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Out of Sight, Out of Mind: An Analysis of Immigration Detention Practices in Canada and Germany
Get PDFInternational criticisms from human rights activists on a variety of matters related to Canada and Germany’s immigration detention frameworks illuminate the need for an examination of human rights impacts. This thesis explores the legal framework that allows for immigration detention and hopes to draw attention to and shed light on problems in the immigration detention frameworks identified in the literature. Through a qualitative comparative legal content analysis of laws and policies in the two countries, insight can be gained into the similarities and differences between the two countries to ultimately provide information about, and possible solutions to, the challenges faced by policymakers in this domain. Various laws and policies that govern immigration detention in both countries will be analyzed and compared in this thesis, in order to identify key themes and answer the following research questions: 1) How does each country regulate immigration detention? (a) In what circumstances is detention lawful in each country? What makes a detention unlawful in each country? b) How does each country address the key human rights concerns identified in the literature review (namely, racial discrimination, mental health, and child detentions)? (c) What can be learned from each country to better address the human rights impacts of immigration detention? By comparing Canada and Germany, light can be shed on potential human rights issues in the immigration detention frameworks and the domestic policy reform debates in both countries can be enriched.
Faculty Supervisor: Dr. Tamara O’Doherty, School of Criminology, Simon Fraser Universit
Assessing the Ability of COVID-19 mRNA Vaccines to Elicit Antibodies Against SARS-CoV-2 Variants of Concern
Get PDFThe COVID-19 pandemic has been marked by emergence of SARS-CoV-2 variants of concern (VoC), including strains that may evade immune responses. To assess the ability of current vaccines to generate immunity against VoCs, we tested samples from 135 people after two or three vaccine doses using laboratory assays that measure the ability of antibodies to bind to the viral Spike protein and to block its interaction with the cell entry receptor, Angiotensin Converting Enzyme 2 (ACE-2). Both responses were quantified against the ancestral virus strain (Wuhan) as well as alpha, beta, gamma, delta and omicron VoCs. One month after the second vaccine dose, binding antibodies were similar against Wuhan, alpha and delta, but lower against beta, gamma and omicron (all p<0.05). Notably, ACE-2 blocking activity was lower against all VoCs at this time. Six months after the second dose, binding antibodies and ACE-2 blocking activities declined against all strains, and remained significantly lower against all VoC. One month after the third dose, binding antibodies against all strains exceeded prior peaks, but remained lower against wildtype. Similarly, ACE-2 blocking activity exceeded prior peaks, but remained lower against all VoC except delta. In summary, our results show that COVID-19 vaccines induced antibodies against all VoCs, but immune evasion was observed, particularly in the case of beta, gamma and omicron variants. Antibody responses declined significantly by six months after the second dose, but they were boosted to new peaks by a third dose.
Acknowledgments –
This project was supported by the Public Health Agency of Canada through the Canadian Covid-19 Immunity Task Force [2021-HQ-000120]. We thank the study participants, without whom this work would not have been possible. We also thank study staff at the long-term care residences, Simon Fraser University and St. Paul’s Hospital for support. A similar analysis of the Omicron strain is ongoing and will be included in our final presentation.
Faculty Supervisor: Dr. Mark Brockman, Faculty of Health Sciences, Simon Fraser Universit
Sleep, Mental Health and Cognitive Performance of Young Adults
Get PDFSleep disturbance may be an early sign for more serious mental health issues and early detection and intervention could prevent prodromal symptoms of disorders from manifesting. The current study aims to identify what cognitive tests are sensitive to sleep-dependent cognition. The study will also examine if scores on mental health assessments are associated with sleep measures to further understand the associations between sleep, mental health and cognitive performance. Undergraduate university students (18 to 30 years of age) will complete seven days of remote sleep monitoring using an actigraphy watch and daily sleep diary methods. They will then return to the lab on day seven to complete cognitive testing and mental health questionnaires. This is an exploratory pilot study, which will inform future experimental designs. A correlation matrix will be used to examine the relationships between sleep quality and quantity (total sleep time, sleep onset latency, sleep efficiency, sleep waking and wake after sleep onset), depressive and anxiety symptoms and scores on cognitive tests. Cognitive tests that specifically target processes that depend on neurogenesis (the production of new brain cells) are predicted to be uniquely sensitive to sleep disturbance due to the associations between sleep disturbance and reduced neurogenesis. If cognitive tests that are sensitive to sleep-dependent cognition are found, then they could be used in clinical settings to identify patients with sleep disturbance who may benefit from sleep interventions.
Faculty Supervisor: Dr. Brianne Kent, Department of Psychology, Simon Fraser Universit
Design, Synthesis, and Characterization of a New Piezo-/Ferroelectric Perovskite Solid Solution with High Curie Temperature.
No full textPiezoelectricity is the ability of a material to convert mechanical energy into electrical energy and vice versa. Piezoelectric materials are widely used as transducers in medical ultrasound imaging because they are able to act both a transmitter (electrical energy to sound wave) and receiver (echo soundwave to electrical signal).
The piezoelectric effect is also harnessed in self-powered devices, such as sensors, because they are able to run on “waste” vibrational energy generated as a by-product. For example, a pump vibrates constantly while operating, this vibrational energy is sufficient to power a piezoelectric sensor, allowing for real time monitoring without the need for a battery or external energy source.
My project involves the synthesis and characterization of a piezoelectric material with a high Curie temperature, meaning that it retains its piezoelectric properties above 200OC. In my presentation I will detail my research on the modification of a known high temperature piezoelectric material, BiScO3-PbTiO3. I will show how its piezoelectric properties can be enhanced by integration of Bi(Zn1/2Ti1/2)O3 into the structure, resulting in a promising candidate for high temperature applications.
Faculty Supervisor:Dr. Zuo-Guang Ye, Department of Chemistry, Simon Fraser University
Compiling Fault-Tolerant Quantum Programs with Lattice Surgery
No full textOur project, the Lattice Surgery Compiler (LSC) aims to build a compiler that translates quantum programs, expressed as quantum circuits, to a format designed to express error corrected computations. As output of the compiler, we target a set of instructions known as lattice surgery. Lattice surgery is a way of manipulating a very large lattice of quantum units (qubits) arranged so that the computation content is more resistant to errors.
Building this compiler presented us with scientific and engineering challenges. We use results from the field of quantum information to process the computation, we solve technical problems such as parsing the assembly language of quantum programs and deal with the engineering challenge of putting together a complex compilation pipeline. Finally, aiming to make our project accessible to a wide audience of researchers, we save users the trouble of installing the large software stack needed to run the compiler by hosting it as website at https://latticesurgery.com.
Faculty Supervisor:Dr. Steven Pearce, School of Computing Science, Simon Fraser University
Research Team Members:Hoi-Kwan Lau, Department of Physics and Alex Nguyen, Simon Fraser Universit
The association between coffee consumption and type 2 diabetes in women
Get PDFDiabetes is a worldwide chronic disease that affected many people’s lives, it is a preventable disease that has a great association with people’s lifestyles and diets. Coffee was a common beverage that emerged in people’s lives and was favoured by many people. With the popularity of coffee, the health effects of drinking coffee are also taken into account in many research studies. The article investigates whether the consumption of coffee will reduce the risk of Type 2 diabetes among women to fill the gap of specific sex studies. Three studies were examined and compared to support the idea that coffee consumption lowered the risk of type two diabetes in women.
Biotic resistance on muddy shores? Non-parasitic native barnacles parasitise a non-native snail
Get PDFPeople have moved marine species around for centuries, and the rate of ecologically damaging introductions is accelerating. The success of an introduced species is determined by the characteristics of that organism, but also by the features of the species in the recipient habitat. ‘Biotic resistance’ can arise when native species slow down or prevent the spread of introduced species through parasitism, predation, and/or competition. Here, we examine if native barnacles that grow on the mudsnail Batillaria attramentaria offer biotic resistance against this invader from the western Pacific. We conducted population surveys, mark-recapture experiments, and behavioural observations at Crescent Beach, BC, to measure the effects of barnacles on movement, growth, and short-term survival of mudsnails. Approximately one-third of mudsnails carried barnacles, the weight of which sometimes exceeded the weight of the mudsnail. Barnacle presence decreased the likelihood that mudsnails would move, and barnacle weight reduced the distance moved. The higher the ratio of barnacle weight to snail weight, the lower the likelihood of mudsnail movement and distance moved, which could have implications for foraging success of mudsnails carrying barnacles. Shell weight and shell length were highly correlated, but the slope of the relationship was similar for mudsnails with and without barnacles. There was no effect of barnacle presence on mudsnail survival. Overall, native barnacles appear to offer some, though weak, biotic resistance to invasive mudsnails. Discovering that native species can hinder important attributes of invasive species, such as movement, helps us further understand the ability of ecosystems to resist invasion.
Faculty Supervisor: Dr. Isabelle Côté, Department of Biological Sciences, Simon Fraser Universit
Sex-dependent effects of preeclampsia on birthweight and mortality.
Get PDFPreeclampsia is a disorder that affects 2-10% of pregnancies, and Canadian studies have found that the incidence of preeclampsia is increasing. While preeclampsia is diagnosed and defined by symptoms present in the mother, it is associated with lower infant birthweights, due to nutrient deprivation throughout pregnancy. Infants with lower birthweights for their gestational age have higher risks of type 2 diabetes and cardiovascular disease, and higher lipid levels throughout their lifetimes, along with many other risk factors. These long-term impacts of low birthweight make the study of factors that are known to impact birthweight, such as preeclampsia, important not just for infant health but in understanding health throughout the lifespan. I will study the birthweights of infants born to mothers with preeclampsia, compared to infants without any chronic challenges while in utero. The American CDC database has open-source data on every birth in the United States since 1968, and I will use data from a subset of years, with a sample size of approximately 40,000 births per year after exclusions. I will also compare mean birthweights by sex, to determine if one sex is more affected by preeclampsia. Additionally, I will be studying mortality, to see if infants born to mothers with preeclampsia are more at risk of certain causes of death, and if this is sex-dependent. This population-level retrospective study will allow us to learn more about the impact of preeclampsia on infant birthweight, which can serve as a long-term component of health, and on infant mortality.
Faculty Supervisor: Dr. Julian Christians, Department of Biological Sciences, Simon Fraser Universit
Sleep Deprivation and Motor Learning
Get PDFIt is well-established that sleep is important for learning and memory. The goal of our project is to assess how the impact of acute sleep deprivation in mice affects learning two motor learning tasks: the reaching task and ladder rung walking test. For the reaching task, a mouse is placed in an apparatus and must learn to reach through a narrow opening for a food reward. For the ladder rung walking test, a mouse is placed in a narrow corridor and must learn to walk across a ladder to their home cage. This task assesses walking, limb placement, and inter-limb coordination. Our hypothesis is that mice that are allowed to sleep following a learning session will perform better the following day, compared to mice who are sleep deprived following a learning session. To prevent the mice in the sleep deprivation group from sleeping, they will be gently poked with paintbrushes if behavioural signs of sleep are observed. To our knowledge, no previous research has assessed how learning these tasks is affected by sleep deprivation. We intend to inform future studies of sleep deprivation and motor learning that will use EEG to study what is happening in the brain during sleep that is important for learning.
Faculty Supervisor: Dr. Brianne Kent, Department of Psychology, Simon Fraser Universit
Alternative Methods for Chipping in Golf
Get PDFChips are golf shots from outside the green, usually performed with a high-lofted club (a “wedge”), that require relatively low impact forces but high accuracy. Golfers who have physiological tremors such as focal dystonia may experience jerky hand motions that can ruin a chip. We propose two alternative chipping methods that may reduce the negative impact of tremors: using a less-lofted “hybrid” club with the golfer’s preferred grip and using a hybrid club with a novel arm-lock grip. Hybrid clubs make the ball land sooner and roll more, while the arm-lock grip reduces wrist movements and utilizes shoulder and upper arm muscles that are less affected by tremors. We hypothesize that these hybrid options, not normally considered by golfers, may improve the chipping performance of golfers affected by tremors as well as golfers not affected by tremors. To test our hypotheses, we will recruit 64 experienced golfers, 32 with tremors and 32 without. Within each group we aim to recruit eight participants in four sub-categories: young female (18-44); young male (18-44); senior female (45+); and senior male (45+). We will evaluate accuracy from measuring the final ball resting positions from 120 chips aimed at four standard targets. We will compare accuracy within each participant and across groups and determine whether differences emerge when using the wedge vs. hybrid and the two grip methods. Additionally, to elucidate the biomechanical basis of any performance differences, we will analyze swing kinematics data generated by a wireless motion capture sensor and computer vision tools.
Faculty Supervisor: Dr. Andy Hoffer, Biomedical Physiology and Kinesiology, Simon Fraser University
Research Team Members: Pawel Kudzia, Simon Fraser Universit