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Stasis, Fragmentation, and Change: An Empirical Analysis of Police Reform in Jamaica (2000 - 2021)
No full textThe murder of an African American man, George Floyd, by a white police officer on May 25, 2020, in Minnesota, United States of America, ignited a wave of social movements and public outcry against police brutality globally. This increased focus on police violence and its connection to intersecting social hierarchies contributed to the resurgence of debates about this issue’s pervasiveness elsewhere, notably middle-income developing countries (MICs) in Latin America and the Caribbean (LAC) – contexts with some of the highest levels of homicides globally. Yet historically, efforts to reform police institutions and their practices have been disappointing despite significant financial investments. To remedy gaps in reform thinking and implementation, scholars have proposed various factors that they consider critical missing links, including research on implemented reform efforts may have underestimated or overlooked reform gains and the conditions that facilitated more promising outcomes. In response to these arguments, and with an optimism that sustainable institutional change is possible, this thesis uses Jamaica as a case study of police reform in a specific MIC in LAC. Using a broadened institutionalist theoretical lens and grounded in comparative case study methods, it focuses on the Jamaica Constabulary Force’s (JCF) reform outcomes, particularly about the use of force and factors influencing change in these outcomes.
The thesis is structured across four different but related articles. Specifically, articles one to three home in on the use of force and explore changes in the JCF at different levels of analysis: regional (Americas), national, and divisional. Article four complements the first three in its focus on change, but it adds depth by homing in on the conditions influencing change in the JCF. Combined, they offer a cohesive analysis of the JCF’s use of force and the conditions contributing to police reform. The collection of articles in this thesis makes several original contributions to the literature and discourse on security sector reform, particularly regarding policing and police reform in Jamaica and comparable contexts. Specifically, it makes a methodological argument for how police reform should be studied, theorises how change can be more consistently categorised, localises police reform at both the national and divisional/community levels, and re-emphasises the reform-crime interconnections
Résister à la violence des gangs : acteurs, mémoire et identité dans un quartier de Port-au-Prince
No full textCette thèse porte sur les actions menées à Canapé-Vert, un quartier situé à l’est de la ville de Port-au-Prince (Haïti), contre la violence des gangs. Elle adopte la sociologie culturelle des actions collectives, dans laquelle le culturel, les émotions et l’action symbolique occupent une place centrale. Elle part d’une conception impure de l’action dans laquelle sa frontière avec la violence est parfois poreuse. À partir d’une approche méthodologique combinant observations et entretiens semi-dirigés, cette étude révèle que l’action menée contre la violence des gangs dans le quartier s’inscrit dans la mémoire de bwakale. Ces actions transforment l’espace physique et social du quartier pour produire une identité de résistance. Cette identité façonne à son tour la mobilité des habitants du quartier dans la ville de Port-au-Prince. Néanmoins, cette identité de résistance ne parvient pas à s’inscrire dans l’espace public en raison de la peur. Les acteurs craignaient de devenir la cible des bandits et également d'être poursuivis en justice. En ce sens, les expériences vécues par les habitants du quartier, qu'elles soient souffrantes ou résistantes, ne sont publiquement témoignées
Access to Safe, Sustainable, & Healthy Housing in Cambridge Bay, Nunavut: An Institutional Ethnography
No full textThis institutional ethnography examines access to justice issues with respect to the housing crisis in Cambridge Bay, Nunavut, through interviews with 19 community members and 13 service providers, as well as a review of relevant texts including laws and policies. This project provides an original contribution to the field of research in two ways. First, it does so in what was studied, in addressing research needs that has been identified as a priority by Inuit, government, and other actors. Secondly, the project provides an original contribution in how it was studied, in proposing to use institutional ethnography, informed by Inuit Qaujimajatuqangit guidance on research practices, to understand access to justice in Nunavut. The research reveals how the ruling relations perpetuate the ongoing impacts of colonialism with respect to people's housing experiences across the housing continuum. This suggests that a broad, holistic understanding of access to justice is required in Nunavut. The research also challenges the suitability of a western, capitalist, individualist private market-based model of a housing continuum that has been transplanted from southern Canadian jurisdictions, which are grappling with their own housing crises themselves. Instead, it is time to envision a housing model that suits the unique needs of Nunavut and supports goals of Inuit self-determination. --
Cette ethnographie institutionnelle examine les questions d'accès à la justice en ce qui concerne la crise du logement à Cambridge Bay, au Nunavut, au moyen d'entretiens avec 19 membres de la collectivité et 13 fournisseurs de services, ainsi que d'un examen des textes pertinents, y compris les lois et les politiques. Ce projet apporte une contribution originale au domaine de la recherche de deux manières. Premièrement, il le fait au niveau du sujet étudié, en répondant aux besoins de recherche identifiés comme prioritaires par les Inuits, le gouvernement et d'autres parties prenantes. Deuxièmement, le projet apporte une contribution originale dans la manière dont le sujet a été étudié, en proposant d'utiliser l'ethnographie institutionnelle, éclairée par les conseils de l'Inuit Qaujimajatuqangit sur les pratiques de recherche, pour comprendre l'accès à la justice au Nunavut. La recherche révèle comment les relations de pouvoir perpétuent les répercussions actuelles du colonialisme en ce qui concerne les expériences de logement des personnes dans l'ensemble du continuum du logement. Cela suggère qu'il faut envisager une compréhension large et holistique de l'accès à la justice au Nunavut. La recherche remet également en question la pertinence d'un modèle occidental, capitaliste, individualiste et basé sur le marché privé d'un continuum de logement qui a été transplanté des provinces du sud du Canada, qui sont elles-mêmes aux prises avec leurs propres crises du logement. Il est temps d'envisager un modèle de logement qui réponde aux besoins uniques du Nunavut et soutienne les objectifs d'autodétermination des Inuits
Developing New Cardioprotective Strategies for Prevention of Chemotherapy-induced Cardiotoxicity
No full textCardiovascular diseases stand as the leading cause of morbidity and mortality worldwide. Heart failure (HF) is the end stage of numerous cardiovascular diseases including coronary artery disease and hypertension. The quest for effective treatment is an ongoing endeavor. While current drugs used in clinical settings serve to slow down the disease progression, they fall short of offering a definitive cure. The limited proliferative capacity of cardiomyocytes post-maturity, coupled with scar formation in response to stress or injury, poses a significant challenge in finding a definitive treatment. This thesis aims to investigate the potential of a newly identified nucleoside analogue, LCB-2122, as a cardioprotective agent in different HF and cardiomyocyte stress models. In vivo and in vitro cell and molecular techniques were employed for this. First, we show that LCB-2122 enhances cardiac functions in acute and chronic mouse models of HF. In doxorubicin (Dox) treated mice and transgenic mice overexpressing the angiotensin II type 1 receptor (AT1R), treatment with LCB-2122 reduced the expression of cardiac stress markers and enhanced ejection fraction (%EF). We further investigated the mechanism of cardioprotection of LCB-2122. In AT1R transgenic mice treated with LCB-2122, transmission electron microscopy shows improved structural organization of myofibrils and mitochondrial ultrastructure. In neonatal rat cardiomyocytes, treatment with LCB-2122 decreases Dox-induced elevation in reactive oxygen species and maintains metabolite homeostasis. Furthermore, co-treatment with Dox and LCB-2122 preserves mitochondrial respiration and function. The mechanism of cardioprotection of LCB-2122 is linked to an indirect activation of the AMP-activated protein kinase (AMPK) pathway and its downstream targets. Lastly, the study of structure-function relationship using LCB-2122 derivatives ruled out that LCB-2122 is a prodrug and identified the essential functional groups of this molecule to help enhance its pharmacological properties. Together, this study introduces nucleoside analogues as new therapeutic strategies for the treatment of acute and chronic HF. LCB-2122 effect on mitochondrial health and survival pathways highlights its potential as a promising candidate for further investigation in HF therapy
Essays on Empirical Corporate Finance
No full textIn this dissertation, I investigate important questions in the realm of empirical corporate finance. The research topics include with-in firm pay inequality and dividend policy (first chapter), the determinants and predictive power of SPAC shares redemption (second chapter), and the firm-level political risk and stock repurchases (third chapter). The first and third chapters are co-authored with Dr. Ali Akyol, and the second chapter is single authored.
The first chapter examines CEO behavior in response to within-firm pay inequality. Using CEO-median employee pay ratio data mandated by the SEC, the study reveals that following the release of pay ratio disclosures, CEOs with higher pay ratios tend to issue higher dividend payments as a strategy to mitigate adverse reactions from the investors and market than those with lower pay ratios. The positive correlation between CEO pay ratio and dividend payouts is consistently observed on both yearly and quarterly basis. The relationship between CEO pay ratio and dividend payouts remains robust when taking into account various firm characteristics and external shocks such as the COVID-19 pandemic and overall market condition. Furthermore, we employ instrumental variable regression analysis, subsample analysis, alternative measures analysis, and omitted variables analysis to validate the findings. On the other hand, the results indicate that CEO pay ratio does not significantly impact stock repurchases, as the decision of stock repurchases is sensitive to exogenous shocks, and stock repurchases lead to potential shareholder base loss.
In the second chapter, I address potential factors affecting investors' share redemption decisions in Special Purpose Acquisition Companies (SPACs). I show that investors demand information on SPACs from different sources, and several relevant factors are identified from the SPAC side, the target company side, and the merger deal and financial market side. I also find that the SPAC share redemption rate shows predictive power for post-merger operational performance. Furthermore, the redemption rate significantly predicts the post-merger stock performance for original SPAC shareholders but not for the new shareholders who purchase stock shares in the newly merged firm after the merger.
In the third chapter, we use a novel measure of firm-level political risk developed by Hassan, Hollander, Van Lent, and Tahoun (2019) to explain stock repurchase activities in publicly listed U.S. firms. With our monthly open-market repurchase data, we find a positive and significant effect of firm-level political risk on open-market repurchases. The positive association also exists in the subcategories of political risk related to economics, environment, institutions, security, tax, and technology. We find that firms' ROA volatility and growth potential act as intermediary effects on the relationship between political risk and repurchases. Further, we conduct robustness checks including omitted variables, instrumental variable analysis, subsample tests, and propensity score matching. The results of robustness checks support our main hypothesis and are consistent with our primary findings
Bifacial Photovoltaic Performance and Optimization in Mid-to-High Latitudes
No full textAs early as the 1980s, photovoltaic (PV) modules have been deployed in high latitude regions to power buildings and equipment. However, it is only in recent years that significant PV deployments have begun to occur in these regions thanks to the continued drop in PV module costs. Historically, PV technologies have been deployed in low-to-mid latitude locations where solar resource is high and the economics of PV were more suitable. In these regions snowfall is rare or non-existent. This thesis supports efforts to bridge the knowledge gap between PV systems designed, operated, characterized, and modelled in low-to-mid latitudes and PV systems in high latitude, northern locations. Bifacial PV technologies are, in particular, explored due to their added benefits in regions with regular snowfall and cloud cover. The research presented in this thesis spans from the cell-level to the system-level and includes both experimental and modelling work.
One of the main challenges for PV systems in high latitudes is predicting their performance under high latitude operating conditions. This is particularly challenging for bifacial PV technologies where the added complexity of rear-side light is heavily influenced by the surrounding environment and illumination conditions. In this thesis, emerging high efficiency and high bifaciality silicon heterojunction solar cells are simulated and measured under high latitude operating conditions. A methodology for testing bifacial devices indoors that incorporates the effects of additional illumination from rear-side ground cover is developed.
Several bifacial PV system-level models are discussed and explored in this thesis for simulating mid-and-high latitude PV systems, including emerging vertical PV designs. Vertical PV systems have been deployed in recent years in smaller-scale sites (<1 MW) due to their suitability in high latitudes and in agri-photovoltaic applications. The effects of varied row spacing and module tilt are explored as a function of latitude, and empirical equations are developed for calculating system row spacing given deployment latitude and configuration (fixed-tilt, tracked, or vertical systems). The sensitivity of bifacial PV energy yield models to input albedo is explored via the calculation of spectral albedo mismatch as a function of latitude for 10 different ground cover scenarios, demonstrating a tendency towards increased modelling uncertainty in high latitudes.
This thesis also presents the highest latitude location model validation effort to-date at 65°N and validates five PV models for emerging vertical bifacial PV systems. Vertical PV systems are found to have higher modelling uncertainty than equator-facing fixed-tilt systems, however hourly and seasonal trends are generally well predicted by the models. Finally, the degradation of PV systems in cold, snowy climates is reviewed and new analysis is presented for four PV systems >60°N. PV systems deployed in cold climates tend to degrade slower than warmer climates, which is an indication that PV systems in high latitudes may out-live their lower-latitude counterparts.
Overall, the six papers presented in this thesis support continued development of mid-to-high latitude PV and demonstrate that PV technologies can be used to provide reliable, seasonal electricity. PV systems must be designed with high latitude environmental conditions in mind, higher tolerances to uncertainty, and to meet northern energy priorities
Strategies and resources used by public health units to encourage COVID-19 vaccination among priority groups: a behavioural science-informed review of three urban centres in Canada
No full textAbstract Background Ensuring widespread COVID-19 vaccine uptake is a public health priority in Canada and globally, particularly within communities that exhibit lower uptake rates and are at a higher risk of infection. Public health units (PHUs) have leveraged many resources to promote the uptake of recommended COVID-19 vaccine doses. Understanding barriers and facilitators to vaccine uptake, and which strategies/resources have been used to address them to date, may help identify areas where further support could be provided. We sought to identify the strategies/resources used by PHUs to promote the uptake of the first and third doses of the COVID-19 vaccine among priority groups in their jurisdictions. We examined the alignment of these existing strategies/resources with behavioral science principles, to inform potential complementary strategies/resources. Methods We reviewed the online and in-person strategies/resources used by three PHUs in Ontario, Canada to promote COVID-19 vaccine uptake among priority groups (Black and Eastern European populations, and/or neighbourhoods with low vaccine uptake or socioeconomic status). Strategies/resources were identified from PHU websites, social media, and PHU liaison. We used the Behaviour Change Techniques (BCT) Taxonomy – which describes 93 different ways of supporting behaviour change – to categorise the types of strategies/resources used, and the Theoretical Domains Framework – which synthesises 14 factors that can be barriers or facilitators to decisions and actions – to categorise the barriers and facilitators addressed by strategies/resources. Results PHUs operationalised 21 out of 93 BCTs, ranging from 15 to 20 BCTs per PHU. The most frequently operationalised BCTs were found in strategies/resources that provided information about COVID-19 infection and vaccines, increased access to COVID-19 vaccination, and integrated social supports such as community ambassadors and engagement sessions with healthcare professionals. Identified BCTs aligned most frequently with addressing barriers and facilitators related to Knowledge, Environmental context and resources, and Beliefs about consequences domains. Conclusion PHUs have used several BCTs to address different barriers and facilitators to COVID-19 vaccine uptake for priority groups. Opportunities should be pursued to broaden the scope of BCTs used (e.g., operationalizing the pros and cons BCT) and barriers/facilitators addressed in strategies/resources for ongoing and future COVID-19 vaccine uptake efforts among general and prioritised populations
Defence and Military Reform in Ukraine 2014-2022
No full textDespite having inherited a massive military at independence in 1991, the Ukrainian military response to Russian aggression in 2014 was characterized by defeat. Yet, eight years later in 2022 the Ukrainian military’s response to a large-scale Russian invasion was dramatically improved. This thesis examines how this surprising improvement occurred, given that similar reform efforts between 1991-2014 had failed. The analysis focuses on three key interrelated elements of military professionalism, namely external legitimacy, combat capability and internal legitimacy. The focus on military professionalism places the military at the centre of analysis, while simultaneously permitting visibility of other central actors in the reform story – the Ukrainian government, Ukrainian society, and external actors. Drawing on the concept of path-dependency and previous literature on military reform in Ukraine, the thesis explores how Soviet legacies ‘locked in’ forms of behaviour and structures, thus preventing significant reform in the period from independence in 1991 to the outbreak of the Donbas war in 2014. The thesis argues that a ‘critical juncture’ opened with the Maidan Revolution in late 2013 prompting events of early 2014: the fall of Yanukovych regime, annexation of Crimea by the Russian Federation and outbreak of the Donbas war. The thesis argues that the critical juncture provided the conditions of possibility for reform activities for the Ukrainian Armed Forces (UAF) and that genuine improvement in the three areas of military professionalism occurred as a result, evident in post-2022 battlefield success. Overall, this thesis shows that deeply sedimented military practices resulting from path dependency can be broken by critical junctures, but that this requires a political will that is aligned with the military itself and supported by domestic society and the international community. The analysis relies on data from documents, interviews, and secondary sources. Op Unifier, the Canadian military assistance mission was a primary source of data using perspectives of the CAF personnel implementing the security assistance and contributes to understanding of military reform processes from the bottom-up
Hypoxia Increases Cytosolic Ca2+ in Goldfish Horizontal Cells Exposed to Glutamate
No full textCentral neurons of the common goldfish (Carassius auratus) are exceptional in their capacity to survive Ca2+-induced excitotoxicity and cell death during hypoxia. Horizontal cells (HCs) are inhibitory interneurons of the retina that are tonically depolarized by the neurotransmitter, glutamate, yet preserve intracellular Ca2+ homeostasis. In HCs isolated from goldfish, and in the absence of glutamatergic input, intracellular Ca2+ concentration ([Ca2+]i) is protected from prolonged exposure to hypoxia by mitochondrial ATP-dependent K+ (mKATP) channel activity. In the present study, we investigated the effects of hypoxia upon [Ca2+]i in isolated HCs during tonic activation by glutamate to better predict the effects of hypoxia in the active retina. Dynamic changes in [Ca2+]i were measured using the ratiometric Ca2+ indicator, Fura-2. Application of 100 µM glutamate during hypoxia (PO2 = 25 mmHg) produced a greater rise in [Ca2+]i compared to the same glutamate stimulus during normoxia. The hypoxia-dependent increase in [Ca2+]i was abolished by application of 5-hydroxydecanoic acid, which renders mKATP channels inactive. Extracellular Ca2+ did not contribute to the elevated [Ca2+]i observed during hypoxia, as the effect persisted in Ca2+-free solution and during application of verapamil, an L-type Ca2+ channel blocker. By contrast, inhibition of the mitochondrial Ca2+ uniporter or ryanodine receptors (with ruthenium red or ryanodine, respectively) abolished the hypoxia-dependent rise in [Ca2+]i. This study reports a paradoxical mKATP-dependent rise in [Ca2+]i during hypoxia in HCs activated by glutamate, and suggests roles for the mitochondria and intracellular Ca2+ stores in regulating this mechanism.
Les neurones centraux du poisson rouge commun (Carassius auratus) sont exceptionnels dans leur capacité à survivre à l'excitotoxicité induite par le Ca2+ et à la mort cellulaire pendant l'hypoxie. Les cellules horizontales (CH) sont des interneurones inhibiteurs de la rétine qui sont à la fois dépolarisées de manière tonique par le neurotransmetteur, le glutamate, tout en préservant l'homéostasie intracellulaire du Ca2+. Dans les CH isolées du poisson rouge, et en l'absence d'entrée glutamatergique, la concentration intracellulaire en Ca2+ ([Ca2+]i) est protégée d'une exposition prolongée à l'hypoxie grâce à l'activité des canaux K+ mitochondriaux dépendant de l’ATP (mKATP). Dans cette étude, nous avons étudié les effets de l'hypoxie sur [Ca2+]i dans des CH isolées pendant l'activation tonique par le glutamate afin de mieux prédire les effets de l'hypoxie dans la rétine active. Des changements dynamiques dans [Ca2+]i ont été mesurés à l'aide de l'indicateur de Ca2+ par rapport, Fura-2. L'application de 100 µM de glutamate pendant l'hypoxie (PO2 = 25 mmHg) a produit une augmentation plus importante de [Ca2+]i par rapport au même stimulus de glutamate pendant la normoxie. L'augmentation de [Ca2+]i dépendante de l'hypoxie a été abolie par l'application d'acide 5-hydroxydécanoïque, qui rend les canaux mKATP inactifs. Le Ca2+ extracellulaire n'a pas contribué à l'élévation de [Ca2+]i observée pendant l'hypoxie, car l'effet a persisté dans une solution sans Ca2+ et pendant l'application de vérapamil, un bloqueur des canaux Ca2+ de « L-type ». En revanche, l'inhibition du transporteur uniporteur de Ca2+ mitochondrial ou des récepteurs à la ryanodine (avec du rouge de ruthénium ou de la ryanodine, respectivement) a aboli l'augmentation de [Ca2+]i dépendante de l'hypoxie. Cette étude rapporte une augmentation paradoxale de [Ca2+]i dépendante des mKATP pendant l'hypoxie dans des CH activées par le glutamate, et suggère des rôles pour les mitochondries et les réserves intracellulaires de Ca2+ dans la régulation de ce mécanisme
TriLLIEM: Triad Log-Linear Modelling of Imprinting, Environmental Interactions, and Maternal Effects
No full textThe case-parents design, where an affected child and their parents are genotyped, allows for estimation of disease risk due to either the child's or mother's genes through log-linear modelling. It is robust to the confounding effects of population subdivision, but cannot account for non-exchangeability of parental genotypes. Factors such as gene-environment interactions and imprinting, where risk depends on which parent contributed a genetic factor, can also be estimated. Existing analytical software are either deprecated (LEM) or have limited modelling capabilities (Haplin, EMIM). We introduce our R package, TriLLIEM, which implements the log-linear approach to address these limitations. The software includes options for gene-environment interactions, imprinting by environment interactions, and non-exchangeable parental genotypes if parents of controls are also available. We use these features in a simulation study to assess the accuracy of TriLLIEM and to show how population stratification confounds the model for gene-environment interactions when control-triads are included