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Edge influence on herbaceous plant species, diversity and soil properties in sparse oak forest fragments in Iran
Get PDFPublished versionForest edges have been well studied in temperate and tropical forests, but less so in open canopy forests. We investigated edge influence on plant species diversity and soil properties in sparse oak forest fragments. Data were collected along three transects from the edge to the interior of three small (under 10 ha) and three large (over 10 ha) oak forest fragments in Kermanshah Province, Iran. We measured herbaceous plants (<0.5 m in height) and soil attributes at 0 (forest edge), 25, 50, 100 and 150 m. We quantified species diversity using the Shannon index, used rarefaction to compare species richness between two different sizes of fragments and applied non-metric multidimensional scaling ordination to investigate the variation in species composition. We estimated the distance of edge influence using randomization tests. Generalized linear mixed models with post-hoc Tukey's HSD tests were used to assess the effects of distance from edge and fragment size on diversity and soil properties. We found greater species richness, diversity and evenness at the edge of both small and large fragments and lower nitrogen and organic carbon at the edge compared to the interior of large fragments, with most changes within 50 m of the edge. Species composition, organic carbon and total nitrogen were significantly different between small and large fragments. Our findings of significant edge influence on herbaceous plants and soil properties in these sparse forests provide a significant contribution to the literature on edges, especially in relation to herbaceous plants
Probing high-velocity outflows in active galactic nuclei and their relationship to the inner disc environment with X-ray observations
Get PDF1 online resource (x, 250 pages) : illustrations, charts (some colour), graphs (some colour)Includes abstract and appendices.Includes bibliographic references (pages 242-250).High-velocity outflows in active galactic nuclei usually manifest as either a collimated
jet or diffuse wind. These outflows carry a significant amount of energy from the central
environment surrounding the supermassive black hole into the host galaxy, potentially altering the course of star formation therein. Our current understanding of how these outflows
relate to the central engine, however, remains incomplete. We do not know why some active
galactic nuclei exhibit jets, why some have winds, how either outflow responds to changes
in the conditions of the X-ray emitting region, and if the ones that have no outflows are
intrinsically different systems. In Chapters 2 and 3, I present case studies of two radio-loud
active galaxies with jets, III Zw 2 and IRAS 17020+4544, in an effort to explore the postulated disc-jet connection in such systems using X-ray observations. Spectral and variability
properties in each source suggest that an outflowing X-ray source may act as the jet base.
In a future work, this interpretation will be explored using a sample of both radio-loud
and radio-quiet sources to test its validity. A sample of 20 active galaxies that have been
previously reported as exhibiting ultra-fast winds in their X-ray spectra is used to probe
what underlying driving mechanisms may produce such outflows, as well as how the outflow
properties relate to the conditions of the central engine. We find that wind properties are
closely linked to a variety of source parameters, such as accretion rate and disc inclination
angle. The properties of six extreme accretors may suggest non-standard accretion disc scenarios for which no wind is necessary, highlighting the need to explore alternative models.
Future X-ray missions with enhanced spectral resolution will enable more accurate determinations on the energetics and locations of these extreme winds, which are ill-constrained
with current data
The role of temperate treed swamps as a carbon sink in southwestern Nova Scotia
Get PDFAccepted VersionForested wetlands may represent important ecosystems for mitigating climate change effects through carbon (C) sequestration because of their slow decomposition and C storage by trees. Despite this potential importance, few studies have acknowledged the role of temperate treed swamps in the C cycle. In southwestern Nova Scotia, Canada, we examined the role of treed swamps in the soil C cycle by determining C inputs through litterfall, assessing decomposition rates and soil C pools, and quantifying C outputs through soil greenhouse gas (GHG) emissions. The treed swamps were found to represent large supplies of C inputs through litterfall to the forest floor. The swamp soils had substantially greater C stores than the swamp–upland edge or upland soils. We found growing season C inputs via litterfall to exceed C outputs via GHG emissions in the swamps by a factor of about 2.5. Our findings indicate that temperate treed swamps can remain a C sink even if soil GHG emissions were to double, supporting conservation efforts to preserve temperate treed swamps as a measure to mitigate climate change
The opportunity to be both: a look at Christianity and feminism in Ghana
Get PDF1 online resource (100 pages)Includes abstract.Includes bibliographical references (pages 86-100).This thesis examines the affinity between Pentecostal Christianity and feminism in Ghana.
Feminism has been a topic of debate in Ghana for many years because it is viewed as disruptive
ideology. The role of women is often overlooked within Ghanaian Pentecostal Christian circles.
Women are often not allowed leadership positions in the absence of male leaders, and this is
often backed by literal androcentric biblical interpretations. Such interpretations put feminism
and Ghanaian Pentecostal Christianity as opposing ideologies. However, the biblical passages in
Numbers 27:1-11 regarding the daughters of Zelophehad and that of the women mentioned in
Acts 16: 1-7 when analysed through womanist hermeneutics offer an interpretation that
recognises equality in Ghana’s (Pentecostal) Christianity. The role these women played made
biblical history and the beginning of women’s recognition in Christianity. This thesis examines
the affinity between Ghanaian (Pentecostal) Christianity and feminism using womanist
hermeneutical interpretation
Does the abundance of ectoparasite in the nest affect nestling condition and fledging success?
Get PDF1 online resource (33 pages) : illustrationsIncludes abstract.Includes bibliographical references (pages 27-33).Nestlings of most passerine species face many stressors including early exposure to
ectoparasites. Ectoparasites negatively impact the health of nestlings by feeding on their
blood and feathers, leaving the nestlings in poor condition, and reducing their chance to
fledge. European Starlings (Sturnus vulgaris) are cavity-nesting passerines; they nest in
the holes of trees and artificial nest boxes which accumulate ectoparasites. Parents are
known to line their nest with feathers to serve as a barrier to ectoparasites. Only one study
on the ectoparasite community of European Starlings exists and it was done in Halifax,
Nova Scotia (Fairn et al. 2014). My objectives were to 1) identify the abundance and
types of ectoparasite in starling nests, 2) determine whether ectoparasite abundance
reduces nestling condition and fledging success, and 3) determine whether the mass of
feathers in the nest reduces ectoparasite abundance and to quantify the number of
cigarette butts present in nests. This study was conducted in June 2020 on nine nests from
the late broods of European Starlings. The number of ectoparasites per nest ranged from
8-31. The only ectoparasites found were adult hen fleas (Ceratophyllus gallinae). I found
no relationship between ectoparasite abundance and a) mean nestling condition in the
brood, b) proportion of nestlings that fledged and c) mass of feathers. These results
suggest that nestlings were not affected by this particular prevalence of ectoparasites. It
also suggests that feathers do not serve as a barrier which may instead be present in the
nest to attract the opposite sex. Future studies should examine the effects of different
ectoparasite prevalences on nestlings
The shock of Blitzkrieg : influence, exchange, and development of ideas relating to the use of tanks in the interwar period
Get PDF1 online resource (66 pages)Includes abstract.Includes bibliographical references (pages 63-66).The history of the German Blitzkrieg into France in 1940 often looks at the
German advances as unique and as a surprise to the armies of France and Great Britain. This study considers this image in relation to the spearhead arm of the German advances, the tank. It examines the theory and doctrine behind the use of the tank in the German offensives of 1940, and the origins of these ideas. By comparing developments in Germany with its Second World War opponents such as France and Great Britain we see that the proliferation of ideas regarding the organization and employment of tanks in warfare was widespread. Furthermore, the historical impression of the swift advance of German tanks in 1940 as a surprise to the French or British is revealed as problematic, as these ideas had been widely explored in these nations throughout the interwar years. The exchange of ideas between military thinkers in the interwar period is shown through an examination of the published material and modern historical analysis relating to the development of these ideas in each nation considered
Assessment of a self-learning tool designed to improve mental health literacy of students in higher education
Get PDF1 online resource (58, xv pages) : illustrationsIncludes abstract and appendices.Includes bibliographical references (pages 50-58).Mental health remains a pressing concern for Canadians, especially for those pursuing post-secondary studies. Although the prevalence of mental health issues among this group is well documented, there remains a significant gap in the availability and accessibility of appropriate supports. Increasing mental health literacy levels has been identified as an effective mental health promotion strategy and, to date, the on-campus enhancement of mental health literacy has been hindered by the lack of evidence-based resources. Transitions is the first resource of its kind, designed to improve knowledge of mental health and mental disorders, decrease stigma, promote help-seeking behaviours, decrease feelings of isolation, and increase awareness of supports. The purpose of this thesis is to evaluate the effectiveness of Transitions in improving student mental health literacy by comparing pre- and post-test scores, evaluating whether learning goals were achieved, and investigating the impact of gender and first language on test performance and learning
Graph attention networks for point cloud processing
Get PDF1 online resource (58 pages) : colour illustrations.Includes abstract.Includes bibliographical references (pages 52-58).Three-dimensional point cloud datasets are becoming ubiquitous due to the availability of consumer-grade 3D sensors such as Light Detection and Ranging (LIDAR), and RGB-D cameras. Recent advancements in 3D deep learning has dramatically improved the ability to recognize physical objects and interpret the indoor and outdoor scenes using point clouds acquired through different sensors. This thesis focuses on deep learning based techniques for point cloud processing. We propose novel architectures leveraging graph attention networks for point cloud-based object detection, classification, and segmentation. The proposed architectures work on point cloud scans directly by constructing a connected graph. For point cloud detection, we use the concatenation of relative geometric difference and feature difference between each pair of neighbouring points in the graph. To improve the performance of object detection, we introduce a distance-aware down-sampling scheme for object detection space. For point cloud segmentation and classification, we employ a global aware attention module using global, local, and self feature information. The experiments on different datasets (KITTI, ShapeNet, ModelNet, and Semantic3D) show that our methods yield comparable results for object detection, part segmentation, semantic segmentation, and classification
Leading the way to safety : an investigation of S.A.F.E.R. Leadership
Get PDF1 online resource (vi, 167 pages) : illustrationsIncludes abstract and appendices.Includes bibliographical references (pages 106-143).Work related injuries and fatalities can cause significant human suffering as well as considerable social and economic costs. A growing body of research has demonstrated that leaders can play an important role in enhancing safety at work. However, most studies have relied on existing models of leadership, such as transformational leadership, to investigate the impact of leadership on safety outcomes. Furthermore, most studies have used cross-sectional research designs, which is a gap in the literature considering how the relationships between leaders and followers occur over time. This dissertation aimed to address these gaps over the course of three studies. In study 1, a new scale of safety leadership was developed based on the S.A.F.E.R Leadership Model (Wong, Kelloway, & Makhan, 2015). The S.A.F.E.R Leadership Scale demonstrated good convergent and concurrent validity, as well as incremental validity above and beyond two existing measures of safety leadership. Study 2 adopted a cross-lagged research design to investigate the temporal relationships between safety leadership, safety climate, and safety performance (i.e., safety compliance and safety participation) using a sample of transit workers. The findings suggest that S.A.F.E.R leadership predicts safety climate and performance over time, demonstrating predictive validity, and the direction of causality is from S.A.F.E.R leadership to the outcomes, and not vice versa. Study 3 also adopted a temporal design, examining impact of workload on S.A.F.E.R leadership in a training context. An analysis of the post-training growth trajectories of workload and S.A.F.E.R leadership suggested that workload was not a barrier to transfer of training for nurse leaders. Taken together, this dissertation demonstrates that the S.A.F.E.R Leadership Model is a viable model of safety leadership that is different from the existing conceptualizations of safety leadership, and provides a psychometrically sound measure of S.A.F.E.R Leadership that can be used in training to enhance safety behaviours and outcomes in organizations
Towards a productive relationship between police and community safety leaders in racialized socially disadvantaged neighbourhoods : measuring the impact of formal, partnership-based community crime prevention organizations
Get PDF1 online resource (xii, 180 pages) : chartIncludes abstract and appendix.Includes bibliographical references (pages 141-180).The goal of this research is to explore the extent to which the implementation of a partnership-based
(“co-production of safety”) model in a racialized socially disadvantaged neighbourhoods (SNDs) affects the relationship between community safety leaders (CSLs) and police, with particular emphasis on how it influences the perceptions of and satisfaction with police by local CSLs. The study concludes that the Mulgrave Park Community Mobilization Team (MPCMT) has helped to
bridge the gap between police and local CSLs. The MPCMT appears to have helped give the CSLs more authority which include opportunities for them to hold police accountable for their actions.
Despite the minimal improvements in the relationship between police and the CSLs, there is no
evidence that the MPCMT had any impact on institutional racisms within the HRP