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Neuropeptides are central modulators of many functions including male-specific mating behaviours. Understanding how these chemical messengers modulate the neural substrates are still not well understood but remains important for biological research. In Drosophila melanogaster, two well-defined microcircuits (Longer-Mating-Duration (LMD) and Shorter-Mating-Duration (SMD)), are used to understand the underlying mechanisms of how neuropeptide interactions modulate temporal information in mating behaviours. In our study, we investigated the influence of SIFamide receptor-mediated signaling and its association to both LMD and SMD. We performed several RNAi-based screens where we identified and mapped out seven different types of neuropeptidergic neurons which were found to be important to either LMD and/or SMD. Following this analysis, we highlight three independent signaling pathways which are necessary to describe the cellular mechanics of the neuropeptides involved. Firstly, we infer that synaptic contacts between proctolin and SIFamide neurons in the subesophageal ganglion mediate inhibition in SMD whereas proctoclin as a neuropeptide modulates both LMD and SMD in a non-synaptic manner. Secondly, we describe an existing insulin-related microcircuit that is modulated by the inputs of Dimmed (DIMM), a transcription factor, through adipokinetic hormone, allatostatin A, and leucokinin to exhibit SMD. Thirdly and lastly, we discuss our interpretations of how capability neurons in the central brain resolves a potential disinhibition microcircuit in LMD via olfactory based signaling in the antennae lobe. In summary, our results contribute to establishing a model system to study neuropeptidergic microcircuits in complex mating behaviours.
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Site layout planning (SLP) is an essential step for having a productive, efficient and safe construction environment. A well-planned construction site helps in increasing the productivity and safety of the construction operations and in reducing the overall cost and duration of the project. The main purpose of SLP is to manage the available spaces on the construction site and to select the most appropriate location for the temporary facilities (TF) needed to complete the project by taking into consideration all the existing constraints between the different TFs and their relationships to the permanent facilities (PFs). Due to its complexity and the wide range of factors and variables included in the site layout planning process, the models discussed in the literature vary in their scope, objectives, and approaches to providing a solution for site layout planning, which decreases the opportunities for studies to build upon each other towards achieving a versatile model to tackle a variety of issues associated with SLP. In general, despite the vast contributions to the site layout planning field of the models found in the literature, there is still room for improvement by fulfilling some neglected requirements and including some functions that are useful in any site layout planning model, which the integration of Building Information Modeling (BIM) with Geographic Information System (GIS) can provide. This thesis presents a methodology for developing a model for site layout planning based on the integration of BIM with GIS in an attempt to develop a versatile and flexible solution (model) to help professionals during the SLP process. This model will support the decisions of planners during the SLP process and allow them to apply their knowledge in planning and designing, in an efficient and timely manner, a construction site that is safer, more efficient and keeps potential conflicts to a minimum. The research methodology includes a comprehensive literature review, collecting all the necessary data related to SLP, PF and TF, model development and implementation. The presented model is designed in a modular format and consists of six modules, 1) a 3D modeling module; 2) a route planning and hauling (RPH) module; 3) an execution schedule time entry (ESTE) module that facilitates the daunting and time-consuming process of creating a 4D model; 4) a 4D modeling module that simulates the progress of construction and helps in placing TFs on the right locations on site; 5) a temporary facilities library (TFL) module, which is developed to facilitate selecting TFs, modeling and placing TFs onsite, and planning the construction site; and 6) a rule-based dynamic conflict detection (DCD) module that detects conflicts and clashes in 2D and 3D and then notifies users about the detected conflicts through various feedback including visual, textual, and tabular, all in one data-rich environment. Also, the presented model will provide users with spatio-temporal analysis and data management capabilities. The successful implementation of this methodology contributes in developing a versatile and flexible SLP model that will provide users with the essential requirements and functions they need for SLP, which can be enhanced and extended to include more modules and functions through further research in this area.
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In Canada, parole has become increasingly difficult to obtain over the last several decades. This resistance is arguably rooted – at least partially – in a number of high-profile parole violations and changes to both the laws and practices governing parole that are almost certainly a reflection of wider fear of crime and the rise of the risk society. This increased difficulty in obtaining parole should be seen as a concern (rather than the correct or most appropriate response) given that parole is believed to be a major step in the successful reintegration of offenders into the community (Parole Board of Canada, 2016). Within this context, it is intriguing to note the very recent increase in the use of parole in Canada. However, there has been very little academic research conducted to explain or understand this new phenomenon. Given that actual policies and practices governing parole are often influenced by public opinion/attitudes (Roberts, Stalans, Indermaur, & Hough, 2003), one possible explanation may reside in the current knowledge/perceptions of parole held by Canadians. Unfortunately, despite earlier research (Roberts, 2004), our understanding of public attitudes regarding parole is still very limited. In particular, little is known about recent public knowledge of this correctional release procedure and perceptions regarding its use. Through the use of a survey questionnaire, this study presents an updated view of public perceptions and knowledge about parole. Further, it examines potential correlations between these two constructs. The results reveal little public knowledge of parole and generally ‘negative’ perceptions of it. Further, little evidence was found to support the notion that these current attitudes differ in any significant way from findings reported in earlier polls. In conclusion, the recent increase in the use of parole does not seem to be rooted in changes in Canadians’ knowledge or perceptions of it.
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There have been significant advances in communication technologies over the last decade, such as cellular networks, Wi-Fi, and optical communication. Not only does the technology impact peoples’ everyday lives, but it also helps cities prepare for power outages by collecting and exchanging data that facilitates real-time status monitoring of transmission and distribution lines. Smart grids, contrary to the traditional utility grids, allow bi-directional flow of electricity and information, such as grid status and customer requirements, among different parties in the grid. Thus, smart grids reduce the power losses and increase the efficiency of electricity generation and distribution, as they allow for the exchange of information between subsystems. However, smart grids is not resilient under extreme conditions, particularly when the utility grid is unavailable. With the increasing penetration of the renewable energy sources (RES) in smart grids, the uncertainty of the generated power from the distributed generators (DGs) has brought new challenges to smart grids in general and smart microgrids in particular. The rapid change of the weather conditions can directly affect the amount of the generated power from RES such as wind turbine and solar panels, and thus degrading the reliability and resiliency of the smart microgrids. Therefore, new strategies and technologies to improve power reliability,sustainability, and resiliency have emerged. To this end, in this thesis, we propose a novel framework to improve the smart microgrids reliability and resiliency under severe conditions. We study the transition to the grid-connected operational mode in smart microgrids,in the absence of the utility grid, as an example of emergency case that requires fast and accurate response. We perform a comparative study to accurately predict upcoming grid-connected events using machine learning techniques. We show that decision tree models achieve the best average prediction performance. The packets that carry the occurrence time of the next grid-connected transition are considered urgent packets. Hence, we per-form an extensive study of a smart data aggregation approach that considers the priority of the data. The received smart microgrids data is clustered based on the delay-sensitivity into three groups using k-means algorithm. Our delay-aware technique successfully reduces the queuing delay by 93% for the packets of delay-sensitive (urgent) messages and the Packet Loss Rate (PLR) by 7% when compared to the benchmark where no aggregation mechanism exists prior to the small-cell base stations. As a mitigation action of the utility grid unavailability, we use the electrical vehicles (EVs) batteries as mobile storage units to cover smart microgrids power needs until the utility grid recovery. We formulate a Mixed Integer Linear Programming (MILP) model to find the best set of electrical vehicles with the objective of minimum cost. The EVs participating in the emergency power supply process are selected based on the distance and throughput performance between the base station and the EVs
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Climate change is a well-known factor driving species range shifts. These shifts are often attributed to the relaxation of harsher climates at the northern range limit. Specifically, lack of cold tolerance as a constraint on range expansion at higher latitudes is one hypothesis. However, few, if any, studies have tested this hypothesis during a critical season: fall, when organisms are subjected to sporadic low temperature exposure but may not have become cold tolerant yet. In this study, I investigated the impact of low temperature on the larvae of the Giant swallowtail butterfly, Papilio cresphontes, at its northern range edge by integrating physiological experiments and species distribution modelling. First, the cold hardiness of the larvae was tested in a laboratory by determining their supercooling point, chill coma temperature and survival at three low temperatures. I found that the supercooling point was -6.6°C, that larvae use a freeze avoidant strategy, and that larvae enter a chill coma at 2.4°C. I also found that exposure to -2°C did not lead to a high rate of mortality, but that larval survival was impeded by temperatures below the SCP with temperatures below SCP (-8°C) produced high mortality (10-12% survival). Second, to determine the importance of low temperatures at a broad scale, I compared species distribution models of P. cresphontes based only on environmental data derived from other sources to models that also included the physiologically-derived parameters I generated experimentally. The modelling revealed that growing degree days and precipitation best predicted the distribution of P. cresphontes. The cold tolerance variables did not explain much variation in habitat suitability of P. cresphontes distribution. As such, the modelling results were consistent with the experimental results: low temperatures in the fall are unlikely to limit the distribution of P. cresphontes. Further investigation into the ecological relevance of the physiological thresholds determined here will improve our understanding of range expansion of P. cresphontes due to climate change. This study demonstrates that a combination of approaches provides a strong test of hypotheses related to the factors that limit species distributions.
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Typical Parkinson’s disease (PD) is thought to be caused by a combination of genetic and environmental factors. α-Synuclein (SNCA) is central to PD pathogenesis; however, functions of SNCA outside the brain remain largely unknown. We, and others, have found that wild-type Snca expression confers anti-microbial effects in mice by reducing the severity of viral infections. Our aim is to further characterize a role of SNCA in systemic and brain health of the host during infection. We hypothesize that SNCA plays a role in innate defenses and that SNCA gene dosage will modulate outcomes of infection in the brain following pathogen exposure. Intranasal delivery of reovirus in mouse pups causes systemic illness, leading to encephalitis. In this study, intracranial inoculations of reovirus are used to differentiate the relative contribution of Snca-mediated protection in the brain versus the periphery. Two outcomes are monitored: survival and viral titres in select organs. When comparing wild-type Snca, heterozygous, and knock-out mice, I found that Snca expression did not confer any protection with respect to survival or regarding viral brain titres. These results are paralleled by cellular overexpression models. Unexpectedly, the anti-viral property of Snca, which was previously observed systemically with three distinct dsRNA viruses, did not extend to a paradigm where neural cells were directly exposed to reovirus. These results suggest a complex, anti-viral role for Snca in host defenses that may be mediated, in part, outside the central nervous system. Future studies will address whether this occurs in peripheral neurons or cells of hematopoietic lineages.
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Jordan is among the poorest countries in the world with respect to water resources. Water scarcity in Jordan is an alarming problem that can jeopardize the economy and the stability of the country. It is a multidimensional problem caused by many factors such as the fluctuation of annual precipitation rates, the rapid change in population caused by the refugee influx from neighbouring countries, and the economic situation of the country. The water scarcity problem is aggravated by limitations in water management. This research investigated the shortcomings of water management that contribute to water scarcity. It involves a literature review, a survey questionnaire and interviews. These methods aim to assess the current challenges that prompt water scarcity, understand the water management shortcomings and their causes, identify the existing government solutions for water scarcity, and propose a sustainable solution for this problem. The research finds that water management in Jordan has several shortcomings such as the lack of monitoring and controlling water resources and preventing illegal drilling, the incapability of the government to reduce the non-revenue water as a result of aged water network and water theft, and illegal practices of the agricultural and industrial sectors. This research proposed a solution that aim to mitigate water scarcity in Jordan by enhancing several management practices. Moreover, the proposed solution calls for efficient managerial practices to be adopted by decision makers and the public. I argue that the proposed solutions are sustainable and cheaper than the existing government solutions that rely on searching for new water resources rather than improving water management.
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Reaching with altered visual feedback of the hand’s position in a virtual environment leads to reach adaptation in the trained hand, and also in the untrained hand (Wang & Sainburg, 2002). In the current study, we asked if reach adaptation in the untrained (right) hand is due to transfer of explicit (i.e., EA; conscious strategy) and/or implicit adaptation (i.e., IA; unconscious) from the left (trained) hand, and if the transfer of EA and IA changes depending on how one is made aware of the visuomotor distortion. We further asked if EA and IA are retained in the trained and untrained hand for 24 hours. Participants (n=60) were evenly divided into 3 groups (Strategy, No-Strategy, and Control). All participants reached to visual targets while seeing a cursor on the screen that was rotated 40° clockwise relative to their hand motion. Participants in the Strategy group were instructed on how to counteract the visuomotor distortion. The No-Strategy group was not told of the upcoming visuomotor distortion but was later asked to reach while engaging in any strategy they had learned in order to assess EA. Participants in the Control group were also not told of the upcoming visuomotor distortion and were never instructed to engage in any strategy when reaching. EA and IA were assessed in both the trained and untrained hands immediately following rotated reach training, and 24 hours later by having participants reach without the cursor when instructed to: (1) aim so that your hand lands on the target (to assess IA) and (2) use what was learned during training so that the cursor lands on the target (to assess EA + IA; exception of Control group). Results revealed that the groups differed with respect to the extent of reach adaptation achieved when initially training with the rotated cursor, such that the Strategy group had greater EA and less IA compared to the No-Strategy group in the trained hand. Unexpectedly, the Control group also showed less IA compared to the No-Strategy group, but was similar to the Strategy group. For both the Strategy and No-Strategy groups, EA was transferred between hands and was retained over time. While the extent of IA varied between groups in the trained (left) hand immediately following reach training trials, significant transfer of IA was not found in any of the three groups. Retention of IA was observed in the trained hand but decayed over testing days. Together, these results suggest that while initial EA and IA in the trained hand is dependent on how one is made aware of the visuomotor distortion, transfer and retention of visuomotor adaptation is driven almost exclusively by EA, regardless of instructions provided.
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Cette thèse présente, dans un premier temps, un survol de la théorie de l’autofiction telle qu’elle a été établie par son créateur, Serge Doubrovsky, et étoffée par ses successeurs. L’analyse se base sur trois caractéristiques particulières de la vision doubrovskienne, soit l’homonymie ternaire, l’écriture et le réel. Chacune de ces caractéristiques est développée selon les éléments pertinents à ma propre création, incluant les écritures autobiographique et consonantique, le rapport au lecteur et la dualité inhérente au réel. De plus, j’examine la possibilité d’utiliser le pronom tu au lieu du je habituel dans l’autofiction, faisant appel, entre autres, aux travaux d’Émile Benveniste. Dans un deuxième temps, mon récit autofictionnel, « Avant la tuerie », explore la vie de l’autrice/narratrice/personnage, Tina Charlebois, qui doit rédiger une thèse de maîtrise pendant qu’elle ressent le poids de l’âge qui la tourmente. Parallèlement, elle se remémore des moments banaux et plus significatifs de son enfance, comme la séparation de ses parents qui est, encore aujourd’hui, un autre fardeau qu’elle traîne comme un boulet. Enfin, en troisième partie, je propose une analyse de mon autofiction en misant sur sa concordance avec les théories présentées dans la première partie de cette thèse. Je valide la triade homonymique, l’utilisation du pronom tu, l’écriture propre à l’auteur d’autofiction, le lien avec le lecteur et la présence irrévocable de la fissure dans le genre autofictionnel. Il s’agit ici d’un travail soudé par le besoin de se dépasser, de se récrire, de se redonner envie de prendre la plume.
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Background: In February 2018, Canada’s National Advisory Committee on Immunization (NACI) began recommending maternal immunization with pertussis-containing vaccine (Tetanus-diphtheria-acellular pertussis [Tdap]) during every pregnancy as a strategy to prevent pertussis infection in young infants. As a baseline for future evaluation of the NACI policy, this thesis aimed to describe the characteristics of women who received Tdap immunization during pregnancy in the pre-policy time period and assess the relationship between maternal Tdap immunization with obstetrical and perinatal outcomes. Methods: We performed a population-based retrospective cohort study of all live births in Ontario, from April 2012 to March 2017 using multiple linked provincial health administrative databases. Tdap immunization during pregnancy was ascertained using Tdap-specific immunization fee codes. We used an extended Cox regression model with a time-dependent exposure variable to estimate adjusted hazards ratios (aHR) for preterm and very preterm birth. All other outcomes (gestational hypertension, chorioamnionitis, small-for-gestational-age birth, neonatal intensive care unit admissions >24 hours, composite outcome for neonatal morbidity) were assessed using log-binomial regression to generate adjusted risk ratios (aRR). All estimates were adjusted using inverse probability of treatment weights derived from propensity scores. Results: Of the 621,903 pregnancies ending in a live birth, 11,750 (1.9%) women received Tdap during pregnancy. The maternal Tdap vaccination rate increased by 8-fold across the study time period, from 4.6 per 1000 women in fiscal-year 2012 to 39.1 per 1000 women in fiscal-year 2016. Women who were nulliparous, residing in a higher-income neighbourhood, and receiving adequate or intensive prenatal care had the highest vaccination rates. There were no significant increased risks (aHR/aRR [95% CI]) for preterm birth (0.99 [0.87-1.12]), very preterm birth (1.03 [0.71-1.50]), or small-for-gestational-age birth (0.95 [0.90-1.02]) in Tdap-exposed infants. A significant reduction in risk for neonatal hospitalization and morbidity (measured by a composite outcome) was found among exposed infants; however, these associations were attenuated following sensitivity analyses. Among Tdap-vaccinated women, compared to unvaccinated women, there was no association with chorioamnionitis (0.95 [0.79-1.15]), but a 19% lower risk of gestational hypertension was observed (0.81 [0.74-0.90]). Conclusions: We did not detect any adverse obstetrical or perinatal outcomes following Tdap vaccination during pregnancy. These results complement existing evidence that maternal Tdap vaccination is not associated with adverse outcomes in either the mother or infant. On-going evaluation in Canada is needed as Tdap coverage among pregnant women increases in the coming years.
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