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A Boron Difluoride Hydrazone (Bodihy) Polymer Exhibits Aggregation-Induced Emission, Alexander E. R. Watson, Joe Gilroy, Daniela Cappello

Chemistry Publications

Polymers that exhibit aggregation-induced emission (AIE) find use, for example, as cell-imaging agents and as fluorometric sensors due to their unique optical properties. However, the structural diversity of AIE-active polymers has not necessarily advanced at the same rate as their applications. In this work, ring-opening metathesis polymerization is used to synthesize the first example of a polymer (M_n = 61,600 g mol^‒1, Đ = 1.32) containing boron difluoride hydrazone (BODIHY) heterocycles in its repeating unit. The BODIHY monomer and polymer described absorb and emit in the visible region in solution (λ_abs = 428 and 429 nm, …

Uganda As A Role Model For Pandemic Containment In Africa, Ahmed M. Sarki, Alex Ezeh, Saverio Stranges

Epidemiology and Biostatistics Publications

No abstract provided.

The Impact Of The Diabetes Management Incentive On Diabetes-Related Services: Evidence From Ontario, Canada., Thaksha Thavam, Rose Anne Devlin, Amardeep Thind, Gregory S Zaric, Sisira Sarma

Epidemiology and Biostatistics Publications

Financial incentives have been introduced in several countries to improve diabetes management. In Ontario, the most populous province in Canada, a Diabetes Management Incentive (DMI) was introduced to family physicians practicing in patient enrollment models in 2006. This paper examines the impact of the DMI on diabetes-related services provided to individuals with diabetes in Ontario. Longitudinal health administrative data were obtained for adults diagnosed with diabetes and their family physicians. The study population consisted of two groups: DMI group (patients enrolled with a family physician exposed to DMI for 3 years), and comparison group (patients affiliated with a family physician …

Participatory Video As A Novel Recovery-Oriented Intervention In Early Psychosis: A Pilot Study., Arlene G Macdougall, Sahana Kukan, Elizabeth Price, Sarah Glen, Richelle Bird, Laura Powe, Joshua C. Wiener, Paul H Lysaker, Kelly K Anderson, Ross Mg Norman

Epidemiology and Biostatistics Publications

BACKGROUND: Personal narrative plays an important role in the process of recovery from psychotic illnesses. Participatory video is a novel, active intervention that can be used as a tool for fostering narrative development among people with psychosis.

AIM: To assess the feasibility, acceptability and potential clinical utility of participatory video as an innovative tool for promoting recovery in early psychosis.

METHODS: Ten outpatients of an early psychosis intervention programme were recruited to participate in 13 biweekly workshops to plan, film and produce documentary-style videos of their experiences. Feasibility was measured through recruitment and retention. Acceptability was measured through workshop attendance …

Cationic Boron Formazanate Dyes, Benjamin D. Katzman, Paul D. Boyle, Viktor N. Staroverov, Joe Gilroy, Ryan R. Maar

Chemistry Publications

Incorporation of cationic boron atoms into molecular frameworks is an established strategy for creating chemical species with unusual bonding and reactivity but is rarely thought of as a way of enhancing molecular optoelectronic properties. Using boron formazanate dyes as examples, we demonstrate that the wavelengths, intensities, and type of the first electronic transitions in BN heterocycles can be modulated by varying the charge, coordination number, and supporting ligands at the cationic boron atom. UV‐vis absorption spectroscopy measurements and density‐functional (DFT) calculations show that these modulations are caused by changes in the geometry and extent of π‐conjugation of the boron formazanate …

Near-Infrared Boron Difluoride Formazanate Dyes, Francis L. Buguis, Ryan R. Maar, Viktor N. Staroverov, Joe Gilroy

Chemistry Publications

Near-infrared (NIR) dyes are sought after for their utility in light harvesting, bioimaging, and light-mediated therapies. Since long-wavelength photoluminescence typically involves extensive p-conjugated systems of double bonds and aromatic rings, it is often assumed that NIR dyes have to be large molecules that require complex syntheses. We challenge this assumption by demonstrating that facile incorporation of tertiary amine groups into readily available 3-cyanoformazans affords efficient production of relatively simple NIR-active BF₂ formazanate dyes (λ_abs = 691−760 nm, λ_PL = 834−904 nm in toluene). Cyclic voltammetry experiments on these compounds reveal multiple reversible redox waves linked to the …

Stirring The Pot: Switching From Blended Fee-For-Service To Blended Capitation Models Of Physician Remuneration., Nibene H Somé, Rose Anne Devlin, Nirav Mehta, Gregory S Zaric, Sisira Sarma

Epidemiology and Biostatistics Publications

In Canada's most populous province, Ontario, family physicians may choose between the blended fee-for-service (Family Health Group [FHG]) and blended capitation (Family Health Organization [FHO] payment models). Both models incentivize physicians to provide after-hours (AH) and comprehensive care, but FHO physicians receive a capitation payment per enrolled patient adjusted for age and sex, plus a reduced fee-for-service while FHG physicians are paid by fee-for-service. We develop a theoretical model of physician labor supply with multitasking to predict their behavior under FHG and FHO, and estimable equations are derived to test the predictions empirically. Using health administrative data from 2006 to …

Delineating Heme-Mediated Versus Direct Protein Oxidation In Peroxidase-Activated Cytochrome, Victor Yin, Derek Holzscherer, Lars Konermann

Chemistry Publications

Oxidation of key residues in cytochrome c (cyt c) by chloramine T (CT) converts the protein from an electron transporter to a peroxidase. This peroxidase-activated state represents an important model system for exploring the early steps of apoptosis. CT-induced transformations include oxidation of the distal heme ligand Met80 (MetO, +16 Da) and carbonylation (LysCHO, -1 Da) in the range of Lys53/55/72/73. Remarkably, the 15 remaining Lys residues in cyt c are not susceptible to carbonylation. The cause of this unusual selectivity is unknown. Here we applied top-down mass spectrometry (MS) to examine whether CT-induced oxidation is catalyzed by heme. …

Transesterification Of Poly(Ethyl Glyoxylate): A Route To Structurally Diverse Polyglyoxylates, Rebecca E. Yardley, Amir Rabiee Kenaree, Xiaoli Liang, Elizabeth R. Gillies

Chemistry Publications

Polyglyoxylates are a class of self-immolative polymers that depolymerize in solution and the solid state. The glyoxylic acid degradation product is a metabolite in the glyoxylate cycle and can also be processed in the liver in humans, making polyglyoxylates attractive for applications in the environment and in medicine. Although expanding the scope of available polyglyoxylates would enable new properties and applications, highly pure glyoxylate monomers are required for polymerization, and this level of purity is difficult to achieve for many potential monomers. To address this challenge, we report here the 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD)-catalyzed post-polymerization transesterification of poly(ethyl glyoxylate) (PEtG) as a …

Interpretations Of Lava Flow Properties From Radar Remote Sensing Data, Gavin Douglas Tolometti, Catherine Neish, Gordon R. Osinski, Scott S. Hughes, Shannon E. Kobs-Nawotniak

Earth Sciences Publications

The surface morphology and roughness of a lava flow provides insight on its lava properties and emplacement processes. This is essential information for understanding the eruption history of lava fields, and magmatic processes beneath the surface of Earth and other planetary bodies such as the Moon. The surface morphology is influenced by lava properties such as viscosity, temperature, composition, and rate of shear. In this work, we seek to understand how we can interpret the emplacement processes and lava properties of lava flows using remote sensing data. Craters of the Moon (COTM) National Monument and Preserve in Idaho hosts a …

Call To Action: Sars-Cov-2 And Cerebrovascular Disorders (Cascade), Shahram Abootalebi, Benjamin M. Aertker, Mohammad Sobhan Andalibi, Negar Asdaghi, Ozlem Aykac, M. Reza Azarpazhooh, M. Cecilia Bahit, Kristian Barlinn, Hamidon Basri, Reza Bavarsad Shahripour, Anna Bersano, Jose Biller, Afshin Borhani-Haghighi, Robert D. Brown, Bruce Cv Campbell, Salvador Cruz-Flores, Deidre Anne De Silva, Mario Di Napoli, Afshin A. Divani, Randall C. Edgell, Johanna T. Fifi, Abdoreza Ghoreishi, Teruyuki Hirano, Keun Sik Hong, Chung Y. Hsu, Josephine F. Huang, Manabu Inoue, Amanda L. Jagolino, Moira Kapral, Hoo Fan Kee, Zafer Keser, Rakesh Khatri

Epidemiology and Biostatistics Publications

Background and purpose: The novel severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2), now named coronavirus disease 2019 (COVID-19), may change the risk of stroke through an enhanced systemic inflammatory response, hypercoagulable state, and endothelial damage in the cerebrovascular system. Moreover, due to the current pandemic, some countries have prioritized health resources towards COVID-19 management, making it more challenging to appropriately care for other potentially disabling and fatal diseases such as stroke. The aim of this study is to identify and describe changes in stroke epidemiological trends before, during, and after the COVID-19 pandemic. Methods: This is an international, multicenter, hospital-based …

Deciphering Tip-Enhanced Raman Imaging Of Carbon Nanotubes With Deep Learning Neural Networks., Usant Kajendirarajah, María Olivia Avilés, François Lagugné-Labarthet

Chemistry Publications

Recent release of open-source machine learning libraries presents opportunities to unify machine learning with nanoscale research, thus improving effectiveness of research methods and characterization protocols. This paper outlines and demonstrates the effectiveness of such a synergy with artificial neural networks to provide for an accelerated and enhanced characterization of individual carbon nanotubes deposited over a surface. Our algorithms provide a rapid diagnosis and analysis of tip-enhanced Raman spectroscopy mappings and the results show an improved spectral assignment of spectral features and spatial contrast of the collected images. Using several examples, we demonstrate the robustness and versatility of our deep learning …

Thermoresponsive Self-Immolative Polyglyoxylamides., Amir Rabiee Kenaree, Quinton E. A. Sirianni, Kyle Classen, Elizabeth R. Gillies

Chemistry Publications

Thermoresponsive polymers with lower critical solution temperatures (LCSTs) are of significant interest for a wide range of applications from sensors to drug delivery vehicles. However, the most widely investigated LCST polymers have nondegradable backbones, limiting their applications

Formation Of Gaseous Proteins Via The Ion Evaporation Model (Iem) In Electrospray Mass Spectrometry., Elnaz Aliyari, Lars Konermann

Chemistry Publications

The mechanisms whereby protein ions are released into the gas phase from charged droplets during electrospray ionization (ESI) continue to be controversial. Several pathways have been proposed. For native ESI the charged residue model (CRM) is favored; it entails the liberation of proteins via solvent evaporation to dryness. Unfolded proteins likely follow the chain ejection model (CEM), which involves the gradual expulsion of stretched-out chains from the droplet. According to the ion evaporation model (IEM) ions undergo electrostatically driven desorption from the droplet surface. The IEM is well supported for small precharged species such as Na⁺. However, it …

Risk Of New Bloodstream Infections And Mortality Among People Who Inject Drugs With Infective Endocarditis., Charlie Tan, Esfandiar Shojaei, Joshua C. Wiener, Meera Shah, Sharon Koivu, Michael Silverman

Epidemiology and Biostatistics Publications

IMPORTANCE: People who inject drugs (PWID) who are being treated for infective endocarditis remain at risk of new bloodstream infections (BSIs) due to ongoing intravenous drug use (IVDU).

OBJECTIVES: To characterize new BSIs in PWID receiving treatment for infective endocarditis, to determine the clinical factors associated with their development, and to determine whether new BSIs and treatment setting are associated with mortality.

DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study was performed at 3 tertiary care hospitals in London, Ontario, Canada, from April 1, 2007, to March 31, 2018. Participants included a consecutive sample of all PWID 18 years or …

The Impact Of Improved Access To After-Hours Primary Care On Emergency Department And Primary Care Utilization: A Systematic Review., Michael Hong, Amardeep Thind, Gregory S Zaric, Sisira Sarma

Epidemiology and Biostatistics Publications

Access to after-hours primary care is problematic in many developed countries, leading patients to instead visit the emergency department for non-urgent conditions. However, emergency department utilization for conditions treatable in primary care settings may contribute to emergency department overcrowding and increased health system costs. This systematic review examines the impact of various initiatives by developed countries to improve access to after-hours primary care on emergency department and primary care utilization. We performed a systematic review on the impact of improved access to after-hours primary and searched CINAHL, EMBASE, MEDLINE, and Scopus. We identified 20 studies that examined the impact of …

Analysis Of Temperature-Dependent H/D Exchange Mass Spectrometry Experiments., Nastaran N Tajoddin, Lars Konermann

Chemistry Publications

H/D exchange (HDX) mass spectrometry (MS) is a widely used technique for interrogating protein structure and dynamics. Backbone HDX is mediated by opening/closing (unfolding/refolding) fluctuations. In traditional HDX-MS, proteins are incubated in D₂O as a function of time at constant temperature (T). There is an urgent need to complement this traditional approach with experiments that probe proteins in a T-dependent fashion, e.g., for assessing the stability of therapeutic antibodies. A key problem with such studies is the absence of strategies for interpreting HDX-MS data in the context of T-dependent protein dynamics. Specifically, it has …

Phosphonium Versus Ammonium Compact Polyelectrolyte Complex Networks With Alginate-Comparing Their Properties And Cargo Encapsulation., Tristan D. Harrison, Alexandre J. Salmon, John R. De Bruyn, Paul J. Ragogna, Elizabeth R. Gillies

Chemistry Publications

Phosphonium and ammonium polymers can be combined with polyanions to form polyelectrolyte complex (PEC) networks, with potential application in self-healing materials and drug delivery vehicles. While various structures and compositions have been explored, to the best of our knowledge, analogous ammonium and phosphonium networks have not been directly compared to evaluate the effects of phosphorus versus nitrogen cations on the network properties. In this study, we prepared PECs from sodium alginate and poly[triethyl(4-vinylbenzyl)phosphonium chloride], poly[triethyl(4-vinylbenzyl)ammonium chloride], poly[tri(

Benzosiloles With Crystallization-Induced Emission Enhancement Of Electrochemiluminescence: Synthesis, Electrochemistry, And Crystallography, Liuqing Yang, Donghyun Koo, Jackie Wu, Jonathan M. Wong, Tyler Day, Ruizhong Zhang, Harshana Kolongoda, Kehan Liu, Jian Wang, Zhifeng Ding, Brian Pagenkopf

Chemistry Publications

Crystallization-induced emission enhancement (CIEE) was demonstrated for the first time for electrochemilunimescence (ECL) with two new benzosiloles. Compared with their solution, the films of the two benzosiloles gave CIEE of 24 times and 16 times. The mechanism of the CIEE-ECL was examined by spooling ECL spectroscopy, X-ray crystal structure analysis, photoluminescence, and DFT calculation. This CIEE-ECL system is a complement to the well-established aggregation-induced emission enhancement (AIEE) systems. Unique intermolecular interactions are noted in the crystalline chromophore. The first heterogeneous ECL system is established for organic compounds with highly hydrophobic properties.

Excess Mortality From Covid-19: A Commentary On The Italian Experience, Paolo Pasquariello, Saverio Stranges

Epidemiology and Biostatistics Publications

No abstract provided.

Gas Phase Protein Folding Triggered By Proton Stripping Generates Inside-Out Structures: A Molecular Dynamics Simulation Study., Alexander I M Sever, Lars Konermann

Chemistry Publications

The properties of electrosprayed protein ions continue to be enigmatic, owing to the absence of high-resolution structure determination methods in the gas phase. There is considerable evidence that under properly optimized conditions these ions preserve solution-like conformations and interactions. However, it is unlikely that these solution-like conformers represent the "intrinsic" structural preferences of gaseous proteins. In an effort to uncover what such intrinsically preferred conformers might look like, we performed molecular dynamics (MD) simulations of gaseous ubiquitin. Our work was inspired by recent gas phase experiments, where highly extended 13+ ubiquitin ions were transformed to compact 3+ species by proton …

Age At Migration And The Risk Of Psychotic Disorders: A Systematic Review And Meta-Analysis., Kelly K. Anderson, Jordan Edwards

Epidemiology and Biostatistics Publications

OBJECTIVE: To conduct a systematic review and meta-analysis of the existing evidence on the association between age at migration and the risk of psychotic disorders.

METHODS: Observational studies were eligible for inclusion if they presented data on the association between age at migration and the risk of psychotic disorders among first-generation migrant groups. We used two random effects meta-analyses to pool effect estimates for each stratum of age at migration relative to (i) a native-born reference category and (ii) the youngest age stratum (0 to 2 years).

RESULTS: Ten studies met inclusion criteria, and five were included in the meta-analysis. …

What Malaysian Software Students Think About Testing?, Luiz Fernando Capretz, Shuib Basri, Maythem Adili, Aamir Amin

Electrical and Computer Engineering Publications

Software testing is one of the crucial supporting processes of software life cycle. Unfortunately for the software industry, the role is stigmatized, partly due to misperception and partly due to treatment of the role in the software industry. The present study aims to analyse this situation to explore what inhibit an individual from taking up a software testing career. In order to investigate this issue, we surveyed 82 senior students taking a degree in information technology, information and communication technology, and computer science at two Malaysian universities. The subjects were asked the PROs and CONs of taking up a career …

Rdc Data Alternatives: Conducting Research During Covid-19, Kristi Thompson, Elizabeth Hill

Western Libraries Presentations

Recent physical distancing protocols pertaining to the COVID-19 Pandemic have meant that RDC researchers need to find alternatives ways of carrying out their research. The Real Time Remote Access (RTRA) program offers one alternative way to access confidential Statistics Canada data. Other options include using the Statistics Canada public use files and analyzing data from other sources.

The presenters, data librarians from Western Libraries will discuss the differences between the data that can be accessed through the RTRA the RDC. RTRA data is a very useful option for some types of questions but also has some important limitations. We will …

Hierarchical Plasmon Resonances In Fractal Structures, Isobel C. Bicket, Edson P. Bellido, Danielle M. Mcrae, Francois Lagugne-Labarthet, Gianluigi A. Botton

Chemistry Publications

An equilateral triangular prism is used as the fundamental building block to con- struct additive Sierpinski fractals, enabling new surface plasmon resonances (SPR) in the first three generations of Sierpinski triangles, as well as topological intermediaries between generations. The modes are characterized using electron energy loss spectroscopy accompanied by eigenmode calculations and optical finite-difference time domain simulations. The complex fractal geometries present a predictable hierarchy of new resonances, each arising from the previous generational building blocks used to construct the fractal. Intermediate structures break the polarization degeneracy of the equilateral fractals while maintaining a rich multiband spectral response. Engineering defects …

Concordance Between Health Administrative Data And Survey-Derived Diagnoses For Mood And Anxiety Disorders, J. Edwards, A. Thind, S. Stranges, M. Chiu, Kelly K. Anderson

Epidemiology and Biostatistics Publications

Objective: To assess whether estimates of survey structured interview diagnoses of mood and anxiety disorders were concordant with diagnoses of these disorders obtained from health administrative data.

Methods: All Ontario respondents to the 2012 Canadian Community Health Survey-Mental Health (CCHS-MH) were linked to health administrative databases at ICES (formerly known as the Institute for Clinical Evaluative Sciences). Survey structured interview diagnoses were compared with health administrative data diagnoses obtained using a standardized algorithm. We used modified Poisson regression analyses to assess whether socio-demographic factors were associated with concordance between the two measures.

Results: Of the 4157 Ontarians included in our …

Optoelectronic Properties Of Carbon-Bound Boron Difluoride Hydrazone Dimers, Daniela Cappello, Ryan R. Maar, Viktor N. Staroverov, Joe Gilroy

Chemistry Publications

The creation of dimeric boron difluoride complexes of chelating N-donor ligands is a proven strategy for the enhancement of the optoelectronic properties of fluorescent dyes. We report dimers based on the boron difluoride hydrazone (BODIHY) framework, which offer unique and sometimes unexpected substituent-dependent absorption, emission, and electrochemical properties. BODIHY dimers have low-energy absorption bands (l_max = 421 to 479 nm, e = 17,200 to 39,900 M⁻¹ cm⁻¹) that are red-shifted relative to monomeric analogues. THF solutions of these dimers exhibit aggregation-induced emission upon addition of water, with emission enhancement factors ranging from 5 to 18. …

Discovery Of A Remarkably Powerful Broad Absorption-Line Quasar Outflow In Sdss J135246.37+423923.5, Hyunseop Choi, Karen M. Leighly, Donald M. Terndrup, Sarah C. Gallagher, Gordon T. Richards

Physics and Astronomy Publications

Broad absorption-line (BAL) features in quasar spectra reveal an unambiguous signature of energetic outflows from central supermassive black holes, and thus, BAL quasars are prime targets for investigating the potential process of luminous quasar feedback on galaxies. We analyzed the rest-UV spectrum of an "overlapping trough" iron low-ionization broad absorption-line quasar (FeLoBAL) SDSS J135246.37+423923.5 using the novel spectral synthesis code SimBAL and discovered an extraordinarily fast and energetic BAL outflow. Our analysis revealed outflow velocities reaching ∼ -38,000 km s-1 with a velocity width of ∼ 10,000 km s-1, which is the largest FeLoBAL outflow velocity measured to date. The …

Northern Tornadoes Project 2018/19 Report, Northern Tornadoes Project

Project Reports

Three years ago, we set our sights on finding at least a few undocumented tornado tracks in the remote forests of northern Ontario.

We have covered greater distances and nurtured bigger ambitions since then.

From northern Ontario to all of Canada, from aircraft surveys to drones and satellites, from on-the- ground damage investigations to artificial intelligence analyses, the Northern Tornadoes Project is one of the most comprehensive tornado research projects in the country. It aims to better detect tornado occurrences throughout Canada, improve communication of tornado science and risk, and mitigate against harm to people and property. NTP also seeks …

Redox Polymers Incorporating Pendant 6-Oxoverdazyl And Nitronyl Nitroxide Radicals, Michael Anghel, Francois Magnan, Sara D. Catingan, Matthew A. Mccready, Elaheh Aawani, Victor Wong, Deepa Singh, Giovanni Fanchini, Joe Gilroy

Chemistry Publications

Polymers comprised of redox-active organic radicals have emerged as promising materials for use in a variety of organic electronics, including fast-charging batteries. Despite these advances, relatively little attention has been focused on the diversification of the families of radicals that are commonly incorporated into polymer frameworks, with most radical polymers being comprised of nitroxide radicals. Here, we report two new examples prepared via ring-opening methathesis polymerization containing 6-oxoverdazyl and nitronyl nitroxide radicals appended to their backbones. The polymerization reaction and optoelectronic properties were explored in detail, revealing high radical content and redox activity that may be advantageous for their use …