumour function. Overall, the data presented here show how oxygen tensions can profoundly shape T cell function through modulation of T cell differentiation and metabolism and informs about new strategies of T cell modulation that can improve immunotherapy.

In this thesis, we focus on reversible addition- fragmentation chain transfer (RAFT) polymerisation in scCO2 with both molecular chain transfer agents (CTAs) (DDMAT, CPAB, CTPPA) and polydimethylsiloxane (PDMS)-based macromolecular CTAs (macro-CTAs) soluble in scCO2 (PDMS-DDMAT, PDMS-CPAB, PDMS-CTTPA), for the dispersion polymerisation of methyl methacrylate (MMA). Although the use of PDMS-DDMAT macro-CTAs led to stable PMMA particles, successful RAFT control was not attained, and part of the macro-CTA remained unreacted. Therefore, RAFT dispersion polymerisation of MMA in scCO2 was investigated using DDMAT and comparing to other molecular CTAs. Despite its low chain transfer constant (Ctr) towards MMA, DDMAT showed good control over PMMA molecular weight. A thorough investigation of the nucleation stage revealed an unexpected "in situ two-stage" mechanism that explains this result. Finally, a correlation between polymerisation control and the degree of solubility in scCO2 of the CTAs was stablished, giving rise to a guideline to select the best molecular CTA for MMA RAFT dispersion polymerisation in scCO2. The use of PDMS-CPAB and PDMS-CTPPA, which present chain-ends of high Ctr towards MMA, allowed an overall improvement of MMA polymerisation and RAFT control in scCO2 compared with PDMS-DDMAT. The good solubility of these macro-CTAs in scCO2 and the good control observed led to the formation of PDMS-b-PMMA block copolymers, suggesting the establishment of a polymerisation-induced self-assembly (PISA) process. This is a step forward towards PISA polymerisation via RAFT in scCO2 with fluorine-free macro-CTAs.

The global population will increase dramatically during this century which, together with the climate crisis, will pose an enormous challenge for food security. We will need to balance boosting food production with reducing agrochemical use in order to preserve natural ecosystems. To do this, exploiting the benefits that the rhizosphere microbiome has on plant health, growth and resistance to biotic and abiotic stresses has been proposed as a feasible strategy. In my project, I examined the interaction between barley, the fourth most important cereal crop, and the widespread beneficial bacteria Pseudomonas fluorescens. Plants can actively shape their rhizosphere microbiomes mainly through the secretion of root exudates whose composition depends greatly on host genotype. The ability of different microbes to utilise these exudates determines their success in the rhizosphere, which results in a shift in the rhizobiome composition. In my PhD, I first investigated the effect that barley genotype exerts on the overall rhizosphere microbiome and on the soil Pseudomonas population. I next examined the genetic features of the Pseudomonas populations linked to two particular barley cultivars, Chevallier and Tipple, and identified a set of cultivar-specific genes among the rhizosphere Pseudomonas isolates. These genes fell mainly into two categories: substrate transport and central metabolism, supporting the role of root exudates as the primary drivers of rhizosphere microbiome assembly. Next, I analysed the exudates composition of Chevallier and Tipple, and observed that the secretion of sugars and organic acids were the major differences between them. Finally, I screened a Chevallier x Tipple population for the secretion of fructose as a potential determinant of Pseudomonas recruitment, highlighting two large QTL in the barley genome. Overall, the ultimate objective of this project is to provide a basis to select more efficient biocontrol strains, and breed plants with an improved ability to recruit beneficial Pseudomonas.

Disproportionate representation and educational inequity are issues embedded in the history behind current services provided to students who are culturally and linguistically diverse with complex support needs (Artiles et al., 2005; de Valenzuela et al., 2006; Hosp & Reschly, 2004; Klingner et al., 2005). Research has shown that English learners with disabilities should have access to both special education and Title III services as required by law (de Valenzuela et al., 2006, 2018, 2016, 2022; de Valenzuela & Copeland, 2018; Kangas, 2014, 2018, 2019, 2021). Because there is very little research focused on the needs of English learners with complex support needs (Rivera et al., 2019), this study adds to existing literature. This quantitative study uncovers issues of educational inequities related to: (1) the identification of these students as English learners; (2) their access to Title III services; and (3) the instructional settings in which they are educated for culturally and linguistically diverse students with complex support needs. Disaggregated student level data from a large school district in the southwest from the 2018-2019 school year was used for cross-tabulation comparisons using Pearson Chi-squared statistical test for association. Results from this research suggested that students in the district identified with Intellectual Disability (ID) or Multiple Disabilities (MD) were less frequently identified as English learners, parents of children identified with Autism (ASD), Developmental Delay (DD), ID, MD, or Traumatic Brain Injury (TBI) were more likely to opt out of Title III services, and English learners with a disability were less likely to be re-designated as fluent in English. Additionally, English learners identified with ASD, ID, and MD were placed in the most segregated special education setting at a higher rate than students with other disabilities. Additional analyses suggested: (a) slightly more male students were placed in the most segregated setting; (b) Asian students were mostly placed in the least segregated setting; (c) and American Indian/Alaskan Native, Black or African American, and students identified as Two or more races had the highest percentage of students identified with a disability than other race/ethnicity groups. Results suggested that to protect the rights to services for students who are culturally and linguistically diverse with complex support needs, clear guidance from district documents on policies should be provided to schools so that federal laws and regulations are not misinterpreted by school administration and teachers. [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.]

Standardized testing is generally regarded in schools today as the primary way to measure and determine student achievement. Student performance determines the degree to which schools, teachers, and students are identified as being successful. The problem being investigated by this study was that all students are spending too much classroom instructional time being assessed to predict how they will perform on annual standardized assessments (Zaleski, 2016). The purpose of this study was to compare the ability of two different diagnostic tests currently in use to predict how students would perform on the end of year state assessment for ELA and mathematics in grades three through five in a large District in south Florida. Specifically, this study analyzed the i-Ready Diagnostic and the District created interim assessment to identify the degree to which both assessments are able to predict how students will perform on the state's end of year state assessment. The relationship between the two diagnostic instruments was investigated through correlation design. The differential predictive ability of the two diagnostic assessments was explored through bivariate and multiple regression analyses as well as the calculation of sensitivity, specificity, and positive predictive values across grades (third, fourth, and fifth) and content areas (language arts and mathematics). On the surface, correlation and regression analyses suggest a high level of similarity between the two diagnostic tests. However, further exploration of sensitivity, specificity, and positive predictive values shows marked differences across the two diagnostic instruments. The pattern of differences is consistent across grades and content areas. Discussion addresses the challenges in frequent diagnostic and accountability testing and the need to make decisions that will best serve the needs of students. [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.]

Biocatalytic processes using transketolase have previously been developed in order to produce polyalcohols; an important class of chiral molecule, often used for the synthesis of active pharmaceutical ingredients. Transketolase catalyses asymmetric carbon-carbon bond formation by transferring a two-carbon moiety between a ketose and an aldose sugar. Nowadays, there is a focus on sustainable processes, based on the use of renewable feedstocks, in order to reduce energy consumption and waste production. The aim of this study was to establish novel methods for the evaluation and optimisation of the transketolase-catalysed upgrading of L-arabinose and D-galacturonic acid, the major pectin components of sugar beet pulp, a by-product obtained from sugar beet bio-refineries, and to explore their subsequent amination. The first objective involved transketolase production, activity evaluation and the development of a detailed kinetic model for the bioconversion of L-arabinose to L-glucoheptulose using cell lysates. Optimising cell growth and protein expression for the H461Y transketolase mutant and using clarified lysate as biocatalyst, an initial reaction rate of 51 µmol L-1 min-1 was reached. This is the highest initial reaction rate for the production of L-glucoheptulose reported to date. It was found that the high Michaelis constant of L-arabinose determines the rate of the overall reaction, and that Lithium hydroxypyruvate is inhibitory at concentrations > 1 mM. Screening of a library of transaminase enzymes identified a transaminase that could convert L-glucoheptulose to (2S,3S,4S,5R)-6-aminoheptane-1,2,3,4,5,7-hexaol. A kinetic model for the L-arabinose bioconversion using pure H461Y transketolase as biocatalyst was also generated. Comparison of the kinetic parameters of the purified and lysate forms of the enzyme indicated that there is no significant difference between the two enzyme preparations. A second objective was to assess the utilisation of transketolase for the upgrading of D-galacturonic acid. Mutant H461Y was identified as also being able to achieve the bioconversion of D-galacturonic acid into 2,3,4,5,6,8-hexahydroxy-7-oxooctanoic acid. A detailed kinetic model of this bioconversion was also established. This showed that H461Y transketolase presents higher affinity for D-galacturonic acid than for L-arabinose since D-galacturonic acid bioconversions reached completion in less than 12 hours. The model showed that Lithium hydroxypyruvate exhibits inhibition to the reaction at concentrations > 1 mM. This is consistent with the L-arabinose bioconversion study. Optimum conditions for 2,3,4,5,6,8-hexahydroxy-7-oxooctanoic acid synthesis would involve the use of high D-galacturonic acid and low Lithium hydroxypyruvate concentrations. Based on the insights of the kinetic model for the lysate TK, options to improve the productivity of the bioconversion process were finally explored. The most productive conditions for the synthesis of L-glucoheptulose in a fed-batch process at preparative scale involved using high L-arabinose (111 mM) and low Lithium hydroxypyruvate (>10 mM) concentrations. Under the optimised conditions the maximum L-glucoheptulose productivity achieved was 56.8 mg L-1h-1. Overall, this work has established the foundations for the biocatalytic upgrading of L-arabinose and D-galacturonic acid from SBP as a sustainable feedstock. The products formed have potential applications in hypoglycaemia and cancer treatment.

Introduction: The condition of obesity has been classified as a pandemic , given that it is negatively impacted health in almost every country in the world (1). Scotland has one of the worst obesity records in the world and one of the highest rates of all OECD countries (2). Scottish men and women in the most deprived areas had higher rates of obesity in 2016 in comparison with less deprived areas (3,4). Its alarming increasing trend year on year and the magnitude of the level of obesity over the last 30 years, coupled with the causality network which appears to be rooted in health inequities has been made obesity a titan challenge of the 21st century (1,5,6). No country in the world has reversed the challenge of obesity. The community food environment has been identified as one of the environmental causes of obesity (7-9). The high presence and accessibility of less healthy food sources appears to determine an increased availability of high-energy dense food, and the lower presence and accessibility of healthier food outlets also decreases the availability and shopping possibilities for more nutritious products (7-9). Both scenarios encourage a more frequent consumption of obesogenic food, promoting a rapid and sustained weight increase in all age groups, but especially among adults and elders (6,7,10). This thesis is the first study in Scotland that has mapped a complete foodscape or food map in a deprived neighbourhood and identify some key contributors that promote obesity. Methodology and methods: the study was conducted in a Scottish urban neighbourhood, which is low-income with high levels of poverty and obesity and poor dietary patterns. Data collection made use of a combination of different databases and approaches, including ethnographic fieldwork and online validation. Predominance, proximity and density of all type food sources, and healthier and less healthy food sources were calculated, using the Quantum Geographic Information System (QGIS) software. Food sources were categorised using 15-point classification tool, proposed by Lake et al (11). Accessibility to these sources was assessed separately for general stores and healthier and less healthy categories. Results: Findings reported a wide range of outlet types and confirmed an obesogenic food environment in the neighbourhood. Food sources related to deprivation were also present, such as food banks, whereas others such as organic food outlets which are related to more affluent areas were absent. A set of ready-made food at a low price, easy to collect or delivery at home preparations was present in over 30% of the establishments and are described in the thesis. These preparations were highly popular among the residents, and almost all the menu options were served in extra-large portions. The food outlets' showcases were often in a deteriorated state with a preponderance of special cheap offers. Most of the establishments had a small sit-in area, while promotion of food delivery and takeaway was high. A higher proportion of less healthy food sources (27.7%) than healthy food sources (5.5%) were present within the neighbourhood. Less healthy food sources, such as fast-food outlets, takeaways, and convenience stores, were highly accessible and offered a wide range of high-energy dense foods. This scenario is known as food swamp. On the opposite side, the few healthier food sources, such as supermarkets, and fruit and vegetable stores, were located further away from households than the less healthy food sources. This scenario is known as a food desert, and alongside a food swamp, they confirmed that the geographical area mapped, anonymised to Whitewood has a highly obesogenic food environment. This environment appeared to be encouraging unhealthy eating patterns among residents and people working and studying in the area. Conclusions: This complete food exposure mapping showed for the first time in an area of intense deprivation, the features of a low-income food environment. Regarding the obesogenic characteristics of the food environment, results resonated with previous investigations. The presence of a food swamp and a food desert and the high accessibility of less healthy food in comparison with healthier establishments, is a scenario described previously in literature in other countries, including the US and Canada (12,13). According to Glanz et al. and Story et al. there are common drivers related to deprivation that influence a less healthy food shopping behaviour among residents, contributing to the weight gain process (7,8,14). Although the obesity causality network is hugely complex and several determinants can potentially influence eating patterns, the community food environments quality and accessibility may be part of the factors that encourage inhabitants to eat less healthy food regularly. Obesity causes are potentiated by health inequities, and there is an urgent need to tackle the obesity problem from the roots, using a multilevel approach (5,6,15). Intervening within the food environments in deprived neighbourhoods is part of the Scottish government new food policy; however, more articulated initiatives are needed to fight against obesity, starting from tackling the roots of poverty (16,17).

The degradation of tropical forests is a significant problem transforming these ecosystems, contributing to greenhouse emissions and biodiversity loss. However, quantifying the impact is difficult, because different factors can indicate that a forest is degraded, and there is a wide variety of definitions and drivers. The motivation of this research is to contribute to the technical challenge of mapping and measuring forest degradation by evaluating the variations in forest structure of a degraded tropical forest and explore the potential of SAR for accurately achieving this goal. The forests of Bajo Calima – Colombia are under pressure from unplanned gold mining and selective logging at different intensities, which has changed their structural properties. In this thesis, I investigated the structural variabilities in the forests of Bajo Calima, and connected them to forest degradation using a combination of multi-temporal in-situ data, light detection and ranging (LiDAR) data, multi-frequency and time series SAR data. Firstly, forest structure data collected from field plots in 2014 and 2017 were classified using K-means cluster analysis. Aboveground biomass (AGB), tree density and basal area and trunk diameter (DBH) were the variables that better explained the variations in forest structure, and with a precision of 0.77% four levels of disturbance were identified in the area: low to severely degraded forest. Secondly, I investigated the potential of integrating multi-frequency SAR data: ALOS PalSAR-2, Sentinel-1, interferometric coherence, and the digital elevation model (DEM) from TanDEM-X, in combination with LiDAR and field data to retrieve the forest structure parameters derived from the field data analysis. A Random Forest (RF) machine-learning approach was used to map AGB, tree density and basal area, and to classify the area into different levels of disturbance. Results showed a very good ability to retrieve information from different metrics of forest structure and categorise them according to different degrees of forest disturbance. Accuracies were higher than 90% for the regressions, while Kappa coefficients were above 0.80 for the classifications. Using the DEM derived from the X-band was key to achieving these higher accuracies. Finally, capabilities of ALOS PalSAR-1, ALOS PalSAR-2 (2007 – 2018) and Sentinel-1 (2014 – 2017) were assessed by integrating time series responses from multi-frequency SAR data in order to evaluate forest degradation as the significant variation in forest structure. Results were promising, demonstrating with high accuracy (≥ 88%) that by using the model derived from this study, it is possible to identify areas that have been considerably impacted by degradation over time.

This research explores the psychological wellbeing and experiences of international doctoral students from the Middle East and North Africa (MENA) region who are studying abroad during a time of conflict in their home-countries. It is necessary to develop an understanding of this growing cohorts’ experiences as there are many potential vulnerabilities where their psychological wellbeing is concerned, which may make their lives more challenging than the average person or international student. As there are many psychological aspects of their experience that we may not yet understand, two broad research questions guide this investigation: (1) How is this cohort affected by home-country conflict while abroad and (2) how do they cope with any effects. A sequential exploratory mixed-methods design was employed to answer these questions with rigor in attaining both depth and breadth, where a primary qualitative investigation is emphasized, followed by a supplementary quantitative investigation. The qualitative phase comprised 24 semi-structured interviews with Syrian (n=14), Palestinian (n=5) and Turkish (n=5) UK-based international doctoral students; an interpretative phenomenological analysis framework guided the research design, and coding and identification of the following superordinate themes: Triggers and Facilitators of Stress, International Student Dynamics, Psychological wellbeing, National Identity, and Coping. These themes provide a rich foundation for understanding the significant factors which comprise the experiences of this cohort and which influence their psychological wellbeing. The qualitative findings were converted into quantitative survey items and aggregated with a focus on measuring dimensions of psychological wellbeing, resulting in a novel tool: Remote Exposure to Trauma Impact Scale (RETIS). The quantitative phase comprised of designing and pilot testing RETIS and exploring triangulation and generalizability of the qualitative findings to address a third research question asks (3) how do quantitative findings from a different sample of the same population converge with or diverge from the qualitative findings? A low respondent rate (N=18) limits the depth of statistical interpretation, but quantitative findings offer early support for RETIS and are consistent with the qualitative findings. Both phases strongly suggest the participants experience poor psychological wellbeing, high levels of perceived impact from events occurring in home-countries, and are largely predisposed to intersectional psychological distress given their strong psychological and emotional ties to events occurring in their home-countries, while also pursuing advanced degrees in host environments. Findings also provide unexpected insight into the psychological wellbeing dynamics of this group concerning the role and influence of their held identities. Lack of comfort with explicit coping mechanisms and the use of professional mental health services exacerbate the vulnerability of this group, given their adverse circumstances. However, their high-functioning capabilities suggest there may be an inherent resilience across this group. Overall, this study highlights the complex, intersectional stresses to which this growing cohort is susceptible. This thesis contributes rich empirical insights, offers the RETIS tool through rigorous tool development as part of mixed methods research, and contributes to knowledge through a two-stage conceptualization of a novel theoretical construct, Remote Trauma, which addresses a gap in the literature concerning direct trauma experiences involving adverse events which occur remotely.

Breast cancer is the most common cancer among women worldwide. The current gold standard for breast cancer screening is triple assessment using clinical examination, histological assessment and imaging (a combination of X-ray mammography and ultrasound). However, this approach limits the understanding of the subtypes and progression of the disease in terms of biochemical changes. Vibrational spectroscopy has demonstrated its potential to provide diagnostic information. Raman and FTIR spectroscopy can facilitate the prediction of the biochemical progression for different diseases in a rapid non-destructive manner. Raman and FTIR spectroscopy was used to characterise and differentiate normal breast and breast cancer as well as different subtypes and grades of breast cancer. Tissue microarrays (TMAs) are valued in cancer research due to the minimal tissue requirements and excellent correlation with whole tissue sections. TMAs containing breast cancer and normal breast samples were analysed with Raman and FTIR spectroscopy. The cancerous samples include different grades and subtypes and represent similar tribal origins in Nigeria. A total of 578 samples were analysed with Raman spectroscopy, while a total of 273 samples were analysed with FTIR. Biochemical changes were detected for luminal, HER2+, and triple negative breast cancer for grade I, II and III. Spectral data revealed key differences in the concentration of biochemical compounds, such as, lipids, nucleic acids and proteins. Principal component analysis (PCA) was able to identify differences that lead to accurate and reliable characterisation of normal breast tissue, and different subtypes and grades of breast cancer. Linear discriminant analysis (LDA) confirmed 86% sensitivity and 89% specificity for the Raman spectroscopy results and 92% sensitivity and 86% specificity for the FTIR results. The identified differences represent a stepping stone towards a complete understanding behind the nature of different subtypes and cancer progression. In summary, vibrational spectroscopy showed a good potential in characterising and identifying new spectral markers. These findings provide an insight into different subtypes of breast cancer and the chemical pathway to the cancer progression associated with different grades.

The research described in this thesis focuses on different areas of organozirconium chemistry. Firstly, four compounds with a cis-bicyclo[3.3.0]oct-2-ene backbone were synthesised to target orphan nuclear receptors LRH-1 and SF-1. The key reaction to construct the bicyclo[3.3.0]oct-2-ene involved the zirconocene-mediated cyclisation of 1,6-enynes (prepared via multi-step synthetic routes) followed by further elaboration with the insertion of a 1,1-dihalide alkyl carbenoid and a lithium phenyl acetylide. Secondly, a wide range of benzyl carbenoids were inserted into unsaturated zirconacycles which afforded the corresponding alkene product after a low temperature quench. For the clean synthesis of dienes from the reaction, efficient zirconocene traps were discovered (chloroform and benzyl chloride), the former of which was used for the synthesis of a range of diene compounds. The traps were found to facilitate the decomplexation of zirconocene from zirconocene η2-alkene complexes which are formed after endocyclic cyclometallation of the benzyl-inserted zirconacycle. Finally, the novel reactivity of benzyl chloride with zirconocene η2-alkene complexes was explored, the scope of the reaction examined and mechanistic investigations undertaken. Ultimately the reaction allowed for the development of a novel one-pot three-component coupling reaction synthesising tri-substituted alkenes with a benzyl substituent. The reaction involved the insertion of alkenyl carbenoids into benzylzirconocene followed by transmetallation to zinc for addition of an aldehyde or for coupling with an aryl halide.

Internships or placements have increasingly been regarded as an essential component of hospitality education programs worldwide. These practice-based learning experiences benefit their stakeholders in ways that satisfy their interests, needs and increased expectations. This exploratory study investigates the perspectives of the primary stakeholders of an undergraduate hospitality management program at a Dutch higher education institution, namely, the student-interns, the institution's staff, and hospitality industry managers about what they consider as important for a successful internship practice. The study is constructivist in its overall approach and is underpinned by sociomaterial and practice-based learning perspectives, considering how issues of practices, relationships, and material aspects play a role in the work environment. It employs an exploratory case study comprising a preliminary survey and qualitative methodologies through documentary analysis of student-intern reports, and in-depth interviews some of which include field notes from visits to hosting organizations for student-interns. It was observed that the education of hospitality industry field around internships has not fully considered the way in which practices and learning are grounded in the social and material conditions which students face on placements. This study demonstrates that social and material dimensions of workplace learning do exert influences on how student-interns perceive and experience practices, on how they relate to others and on how they learn and shape their future perspectives. As it was observed, facing unstructured and ambiguous practices and artifacts, inadequate and inconvenient workspaces and being uncertain about their working environment and their future orientations, all triggered distinctive responses among interns. These responses were also influenced by their knowledge, skills and attitudes, previous experiences, their dual identity as students and employees, and the role of others both within and outside the hosting organizations. Moreover, merely facing inadequacies, ambiguity and uncertainty did not mean student-interns achieved learning; a supportive environment provided by supervisors, employees, and perhaps other interns at the hosting organizations and at the educational institution, were determinant in pointing out towards proactive responses rather than simply reflective responses, which then lead to learning on placement. Proactively taking responsibility and mobilizing others towards change, were integral to effective learning in helping to explain how students responded to perceived challenges. The study demonstrates that giving more attention to sociomaterial conditions in which practices are set, could contribute to enriching experiences and learning of students on placements; to potentially enhance hospitality education, and to assist hosting organizations with addressing staffing issues associated with retention and turnover. The study has direct implications for course revisions; career advice; collaborative synergies between the educational institution and the industry's firms; and informing best practices for the case institution and potentially for other institutions offering similar programs. The investigation ends with a formulation of recommendations for the three stakeholders of the program and suggests further research on internships considering the underlying theoretical frameworks for this investigation.

Students' socioemotional skills must be well developed and should be considered as a crucial component of education. Learning that occurs in an environment that enhances social context and develops socioemotional skills is an ideal environment to ensure readiness to succeed beyond the classroom walls. Multiage classrooms may prove to be a robust educational design in enhancing such learning. The purpose of this qualitative explanatory case study was to examine how the multiage classroom design affects instructional practices and students' socioemotional learning through social context. The researcher conducted interviews and observed multiage classrooms of four K-5 teachers in the northeastern United States to identify themes and patterns through their collective experiences. The problem addressed in this study is that the impact of multiage classroom design on student socioemotional learning and how the instructional practices found in this multifaced learning environment can be implemented appropriately in our current 21st-century classrooms needs to be further understood. While there has been an increased awareness of the importance of socioemotional development on student success over the last decade, the implementation of multiage classrooms has continued to decline. Implications of the findings suggest that through deliberate student-centered learning, grounded in social context, multiage classroom teachers become adaptive instructional experts and can facilitate higher-level learning in both affective and cognitive domains. The findings showed that the multiage classroom design impacts socioemotional learning in ways that are not always found in today's homogeneous classrooms. While the implementation of multiage classrooms does not come without challenges, these implications need to be further understood so that our schools today can continue to implement practices that best meet both the cognitive and socioemotional needs of students. [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.]

Two key challenges in modern statistical applications are the large amount of information recorded per individual, and the fact that such data are often not collected all at once but in batches, often causing distortions in both mean and variance. We address both issues by introducing a novel sparse latent factor regression model to integrate heterogeneous data. The model provides a tool that addresses data exploration via dimensionality reduction and corrects the so-called batch effects, and provides sparse low-rank covariance matrix estimates. We study the use of several sparse priors, both local and non-local, to learn the dimension of the latent factors. Our model is fitted in a deterministic fashion by means of an EM algorithm for which we derive closed-form updates; this contributes a novel scalable algorithm for non-local priors, which is of interest beyond the immediate scope of this thesis. We also present several examples, with a focus on bioinformatics applications. Our results mainly show an increase in the accuracy of low-dimensional data reconstructions, with non-local priors substantially improving the inference on factor cardinality and non-zero factor loadings. Moreover, thanks to our batch effect correction, we achieve a considerable improvement in recovering the latent factors. Altogether, this thesis provides a novel approach to latent factor regression that balances sparsity with sensitivity, as well as being highly computationally efficient, and opens new avenues for future research on dimension-reduction-based data integration. The methodology developed in this thesis is available in an R package at https://github.com/AleAviP/BFR.BE.

Despite the growing number of publications relating to three-dimension (3D) and education, the need for this technology, its usability and educational impact are not clear for dental education with the exception of haptics. The first stage of this doctoral research used a mixed method to examine key stakeholders’ views about those areas of dentistry that would benefit from having a 3D learning resource. Two hundred and five dental students, academics and graduates responded to the survey (134 females and 71 males). Results suggested that several areas of dentistry would benefit from 3D animations or simulations. Anatomy of the Temporomandibular joint (TMJ) was the top priority area from the list of the identified items. After identifying the areas of need, the researcher determined principles for e-learning and instructional design; followed by a feasibility study that identified a suitable authoring tool for the construction of a resource capable of containing 3D interactive models. A multidisciplinary team headed by the researcher developed the first iBook addressing the Tooth Morphology of the permanent dentition. The researcher collected feedback from users of the tooth morphology iBook using a mixed method experimental study, which included a questionnaire and a focus group session. Scottish and Chilean participants (n=138), from the University of Dundee and The Andes respectively, indicated that the iBook was well designed and it was a valuable resource where they could interact with the 3D models provided. These results informed the construction of a second iBook addressing the anatomy of the temporomandibular joint (TMJ) and masticatory system. Two versions of the TMJ iBook were created: a 3D version containing interactive models and a 2D version holding images. The researcher designed a comparative study including a pre-test/post-test intervention and a questionnaire to compare results from the two groups (3D and 2D). Twenty-seven first-year and thirty-two third-year dental students from the University of Dundee participated. The results of the intervention revealed statistically significant improvements in the results of first-years students who used the 3D version iBook compared to those who used the 2D one. The third-year cohort results revealed no significant difference between the 2D and 3D groups. The researcher arranged two focus group sessions to gain a deeper insight into the results. From those who took part in the intervention, eleven volunteered for the focus group sessions (six first years and five third-years). Results indicated that the TMJ iBook was a valuable resource for learning. Regardless the year of study, all participants preferred the use of the 3D interactive models as they had the potential to simplify visualisation and orientation, and enhance motivation for learning. Three key findings arose from this doctoral study. The first one indicates that several areas of dentistry would benefit from 3D resources and they would satisfy dental students’ needs. The second conclusion suggests that iBooks are a powerful, straightforward and valuable resource for creating new e-learning interactive material capable of displaying 3D models. The final finding suggests that the use of 3D interactive models have the potential to enhance learning in novice dental students, while they are capable of motivating and aiding visualisation both in junior and experienced students.

In a mobile robotic system, the interaction with the surrounding environment is essential in order to complete tasks such as localisation and mapping. This interaction can only be conducted by means of sensors that permit the accumulation of a large amount of information from several sources. However, this information is useless without adequate interpretation; thus, in order to accurately determine the positioning of the robot, it is necessary to identify and characterise landmarks in the environment required to serve as anchoring points for both localisation and mapping. Having constructed the map, an accurate analysis of the information gathered is vital. In this manner, this work is focused on two main aspects of any mobile robotic system: first, the detection and characterisation of highly descriptive landmarks by using image and point cloud processing techniques; and second, the geometrical and spatial analysis of the information gathered from the environment. For the former, two novel techniques based on image processing and geometrical analysis are presented; for the latter, a guaranteed technique for the parameter estimation of primitive shapes using interval analysis is proposed.

Research into the social behaviour of wild animals living in groups has demonstrated the importance of social structure dynamics and their consequences for an individual’s fitness. Many aspects of animal behaviour and ecology, including interactions with conspecifics, habitat use and willingness to take risks, can be a reflection of personality. One of the key concerns of captive animal husbandry is the social environment, as it is regularly modified and can shape the social behaviour of the animals in question in different ways. In this thesis I explore how meerkat, Suricata suricatta, social dynamics and individual positions may differ between wild and captive groups; I explore personality in the context of social networks and, lastly, I explore how physical and husbandry factors vary across enclosures and how this corresponds to a variation in the social structure of meerkats. Differences were found between the fifteen groups of captive meerkats when considering association networks based on foraging and resting. Some of these differences could be explained by intrinsic differences between the groups. An individual’s position within a network as described by their centrality and closeness measures could be predicted by their age and status, but rarely by their sex. I did not detect consistent patterns of non-random assortment amongst group members based on their sex, age or status. Groups of wild and captive meerkats differed in various aspects of their social network structure. Such differences may be due to individuals occupying different network positions and the difference in their number and strength of their connections to other individuals. This distinct way of interacting and associating could be a result of group specific attributes, such as group size, and/or the attributes of the donor and recipient, including sex, status or age. Critically, the differences may be explained by the dissimilar living environment that each encounters. The current results suggest that a meerkat social network in captive conditions can be less consistent than in their wild environment in the way they associate with one another, and in the manner they occupy particular positions in the network. Principal component analysis of the four personality traits revealed two personality dimensions, Friendliness and Aggressiveness, across the fifteen groups of meerkats. However, within a subset of my data (five groups), Friendliness was the only measure that robustly captured consistent individual differences across at least one year. A relationship was not found between attributes and personality dimensions due to age, status, and sex. Individuals with high Friendliness scores were more central in networks of foraging competitions. Aggressiveness did not explain an individual’s position in any form of interaction. There was no evidence that meerkats preferentially associated with or avoid others based on each of their personality scores. A relationship was found in the way animals associate with one another in the resting network based on the size and complexity of the enclosure and the type of shelter. Individuals were less likely to associate with others of the same sex or dominance status in enclosures that were larger or more complex. All the six external measures (the size and complexity of the enclosure, the type of barrier and day shelter, environmental enrichment frequency and human contact) influenced how individuals interacted with other group members within grooming, playing and dominance networks. In general, it seems to be that the key features to address in meerkat management in zoos are those of enclosure size and complexity (and perhaps provision of adequate shelters). Providing captive meerkats with more naturalistic and complex enclosures can help to preserve their natural social system.

Mean cell residence time (MCRT) is a major operational parameter in all biological treatment systems because of its relationship to growth rate and thus to metabolic activity. Due to their mode of operation, submerged anaerobic membrane bioreactors (SAnMBR) offer a homogenous system in which MCRT can be simply controlled through volumetric wastage. Although a number of studies using SAnMBR have been reported, however, little information is available regarding the effect of MCRT on operational performance, mixed liquor characteristics and the influence of these on membrane performance. In this research an innovative SAnMBR using gravity-induced transmembrane pressure to maintain flux was developed and tested for first time. This configuration was then used to evaluate the impact of MCRT on membrane flux, mixed liquor characteristics and overall performance of SAnMBR treating low-to-intermediate strength wastewater. Long-term experimental periods of more than 240 days allowed steady-state conditions under different MCRTs, in which the mixed liquor suspended solids (MLSS) adjusted to the applied load, making possible to assess the influence of this growth and metabolism-dependent kinetic parameter. The SAnMBRs were monitored for membrane flux, overall process efficiency and mixed liquor characteristics when operating at 36 oC and 20 oC. The results of this work showed that at both operational temperatures, the MCRT has a significant effect on the mixed liquor characteristics, particularly on the filterability which was higher at short MCRTs. This resulted in improved membrane flux at relatively short MCRT, although no advantages were observed if the MCRT was further reduced. Higher specific methane production was observed at longer MCRT, most probably due to a higher fraction of carbon incorporated into biomass as a result of higher microbial growth rates. Overall, the results of this research showed that the MCRT has a considerable effect on the mixed liquor characteristics and thus on the membrane fouling and overall reactor performance. It is clear that there is a trade-off to be made between enhanced membrane performance, specific methane production and sludge yield when considering the most suitable operational MCRT. Further studies are required to identify the optimum MCRT for a wider range of wastewater and other operational parameters and to fully understand the causes of these effects.

Background: Dengue is the second most important vector-borne disease in tropical regions largely affecting urban areas. Rural-urban migration increases numbers at risk. In particular, Internally Displaced Populations (IDPs) are forced to migrate through violence, conflict, or natural disasters moving to informal settlements in urban areas. IDPs might represent a pool of susceptible and vulnerable people; because of their cultural, socio-economic, and demographic factors that differ from the local people. Colombia has the third highest number of dengue cases in the Americas and the second largest IDPs number in the world. Aim: To examine the relationship between IDPs and Dengue in Colombia. Methods: A mixed methods approach was used including: policy and literature review; analysis of routinely available national-level data sources; quantitative household surveys of knowledge, attitudes, practices and vector counts in IDPs and host population households; focus group interviews with IDPs and host populations, and interviews with public health authorities and those working with IDPs. Results: A range of policies addresses both dengue and IDPs in Colombia but there is no policy addressing both issues. Analyses of national level data showed that areas with high level of IDPs tended to have high levels of dengue. Household surveys showed that despite IDPs being more economically disadvantaged and having less access to education and health services, knowledge, attitudes, and practices were broadly similar, although IDPs households were more likely to obtain their information from community networking. IDPs households were more likely than host populations to have productive breeding sites for the vector in their households despite emptying and cleaning water containers more frequently. Participants were aware of dengue, but had mistaken knowledge about disease severity, treatment, transmission and effective control measures. Conclusions: Dengue control in IDPs can be strengthened through community networking and integrated policies to increase access to health and education services.

The bioelectronics field has incorporated an increasing variety of conducting polymers in applications that involve mixed ionic/electronic transport, yet there is still a lack of design rules to purposefully tune the electronic and ionic contributions to a material's conductivity, as well as processing methods to further control and understand their interplay. New undoped co-polymers were explored as electroactive materials in aqueous media. The range of materials allowed establishing a simple design rule with potential to be explored in other model semiconductors. The most hydrophilic system showed promising response when benchmarked with poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) in order to be employed in new operation modes of devices which rely on the electrochemical doping of the active layer, such as organic electrochemical transistors (OECTs). The capabilities of the most promising system were further exploited as an ion-to-electron converter by creating multicomponent systems that included a polar insulator to tune their ionic transport. The straight-forward and chemically inert blending approach showed enhanced transport of ionic species while maintaining their electronic transport as well as displaying characteristic response times linked to the presence of the polar phase. By using the semiconductor as a model system and controlling the volume of aggregates present in the solid-state by means of processing, a phenomenological description was given of ionic transport in different regions of semicrystalline polymers along with their associated decay rates. Finally, the effect of humidity in the charge transport of the undoped co-polymers was explored, with a focus on elucidating ionic contributions from electronic ones. The incorporation of a ionic conductor, Nafion, in a bilayer structure was explored and showed an intimate interaction between the proton conductor and the electronic conductor. The potential of the multilayer structures as humidity sensors and other remarkable features found in their charge transport make these promising systems for further applications in bioelectronics.

Over the last decade, the global struggles of indigenous peoples have become ever more visible. The thesis draws connections stemming from the ongoing existence and challenges of the Maya people of Yucatán in Mexico, not to the evident resistance of ongoing indigenous movements in the Americas, but to their endurance. Here, I examine the multiplicity of events occurring in the Maya solar of Yucatán, a house and garden plot that has historically supported an intricate indigenous system of land, livelihoods and identities. The solar is today under threat of extinction along with the way of life and the people it once fully sustained. This threat is itself a contested terrain as the current and historical endurance of the solar and of Maya peoples may be proof of their resilience. This thesis focuses on the unfolding transformations of the solar and the responses of Maya populations, gathered in Yucatán at different points between November 2013 and May 2015. Based on qualitative research that combines interviews and secondary documentary analysis, the research seeks to recognise and validate the human experience and situated knowledge of Maya populations. The data collected is interpreted through an overarching theoretical and methodological framework drawn from the Decoloniality perspective, which addresses the continuation of colonial powers within the modern world and highlights the historical denial of power, knowledge and being to native societies under the long-term effects of ‘coloniality’. Through the Decoloniality perspective, I contest and rework existing theoretical frameworks of ‘Primitive Accumulation’, ‘Latin American urban studies’, and ‘Indigenous Geographies’ in order to foreground indigenous and colonial questions from a political and epistemological Latin American perspective. Extensively, this research: 1) provides new evidence of the Maya’s plight, bringing to light their realities and their everyday life; 2) decolonises knowledge through further developing the Decoloniality perspective; and, 3) challenges the general understandings of Maya populations as a far more complex and contradictory than their usual dichotomous representation: as urban/rural, modern/traditional and indigenous/non-indigenous.

Schizophrenia is a severe psychiatric disorder that affects more than twenty-one million people worldwide, contributing significantly to the global burden of disease. A growing body of genetic, epigenetic and epidemiological evidence suggests that schizophrenia has its origins during neurodevelopment and that dysregulation of the immune system and infection may play a role in disease etiology. Twin and family studies have highlighted a considerable heritable component to schizophrenia; however the role of genetic variation in the etiology of the disorder is complex. In the majority of cases, susceptibility is attributed to the combined action of multiple common genetic risk variants of low penetrance. Improved understanding about the biology of the genome has led to increased interest in the role of non-sequence-based variation in the etiology of neurodevelopmental phenotypes, including schizophrenia. The notion that epigenetic processes and gene expression dysregulation are involved in the onset of schizophrenia is supported by recent studies of disease-discordant monozygotic twins, clinical sample cohorts, and post-mortem brain tissue. To date, however, studies characterizing schizophrenia-associated methylomic and transcriptomic variation in the brain have been limited by small sample number or the assessment of a single brain region. The main aim of this thesis was to undertake a comprehensive study of genomic variation across four brain regions in schizophrenia. The results provide further support for a neurodevelopmental origin to schizophrenia, as well as a role of the immune system on schizophrenia etiology. My analyses also suggest that epigenetic variation associated with polygenic burden for schizophrenia might play a role in the disease. In summary, the work presented in this thesis represents the first analysis of epigenetic and gene expression variation associated with schizophrenia across multiple brain regions and highlights the utility of polygenic risk scores for identifying molecular pathways associated with etiological variation in complex disease.

Iron Age coastal communities in England have been poorly understood since the beginning of our discipline. This is mainly as result of the lack of evidence for everyday maritime activities and also the focus of research on explaining an agro-pastoral way of living. Evidence of fishing, boats, harbour structures and ports are very rare archaeologically, and thinking about people living by the sea in this period has been widely overlooked as most of the interest has been the nature of the connections and trade-networks (mainly by Cunliffe 2008). In contrast, evidence for non maritime activities, such as farming and cattle rearing is so rich that looking to the coast only happens in special situations. Using the Isles of Scilly as a case study, this research challenges the established views that societies on the coasts of south-west of England were mainly cattle herders and farmers. Through palaeolandscape reconstruction, site analysis and material culture study, this research argues that settlement on the coastline is as important as that found inland. It shows that Iron Age maritime aspects of culture were deeply embedded within cultural traditions and that the maritime way of living had little to do with extraordinary or unusual situations. This research shows that preconceived ideas of what a maritime site should look like, as is the case of harbour structures and important ports, divert the attention from the subtleties of recognising maritime culture’s signature. It is through the study of archaeological context and environmental evidence that these are likely to become more obvious. Therefore, throughout this document the analysis of maritime landscape, settlement pattern and material culture generates new perspectives on how to approach the study of maritime societies in archaeology.

Lameness is a detrimental problem for the welfare of cows and farmer profits; it causes changes in cow behaviour, which have direct impact on milk production as cows reduce their overall activity. The main aim of this thesis was to investigate behavioural changes caused by lameness and lameness treatment in cows housed in automatic milking systems; in addition it aimed to investigate the effect of claw horn lesions on the likelihood of recovery from lameness. The effect of lameness on dairy cows visits to an automatic milking system was investigated using a case-control study. It was observed that lame cows visited the automatic milking system less in comparison to non-lame cows in particular between 00:00 and 05:59. The effect of lameness on rumination time was investigated in a longitudinal study. Results showed that lame cows ruminated 8 minutes/day less than non-lame cows. The effect of lameness treatment on dairy cow behaviour was investigated in a randomised clinical trial. Newly lame cows were randomly allocated to one of four treatments; these cows were matched to non-lame control cows. Cows treated with a therapeutic trim and a foot block increased their lying time in the five days after treatment in comparison to non-lame cows. The increase in lying was distributed throughout the day. None of the treatments caused changes in the number of milking visits per day after treatment. Lame cows treated with trim and NSAID showed a reduction in their rumination time (-59 minutes/day) during the 5 days after treatment in comparison to non-lame cows. The effect of claw horn lesion type on the likelihood of recovery from lameness was investigated using photographs taken before lameness hoof trimming was applied. The results showed that cows with white line haemorrhage and those that were more severely lame at the time of treatment were less likely to recover at 2 weeks after hoof trimming was applied. In addition, recovery was positively associated with the size of the white line haemorrhage. The present thesis demonstrated that lameness and lameness treatment affected cow behaviour, and may delay recovery. Early recognition and prompt intervention should be encouraged in order to reduce the behavioural changes caused by lameness and improve the recovery rates from disease.

To promote a change in epistemic beliefs in in-service university teachers and a consequent improvement of their teaching methods to encourage students to take a more sophisticated approach to learning their subjects, I explored the relationships between epistemic beliefs and approaches to teaching in a group of 111 lecturers across different disciplines at the University, Colombia, South America. This correlational research is based on epistemic metacognition research (Hofer & Pintrich, 1997) and phenomenography research (Marton & Booth, 1997). The methodology comprised quantitative and qualitative research techniques including the participation of a selected sample in face-to-face and online interventions. I also conducted two questionnaires, the Discipline-Focused Epistemic Beliefs Questionnaire (DEBQ) (Hofer, 2000) and the Approaches to Teaching Inventory (ATI) (Trigwell & Prosser, 2004). Furthermore, I carried out interviews that were later analysed according to phenomenographic principles. Based on the findings, I concluded that the DEBQ and the ATI are suitable in measuring epistemic belief and approaches to teaching in a university setting. As I found correlations between epistemic beliefs and approaches to teaching, I concluded that epistemic beliefs do play an important role and influence the way in which teachers approach their own teaching. Additionally, as there was a statistically significant decrease in the Information Transmission/Teacher-Focused Approach through the online intervention, and as epistemic beliefs and approaches to teaching are correlated, the results indicate the possibility of a change from naive to more sophisticated epistemic beliefs. The results also indicate the possibility of changing epistemic beliefs and approaches to teaching through an online intervention or facilitated by online learning environments. The results also indicate the possibility of changing approaches to teaching through short-term interventions as well. Regarding disciplinary differences, lecturers did have different perceptions. I concluded that discipline did have an influence and an impact on epistemic beliefs and approaches to teaching. There was no statistically significant difference between genders or the number of years of experience. Finally, there were variations in lecturers‘ ways of experience learning, teaching, Information and Communication Technologies (ICTs), and knowledge. The description of lecturers' experiences of learning, teaching, ICTs, and knowledge shows 13 qualitatively distinct categories of descriptions. Also 13 holistic views, in a form of outcome space, were derived from their various ways of experiencing those phenomena.

A statistical framework for spatiotemporal modelling should ideally be able to assimilate different types of data from different of sources. Gaussian processes are commonly used tool for interpolating values across time and space domains. In this thesis we work on extending the Gaussian processes framework to deal with diverse noise model assumptions. We present a model based on a hybrid approach that combines some of the features of the discriminative and generative perspectives, allowing continuous dimensionality reduction of hybrid discrete-continuous data, discriminative classification with missing inputs and manifold learning informed by class labels. We present an application of malaria density modelling across Uganda using administrative records. This disease represents a threat for approximately 3.3 billion people around the globe. The analysis of malaria based on the records available faces two main complications: noise induced by a highly variable rate of reporting health facilities; and lack of comparability across time, due to changes in districts delimitation. We define a Gaussian process model able to assimilate this features in the data and provide an insight on the generating process behind the records. Finally, a method to monitor malaria case-counts is proposed. We use vector-valued covariance kernels to analyze the time series components individually. The short term variations of the infection are divided into four cyclical phases. The graphical tool provided can help quick response planning and resources allocation.

Having worked as a psychologist in both the UK and Lima, Peru, working with patients who present a variety of conditions ranging from a depression to severe cases of schizophrenia, I became concerned by the way in which patients reacted to their diagnoses and in particular by the negative response of patients diagnosed with Borderline Personality Disorder (BPD). I also perceived that the lack of a clear and accepted diagnosis caused significant confusion regarding the condition for patients, carers and professionals. This led me to question the value of the diagnoses in the process of understanding and helping people with emotional distress or psychological problems. This study is a response to my experience and the experience participants expressed through me.

Graft versus Host Disease (GvHD) remains one of the main complications after haematopoietic stem cell transplantation (HSCT). Due to their ability to suppress effector cells, CD4+CD25highFoxp3high regulatory T (Treg) cells have been proposed as a cellular therapy to prevent GvHD. However it has been shown that Treg cells can inhibit natural killer (NK) cell functions. NK cells are key effectors of the Graft versus Leukaemia (GvL) effect post-transplant; therefore, it is plausible that a Treg cell therapy may impact on NK cell function and differentiation from haematopoietic stem cells (HSC). This study sought to elucidate the effects of Treg cells on NK cell function and differentiation using umbilical cord blood (CB) as a cell source. Herein, it is confirmed that CB CD4+CD25highFoxp3high Treg cells are fully functional and upon TCR-stimulation express CTLA-4 and LAP, and secrete TGF-β and IL-10. Also, they express receptors associated with trafficking to lymphoid tissues and the bone marrow, which are potential NK cell/Treg cell interaction sites. Furthermore, it is shown that CB Treg cells can suppress CB NK cell functions after TCR-stimulation in steady state but not in the presence of exogenous cytokines. Lastly, in an in vitro model of NK cell differentiation, a 90% reduction in total NK cells was observed when TCR-stimulated Treg cells were added at the time when HSC commitment to the NK cell lineage occurs. Interestingly, the few NK cells that developed in these cultures showed normal phenotype, IFN-γ secretion and cytotoxicity. Notably, the addition of human recombinant TGF-β to HSC cultures caused a similar reduction in NK cell differentiation as shown when TCRstimulated Treg cells were added to HSC cultures. Moreover, the Treg cellmediated effect was contact-dependent and cytokine competition-independent. Collectively, these results demonstrate for the first time that TCR-stimulated CB Treg cells inhibit NK cell differentiation through TGF-β, providing information for optimisation of the time of delivery for an adoptive Treg cell therapy post-HSCT to prevent GvHD.

Brazil and England are an ocean apart and their legal systems are very different. Nevertheless, when it comes to the practice of arbitration, after many years, Brazil adopted an irreversible pro-arbitration environment while England has been an arbitration friendly forum for more than a century. When the use of arbitration grows, inevitably, the question of what disputes can be submitted to arbitration will be raised. The natural tendency is to expand the range of disputes, but this could not be understood as a rule, there will always be a limit. Even though arbitration in Brazil and England are not on the same level of sophistication, courts in both nations have been making decisions regarding issues of arbitrability. The question of what matters can be submitted to arbitration is not seen in the same way around the globe; however, hopes and engagements towards uniformity have been welcomed by the international community. This thesis examines the issue of arbitrability through a comparative study between the English and the Brazilian legal system. The scope of the research is to assess if looking at the two countries, one a stable economy with a tradition of arbitration and the other an emerging economy where arbitration has grown expansively over the past ten years, is feasible to seek alternatives on a possible harmonisation. In order to achieve the thesis' goal, the research fIrst provides for a deep examination of what arbitrability is and its implications. After such scrutiny, the comparative study is done by making an analysis of the current Arbitration Acts in England and Brazil, demonstrating how they approach the issue of arbitrability and how the case law concerning the issue of arbitrability compares. The comparative research is done by looking at the functional equivalence that arbitrability has in both legal systems to see in which direction the two nations are going and if they are approaching or distancing themselves from in the international view of arbitrability. The results verify what can be extracted from the English system to be implanted in the Brazilian system and vice-versa. Through this examination, utilising England and Brazil as case studies, the conclusion asserts if there are alternatives leading toward harmonisation or if such an attempt should be excluded from international policies in arbitration.

In this thesis we describe experimental studies carried out in three different granular systems. Firstly, we describe the results of experiments and computer simulations carried out to test the validity of a randomly-forced model to describe the behaviour of a vertically vibrated, granular monolayer. We study how a single particle moves across a vibrated roughened surface and show that both a random force and viscous dissipation are needed to match the experimental data. We then simulate a collection of particles driven in this way and compare the structure factor S(k) obtained from simulation with that measured experimentally. The small k behaviour of S(k) reveals a quasi long-range structure which has not been observed previously. Secondly, we study the behaviour of water-immersed granular beds. The first system consisted of spherical barium titanate particles contained in a rectangular cell which is divided into two columns, linked by two connecting holes, one at the top and one at the bottom of the cell. Under vibration the grains spontaneously move into just one of the columns via a gradual transfer of grains through the connecting hole at the base of the cell. We have developed numerical simulations that are able to reproduce this behaviour and provide detailed information on the instability mechanism. We use this knowledge to propose a simple analytical model for this fluid-driven partition instability based on two coupled granular beds vibrated within an incompressible fluid. In the second system to be studied a water-enhanced Brazil nut effect, which occurs when the vibrated granular bed is fully immersed in a liquid, will be describe. We use a bed of glass beads immersed in water and monitor the behaviour of a large steel intruder as the system is vibrated vertically. To aid our understanding, we have developed numerical simulations to model this system and provide detailed information about the fluid and grain motion. The mechanism responsible for the rapid rise of the intruder is shown to be fluid-enhanced ratcheting rather than simple differential drag. Lastly, we describe experiments carried out in a levitation magnet to investigate the behaviour of spheres suspended magnetically in a viscous fluid. Under vibration the spheres attract and for sufficiently large vibration amplitudes the spheres are observed to spontaneously orbit each other. Data collapse shows that the instability occurs at a critical value of the streaming Reynolds number. Simulations are used to provide a detailed understanding of the cause of this instability.

This study addresses site-specific sculptural practice and examines the tensions arising from the interactive relations between site and the artworks that exist within it. It applies the concept of ‘anthropophagy’ to re-signify traditional models of representation in order to re-organize them into new contexts through practice-led research into site-specificity. Anthropophagy, a metaphorical vision of the Brazilian indigenous people, utilises cannibalistic customs “in order to legitimate their critical, selective and metabolising appropriation of European artistic tendencies” (Mosqueira 2010: 12). The use of this concept in this thesis arises from the idea of simultaneously belonging to two geographically separated cultural universes: one individual (in my case, Brazilian) and another related to the centralised European/US cultural model of influence that dominates the art world. The differences and intersections between these two universes provide a rich field for practice-led research into how artistic creation is affected by attitudes to space and time. In order to explore this, the thesis is divided into four chapters. The first develops a theoretical framework dealing with concepts of space and time and demonstrates how anthropophagy draws these concepts together. The next chapter examines walking in the UK as an art practice to expand the understanding of site-specific practice through the artworks of Richard Long and Hamish Fulton. The third chapter focuses on work, site and location in order to examine how anthropophagy can re-signify the idea of walking as related in Chapter two. The final chapter analyses site-specificity, drawing on my own practice-led research explored through three art projects implemented in Brazil and England. These projects develop ways to negotiate the complex relationship between art, place and temporal contexts, re-inscribing events within specific sites over time. To build a methodology for the research, I have developed three different projects and situations testing the spatial-temporal contexts of site. By using site-specific art practice I shape my arguments upon a creative practice ruled by concepts, materials and techniques. In my practice I have delineated some creative responses to the transformations of the contemporary world, weaving iii reflections between work/site/body as well as on my own perception regarding current ‘temporalities’. The theoretical frameworks that inform this study range from postmodernism to globalisation theories in order to draw together work, site and location under the overarching concept of anthropophagy.

Modern IT systems are continuously growing both in size and complexity, thus making performance analysis and modelling an increasingly difficult task, if not intractable. As a result, in some cases the task has to be significantly simplified by focusing on selected system components or by reducing it to a smaller scale. One of the biggest challenges in system performance modelling is the accurate determination of service requirements. This thesis presents an investigation into novel statistical inference methods to effectively parameterise queueing models from system traces which exhibit diverse characteristics. I present two case studies, namely one of an Enterprise Resource Planning (ERP) application and one of a web server. Firstly, I propose a modelling methodology to address the limitations of service demand estimation based on CPU utilisation measurements by directly calibrating queueing models based on response time measurements. Secondly, with the aim of capturing more representative web workloads, I propose a methodology to parameterise queueing models for web server performance analysis that extracts hidden Markov models from real HTTP traffic via fitting. Experimental results indicate that all the methods developed as part of this thesis are highly competitive against state-of-the-art techniques.

Literacy rates among male adolescents continue to fall below those of female adolescents, and this trend shows no indication of improving (Cheung & Slavin, 2014; Gurian & Stevens, 2007; Weins, 2005; Clark, 2006; Cantrell & Carter, 2009). This study aims to examine this trend by measuring the effects of extended literacy learning opportunities and multimodal learning opportunities on comprehension and vocabulary attainment in low-achieving adolescent male readers. Post hoc Nelson-Denny Reading Test (NDRT) data were collected over a 5 year period (2010-2016). Participants were 95 (N=95) male adolescent students entering their freshman year of high school who scored below the 16th percentile on the High School Placement Test (HSPT) in reading, verbal, and language and were placed in specific reading classes that provided extended literacy learning opportunities for additional remediation. All participants in the study were given both a pre- and post-NDRT (forms G & H) to determine comprehension and vocabulary growth over the course of each indicated school year. The participants were separated into pre-iPad (2010-2012) and iPad (2012-2013 and 2014-2016) implementation groups for NDRT data analysis. The pre- and post-NDRT data were analyzed using nine paired-samples "t"-tests to measure growth between pre-iPad and iPad groups as well as to measure the combined growth of both groups. The data that were analyzed using paired-samples "t" tests resulted in the rejection of all of the null hypotheses. The findings indicate that a statistically significant difference in vocabulary and comprehension achievement (p < 0.05) was found when low-achieving adolescent male readers were provided with extended literacy learning opportunities. The findings also indicate that a statistically significant difference in vocabulary and comprehension achievement (p < 0.05) was found when low-achieving adolescent male readers were provided with multimodal learning opportunities via the iPad during literacy instruction. The findings further indicate that a statistically significant difference in vocabulary and comprehension (p < 0.05) was achieved by the program as a whole. Additionally, independent sample "t"-tests were used to analyze the difference in comprehension and vocabulary gains between the pre-iPad and iPad groups. The findings indicate a statistically significant difference in comprehension gains between the pre-iPad and iPad groups, with the pre-iPad group demonstrating greater gains. The findings further indicate that there was no statistically significant difference between vocabulary gains in the pre-iPad and iPad groups. Hattie (2012) determined that the effect size for computer-assisted instruction can be measured at 0.37, which is a medium effect size. This indicates that those who receive computer-assisted instruction could be expected to perform better than 66% of those who do not receive computer-assisted instruction. Hattie also determined that the web-based learning effect size is measured at 0.18, a small effect size (as cited in Fisher et al., 2016). When effect sizes were compared to the overall effect size of this study's iPad group, it was determined that the iPad group, with an overall effect size of 0.91, showed growth that would be greater than 82% of those not receiving the treatment of the iPad for literacy instruction (Coe, 2002). The use of the iPad for instruction exceeded expectations for both computer-based instruction and web-based learning in both vocabulary and comprehension. There are many implications of the findings of this study. There is limited research available regarding the use of the iPad as a means of mitigating literacy deficits in adolescents. This is one of very few studies that has focused on the use of the iPad as a tool for literacy instruction for low-achieving adolescent male readers, and the sample size of this study is relatively small (N=95). Since the iPad has only been available as a tool for classroom instruction for a short period of time, more research needs to be done to determine the overall effectiveness of iPad based instruction for low-achieving adolescent male readers, a group that it appears could benefit substantially from its use if the right circumstances emerge. [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.]

In this study, 24 adults without any psychological or neurological disorders participated either in 10 neurofeedback training sessions to increase the amplitude of a frequency band between 12 and 15 Hz (sensorimotor rhythm - SMR) or in ten mock neurofeedback sessions. Pre and post training measures of memory and executive functions were completed, along with quantitative electroencephalography (QEEG) measurements in order to detect changes after the training course. Furthermore, measures of SMR amplitude were taken within and across sessions to determine whether self-regulation of SMR had been achieved. The data analysis performed shows no significant differences in cognitive performance between the group who underwent neurofeedback training and the group who underwent mock neurofeedback training. The groups did not show electrophysiological changes after the training. Additionally, no significant changes in SMR amplitude or percent time above threshold across or within the 10 sessions were found in the experimental group. Moreover, the data showed a tendency, which indicates that the higher the baseline amplitude and absolute power of SMR the less time was spent above threshold during the training and the less increase in SMR amplitude between baseline and training periods. The findings obtained indicate that neurofeedback training did not affect memory, executive functions or the QEEG. The absence of significant changes in SMR amplitude across sessions might reflect failure in learning the neurofeedback task and may account for the lack of cognitive improvement and QEEG changes. The fact that the ability to self-regulate SMR might be dependent on baseline amplitude has important implications in setting thresholds. Setting thresholds according to baseline levels might increase the difficulty in maintaining SMR above threshold when the baseline is higher. Future research should also address whether baseline amplitude has a predictive value in determining successful self-regulation of brain activity.

In recent years, the relationship of gut hormones and adipocytokines with bone processes has received increased attention. It represents one aspect of the current skeletal investigation. The understanding of these interactions between bone metabolism and gastrointestinal or adipose tissue function must take into account homeostasis, appetite, neural system, and lifestyle. The proportion of bone mass to soft tissue is a relationship that seems to be controlled by delicate and subtle regulations that imply "cross-talks" between the nutrient intake and tissues like fat. Thus, recognition of the mechanisms that integrate a gastrointestinal-fat-bone axis and its application to a number of aspects of human health is vital for improving treatments related to bone diseases. This thesis analysed some of the aspects of experimental research regarding the effects of gut hormones and adiponectin when they were present in cell cultures of osteoblastic cell lines. mRNA expression levels of five gut hormone receptors were analysed in three osteoblastic cell lines (Saos-2, TE-85 and MG-63) using molecular biology techniques (reverse transcription and real time polymerase chain reaction, RT-qPCR). The gut hormone receptor mRNA expression was positive for GIPr, GHSr and GPR39 in the three cell lines whereas GLP-I r and GLP-2r were only expressed in the least mature cell lines (MG-63 and TE-8S). The responses to the gut peptides were studied finding significant changes in viability, and biochemical bone markers like alkaline phosphatase (ALP), procollagen type 1 amino-terminal propeptides (P 1NP), and osteocalcin production. Other experiments included the study of induction of e-fos in presence or absence of extracellular nucleotides using a luciferase assay and RT-qPCR. Adiponectin receptors and effects were investigated in one of the osteoblastic cell lines, Saos-2, finding the presence of the receptors in these cells. Functional studies revealed that adiponectin caused significant changes in viability, ALP and PI NP production. Significant changes were also observed in osteoprotegerin expression. The adiponectin receptors were additionally investigated in peripheral blood mononuclear cell (PBMC) cultures since they are the precursor for osteoclasts. The experiments were carried out in the presence or absence of cytokines (M-CSF, RANKL) which stimulate PBMC to commit to differentiation to osteoclastic cells. The levels of AdipoRI were higher than AdipoR2 when evaluated by qPCR. Immunofluorescence using anti-AdipoR 1 and -AdipoR2, displayed specific green emission in foci located mainly in the periphery of the cells but also in the cytosol in cells that were cultured up to 21 days with M-CSF and RANKL. These observations in immunofluorescence suggest that the adiponectin receptor could be undergoing redistribution in the osteoclastic cells. Taking together all the results it is enticing to speculate that the distribution of bone and soft masses is regulated by the direct effects of the hormones involved in the absorption of nutrients (gut hormones) and those produced in soft tissues like fat, as in the case of adiponectin.

Protectionism or retaliation is often argued as the motivation for the increasing use of anti-dumping measures by developing countries. In this research, I address other possible motives for the relentless use of these measures, such as collusion and trade deterrence. The main hypothesis is that price distortions generated by the introduction of anti-dumping policy serve as a departure point for the achievement of the collusive agreement. I develop a theoretical model in which a duopoly compete infinitely à la Bertrand in the importing market and anti-dumping policy serves as a mean to enforce and sustain the collusive outcome. Econometric analysis is performed in order to measure the impact of anti-dumping measures in the Mexican economy. Using a rich panel data of imports I investigate the trade restriction effects of anti-dumping, i.e. trade destruction and trade diversion. Testing for trade harassment effect is also achieved. In depth analysis of the debate between competition policy and anti-dumping policy reform is developed and some recommendations on the application of the competition policy framework are pursed in order to tackle the discriminatory use of the antidumping regime. It considers, however, the need of such an instrument in an environment where production in some sectors is characterized by advantageous conditions that can harm local industries. The research contributes to the literature on antidumping from a developing country point of view and is one of the few works that look in to the effects of antidumping policy in Mexico and puts emphasis on the domestic market structure of the petitioning country.

The aim of this research is to investigate and analyse how narrative poems and sonnets, two types of traditional poetry, have been handled in books, in England, in terms of typographic presentation. It focuses on how far the earliest printed editions of a poem establish a pattern for its subsequent presentation, and how far other influences might determine the typographic form. The main focus of the analysis is segmentation, the visible division of the text into units which, to a greater or lesser extent, reflect its underlying structure. This division is seen through methods of segmentation in the opening and closing of the poem and, within the poem itself, through typographic features such as indentation, capitalization, line spaces and the placing of each poetic line on a new typographic line. These methods are related to the poetic whole, stanzas. rhyme scheme units, verse paragraphs and line.

The process of generation, transmission and distribution of electric energy appears to be very simple. However, the continuous flow of power through electric networks is affected by several factors, normally of two kinds: failures caused by ageing of insulating materials and failures caused by defective equipment or design. The energy supplied to small and big consumers can be interrupted for long periods causing disastrous economic losses. The origin of most failures normally is found in electrical insulation, which is an essential component in all electrical systems especially in power equipment such as transformers and circuit breakers, the cost of which is very high. Before the insulation fails, there are manifestations of this condition, called partial discharges (PD) and because of this, PD have been subject of an extensive study and investigation. PD identification relies on the intrinsic characteristics of the generated discharge. This thesis shows the behaviour of radiated discharge through the analysis of the characteristic frequency spectra and pulse distribution to create pattern classification in the laboratory. This research is based on a novel technique that uses wide band, high resolution equipment, composed of an antenna array, that receives the radiated discharge, and a high resolution oscilloscope that accurately measures and samples the propagated signal. The second part of the laboratory setup comprises the characterization of partial discharges using a high voltage transformer and measurement devices that accurately apply a range of voltages to specimens containing insulation defects. The advantages of having accurate PD sources are evident: availability, free of ambiance noise, accurate AC reference and PD location. Results show that pattern recognition to identify PD'S using a non invasive system and point on wave information is possible and reliable.

The main objective of this thesis was to estimate the sensitivity and specificity of four screening tests: visual inspection after the application of acetic acid (VIA), VIA_M: combined VIA and VIAM (magnified VIA using an AviScope performed by a doctor), liquid-based cytology (LBC using the AutoCyte-Prep manual system) and HPV testing (using Hybrid Capture II); to detect histologically confirmed high-grade squamous intra- epithelial lesions (HSIL). Participants of the "Tamizaje y Tratamiento Inmediato de lesiones cervico-uterinas" (TATI) project, who signed an informed consent for additional cervical samples, were included in this study. Separate cervical samples for conventional cytology (CC), LBC and Hybrid Capture II (HC-II), were collected by a midwife before applying acetic acid (5%) to the cervix and performing VIA. Women testing positive on VIA were referred to VIAM performed by a doctor who confirmed the midwife diagnosis, and treated lesions with cryotherapy if appropriate, or referred women to colposcopy. Negative women on VIA_M; underwent colposcopy if they had HSIL on CC or LBC; or had second screening if they had any lesser abnormality on LBC or were positive only on HC-II. Of 5565 participants, 104 had histologically confirmed HSIL and an estimated 112 had undetected/unconfirmed HSIL. Sensitivities of VIA, VIA_M, LBC (any abnormality), LBC (high-grade abnormality) and HC-II were 44% (95% confidence interval (CI): 34,59), 31% (CI: 20,50), 69% (CI: 61,78), 35% (CI: 23,56) and 72% (CI: 65,79), respectively. VIA had the lowest specificity among all tests: 77% (CI: 74,77). LBC ?HSIL had the highest PPV: 44% (CI: 34,53). HC-II was more sensitive than the other tests in our study. LBC ?HSIL was more specific than the other tests. VIA had low sensitivity and specificity. VIA could still be an option for developing countries if implemented with regular quality assurance.

Primary open angle glaucoma is a progressive and relatively common disease. Damage to the retinal ganglion cells causes characteristic structural changes in the optic nerve head, progressive loss of visual function and eventually blindness. Early detection of this disease is therefore desirable. It has been suggested that the assessment of impaired visual function in glaucoma can be made more sensitive by the selective isolation of specific stimulus attributes. An important aim of this investigation was to establish how the processing of colour or luminance contrast signals is affected differently in glaucoma. Chromatic sensitivity was measured using a computerised colour display that employs isoluminant colour-defined stimuli buried in dynamic luminance contrast noise, stimulus conditions that isolate the use of colour signals and reveal loss of chromatic sensitivity. The characterisation of chromatic sensitivity loss in a group of POAG and at risk subjects was determined by measuring chromatic displacement (CD) thresholds along 12 directions in CIE - xy chromaticity chart, which allowed fitting CD ellipses. The analysis of the pattern of CD loss at different stages of the disease, both at the fovea and 7 deg, reveals the earliest signs of damage to be found at the paracentral location (7 deg). A non-selective CD loss with a characteristic increase in variance is observed early in the disease. As damage progresses foveal sensitivity is also progressively affected showing a greater B/Y relative loss, which becomes similar and even exceeded by the R/G loss when the disease is established. For moderate and advanced stages of the disease, the relative loss becomes greater for the R/G thresholds at both foveal and 7 deg. The test showed an overall success rate of 71% in identifying cases correctly. In addition, moving, colour-defined stimuli designed to isolate either the transient luminance channel or the R/G and B/Y chromatic colour opponent mechanisms were used to find evidence of preferential damage for detection of one or the other of these stimulus attributes. Findings in patients with POAG and normal subjects of similar and younger age were compared. The relative increase of chromatic (R/G and B/Y) and achromatic thresholds was determined with ageing and glaucomatous damage. Although both mechanisms were significantly affected by POAG damage, the chromatic thresholds showed greater relative increase. The R/G and B/Y chromatic thresholds increased differently as a function of the severity of visual field loss. The B/Y sensitivity showed the greatest loss in early glaucoma subjects, however the R/G mechanism showed a faster rate of threshold increase and a better correlation with severity of field loss than B/Y thresholds. Ageing affected significantly both the chromatic (R/G and B/Y) and achromatic mechanisms. Chromatic threshold increases were on average twice the increase observed in the achromatic mechanism for foveal and parafoveal measurements. The rate of increase, as a function of age, in chromatic thresholds (along R/G and B/Y mechanisms) showed an accelerated fashion from the 5th-6th decade onwards. Meanwhile the achromatic thresholds increased at a slower, linear rate throughout life. In spite of the initial, more rapid increase along the B/Y colour opponent system (particularly for foveal thresholds), there were no significant differences between the rate of ageing for R/G and B/Y mechanisms. The largest age-related loss of chromatic sensitivity occurs in the lower hemifield for the B/Y mechanism. In conclusion, both the glaucomatous damage and the ageing process lead to reduction in both R/G and B/Y chromatic sensitivity. The relative B/Y versus R/G chromatic loss in POAG depends on the severity of glaucomatous damage. The first signs of chromatic discrimination loss in the patients at risk of suffering POAG appear in the paracentral locations (7 deg) and are characterised by a non-selective loss of chromatic sensitivity and an increased inter- and within- subject variability. The relative age-related loss of R/G and B/Y sensitivity is mostly non- selective and independent of stimulus location.

The aim of this thesis is to disentangle the effects of trade liberalisation during the mid1980s from the trade liberalisation involved in the North American Free Trade Agreement (NAFTA) on exports, imports and the balance of payments in Mexico, at the aggregate and disaggregated level. The main empirical results suggest that the trade reforms during the mid-1980s had a significant impact on trade, exports and imports; however, the effects of NAFTA are negligible. In spite of the fast rate of manufacturing exports, the most dynamic sector, imports have increased even faster. Therefore, trade liberalisation has worsened the trade balance. In addition to this, the evidence presented in this thesis shows that more liberalised trade has not contributed to an improved economic performance in Mexico, as promised a decade ago, before NAFTA came into effect, by the leaders of Canada, Mexico and the US. However, NAFTA has locked-in Mexico's trade and foreign investment policy, easing the access of multinational firms to the country but with minimum forward and backward linkages to the domestic economy. It is corroborated that Mexico's economic performance is constrained by the external sector and trade liberalisation has contributed to reinforcing the dependence of domestic industry on imports.