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Sodium iodate response in ARPE-19 cells: an In vitro model of age-related macular degeneration
Get PDFWith the rise in aging populations worldwide, diseases of the eye like age-related
macular degeneration (AMD) will continue to rise and the need to investigate ways to
slow down the progression of the disease are at an all-time high. AMD exists in two
forms, the slower and less invasive dry form and the more aggressive wet form which
can lead to a rapid loss of vision in patients diagnosed. This study aims to investigate
the role of oxidative stress and the ability to use natural antioxidant compounds as a
means of reducing oxidative stress and mitigating further damages in AMD. This study
also aims to further investigating the role of gene knockdowns in cytoprotection of
human retinal pigment cell line (ARPE-19 cells) pre-treated with natural antioxidant
compounds. A wild-type ARPE-19 cells (WT) was used as an in vitro model of AMD to
investigate the use of antioxidant compounds to mitigate oxidative stress damages.
Resveratrol, pterostilbene, lutein, punicalagin, loganin, chebulagic acid, beta-carotene,
and zeaxanthin were investigated in the cell culture model as a means of offering
cytoprotection to ARPE-19 cells exposed to blue light and sodium iodate (SI), both used
as inducers of oxidative stress. [...
Empowering educators: perspectives and confidence levels of teacher candidates in digital media literacy
Get PDFIn today's rapidly evolving digital landscape, digital media literacy emerges as an indispensable
skill that extends beyond the confines of formal education and permeates everyday life. There is
a significant gap in current research regarding the state of digital media literacy in Ontario,
particularly focusing on the perspectives and confidence levels of teacher candidates in
teaching this competency. Digital media literacy in education is crucial as it equips students with
the critical skills needed to navigate and participate in the digital landscape, fostering informed
and responsible digital citizenship in a democratic society. This thesis analyzes the current
landscape of digital media literacy education in Ontario by drawing conclusions from two distinct
datasets. First, it examines research data generated for a report for the Privacy Commissioner
of Canada, focusing on the integration of online privacy education within the K-12 curriculum in
Ontario. This analysis establishes current expectations and benchmarks for DML in the
province. The second dataset comprises responses from Lakehead University teacher
candidates to the end-of-year survey titled "Operation Happy To Be Here" (OH2BH). This
survey, to which I contributed questions and organized data as a research assistant, evaluates
candidates' self-reported comfort levels in imparting essential media literacy competencies, with
a specialized focus on data privacy awareness and AI use. By synthesizing findings from both
the Privacy Commissioner's report and the OH2BH survey, this thesis offers a comprehensive
overview of how digital media literacy is currently being taught in Teacher Education programs
in Ontario. It demonstrates that teacher candidates are not always emerging from these
programs with the confidence and preparedness necessary to teach this critical competency.
This comparative analysis aims to highlight gaps and propose actionable strategies for
enhancing digital media literacy education, ensuring that future educators are well-equipped to
foster digital literacy and responsible digital citizenship among their students
Estimation and detection theory in visible light communication systems: a perspective on realistic receivers
Get PDFVisible light communications (VLC) has been proposed as a promising way for nextgeneration
wireless communication networks to mitigate the scarcity of the radio
frequency (RF) spectrum, and has consequently attracted much attention. Accordingly,
this thesis investigates single-input single-output (SISO) VLC when subject to signaldependent
shot noise (SDSN). Firstly, we consider the case of fixed-location user located in
an indoor environment. For instance, in a classroom setting, a teacher may utilize VLC to
transmit lecture notes and supplementary materials to students’ tablets or laptops, ensuring
a seamless exchange of information without the need for traditional wireless networks.
The topics of discussion include channel estimation and data transmission, where in the
former, we introduce both least square (LS) and maximum likelihood (ML) estimators.
The Cramér–Rao lower bound (CRLB) of the channel estimation error is also derived.
In terms of data transmission, we propose optimal and sub-optimal receiver designs and
present their bit error rate (BER) performances. In specific, we derive a closed-form
expression of the BER for the sub-optimal receiver and an approximated version for the
optimal one. Our analysis indicates that the performance of the CRLB demonstrates no
linear relationship with the SDSN, thermal noise, or fading channel gain. On the other
hand, SDSN has quite a severe effect on the channel estimation error bound, and as such,
it can dramatically degrade the BER performance. Heightened performance degradation
can also be explained by the joint effects of the channel estimation error and SDSN.
Secondly, we consider the case of random location of the user located in an indoor
environment, such as a conference room within a corporate office where the user may
move around freely during a meeting or presentation. In particular, the second part of
this research estimates the channel of the considered system using ML, LS, linear minimum
mean square error (LMMSE), maximum posteriori probability (MAP) and minimum mean square error (MMSE) estimators. Furthermore, a Bayesian Cramér-Rao lower bound
(BCRLB) is derived for the proposed system and it is compared to the mean square error
(MSE) of the proposed estimators. The problem of the unknown SDSN factor at the receiver
side is discussed and two solutions are investigated. The receiver of a VLC system
under SDSN and random channel gain is designed and its BER is studied. Monte Carlo
simulation results of the proposed estimators, which show the dramatic effect of the SDSN
on the considered system, are provided. In particular, the presence of noise variance, as
well as the SDSN factor, causes an increase in the MSE of the system, while increasing the
power reinforces the system performance.
Moreover, the third part of this research explores the interplay between SDSN and
another inherent noise in the light source called relative intensity noise (RIN), revealing
their combined adverse effect on channel estimation accuracy in a VLC system. Towards
this direction, we first derive CRLB in the presence of the SDSN and the RIN, which
gives a lower estimate for the variance of an unbiased estimator. Then, we present the
derivation of LS and ML channel estimators. Furthermore, we present the optimal receiver
in ML sense and compare it with a simple threshold detector as a sub-optimal solution,
quantifying the impact of channel estimation accuracy on both receivers. The findings
presented in this part reveal that the RIN and the SDSN jointly have a significant adverse
effect on the VLC channel estimation, consequently leading to a pronounced degradation in
BER performance of the VLC system. In addition, we proposed optimal and sub-optimal
receiver designs and present their BER. The Monte Carlo simulation results of the BER
for the two presented receivers show that the optimal receiver performance excels beyond
the performance of the sub-optimal receiver.
In other words, our study focuses on investigating the effects of signal-dependent noise in
VLC systems. Initially, we explored how SDSN impacts VLC systems serving fixed-location users. Subsequently, we delved into the influence of SDSN in scenarios where channel
gain variability arises from the randomness of user locations. Following, we analyzed
the combined impact of SDSN and RIN on the performance of VLC systems catering to
fixed-location users in indoor environments. Our investigation involved the use of various
channel estimation techniques, which were compared against a derived lower bound to
evaluate their performance. Additionally, we designed different receivers to demonstrate
how such noise affects the BER of the considered VLC systems
Decolonizing environmental science education: (Re)storying relations for settler educator unsettling
No full textThe purpose of this portfolio is to emphasize, demonstrate, and role-model the inherent
responsibility that all settler educators have in decolonizing their own ways of knowing, being,
doing and belonging before they can respectfully and ethically decolonize their pedagogies of
any subject, including environmental science education. Settler educator decolonization is
necessary for teachers to become active, engaged and informed treaty partners who then fulfill
treaty obligations to “ka-miyo-ohpikihitoyahk (for us to raise each other’s children well), learning
from each other in balanced ways and sharing wisdom that comes from living together in the
spirit of good relations” (Donald, 2022, para. 15). Consequently, the portfolio’s self-study
purpose is two-fold: (i) to challenge and document my personal un/re-learning1 as a settler
educator and visitor on Treaty 7 territory, in order to (ii) help encourage/guide/motivate/support
settler (science) educators’ “stamina” (Stein et al., 2021, p.1) through their own unique
decolonizing journeys; a stance of affective-cognitive-reflexive awareness and examination,
required for a lasting decolonizing engagement and commitment to reconciliation
Situational peer preferences within the dark triad and light three: peer selection and ranking
No full textThe Dark Triad is a trio of socially aversive sub-clinical personality traits consisting of narcissism, Machiavellianism, and psychopathy. The Light Three is a grouping of three prosocial sub-clinical personality traits including empathy, altruism, and compassion. Benchmarks of these personality traits are their unique HEXACO profiles. The HEXACO model of personality structure includes six domains: Honesty-Humility, Emotionality, eXtraversion, Agreeableness, Conscientiousness, and Openness to Experience. Previous research has explored the implications that these personality traits have on various contexts such as employment, friendship, and romantic relationships, as well as assortative mating preferences. The purpose of this investigation was to explore peer preference as a function of personality and biological sex in the contexts of friendship, teamwork, and financial trust. A secondary focus of this study was to further validate the Dark Triad and Light Three to support that these are unique and independent concepts. [...
Ground improvement of non-cohesive soil using nanoparticles, specifically, laponite
Get PDFGround improvement through densification is a widely used techniques to mitigate the risk of
liquefaction and significant soil deformations. Traditional site stabilization techniques have certain
limitations such as insufficient field treatment, substantial disturbances, environmental pollution,
and high costs. However, incorporating nanoparticles into ground improvement techniques can
lessen these negative impacts, offering a more efficient and environmentally friendly alternative.
This study examines the characteristics of laponite, a promising soil improvement nanoparticle,
when it is mixed with non-cohesive soil under full saturated conditions. The findings revealed that
laponite is both environmental-friendly and biologically inert. Even a small amount of laponite
significantly reduces the generation of pore water pressure under static loadings due to its good
rheological properties as a transparent gel. Additionally, the modulus of elasticity of sand-laponite
specimens is nearly double that of pure sand. The swelling strain of compacted laponite increases
over time and as the concentration of laponite increased in specimens. Laponite also effectively
restricts the migration of contaminants and reduces soil permeability due to its repeated swelling
performance. Moreover, the damping ratio of treated samples is higher compared to untreated sand
samples. The damping ratio begins to reduce after reaching its peak and eventually reaches
equilibrium in case of sand+ laponite samples. The coefficient of permeability is significantly
reduced with the presence of small amounts of laponite in sand samples. The compressive
behaviour of laponite hydrogel indicates that laponite hydrogels exhibit the nonlinear stress-strain
relationships which represents typical viscoelastic characteristics. This research provides novel
insights into the improvement and modification of the properties of non-cohesive soil (sand)
elaborately in the presence of laponite, demonstrating its potential as an effective ground
improvement material
Symptoms of premenstrual dysphoric disorder and cycle phase are associated with enhanced facial emotion detection: An online cross-sectional study
Get PDFThe authors wish to thank Chyenne Panetta and Nandini Parekh who helped with the organization and sorting of the data for the FEDT. Some of the data in this paper were reported in the MA thesis of the first author.Background: Premenstrual dysphoric disorder is a depressive disorder affecting 5%–8% of people with menstrual
cycles. Despite evidence that facial emotion detection is altered in depressive disorders, with enhanced detection of
negative emotions (negativity bias), minimal research exists on premenstrual dysphoric disorder.
Objectives: The goal of this study was to investigate the effect of premenstrual dysphoric disorder symptoms and the
premenstrual phase on accuracy and intensity at detection of facial emotions.
Design: Cross-sectional quasi-experimental design.
Method: The Facial Emotion Detection Task was administered to 72 individuals assigned female at birth with no
premenstrual dysphoric disorder (n=30), and provisional PMDD (n=42), based on a retrospective Diagnostic and
Statistical Manual of Mental Disorders—Fifth Edition-based measure of premenstrual dysphoric disorder. Facial emotion
detection was examined both irrespective of menstrual cycle phase, and as a function of premenstrual phase (yes, no).
The task used neutral-to-emotional facial expression morphs (15 images/morph). Participants indicated the emotion
detected for each image within the progressive intensity morph. For all six basic emotions (sad, angry, fearful, happy,
disgust, and surprise), two scores were calculated: accuracy of responses and the intensity within the morph at which
the correct emotion was first detected (image number).
Results: Individuals reporting moderate/severe symptoms of premenstrual dysphoric disorder had more accurate and
earlier detection of disgust, regardless of cycle phase. In addition, those with provisional premenstrual dysphoric disorder
detected sad emotions earlier. A premenstrual dysphoric disorder group×cycle phase interaction also emerged:
individuals reporting premenstrual dysphoric disorder symptoms were more accurate at detecting facial emotions during
the premenstrual phase compared to the rest of the cycle, with a large effect size for sad emotions.
Conclusion: The findings suggest enhanced facial emotion processing in individuals reporting symptoms of premenstrual
dysphoric disorder, particularly for sadness and disgust. However, replication is required with larger samples and
prospective designs. This premenstrual dysphoric disorder premenstrual emotion detection advantage suggests an
adaptive cognitive mechanism in premenstrual syndrome/premenstrual dysphoric disorder, and challenges stigma
surrounding premenstrual experiences
Identifying mental health indices among Indigenous and non-Indigenous Treaty three police service officers
Get PDFBackground: Police officers are essential frontline workers tasked with protecting our communities. They are susceptible to adverse mental health exposures, outcomes, and barriers to accessing supports, which may increase their risk of developing mental health problems. In Canada, police officers serve communities municipally, provincially, and federally. In Northwestern Ontario (NWO) self-administered, Indigenous police services are employed to service Northern communities (i.e., Treaty Three Police Service: T3PS). The confluence of contextual factors that exist in Northern communities may contribute to differential exposures that may result in heightened mental illness among these officers. Research Purpose and Objectives: The overarching purpose that guided this study was to identify mental health exposures, adverse mental health outcomes, and barriers to accessing mental health supports among Indigenous and non-Indigenous T3PS officers. Collectively, for the purpose of this study, these indices encapsulate the term “mental health status.” The study purpose was guided by two research objectives including to: (1) determine the mental health status of T3PS officers, and (2) identify the barriers to accessing mental health supports; as experienced by these officers. Methodology: To determine T3PS officers’ mental health status, a battery of questionnaires were administered including: the Critical Incident History Questionnaire for Police Officers (CIHQ), the Brief Trauma Questionnaire (BTQ), and the Post-Traumatic Stress Disorder Checklist from the Diagnostic and Statistical Manual of Mental Health Disorders, 5th Edition (PCL-5). To address the second study objective, the Self Stigma of Seeking Help Scale (SSOSH scale) was administered. Results: T3PS officers were exposed to work-related (Median= 120; Interquartile Range= 160.75) and non-work-related (Md=3; IQR=3) mental health exposures. [...
Urban forest management: evaluating the benefits and options for replacing declining urban ash tress, and value-added potential of urban trees
Get PDFThis thesis investigates the benefits and options for replacing declining urban ash
trees, as well as the value-added potential of urban trees more broadly. The study aims
to provide insights into the selection of suitable tree species for urban areas, considering
their ecological, social and economic benefits. The research methodology involved a
literature review of various peer-reviewed articles, government sites and books to assess
the survival rate of different tree species and their growth patterns in urban areas. The
study also analyzed the value-added potential of selected tree species in terms of
ecosystem services, such as carbon sequestration, air quality improvement, and aesthetic
value. The study also analyzed the approaches used by different cities to replace ash
trees and suggested new species to plant. The findings indicate that urban trees have
significant value-added potential, beyond their ecological benefits. The research
suggests that a diverse mix of tree species should be considered in urban tree-planting
programs to improve the resilience and sustainability of urban ecosystems. The results
of this study can help urban planners, landscape architects, and policymakers to make
informed decisions regarding the selection and management of tree species in urban
areas
Psychopathology, cultural, and school difficulties among First Nations youth
Get PDFIntroduction: Indigenous youth experience increased rates of psychopathology and school
difficulties, compared to non-Indigenous peers. Literature suggests that psychopathology is
associated with school difficulties among youth. Cultural engagement has been negatively
associated with psychopathology among Indigenous youth. The purpose of this study was to
investigate the associations between psychopathology (internalizing and externalizing
difficulties), cultural difficulties (cultural stress, lack of spirituality/religion as a strength, cultural
identity, engaging in rituals) and school difficulties (attendance, achievement, behavior) among
First Nations youth. It was hypothesized that psychopathology would be positively associated
with school difficulties.
Method: Our sample consisted of First Nations youth referred to a community-based First
Nations-led organization between February 2013 and July 2022 who completed the Child and
Adolescent Needs and Strengths Mental Health Acute (CANS-Acute) and the Child and
Adolescent Needs and Strengths Mental Health (CANS-MH).
Results: Internalizing difficulties were strongly correlated with school attendance difficulties,
while externalizing difficulties were strongly correlated with school behavior difficulties. Both
internalizing and externalizing difficulties were correlated with school achievement difficulties.
Cultural stress was significantly correlated with school attendance difficulties.
Implications: Findings from this study has improved our understanding of the relationships
between psychopathology, culture, and school difficulties among First Nations youth