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"Employee learning satisfaction in Pakistani startups: exploring employee preferences of leader supervision and autonomy based learning"
No full textThis study examines employee learning satisfaction in startups by exploring employee preferences towards leader supervision-based learning and autonomy-based learning. Using a multiple case study approach across six startups in Pakistan, semi-structured interviews were conducted with leaders and employees to understand their learning expectations and the impact of different learning environments. The findings indicate that employee learning satisfaction is significantly influenced by the alignment between preferred and actual learning conditions. Importantly, leader prestige emerged as a critical factor shaping these preferences: employees under highly regarded leaders tended to prefer supervision-based learning, while those in startups led by less prestigious leaders favoured autonomy. These results highlight the practical importance for startup leaders of recognizing and responding to employees’ learning preferences. Aligning leadership styles with these preferences not only enhances learning satisfaction but also contributes to stronger employee engagement and retention within startup environments
Seafloor geological mapping and interferometric synthetic aperture sonar: from mid-ocean ridges to continental shelves
No full textThe Oceans cover 70% of the Earth's surface, yet only 25% have been mapped at a
resolution of at least ~100 m, a resolution that is coarser than the size of many important geological
features on the seafloor, such as hydrothermal vents or volcanoes. On land, geological maps
typically end at the shoreline due to the inaccessibility of the seafloor and challenges of working
underwater (i.e., pressure, light attenuation). Seafloor surveys are carried out using acoustic
techniques, such as sonars, to obtain bathymetric maps and acoustic imagery of the seafloor by
measuring the travel time and intensity of an emitted acoustic signal reflected at the seafloor,
respectively. Seafloor mapping, however, involves a trade-off between data resolution and
coverage, with higher resolutions obtained at the cost of coverage area. Typically, the study of
fine-scale (e.g., 10s of m or less) geological features relies on a multi-scale and multi-tool
approach, combining large-scale acoustic mapping (meter to sub-meter resolution) with fine-scale
optical surveying (millimetre resolution) and sampling of the substrate.
This thesis presents an investigation of the application of different seafloor survey
technologies and approaches for geological characterization of the seafloor. The research focuses
specifically on the study of seafloor hydrothermal vents, which are hot springs on the seafloor that
support life in the deep-oceans, and where metals, including societally relevant base and precious
metals, accumulate as mineral deposits. As a case study, the classic approach to the geological
characterization of a hydrothermal deposit is applied to the Fåvne vent field, located on the Mohns
Ridge in the Norwegian Sea, using 1 m resolution bathymetry, optical imagery, rock samples, and
sediment cores. This study improves our understanding of metal enrichment processes at the
seafloor and extends our knowledge on the global diversity of hydrothermal deposits. With the
development of interferometric synthetic aperture sonar (InSAS), a new high-resolution survey
technology, larger areas of the seafloor can be surveyed at much higher resolutions than using
conventional acoustic techniques. While InSAS has mostly been applied to survey flat terrain, in
this study a comparison of using InSAS on a flat continental shelf to a rugged mid-ocean ridge
terrain is presented. Identification of survey parameters necessary to optimize InSAS data quality
for effective use for scientific applications, shows that InSAS is an appropriate tool for surveys
even in morphologically complex terrain. Through the identification of bedrock structures and
overburden classes from InSAS data, InSAS is evaluated for geological applications, such as
bedrock stratigraphy and tectonics, glacial reconstructions, and marine litter distribution. Overall,
this thesis shows that, compared to conventional techniques, InSAS is an effective tool for high-resolution
characterization of seafloor geological features in various geomorphological
environments, thus opening the door for a significant increase in potential applications, including
for the survey of hydrothermal deposits
Beach-cast brown seaweed (Ascophyllum nodosum) for the extraction of bioactive compounds and production of hydrochar using subcritical water as a green solvent
No full textBeach-cast brown seaweeds are a rich source of potential bioproducts but are currently either left to degrade on coastlines or harvested and discarded in landfills, becoming an environmental burden and resulting in underutilized biomass. This thesis explores the valorization of beach-cast seaweed using hydrothermal processing. A common brown seaweed, Ascophyllum nodosum, abundant along the North Atlantic seashores, is used to investigate lower temperature hydrothermal processing, subcritical water (SCW) extraction as an effective process to produce bioactive compounds (i.e., alginate, fucoidan, phenolics, and carotenoids) in liquid product while simultaneously producing a valuable solid by-product (hydrochar).
A comprehensive literature review identified knowledge gaps in bioactive compound extraction and challenges in scaling SCW processing, guiding the subsequent experimental investigations. The beach-cast A. nodosum was extracted using an Accelerated Solvent Extractor (ASE) under high-pressure SCW conditions (100–200 °C and 100 bar) to evaluate its valorization potential. Experimental design, kinetic studies, and rate modeling identified temperature as the most critical parameter impacting the ASE process. The key bioactive compounds (crude alginate, crude fucoidan, and antioxidant-rich crude extract) and nutrients (minerals and vitamins) exhibited comparable yields and qualities to those reported from fresh seaweeds, demonstrating the feasibility of using beach-cast seaweed as a sustainable feedstock.
The scalability of SCW was studied using a 600 mL bench-scale pressurized reactor under low-pressure SCW conditions (100–240 °C, 1–33 bar). A screening factorial design (SFD) and central composite design (CCD) were used to study the effects of final temperature, hold time at that final temperature, water-to-biomass ratio, water pH, and agitation speed. Final temperature and hold time were identified as the most significant parameters impacting yields and qualities of bioactive compounds and hydrochar.
A key challenge identified in the SCW scale-up is the variability in heating times across reactors, which complicates process optimization and control. To address this, the severity factor (log Ro) was evaluated as a single parameter (0.59–5.10) to integrate final temperature (100–240 °C), heating time (31–99 min), and hold time (0–24 min) for beach-cast A. nodosum valorization. The results demonstrated that the SCW process could recover crude alginate (15.75 dry wt% at log Rₒ = 1.99), crude fucoidan (39.94 dry wt% at log Rₒ = 2.39), antioxidant-rich crude extract (53.84–55.07 dry wt% at log Rₒ = 3.18–3.22), and hydrochar (29.53 dry wt% at log Rₒ = 3.79) at the maximum yields and/or qualities. Characterization of solid and liquid products revealed potential applications across biofuels, animal feeds, diet supplements, cosmetics, and natural antioxidant ingredients.
This thesis establishes a holistic framework for the sustainable valorization of beach-cast seaweeds. By demonstrating the conversion of “waste” A. nodosum into multiple high-value products, the research contributes to regional sustainability, supports zero-waste concepts, and provides practical design tools (i.e., severity factor) for guiding future SCW scale-up and industrial application
To catch an obsession: prevalence and predictors of obsession contagion in individuals with obsessive-compulsive disorder
No full textFor decades, emotional contagion literature has provided evidence that everyday emotions such as fear, anger, disgust, sadness, and joy may transfer from one individual to another. Although previous research has explored contagion of psychological conditions such as depression and anxiety, the spread of obsessions in the context of obsessive-compulsive disorder (OCD) has yet to be examined. This thesis aimed to delineate a potential "obsession contagion" by determining the (1) prevalence and characteristics, (2) potential predictors, and (3) prominent emotional experience in individuals with self-reported OCD. Online survey data was analyzed from 125 adults living in Canada or the United States. The vast majority (85%) reported experiencing obsession contagion in their lifetime, significantly more in-person than online, with an average frequency of twice per month. Regression analyses revealed that susceptibility to obsession contagion was significantly associated with higher participant age, elevated emotional contagion, and lower empathy, with these three variables accounting for approximately half of the variance in obsession contagion total scores. While somatic and aggressive obsessions were particularly "contagious", fear and guilt emerged as the most endorsed emotions in self-reported obsession contagion examples. Clinical implications are discussed, including important considerations for advocacy, assessment, and treatment, as well as the need for future qualitative investigation
Joint optimization of algebraic transformation, device placement, and network bandwidth allocation for distributed DNN training
No full textDeep neural networks (DNNs) have been widely adopted across a broad range of application
domains, including autonomous driving and recommendation systems. To achieve
improved predictive performance, the sizes of training datasets and model parameters
have increased substantially. As the sizes of DNN learning models increase, training on
a single device is impractical due to limitations in memory and computational resources.
To address this challenge, training must be scaled across multiple devices within a distributed
cluster. Therefore, distributed training has been adopted to enable efficient
training of large DNN models in such environments.
Model parallelism is a widely used strategy for distributed DNN training that partitions
model parameters across devices. However, the traditional model parallelism
approach suffers from low hardware utilization because only one device can work at a
time. To improve utilization, tensor, pipeline, and inter-operator parallelism strategies
have been proposed. Among these approaches, inter-operator parallelism necessitates
the optimization of device placement and scheduling to minimize training latency. However,
determining an optimal device placement is an NP-hard problem. As the DNN
model sizes increase, the search space for placement expands exponentially, resulting in
significant placement search latency.
In addition, the communication traffic pattern of a DNN training job is determined
by the parallelization strategy, leading to non-uniform traffic distributions across interserver
communication links. However, traditional Clos-based topologies, which provide
uniform bandwidth and latency, become suboptimal under these conditions. Specifically,
links connecting servers that frequently synchronize may become congested, while other
links remain underutilized. This imbalance leads to poor network resource utilization
and can significantly hinder training performance.
Considering these challenges discussed above, two problems are addressed in this
thesis: 1) with non-uniform traffic distribution in DNN training jobs, how to improve
the network resource utilization to minimize the communication costs, and 2) with the
NP-hard nature of device placement search problem and increased model sizes, how to determine an efficient device placement decision in a polynomial time. First, to improve
network resource utilization, we present joint optimization of device placement and network
bandwidth allocation for the first time to accelerate large-scale distributed DNN
training. We propose a novel approach to implement the network bandwidth allocation.
On each network interface, Open vSwitch (OVS) enforces a Quality of Service (QoS)
policy and corresponding flow rules to route egress traffic and allocate bandwidth for
each destination server. Simultaneously, we leverage policy-based routing with custom
routing tables to simultaneously utilize available bandwidth across multiple physical links
if bandwidth demand from a source server exceeds the capacity of a single link to the
destination server. Second, to tackle the NP-hardness of the joint optimization problem,
we propose a novel algebraic transformation framework based on iterative operator fusion
and co-location. This framework generates a compact representation of the DNN computation
graph, significantly reducing the search space for device placement and network
bandwidth allocation optimization, while incurring minimal performance degradation in
training latency.
We evaluate our approach using real-world DNN benchmarks, demonstrating up to
a 22% reduction in training latency. Incorporating network bandwidth allocation can
provide up to an additional 11% reduction in training latency. More importantly, our
design achieves up to 650 times lower solution search latency compared with state-of-theart
methods
Advancing ecosystem-based fisheries management on the Grand Banks of Newfoundland
No full textTraditional fisheries management has long operated within a single-species lens.
Yet, the persistent degradation of marine ecosystems, loss of biodiversity, and the
consequential decline in ecosystem services highlight the imperative to embrace
new approaches to resource management. This thesis explores various methods
to advance ecosystem-based fsheries management (EBFM) on the Grand Banks
of Newfoundland (3LNO NAFO divisions), flling knowledge gaps on the impacts
of climate change on snow crab, yellowtail founder and Atlantic cod biomass and
distribution, and the role of forage species and top predators on the stability of
the Grand Banks community. By using spatio-temporal models, which capture
spatial and temporal correlations in data and account for species habitat preferences, I detected a northern shift in the average location of biomass for Atlantic
cod, suggesting either a northward movement of the 3NO southern stock or a rapid
recovery of the 2J3KL northern stock. In contrast, the centre of gravity of snow
crab and yellowtail founder have remained relatively stable over time. I also developed new spring biomass indices for these species in the 3LNO divisions. I used
species distribution models to forecast changes in focal species distribution and
biomass by the end of the century. These models use bottom temperature data
from three climate models (GFDL-ESM4, IPSL-CM6A-LR, and ACM) and three
emissions scenarios (SSP1-2.6 and SSP3-7.0/SSP4-6.0) to force the projections.
The fndings suggest that warming is expected to reduce the biomass of snow crab
and yellowtail founder, while increasing the biomass of Atlantic cod, especially
in the 3NO stock. Furthermore, I developed a size spectrum model to evaluate bottom-up versus top-down controls. My fndings indicate that Atlantic cod may
play a more important role than forage fsh in the stability of the Grand Banks
community. Overall, this thesis provides critical insights into the application of
EBFM on the Grand Banks. It emphasizes the necessity for adaptive management
strategies in response to climate-driven changes and highlights the importance of
advanced modelling approaches to understanding complex ecological interactions.Includes bibliographical references (pages 125-155
Coping with prison shift work: interpreting the effects of shift work on correctional officer work-life balance and well-being
No full textThe effects of prison shift work on Correctional Officers9 (COs) work-life balance and
overall well-being are undeniably harmful. In particular, the demanding nature of long working
hours and irregular shift patterns pose wellness and lifestyle challenges for COs. While existing
studies acknowledge the general stresses associated with prison shift work, a notable qualitative
gap exists in relation to the specific effects of shift work on COs' work-life balance and well-being,
as well as strategies for coping. In the current study, I analyze interview data from 48 federally
employed COs in Canada, shedding light on their experiences with shift work strains and their
coping mechanisms. The findings underscore how COs working frequent extended shifts (12 or
16 hours) and night shifts experience difficulties with sleep and work-life balance. Participants
report having little time for extracurricular or self-care activities within their schedules. I put forth
policy considerations for scheduling, given such initiatives are imperative to promoting mental
health and fostering a healthy work-life balance for COs.Includes bibliographical references (pages 20-27
Modeling the Impact of Seasonality on Mosquito Population Dynamics: Insights for Vector Control Strategies
No full textMosquitoes are important vectors for the transmission of some major infectious diseases of humans, i.e., malaria, dengue, West Nile Virus and Zika virus. The burden of these diseases is different for different regions, being highest in tropical and subtropical areas, which have high annual rainfall, warm temperatures, and less pronounced seasonality. The life cycle of mosquitoes consists of four distinct stages: eggs, larvae, pupae, and adults. These life stages have different mortality rates and only adults can reproduce. Seasonal weather may affect the population dynamics of mosquitoes, and the relative abundance of different mosquito stages. We developed a stage-structured model that considers laboratory experiments describing how temperature and rainfall affects the reproduction, maturation and survival of different Anopheles mosquito stages, the species that transmits the parasite that causes malaria. We consider seasonal temperature and rainfall patterns and describe the stage-structured population dynamics of the Anopheles mosquito in Ain Mahbel, Algeria, Cape Town, South Africa, Nairobi, Kenya and Kumasi, Ghana. We find that neglecting seasonality leads to significant overestimation or underestimation of mosquito abundance. We find that depending on the region, mosquito abundance: peaks one, two or four times a year, periods of low abundance are predicted to occur for durations ranging from six months (Ain Mahbel) to not at all (Nairobi); and seasonal patterns of relative abundance of stages are substantially different. The region with warmer temperatures and higher rainfall across the year, Kumasi, Ghana, is predicted to have higher mosquito abundance, which is broadly consistent with reported malaria deaths relative to the other countries considered by our study. Our analysis reveals distinct patterns in mosquito abundance across different months and regions. Control strategies often target one specific life stage, for example, applying larvicides to kill mosquito larvae, or spraying insecticides to kill adult mosquitoes. Our findings suggest that differences in seasonal weather affect mosquito stage structure, and that the best approaches to vector control may differ between regions in timing, duration, and efficacy
Approaches to establishing meaningful partnerships with Indigenous groups: an examination of protocol from eight museums
No full textMuseums are often regarded as respected places of learning; however, they have played a significant role creating and disseminating stereotypes about Indigenous People by misrepresenting them and their cultures. This, coupled with the often violent way that material culture has been collected, has left museums with legacies that can be harmful and unwelcoming to Indigenous Peoples. Indigenous activism both within and outside heritage spheres has led to documents such as UNDRIP, which affirm Indigenous sovereignties and rights to their culture and heritage, and have set a new precedent for how museums should operate and represent Indigenous cultures.
This thesis examines eight museums from across Canada, the USA, and Germany to understand how they are engaging with the Indigenous Nations they represent, and further, how they are counteracting their legacies. This is coupled with the observation of the first stage of Creating Context, a community-project that brought Nunatsiavummiut to Germany to reconnect with material culture in two museum’s care. It was found that the establishment of meaningful relationships is based in trust, and brought to action with three guiding principles (1) ontological empathy; (2) power-shifting and (3) culturally specific care protocol. These themes are foundational in guiding museums toward a better museum practice.Includes bibliographical references (pages 103-115
"Where the old fort was": archaeological mapping and metal detector survey of the Vieux Fort (ChAl-04) in Placentia (Plaisance), NL
No full textThis thesis is focused on the organisation of the Vieux Fort in modern-day Placentia, Newfoundland. The fort served as the main defensive structure in the French colony of Plaisance from 1662 to 1690 but was abandoned following its destruction during an English raid. As the town's only fort, the Vieux Fort served a substantial role in overseeing the safety of its residents and ensuring security for French fishers participating in the cod fishery. Previous archaeological work concerning the Vieux Fort has been almost completely localised to the barracks building, and while this was the central domestic structure on the site and quite possibly the most significant, many features associated with the fort have remained uninvestigated. Understanding more comprehensively the roles that additional structures may have played in the organisation of the fort is crucial to a thorough interpretation of the Vieux Fort and the daily activities that would have taken place within it. In the course of this project, drone-based mapping, metal detector survey, and targeted test pitting of a wide area around the site has been carried out to investigate the aspect and spatiality of the Vieux Fort. Comparative analysis with other contemporaneous French forts and consultation with historical records has guided interpretations concerning the range of activities potentially afforded by the various structures around the site. Improved knowledge of the fort's layout, coupled with artifacts recovered during the course of the research, provides important insight into the lifeways of the fort's inhabitants