VictorJuiz/thesis huggingface dataset:
Functional Nanomaterials for Gas-phase Heterogeneous Photocatalysis: Toward Efficient Solar Fuel Production
Keywords: Artificial photosynthesis
Carbon dioxide
Indium oxide
Metal oxides
Nanoparticles
Solar fuels

Harnessing abundant solar energy to facilitate the capture and conversion of greenhouse gas CO2 into carbon-based fuels and chemical feedstocks represents a significant scientific challenge with implications for both climate change and sustainable energy production. Herein, we have demonstrated that highly defected indium oxide, In2O3-x(OH)y, nanoparticles can function as effective gas-phase photocatalysts for CO2 reduction to CO via the reverse water gas shift (RWGS) reaction. Significantly we have found that the presence of both oxygen vacancies and surface hydroxide groups are necessary to facilitate the reaction. Using transient absorption spectroscopy we demonstrated that these defects play a significant role in the excited state charge relaxation pathways, with higher defect concentrations resulting in longer excited state lifetimes, which is attributed to electron and hole trapping in oxygen vacancies and surface hydroxide groups, respectively. This supports the proposed surface Frustrated Lewis Pair (FLP) reaction mechanism, in which a surface active site composed of a Lewis acidic, coordinatively unsaturated indium atom, created by the presence of an oxygen vacancy, adjacent to a Lewis basic hydroxide, assists the adsorption and heterolytic dissociation of H2, which then enables the adsorption and reaction of CO2 to form CO and H2O. Preliminary results indicate that photogenerated electron and hole localization in these defects enhances their Lewis acidity and basicity, lowering the activation energy for the RWGS reaction under illumination. Finally, we demonstrated that by evenly dispersing In2O3-x(OH)y nanoparticles on vertically aligned silicon nanowires (SiNW), we can increase reaction rates by improving reflective losses and facilitating light trapping in the region of the solar spectrum where In2O3-x(OH)y absorbs. Further, by using the photothermal properties of the SiNWs, the light energy not absorbed by In2O3-x(OH)y can be converted into localized heat energy, removing the need for external heating and improving the overall energy efficiency of the process.
A Simple Animal Model for Characterizing Gene Reglatory Control of an Immune Response
Keywords: comparative immunity
gut immunity
IL-17
innate immunity
sea urchin

A robust but tightly regulated system of innate gut immunity is required for maintaining gut homeostasis. Given the complex nature of the mammalian gut, a simple yet phylogenetically relevant model is useful to decipher the underlying molecular controls that sustain this balance. Here I use the purple sea urchin larva as a morphologically simple model for these studies. I approach this problem with three interrelated strategies: (1) Characterization of larval immunocytes based on morphology, cell behaviour and gene expression, (2) analysis of gene activity in a model of gut-associated immune response to bacteria and (3) regulatory analysis of selected response genes. I characterize five larval cell types that are active in gut immunity and develop a gut associated infection model using the bacterium Vibrio diazotrophicus. RNA-seq analysis of this model is used to identify immune genes that are differentially expressed over the course of infection. Member of the sea urchin IL-17 multigene family are identified as immune response genes. One subfamily, SpIL-17-I, is expressed early upon exposure to V. diazotrophicus in the mid- and hindgut and is then attenuated. BAC-based GFP transgenes and smaller reporter constructs recapitulate endogenous SpIL-17-I expression. Regulatory regions are defined upstream and downstream of the IL-17 coding sequence. Deletions of critical elements results in a decrease or absence of IL-17 expression but never ectopic expression or expression in the absence of immune stimulus. Downstream function of IL-17 was investigated by perturbing its receptors using Morpholino antisense oligonucleotides. In addition to physiological changes in the larva, expression of several immune effector genes are downregulated in IL-17R perturbed embryos. Collectively this work suggests that a core network of regulatory circuitry is shared with the vertebrates in the gut associated immune response even in this simple larval form. This can then form the basis for more elaborate network analysis of gut immunity in future studies using this model.
The Social and Cultural Worlds of Elite Valencian Youth, 1300-1500
Keywords: adolescence
chivalry
femininity
masculinity
Valencia
youth

This study examines the socio-cultural position of adolescents and youths – those between the approximate ages of fifteen and twenty-five years old – within aristocratic and patrician society in late medieval Valencia. It investigates how young people were defined and described by adult society, as well as how young people understood their own relationship with sources of adult authority – sometimes acquiescing to it and sometimes actively resisting it – and concludes that, far from being an insignificant or abbreviated period of transition from childhood to adulthood, adolescence was a vital and protracted period of preparation that was believed to require special vigilance and attention from adult society to ensure that adolescents and young adults became “successful” members of society. The study begins, in Part I, by investigating how adolescence was understood and defined by the Valencian legal code, the Furs, which collectively codified adolescence as a period of “quasi-adulthood.” Then, the second part examines how adolescence and youth were constructed in works of prescriptive literature composed by ecclesiastical and secular authors in late-medieval Valencia, with particular attention given to the writings of the Franciscan writer Francesc Eiximenis, as well as Ramon Llull’s Llibre de l’orde de cavalleria, and Joanot Martorell’s chivalric epic, Tirant lo Blanc. These sources highlight the importance of paternal or adult supervision of a child’s education, while also giving insight into societal constructions of aristocratic masculinity and femininity, aristocratic honor, masculine aggression, and socially acceptable forms of sexual expression between young men and women. Finally, Part III of this study explores how the values expounded by the sources used in Parts I and II were expressed by young people within society. Using legal records (court cases and judicial records) and documentary materials, this section analyzes how young members of aristocratic households, particularly squires and the younger members of aristocratic families, were socialized into the culture of violence, honor, and “proper” sexual comportment by adult society and, consequently, reproduced these values in their own lives.
Constructing In/Security in the Arctic: Polar Politics, Indigenous Peoples, and Environmental Change in Canada and Norway
Keywords: Arctic Security
Canada
Environmental Change
Indigenous Peoples
Norway
Securitization

As climate change transforms the circumpolar Arctic, ‘Arctic security’ has increasingly been used as a concept to address the most urgent related policy questions. But security is a contested concept, and there is contradiction among the various understandings of what it actually entails in the Arctic region. This dissertation investigates competing conceptions of security and environmental change by state and non-state actors in the Arctic regions of Canada and Norway. It asks why, despite being understood as a threat to national and global security by other states and in other regional contexts, has climate change not been constituted as a security threat by Arctic states? I examine this question through a comparative analysis of Canada and Norway’s foreign and security policies, how they construct the significance of climate change, and those policies’ correspondence with local Indigenous conceptions of Arctic security. The findings suggest that the conception of security held by Arctic Indigenous peoples have been structurally excluded from official Arctic security discourse. The dissertation makes three central contributions: it offers a comparative analysis of circumpolar states’ understandings of Arctic security; it undertakes the first comparative analysis of Indigenous understandings of Arctic security; and it proposes a revised theory of how certain identities condition the process through which in/security is socially constructed.
The Impact of Internationalization on the Regionalization of Higher Education in the English-speaking Caribbean: A Case Study of the University of the West Indies
Keywords: Caribbean
Education
Internationalization
Regionalization
University of the West Indies
West Indies

The University of the West Indies (UWI) is one of two regional universities in the world. In the history of the 'West Indies,' successive European colonizers attempted to form a federation of the Windward and Leeward Islands. Both the colonial administration and the independence movements which created a rising elite in these former British colonies, had political and economic motivations for establishing a regional university, and advancing functional cooperation through an integration mechanism - the Caribbean Community (CARICOM). Following the 1958 to 1962 Federation experiment, the UWI became enshrined as a symbol of Caribbean integration. But the challenges of surviving and competing in the global economy have persisted. In their post independence struggles for economic survival, the Anglophone Caribbean seems to have substituted political for economic dependence, with continued reliance on extra-regional funding authorities. As such, in the new neoliberal reality, the UWI must produce human capital - knowledge workers - to fulfill labour market needs; develop commercial research, and support continued regional economic development, with reduced government funding, under increasing levels of accountability. With globalization and internationalization, the UWI is in the process of broadening its mandate, to include the other linguistic and ethnocultural groups, constituting the larger Caribbean area, including Central and Latin America. As part of its internationalization strategy, it has increased inter-institutional partnerships and other collaborative practices, within the region and extra-regionally. Globalization, neoliberalism, regionalization and internationalization have also given rise to many challenges. They have facilitated intercultural experiences, academic mobility and non-traditional delivery mechanisms in higher education. However, the struggles to finance national economies and higher education, have led to tensions in national sovereignty and regional aspirations within CARICOM. The central question for this research was whether internationalization is advancing or hindering regionalization mandate of the University of the West Indies in the Anglophone Caribbean.
Lambek Categorial Grammars for Practical Parsing
Keywords: Categorial Grammar
CCG
Generative Capacity
Parsing
Semantics
Syntax

This dissertation investigates which grammar formalism to use for representing the structure of natural language in a practical parser, and advocates the use of Lambek Categorial Grammar (LCG) over similar formalisms such as Combinatory Categorial Grammar (CCG). Before we argue for the advantages of LCG, we first overcome two obstacles to its use in practical parsers: its NP-Complete parsing problem, and its weak equivalence to Context-Free Grammars (CFGs). We develop a parsing algorithm for LCG that is polynomial when the order of categories in the grammar is bounded by a constant. Furthermore, we show that in CCGbank, the only existing categorial grammar corpus, the order of categories is very low. Next, we analyze the Clark and Curran parser, the state of the art in categorial grammar parsing, and establish that the CCG that it uses is also weakly equivalent to CFGs. Then, we train the Petrov parser, a probabilistic CFG parser, on CCGbank and obtain the best results to date on the test set. This establishes that LCG's weak equivalence to CFGs is not a hindrance to its use in a practical parser. Having established the viability of using LCG in a parser, we then argue for its superiority over CCG as a representation for the structure of natural language sentences. We show that LCG offers a greater transparency between its syntactic structure and the categorial semantics that can be built from a parse of a categorial grammar. As part of this argument, we show that representing LCG derivations as proof nets allows for a more cohesive representation of categorial syntax, dependency structures and categorial semantics than CCG. To demonstrate this, we develop a corpus of LCG derivations by semi-automatically translating the CCG derivations of CCGbank into LCG proof nets.
A Task Analysis of how Clients Formulate Reappraisals in Cognitive Behaviour Therapy for Depression
Keywords: CBT
change process
cognitive therapy
depression
dysfunctional appraisal
task analysis

The generation of adaptive appraisals of self are theorized to play a key role in the effective treatment of depression in cognitive-behavior therapy (CBT), yet there are few descriptive analyses of clients' in-session behavior during dysfunctional appraisal tasks. The primary objectives of this investigation were to develop a model to describe how clients resolve a dysfunctional appraisal task in CBT for depression (Rice Greenberg, 1984), and to examine the relationship between higher degrees of resolution of a dysfunctional appraisal, and good outcomes in psychotherapy. A task analysis was used to develop and test a model of resolution of dysfunctional appraisals. In the first phase, a rational model of the expected sequence of client processes was developed from a review of relevant literature. An empirical model was then derived by comparing resolved and non-resolved events within 13 transcripts from archival data of a CBT for clinical depression treatment (Goodridge Hardy, 2009). The rational and empirical models were synthesized. The sequence of components described by this model are: the Dysfunctional Appraisal task marker, Elaboration, Accessing Vulnerability, Shift: Softening and/or Shifting Perspective, Evaluating New Perspective, and Reappraising (task resolution). In the second phase, the validity of the model was examined. A measurement tool, the Degrees of Resolution Scale of a Dysfunctional Appraisal task (DRS-DA), was created. The DRS-DA is an observer-rated 7-point measure representing the presence of the components of the derived model. Higher ratings on the DRS-DA indicate higher degrees of resolution of the dysfunctional appraisal task. To investigate the relationship between the model and outcome, 22 transcripts were used from archival data of a CBT for clinical depression treatment (Watson et al., 2003). Results demonstrated that there was a relationship between DRS-DA score and post-session change. Moreover, DRS-DA scores differentiated between good and poor outcome clients, and good outcome clients were more likely to demonstrate Evaluating New Perspective in their highest reported change sessions than poor outcome clients. This study provides preliminary support for the model.
Diaphragm Activity and Function During Mechanical Ventilation
Keywords: Diaphragm
Mechanical ventilation
Muscle function
Ultrasound
Weaning

Previous studies suggest that mechanical ventilation (MV) can injure the diaphragm, potentially prolonging ventilator dependence. However, there are many potential insults to diaphragm function during critical illness and the extent to which diaphragm dysfunction is attributable to ventilation remains undefined in the clinical setting. We hypothesized that diaphragm inactivity and/or injurious diaphragm loading during MV mediate diaphragm injury in the clinical setting. To test this hypothesis, we first evaluated the feasibility, validity and reproducibility of novel methods for monitoring the diaphragm in the clinical setting. We found that neuromuscular coupling (NMC), a measure of diaphragm function, is influenced by inspiratory effort, airway flow and diaphragm motion during inspiration and that NMC varies considerably over time in healthy volunteers. We also found that right hemidiaphragm thickness can be measured reproducibly by ultrasound and that increasing diaphragm thickness during inspiration reflects active contractile activity rather than passive chest wall expansion. Subsequently, in a large prospective cohort study (n=107) we demonstrated that diaphragm thickness varies considerably over time in relation to the level of inspiratory effort. Changes in muscle thickness were associated with impaired muscle function. Finally, in a preliminary clinical study (n=10) we confirmed the feasibility of selectively enrolling patients at high risk of prolonged MV and of measuring diaphragm activity and patient-ventilator dyssynchrony on an hourly basis commencing shortly after intubation. We conclude that ultrasound is a useful clinical tool to monitor the diaphragm during MV; NMC measurement requires further standardization and validation. MV likely causes significant diaphragm injury in patients and titrating ventilatory support to maintain normal levels of inspiratory effort may protect the diaphragm from injury during MV. A detailed description of patient exposure to diaphragm inactivity and injurious loading during MV is feasible; such observations could inform the design of muscle-protective ventilation strategies.
Access to Healthcare by Pregnant and Lactating Women Living with HIV and AIDS in Kenya
Keywords: Access to healthcare
HIV/AIDS
Maternal health
Postcolonial feminism
Qualitative methods
Sub-Saharan Africa

Maternal deaths are the second biggest killer of women of reproductive age. High maternal deaths in sub-Saharan Africa reflect inequities in health services. This study explored how intersecting factors such as gender, class, and other social relations shape access to healthcare among a selected group of HIV-positive Kenyan. Guided by a postcolonial feminist perspective, the study employed semi-structured interviews to elicit the perspectives of key institutional actors on the challenges and constraints of the health services landscape and in-depth interviews to gain insight into the lived experiences of individual women’s access to healthcare within the healthcare and social context of a purposively selected large Kenyan town. Key institutional actors’ perspective indicated that the healthcare system is complex, in flux, and homogenized women. They acknowledged that a lack of adequate healthcare funding resulted in unmet needs for people living with HIV, gaps in training of health practitioners and shortage of medical equipment and supplies. Women’s narratives revealed the complexities of their lives. Women’s diversity and agency were reflected in their stories about how they accessed healthcare within this complex healthcare system and within the existing social constraints in this setting. Women engaged with patriarchy and employed various strategies to access healthcare and strive for positive living. Positive social interactions such as social support were instrumental in motivating women’s access to healthcare. Negative social interactions, such as stigma, blame and social obligations, worked to both hamper and motivate women to access healthcare. Women’s social class intersected with gender and these other social relations to determine their access to healthcare. A lack of consideration of women’s heterogeneity results in a failure to account for how structures of oppression and gendered inequities translate into diverse material risks for women and impact their ability to access healthcare. A postcolonial feminist perspective, that listened to silenced and homogenized voices, is an effective tool to unmask the circumstances and conditions that affected women’s access to healthcare. This study contributes to the research on maternal health in countries with high maternal mortality and provides the basis for planning and implementing equitable care at local and national levels.
The (un)Natural Baroque: Giambattista Marino and Monteverdi's Late Madrigals
Keywords: Claudio Monteverdi
Giambattista Marino
Italian poetry
Late Renaissance
Seicentismo
Seventeenth-century Italy

The early decades of the seventeenth century saw an important aesthetic shift in Italian secular music. The madrigals of Claudio Monteverdi (1567–1643) have often been seen to bridge the gap between the Renaissance and the Baroque since they introduced instrumental writing and operatic elements into a traditionally vocal genre. There is an unmistakable change in Monteverdi’s approach to madrigal composition at the beginning of his Venetian period (ca. 1613), and his revised approach to Italian poetry in his later books of madrigals produced some of the most opulent yet splendidly complex music. Although Monteverdi is best known for having broken the rules of sixteenth-century counterpoint in order to unify text and music—what he called the seconda pratica—poetry and music are often at odds in his late secular works. It is this discord between music and poetry that has resulted in the generally negative view of Monteverdi’s late madrigals. Gary Tomlinson has argued that the primary impetus for the change in Monteverdi’s musical approach to text and form arose from the deadening influence of “Marinism,” the poetic movement inspired by the sensual, baroque, and at times controversial poetry of Giambattista Marino (1569–1625). In challenging the view that Marino’s poetic style indicated artistic decline, I propose that Marinism inspired a new madrigalian aesthetic which reflected the particular artistic climate of the early Seicento. Monteverdi’s settings of Marino’s verses—found in his last three madrigal books (1614–38)—had artistic aims different from those of his earlier madrigals. Because Monteverdi revised his approach to madrigal composition at the time of his arrival in Venice, his secular works from this period require a different analytical approach, one developed for and tailored to the repertoire’s unique aesthetic. By examining the literary and societal atmosphere of the early seventeenth century, this dissertation seeks to explain the stylistic change in Monteverdi’s madrigals by showing that it reflects a similar shift in the literature of the early Seicento.