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Deleuze and evolution: the relevance of differential ontology for investigating biological complexity
No full textThis thesis aims to demonstrate the relevance of the work of Gilles Deleuze, particularly Difference and Repetition to the field of evolutionary biology. I argue that Deleuze's differential ontology provides a valuable philosophical basis for contemporary approaches to evolutionary science. To do this, I analysed the work of Richard Dawkins and Stephen Jay Gould from a Deleuzian perspective. In doing so, I demonstrate that Dawkins' view is implicitly premised upon the kind of identitarian thinking that Deleuze effectively critiques. Likewise, I argue in favour of Gould's approach as an example of how evolutionary science can avoid these shortcomings, precisely because Gould's attitude towards nature is strikingly comparable to the ontology of nature presented in Difference and Repetition. This allows for a detailed discussion of emergence and complexity in molecular biology in order to demonstrate the strengths of Deleuzian ontology for addressing these issues. My criticism of Dawkins in favour of Gould and my exploration of a Deleuzian approach to emergence and molecular biology serve to demonstrate that contemporary evolutionary theory would benefit enormously by closely engaging with Deleuze's oeuvre, particularly Difference and Repetition
Inferential methods for adaptive group sequential design in clinical trial
No full textThe group sequential designs of Randomized Clinical Trials collect data in stages and perform
interim analysis or modification during the trial for various purposes. The balanced treatment
allocation in group sequential designs raises ethical concerns, as it may expose half of the patients
to potentially inferior or unsafe treatments. One potential modification from an ethical perspective
could be the decision regarding treatment assignment for the subsequent stages. We propose
an adaptive group sequential design by using information on treatment effects accumulated during
the trial to modify treatment allocation in order to assign fewer patients to the potential
inferior treatment arm. However, interim modification of a trial can increase the Type-I error
rate. To address this, we propose a weighted t-test and derived formulas for establishing the
critical values to control the inflation of Type-I error rates, and we also modify traditional twosample
t-test. We conduct simulations to examine the performance of the inferential methods
and the adaptive group sequential allocation. Simulation results indicate that the proposed test
methods preserve the Type-I error rate and the proposed group sequential design with adaptive
treatment assignment has the ethical advantage of reducing the number of patients exposed to
inferior treatment.Includes bibliographical references (pages 50-54
Understanding the relationship between perceptions of social power and social mobility beliefs
No full textThis research examined the relationship between perceived social power and social mobility beliefs through two complementary studies. In Study 1, the association between perceived power and personal and societal social mobility beliefs was examined in a large, cross-national dataset, while controlling for various individual and societal-level factors. Results revealed a small positive association between feeling more powerful and beliefs about the likelihood of changing personal social class. A similar but even smaller pattern was found for beliefs about the chances of societal social class change. Study 2 employed an experimental design to test whether power could influence participants' beliefs about social mobility. A manipulation of power successfully increased perceived power and opportunity in the high-power as compared to the low-power condition. Relative to low-power, the high-power condition showed a small effect on higher personal mobility beliefs, although this pattern did not reach statistical significance. The same pattern was not detected for societal mobility beliefs. Across both studies, findings suggest that feelings of influence over others may help explain personal beliefs about social class change. Implications for our understanding of social mobility beliefs and perceptions of social power are discussed
Accessible ocean monitoring technologies in developing countries: NF-POGO global scholar perspectives on low-cost solutions
No full textPublishe
Chromatography-mass spectrometry-based identification of triterpenes and phenolic compounds in Maskwio’mi (Betula papyrifera Marshall bark extract)
No full textMaskwio`mi is a traditional topical treatment used by the Mi`kmaq people to treat a variety of skin conditions, including eczema and psoriasis. It is typically obtained through the pyrolysis of Betula papyrifera Marshall (paper birch) bark via a can-over-can method. To replicate those conditions under controlled settings, a pyrolysis reactor system developed by Dr. Bierenstiel was used to recreate the production of maskwio`mi in the laboratory. The resulting bio-oil, also referred to as an extract, is formed of a complex mixture, containing hundreds of organic compounds, which makes it challenging to characterize. Chromatography coupled with mass spectrometry is the common technique used for bio- oil composition analysis. This approach has been applied to Betula species analysis, which led to the identification and subsequent isolation of bioactive compounds, including triterpenoids and phenolic compounds. Although some of these compounds can have therapeutic effects, certain phenolic compounds, such as cresols, are recognized as environmental pollutants due to their toxicity and potentially harmful effect on humans and animals, which necessitates their accurate identification and quantification in bio-oil samples.
This thesis presents the identification and quantification of phenolic compounds and lupane-type triterpenes. First, the concentrations of ortho-, meta-, and para-cresol were found to be from 324 to 1,240 mg/L using a full-scan GC-MS method. Selected reaction monitoring (SRM) was employed to quantify nine compounds, which ranged from 192 to 5,909 mg/L. Furthermore, betulin and betulinic acid were quantified at concentrations of 2,411 ± 45 ppm and 199 ± 8 ppm using a UHPLC-MS method.Includes bibliographical references (pages 65-83
Tongues and interpretation (poems)
No full textTongues and Interpretation is a poetry manuscript that explores the effects of
growing up in a religious household where one is left to navigate the aftermath of
conservative, dualistic thinking on one's experience with the environment, gender, and
culture. This collection focuses intensely on the material world while also skirting along
the edge of scripture and myth, engaging with sacred stories not to discount them, but to
digest them with levity, grief, and reverence. It examines the images and memories of a
childhood where moose hearts floated in Tupperware and rabbits hung, skinned, in the
basement; where children spent Sundays in ancient texts that brimmed with violence and
devotion and weekdays deep in turr feathers and cod guts. The collection engages with
ideas of creation and decreation, rewilding the body, and unsettling religious text —
listening to and speaking with the tongues of feminism, hunting, Sunday dinners, plastic
pollution, evangelicalism, body politics, and Newfoundland folklore. Tongues and
Interpretation explores the grotesque and the beautiful, making a case for the reverence
needed amid revulsion and blurring the line between the sacred and profane in a bid to
call humans into a better relationship with all animate/inanimate objects and
human/nonhuman beings of the world
Adaptive spatial and temporal integrators for heat conduction problems
No full textWe explore temporal and spatial adaptivity for approximating solutions to differential
equations. We discuss temporal adaptivity applied to Runge-Kutta in time and
finite-element in space approximations to solutions of time-dependent partial differential
equations under the method-of-lines framework. For heat conduction problems,
we discover that using an adaptive time-stepper more efficiently models the transition
to the steady state than fixed time-steppers. We also measure the quality of adaptive
step size controllers, implementing a bisection algorithm that finds the largest
acceptable step size for a given tolerance.
We also explore spatial adaptivity for finite-element solutions of partial differential
equations. We find that physical problems can be resolved through high-resolution
uniform grids or smaller grids better adapted to the problem. We compare both
approaches by implementing a moving spatial grid through the curvilinear coordinate
system, allowing us to map between spatial and computational grids. We then explore
the parameters of the monitor function, which shifts the mesh points toward regions
of either high curvature or high arc length
Unmasking SARS-CoV-2 ORF3a; a hidden trigger of immune overdrive in COVID-19
No full textCoronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2), became a global health crisis in 2020, leading to widespread severe
cases. The severe cases are often linked to an overactive immune response that is characterized by
excessive release of pro-inflammatory cytokines. SARS-CoV-2 can abortively infect lung-resident
macrophages, leading to inflammasome activation and the release of pro-inflammatory cytokines,
which often escalates into a cytokine storm, driving COVID-19 pathology. However, the
mechanism of inflammasome activation in macrophages during SARS-CoV-2 infection remains
unclear. Here, we demonstrate that SARS-CoV-2 open reading frame 3a (ORF3a) significantly
activates inflammasome in THP-1-derived macrophages (TDM), resulting in the secretion of IL1β and IL-18 cytokines, whose elevated levels correlate with COVID-19 pathogenicity. This
provides insight into inflammasome activation and heightened innate immune reaction seen in
severe cases of COVID-19. While the ORF3a-transfected A549 lung epithelial cells did not release
significant amounts of IL-1β, their supernatant was sufficient to induce robust inflammasome
activation in TDM. This ability of epithelial cells to promote inflammasome activation in immune
cells, even when they are not the primary source of inflammatory cytokines, sheds light on the
process of macrophage activation syndrome (MAS), cytokine storm, and systemic inflammation
in severe COVID-19. Taken together, we show that ORF3a plays an important role in the
pathogenesis of SARS-CoV-2, and targeting ORF3a could be an effective therapeutic strategy to
target both the virus and the disease, given ORF3a’s role in virus production
The mental health needs and healthcare system experiences of perimenopausal women in Newfoundland & Labrador
No full textThis ethnographic study examines the mental health needs and healthcare system experiences of perimenopausal women in the Canadian province of Newfoundland and Labrador. The researcher's lived experiences, coupled with literature, prompt the question of public health effectiveness in addressing perimenopause mental health. With a feminist, social constructivism lens, the study explored possible gaps in the Newfoundland and Labrador public health system regarding perimenopause mental health. A mixed methods study comprising an online survey and virtual focus groups investigated how women addressed their psychological well-being during perimenopause and the effectiveness of those strategies. Seventy-five women completed the survey, and six women participated in the focus groups. The study revealed that women often did not receive adequate care for perimenopause symptoms, particularly regarding mental health, and women's mental health experiences during perimenopause worsened as a result. This study can stimulate dialogue among NL public health to address any existing gaps in this area
Large diameter drilling performance modelling - experimental and empirical approaches
No full textAccurate modelling and optimization of large diameter drilling performance is critical in the efficient planning and delivery of large diameter drilling projects like tunnel boring and raise boring. A recently proposed application of large diameter drilling is narrow vein mining. This innovative technique results in continuous mechanized excavation of narrow vein deposits. This thesis presents experimental and empirical investigation into large diameter drilling performance. The research started with rock property characterization: shale volume prediction and rock mass mechanical properties evaluation. An extensive literature review shows no correlation has been developed in the Niger Delta Basin to accurately predict shale volume based on gamma-ray logs. Additionally, no published work shows the evaluation of the mechanical properties of the rock mass in the field site. From work conducted as part of this research, rock mass properties were evaluated for the site. Another contribution to be made by this research is the investigation of disc cutter drilling performance at small installation radii using a rotary cutting machine. This study complements several studies on disc cutting drilling performance using linear cutting. The final scope of the research was the modelling of large diameter drilling performance using results obtained from a Full Field Trial conducted on a steep quartz vein-host rock system. The different empirical models initially developed during the research were deterministic, however, probabilistic models were proposed to capture the existing aleatory and epistemic uncertainties. The thesis concluded with showing the implication of large diameter drilling as a new narrow vein mining method on the comminution energy requirements during mineral processing