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  • Factors Affecting Axial and Lateral Load Transfer of Hollow Fibre-Reinforced Polymer Piles In Soft Clay

    Resource Type:
    Report
    Creator:
    Lowry, Kelly
    Abstract:
    The growing interest in the long-term performance of pile foundations and their ability to resist the negative effects of water exposure and aggressive soils has led to considering non-corrosive materials such as fibre-reinforced polymer (FRP). The most common applications are light-bearing structures in waterfront environments, while applications for larger structures have not been widely accepted in industry due to the lack of long-term records and design guidelines available. Previous research has primarily focused on the load transfer of concrete-filled FRP tubes—making it difficult to quantify the performance of FRP as a piling material on its own. In this study, a numerical model using the finite element method was developed to simulate small-scale load tests of hollow carbon-fibre reinforced polymer (CFRP) and glass-fibre reinforced polymer (GFRP) piles in soft clay. Verification of the model was attained using results from axial and lateral load tests on small-scale hollow CFRP and GFRP piles and pile-soil interaction was modelled using experimental data from interface shear tests conducted at Carleton University. A parametric analysis was performed to investigate and determine the key factors that influence the axial and lateral load response of hollow FRP piles. The findings of this research indicate that the number of FRP layers impacts loading behaviour significantly, while inner tube soil height has a reasonable influence on axial load response and fibre orientation has a minor effect under lateral load conditions.
    Date Created:
    2022-12-23

  • Ice Island and Iceberg Fluxes from Canadian High Arctic Sources

    Resource Type:
    Report
    Creator:
    Crawford, Anna, Copland, Luke, Mueller, Derek, and Van Wychen, Wesley
    Date Created:
    2023-02-22

  • The emerging technology collection at Carleton University Library: supporting experiential learning in the university curriculum

    Resource Type:
    Poster
    Creator:
    Cross, Emma
    Abstract:
    The emerging technology collection at Carleton University is a successful collaboration between the Library, Discovery Centre for Undergraduate Research & Engagement and Information Technology Services. Starting with a pilot project in Jan. 2015, the collection now provides access to over 40 pieces of technology equipment for loan. The poster will discuss benefits and challenges associated with this project and the value of shared Library space for the development and delivery of an innovative new service. Conference poster presented at the Ontario Library Association SuperConference on Friday February 3, 2017.
    Date Created:
    2017-02-03

  • Threshold Concepts for Teaching Information Literacy in the Classroom

    Resource Type:
    Poster
    Creator:
    Tudin, Susan
    Abstract:
    Poster presented at the Teaching & Learning Symposium, Carleton University, May 11, 2016
    Date Created:
    2016-05-11

  • Research can be fun!: Recruiting future students by showcasing Library resources at Carleton

    Resource Type:
    Poster
    Creator:
    Tudin, Susan and McLeod, Margaret
    Abstract:
    A 9 person team of library specialists taught 10 half-day mini sessions to 15 students during the week of May 3-7, 2010 and explored different areas of the MacOdrum Library’s collection that incorporated innovative, academic research techniques. Poster presented at the Canadian Library Association National Conference. Ottawa: May 30-June 2, 2012.
    Date Created:
    2015-05-30

  • Report on the State of Alternative Energy in the Arctic

    Resource Type:
    Report
    Creator:
    Keyte, Lawrence, Dufresne, Vincent, Mallett, Alexandra, Cherniak, David, and Schott, Stephan
    Abstract:
    This report provides a contemporary snapshot of domestic energy usage in Canada’s Arctic (spanning Yukon in the west to Nunatsiavut in the east) with a focus on how Northern jurisdictions meet their electricity and space heating needs. Specifically, the research team investigated the role of alternative energy options, including the governance, policies and financial analysis of these sectors. The team also examined the emerging field of energy conservation and efficiency measures, which have featured prominently in recent years. The report also examines eight case studies from across Canada’s Arctic regions, which represent a cross-section of northern alternative energy and energy efficiency technologies, including both public and privately-driven projects. Each case study includes a project description, objectives and drivers, the role of policy, and a description of barriers, outcomes, success factors and lessons learned. The case studies are divided into five operational case studies, describing projects already constructed and producing renewable heat or power, or reducing demand-side energy loss, and three forward-looking case studies, representing projects still under active development. The report concludes with suggested areas for research and policy recommendations regarding energy system planning, financial policy, and education, engagement and collaboration, in the Canadian Arctic context.
    Date Created:
    2015-09-21

  • Exhibits and Events at MacOdrum Library: A Practical Guide

    Resource Type:
    Other
    Creator:
    Draayer, Ingrid
    Abstract:
    This guide combines the knowledge gathered during my long career coordinating the Carleton University Library exhibits program and my recent sabbatical research on exhibits and events in academic libraries. Between 1983, when I was hired as Exhibits Librarian at Carleton University Library, and 2002, when the Library had little space available for exhibits and I became Head of Access Services, I was responsible for running the Library’s exhibits program. After the latest renovation to MacOdrum Library was completed in the Fall of 2013 and included dedicated space for exhibits, I was once again asked to coordinate and produce exhibits for the Library. During my 2014/2015 sabbatical I investigated the current state of exhibits and events in academic libraries through literature and Web searches and site visits to a number of universities. The end result is this guide, which I hope is both practical and inspirational.
    Date Created:
    2015-09-10

  • Branding History at the Canadian Museum of Civilization

    Resource Type:
    Article
    Creator:
    Aronczyk, Melissa and Brady, Miranda J.
    Abstract:
    In October 2012, the Canadian Heritage Minister announced that the Canadian Museum of Civilization, the country’s largest and most popular museum, would be renamed the Canadian Museum of History. In addition to the new name, three strategies—a strategy of engagement, a strategy of authority, and a strategy of expansion—were elaborated by museum and government officials as part of the transformation. We examine these three strategies as an example of the Harper government’s attempt to “brand” Canadian identity and history in its own image, arguing that the strategies were designed expressly to paper over near-unilateral changes in the museum’s mandate and transformation. Ultimately, these changes have problematic implications for the democratic management of cultural production in Canada.
    Date Created:
    2015-09-01

  • University Biology Patrons in the Library Literature 2000-2010: A Content Analysis & Literature Review

    Resource Type:
    Article
    Creator:
    Newton Miller, Laura
    Abstract:
    The researcher conducted a content analysis and literature review of papers written from 2000-2010 that focused on university biology students, faculty, and their papers. Scholarly articles were divided into the library research domains. The largest number of papers was from the Education domain, followed closely by Collections. Only two papers were categorized as Reference/Enquiries, and no papers were found in Management and Professional Issues. This research will enable science librarians to better understand what has already been written about biology subjects in a university setting. Gaps in the literature can help other librarians who are interested in pursuing more research with biology subjects.
    Date Created:
    2011-10-16

  • Labour Costs for Inventory Control Less Expensive than Repurchasing [Evidence Summary]

    Resource Type:
    Other
    Creator:
    Newton Miller, Laura
    Abstract:
    Review of article describing an inventory system that was created within the library and to show the cost-effectiveness of using the inventory system compared to the price of reacquiring mis-shelved books.
    Date Created:
    2010-10-16

  • NAT Traversal in Peer-to-Peer Architecture

    Resource Type:
    Report
    Creator:
    Daigle, Alexandre, Poulin, Marc-André, Maldague, Lucas Rioux, and Gagnon, François
    Abstract:
    Peer-to-peer networks are well known for file sharing between multiple computers. They establish virtual tunnels between computers to transfer data, but NATs makes it harder. A NAT, Network Address Translation, is a process which transforms private IP addresses, such as 192.168.2.1, into public addresses, such as 203.0.113.40. The idea is that multiple private addresses can hide behind a single public address and thus virtually enlarge the number of allocable public IP addresses. When an application in the local network establishes a connection to Internet, the packet passes through the NAT which adjusts the IP header and maps an external port to the computer which sent the request. When packets are received from the Internet by the NAT, they are forwarded to the internal host which is mapped to the port on which the packet was received, or dropped if no mapping exists. In this paper, we will introduce you to NAT and P2P, we will discuss the numerous ways NATs use to translate private IP addresses into public ones, we will discuss known techniques used to fix the problem and we will also present how popular peer-to-peer programs bypass NATs. This paper is written so anybody with a reasonable knowledge of networking would grasp the essentials. It is important to keep in mind that the traversal methods presented in this document work for UDP and TCP and require no manual configuration of the Network Address Translator itself.
    Date Created:
    2012-10-30

  • Entropy, triangulation, and point location in planar subdivisions

    Resource Type:
    Article
    Creator:
    Langerman, S., Morin, P., Dujmovic, V., Iacono, J., and Collette, S.
    Abstract:
    A data structure is presented for point location in connected planar subdivisions when the distribution of queries is known in advance. The data structure has an expected query time that is within a constant factor of optimal. More specifically, an algorithm is presented that preprocesses a connected planar subdivision, G, of size n and a query distribution, D, to produce a point location data structure for G. The expected number of point-line comparisons performed by this data structure, when the queries are distributed according to D, is H' + O(H^{1/2}+1) where H'=H'(G,D)$ is a lower bound on the expected number of point-line comparisons performed by any linear decision tree for point location in G under the query distribution D. The preprocessing algorithm runs in O(n log n) time and produces a data structure of size O(n). These results are obtained by creating a Steiner triangulation of G that has near-minimum entropy.
    Date Created:
    2013-02-25

  • The "Xochimilco model" for managing irregular settlements in conservation land in Mexico City

    Resource Type:
    Article
    Creator:
    Wigle, Jill
    Abstract:
    Mexico City has long been known as one of the world’s largest mega-cities. Although, the city’s growth rates have slowed since the 1980s, this process is not manifested evenly in spatial terms. Peripheral municipalities continue to grow at higher rates, including those municipalities in the southern part of the Federal District that contain its remaining conservation land. This growth is largely, but not exclusively, driven by the ongoing search for housing among lower-income households in the form of irregular settlement. Over time, this incremental pattern of settlement expansion has fragmented conservation land and impaired its ecological functioning. Given their role in land use planning with the reintroduction of elected local governments in the Federal District in 1997, this situation has placed municipalities quite literally at the ‘‘frontlines” of this planning and sustainability challenge. This paper examines the approach for managing land use regularization processes related to irregular settlement in conservation land adopted by the municipality of Xochimilco in its 2005 urban development plan, with reference to the experience of a specific case study community. Based on a series of interviews with residents and planning officials, the paper documents the highly-negotiated nature of ‘‘normative” planning that focuses on mitigating the impact of settlement in the conservation zone rather than stopping it completely. Given the enormous social pressures to access land for housing, the paper concludes that realistic efforts to preserve the remaining conservation land must involve a more comprehensive approach that better integrates environmental and social equity issues within and among municipal and upper-levels of government.
    Date Created:
    2010-04-17

  • Social Relations, Property and 'Peripheral' Informal Settlement: The Case of Ampliación San Marcos, Mexico City

    Resource Type:
    Article
    Creator:
    Wigle, Jill
    Abstract:
    This article explores the complexities of informal urbanisation at the metropolitan periphery of Mexico City through a case study of Ampliación San Marcos, a former agricultural area on the city's south-eastern periphery. While the physical annexation of small towns and their environs is a common feature of Mexico City's growth, the settlement of Ampliación San Marcos is more accurately described as a two-pronged process involving the extension of a nearby pre-Hispanic town and the expansion of Mexico City itself. The case study shows that the rural periphery of Mexico City is no tabula rasa upon which urban growth simply 'takes place', rather, settlement processes are influenced by longstanding in situ social relations and practices related to property. The paper highlights the importance of considering the relationships among social relations, property and informal settlement for understanding the complexity of metropolitan growth and change in large cities such as Mexico City.
    Date Created:
    2009-03-01

  • Information Management in the Canadian Federal Government: Principles, Practices and the Role of Information Professionals

    Resource Type:
    Report
    Creator:
    Stricker, Ulla de and Jordan, Isla
    Abstract:
    Information management (IM) in the Canadian public sector is a complex area involving many professions such as librarians, archivists, records managers and information technology professionals. This exploratory study looks at the literature and experiential (qualitative) evidence from IM professionals in order to paint a picture of information management principles and practice in the Canadian federal government. Personal interviews were conducted with 20 librarians, information managers, records managers and other information professionals. Responses indicated that although the public sector has made tremendous strides in IM, there is often a gap between IM policy and practice as shown by inconsistencies and confusion in day to day operations compounded by the decimation of federal libraries (which are repositories of external as well as government information). The study also looks at roles of librarians and other IM professionals now and in the future. These professionals are well positioned to help close the gap between information policy and practice, moving forward toward more coordinated and integrated practices in information management as well as making information accessible and usable for their clients. Such functions aid the Canadian public sector in becoming a more effective knowledge organization.
    Date Created:
    2013-04-02

  • Personal Learning Environments (PLEs): Ecologies for building student capability for lifelong learning

    Resource Type:
    Report
    Creator:
    Renon, Flavia
    Abstract:
    The purpose of this working paper is to examine the role of Personal Learning Environments (PLEs) in higher education. This information will serve as a framework to inform a study of PLE use at Carleton University.
    Date Created:
    2013-04-30

  • Self Portraits: The Cinemas of Canada since Telefilm.

    Resource Type:
    Book
    Creator:
    Loiselle, Andre and McSorley, Tom
    Date Created:
    2006-01-01

  • Quebecus Horribilis: Theatricality, the «Moment of Horror» and Quebec’s «Satanist» Cinema.

    Resource Type:
    Article
    Creator:
    Loiselle, Andre
    Abstract:
    In their book, Grand-Guignol: The French Theatre of Horror (2002), Richard J. Hand and Michael Wilson argue that horror plays performed at the Théâtre du Grand-Guignol from the late 19th century to the theatre’s closure in the early 1960s generally oscillated in style between realism and melodrama. The former would prevail during most of the drama, as the “normal” narrative would unfold, until the “moment of horror” when the tone would switch drastically to melodramatic dread. This article argues that a similar shift operates in Quebec horror films, especially those films that deal with Satanism. At “moments of horror,” these films replicate the theatricality of stylized melodrama, breaking with the realism of secure normality. The shift from realism to theatricality is all the more unsettling in French Canadian horror films that Quebec cinema has traditionally tended towards realism and has generally avoided the “fantastique”. This break from the realist tradition of Quebec cinema parallels the films’ break from French Canada’ religious tradition, as moments of horror coincide with moments of blasphemy. Looking at three Quebec “Satanist” films from the past thirty-five years (Le Diable est parmi nous, The Pyx, and Sur le seuil), the author identifies elements of montage and mise-en-scène that represent instances of cinematic theatricality, where the set, the cinematography, the editing, the actor’s gestures and speech, through theatrical artifice, stand out as aberrations within the realistic, Catholic milieu depicted on screen.
    Date Created:
    2008-03-20

  • Publishing Graduate Student Research in Geography: The Fundamentals

    Resource Type:
    Article
    Creator:
    Tudin, Susan and Ballamingie, Patricia
    Abstract:
    This paper offer practical advice on publishing graduate student research within the discipline of geography, addressing the following questions: why, when, where, what, how and with whom? Section 'The paper chase' delineates the importance of publishing, identifies potential material to publish, suggests venues in which to publish and offers pragmatic advice on how to negotiate the publishing process (with regards to peers, supervisors and editors). Section 'In library resources' discusses the effective use of library resources, demystifies the significance of impact factors and elucidates the history of Open Access publishing.
    Date Created:
    2013-09-18

  • Assessment Practice in Canadian University Libraries: Survey Results

    Resource Type:
    Report
    Creator:
    McKenna, Julie and Jordan, Isla
    Abstract:
    Accountability and data-informed decision-making are increasingly important for Canadian public institutions such as governments and universities. Canadian university libraries also appear to be placing more emphasis on evaluating and assessing their services and products. To discover more about the current assessment culture in Canadian university libraries, in 2007 Isla Jordan from Carleton University and Julie McKenna from the University of Regina conducted an online survey of services assessment practices in Canadian university libraries. The goals of this project were to gain a sense of assessment practices within the libraries and to provide a baseline for future comparisons and research into services assessment practice. Results showed that survey respondents were at different stages in assessing a variety of services and products. Respondents indicated that their libraries intended to increase their assessment activities in the future, particularly the LibQUAL survey.
    Date Created:
    2013-09-30

  • The Paradoxical Nature of the Canadian Identity

    Resource Type:
    Article
    Creator:
    Nimijean, Richard
    Date Created:
    2005-02-01

  • Athermal silicon waveguides with bridged subwavelength gratings for TE and TM polarizations

    Resource Type:
    Article
    Creator:
    Ibrahim, Marc, Janz, Siegfried, Cheben, Pavel, Xu, Dan-Xia, Schmid, Jens H., Ma, Rubin, Aleali, Alireza, Lamontagne, Boris, Bock, Przemek J., Lapointe, Jean, Densmore, Adam, and Ye, Winnie N.
    Abstract:
    In this paper, athermal silicon waveguides using bridged subwavelength grating (BSWG) structures are proposed and investigated. The realization of temperature-independent BSWG waveguides for both polarizations is demonstrated numerically and experimentally. SU-8 polymer is used as the cladding material to compensate for the positive thermo-optic (TO) coefficient (dn/dT) of silicon. We investigate the dependence of the effective TO coefficient of BSWG waveguides on both the bridge width and grating duty cycle. The BSWG waveguides have a width of 490 nm, a height of 260 nm, and a grating pitch of 250 nm. Athermal behavior is achieved for both the transverse-magnetic (TM) and the transverse-electric (TE) polarized light for a variety of bridge width and duty cycle combinations. Furthermore, the BSWGs can be designed to be athermal for both TE and TM polarization simultaneously.
    Date Created:
    2012-07-30

  • Explicit and implicit issues in the developmental cognitive neuroscience of social inequality

    Resource Type:
    Article
    Creator:
    D'Angiulli, Amedeo, Lipina, Sebastian J., and Olesinska, Alice
    Abstract:
    The appearance of developmental cognitive neuroscience (DCN) in the socioeconomic status (SES) research arena is hugely transformative, but challenging. We review challenges rooted in the implicit and explicit assumptions informing this newborn field. We provide balanced theoretical alternatives on how hypothesized psychological processes map onto the brain (e.g., problem of localization) and how experimental phenomena at multiple levels of analysis (e.g., behavior, cognition and the brain) could be related. We therefore examine unclear issues regarding the existing perspectives on poverty and their relationships with low SES, the evidence of low-SES adaptive functioning, historical precedents of the “alternate pathways” (neuroplasticity) interpretation of learning disabilities related to low-SES and the notion of deficit, issues of “normativity” and validity in findings of neurocognitive differences between children from different SES, and finally alternative interpretations of the complex relationship between IQ and SES. Particularly, we examine the extent to which the available laboratory results may be interpreted as showing that cognitive performance in low-SES children reflects cognitive and behavioral deficits as a result of growing up in specific environmental or cultural contexts, and how the experimental findings should be interpreted for the design of different types of interventions—particularly those related to educational practices—or translated to the public—especially the media. Although a cautionary tone permeates many studies, still, a potential deficit attribution—i.e., low-SES is associated with cognitive and behavioral developmental deficits—seems almost an inevitable implicit issue with ethical implications. Finally, we sketch the agenda for an ecological DCN, suggesting recommendations to advance the field, specifically, to minimize equivocal divulgation and maximize ethically responsible translation.
    Date Created:
    2015-08-21

  • Forging A Template for Undergraduate Collaborative Research: A Case Study

    Resource Type:
    Article
    Creator:
    Graham, Debra, Couchman, Ronald, and Hempstead, Janet
    Abstract:
    Undergraduate collaborative research is highlighted in many university initiatives; how-ever there is a lack of exemplars in disciplines that do not employ the scientific method. “Pop Music Reviews” was an attempt to forge a template for Women’s and Gender Stud-ies. This paper presents a description of the pilot project and provides qualitative assess-ments by the first- and second-year students, fourth-year teaching assistant (TA), refer-ence librarian, and professor. Together, the appraisals indicate that there are two different but equally necessary components for a successful collaborative research endeavour: the structural setting and the social and emotional environment. In both these components, there were weaknesses in the areas of planning and background training. Yet, the benefits as perceived through the experiences of the various participants were significant. Report-ed gains included increased understanding of research processes and applications, en-hanced critical thinking skills, expanded disciplinary knowledge, improved student moti-vation and confidence, greater interest in graduate studies, and the fostering of collegial interactions and mentoring.
    Date Created:
    2012-09-09

  • Vividness of visual imagery and incidental recall of verbal cues, when phenomenological availability

    Resource Type:
    Article
    Creator:
    Zakizadeh, Jila, Runge, Matthew, Faulkner, Andrew, D'Angiulli, Amedeo, Morcos, Selvana, and Chan, Aldrich
    Abstract:
    The relationship between vivid visual mental images and unexpected recall (incidental recall) was replicated, refined, and extended. In Experiment 1, participants were asked to generate mental images from imagery-evoking verbal cues (controlled on several verbal properties) and then, on a trial-by-trial basis, rate the vividness of their images; 30 min later, participants were surprised with a task requiring free recall of the cues. Higher vividness ratings predicted better incidental recall of the cues than individual differences (whose effect was modest). Distributional analysis of image latencies through ex-Gaussian modeling showed an inverse relation between vividness and latency. However, recall was unrelated to image latency. The follow-up Experiment 2 showed that the processes underlying trial-by-trial vividness ratings are unrelated to the Vividness of Visual Imagery Questionnaire (VVIQ), as further supported by a meta-analysis of a randomly selected sample of relevant literature. The present findings suggest that vividness may act as an index of availability of long-term sensory traces, playing a non-epiphenomenal role in facilitating the access of those memories.
    Date Created:
    2013-01-02

  • Adaptive Plasticity in Wild Field Cricket’s Acoustic Signaling

    Resource Type:
    Article
    Creator:
    Fitzsimmons, Lauren P., Harrison, Sarah J., Thomson, Ian R., and Bertram, Susan
    Abstract:
    Phenotypic plasticity can be adaptive when phenotypes are closely matched to changes in the environment. In crickets, rhythmic fluctuations in the biotic and abiotic environment regularly result in diel rhythms in density of sexually active individuals. Given that density strongly influences the intensity of sexual selection, we asked whether crickets exhibit plasticity in signaling behavior that aligns with these rhythmic fluctuations in the socio-sexual environment. We quantified the acoustic mate signaling behavior of wild-caught males of two cricket species, Gryllus veletis and G. pennsylvanicus. Crickets exhibited phenotypically plastic mate signaling behavior, with most males signaling more often and more attractively during the times of day when mating activity is highest in the wild. Most male G. pennsylvanicus chirped more often and louder, with shorter interpulse durations, pulse periods, chirp durations, and interchirp durations, and at slightly higher carrier frequencies during the time of the day that mating activity is highest in the wild. Similarly, most male G. veletis chirped more often, with more pulses per chirp, longer interpulse durations, pulse periods, and chirp durations, shorter interchirp durations, and at lower carrier frequencies during the time of peak mating activity in the wild. Among-male variation in signaling plasticity was high, with some males signaling in an apparently maladaptive manner. Body size explained some of the among-male variation in G. pennsylvanicus plasticity but not G. veletis plasticity. Overall, our findings suggest that crickets exhibit phenotypically plastic mate attraction signals that closely match the fluctuating socio-sexual context they experience.
    Date Created:
    2013-07-22

  • The social biology professor: Effective strategies for social media engagement

    Resource Type:
    Article
    Creator:
    Katti, Madhusudan and Bertram, Susan
    Abstract:
    Evolutionary biology and ecology have always been collaborative enterprises, benefitting enormously from active communication of ideas among traditional academic networks of peers. The Internet age, with its thriving online social networks, offers new tools that can help our current generation of biologists to collaborate, and communicate with the public, more effectively. Having a dynamic web presence, being part of an active blogging, Facebook, or Google+ community, and being a strategic tweeter can help your research, teaching, and service programs. Below we outline how to be a strategically savvy and active social media scientist, and discuss some of the pitfalls to avoid wasting time. We highlight some ecologists and evolutionary biologists who are active in social media to help you understand the many ways social media can help you in your academic life.
    Date Created:
    2013-07-07

  • Circannual changes in stress and feeding hormones and their effect on food-seeking behaviors.

    Resource Type:
    Article
    Creator:
    Holahan, Matthew, Cahill, Shaina, and Tuplin, Erin
    Abstract:
    Seasonal fluctuations in food availability show a tight association with seasonal variations in body weight and food intake. Seasonal variations in food intake, energy storage and expenditure appear to be a widespread phenomenon suggesting they may have evolved in anticipation for changing environmental demands. These cycles appear to be driven by changes in external daylength acting on neuroendocrine pathways. A number of neuroendocrine pathways, two of which are the endocrine mechanisms underlying feeding and stress, appear to show seasonal changes in both their circulating levels and reactivity. As such, variation in the level or reactivity to these hormones may be crucial factors in the control of seasonal variations in food-seeking behaviours. The present review examines the relationship between feeding behavior and seasonal changes in circulating hormones. We hypothesize that seasonal changes in circulating levels of glucocorticoids and the feeding-related hormones ghrelin and leptin contribute to seasonal fluctuations in feeding-related behaviors. This review will focus on the seasonal circulating levels of these hormones as well as sensitivity to these hormones in the modulation of food-seeking behaviors.
    Date Created:
    2013-07-23

  • Flavonol-rich dark cocoa significantly decreases plasma endothelin-1 and improves cognitive responses in urban children.

    Resource Type:
    Article
    Creator:
    D'Angiulli, Amedeo, Aragón-Flores, Mariana, Mukherjee, Partha S., Cross, Janet V., Gómez-Garza, Gilberto, Zhu, Hongtu, Chao, Chih-kai, Mora-Tiscareño, Antonieta, Franco-Lira, Maricela, Engle, Randall, Jewells, Valerie, Solorio, Edelmira, Weili, Lin, Medina-Cortina, Humberto, Torres-Jardón, Ricardo, Calderón-Garcidueñas, Lilian, and Ferreira-Azevedo, Lara
    Abstract:
    Air pollution exposures are linked to systemic inflammation, cardiovascular and respiratory morbidity and mortality, neuroinflammation and neuropathology in young urbanites. In particular, most Mexico City Metropolitan Area (MCMA) children exhibit subtle cognitive deficits, and neuropathology studies show 40% of them exhibiting frontal tau hyperphosphorylation and 51% amyloid-β diffuse plaques (compared to 0% in low pollution control children). We assessed whether a short cocoa intervention can be effective in decreasing plasma endothelin 1 (ET-1) and/or inflammatory mediators in MCMA children. Thirty gram of dark cocoa with 680 mg of total flavonols were given daily for 10.11 ± 3.4 days (range 9–24 days) to 18 children (10.55 years, SD = 1.45; 11F/7M). Key metabolite ratios in frontal white matter and in hippocampus pre and during cocoa intervention were quantified by magnetic resonance spectroscopy. ET-1 significantly decreased after cocoa treatment (p = 0.0002). Fifteen children (83%) showed a marginally significant individual improvement in one or both of the applied simple short memory tasks. Endothelial dysfunction is a key feature of exposure to particulate matter (PM) and decreased endothelin-1 bioavailability is likely useful for brain function in the context of air pollution. Our findings suggest that cocoa interventions may be critical for early implementation of neuroprotection of highly exposed urban children. Multi-domain nutraceutical interventions could limit the risk for endothelial dysfunction, cerebral hypoperfusion, neuroinflammation, cognitive deficits, structural volumetric detrimental brain effects, and the early development of the neuropathological hallmarks of Alzheimer's and Parkinson's diseases.
    Date Created:
    2013-08-02

  • Charting the role of the number line in mathematical development

    Resource Type:
    Article
    Creator:
    LeFevre, Jo-Anne, Kamawar, Deepthi, Jimenez Lira, Carolina, Sowinski, Carla, Cankaya, Ozlem, and Skwarchuk, Sheri-Lynn
    Abstract:
    Individuals who do well in mathematics and science also often have good spatial skills. However, the predictive direction of links between spatial abilities and mathematical learning has not been firmly established, especially for young children. In the present research, we addressed this issue using a sample from a longitudinal data set that spanned 4 years and which includes measures of mathematical performance and various cognitive skills, including spatial ability. Children were tested once in each of 4 years (Time 1, 2, 3, and 4). At Time 3 and 4, 101 children (in Grades 2, 3, or 4 at Time 3) completed mathematical measures including (a) a number line task (0–1000), (b) arithmetic, and (c) number system knowledge. Measures of spatial ability were collected at Time 1, 2, or 3. As expected, spatial ability was correlated with all of the mathematical measures at Time 3 and 4, and predicted growth in number line performance from Time 3 to Time 4. However, spatial ability did not predict growth in either arithmetic or in number system knowledge. Path analyses were used to test whether number line performance at Time 3 was predictive of arithmetic and number system knowledge at Time 4 or whether the reverse patterns were dominant. Contrary to the prediction that the number line is an important causal construct that facilitates learning arithmetic, no evidence was found that number line performance predicted growth in calculation more than calculation predicted number line growth. However, number system knowledge at Time 3 was predictive of number line performance at Time 4, independently of spatial ability. These results provide useful information about which aspects of growth in mathematical performance are (and are not) related to spatial ability and clarify the relations between number line performance and measures of arithmetic and number system knowledge.
    Date Created:
    2013-08-29

  • Covariation and repeatability of male mating effort and mating preferences in a promiscuous fish.

    Resource Type:
    Article
    Creator:
    Godin, Jean-Guy and Auld, Heather L.
    Abstract:
    Although mate choice by males does occur in nature, our understanding of its importance in driving evolutionary change remains limited compared with that for female mate choice. Recent theoretical models have shown that the evolution of male mate choice is more likely when individual variation in male mating effort and mating preferences exist and positively covary within populations. However, relatively little is known about the nature of such variation and its maintenance within natural populations. Here, using the Trinidadian guppy (Poecilia reticulata) as a model study system, we report that mating effort and mating preferences in males, based on female body length (a strong correlate of fecundity), positively covary and are significantly variable among subjects. Individual males are thus consistent, but not unanimous, in their mate choice. Both individual mating effort (including courtship effort) and mating preference were significantly repeatable. These novel findings support the assumptions and predictions of recent evolutionary models of male mate choice, and are consistent with the presence of additive genetic variation for male mate choice based on female size in our study population and thus with the opportunity for selection and further evolution of large female body size through male mate choice.
    Date Created:
    2013-10-03

  • Can convict cichlids (Amatitlania siquia) socially learn the degree of predation risk associated with novel visual cues in their environment?

    Resource Type:
    Article
    Creator:
    Barks, Patrick M. and Godin, Jean-Guy
    Abstract:
    For many animals, the ability to distinguish cues indicative of predation risk from cues unrelated to predation risk is not entirely innate, but rather is learned and improved with experience. Two pathways to such learning are possible. First, an animal could initially express antipredator behaviour toward a wide range of cues and subsequently learn which of those cues are non-threatening. Alternatively, it could initially express no antipredator behaviour toward a wide range of cues and subsequently learn which of them are threatening. While the learned recognition of threatening cues may occur either through personal interaction with a cue (asocial learning) or through observation of the behaviour of social companions toward a cue (social learning), the learned recognition of non-threatening cues seems to occur exclusively through habituation, a form of asocial learning. Here, we tested whether convict cichlid fish (Amatitlania siquia) can socially learn to recognize visual cues in their environment as either threatening or non-threatening. We exposed juvenile convict cichlids simultaneously to a novel visual cue and one of three (visual) social cues: a social cue indicative of non-risk (the sight of conspecifics that had previously been habituated to the novel cue), a social cue indicative of predation risk (the sight of conspecifics trained to fear the novel cue), or a control treatment with no social cue. The subsequent response of focal fish, when presented with the novel cue alone, was not influenced by the social cue that they had previously witnessed. We therefore did not find evidence that convict cichlids in our study could use social learning to recognize novel visual cues as either threatening or non-threatening. We consider alternative explanations for our findings.
    Date Created:
    2013-10-03

  • Neuroplasticity and the next wave of antidepressant strategies

    Resource Type:
    Article
    Creator:
    Hayley, Shawn and Litteljohn, Darcy
    Abstract:
    Depression is a common chronic psychiatric disorder that is also often co-morbid with numerous neurological and immune diseases. Accumulating evidence indicates that disturbances of neuroplasticity occur with depression, including reductions of hippocampal neurogenesis and cortical synaptogenesis. Improper trophic support stemming from stressor-induced reductions of growth factors, most notably brain derived neurotrophic factor (BDNF), likely drives such aberrant neuroplasticity. We posit that psychological and immune stressors can interact upon a vulnerable genetic background to promote depression by disturbing BDNF and neuroplastic processes. Furthermore, the chronic and commonly relapsing nature of depression is suggested to stem from “faulty wiring” of emotional circuits driven by neuroplastic aberrations. The present review considers depression in such terms and attempts to integrate the available evidence indicating that the efficacy of current and “next wave” antidepressant treatments, whether used alone or in combination, is at least partially tied to their ability to modulate neuroplasticity. We particularly focus on the N-methyl-D-aspartate (NMDA) antagonist, ketamine, which already has well documented rapid antidepressant effects, and the trophic cytokine, erythropoietin (EPO), which we propose as a potential adjunctive antidepressant agent.
    Date Created:
    2013-10-30

  • Two-mode division multiplexing in a silicon-on-insulator ring resonator

    Resource Type:
    Article
    Creator:
    Dorin, Bryce A. and Ye, Winnie N.
    Abstract:
    Mode-division multiplexing (MDM) is an emerging multiple-input multiple-output method, utilizing multimode waveguides to increase channel numbers. In the past, silicon-on-insulator (SOI) devices have been primarily focused on single-mode waveguides. We present the design and fabrication of a two-mode SOI ring resonator for MDM systems. By optimizing the device parameters, we have ensured that each mode is treated equally within the ring. Using adiabatic Bezier curves in the ring bends, our ring demonstrated a signal-to-crosstalk ratio above 18 dB for both modes at the through and drop ports. We conclude that the ring resonator has the potential for filtering and switching for MDM systems on SOI.
    Date Created:
    2014-02-13

  • Development of a Biocompatible Layer-by-Layer Film System using Aptamer Technology for Smart Material Applications

    Resource Type:
    Article
    Creator:
    DeRosa, Maria C. and Foster, Amanda
    Abstract:
    Aptamers are short, single-stranded nucleic acids that fold into well-defined three dimensional (3D) structures that allow for binding to a target molecule with affinities and specificities that can rival or in some cases exceed those of antibodies. The compatibility of aptamers with nanostructures such as thin films, in combination with their affinity, selectivity, and conformational changes upon target interaction, could set the foundation for the development of novel smart materials. In this study, the development of a biocompatible aptamer-polyelectrolyte film system was investigated using a layer-by-layer approach. Using fluorescence microscopy, we demonstrated the ability of the sulforhodamine B aptamer to bind its cognate target while sequestered in a chitosan-hyaluronan film matrix. Studies using Ultraviolet-visible (UV-Vis) spectrophotometry also suggest that deposition conditions such as rinsing time and volume play a strong role in the internal film interactions and growth mechanisms of chitosan-hyaluronan films. The continued study and development of aptamer-functionalized thin films provides endless new opportunities for novel smart materials and has the potential to revolutionize the field of controlled release.
    Date Created:
    2014-05-08

  • Non enim ab hiis que sensus est iudicare sensum. Sensation and Thought in Theaetetus, Plotinus and Proclus.

    Resource Type:
    Article
    Creator:
    MacIsaac, D. Gregory
    Abstract:
    I examine the relation between sensation and discursive thought (dianoia) in Plato, Plotinus, and Proclus. In Theaetetus, a soul whose highest faculty was sensation would have no unified experience of the sensible world, lacking universal ideas to give order to the sensible flux. It is implied that such universals are grasped by the soul’s thinking. In Plotinus the soul is not passive when it senses the world, but as the logos of all things it thinks the world through its own forms.Proclus argues against the derivation of universal logoi from the senses, which alone can’t make the sensible world comprehensible. At most they give a record of the original sense-impression in its particularity. The soul’s own projected logoi give the sensible world stability. For Proclus, bare sensation does not depend on thought, but a unified experience of the sense-world depends on its paradigmatic logoi in our souls.
    Date Created:
    2014-05-14

  • Level up! Designing a gaming lab at Carleton University Library

    Resource Type:
    Poster
    Creator:
    Smith, Robert and Cross, Emma
    Abstract:
    Poster presented by Emma Cross and Robert Smith at the Ontario Library Association Superconference 2014 in Toronto, Ontario.
    Date Created:
    2014-02-03

  • Power up! Building a games collection at an academic library

    Resource Type:
    Poster
    Creator:
    Cross, Emma and Smith, Robert
    Abstract:
    Poster presented at Canadian Library Association Conference 2012. Winner of best poster presentation.
    Date Created:
    2012-06-01

  • In the company of my peers: implementation of RDA in Canada

    Resource Type:
    Article
    Creator:
    Grover, Trina, Riva, Pat, Andrews, Sue, Cross, Emma, and Oliver, Chris
    Abstract:
    This article describes the progress made toward implementing Resource Description and Access (RDA) in libraries across Canada, as of Fall 2013. Differences in the training experiences in the English-speaking cataloging communities and French-speaking cataloging communities are discussed. Preliminary results of a survey of implementation in English-Canadian libraries are included as well as a summary of the support provided for French-Canadian libraries. Data analysis includes an examination of the rate of adoption in Canada by region and by sector. Challenges in RDA training delivery in a Canadian context are identified, as well as opportunities for improvement and expansion of RDA training in the future.
    Date Created:
    2014-01-10

  • Getting ready for RDA: a modular approach to training library staff

    Resource Type:
    Poster
    Creator:
    Cross, Emma
    Abstract:
    Resource Description and Access is the new content standard coming Spring 2013, with national libraries using RDA effective March 30, 2013. Libraries need to address training for staff in all departments on how to interpret, catalogue and use RDA records.
    Date Created:
    2013-02-13

  • Bachelor of Information Technology - Information Resource Management: a joint initiative between Carleton University and Algonquin College

    Resource Type:
    Poster
    Creator:
    Merriam, Helena and Cross, Emma
    Abstract:
    Carleton University and Algonquin College are collaborating on the development of a new joint degree program, the Bachelor of Information Technology - Information Resource Management (BIT-IRM). This unique 4 year program will enable students to graduate with both a Bachelor of Information Technology degree and a Library and Information Technician diploma. Poster presented at the Canadian Library Association Conference in 2014.
    Date Created:
    2014-06-02

  • Carleton University Library: Library Technician Internship Pilot Project

    Resource Type:
    Poster
    Creator:
    Cross, Emma
    Abstract:
    Overview of a project to establish an internship for library technicians at Carleton University Library. Poster presented at the Ontario Library Association Super Conference January 2012.
    Date Created:
    2012-01-31

  • Graduate students and copyright: informing graduate students about copyright issues in relation to their thesis

    Resource Type:
    Poster
    Creator:
    Cross, Emma
    Abstract:
    Poster presentation “Graduate students and copyright: informing graduate students about copyright issues in relation to their thesis” by Emma Cross given at the Canadian ETD and Open Repositories Workshop held May 10-11, 2010 at Carleton University. Poster describes a project to promote awareness of copyright issues amongst graduate students at Carleton University Library and the Faculty of Graduate Studies and Research.
    Date Created:
    2010-05-15

  • 70% and Climbing: E-Resources, Books, and Library Restructuring

    Resource Type:
    Article
    Creator:
    Sharp, David, Jones, Wayne, and Newton Miller, Laura
    Abstract:
    Within the past decade, academic libraries have seen a shift in purchasing from mostly print to mostly electronic. Although Carleton University Library (Ottawa, Canada) has experienced this shift, it had continued until recently to work within the confines of an organizational structure based on a print purchasing model. This paper will describe in detail the restructuring of the Library's collections and technical services departments to better meet growing electronic demands. Changes included dedicating more staff from print resources to e-resources, changing a librarian position to focus specifically on collections assessment, and shifting budgets to manage growing e-resources more efficiently. The authors will explore accomplishments and hurdles that needed to be overcome, cite lessons learned in making organizational shifts, and make some cautious predictions about future changes.
    Date Created:
    2014-07-03

  • “Lagging Behind” : An Examination of Why Women Continue to be So Underrepresented in Canadian Federal Politics

    Resource Type:
    Research Paper
    Creator:
    Pettie, Jasmin
    Abstract:
    The purpose of this study was to explore the question of why women are still so underrepresented in Canadian federal politics and specifically within the Canadian House of Commons despite advances in representation in many other fields. To answer this question a study was conducted using qualitative data obtained from interviews with 17 female Members of the 42nd Parliament of Canada between October 2018 to April 2019. Data collected through these interviews was analyzed qualitatively using a combination of content and discourse analysis to summarize, categorize, and investigate the verbal, written, and behavioural data that was obtained. Findings from this study mostly confirm the findings of previous research with a few key exceptions. New findings from this study include that a more nuanced relationship exists between female MP’s and the media than previously thought; that most of the women who run for office at the federal level have very little or no knowledge of the nomination, candidate, and electoral process before they start; and that a toxic work place culture exists within the House of Commons and this negatively impacts the experience that female MP’s have and is one of the reasons women are more likely to have shorter political terms and leave politics after shorter amounts of time when compared to their male counterparts.
    Date Created:
    2019-10-16

  • Flowering and fruiting responses to climate change of two Arctic plant species, purple saxifrage (Saxifraga oppositifolia) and mountain avens (Dryas integrifolia)

    Resource Type:
    Article
    Creator:
    Panchen, Zoe A. and Gorelick, Root
    Abstract:
    In temperate regions, there are clear indications that spring flowering plants are flowering earlier due to rising temperatures of contemporary climate change. Temperatures in temperate regions are rising predominantly in spring. However, Arctic regions are seeing unprecedented temperature increases, predominantly towards the end of the growing season. We might, therefore, expect to see earlier flowering of later-season flowering Arctic plants. Parks Canada has been monitoring purple saxifrage (Saxifraga oppositifolia) and mountain avens (Dryas integrifolia) flowering and fruiting times for 20 years at Tanquary Fiord, Qut- tinirpaaq National Park, Ellesmere Island. Saxifraga oppositifolia flowers in early spring, while D. integrifolia flowers in midsummer. Over the 20-year period, Tanquary Fiord’s annual and late-summer temperatures have risen significantly. During the same timeframe, D. integrifolia showed a trend towards earlier flowering and fruiting, but S. oppositifolia showed no changes in flowering or fruiting time. Flowering time was related to monthly temperatures just prior to flowering. The number of flowers produced was related to the previous autumn’s monthly temperatures. We found no relationship between flowering time and snowmelt date. Our findings suggest that Arctic community level ecological effects from climate change induced phenology changes will differ from those in temperate regions.
    Date Created:
    2016-05-17

  • On the Importance of Training Data Sample Selection in Random Forest Image Classification : A Case Study in Peatland Ecosystem Mapping

    Resource Type:
    Article
    Creator:
    Millard, Koreen and Richardson, Murray
    Abstract:
    Random Forest (RF) is a widely used algorithm for classification of remotely sensed data. Through a case study in peatland classification using LiDAR derivatives, we present an analysis of the effects of input data characteristics on RF classifications (including RF out-of-bag error, independent classification accuracy and class proportion error). Training data selection and specific input variables (i.e., image channels) have a large impact on the overall accuracy of the image classification. High-dimension datasets should be reduced so that only uncorrelated important variables are used in classifications. Despite the fact that RF is an ensemble approach, independent error assessments should be used to evaluate RF results, and iterative classifications are recommended to assess the stability of predicted classes. Results are also shown to be highly sensitive to the size of the training data set. In addition to being as large as possible, the training data sets used in RF classification should also be (a) randomly distributed or created in a manner that allows for the class proportions of the training data to be representative of actual class proportions in the landscape; and (b) should have minimal spatial autocorrelation to improve classification results and to mitigate inflated estimates of RF out-of-bag classification accuracy.
    Date Created:
    2016-05-17

  • Perceptions of the International Baccalaureate (IB) in Ontario Universities

    Resource Type:
    Article
    Creator:
    Fitzgerald, Saira
    Abstract:
    This article presents the results of the first phase of a research project on perceptions of the International Baccalaureate Diploma Program (IBDP) in Canadian universities. Establishing explicit university recognition policies for IBDP students has been an ongoing task for the International Baccalaureate Organization (IBO), which conducted two studies on university perceptions of the IBDP in the UK (2003) and Australia/New Zealand (2007). The present study replicates these studies in the Canadian context, to discover how admissions officers in Ontario universities perceive the IBDP in relation to other curricula. Preliminary results reveal a high degree of uniformity in responses, consistent with the previous studies. The IBO is indicated as being the primary source of information, suggesting that it plays an important part in forming perceptions of the IBDP.
    Date Created:
    2016-05-17

  • Major Alterations of Phosphatidylcholine and Lysophosphotidylcholine Lipids in the Substantia Nigra Using an Early Stage Model of Parkinson’s Disease

    Resource Type:
    Article
    Creator:
    Smith, Catherine A., Hayley, Shawn, Smith, Jeffrey, and Farmer, Kyle
    Abstract:
    Parkinson’s disease (PD) is a progressive neurodegenerative disease affecting the nigrostriatal pathway, where patients do not manifest motor symptoms until >50% of neurons are lost. Thus, it is of great importance to determine early neuronal changes that may contribute to disease progression. Recent attention has focused on lipids and their role in pro- and anti-apoptotic processes. However, information regarding the lipid alterations in animal models of PD is lacking. In this study, we utilized high performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) and novel HPLC solvent methodology to profile phosphatidylcholines and sphingolipids within the substantia nigra. The ipsilateral substantia nigra pars compacta was collected from rats 21 days after an infusion of 6-hydroxydopamine (6-OHDA), or vehicle into the anterior dorsal striatum. We identified 115 lipid species from their mass/charge ratio using the LMAPS Lipid MS Predict Database. Of these, 19 lipid species (from phosphatidylcholine and lysophosphotidylcholine lipid classes) were significantly altered by 6-OHDA, with most being down-regulated. The two lipid species that were up-regulated were LPC (16:0) and LPC (18:1), which are important for neuroinflammatory signalling. These findings provide a first step in the characterization of lipid changes in early stages of PD-like pathology and could provide novel targets for early interventions in PD.
    Date Created:
    2016-05-17

  • The relationship between nature connectedness and happiness : a meta-analysis

    Resource Type:
    Article
    Creator:
    Capaldi, Colin A., Dopko, Raelyne L., and Zelenski, John M.
    Abstract:
    Research suggests that contact with nature can be beneficial, for example leading to improvements in mood, cognition, and health. A distinct but related idea is the personality construct of subjective nature connectedness, a stable individual difference in cognitive, affective, and experiential connection with the natural environment. Subjective nature connectedness is a strong predictor of pro-environmental attitudes and behaviors that may also be positively associated with subjective well-being. This meta-analysis was conducted to examine the relationship between nature connectedness and happiness. Based on 30 samples (n = 8523), a fixed-effect meta-analysis found a small but significant effect size (r = 0.19). Those who are more connected to nature tended to experience more positive affect, vitality, and life satisfaction compared to those less connected to nature. Publication status, year, average age, and percentage of females in the sample were not significant moderators. Vitality had the strongest relationship with nature connectedness (r = 0.24), followed by positive affect (r = 0.22) and life satisfaction (r = 0.17). In terms of specific nature connectedness measures, associations were the strongest between happiness and inclusion of nature in self (r = 0.27), compared to nature relatedness (r = 0.18) and connectedness to nature (r = 0.18). This research highlights the importance of considering personality when examining the psychological benefits of nature. The results suggest that closer human-nature relationships do not have to come at the expense of happiness. Rather, this meta-analysis shows that being connected to nature and feeling happy are, in fact, connected.
    Date Created:
    2016-05-17

  • Anisotropic effective permittivity of an ultrathin gold coating on optical fiber in air, water and saline solutions

    Resource Type:
    Article
    Creator:
    Zhou, Wenjun, Barry, Seán T., Mandia, David J., and Albert, Jacques
    Abstract:
    The optical properties of an ultrathin discontinuous gold film in different dielectric surroundings are investigated experimentally by measuring the polarization-dependent wavelength shifts and amplitudes of the cladding mode resonances of a tilted fiber Bragg grating. The gold film was prepared by electron-beam evaporation and had an average thickness of 5.5 nm ( ± 1 nm). Scanning electron imaging was used to determine that the film is actually formed of individual particles with average lateral dimensions of 28 nm ( ± 8 nm). The complex refractive indices of the equivalent uniform film in air at a wavelength of 1570 nm were calculated from the measurements to be 4.84−i0.74 and 3.97−i0.85 for TM and TE polarizations respectively (compared to the value for bulk gold: 0.54-i10.9). Additionally, changes in the birefringence and dichroism of the films were measured as a function of the surrounding medium, in air, water and a saturated NaCl (salt) solution. These results show that the film has stronger dielectric behavior for TM light than for TE, a trend that increases with increasing surrounding index. Finally, the experimental results are compared to predictions from two widely used effective medium approximations, the generalized Maxwell-Garnett and Bruggeman theories for gold particles in a surrounding matrix. It is found that both of these methods fail to predict the observed behavior for the film considered.
    Date Created:
    2015-05-21

  • “The Nothingness of Fame, At Least to Woman”: Felicia Hemans and the Price of Celebrity

    Resource Type:
    Article
    Creator:
    Grammatikos, Alex
    Date Created:
    2015-05-21

  • Mean Annual Precipitation Explains Spatiotemporal Patterns of Cenozoic Mammal Beta Diversity and Latitudinal Diversity Gradients in North America

    Resource Type:
    Article
    Creator:
    Gorelick, Root, Hassal, Christopher, Fraser, Danielle, and Rybczynski, Natalia
    Abstract:
    Spatial diversity patterns are thought to be driven by climate-mediated processes. However, temporal patterns of community composition remain poorly studied. We provide two complementary analyses of North American mammal diversity, using (i) a paleontological dataset (2077 localities with 2493 taxon occurrences) spanning 21 discrete subdivisions of the Cenozoic based on North American Land Mammal Ages (36 Ma – present), and (ii) climate space model predictions for 744 extant mammals under eight scenarios of future climate change. Spatial variation in fossil mammal community structure (b diversity) is highest at intermediate values of continental mean annual precipitation (MAP) estimated from paleosols (,450 mm/year) and declines under both wetter and drier conditions, reflecting diversity patterns of modern mammals. Latitudinal gradients in community change (latitudinal turnover gradients, aka LTGs) increase in strength through the Cenozoic, but also show a cyclical pattern that is significantly explained by MAP. In general, LTGs are weakest when continental MAP is highest, similar to modern tropical ecosystems in which latitudinal diversity gradients are weak or undetectable. Projections under modeled climate change show no substantial change in b diversity or LTG strength for North American mammals. Our results suggest that similar climate-mediated mechanisms might drive spatial and temporal patterns of community composition in both fossil and extant mammals. We also provide empirical evidence that the ecological processes on which climate space models are based are insufficient for accurately forecasting long-term mammalian response to anthropogenic climate change and inclusion of historical parameters may be essential.
    Date Created:
    2015-05-21

  • On the number of channels required for interference-free wireless mesh networks

    Resource Type:
    Article
    Creator:
    Chaudhry, Aizaz, Hafez, Roshdy HM, and Chinneck, John W
    Abstract:
    We study the problem of achieving maximum network throughput with fairness among the flows at the nodes in a wireless mesh network, given their location and the number of their half-duplex radio interfaces. Our goal is to find the minimum number of non-overlapping frequency channels required to achieve interference-free communication. We use our existing Select x for less than x topology control algorithm (TCA) to build the connectivity graph (CG), which enhances spatial channel reuse to help minimize the number of channels required. We show that the TCA-based CG approach requires fewer channels than the classical approach of building the CG based on the maximum power. We use multi-path routing to achieve the maximum network throughput and show that it provides better network throughput than the classical minimum power-based shortest path routing. We also develop an effective heuristic method to determine the minimum number of channels required for interference-free channel assignment.
    Date Created:
    2015-05-21

  • Democratization in Serbia: An Analysis of Rational Choice and Structuralist Explanations

    Resource Type:
    Article
    Creator:
    Apostolov-Dimitrijevic, Dunja
    Abstract:
    This paper explains political democratization in Post-Milosevic Serbia utilizing two different accounts of the democratization process: one rooted in the rational choice framework and the other in structuralism. While rational choice explains the decisive role of political leadership in overcoming path dependence, the structuralist explanations show the transnational linkages that encourage democratization in the face of domestic setbacks. This particular debate between the two types of explanations represents the larger debate concerning the role of internal factors and external linkages in propelling democratization in transitional societies. The paper concludes by integrating the two sets of explanations offered by each theoretical perspective, in order to develop a coherent understanding of Serbia's democratization.
    Date Created:
    2015-05-21

  • The impact of multiple memory formation on dendritic complexity in the hippocampus and anterior cingulate cortex assessed at recent and remote time points.

    Resource Type:
    Article
    Creator:
    Wartman, Brianne C. and Holahan, Mathew R.
    Abstract:
    Consolidation processes, involving synaptic and systems level changes, are suggested to stabilize memories once they are formed. At the synaptic level, dendritic structural changes are associated with long-term memory storage. At the systems level, memory storage dynamics between the hippocampus and anterior cingulate cortex (ACC) may be influenced by the number of sequentially encoded memories. The present experiment utilized Golgi-Cox staining and neuron reconstruction to examine recent and remote structural changes in the hippocampus and ACC following training on three different behavioral procedures. Rats were trained on one hippocampal-dependent task only (a water maze task), two hippocampal-dependent tasks (a water maze task followed by a radial arm maze task), or one hippocampal-dependent and one non-hippocampal-dependent task (a water maze task followed by an operant conditioning task). Rats were euthanized recently or remotely. Brains underwent Golgi-Cox processing and neurons were reconstructed using Neurolucida software (MicroBrightField, Williston, VT, USA). Rats trained on two hippocampal-dependent tasks displayed increased dendritic complexity compared to control rats, in neurons examined in both the ACC and hippocampus at recent and remote time points. Importantly, this behavioral group showed consistent, significant structural differences in the ACC compared to the control group at the recent time point. These findings suggest that taxing the demand placed upon the hippocampus, by training rats on two hippocampal-dependent tasks, engages synaptic and systems consolidation processes in the ACC at an accelerated rate for recent and remote storage of spatial memories.
    Date Created:
    2014-04-21

  • Robust silicon waveguide polarization rotator with an amorphous silicon overlayer

    Resource Type:
    Article
    Creator:
    Schmid, Jens H., Ye, Winnie N., Xiong, Yule, Xu, Dan-Xia, Cheben, Pavel, and Janz, Siegfried
    Abstract:
    We propose a robust polarization rotator based on the mode-evolution mechanism. The polarization rotation in a silicon wire waveguide is achieved by forming an amorphous silicon (a-Si) overlayer and an SiO_2 spacer on top of the waveguide. A strip pattern of a constant width is designed to be etched through the overlayer at a specific angle with respectto the Si waveguide. The asymmetry in the a-Si overlayer affects the waveguide mode by rotating the modal axis. This polarization rotator design is amenable to comparatively simple fabrication compatible with standard silicon photonic processing for integration. The length ofthe rotation section is 17 µm, and the broadband operation is achieved with a rotation efficiency higher than 90% for a wavelength range exceeding 135 nm. A maximum polarization rotation efficiency of 99.5% is predicted by calculation.
    Date Created:
    2014-02-19

  • Inquiry-based training improves teaching effectiveness of biology teaching assistants

    Resource Type:
    Article
    Creator:
    Ellefson, Michelle R. and Hughes, William
    Abstract:
    Graduate teaching assistants (GTAs) are used extensively as undergraduate science lab instructors at universities, yet they often have having minimal instructional training and little is known about effective training methods. This blind randomized control trial study assessed the impact of two training regimens on GTA teaching effectiveness. GTAs teaching undergraduate biology labs (n = 52) completed five hours of training in either inquiry-based learning pedagogy or general instructional "best practices". GTA teaching effectiveness was evaluated using: (1) a nine-factor student evaluation of educational quality; (2) a six-factor questionnaire for student learning; and (3) course grades. Ratings from both GTAs and undergraduates indicated that indicated that the inquiry-based learning pedagogy training has a positive effect on GTA teaching effectiveness.
    Date Created:
    2013-11-11

  • Interruption of Ghrelin Signaling in the PVN Increases High-Fat Diet Intake and Body Weight in Stressed & Non-Stressed C57BL6J Male Mice

    Resource Type:
    Article
    Creator:
    Isaacs, Albert M., Abizaid, Alfonso, Patterson, Zachary R., and Parno, Tamara
    Abstract:
    Chronic social stress has been associated with increased caloric intake and adiposity. These effects have been linked to stress induced changes in the secretion of ghrelin, a hormone that targets a number of brain regions to increase food intake and energy expenditure and promote increased body fat content. One of the brain sites targeted by ghrelin is the hypothalamic paraventricular nucleus (PVN), a region critical for both the regulation of the stress response and the regulation of energy balance. Given these data, we examined the contribution of ghrelin receptors in the PVN to the metabolic and behavioral changes that are seen during chronic social stress in mice. To do this, mice were implanted with cannulae attached to osmotic minipumps and delivering either vehicle or the ghrelin receptor (growth hormone secretagogue receptor) antagonist [D-Lys-3]-GHRP-6 (20 nmol/day/mouse). Following a week of recovery, half of the animals in each group were exposed to chronic social defeat stress for a period of 3 weeks whereas the other half were left undisturbed. During this time, all animals were given ad libitum access to standard laboratory chow and presented a high-fat diet for 4 h during the day. Results showed that the ghrelin receptor antagonism did not decrease stressed induced caloric intake, but paradoxically increased the intake of the high fat diet. This would suggest that ghrelin acts on the PVN to promote the intake of carbohydrate rich diets while decreasing fat intake and blockade of ghrelin receptors in the PVN leads to more consumption of foods that are high in fat.
    Date Created:
    2013-09-17

  • Understanding the neuroinflammatory response following concussion to develop treatment strategies

    Resource Type:
    Article
    Creator:
    Patterson, Zachary R. and Holahan, Mathew R.
    Abstract:
    Mild traumatic brain injuries (mTBI) have been associated with long-term cognitive deficits relating to trauma-induced neurodegeneration. These long-term deficits include impaired memory and attention, changes in executive function, emotional instability, and sensorimotor deficits. Furthermore, individuals with concussions show a high co-morbidity with a host of psychiatric illnesses (e.g., depression, anxiety, addiction) and dementia. The neurological damage seen in mTBI patients is the result of the impact forces and mechanical injury, followed by a delayed neuroimmune response that can last hours, days, and even months after the injury. As part of the neuroimmune response, a cascade of pro- and anti-inflammatory cytokines are released and can be detected at the site of injury as well as subcortical, and often contralateral, regions. It has been suggested that the delayed neuroinflammatory response to concussions is more damaging then the initial impact itself. However, evidence exists for favorable consequences of cytokine production following traumatic brain injuries as well. In some cases, treatments that reduce the inflammatory response will also hinder the brain's intrinsic repair mechanisms. At present, there is no evidence-based pharmacological treatment for concussions in humans. The ability to treat concussions with drug therapy requires an in-depth understanding of the pathophysiological and neuroinflammatory changes that accompany concussive injuries. The use of neurotrophic factors [e.g., nerve growth factor (NGF)] and anti-inflammatory agents as an adjunct for the management of post-concussion symptomology will be explored in this review.
    Date Created:
    2012-12-12

  • Calling, Courtship, and Condition in the Fall Field Cricket, Gryllus pennsylvanicus

    Resource Type:
    Article
    Creator:
    Harrison, Sarah J., Thomson, Ian R., Bertram, Susan M., and Grant, Caitlin M.
    Abstract:
    Theoretically, sexual signals should provide honest information about mating benefits and many sexually reproducing species use honest signals when signalling to potential mates. Male crickets produce two types of acoustic mating signals: a long-distance mate attraction call and a short-range courtship call. We tested whether wild-caught fall field cricket (Gryllus pennsylvanicus) males in high condition (high residual mass or large body size) produce higher effort calls (in support of the honest signalling hypothesis). We also tested an alternative hypothesis, whether low condition males produce higher effort calls (in support of the terminal investment hypothesis). Several components of long-distance mate attraction calls honestly reflected male body size, with larger males producing louder mate attraction calls at lower carrier frequencies. Long distance mate attraction chirp rate dishonestly signalled body size, with small males producing faster chirp rates. Shortrange courtship calls dishonestly reflected male residual mass, as chirp rate and pulse rate were best explained by a curvilinear function of residual mass. By producing long-distance mate attraction calls and courtship calls with similar or higher effort compared to high condition males, low condition males (low residual mass or small body size) may increase their effort in current reproductive success at the expense of their future reproductive success, suggesting that not all sexual signals are honest.
    Date Created:
    2013-03-20

  • Frontal EEG/ERP correlates of attentional processes, cortisol and motivational states in adolescents from lower and higher socioeconomic status

    Resource Type:
    Article
    Creator:
    Van Roon, Patricia Maria, Oberlander, Tim F., Grunau, Ruth E., Hertzman, Clyde, D’Angiulli, Amedeo, Weinberg, Joanne, and Maggi, Stefania
    Abstract:
    Event-related potentials (ERPs) and other electroencephalographic (EEG) evidence show that frontal brain areas of higher and lower socioeconomic status (SES) children are recruited differently during selective attention tasks. We assessed whether multiple variables related to self-regulation (perceived mental effort) emotional states (e.g., anxiety, stress, etc.) and motivational states (e.g., boredom, engagement, etc.) may co-occur or interact with frontal attentional processing probed in two matched-samples of fourteen lower-SES and higher-SES adolescents. ERP and EEG activation were measured during a task probing selective attention to sequences of tones. Pre- and post-task salivary cortisol and self-reported emotional states were also measured. At similar behavioural performance level, the higher-SES group showed a greater ERP differentiation between attended (relevant) and unattended (irrelevant) tones than the lower-SES group. EEG power analysis revealed a cross-over interaction, specifically, lower-SES adolescents showed significantly higher theta power when ignoring rather than attending to tones, whereas, higher-SES adolescents showed the opposite pattern. Significant theta asymmetry differences were also found at midfrontal electrodes indicating left hypo-activity in lower-SES adolescents. The attended vs. unattended difference in right midfrontal theta increased with individual SES rank, and (independently from SES) with lower cortisol task reactivity and higher boredom. Results suggest lower-SES children used additional compensatory resources to monitor/control response inhibition to distracters, perceiving also more mental effort, as compared to higher-SES counterparts. Nevertheless, stress, boredom and other task-related perceived states were unrelated to SES. Ruling out presumed confounds, this study confirms the midfrontal mechanisms responsible for the SES effects on selective attention reported previously and here reflect genuine cognitive differences.
    Date Created:
    2012-11-19

  • The rights and freedoms gradient of health: evidence from a cross-national study

    Resource Type:
    Article
    Creator:
    Bezo, Brent, Roberts, William L., and Maggi, Stefania
    Abstract:
    This study examined the combined influences of national levels of socioeconomic status (SES), social capital, and rights and freedoms on population level physical and mental health outcomes. Indicators of mental health were suicide rates, alcohol consumption, and tobacco use. Indicators of physical health included life expectancy, infant mortality rates, and prevalence of HIV. Using pathway analysis on international data from a selected sample of European, North American, South American, and South Caucasus countries, similar models for mental health and physical health were developed. In the first model, the positive effects of SES and social capital on physical health were completely mediated via rights and freedoms. In the second model, the positive effect of SES on mental health was completely mediated, while the impact of social capital was partially mediated through rights and freedoms. We named the models, the "rights and freedoms gradient of health" in recognition of this latter construct's crucial role in determining both physical and mental health.
    Date Created:
    2012-11-07

  • Student Research

    Digital Collection
    Description:
    A collection of outstanding papers and journal articles written by Carleton University students. Many of these papers were supported, in part, by the Carleton University Research Impact Endeavour (CURIE) Fund. For information about the CURIE Fund and Carleton's support for open access and scholarly publishing, see  https://library.carleton.ca/services/scholarly-communications/curie-fund
    0Collections
    20Works

  • Test Procedure for Conducted Energy Weapons, Version 3.0

    Resource Type:
    Report
    Creator:
    Dawson, David, Adler, Andy, and Sinclair, Ian
    Description:
    This paper is provided on the terms "As Is, Where Is", and the Authors give no warranty or representation of any kind whatsoever as to the appropriate policies for the use of, nor the safety of the use of CEWs. The Authors expressly disclaim all express or implied warranties relating to the contents of the paper. The Authors give no warranty or representation of any kind whatsoever that the recommendations contained in this report are comprehensive. The Authors give no warranty or representation of any kind whatsoever that the recommendations are up to date beyond the date on which the paper is published.
    Abstract:
    Several studies including the Braidwood Commission report, the Report of the Standing Committee on Public Safety and National Security of the Conducted Energy Weapon, the report of the Commission for Public Complaints against the RCMP and other provincial reports and coroners’ recommendations have discussed the need for reliable uniform testing of Conducted Energy Weapons (CEWs) independent of the manufacturer. This version (3.0) adds an appendix which describes testing of the Taser 7 CEW. The CEW Test Procedure: - Establishes a methodology by which testing facilities and personnel across Canada will be able to test CEWs and determine whether they are operating within manufacturers’ specifications; - Defines data collection requirements so that data collected during the testing of any CEW in Canada may be used in forensic analysis of that weapon and may also be added to a central data base for future research and data mining programs.
    Date Created:
    2021-02-17

  • Test Procedure for Conducted Energy Weapons, Version 1.1

    Resource Type:
    Report
    Creator:
    Dawson, David, Sinclair, Ian, Miller, Mark, Evans, Ron, Garland, Laurin, and Adler, Andy
    Abstract:
    Several studies have discussed the need for reliable uniform testing of Conducted Energy Weapons (CEWs) independent of the manufacturer. We propose a test proceedure that will enable organizations across Canada to test CEWs in a reliable, repeatable manner. This proceedure includes, but goes beyond, the one proposed by the manufacturer. Test results so obtained will also enable: 1. acceptance and regular validation of function of weapons in inventories of police service; 2. post incident testing to determine whether the weapon was functioning normally; 3. collection of weapons data across Canada to allow research on trends with age of weapon or other factors related to performance. The authors represent a group of subject matter experts who have been involved in research on or testing of CEWs.
    Date Created:
    2010-07-31

  • Test Procedure for Conducted Energy Weapons, Version 2.0

    Resource Type:
    Report
    Creator:
    Sinclair, Ian, Adler, Andy, and Dawson, David
    Abstract:
    Several studies have discussed the need for reliable uniform testing of Conducted Energy Weapons (CEWs) independent of the manufacturer. This Test Procedure is designed to enable organizations across Canada to test CEWs in a reliable, repeatable manner to determine whether they are operating within manufacturerʼs specifications. The CEW Test Procedure establishes a methodology by which testing facilities and personnel will be able to test CEWs and determine whether they are operating within manufacturers' specifications, and defines data collection requirements so that data collected may be used in forensic analysis and for future research.
    Date Created:
    2017-02-17

  • Procedure Recommendations for Conducted Energy Weapons

    Digital Collection
    0Collections
    3Works

  • Three Early Works - Response a M. de Malestroit, 1568

    Resource Type:
    Other
    Creator:
    McRae, Kenneth D., McCann, Alastair D., and Andreadis, Catherine
    Date Created:
    2011-01-14

  • République / De Republica, 1576

    Resource Type:
    Other
    Creator:
    Andreadis, Catherine, McCann, Alastair D., and McRae, Kenneth D.
    Date Created:
    2011-01-14

  • Three Early Works - Oratio ad senatum populumque tolosatem, 1559

    Resource Type:
    Other
    Creator:
    McRae, Kenneth D., McCann, Alastair D., and Andreadis, Catherine
    Date Created:
    2011-01-14

  • Three Early Works - Bodin's Commentary on Oppian, De venatione, 1555

    Resource Type:
    Other
    Creator:
    McRae, Kenneth D., McCann, Alastair D., and Andreadis, Catherine
    Date Created:
    2011-01-14

  • Methodus ad facilem historiarum cognitionem, 1572

    Resource Type:
    Other
    Creator:
    McCann, Alastair D., Andreadis, Catherine, and McRae, Kenneth D.
    Date Created:
    2011-01-14

  • General Introduction & Notes on Files Released to Date

    Resource Type:
    Other
    Creator:
    McCann, Alastair D., Andreadis, Catherine, and McRae, Kenneth D.
    Date Created:
    2011-01-14

  • De la démonomanie des sorciers, 1587

    Resource Type:
    Other
    Creator:
    McRae, Kenneth D., Andreadis, Catherine, and McCann, Alastair D.
    Date Created:
    2011-01-14

  • Bodin Sources Index

    Digital Collection
    Description:
    The Bodin Sources Index was established to list and explore all the sources cited in Bodin’s major works. Its scope includes both traditional print sources and also special categories alphabetized separately for non-traditional sources such as manuscripts, letters, oral sources, personal experiences, etc. The first of these files contains a General Introduction to the Bodin Sources Index, together with a brief note on each of the individual works released to date. This file is followed by separate data files, in tabular format, for each of these works. Symbols used in the data files are explained more fully on page 4 of the General Introduction. When cited, the project should be referred to as Bodin Sources Index, with the names of the three authors. With acknowledgment, the content may be used freely for scholarly purposes.
    0Collections
    7Works

  • Trends in the functions and organization of departmental personnel administration.

    Resource Type:
    Thesis
    Creator:
    Dowdell, Robert Hartley
    Thesis Degree:
    Master of Arts (M.A.)
    Thesis Degree Discipline:
    Public Administration
    Date Created:
    1964

  • The use of EEG and VR in Mental State Recognition

    Resource Type:
    Thesis
    Creator:
    El-Habrouk, Jaser
    Abstract:
    Mental state recognition (MSR) is important to multiple health-related fields. A virtual reality (VR) headset is used to induce mental states through both distractors and stressors. Participants solved arithmetic questions in VR, then outside of VR using a Muse S EEG device. A heart monitor was used throughout. Three research contributions followed: First, heart rate variability (HRV) data were compared between VR and non-VR sessions and correlated with established Test of Variables of Attention (T.O.V.A.) measurements used to asses participants' attention and focus. Second, a classifier was developed to differentiate between clean and noisy EEG data, with 92% accuracy. Lastly, linear regression models were developed, achieving mean squared error scores of 0.65 and 0.63 for 3-level stress and attention prediction from EEG data, respectively. In summary, this thesis explores the use of VR to induce mental states and advances the state of the art in EEG-based MSR.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Biomedical
    Date Created:
    2023

  • Anisotropy and Non-coaxial Behaviour of Sand Along Different Strain Paths

    Resource Type:
    Thesis
    Creator:
    Selvarajah, Premnath
    Abstract:
    Anisotropic characteristics of granular soil, consolidated to various initial stress states, were evaluated under generalized strain paths using hollow cylinder torsional shear tests. Fraser River sand samples prepared by water pluviation were subjected to isotropic and anisotropic consolidation stresses and sheared under undrained con- ditions along specific strain paths characterized by constant intermediate principal strain parameter (𝑏𝜀) and various fixed principal strain directions (𝛼𝜀). A series of tests along different inclinations of the major principal strain with respect to the vertical depositional direction permitted an assessment of the interaction between principal strain directions and fabric. A decrease in strain hardening tendency is ob- served as the major principal strain aligned towards the bedding plane. Considering different levels of anisotropic consolidation stresses also allowed a detailed examina- tion of how initial static shear affects the responses. In particular, generated principal stresses and their direction, as well as the pore pressure responses, were closely exam- ined. Novel findings, that highlight range of intermediate principal stress parameter (𝑏𝜎) associated with the undrained plane strain condition, and the interaction be- tween 𝑏𝜎 and 𝑏𝜀 during shearing are presented. It was found that 𝑏𝜎 systematically decreases with shear strain in constant 𝑏𝜀 tests. The 𝑏𝜎 value in plane strain tests (𝑏𝜀=0.5) was found to be in the range of 0.2 to 0.4 depending on the loading path, and the stage of shearing. The relationship between principal stress directions and plastic-strain increment directions was assessed to identify the nature of plasticity in the material. In order to ensure confident assessment of non-coaxiality, total strain was decomposed into elas- tic and plastic strain. The existence of non-coaxiality in Fraser River sand (FRS) was observed when the sand was subjected to undrained shear at fixed principal strain di- rections that do not coincide with the fabric axis of symmetry. Non-coaxiality was not observed when the principal directions of stress/strain coincided with the fabric axis of symmetry. It was also noticed that irrespective of the initial condition, the degree of non-coaxiality reduces with increasing shear strain. The influence of initial fabric and principal strain direction on the degree of non-coaxiality was analyzed in detail. Test results show that irrespective of initial condition, the degree of non-coaxiality reduces as the principal strain direction aligns towards the bedding plane direction. The degree of non-coaxiality in FRS at the phase transformation (PT) state and the effect of intermediate principal stress on non-coaxiality were also examined. Different values of degree of non-coaxiality at PT state indicate that the phase transformation state can not be thought of as a good representation of the critical state even though the friction angle at phase transformation has been found to be similar to that at the critical state. The results revealed that the non-coaxial behaviour of soil is also influenced by the intermediate principal stress parameter (which could alternatively be represented by the Lode angle). The influence of non-coaxiality on stress-dilatancy of sand was investigated under generalized loading conditions, and it was found that the effect of non-coaxiality on stress-dilatancy characteristics of the sand was influenced by its initial fabric anisotropy. The effect of non-coaxiality in stress-dilatancy relationship has been investigated within the theoretical framework developed by Gutierrez and Ishihara (Gutierrez and Ishihara, 2000, Soils Found., 40(2):49–59) and Gutierrez and Wang (Gutierrez and Wang, 2009, Granul. Matter, 11(2):129–137) who extended the Rowe’s stress-dilatancy relation to the non-coaxial conditions. Our research study verifies this framework beyond its original context of 2D simple shear tests.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Engineering, Civil
    Date Created:
    2023

  • Differential Introgression Between the Northern and Southern Extents of the Lodgepole x Jack Pine Hybrid Zone Suggests Environmentally-driven Selection and Local Adaptation.

    Resource Type:
    Thesis
    Creator:
    Yaremchuk, Danya Daria
    Abstract:
    Lodgepole and jack pine form a mosaic hybrid zone in western Canada. Introgression occurs between lodgepole and jack pine through this hybrid zone by repeated backcrossing with advanced generation hybrid progeny. Using environmentally-associated SNPs identified by redundancy analyses, we examined patterns of introgression between the northern and southern extents of this hybrid zone to identify differential introgression. Through genomic cline analyses, we found extensive introgression of these SNPs through the hybrid zone. Twenty-eight SNPs had significantly different patterns of introgression between the northern and southern extents. Fine-scale patterns revealed several SNPs that were introgressing more frequently than expected, suggesting adaptive introgression. We found that adaptive introgression is occurring more frequently in the northern hybrid extent compared to the southern hybrid extent, suggesting different environmental pressures. Using gene annotations and major allele frequency maps, we identified evidence of differing environmental pressures resulting in putative local adaptation within this hybrid zone.
    Thesis Degree:
    Master of Science (M.Sc.)
    Thesis Degree Discipline:
    Biology
    Date Created:
    2023

  • Toward a "Just, Peaceful and Safe Society:" How Risk Factors and Criminogenic Needs Align with Parole Decisions

    Resource Type:
    Thesis
    Creator:
    Mularczyk, Kimberly Patrycia
    Abstract:
    Board members (BMs), as gatekeepers between continued imprisonment and freedom, decide upon the potential release of incarcerated individuals considered for parole in Canada. Although a focal concern of BMs is community protection, annual Canadian government reports do not contain information on parole populations' criminogenic needs. Literature provides little insight into what factors might relate to parole decisions. In addition, prior research has not compared the risk profiles and release decisions of those who applied for day parole (DP) or full parole (FP) exclusively to those who applied simultaneously. The current dissertation addresses these gaps in two studies using an archival sample of federally sentenced individuals (N = 3,613). The sample includes conditional release and detention decisions made by the Parole Board of Canada between 2010 and 2017 (age at decision: M = 39 years old, SD = 12.80). Study 1 showed that risk/need scores and some institutional (e.g., CSC recommendation) and parole factors (e.g., decision type) predicted conditional release. CSC recommendations predicted release probability for DP (Adjusted Odds Ratio [AOR] = 35.33), FP (AOR = 18.83), and SR (men at a detention review; AOR = 43.94). Moreover, Study 1 found that among those who reoffended on FP (10-32% at one and two-year fixed follow-up) or men who reoffended on statutory release after a detention review (44-80%; at one and two-year fixed follow-up), most revocations (72-75%) first occurred for breaches as opposed to new crimes. Study 2 showed that BMs often imposed special conditions concerning alcohol, avoiding certain persons, drugs, reporting and disclosures, and treatment. Study 2 also found that after accounting for risk/need, the number of special conditions imposed on FP did not predict revocations for any breaches or crimes on FP at one-year (AOR = 1.11) or two-year (AOR = 0.82) fixed follow-up. Future research is required to untangle the potential overlapping variance that unmeasured variables (e.g., prior conditional release successes or revocations) may share with CSC recommendations. Overall, findings support the assertion that BMs use risk/need information to inform decisions and that the number of special conditions imposed does not influence revocation rates after accounting for risk/need.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Psychology
    Date Created:
    2023

  • Role of TrkB.T1 in Glial Inflammatory Response Elicited by MHV

    Resource Type:
    Thesis
    Creator:
    Heiratifar, Noora Donna
    Abstract:
    In the present thesis, we used a rodent analogous coronavirus, murine hepatitis virus (MHV), in culture to directly assess its impact on astrocytic and microglial cells. Given the increasing importance of the brain neurotrophic factor (BDNF)-TrkB signaling system in glial functioning, we also assessed whether the unique TrkB.T1 truncated isoform (the only BDNF receptor on astrocytes) would modulate glial reactivity to MHV viral infection. Our results largely support the notion that MHV readily infects astrocytes and caused a degree of toxicity of these cells. The addition of microglia to the astrocytic culture modulated the magnitude of this effect and greatly increased pro-inflammatory cytokine release. Furthermore, TrkB.T1 deficiency appeared to greatly reduce astrocyte viability and microglial morphology. These data may have useful implications for better understanding the nature of glial responses to coronaviral infection and the importance of TrkB in such responses.
    Thesis Degree:
    Master of Science (M.Sc.)
    Thesis Degree Discipline:
    Neuroscience
    Date Created:
    2023

  • Towards a critique of state secrecy: Uncovering the rhetorical practices of secret keepers and their legitimization by the discourse of law

    Resource Type:
    Thesis
    Creator:
    Lefebvre, Stephane
    Abstract:
    This thesis examines the rhetorical devices that secret keepers in Canada, the United Kingdom and the United States use to justify the non-disclosure of state secrets. It also examines the manner in which judges in these three countries write and speak about state secrets. By embracing the rhetorical devices used by secret keepers and materializing them in reported decisions, judges add legitimacy to the discourse of secret keepers and directly assist in its reproduction and distribution. Taken together, the discourse of the state and the discourse of law on state secrecy sets up the dominant interpretive frames with which any public engagement, whether supportive or critical, must engage. While the persuasive social effect and perceived legitimacy of this combined discourse may ebb and flow, it appears enduring and difficult to challenge despite the existence of counter-discourses and concessions such as the adoption of access to information legislation. This thesis seeks to understand how state secrecy discourse becomes or appears preeminent, and how it reproduces itself, as a first step in formulating a fuller critique of this discourse.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Legal Studies
    Date Created:
    2023

  • Modular Verification of Hierarchical Component-Based Software Systems

    Resource Type:
    Thesis
    Creator:
    Baak, James Alec William
    Abstract:
    Using Component-based Software Engineering approaches with Formal Methods has seen an influx of interest in the recent decades. The joining of these two disciplines have been stifled though due to unclear component specifications and expensive formal verification techniques, which hurt the reusability and scalability of complex software systems. In this work, we expand on current component-port-connector metamodels for formally specifying a system's architectural and behavioural requirements into a hierarchical component system structure by using abstract Composite Components. The Composite Components of a system model can then utilize modular verification for isolating the verification process into modules surrounding Composite Components and generating higher level properties. We formalize our metamodel in Alloy 6 and present a template for specifying system properties for modular verification which enables the reuse of previous verification efforts on satisfied modules. We conclude with an example case study system and analysis of the modular verification strategy.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Electrical and Computer
    Date Created:
    2023

  • Analysis of Open-Source Data in Wind Power Prediction Modeling

    Resource Type:
    Thesis
    Creator:
    von Zuben, Elizabeth Lynn
    Abstract:
    As identified in the 2021 IPCC AR6 WGIII report, wind energy has a high potential to reduce greenhouse gas emissions. The deployment of wind energy, however, has fallen behind its potential in part because of the need for improved wind power predictions. This thesis combines historical power production data, meteorological station data, reanalysis data, and numerical weather prediction output data (WRF model) to determine the optimal combination of data sources and variables for wind power prediction using a random forests model. A study then further evaluates reanalysis data and methods of bias correction for this type of data, to improve power predictions at 52 wind farms across Canada using power curve and machine learning methods. Recommendations are proposed for: the use of data sources and important input variables; the utility of global reanalysis data sources by terrain features; and the utility of bias correction methods for downstream wind power prediction.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Mechanical
    Date Created:
    2022

  • A NUMERICAL STUDY OF THE IMPACT OF MAKE-UP AIR VELOCITY ON THE SMOKE CONDITIONS IN AN ATRIUM

    Resource Type:
    Thesis
    Creator:
    Boakyewah, Barbara
    Abstract:
    This research numerically investigates the effect of make-up air on the smoke conditions in an atrium under different make-up air velocities and fire sizes. A total of twenty-four (24) simulations were conducted using the Fire Dynamics Simulator (FDS) to consider different scenarios of fire located at the center (axisymmetric), northwest corner and southeast corner of the atrium. Fire sizes of 1 MW, 3 MW and 5 MW along with different make-up air velocities of 1 m/s, 1.5 m/s, 2.5 m/s and 3.5 m/s were simulated to investigate their effect on smoke conditions the atrium. The results showed that the simulation predicted slightly higher temperatures and lower smoke layer heights when compared to the experimental tests. The position of the fire source at different locations showed different and increasing temperatures when the velocity changes from 1 m/s to 3.5 m/s, however the effects of make-up air velocities were minor.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Civil
    Date Created:
    2023

  • A Web Based Architecture to Operationalize Geospatial Simulation Environments

    Resource Type:
    Thesis
    Creator:
    St-Aubin, Bruno
    Abstract:
    Simulation is inherently multi-disciplinary. It requires knowledge about the system under study, expertise in simulation theory to define models and programming skills to implement models. Geospatial simulation requires an additional layer of expertise in topology, geospatial data structures, spatial analysis, computational geometry, and other related topics. Commercial modeling and simulation software can be used to provide an environment to facilitate simulation studies for users. However, these software tend to be narrowly scoped to specific business applications and tightly couple model and simulator. As such, it is difficult to expand their usage and reuse them outside of the application domain they were intended for. The Discrete Event System Specification (DEVS) is a modular and hierarchical simulation formalism that clearly separates the model, simulator and experiments. It can be used break down the disciplinary silos within which single-use simulators are built and allow users to study real-world systems from a broad range of application domains. In this research, we present an architecture that facilitates the operationalization of DEVS based, geospatial simulation environments in multidisciplinary projects. The architecture relies on a clear definition of roles and responsibilities to leverage the different skillsets in an organization. It considers a series of business processes for modelers, subject matter experts, web developers and end users. It relies on a web-based architecture to provide simulation as a service capability and support users across the entire simulation lifecycle. It seeks to democratize DEVS simulation by making use of the strengths and skills available in larger organizations and by providing the necessary tools for collaboration. Importantly, it preserves key features of DEVS (genericity, modularity, flexibility, etc.) and encourages users to follow best practices in model documentation to foster model reusability and improve model discoverability. It relies on modeling and simulation as a service to overcome technological barriers of entry for DEVS simulation and provide a set of reusable tools to design simulation-based, web applications for end users.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Engineering, Electrical and Computer
    Date Created:
    2023

  • QoS Performance Measurement Through SRv6 Network Programming for Smart City IoT Traffic

    Resource Type:
    Thesis
    Creator:
    Kuri, Sajib Kumar
    Abstract:
    Segment Routing over IPv6, also known as SRv6, is a modern networking solution that aims to improve the current Internet of Things (IoT) network's reliability, availability, and scalability. Performance measures are required to evaluate SRv6 behaviors or functions. The proposed work aims to provide real IoT traffic profiles to assess the performance of SRv6 behaviors. In particular, a three-module SRv6 programming model is proposed to measure the performance of SRv6 policy headend and endpoint behavior and ensure reliability and quality of service (QoS). Moreover, a novel finder algorithm for maximum receive rate (MRR) benchmarking is proposed, which can outperform existing techniques in terms of throughput/bandwidth performance while maintaining the same computational resources. Finally, implementation results provide insights into forwarding different IoT use-cases traffic based on the functional service requirements. That also ensures a higher usage level of existing IoT networks, minimizing the need for additional capacity and lowering network costs.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Electrical and Computer
    Date Created:
    2022

  • Constrained Geometric Optimization Problems

    Resource Type:
    Thesis
    Creator:
    D'Angelo, Anthony Mark
    Abstract:
    In this thesis we consider constrained geometric optimization problems. The first is a constrained version of the k-Steiner tree problem restricting the Steiner points to lie on a restricted set of curves. We solve the 1-Steiner tree problem in the Euclidean plane in optimal asymptotic time and space bounds when the Steiner point is constrained to lie on an input line. We then show how existing results can be used to generalize the result. The second problem is the smallest k-enclosing disc problem for a point set S contained in a simple polygon. In this problem we work with geodesic discs, meaning we use the geodesic distance function (i.e., the length of the shortest path). We present both a 2-approximation algorithm and an algorithm that finds the optimal radius for the smallest k-enclosing geodesic disc of a set of points inside a simple polygon. The last problem we consider is the smallest k-enclosing geodesic disc problem for a set of points in a simple polygon when the computed disc must be centred on an input chord of the polygon.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Computer Science
    Date Created:
    2023

  • Assessing the Beclin-1 Knockout: Autophagy, Neurogenesis, and the TUNL Task

    Resource Type:
    Thesis
    Creator:
    Bornheimer, Jacob
    Abstract:
    Autophagy is the intracellular process of isolating, enveloping, and recycling cell matter. Beclin-1 is a protein that acts as a lynchpin in the autophagic process. Animals lacking Beclin-1 are embryonically lethal, and knockout of Beclin-1 causes a reduction in adult hippocampal neurogenesis. The dentate gyrus (DG) is normally home to ongoing neurogenesis, which is thought to mediate pattern separation and memory encoding. First, I test a new protocol for the TUNL task. To assess whether a behavioural phenotype of Beclin-1 nKO is apparent, on the second experiment I compare TUNL performance between WT and KO mice. The new protocol for the TUNL task produces a reliable measure of pattern separation. Beclin-1 nKO reduced DG neurogenesis by 40% compared to WT. No difference between the WT and KO mice in TUNL task performance (pattern separation ability) was found but KO mice had lower activity in the CA1 during the task.
    Thesis Degree:
    Master of Science (M.Sc.)
    Thesis Degree Discipline:
    Neuroscience
    Date Created:
    2023

  • Optimal Selection of IPsec-Based Security Mechanisms in Resource Constrained IoT Environment

    Resource Type:
    Thesis
    Creator:
    Mahmoud, Abdullah Fahmi Mustafa
    Abstract:
    Internet of Things (IoT) is a modern-day technology that supports many different applications such as smart cities, e-health, and smart homes. However, the specific IoT nature of connecting various heterogeneous devices complicates the implementation of conventional security mechanisms. In this work, a device-based security approach has been proposed to assign optimal security mechanisms to the set of heterogeneous IoT devices based on their available resources and the system requirements. To achieve the proposed approach, the security overhead equation was formulated to include 3 parameters: RAM usage, energy consumption and throughput. A hardware implementation was used to measure these parameters and to calculate the security overhead for the tested security mechanisms. The Pareto frontline was used to select the optimal security mechanism that minimizes the security overhead per device while maximizing the system requirement. The selection algorithm was tested in a simulation of 50 heterogeneous devices that ran 30 security mechanisms.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Electrical and Computer
    Date Created:
    2023

  • MAWT: Multi-Attention-Weight Transformers

    Resource Type:
    Thesis
    Creator:
    Askin, Enver Deniz
    Abstract:
    Transformers are machine learning models designed to learn and predict sequential and structured data, which are crucial to tasks such as neural machine translation and semantic parsing. They have become state-of-the-art engines for both of these tasks and much research in natural language processing is devoted to increasing their performance by introducing modifications to their architectures. In light of this trend, this thesis introduces a new Transformer architecture called MAWT: Multi-Attention-Weight Transformers in an attempt to increase the accuracy and variety of the acceptable predictions of a Transformer. It attempts to achieve this by training multiple weights per each Transformer attention head, which then are used to test the accuracy of the engine. This creates a new architecture under which the system produces a candidate set of outputs (instead of a singly output), along with a method for selecting from the candidate set. My proposal rests on the assumption -- motivated by statistical considerations -- that having a candidate set increases the probability of finding an exact match within the set. Upon testing, I observed that my system outperforms the regular transformer on 5/6 benchmark neural machine translation and semantic parsing datasets, where engine performance is measured by exact match accuracy. Exact match accuracy demands syntactic identity between the output and the target. In order to investigate how well my new architecture generalizes to measures of semantic equivalence that don't also demand syntactic identity, I also recorded the BLEU scores on these datasets. The BLEU score is a measure of performance based on n-grams rather than exact symbolic match (i.e., how many contiguous sequence of n-many strings from the predicted output match the desired output). The results I report on the BLEU scores are more mixed, raising important questions that I highlight about the role of syntax in measures of semantic equivalence.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Cognitive Science
    Date Created:
    2023

  • Trimethylation Enhancement using Diazomethane (TrEnDi) Enhances Mass Spectrometry-Based Analysis of Glufosinate and 3-(Methylphosphinico)propionic Acid in Complex Matrices

    Resource Type:
    Thesis
    Creator:
    Sheedy, Krysten Lynn
    Abstract:
    Glufosinate is the second most commonly used herbicide worldwide; it inhibits glutamine synthetase, which results in increased ammonia levels in plants and mammals. Due to their high polarity, low volatility, small size and lack of chromophores and fluorophores, glufosinate and its breakdown product 3-(methylphosphinico) propionic acid (3-MPPA) are difficult to detect at trace levels. Using the chemical derivatization strategy trimethylation enhancement using diazomethane (TrEnDi), glufosinate and 3-MPPA react with diazomethane and tetrafluoroboric acid to become permethylated, thus reducing their polarity and forming a fixed permanent positive charge on the amine group of glufosinate. When using reversed-phase high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS), analyte retention and sensitivity are increased after derivatization, 6.7-fold for glufosinate and 6.3-fold for 3-MPPA. TrEnDi methodology was applied to canola samples from two separate fields sprayed with Liberty®. Prior to derivatization, the analysis showed no signal associated with unmodified glufosinate or 3- MPPA; however, TrEnDi modification resulted in quantifiable signals for both permethylated species.
    Thesis Degree:
    Master of Science (M.Sc.)
    Thesis Degree Discipline:
    Chemistry
    Date Created:
    2023

  • Evaluation of Remotely Piloted Aircraft Systems (RPAS)-based Structure-fromMotion (SfM) photogrammetry for characterizing microtopography and vegetation structure in a southeastern Ontario peatland

    Resource Type:
    Thesis
    Creator:
    Bernyk, Kimberly Ellen
    Abstract:
    Remotely piloted aircraft systems are a remote sensing platform for peatland researchers to monitor changes in vegetation height/composition/structure. In this work, an RPAS was flown to collect aerial images over Alfred Bog, a domed peatland complex located in Eastern Ontario. The images were processed with a photogrammetry technique called Structure-from-Motion, which can be used to create 3D point clouds of an x by y transect. The point cloud results were used to assess the utility of extracting ground terrain and vegetation height as compared to a transect field survey. This field survey was completed with a Trimble Catalyst RTK GNSS to record ground elevation and maximum vegetation height of the canopy top. The results from this research suggest that terrain information could not be extracted at all from the generated point clouds. Although, a digital surface model can be generated to model the canopy top and crown area.
    Thesis Degree:
    Master of Science (M.Sc.)
    Thesis Degree Discipline:
    Geography
    Date Created:
    2023

  • Histone Arginine Methylation in the Freeze-tolerant Wood Frog, Rana sylvatica

    Resource Type:
    Thesis
    Creator:
    Naranjo Vera, Mairelys
    Abstract:
    The wood frog, Rana sylvatica, is well known for its freeze tolerance ability. To endure winter, frozen frogs switch to a hypometabolic state via transcriptional regulation. Histone methylation is known to play a crucial role in regulating gene transcription. However, histone arginine methylation or demethylation has not previously been studied in the context of freeze tolerance. This thesis presents the first characterization of arginine methylation in a freeze tolerant vertebrate. Overall, levels of protein arginine methyltransferases (PRMTs) and methylated histone residues showed differential regulation over the freeze/thaw-cycle in wood frog liver. All PRMTs and downstream targets showed no changes during freezing, but protein levels of targets associated with transcription activation were elevated during thaw in skeletal muscle. Differential levels of histone demethylases were found in both tissues among the experimental conditions. These results indicate a role for histone methylation in supporting metabolic rate depression and tissue homeostasis during freezing.
    Thesis Degree:
    Master of Science (M.Sc.)
    Thesis Degree Discipline:
    Biology
    Date Created:
    2022

  • Simulating 3D Tailings Dam Breach With Thixotropic Bifurcation Rheology using the Material Point Method

    Resource Type:
    Thesis
    Creator:
    Xia, Xuexin
    Abstract:
    Mining is a booming industry and it indirectly involves everyone living in modern society. Tailings, the primary solid waste generated as the side effect of extracting valuable minerals, often require vast facilities to store the large quantity of waste. Failure of tailings storage facilities often causes significant damage both environmentally and economically, and frequently results in fatalities. Nowadays numerical simulation of tailings flows resulting from potential failures has become widespread in practice to assist the design of tailings storage facilities. In this thesis, tailings runout simulations are attempted using a numerical method suitable for large deformation analysis (Material Points Method) employing an advanced rheological model. This study aims to simulate the runout of tailings dam breach incident such as Merriespruit in South Africa using realistic geotechnical properties and producing results that fulfill the expectations from both geo-mechanical and hydrodynamical requirements.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Environmental
    Date Created:
    2023

  • When a Pandemic Meets an Epidemic: How COVID-19 has Affected Treatment Access Among Individuals with Problematic Opioid Use

    Resource Type:
    Thesis
    Creator:
    Polakova, Laura
    Abstract:
    The study examined the impact of the COVID-19 pandemic on treatment access among individuals (n=225) presenting with problematic opioid use to the Rapid Access Addiction Medicine (RAAM) clinic at The Royal in Ottawa, Ontario. The COVID-19 pandemic led to government-imposed restrictions and service limitations. The RAAM clinic underwent two primary changes: (1) delivering services virtually rather than in-person appointments and (2) shifting from walk-in services to appointment-based services. The study was a retrospective chart review and data were extracted from an electronic health record, Meditech. Participants were patients who had an initial presentation to the RAAM clinic between March 16th, 2019, and March 15th, 2021, and had used opioids within the 30 days prior to their visit. Results indicated that RAAM changes decreased some groups' access to care such that fewer patients experiencing precarious housing and mental health comorbidities presented to the RAAM clinic after the onset of the pandemic.
    Thesis Degree:
    Master of Arts (M.A.)
    Thesis Degree Discipline:
    Psychology
    Date Created:
    2023

  • Petrogenesis of Mafic-Ultramafic Intrusions in the Southern Goiás Magmatic Arc, Central Brazil

    Resource Type:
    Thesis
    Creator:
    Augustin, Claudia Tharis
    Abstract:
    The Americano do Brasil and Mangabal Complexes belong to a cluster of Neoproterozoic mafic-ultramafic intrusions in the southern Goiás Magmatic Arc in Brazil that lies within the Brasília Belt, a complex, long-lived Neoproterozoic Orogen that formed during the amalgamation of the São Francisco/Congo, Amazonian, and Paranapanema Cratons in western Gondwana. Although deformed and partially recrystallized by a regional metamorphic overprint, the rocks of both complexes still preserve igneous textures. The rocks in both complexes show cumulate textures that range from adcumulate to orthocumulate. Petrography, geochemistry, geochronology, and petrological modeling were carried out to constrain the petrogenesis of the complexes. Modeling indicates that the parental magma for the Americano do Brasil Complex had an OIB-like Fe-rich picrite composition, while the parental magma of the Mangabal Complex could have been a tholeiitic basalt. Considering the temporal and spatial correlations, decompression melting of upwelling asthenosphere triggered by rollback subduction and/or influence of a mantle plume are plausible mechanisms to explain the petrogenesis of these mafic-ultramafic intrusions in the vicinities of the eastern Arenópolis arc and westernmost Anápolis-Itauçu belt. The complexes have experienced a protracted metamorphic evolution with peaks indicating amphibolite facies. The rock from both complexes shows late-stage alteration associated with metasomatism by CO2-Ca-S-rich fluids.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Earth Sciences
    Date Created:
    2022

  • Safety Evaluation of Red-Light Cameras and Dynamic Speed Display Signs Within the City of Ottawa

    Resource Type:
    Thesis
    Creator:
    Saffarzadeh Parizi, Sorousha
    Abstract:
    This thesis evaluates the safety impacts of red-light cameras (RLCs) and Dynamic Speed Display Signs (DSDSs) in Ottawa, Canada. The study examines the safety impacts of RLCs on safety performance, using collision records, and driver behaviour using surrogate safety measures. The safety impacts of DSDSs on driver behaviour are evaluated using speed analysis. An empirical Bayes method for RLCs showed a significant impact, where total and PDO collisions increased while injury and fatal collisions decreased. The impact of RLCs also depended on the collision types, where sideswipe, rear-end, and SMV collisions increased, but the angle and turning collisions decreased. The increase in rear-end collisions was also examined through an analysis of traffic conflicts. The results indicated that treated sites had significantly more severe rear-end conflicts that had likely resulted from harder deceleration rates. Speed analysis for DSDSs indicated drivers reduced their speed when they saw their actual speed on DSDSs.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Civil
    Date Created:
    2023

  • Deep Learning and Synthetic Imagery for Migratory Bird Species Identification Using Drones

    Resource Type:
    Thesis
    Creator:
    Costa, Alexsander Cassio Aguiar Antunes
    Abstract:
    In this thesis work, the use of UAS in the study of migratory shorebird species in Canada is explored with the development of computer vision applications. A deep learning classification model is trained to identify the presence of birds of a given species in an image. Images were collected from UAS for the development of the vision models, and realistic models of the species of interest were used. To address a data scarcity issue, the datasets used were augmented with synthetic data with realistic models of the birds. For evaluation of the quality of the artificially generated images, a novel measure is developed. The synthetic image quality measure showed better results in controlled environments when compared to a popular alternative in the literature. The classifiers trained with the augmented dataset showed appropriate performance, with mean accuracy and standard deviation of 94% +- 0.04 in the test set.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Mechanical
    Date Created:
    2023