VictorJuiz/thesis huggingface dataset:
Investigating Drought Impacts on Plant Functional Traits Using Hyperspectral Remote Sensing

Grasslands are among the most endangered and least protected ecosystems on Earth due to the impacts of livestock grazing, agricultural land conversion, invasive species, extreme weather events, especially droughts. The characterization and assessment of native and invasive species distribution and functional traits in response to drought provide insights into plant biological and ecological processes and ecosystem functioning. Remote sensing has been used to map grassland species and assess functional traits at various spatial and temporal scales. Furthermore, it has been used to distinguish native and invasive species. However, the use of broadband multispectral or coarse spatial-resolution imagery in previous studies resulted in the over- or under-estimation of plant traits, especially in rugged terrain with small, highly mixed, and highly dynamic species. Airborne hyperspectral imagery, with high spatial resolution and hundreds of contiguous narrow bands, can be used to assess subtle changes in plant traits and species composition. The combination of hyperspectral imagery and topographic data provides insights into the effect of topographic variability on trait variation and trait responses of native and invasive species under drought stress. This study aims to investigate the integration of airborne hyperspectral imagery, field and laboratory measurements, topographic data, and machine learning to detect early drought impact and characterize the compositional and trait responses of native and invasive species. A series of experiments from greenhouse drought simulations to landscape-level natural drought experiments were conducted to understand how species respond to drought stress at different spatial and temporal scales. Results show that hyperspectral images, together with machine learning, outperform the traditional use of spectral indices and multispectral data in early drought detection and species classification. Plant functional trait analyses demonstrate that hyperspectral data can effectively estimate leaf and canopy functional traits and capture their responses to drought between native and invasive species in an area with small-scale topographic variability. This study sets a methodological basis for the advancements of remote assessment of trait response in native and invasive species under stress environments and provides essential information for invasion control and management to protect native ecosystems and wildlife habitats.

Keywords: Early Drought Detection
Grassland Drought
Hyperspectral Remote Sensing
Plant Functional Traits
Species Classification
Topography-Driven Trait Variation
Advisor: He, Yuhong
Political Economy of Road Building in Nepal: Limits of Social Transformative Change

This dissertation examines the relationship among road building, critical consciousness and social relations in Nepal, with a focus on rural roads as a key site of socio-political action. After the Maoist revolution (1996- 2006), roads have become a primary site, not only of investment in “post-conflict” state-building but also of people’s aspirations for self-governance. At the same time, road building provides opportunities for elites and foreign donors to consolidate power and dominance. Thus, I consider road building as an important but under-examined terrain of hegemonic practice, as well as a potential site for transformative social relations. The dissertation poses three questions: First, what governmental rationalities of road building have shaped planning processes, and what policies and programs have resulted? Second, how do road-building processes manifest prevailing social relations? Third, what critiques or alternative visions have been articulated and what are the limits and possibilities for transformative social change? It draws on three theoretical frameworks. Political economy prompts queries about histories of regional integration and contemporary territorializing regimes. Cultural politics facilitates consideration of how road building reproduces or challenges prevailing social relations, and what critiques or alternative visions have been articulated. Critical adult education emphasizes connecting analysis to praxis. These theoretical inquiries entail dialectically examining how social relations build roads and are in turn constituted through road-building processes. The research design is ethnographic—engaging both semi-structured interviews (with diverse actors involved in road building) and archival analysis (of development grey literature and local media). Participant observation allows for triangulating findings and exploring the gap between what people say and what they do, as well as the gap between what policies indicate and what happens in practice. The dissertation argues that official rationalities become distorted as they encounter social relations, and also that those engaged in road building must navigate complex power dynamics as they seek to enrich themselves and their families. Road development serves to reproduce existing relations of domination; resistance seems futile and is rare. At the same time, there is evidence of critique, which sometimes takes a public form, suggesting that it could become the foundation for more collective action.

Keywords: Critical Adult Education
Cultural Politics
Political Economy
Road Building
Rural Nepal
Transformative social change
Advisor: Mojab, Shahrzad Professor
Evaluation of Efficacy of Perineural Steroids and Local Anesthetics for Chronic Post-traumatic Neoropathic Pain

Trauma leading to entrapment or compression of nerves is an important cause of chronic refractory peripheral neuropathic pain (NP). The aim of this thesis was to evaluate benefits and adverse effects (AE) of administering steroids and local anesthetics around peripheral nerves subject to compression or trauma in patients with chronic peripheral NP. The first study, a systematic review and meta-analysis (SR-MA), showed a modest reduction in pain intensity based on numerical rating scale (NRS; 0-10) pain scores for patients receiving perineural steroids compared with those receiving LA or conventional medical management (CMM) (-0.69 points; 95% CI: -1.27 to -0.12; P = 0.02; I2=85%) at one to three months after the intervention. However, the quality of the studies was low. The second study was a retrospective, sequential, double cohort study in patients who sustained work-related injuries and developed trauma- or compression-related chronic peripheral NP of moderate-to-severe intensity in the ankle or the foot. In this study, the median NRS pain scores were lower in those treated by a combination of perineural local anaesthesia/steroids (LA-S) and CMM compared to those treated only with CMM [5.50(IQR 4.00-7.00) and 7.00(IQR 5.00-8.00) respectively; p

Keywords: Compression
Neuropathic
Pain
Perineural
Steroids
Trauma
Advisor: Davis, Aileen M
Three Essays on the Impact of Inducement Prizes on Innovation

Innovation prizes are an increasingly popular tool used by policy makers, firms, and non-governmental organizations to induce innovation. This is surprising given the paucity of systematic research to justify their use and empirical evidence of their impact. In this dissertation, I explore the relationship between inducement prizes and innovation and shed light on the impact of prizes on the rate and direction of innovation. In the first study, I explore whether inducement prizes increase the relative returns to research collaboration at the level of the individual researcher. I investigate how researchers’ participation in the 2005 DARPA Grand Challenge affects rates of post-prize research collaboration. Findings suggest that prize participation reduces the costs of future collaboration by incentivizing researchers to learn how to work on complex real-world problems requiring multiple domains of expertise. Increases in collaboration occur on the extensive margin (more unique coauthors) and intensive margin (more papers with existing coauthors) and persist for years after the prize, suggesting that the costs of cross-domain collaboration are fixed rather than variable. In the second study, I examine how inducement prizes influence the discovery of scientific breakthroughs. Focusing on the field of robotics research, I explore the effects of the 2005 DARPA Grand Challenge on the post-prize salience of a branch of robotics research used heavily by prize-participant teams compared to a control group of contemporaneous research in the same field but unrelated to the prize. I find that prize-relevant research experiences a disproportionate increase in forward citations after the conclusion of the prize and that prize participants’ use of a specific breakthrough technology known as the Kalman filter plays a key role driving the results. Findings suggest that in research fields where prizes provide objective benchmarks for the performance of competing approaches, they may influence the direction of research by resolving uncertainty and enabling the discovery of breakthrough ideas. In the final study, I examine the effects of multiple dimensions of team experience on performance in an annual aerospace engineering competition organized by the American Institute of Aeronautics and Astronautics. Findings suggest that experienced team leaders are most strongly related to performance and that experience at the leader and team member levels may be partial substitutes. Results also highlight that experience affects performance differently during the design phase compared to the execution phase of the competition.

Keywords: collaboration
inducement prizes
innovation
knowledge production
science policy
technological change
Advisor: Agrawal, Ajay
Essays on The Supply of Education and Student Achievement

This dissertation examines the relationship between the supply of education and student achievement in three distinct contexts and across three levels of schooling. The first chapter, Private School Entry, Sorting, and the Performance of Public Schools: Evidence from Rural Pakistan, asks whether private school expansion in rural Punjab, Pakistan, affects the academic performance of students in primary public schools. I show that younger students from wealthier households and students who perform better in school are more likely to exit public schools and enroll in private schools. I conclude that sorting does not have negative consequences for the academic performance of students who stay in public schools. The second chapter, Searching for Answers: The Impact of Student Access to Wikipedia, evaluates an intervention from a randomized controlled trial in Malawi in which secondary school students got access to Wikipedia. Students searched for information related to their school syllabus, sexuality, African news, and a variety of topics that cater to their interests. We find that access to Wikipedia improved exam scores in English and Biology, especially among low achievers. The third chapter, What Sets College Divers and Thrivers Apart: A Contrast in Study Habits, Attitudes, and Mental Health, is an article published in 2019 in Economics Letters. We examine study habits and mental health among college students in Canada. Compared to students who do very well in college, students who perform poorly struggle on several dimensions: they feel more depressed, study less, and do not utilize the free university resources. The three chapters explore the common themes of student academic performance and school resources, from primary, secondary, to tertiary education, and across three continents. The findings inform policymakers about the role of the supply of education on student achievement.

Advisor: Bobonis, Gustavo GB
The Role of Choline in Gestational Diets in the Programming of Food Intake Regulation and Metabolism in Wistar Rat Offspring

High (5-fold) folic acid (FA) diets during pregnancy result in obesity in rat offspring, associated with altered DNA-methylation of hypothalamic food-intake neurons. Like FA, the methyl-donor choline modulates fetal brain development, but its long-term programming effects on metabolic phenotype has not been reported. The hypothesis of this research is that choline in the gestational diet, like FA, is a contributor to the in utero programming of hypothalamic food intake regulation, and the later-life metabolic phenotype of male Wistar rat offspring. In study 1, Pregnant Wistar rats were fed an AIN-93G diet with recommended choline (RC, 1 g/kg diet), low choline (LC, 0.5-fold), or high choline (HC, 2.5-fold). Male offspring were weaned to a normal (16%) fat diet for 17 weeks. In study 2, the interaction between the choline content of the gestational diet (RC vs HC) and fat content of the post-weaning diet (normal (16%) vs high (45%)) on metabolic phenotype of male Wistar rats was assessed. In study 3, pregnant Wistar rats were fed an AIN-93G diet with recommended choline and FA (1X, RCRF, control), or high (5X) FA with choline at 0.5X-(LCHF), 1X-(RCHF), or 2.5X-(HCHF). Male offspring were weaned to the control diet for 20 weeks. In study 1, choline content in the gestational diet (below or above recommended intakes) programmed changes in food intake, body weight, energy expenditure and hypothalamic energy-regulatory neuropeptides. In study 2, choline additions reduced long-term body weight-gain and improved the later-life metabolic phenotype of offspring fed a high fat, but not a normal fat, post-weaning diet. In study 3, high gestational choline reduced high FA induced increases in long-term food intake and body weight and modified expression of regulatory genes in the hypothalamus. In studies 1 and 3, both early and later-life brain and plasma 1-carbon metabolites were affected by the choline content in gestational diets. In conclusion, maternal choline contributes to the in utero programming of hypothalamic food intake regulation and the metabolic phenotype of male rat offspring, and its effects are dependent on the composition of the gestational and post-weaning diets.

Keywords: Choline
Fetal Programming
Folic Acid
Hypothalamus
Maternal Nutrition
Obesity
Advisor: Anderson, Harvey
Mechanical Measurement and Stimulation of Human Pluripotent Stem Cell-Derived Cardiomyocytes

The emerging heart-on-a-chip platforms are promising approaches to establish cardiac cell/tissue models in vitro for studying cardiac physiologies, disease modeling, cardiotoxicity testing, and therapeutic discoveries. Challenges still exist in realizing the capability of sensing and evaluating the functional properties of cardiac cell/tissue models in situ (i.e., on the platforms). In particular, generating sufficient forces of contraction during the rhythmic beating of cardiomyocytes plays a central role in pumping oxygen-rich blood through the circulatory system. Developing new platforms and technologies to assess the beating behaviors and contractile functions of in vitro cardiac models is essential to provide information on cell/tissue physiologies, drug-induced inotropic responses, and mechanisms of cardiac diseases. This thesis focuses on developing biosensing technologies/platforms for the measurement of contractile functions of in vitro cardiac models. In vitro cardiac cell/tissue models were established by using Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes (iPSC-CMs) generated with the human proteome to avoid the potential species-dependent differences. Firstly, a label-free imaging technique was developed to offer a cytotoxic-free method for long-term measurement of dynamic beating trajectories, beating amplitude, beating propagation, and conduction velocities of cardiomyocyte monolayers, avoiding the perturbation and cytotoxicity induced by fluorescent dyes. Next, a carbon-based biosensing platform integrated with flexible biosensing components was developed for continuous measurement of multiple parameters of cardiac functional properties in vitro, including contractility, beating rate, beating rhythm, and field potential. In addition, a microdevice array integrated both contraction sensing and mechanical stimulation functions was also developed to recapitulate the mechanical microenvironment of myocardium in vitro and characterize the effect of mechanical strain magnitude on the maturation of iPSC-CMs. Highlighted applications and discoveries enabled by these developed platforms were summarized and discussed in aspects of investigating fundamental cardiac physiologies (e.g., iPSC-CM maturation under mechanical stimulation), drug testing (e.g., isoproterenol, verapamil, blebbistatin, and E-4031), and disease modeling (e.g., drug-induced cardiac arrhythmia and arrhythmogenic right ventricular cardiomyopathy (ARVC)).

Keywords: Biosensing platform
Conduction velocity
Contractile stress
Heart-on-a-chip
In vitro cardiac models
iPSC-cardiomyocytes
Advisor: Sun, Yu
Deep Structured Models for Spatial Intelligence

The future robots and embodied devices will seamlessly interact with the physical world, help us in our everyday lives and become an integral part of society. To make this dream come true, we need to bring spatial intelligence to our embodied devices: the ability to understand, reason, and create rich knowledge about the spatial relations among objects and space. While computer vision has significantly enhanced capabilities in 2D perception, we are still missing key ingredients to achieve the desired goal — holistic spatial modeling of our 3D world. In this thesis, we present a collection of work towards this goal. The core idea is to build expressive representations of the world and exploit rich structure in the problems. Our research efforts span both creating new structured models as well as developing novel solutions to various applications. The effectiveness of our integrated approach has been demonstrated at the full spectrum of spatial intelligence tasks, including localization, perception, and mapping. Finally, I will give a brief personal outlook on open research topics towards achieving spatial intelligence.

Keywords: Deep Learning
Localization
Mapping
Perception
Spatial lntelligence
Structured Models
Advisor: Urtasun, Raquel
Canadian Post-secondary Institutional Response to Students’ Off-campus Behaviour

This study sought to explore how Canadian post-secondary institutions [CPIs] address students’ off-campus behaviours [OCBs]. Findings were generated through document analysis of 41 Student Codes of Conduct [SCCs], an examination of four relevant illustrative cases, and semi-structured interviews with five CPI administrators responsible for student discipline. These three sources were then triangulated for further analysis and consideration of key research questions. My original contribution to the research phenomenon is to present an informed understanding of how SCCs are used at CPIs in the context of five participating institutional key informants’ responses to incidents of student OCBs. This research also examined the legitimacy and authority of CPIs institutional responses to alleged instances of student misbehaviour which occur off-campus in four illustrative case studies.Key findings revealed that SCCs varied widely in terms of their scope and authority. While some do acknowledge OCBs as meriting administrative response, a clear connection to the CPI is needed to enact such a response. In the illustrative case studies this was also seen in how the CPI administrators determined how and when to respond to students’ OCBs. Interviews with key informants echoed this need to determine each act of misconduct as a standalone case and to determine best outcomes with taking what external parties may view as extreme measures. In all three data sets, specific processes of progressive discipline were taken to enforce ‘perceived’ fairness for all parties involved. The four illustrative cases also highlighted both the use of SCCs and the administrative response to students’ OCBs in that procedural fairness is not always framed in the same manner nor are policies implemented with universal use in that policy revision and reimplementation is often incited by significant occurrences of student misconduct. As such, consideration was given to the cyclical nature of policy design and implementation in addressing the research phenomenon. Implications of the findings include a consideration of additional areas of research study such as meta-analysis of SCCs, intersectionality of CPI administrators and potential expansion of scope and authority of CPIs as online and remote learning expands.

Keywords: educational administration
higher education
institutional response
off-campus behaviour
perceived fairness
student discipline
Advisor: Janzen, Katharine
Modelling the impact of changes in education requirements on nurses’ labour market outcomes

Provinces across Canada, with the exception of Québec, have changed their Entry-to-Practice (ETP) requirements for Registered Nurses (RNs) from a diploma to a baccalaureate degree in nursing. The variation in introduction of the RN ETP requirement across Canada was used to investigate its impact on RNs’ probability of participation in the nursing labour force (relative to non-nursing employment and being ‘unemployed/out of the labour force/retired’), wages, and choice of care sector of employment. Licensed Practical Nurses (LPNs) simultaneously experienced a change in ETP requirement. LPNs’ labour market outcomes were also examined because LPNs are thought to offset changes in RNs’ labour force participation. Nurses’ outcomes were modelled using a nationally representative longitudinal dataset that captures nurses between 1996 and 2010, allowing for unobserved heterogeneity to correlate with the covariates. I found that the change in RN ETP requirement did not impact RNs’ or LPNs’ participation in the nursing labour force; however, RNs’ and LPNs’ probabilities of non-nursing employment and being ‘unemployed/out of the labour force/retired’ were impacted. The change in the RN ETP requirement did not impact RNs’ average wage and had no differential effect between diploma and baccalaureate RNs and between newly trained and experienced nurses. LPNs’ average wage across the country decreased post-changes in the RN ETP requirement. On the other hand, the change in the LPN ETP requirement did not impact RNs’ and LPNs’ average wage; however, newly trained baccalaureate RNs faced a wage decrease after changes in the LPN policy. The change in the RN ETP requirement had no effect on RNs’ and LPNs’ choice of care sector of employment. Relative to diploma RNs, baccalaureate RNs’ probability of working in the community sector increased after changes in the LPN ETP requirement. The likelihood of LPNs working in hospitals increased as their probability of working in the community decreased after the change in their ETP requirement. Jurisdictions should consider the labour market impact of changes in ETP requirement on targeted as well as non-targeted nursing categories, and the potential impact on a range of nurses’ labour market outcomes.

Keywords: Entry-to-practice Requirement
Labour Supply
Nurse
Participation
Sector of Employment
Wage
Advisor: Laporte, Audrey
Deber, Raisa