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Exploring the Structural, Magnetic, Optical, and Catalytic Properties of High-Spin Materials
Full text linkThis thesis explores the design, synthesis, and characterization of lanthanide-based
coordination frameworks (MOFs) and heterometallic 3d/4f complexes, with a focus on tunable
magnetic behavior, photophysical properties, and catalytic performance. Four complementary
research directions were pursued, each addressing key challenges in molecular magnetism,
luminescence and sustainable catalysis. The first project examines a family of isomorphous Dy(III),
Gd(III), and Tb(III)-MOFs constructed from 2',5'-bis(methoxymethyl)-[1,1':4',1''-terphenyl]-4,4''
dicarboxylic acid (H2L2.1). Systematic post-synthetic solvent exchange led to tunable structural
perturbations that profoundly affected the magnetic relaxation dynamics and photophysical
behavior of the Dy-MOF. Alternating current (ac) magnetic studies of the Dy-MOF series revealed
distinct relaxation pathways linked to subtle crystallographic changes. A second ligand, 2',5'
bis(ethoxymethyl)-[1,1':4',1''-terphenyl]-4,4''-dicarboxylic acid (H2L2.2), demonstrated how minimal
chemical modifications to the linker can afford new MOFs with conserved coordination geometries
and consistent magnetic and luminescent properties across the lanthanide series. These results
underscore the sensitivity of magnetic relaxation and energy transfer processes to both the
framework structure and local symmetry. In the second project, three novel, isostructural Dy-, Gd-
and Tb-MOFs were synthesized from 4,4′-(1,2,4,5-tetrazine-3,6-diyl)dibenzoic acid (H₂TZDC). ac
magnetic studies revealed the MOFs exhibit complex temperature-dependent slow magnetic
relaxation, attributed to combined quantum tunneling (QTM), Orbach, and Raman mechanisms.
Notably, the Gd-based system displays rare frequency-dependent relaxation, rationalized by a small
axial anisotropy in the crystal field. Photoluminescence studies on this series of MOFs reveal
inefficient ligand-to-metal energy transfer, attributed to mismatched electronic energies. In the third
study a series of tetranuclear {Cu₄Ln₄} clusters assembled from the rac-mpzmH ligand are reported.
Magnetostructural studies reveal that weak Cu–Ln antiferromagnetic coupling, strong Cu–Cu
ferromagnetic interactions, and variations in the coordination geometries collectively govern the
magnetic behaviour. Field-induced slow relaxation was observed in the {Cu4Dy4} cluster, while the Tb
and Er analogues exhibited active QTM, effectively suppressing relaxation over the energy barrier
even in the presence of an external magnetic field. The photoluminescence was largely quenched by
the Cu(II) centers, although trace Ln-centered emission was observed in the {Cu4Tb4} cluster. These
results highlight the interplay between nuclearity, bridging geometry, and electronic structure in
determining the magnetic and optical properties. Project 4 focuses on heterometallic 3d/4f
complexes of the form [TM₂Ln(TX-TACN)]⁺ (TM(II) = Cu and Zn; Ln(III) = Gd, Dy, Tb, Eu and Ho); and TX
TACNH3 = N,N′,N″-tris(3,5-dimethyl-2-hydroxybenzyl)-1,4,7-triazacyclononane) as catalysts for the
cycloaddition of CO₂ with epoxides. X-ray diffraction studies revealed that all the complexes
comprise of a linear TM–Ln–TM motif with a subtle variation in the coordination geometry dependent
upon the 3d ion. Catalytic studies showed that the Zn(II)-based complexes significantly outperform
their Cu(II) counterparts, achieving high turnover numbers and frequencies for propylene oxide
conversion. Selectivity studies using cyclohexene oxide demonstrate stereochemical control and
unique reactivity pathways. The catalytic performance varies with the 4f metal and counterion,
demonstrating the modularity and adaptability of these systems for green chemistry applications
El Poema del Niagara, 1880
Full text linkJuan Antonio Pérez Bonalde (1846-1892) was a Venezuelan poet and translator. He was born in Caracas, Venezuela, but spent much of his life in exile as a result of political problems between his family and the Venezuelan government. His literary works include Estrofas; Ritmos; Poema del Niagara; Vuelta a la Patria; and Flor. He also translated the work of other poets into Spanish, most notably Edgar Allan Poe’s The Raven and The Songbook by Heine. He is buried in the National Pantheon of Venezuela.
Emilio Castelar (1832-1899) was a Spanish politician, historian and journalist. He was President of the Executive Power of the First Spanish Republic between 1873 and 1874.A manuscript poem about Niagara written in Spanish by Juan Antonio Pérez-Bonalde titled El Poema del Niagara. The poem is handwritten and dedicated to Emilio Castelar, a Spanish politician, historian, and journalist. The notebook contains 64 pages and is bound in leather with gold lettering on the cover that reads “A Emilio Castelar. El Poema del Niagara por J.A. Perez Bonalde, New York”. The translated dedication reads “The Poem of Niagara. To the Tribune of Liberty, Friend of America, To the glorious son of noble Spain, from that generous, poetic, and chivalrous land that I love so much, And in which I wish to see the end of my days, wrapped in the flag of gold and gravel under whose folds my ancestors were born to light, honor, and freedom. To His Excellency Mr. Emilio Castelar, This humble song, in homage of sincere, ardent, and profound admiration Dedicates The Author New York, July 15, 1880.” The last page is signed by J.A. Perez Bonalde, and dated “Niagara Falls, Clifton (Canada), July 4, 1880.” At the bottom of this same page is written “Liberty Street, New York, July 15, 1880”.
The poem is structured into nine sections, which are: (I) The Lyre and the Harp; (II) The River; (III) The Torrent; (IV) Sub-Umbra; (V) The Echo; (VI) Hosanna!; (VII) Man and Abyss; (VIII) La Poesia; and (IX) Dies Grae. This manuscript contains some additional lines not found in some of the published versions
MINDFULNESS AND NON-ARISTOTELIANISM LOGIC AS META-PRACTISES for TEACHER EDUCATION: A PHILOSOPHICAL APPROACH TO MATURE THE SUBFIELD
No full textSingle Paper in Multi-Paper Session for 2025 CSSE Conference
"Mindful Inclusion in Teacher Education" for the Canadian Association for Teacher Education (CATE-ACFE). Toronto, ON, Canada.Some are born to teach, and we categorise such inclinations in the realm of the ‘innate.’ Others fall upon teaching by necessity, or a disciplined and professional approach to make a living wage; such is the realm of the ‘learned.’ When my mother bumped into my teacher in the grocery store, she shared that I was pursuing a PhD. “OH I just knew he would! Knew all along” came the response. The lady my mother bumped into was my senior kindergarten teacher. My academic question became: what is the relationship between the innate and the learned? The purpose of the study is to conduct a conceptual analysis to bring new meanings, new symbols, and new worldviews to potentiate teachers-in-development of their craft through meta-practices—namely mindfulness and non-Aristotelian logic. My rationale is to take up the challenge of Jonathan Neufeld in locating and systematising these referenced but undefined meta-practices by continuing the Waller-Jackson-Lortie-Neufeld (WJLN) lineage. These practices are “sorely needed” as we enter into an integral (post-postmodern) or post-humanist worldview that becomes integrative rather than selective, integral rather than empirical, intuitive and rational, rather than rational alone, and spiritual and material rather than material alone.Non
The Weak Spot: Psychopathic Traits and Environmental Cues for Exploitation
Full text linkThe social predator hypothesis claims that people with psychopathic traits are capable of and often do engage in the exploitation of others for their own benefit. For people with psychopathic traits to be successful in this regard, they need to be able to judge the vulnerability of those they aim to exploit. Research has established that people with psychopathic traits are better able to detect behavioural cues of vulnerability (e.g. gait) that are related to previous victimization, but the current study examines how they might also use environmental cues to determine potential for exploitation. In this study, male participants (n = 118) engaged in an imagined victimization task where they watched video stimuli and verbally commented on features of the environment (e.g., lighting) and people (e.g., gender) that influenced their decisions about who to exploit. A
thematic analysis found the following relevant themes when analyzing commentary provided by participants high vs. low in psychopathy: a) centering the self as the imagined perpetrator; b) motivation to assess vulnerability to victimization. Overall, it was found that psychopathic traits were positively associated with using person-based cues and negatively associated with using environment-based cues when making judgements related to exploitation. Men with psychopathic traits seem to focus more on person-based features rather than environment-based features when considering vulnerability and their decisions about who to target for exploitation
Has Implementation Science found a place in the environmental domain? A review of the academic literature
Full text linkIn 2018, an article was published by Janet G. Hering that served as a call to action for the development of an implementation science for the environmental domain. This study undertakes a review of the academic literature to explore how implementation science is being discussed in the environmental domain, and if the call to action made by Hering in 2018 has been taken up by academic scholars. Key findings include: (1) implementation science is being applied in a meaningful way within the environmental domain, (2) the number of articles published in recent years shows that there may be growing interest in using implementation science within the environmental domain, and (3) the volume of mapping exercises to explore the use of implementation science within the environmental domain shows that researcher are responding to Hering (2018). Future opportunities for research and practice include building on the research that is already being undertaken by applying the findings to empirical work to understand how they work and develop lessons learned that could continue to build out implementation science within the environmental domain
Quantifying Upper Extremity Vibration Exposures During Arborist Tree Abatement Tasks
Full text linkThe purpose of this thesis was to examine chainsaw vibration exposures during various tree cutting tasks. Participants consisted of 18, healthy, male active arborists, with an Ontario Chainsaw Certification. Vibration was measured using two accelerometers, one placed on the hand and another on the tool to determine exposures during four different chainsaw cutting tasks (bore cut, down cut, up cut, idle and hold). To better understand chainsaw physical demands, surface electromyography was recorded bilaterally from six forearm muscles and whole-body kinematics were assessed using an inertial measurement system. Additionally, resting tremor, pain and discomfort, manual dexterity, and grip strength were assessed to determine performance effects from exposures. During all cutting tasks, vibration exposures from both the saw and hand exceeded recommended industry threshold limits (Bore saw: 9.62±4.10 m/s2; Bore hand: 8.72±5.02 m/s2; Down saw: 9.29±3.82 m/s2; Down hand: 9.87±6.60 m/s2; Up saw: 9.30±3.14 m/s2; Up hand: 7.47±3.03 m/s2; Idle saw: 5.96±1.25 m/s2; Idle hand: 5.65±1.09 m/s2). Resting tremor and pain and discomfort became increased after exposures as well, indicating chainsaw vibrations during cutting tasks as a risk factor in this working population
Performance Assessment of Bayesian Networks for Soil Moisture Prediction in Agricultural Water Management
Full text linkEstimating soil moisture using easily measurable parameters can significantly improve irrigation management efficiency while reducing time and cost. This study evaluated the performance of LASSO, Decision Tree, and Random Forest models for predicting soil moisture. In addition, Bayesian networks were used to model the complex interactions between soil, weather, and topographical factors at the Schäfertal site in Germany. To achieve this, seven structure learning algorithms, including PC, Grow-Shrink, Incremental Association, Fast Incremental Association, Hill Climbing, Max-Min Hill-Climbing, and Tabu Search, were used. Subsequently, soil moisture was predicted using all these algorithms to determine the best performance among them. The results showed that Bayesian networks had the best
performance for prediction, while LASSO, Decision Tree and Random Forest did not perform as well, likely due to the complex relationships between variables. Bayesian networks, however, effectively identified key factors like soil texture, depth, and evapotranspiration using measured variables across all search algorithms. Bayesian networks showed better performance than the other three models. More importantly, they predicted soil moisture using only a subset of variables, with performance close to that achieved using the full set of variables. This result demonstrates improvements in predictions and handling missing data in practical applications such as precision agriculture and water managemen
Exploring associations between cannabis prices, stores, and usage after recreational legalization
Full text linkAvailable online ahead of print. The article is not officially "open access" but the publisher has made it open access for the time being. The publisher apparently allows accepted manuscripts to be posted on institutional repositories without embargo.Introduction: Canada legalized recreational cannabis in October 2018, but commercial retailing took time to develop. This study first explored how self-reported cannabis use prevalence, daily use, product type use, and age of initial use changed during 2019–2023. It then analyzed whether the changes were associated with rising store numbers or falling prices.
Methods: Data on store counts, retail pricing, and cannabis use came from government reports covering 10 provinces over 5 years. Panel data linear regressions analyzed 50 province-year aggregated observations.
Results: There were no significant changes in prevalence among males and people aged 16–24 or in the proportion using cannabis daily. Prevalence among females and people aged 25+ increased; those levels showed negative associations with prices but not stores. Dried cannabis use decreased, while edibles use increased; those also showed associations with prices but not stores. Mean initial age of use increased; it was negatively associated with prices and positively with stores.
Conclusion: Canada’s large cannabis retail expansion was accompanied by relatively modest usage changes, most of which showed associations with falling prices but not rising store counts
Norman Ball Stereo Card Collection, 1873-1905, n.d.
Full text linkNorman R. Ball is the owner and founder of Norman R. Ball and Associates. The focus of the company is the history of technology and engineering and the interaction between technology and society. Dr. Ball was formerly the Director for Society, Technology and Values at the University of Waterloo. He also served as the Director of the Centre of Society Technology and Values and Northern Telecom. He was a Professor of Engineering Impact on Society in the Department of Systems Design Engineering at the University of Alberta. His research has covered a wide variety of topics including: hospitals, the history of engineering in Canada, Canadian public works, electrical manufacturing and Niagara Falls tourism. He received his PhD in Philosophy at the University of Toronto.The collection consists of 104 stereo cards of Niagara Falls and the Niagara River sorted by publisher or photographer. Photographers and publishers include American Scenery; E. & H.T. Anthony, including “American Views”; Geo. Barker, photographer, Niagara Falls, New York; C. Bierstadt; Geo. E. Curtis; Griffith & Griffith; T. W. Ingersoll; International Stereoscopic View Co.; Keystone View Company; B.W. Kilburn; The “Perfec” Stereograph / H.C. White; Standard Series, American scenery; Strohmeyer & Wyman, sold by Underwood and Underwood; and Underwood and Underwood
Teacher Stress and Coping: A Handbook for Ghanaian Teachers
Full text linkTeacher stress is persistent, and has become a growing concern in educational systems globally – with Ghana being no exception. This research addresses the critical issue of teacher stress by developing a practical and context-specific handbook aimed at supporting teachers in identifying stressors and adopting effective coping strategies. Drawing on the Transactional Model of Stress and Coping (Lazarus & Folkman, 1987) and Carver’s (1997) Brief-COPE, the handbook integrates theoretical insights with real-world applicability. The study reviews existing literature on teacher well-being, highlighting key stressors such as workload and role demands, interpersonal relationships, institutional and policy contexts, and professional identity and career development contexts. The handbook provides an Appraisal Guide for self-assessment, and includes content on both adaptive and maladaptive coping strategies. It is designed as both a reflective and practical resource for teachers, school leaders, and policymakers, with the aim of promoting teacher well-being and resilience. It further examines coping strategies commonly employed by teachers, particularly those relevant to the Ghanaian context including active coping, religious coping, and seeking emotional and instrumental support (Masko & Bosiwah, 2016). The project concludes that providing accessible tools for stress appraisal and coping can empower teachers, enhance job satisfaction, and contribute to a healthier educational environment. Future research is recommended to validate the appraisal tool and explore broader applications of the handbook across diverse educational settings specific to Ghana