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Controls on surface ozone concentrations and local production in the North American pollution outflow region of Nova Scotia
Get PDF1 online resource (vii, 111 pages) : colour illustrations, colour mapsIncludes abstract.Includes bibliographical references.High concentrations of tropospheric ozone are a concern due to its detrimental effects on human and plant health. As the world population expands and ozone precursor emissions become more challenging to limit, understanding the drivers of ozone production is necessary to minimize ozone concentrations. This research analyzed the relationship between ozone concentrations and precursor emissions in Nova Scotia to explain long term decreasing ozone concentrations (99th percentile and median total ozone) alongside very recent rising ozone concentrations at stations across the province. This project calculated long-term trends of ozone, its precursors and transported pollution frequency, and examined variables leading to elevated ozone concentrations in Halifax where production was found to be limited by volatile organics. A novel method for diagnosing pollution transport days was developed and applied to estimate the frequency of transboundary air pollution in the province as 45-63% of elevated ozone days in Halifax, increasing over the study period
2021-12-17 Senate Minutes and Agenda
No full textMinutes and agenda for the December 17th, 2021 meeting of Saint Mary's University Senate
Criminal trajectories of adult-onset sex offenders
Get PDF1 online resource (74 pages) : illustrationsIncludes abstract.Includes bibliographical references (pages 55-65).Previous research has suggested that a subset of adult-onset sexual offenders (AOSOs) may be at an increased risk for re-offending against children. Despite this evidence, research on the trajectories of AOSOs is limited. The present study examines the offending trajectories of 520 AOSOs who were assessed at an out-patient mental health facility between 1995 and 2006. Four groups were identified in the sample using group-based trajectory modeling and were compared on the presence of three indicators of a sexual interest in children, victim characteristics, and a variety of additional criminal career parameters. A group with an escalating pattern of offending with onset in early adulthood was found to be associated with all three indicators of a sexual interest in children, and a high frequency of sexual offending. The three additional groups, as well as implications for policy, treatment, and future research are discussed
Python tools for the investigation of optimal explicit runge-kutta methods
Get PDF1 online resource (128, 2 unnumbered pages) : chartsIncludes abstract and appendix.Includes bibliographical references (page 92).The investigation of many real-world applications involves mathematical models that consist
of systems of ordinary differential equations (ODEs). This thesis mainly focuses on the ODEs
with the initial values known as initial value ordinary differential equations. These equations
are typically solved using numerical methods to obtain approximate solutions. A popular class
of numerical methods to solve an initial value ODE are the Explicit Runge-Kutta (ERK) methods.
This thesis considers Python software for the investigation of ERK methods. ERK methods can
be used to obtain approximate solutions at a discrete set of points across the domain of
interest, with ℎ being the distance between the points. An ERK method is said to be of order
if the error of the numerical solution is proportional to ℎ
. In this thesis, we consider Python
software for the determination of optimal ERK methods of orders 1 to 4. The Python software
also has the capability to solve a set of test problems using various ERK methods in order to
allow for a comparison of the accuracy of the numerical solutions obtained from the ERK
methods. The Python software can also be used to extend the discrete approximate solutions from the ERK methods to obtain continuous approximate solutions over the entire domain using Hermite interpolation. To assess the accuracy of the continuous solution approximation,
the software can also be used to compute the defect of the continuous approximate solution,
where defect is the amount by which the continuous approximate solution fails to satisfy the
ODE
Weird narrow-line seyfert 1s: A multi-epoch, broadband analysis to study the x-ray emission in mrk 1239 and wkk 4438
Get PDF1 online resource (ix, 101 pages) : charts, graphsIncludes abstract.Includes bibliographical references (pages 92-101).X-ray emission from Seyfert 1 galaxies has a debated origin. The primary X-ray source
is the compact corona, but the secondary X-ray emission is thought to originate from either
a Comptonising layer or blurred reflection from the accretion disc. Finding objects that do
not fit into this standard framework are important for understanding the class as a whole. We
examine broadband, multi-epoch data of two atypical NLS1s, Mrk 1239 and WKK 4438. While
both objects are defined as Seyfert 1s based on optical classification, their X-ray emission is
poorly understood. We use broadband multi-epoch spectroscopy to model X-ray emission and
examine the timing properties of both galaxies. In Mrk 1239 we determine that the spectra are
consistent with high absorption and emission from a distant starburst component. In WKK 4438,
we discover excess emission above 30 keV, that may point to a jet origin. Blurred reflection and
Comptotnisation fail to describe either object indicating the standard paradigm for the X-ray
emission cannot be applied universally
2021-04-16 Senate Minutes and Agendas
No full textMinutes and agenda for the April 16th, 2021 meeting of Saint Mary's University Senate
A Conversation with Lynn Jones on the Lynn Jones African-Canadian & Diaspora Heritage Collection
No full textSupplied by Saint Mary's University Archives.Colour video with audio.In this 30-minute video Saint Mary's University introduces a compilation of Dr. Lynn Jones' memories of historical and ongoing occurrences in the Global Black Community. Highlighted is the legacy of the African Nova Scotian, African and Diasporic lived experiences now available to the public in the Lynn Jones African Canadian & Diaspora Heritage Collection. Lynn Jones introduces her creation of "the Collection" and provides an overview and illustrative samples of materials in it, from 1928 into more recent years.</p
Public engagement with historical burying grounds in Halifax, Nova Scotia
Get PDF1 online resource (iv, 46 pages) : illustrations (some colour)Includes abstract.Includes bibliographical references (pages 44-46).This thesis examines public engagement with three historical burying grounds in downtown Halifax, Nova Scotia: The Old Burying Ground, the Poor House burying ground, and St. Peter’s Cemetery. The research question was inspired by a significant event in 1958 where the Downtown Merchants Association proposed to turn the Old Burying Ground into a parking lot (McGuire 1990). This was met by serious opposition from the public, even with the promise by the Merchants Association to provide a suitable monument on the site to acknowledge its history and significance. This is important because it does not appear that the other cemeteries received the same opposition as they underwent transformations in the twentieth century, such as the construction of a library and the paving of a parking lot. Through the use of newspaper articles from the nineteenth and twentieth centuries, modern news coverage, social media comments and news article comments, I provide a timeline of events related to the sites. Through this timeline, I explore notable themes and similarities of how people have expressed opinions and interests in the burying grounds from the nineteenth century to present. The results of this research suggests that the reasons for maintaining and memorializing the Old Burying Ground in comparison to its neighbours is related to the level of preservation the site holds and its military associations, but also the larger ideas of power that dominate the site
Freshwater tolerance of fourspine stickleback (Apeltes quadracus) marine and lake populations
Get PDF1 online resource (48 pages) : illustrations (chiefly colour), colour mapIncludes abstract.Includes bibliographical references (pages 42-48).Fishes have evolved freshwater tolerance multiple times, using different physiological mechanisms, and we have much to learn about how fish can adapt to freshwater. Sticklebacks in the family Gasterosteidae are becoming an important model system in which to study the evolution of freshwater tolerance. In this study I measured freshwater tolerance of a freshwater (lake) and a marine population of Fourspine Stickleback (Apeltes quadracus) to test overall tolerance in this species and determine if there is evidence of freshwater adaptation in the lake population. To assess tolerance, both populations acclimated to near isosmotic water (10 ppt) and were exposed to an acute freshwater (0 ppt) challenge and monitored over 48 days of freshwater acclimation. Survival, body water content, tissue ion content and standard metabolic rate were measured from fish from both populations during the study. We found that both the marine and lake populations were able to cope with freshwater transfer, as both had high survival rates and could maintain body-water homeostasis. My data suggests that ancestral Fourspine Stickleback that were landlocked at the end of the last ice age may have had higher freshwater tolerance than some other Gasterosteidae species, allowing them to easily colonize post-glacial lakes