VictorJuiz/thesis huggingface dataset:
Novel MEMS Grippers for Pick-place of Micro and Nano Objects
Keywords: Micromanipulation
Microgrippers

Physical pick-and-place promises specificity, precision, and programmed motion, a feature making microrobotic manipulation amenable to automation for the construction of microsystems. Despite the significant progress made, a long-standing difficulty is the release of micro objects from the end effector due to strong adhesion forces at the micro scale. This research focuses on the development of microelectromechanical systems (MEMS) based microgrippers that integrate an active release mechanism for pick-and-release micromanipulation. The performance was experimentally quantified through the manipulation of 7.5-10.9µm glass spheres, and for the first time, achieves a 100% success rate in release (based on 700 trials) and a release accuracy of 0.45±0.24µm. Example patterns were then constructed through automated microrobotic pick-and-place of microspheres, achieving a speed of 6sec/sphere. To further miniaturize the devices for nanomanipulation, a novel fabrication process was developed. Through the manipulation of 100nm gold nano-particles inside a scanning electron microscope (SEM), preliminary demonstrations were made.
Central Nervous System (CNS) Nutrient Sensing in Diabetes
Keywords: Diabetes
Glucose Production
Hypothalamus
Rodent

An acute increase in hypothalamic glucose and its downstream metabolite lactate lower glucose production (GP) and plasma glucose (PG) levels in normal rodents. However, the effectiveness of this nutrient-sensing mechanism in metabolic disease is unknown. We assessed the effects of intracerebroventricular (i.c.v.) or intra-hypothalamic glucose and lactate on in vivo glucose kinetics in conscious rats. Study I revealed that i.c.v. lactate lowered PG via a suppression of GP in rodents with uncontrolled diabetes and diet-induced insulin resistance. Study II demonstrated that i.c.v. glucose was ineffective at suppressing GP in uncontrolled diabetic rodents or rodents with a prior 24 h whole-body or hypothalamic hyperglycemic insult. When PG levels per se were normalized in diabetic rodents hypothalamic glucose sensing to lower GP was rescued. As such, sustained hyperglycemia per se impairs hypothalamic glucose effectiveness in diabetes. Further studies are necessary to determine defective mechanisms upstream of lactate metabolism hindering CNS glucose sensing.
Syntaxin-1A Inhibits Cardiac ATP-Sensitive Potassium Channels by Direct Interaction with Distinct Domains within Sulphonylurea Receptor 2A Nucleotide-Binding Folds
Keywords: Syntaxin-1A
ATP-sensitive potassium channel
sulfonylurea receptor
SNARE
Kir6.2
SUR2A

KATP channels couple cell metabolic status to the membrane excitability by sensing the cytoplasmic ATP/ADP ratio. Present studies examined how conserved motifs (Walker A (WA), signature sequence (L), and Walker B (WB)) within each NBF of SUR2A bind to Syn-1A to affect its actions on cardiac KATP channels. In vitro binding experiments illustrated that Syn-1A binds cardiac SUR2A at WA and L of NBF-1 and WA, L, and WB of NBF-2. Electrophysiology experiments on stably expressing SUR2A/Kir6.2 cell-lines showed that only L and WB of NBF-1 and all three NBF-2 motifs could abrogate the inhibitory effect of Syn-1A on SUR2A/KATP channels. These results lead me to hypothesize that more independent motif in NBF-2 can bind and abrogate Syn-1A’s inhibition than NBF-1 on SUR2A/KATP channels. A corollary postulate is that Syn-1A acts as a scaffold to secure the NBF-1 and -2 in dimer conformation required for SUR2A to modulate Kir6.2 gating.
Syntaxin-1A Inhibits the KATP Channel Through Interaction with Distinct Sites Along the Nucleotide-binding Folds of Sulfonylurea Receptor 1
Keywords: Syntaxin-1A
KATP
nucleotide-binding folds
ATP/ADP

The KATP channel is a key regulator of the pancreatic β-cell, effectively linking metabolic status to electrical activity. Syntaxin-1A has been previously reported by our lab to both bind and inhibit the KATP channel via the nucleotide-binding folds (NBFs). The purpose of this thesis project was to elucidate the precise regions within the NBFs responsible for the Syn-1A- KATP interaction. In vitro binding assays revealed that Syn-1A associates with the Walker domains of both NBF1 and NBF2. Furthermore, site directed mutagenesis of the conserved lysine in Walker A of both NBFs abolishes Syn-1A affinity for this region. Electrophysiological recordings indicate that channel inhibition was mediated primarily through interaction with NBF1-Walker B and both Walkers of NBF2. Based on these results, we propose a model by which Syn-1A acts as an inhibitory clamp on the KATP channel, effectively buffering minor fluctuations in ATP/ADP concentration to prevent unnecessary channel activity.
Circuit Debugging with Error Trace Compaction and Maximum Satisfiability
Keywords: Circuit Debugging
Formal Methods

Improving the performance and functionality of contemporary debugging tools is essential to alleviate the debugging task. This dissertation aims at narrowing the gap between current capabilities of debugging tools and industry requirements by improving two important debugging techniques: error trace compaction and automated debugging. Error trace compaction leverages incremental SAT and heuristics to reduce the number of clock cycles required to observe a failure in an error trace. The technique presented reduces the length of the error trace to a minimum while improving performance by 8× compared to a previous technique. The second contribution uses maximum satisfiability to enhance the functionality and performance of automated debuggers. The method proposed can identify where in the design the bug is located and when in the error trace the bug is excited. Compared to a competitive SAT-based approach, our formulation produces problems that are 80% smaller and that can be solved 4.5x faster.
Modeling of an Electrochemical Cell
Keywords: Electrochemical Cell
Electrochemical Capacitor
Supercapacitor
Ultracapacitor
Modelling

This thesis explores a rigorous approach to model the behaviour of an electrochemical cell. A simple planar electrochemical cell consisting of stainless steel electrodes separated by a sulfuric acid electrolyte layer is modeled from first principles. The model is a dynamic model and is valid under constant temperature conditions. The dynamic model is based on the Poisson-Nernst-Planck electrodiffusion theory and physical attributes such as the impact of nonlinear polarization, the stoichiometric reactions of the electrolyte and changes to the transport coefficients are investigated in stages. The system of partial differential equations has been solved using a finite element software package. The simulation results are compared with experimental results and discrepancies are discussed. The results suggest that the existing theory is not adequate in explaining the physics in the immediate vicinity of the electrode/electrolyte interface even though the general experimental and simulation results are in qualitative agreement with each other.
Determination of the Role of Synapse Associated Protein 97 (SAP97) in the Normal and Parkinsonian Striatum
Keywords: Parkinson's
SAP97
6-OHDA-lesioned
striatum

Parkinson’s disease (PD) is a debilitating movement disorder associated with the death of dopaminergic nigrostriatal neurons. In addition to dopamine deficiency, abnormalities in glutamate and other receptors at striatal synapses have been reported. Synapse associated protein 97 (SAP97) is involved in regulation of glutamate receptor function. In the striatum of unilaterally-lesioned 6-OHDA rat model of PD, SAP97 levels are decreased in post synaptic density fraction, as well as in the whole striatum. I hypothesize that changes in striatal levels and subcellular distribution of SAP97 are responsible for abnormal neurotransmission in striatum and the motor symptoms of PD. GFP-tagged wild type SAP97 and SAP97 mutants were over-expressed in the striatum of 6-OHDA-lesioned rat model of PD. A single 6.5 mg/kg dose of L-DOPA eliminated parkinsonism in 6-OHDA-lesioned rats over-expressing SAP97-GFP, whereas, three 6.5 mg/kg doses of L-DOPA negated parkinsonism in 6-OHDA-lesioned rats over-expressing SAP97-GFP and SAP97∆1-65-GFP. The over-expression of SAP97∆1-65-GFP enhanced parkinsonism in 6-OHDA-lesioned rats and blocked the antiparkinsonian effect of L-DOPA.
The Protein Interactions and Functions of Transient Receptor Potential Melastatin 7 (TRPM7) Ion Channel
Keywords: Protein Interactions
TRPM7

Ion channels are proteins that facilitate ion diffusion across cell membrane. Nevertheless, various groups of ion channels can act as surface receptors and play important roles in signal transduction. Transient Receptor Potential Melastatin 7 (TRPM7) ion channel has been implicated in diverse cellular functions including actomyosin cytoskeletal remodeling and anoxic neuronal death. However the mechanisms behind TRPM7’s physiological roles remain undetermined. TRPM7 possesses unusually long intracellular domains and a functional C-terminal alpha kinase domain that may contribute to regulation of channel activity and signal transduction. We therefore identified proteins that interact with TRPM7 C-terminus. Pull-down assays coupled with LC-MS/MS revealed that cytoskeletal proteins (actin and tubulin) and synaptic vesicle proteins (VAMP2 and SNAP25) associate with the TRPM7. In addition, we further found that TRPM7 does not directly bind microtubules or single dimeric tubulin subunits. Thus one or more microtubule binding proteins is involved in the association between TRPM7 and microtubules.
Coating Collagen Modules with Fibronectin Increases in vivo HUVEC Survival and Vessel Formation through the Suppression of Apoptosis
Keywords: modular tissue engineering
endothelial cells
apoptosis
extracellular matrix
fibronectin

Modular tissue engineering is a novel approach to creating scalable, self-assembling three-dimensional tissue constructs with inherent vascularisation. Under initial methods, the subcutaneous implantation of human umbilical vein endothelial cell (HUVEC)-covered collagen modules in immunocompromised mice resulted in significant host inflammation and limited HUVEC survival. Subsequently, a minimally-invasive injection technique was developed to minimize surgery-related inflammation, and cell death was attributed to extensive apoptosis within 72 hours of implantation. In confirmation of in vitro results, coating collagen modules with fibronectin (Fn) was shown in vivo to reduce short-term HUVEC apoptosis by nearly 40%, while increasing long-term HUVEC survival by 30% to 45%. Consequently, a 100% increase in the number of HUVEC-lined vessels was observed with Fn-coated modules, as compared to collagen-only modules, at 7 and 14 days post-implantation. Furthermore, vessels appeared to be perfused with host erythrocytes by day 7, and vessel maturation and stabilization was evident by day 14.
Evaluating the Efficiency, Usability and Safety of Computerized Order Sets in Sunnybrook Health Sciences Centre's Computerized Provider Order Entry System
Keywords: CPOE
Human Factors
Usability

Few studies examine technical barriers, such as usability, to successful Computerized Provider Order Entry (CPOE) system implementation. This thesis explores this literature gap through the evaluation of the Sunnybrook CPOE order set system with a heuristic evaluation of the Sunnybrook CPOE system, the development of a more user friendly CPOE order set interface (Test Design), and a usability study comparing three order set formats (Sunnybrook CPOE, Test Design, and paper order sets). A randomized trial was conducted with 27 Sunnybrook physicians at the hospital. Results showed that the Sunnybrook CPOE order set system was less efficient (task times were on average 364 seconds longer than Test Design and 344 seconds longer than paper), less user-friendly (users were less confident, less satisfied, and more frustrated with Sunnybrook CPOE tasks), and less safe than paper order sets (more harmful errors). Test Design was as efficient and safe as paper order sets.
Improving Patient Safety during Radiation Therapy through Human Factors Methods
Keywords: Radiation Therapy
Human Factors

This study aimed to apply human factors methods to identify potentially unsafe aspects of a radiation therapy delivery system at Princess Margaret Hospital, and to provide recommendations accordingly. Analyses were conducted to examine the workflow, work environment and user interfaces involved in the treatment process. Based on findings from these analyses, components of the user interface were redesigned to address some of the issues found. Sixteen radiation therapy students were then used to experimentally evaluate the redesigned interface through a usability test. Compared to the current interface, the error rates of two common errors were significantly lower, and the average task completion time was significantly shorter when the redesigned interface was used. Results from a post-test questionnaire also indicated a high degree of satisfaction with the redesigned interface. Therefore, human factors methods can be applied to evaluate and design radiation therapy systems for improved error rates, efficiency and user satisfaction.
Identification of Molecular Alterations Associated with Loco-regional and Distant Breast Cancer Metastasis
Keywords: Breast cancer
Biomarkers

Metastasis initiation is a complex process encompassing numerous steps. To identify molecular alterations associated with early and late stages of metastasis, we used high throughput screening techniques. Early events in metastasis were investigated by differential proteomic analysis of lymph node-negative and positive breast cancer samples. Two candidate biomarkers (DCN and HSP90B1) were discovered and further validated through tissue microarray analyses. To examine late events in metastasis formation, we prospectively evaluated genomic differences between disseminated tumour cells in bone marrow, and metastatic tumour cells obtained from computed tomography guided biopsies of bone metastases. Results indicate that specific subsets of genes are required for breast cancer cells to initiate bone metastases. Discovery of proteomic and genomic alterations specifically associated with metastases may yield biomarkers capable of stratifying patients into different risk categories. Proteins and genes identified in this work may form the foundation of a biomarker panel for metastatic risk assessment.
Human Rights and the War Against International Terrorism: A War Without Rights?
Keywords: international humanitarian law
international human rights law
targeted killing
terrorism

The United States has justified targeted operations against suspected terrorists as a legitimate tool in the war against terrorism. In response to international criticism that a November 2002 targeted killing operation in Yemen violated human rights standards, the US asserted that the right to life was suspended during war. While this assertion is prima facie incorrect, many legal experts, scholars and authors agree in principle that a military response to international terrorism -- along with the concomitant dilution of the right to life -- is not only appropriate, but also complies with international law. However, the modern jus ad bellum limit the circumstances in which a state may lawfully resort to armed force. A fulsome understanding of international humanitarian law and the characteristics of groups such as Al Qaeda reveals that international law does not permit states to employ their military forces to responde to the international crime of international terrorism.
Law as a Social Determinant of Unsafe Abortion in Argentina
Keywords: abortion
Argentina
Social Determinants of Health

Using Burris et al.’s model of law as a social determinant of health, this thesis postulates that the law and its application contribute to abortion-related morbidity and mortality among those women who qualify for a legal and safe abortion according to the justifications stipulated in the Criminal Code. This thesis proposes a circular model in order to show how the application of the law, through courts rulings, contributes to unsafe abortion. On the one hand, Argentine law acts as a pathway along which inequity in socioeconomic status exposes certain women to pathogenic practices, such as self-induced abortions. On the other hand, the law acts as a shaper of socioeconomic status as it perpetuates gender stereotypes, constructing a normative world where sex-role stereotypes are naturalized, and having an impact in women’s lack of access to legal and safe abortions.
Women's Reproductive Health Rights: The Rule of Law and Public Health Considerations in Repealing the Criminal Laws on Abortion in the Republic Suriname
Keywords: abortion
reproductive health rights
reproductive health law
reproductive health
women's rights
right to health
crime and punishment approach
human rights
right to life
rule of law
Convention on the Elimination of All Forms of Discrimination against Women
International Covenant on Economic, Social and Cultural Rights
Suriname
criminal law
pregnancy
constitutional law
Convention on the Rights of the Child
American Convention on Human Rights

Within the Surinamese jurisdiction the Constitution grants women the right to health and imposes a legal duty on the state to facilitate the realization of this right. Also treaty law, in particular, the ICESCR article 12 and the CEDAW article 12 grant women the right to the highest attainable standard of health and the right to non-discriminatory access to healthcare. But due to the criminal law applicable to abortion women lack non-discriminatory access to reproductive healthcare and therefore do not enjoy the highest attainable standard of pregnancy related health. Despite its decision not to enforce the abortion prohibiting criminal laws, Suriname remains in a state of failure to comply with its legal duties as imposed by the Constitution and treaty law. This, due to the state’s reluctance to repeal the criminal laws on abortion and its failure to enact effective health regulations to facilitate women in need of an abortion.
An Objective Methodology to Assess Visual Acuity Using Visual Scanning Parameters
Keywords: Point of Gaze Estimation
Visual Acuity

An objective methodology to assess visual acuity (VA) in infants was developed. The methodology is based on the analysis of visual scanning parameters when visual stimuli consisting of homogeneous targets and a target with gratings (TG) are presented. The percentage of time on the TG best predicted the ability of the subject to discriminate between the targets. Using this parameter, the likelihood ratio test was used to test the hypothesis that the TG was discriminated. VA is estimated as the highest spatial frequency for which the probability of false positive is lower than the probability of false negative for stimuli with lower spatial frequencies. VA estimates of 9 adults had an average error of 0.06 logMAR with a testing time of 3.5 minutes. These results suggest that if the attention of infants can be consistently maintained the new methodology will enable more accurate assessment of VA in infants.
Metal and Polymer Foam Hybrid Materials: Design, Fabrication and Analysis
Keywords: Hybrid Materials
Micro-truss
Sandwich cores
Polymer Foam

Two novel hybrid materials for use in sandwich cores of structural materials are designed, manufactured and mechanically tested. Each material is a hybrid of metal and polymer foam. One set of hybrids is fabricated using an aluminium micro-truss filled with varying densities of polyurethane foam. Increases up to 120% in stiffness, 372% in strength, 740% in resilience and 106% in impact energy over the aluminium micro-truss are obtained from compression and impact testing. Furthermore, the stiffness of these hybrids can be tailored according to the density of the polyurethane foam. Another set of hybrids is fabricated using a rapid prototyped ABS polymer truss that is foamed and electroplated with nanocrystalline nickel. Increases up to 1525% in stiffness, 1165% in strength and 650% in energy absorption over the foamed ABS truss are obtained. Furthermore, the gain in strength, stiffness and energy absorption outweigh the gain in density in these hybrid materials.
The Core Principles of Arbitral Expertise: A New Lens Through Which to View Weber v. Ontario Hydro
Keywords: Labour Law
Industrial Relations

This thesis considers the substance of a labour arbitrator’s expertise. The author argues that the question is timely in that its answer provides a novel way to approach the position the Supreme Court of Canada has taken with respect to an arbitrator’s rightful jurisdiction, most notably in the over-decade old decision of Weber v. Ontario Hydro, a decision which continues to act as a thorn in arbitrators’ sides.
Natural Health Products (NHPs) and Canadian Pharmacy Students: Core Competencies
Keywords: pharmacy
education
natural health products

Objective: To reach consensus on entry-to-practice natural health product (NHP)-related competency statements for Canadian pharmacy students. Methods: Four rounds of a modified Delphi method were conducted. Participants; pharmacy educators,and representatives from Canadian pharmacy organizations (n=17), ranked their level of agreement using a 5-point Likert scale. Results: Consensus occurred when all participants ranked a statement 4 or 5. Three core NHP-related competencies were identified: 1) the ability to incorporate NHP knowledge when providing pharmaceutical care; 2) the ability to access and critically appraise NHP-related information sources, and 3) the ability to provide appropriate education to patients and other health care providers on the effectiveness and potential adverse effects and drug interactions of NHPs. Two additional NHP-related competency statements emerged as important, but consensus was not achieved. Conclusions: If the developed core NHP-related competency statements are widely implemented, Canadian pharmacists will be able to fulfill their NHP-related professional responsibilities upon entry-to-practice.
Homeostatic Beliefs: Measurement and Future Applications
Keywords: Beliefs
Scale validation

“Homeostatic beliefs” (HBs) denote a sense that one’s life path will remain stable in the long-term despite short-term disruptions. Two studies have been undertaken to explore whether HBs exist independent of other constructs, and to develop a scale with which to measure them. In Study 1, 158 undergraduate students completed a draft HB scale and theoretically related scales. Convergent and divergent validity were assessed with correlational and regression analyses: HBs are most strongly related to, but not redundant with, optimism, trait extraversion, and satisfaction with life. Using exploratory factor analysis, a six-item HB scale was derived. Study 2 is in progress, and will assess the construct validity of the HB scale by attempting to manipulate HBs to possibly influence individuals’ reactions to a mortality salience manipulation. We hypothesize that high HBs may buffer individuals from transient disrupting stimuli such as a mortality salience cue.