29,160 results on '"Paquette A"'
Search Results
252. Twistorial monopoles & chiral algebras
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Niklas Garner and Natalie M. Paquette
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Nonperturbative Effects ,Supersymmetric Gauge Theory ,Scattering Amplitudes ,Wilson, ’t Hooft and Polyakov loops ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
Abstract We initiate the study of how the insertion of magnetically charged states in 4d self-dual gauge theories impacts the 2d chiral algebras supported on the celestial sphere at asymptotic null infinity, from the point of view of the 4d/2d twistorial correspondence introduced by Costello and the second author. By reducing the 6d twistorial theory to a 3d holomorphic-topological theory with suitable boundary conditions, we can motivate certain non-perturbative enhancements of the celestial chiral algebra corresponding to extensions by modules arising from 3d boundary monopole operators. We also identify the insertion of 4d (non-abelian) monopoles with families of spectral flow automorphisms of the celestial chiral algebra.
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- 2023
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253. Sourcing high tissue quality brains from deceased wild primates with known socio‐ecology
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Tobias Gräßle, Catherine Crockford, Cornelius Eichner, Cédric Girard‐Buttoz, Carsten Jäger, Evgeniya Kirilina, Ilona Lipp, Ariane Düx, Luke Edwards, Anna Jauch, Kathrin S. Kopp, Michael Paquette, Kerrin Pine, EBC Consortium, Daniel B. M. Haun, Richard McElreath, Alfred Anwander, Philipp Gunz, Markus Morawski, Angela D. Friederici, Nikolaus Weiskopf, Fabian H. Leendertz, and Roman M. Wittig
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brain connectivity ,brain evolution ,brain extraction ,brain microstructure ,field necropsy ,MRI ,Ecology ,QH540-549.5 ,Evolution ,QH359-425 - Abstract
Abstract The selection pressures that drove dramatic encephalisation processes through the mammal lineage remain elusive, as does knowledge of brain structure reorganisation through this process. In particular, considerable structural brain changes are present across the primate lineage, culminating in the complex human brain that allows for unique behaviours such as language and sophisticated tool use. To understand this evolution, a diverse sample set of humans' closest relatives with varying socio‐ecologies is needed. However, current brain banks predominantly curate brains from primates that died in zoological gardens. We try to address this gap by establishing a field pipeline mitigating the challenges associated with brain extractions of wild primates in their natural habitat. The success of our approach is demonstrated by our ability to acquire a novel brain sample of deceased primates with highly variable socio‐ecological exposure and a particular focus on wild chimpanzees. Methods in acquiring brain tissue from wild settings are comprehensively explained, highlighting the feasibility of conducting brain extraction procedures under strict biosafety measures by trained veterinarians in field sites. Brains are assessed at a fine‐structural level via high‐resolution MRI and state‐of‐the‐art histology. Analyses confirm that excellent tissue quality of primate brains sourced in the field can be achieved with a comparable tissue quality of brains acquired from zoo‐living primates. Our field methods are noninvasive, here defined as not harming living animals, and may be applied to other mammal systems than primates. In sum, the field protocol and methodological pipeline validated here pose a major advance for assessing the influence of socio‐ecology on medium to large mammal brains, at both macro‐ and microstructural levels as well as aiding with the functional annotation of brain regions and neuronal pathways via specific behaviour assessments.
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- 2023
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254. Aero‐servo‐elastic co‐optimization of large wind turbine blades with distributed aerodynamic control devices
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Nikhar J. Abbas, Pietro Bortolotti, Christopher Kelley, Joshua Paquette, Lucy Pao, and Nick Johnson
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control co‐design ,control systems ,distributed aerodynamic control ,multidisciplinary design ,optimization ,Renewable energy sources ,TJ807-830 - Abstract
Abstract This work introduces automated wind turbine optimization techniques based on full aero‐servo‐elastic models and investigates the potential of trailing edge flaps to reduce the levelized cost of energy (LCOE) of wind turbines. The Wind Energy with Integrated Servo‐control (WEIS) framework is improved to conduct the presented research. Novel methods for the generic implementation and tuning of trailing edge flap devices and their controller are also introduced. Primary flap and controller parameters are optimized to demonstrate potential maximum blade tip deflection reductions of 21%. Concurrent design optimization (i.e., co‐design) of a novel segmented wind turbine blade with trailing edge flaps and its controller is then conducted to demonstrate blade cost savings of 5%. Additionally, rotor diameter co‐design optimization is demonstrated to reduce the LCOE by 1.3% without significant load increases to the tower. These results demonstrate the efficacy of control co‐design optimization using trailing edge flaps, and the entirety of this work provides a foundation for numerous control co‐design‐oriented studies for distributed aerodynamic control devices.
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- 2023
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255. Understanding the impacts of the COVID-19 pandemic on the care experiences of people with mental-physical multimorbidity: protocol for a mixed methods study
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Matthew Menear, Arnaud Duhoux, Myreille Bédard, Jean-Sébastien Paquette, Marie Baron, Mylaine Breton, Simon Courtemanche, Savannah Dubé, Stefany Dufour, Martin Fortin, Ariane Girard, Émilie Larouche-Côté, Audrey L’Espérance, Annie LeBlanc, Marie-Eve Poitras, Sophie Rivet, Maxime Sasseville, Amélie Achim, Patrick Archambault, Virtue Bajurny, Judith Belle Brown, Jean-Daniel Carrier, Nancy Côté, Yves Couturier, Maman Joyce Dogba, Marie-Pierre Gagnon, Sergio Cortez Ghio, Emily Gard Marshall, Anita Kothari, Marie-Thérèse Lussier, Frances S. Mair, Susan Smith, Brigitte Vachon, and Sabrina Wong
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Primary care ,Mental health ,Multimorbidity ,Chronic disease ,COVID-19 ,Health care experiences ,Medicine (General) ,R5-920 - Abstract
Abstract Background Primary care and other health services have been disrupted during the COVID-19 pandemic, yet the consequences of these service disruptions on patients’ care experiences remain largely unstudied. People with mental-physical multimorbidity are vulnerable to the effects of the pandemic, and to sudden service disruptions. It is thus essential to better understand how their care experiences have been impacted by the current pandemic. This study aims to improve understanding of the care experiences of people with mental-physical multimorbidity during the pandemic and identify strategies to enhance these experiences. Methods We will conduct a mixed-methods study with multi-phase approach involving four distinct phases. Phase 1 will be a qualitative descriptive study in which we interview individuals with mental-physical multimorbidity and health professionals in order to explore the impacts of the pandemic on care experiences, as well as their perspectives on how care can be improved. The results of this phase will inform the design of study phases 2 and 3. Phase 2 will involve journey mapping exercises with a sub-group of participants with mental-physical multimorbidity to visually map out their care interactions and experiences over time and the critical moments that shaped their experiences. Phase 3 will involve an online, cross-sectional survey of care experiences administered to a larger group of people with mental disorders and/or chronic physical conditions. In phase 4, deliberative dialogues will be held with key partners to discuss and plan strategies for improving the delivery of care to people with mental-physical multimorbidity. Pre-dialogue workshops will enable us to synthesize an prepare the results from the previous three study phases. Discussion Our study results will generate much needed evidence of the positive and negative impacts of the COVID-19 pandemic on the care experiences of people with mental-physical multimorbidity and shed light on strategies that could improve care quality and experiences.
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- 2023
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256. Grand challenges in the design, manufacture, and operation of future wind turbine systems
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P. Veers, C. L. Bottasso, L. Manuel, J. Naughton, L. Pao, J. Paquette, A. Robertson, M. Robinson, S. Ananthan, T. Barlas, A. Bianchini, H. Bredmose, S. G. Horcas, J. Keller, H. A. Madsen, J. Manwell, P. Moriarty, S. Nolet, and J. Rinker
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Renewable energy sources ,TJ807-830 - Abstract
Wind energy is foundational for achieving 100 % renewable electricity production, and significant innovation is required as the grid expands and accommodates hybrid plant systems, energy-intensive products such as fuels, and a transitioning transportation sector. The sizable investments required for wind power plant development and integration make the financial and operational risks of change very high in all applications but especially offshore. Dependence on a high level of modeling and simulation accuracy to mitigate risk and ensure operational performance is essential. Therefore, the modeling chain from the large-scale inflow down to the material microstructure, and all the steps in between, needs to predict how the wind turbine system will respond and perform to allow innovative solutions to enter commercial application. Critical unknowns in the design, manufacturing, and operability of future turbine and plant systems are articulated, and recommendations for research action are laid out. This article focuses on the many unknowns that affect the ability to push the frontiers in the design of turbine and plant systems. Modern turbine rotors operate through the entire atmospheric boundary layer, outside the bounds of historic design assumptions, which requires reassessing design processes and approaches. Traditional aerodynamics and aeroelastic modeling approaches are pressing against the limits of applicability for the size and flexibility of future architectures and flow physics fundamentals. Offshore wind turbines have additional motion and hydrodynamic load drivers that are formidable modeling challenges. Uncertainty in turbine wakes complicates structural loading and energy production estimates, both around a single plant and for downstream plants, which requires innovation in plant operations and flow control to achieve full energy capture and load alleviation potential. Opportunities in co-design can bring controls upstream into design optimization if captured in design-level models of the physical phenomena. It is a research challenge to integrate improved materials into the manufacture of ever-larger components while maintaining quality and reducing cost. High-performance computing used in high-fidelity, physics-resolving simulations offer opportunities to improve design tools through artificial intelligence and machine learning, but even the high-fidelity tools are yet to be fully validated. Finally, key actions needed to continue the progress of wind energy technology toward even lower cost and greater functionality are recommended.
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- 2023
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257. Landscape influence on permafrost ground ice geochemistry in a polar desert environment, Resolute Bay, Nunavut
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Michel Paquette, Melissa J. Lafrenière, and Scott F. Lamoureux
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ground ice ,permafrost ,polar desert ,geochemistry ,geomorphology ,glace de sol ,Environmental sciences ,GE1-350 ,Environmental engineering ,TA170-171 - Abstract
Arctic permafrost is degrading and is thus releasing nutrients, solutes, sediment and water into soils and freshwater ecosystems. The impacts of this degradation depends on the geochemical characteristics and in large part on the spatial distribution of ground ice and solutes, which is not well-known in the High Arctic polar desert ecosystems. This research links ground ice and solute concentrations, to establish a framework for identifying locations vulnerable to permafrost degradation. It builds on landscape classifications and cryostratigraphic interpretations of permafrost history. Well-vegetated wetland sites with syngenetic permafrost aggradation show a different geochemical signature from polar desert and epigenetic sites. In wetlands, where ground ice contents were high (
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- 2023
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258. The Contingencies of an Academic Field
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Paquette, Jonathan, primary and Bérubé, Julie, additional
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- 2023
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259. Life-course socioeconomic status and obesity: a scoping review protocol
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Alexandre Lebel, Habila Adamou, Dener François, and Marie-Claude Paquette
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Medicine - Abstract
Objective We aim to explore the literature that studies the links between life-course socioeconomic status and weight status and characterize the life-course approach used.Introduction Obesogenic environments are increasing rapidly in deprived environments, and cross-sectional studies have shown limitations in explaining the links between these environments and obesity. The life-course approach has been proposed recently to better understand the links between socioeconomic status and weight status.Inclusion criteria Studies that identify life-course socioeconomic status and longitudinal built environment indicators and associate them with body weight indicators between January 2000 and January 2023.Methods Studies in French or English were searched in Medline (PubMed), Web of Science and GeoBase (Embase) according to the strategies formulated for each database. The selected studies were exported to Covidence for evaluation according to the inclusion/exclusion criteria.Results The main results retained are the association between longitudinal socioeconomic indicators and weight measures; longitudinal built environment indicators and the measures of weight.
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- 2024
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260. Adapting and Evaluating an AI-Based Chatbot Through Patient and Stakeholder Engagement to Provide Information for Different Health Conditions: Master Protocol for an Adaptive Platform Trial (the MARVIN Chatbots Study)
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Yuanchao Ma, Sofiane Achiche, Marie-Pascale Pomey, Jesseca Paquette, Nesrine Adjtoutah, Serge Vicente, Kim Engler, Moustafa Laymouna, David Lessard, Benoît Lemire, Jamil Asselah, Rachel Therrien, Esli Osmanlliu, Ma'n H Zawati, Yann Joly, and Bertrand Lebouché
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Medicine ,Computer applications to medicine. Medical informatics ,R858-859.7 - Abstract
BackgroundArtificial intelligence (AI)–based chatbots could help address some of the challenges patients face in acquiring information essential to their self-health management, including unreliable sources and overburdened health care professionals. Research to ensure the proper design, implementation, and uptake of chatbots is imperative. Inclusive digital health research and responsible AI integration into health care require active and sustained patient and stakeholder engagement, yet corresponding activities and guidance are limited for this purpose. ObjectiveIn response, this manuscript presents a master protocol for the development, testing, and implementation of a chatbot family in partnership with stakeholders. This protocol aims to help efficiently translate an initial chatbot intervention (MARVIN) to multiple health domains and populations. MethodsThe MARVIN chatbots study has an adaptive platform trial design consisting of multiple parallel individual chatbot substudies with four common objectives: (1) co-construct a tailored AI chatbot for a specific health care setting, (2) assess its usability with a small sample of participants, (3) measure implementation outcomes (usability, acceptability, appropriateness, adoption, and fidelity) within a large sample, and (4) evaluate the impact of patient and stakeholder partnerships on chatbot development. For objective 1, a needs assessment will be conducted within the setting, involving four 2-hour focus groups with 5 participants each. Then, a co-construction design committee will be formed with patient partners, health care professionals, and researchers who will participate in 6 workshops for chatbot development, testing, and improvement. For objective 2, a total of 30 participants will interact with the prototype for 3 weeks and assess its usability through a survey and 3 focus groups. Positive usability outcomes will lead to the initiation of objective 3, whereby the public will be able to access the chatbot for a 12-month real-world implementation study using web-based questionnaires to measure usability, acceptability, and appropriateness for 150 participants and meta-use data to inform adoption and fidelity. After each objective, for objective 4, focus groups will be conducted with the design committee to better understand their perspectives on the engagement process. ResultsFrom July 2022 to October 2023, this master protocol led to four substudies conducted at the McGill University Health Centre or the Centre hospitalier de l’Université de Montréal (both in Montreal, Quebec, Canada): (1) MARVIN for HIV (large-scale implementation expected in mid-2024), (2) MARVIN-Pharma for community pharmacists providing HIV care (usability study planned for mid-2024), (3) MARVINA for breast cancer, and (4) MARVIN-CHAMP for pediatric infectious conditions (both in preparation, with development to begin in early 2024). ConclusionsThis master protocol offers an approach to chatbot development in partnership with patients and health care professionals that includes a comprehensive assessment of implementation outcomes. It also contributes to best practice recommendations for patient and stakeholder engagement in digital health research. Trial RegistrationClinicalTrials.gov NCT05789901; https://classic.clinicaltrials.gov/ct2/show/NCT05789901 International Registered Report Identifier (IRRID)PRR1-10.2196/54668
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- 2024
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261. 19 Using wearable technology data to explain recreational running injury: a prospective longitudinal feasibility study
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Christopher Napier, Bradley Neal, Isabel Moore, Christopher Bramah, Molly McCarthy-Ryan, Max Paquette, and Allison Gruber
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Medicine (General) ,R5-920 - Published
- 2024
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262. Brain structure and function: a multidisciplinary pipeline to study hominoid brain evolution
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Angela D. Friederici, Roman M. Wittig, Alfred Anwander, Cornelius Eichner, Tobias Gräßle, Carsten Jäger, Evgeniya Kirilina, Ilona Lipp, Ariane Düx, Luke J. Edwards, Cédric Girard-Buttoz, Anna Jauch, Kathrin S. Kopp, Michael Paquette, Kerrin J. Pine, Steve Unwin, Daniel B. M. Haun, Fabian H. Leendertz, Richard McElreath, Markus Morawski, Philipp Gunz, Nikolaus Weiskopf, Catherine Crockford, EBC Consortium, Daniel Ashoff, Karoline Albig, Bala Amarasekaran, Sam Angedakin, Caroline Asiimwe, Christian Bock, Birgit Blazey, Andreas Bernhard, Jacinta C Beehner, Laurent Bailanda, Raphael Belais, Thore J Bergman, Denny Böttcher, Tatiana Bortolato, Penelope Carlier, Julian Chantrey, Daniela Denk, Tobias Deschner, Dag Encke, Gelardine Escoubas, Malak Ettaj, Pawel Fedurek, Karina Flores, Alejandra Romero Florero, Richard Franke, Angela D Friederici, Cedric Girard-Buttoz, Jorge Gomez Fortun, Eva Gruber-Dujardin, Susan Hambrecht, Florian Hansmann, Jess Hartel, Daniel BM Haun, Michael Henshall, Catherine Hobaiter, Noémie Hofman, Jennifer E Jaffe, Stomy Karhemere, Evgenya Kirilina, Robert Klopfleisch, Tobias Knauf-Witzens, Kathrin Kopp, Bastian Lange, Kevin E Langergraber, Arne Lawrenz, Kevin Lee, Fabian H Leendertz, Illona Lipp, Matyas Liptovszky, Christelle Patricia Lumbu, Patrice Makouloutou Nzassi, Guy Landry Mamboundou Kouima, Kerstin Mätz-Rensing, Zoltan Mezö, Fanny Minesi, Sophie Moittie, Torsten Møller, Dave Morgan, Mathias Müller, Timothy Mugabe, Martin Muller, Karin Olofsson-Sannö, Alain Ondzie, Emily Otali, Simone Pika, Andrea Pizarro, Kamilla Pleh, Sandra Reichler-Danielowski, Jessica Rendel, Martha M Robbins, Konstantin Ruske, Liran Samuni, Crickette Sanz, Jan Schinköthe, André Schüle, Ingo Schwabe, Katarina Schwalm, Anistan Sebastiampillai, Lara Southern, Sheri Speede, Jonas Steiner, Mark F Stidworthy, Martin Surbeck, Claudia A. Szentiks, Tanguy Tanga, Tobias Loubser Theron, Reiner Ulrich, Erica van de Waal, Sue Walker, Gudrun Wibbelt, Navena Widulin, Hermann Will, Roman M Wittig, Kim Wood, Emiliano Zaccarella, and Klaus Zuberbühler
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non-human primates ,behavior ,structural MRI ,histology ,hominoid fossil ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
To decipher the evolution of the hominoid brain and its functions, it is essential to conduct comparative studies in primates, including our closest living relatives. However, strong ethical concerns preclude in vivo neuroimaging of great apes. We propose a responsible and multidisciplinary alternative approach that links behavior to brain anatomy in non-human primates from diverse ecological backgrounds. The brains of primates observed in the wild or in captivity are extracted and fixed shortly after natural death, and then studied using advanced MRI neuroimaging and histology to reveal macro- and microstructures. By linking detailed neuroanatomy with observed behavior within and across primate species, our approach provides new perspectives on brain evolution. Combined with endocranial brain imprints extracted from computed tomographic scans of the skulls these data provide a framework for decoding evolutionary changes in hominin fossils. This approach is poised to become a key resource for investigating the evolution and functional differentiation of hominoid brains.
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- 2024
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263. Validity of dried blood spot testing for sexually transmitted and blood-borne infections: A narrative systematic review.
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François Cholette, Simone Périnet, Bronwyn Neufeld, Maggie Bryson, Jennifer Macri, Kathryn M Sibley, John Kim, S Michelle Driedger, Marissa L Becker, Paul Sandstrom, Adrienne F A Meyers, and Dana Paquette
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Public aspects of medicine ,RA1-1270 - Abstract
Testing for human immunodeficiency virus (HIV) and hepatitis C virus (HCV) using dried blood spot (DBS) specimens has been an integral part of bio-behavioural surveillance in Canada for almost two decades, though less is known regarding the use of DBS in surveillance of other sexually transmitted and blood-borne infections (STBBI). A systematic review was conducted using a peer-reviewed search strategy to assess the current evidence regarding the validity of STBBI testing using DBS specimens. Eligibility criteria included studies reporting use of DBS specimens for STBBI testing with either commercially available or "in-house" tests in populations 15 years of age or older. Studies reporting a measure of validity such as sensitivity, specificity, positive and negative predictive values were eligible for inclusion. Quality of studies and risk of bias were assessed using the QUADAS-2 tool. A total of 7,132 records were identified. Of these, 174 met the criteria for inclusion. Among the studies that reported validity measures, a substantial proportion demonstrated high sensitivity (≥90%) in 62.5% of cases (N = 334/534 sensitivity measurements), and high specificity (≥90%) was observed in 84.9% of instances (N = 383/451 specificity measurements). However, the quality of the studies varied greatly. Our findings support the validity of the use of DBS specimens in STBBI testing where sufficient evidence was available, but validity is highly dependent on thorough method development and validation.
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- 2024
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264. Improving Cutaneous Wound Healing in Diabetic Mice Using Naturally Derived Tissue-Engineered Biological Dressings Produced under Serum-Free Conditions
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Meryem Safoine, Caroline Paquette, Gabrielle-Maude Gingras, and Julie Fradette
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Internal medicine ,RC31-1245 - Abstract
Long-term diabetes often leads to chronic wounds refractory to treatment. Cell-based therapies are actively investigated to enhance cutaneous healing. Various cell types are available to produce biological dressings, such as adipose-derived stem/stromal cells (ASCs), an attractive cell source considering their abundancy, accessibility, and therapeutic secretome. In this study, we produced human ASC-based dressings under a serum-free culture system using the self-assembly approach of tissue engineering. The dressings were applied every 4 days to full-thickness 8-mm splinted skin wounds created on the back of polygenic diabetic NONcNZO10/LtJ mice and streptozotocin-induced diabetic K14-H2B-GFP mice. Global wound closure kinetics evaluated macroscopically showed accelerated wound closure in both murine models, especially for NONcNZO10/LtJ; the treated group reaching 98.7% ± 2.3% global closure compared to 76.4% ± 11.8% for the untreated group on day 20 (p=0.0002). Histological analyses revealed that treated wounds exhibited healed skin of better quality with a well-differentiated epidermis and a more organized, homogeneous, and 1.6-fold thicker granulation tissue. Neovascularization, assessed by CD31 labeling, was 2.5-fold higher for the NONcNZO10/LtJ treated wounds. We thus describe the beneficial impact on wound healing of biologically active ASC-based dressings produced under an entirely serum-free production system facilitating clinical translation.
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- 2024
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265. Food environment trajectories: a sequence analysis from the CARTaGENE cohort
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Habila Adamou, Éric Robitaille, Marie-Claude Paquette, and Alexandre Lebel
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Food environment trajectory ,Sequence analysis ,Food stores ,Food environment ,Public aspects of medicine ,RA1-1270 ,Nutritional diseases. Deficiency diseases ,RC620-627 - Abstract
Abstract Objective: The purpose of this study was to create a typology of longitudinal exposure to food environment based on socio-economic context. Design: Food environment trajectories were modelled using a sequence analysis method, followed by a logistic regression to describe those trajectories. Setting: The study took place in Quebec, Canada, using food environment data from 2009, 2011 and 2018 merged with participants’ demographic and socio-economic characteristics. Participant: At recruitment, 38 627 participants between the ages of 40 and 69 years from six urban areas in Quebec were included in the CARTaGENE cohort study. The cohort was representative of the Quebec urban population within this age range. Results: Our study revealed five trajectories of food access over time: (1) limited access to food stores throughout the study period, (2) limited access improving, (3) good access diminishing, (4) good access throughout the period and (5) low access throughout the period. Logistic regression analysis showed that participants who were unable to work (OR = 1·42, CI = 1·08–1·86), lived in households with five or more persons (OR = 1·69, CI = 1·17–2·42) and those living in low-income households (OR = 1·32, CI = 1·03–1·71) had higher odds of experiencing a disadvantaged food environment trajectory. Additionally, the level of education and age of participants were associated with the odds of experiencing a disadvantaged food environment trajectory. Conclusions: The study demonstrates that people facing socio-economic disadvantage are more likely to experience a disadvantaged food environment trajectory over time.
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- 2024
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266. Ultra-processed and fast food consumption, exposure to phthalates during pregnancy, and socioeconomic disparities in phthalate exposures
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Brennan H. Baker, Melissa M. Melough, Alison G. Paquette, Emily S. Barrett, Drew B. Day, Kurunthachalam Kannan, Ruby HN Nguyen, Nicole R. Bush, Kaja Z. LeWinn, Kecia N. Carroll, Shanna H. Swan, Qi Zhao, and Sheela Sathyanarayana
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Phthalates ,Processed food ,NOVA ,Fast food ,Maternal diet ,Endocrine disruptors ,Environmental sciences ,GE1-350 - Abstract
Background: Consuming ultra-processed foods may increase exposure to phthalates, a group of endocrine disruptors prevalent in food contact materials. Objectives: Investigate associations between ultra-processed food intake and urinary phthalates during pregnancy, and evaluate whether ultra-processed foods mediate socioeconomic disparities in phthalate exposures. Methods: In a socioeconomically diverse sample of 1031 pregnant women from the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) Study in the urban South, the Block Food Frequency Questionnaire was administered and urinary phthalate metabolites were measured in the second trimester. Linear regressions modeled associations between phthalates and overall ultra-processed food consumption, individual ultra-processed foods, and exploratory factor analysis dietary patterns. Causal mediation analyses examined whether ultra-processed food intake mediates relationships between socioeconomic disparities and phthalate exposures. Results: Ultra-processed foods constituted 9.8–59.0 % (mean = 38.6 %) of participants’ diets. 10 % higher dietary proportion of ultra-processed foods was associated with 13.1 % (95 %CI: 3.4 %–22.9 %) higher molar sum concentrations of di(2-ethylhexyl) phthalate metabolites (ΣDEHP). 10 % higher consumption of minimally-processed foods was associated with lower ΣDEHP (10.8 %: 3.4 %–22.9 %). Ultra- and minimally-processed food consumption were not associated with non-DEHP metabolites. Standard deviation higher consumptions of hamburger/cheeseburger, French fries, soda, and cake were associated with 10.5 % (4.2 %-17.1 %), 9.2 % (2.6 %-16.2 %), 7.4 % (1.4 %-13.6 %), and 6.0 % (0.0 %-12.4 %), respectively, higher ΣDEHP. Exploratory factor analysis corroborated positive associations of processed food with ΣDEHP, and uncovered a healthy dietary pattern associated with lower urinary ΣDEHP, mono(2-ethyl-5-hydroxyhexyl) (MEHHP), mono(2-ethyl-5-carboxypentyl) (MECPP), mono(2-carboxymethylhexyl) (MCMHP), and mono-isononyl (MINP) phthalates. Significant indirect effects indicated that lower income and education levels were associated with 1.9 % (0.2 %-4.2 %) and 1.4 % (0.1 %-3.3 %) higher ΣDEHP, respectively, mediated via increased ultra-processed food consumption. Conclusions: Consumption of ultra-processed foods may increase exposure to phthalates. Policies to reduce dietary phthalate exposures from food packaging and processing are needed, as socioeconomic barriers can preclude dietary recommendations as a sole means to reduce phthalate exposures.
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- 2024
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267. Secular Coefficients and the Holomorphic Multiplicative Chaos
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Najnudel, Joseph, Paquette, Elliot, and Simm, Nick
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Mathematics - Probability ,Mathematical Physics ,Mathematics - Combinatorics ,60B20, 60F05, 60G42 - Abstract
We study the secular coefficients of $N \times N$ random unitary matrices $U_{N}$ drawn from the Circular $\beta$-Ensemble, which are defined as the coefficients of $\{z^n\}$ in the characteristic polynomial $\det(1-zU_{N}^{*})$. When $\beta > 4$ we obtain a new class of limiting distributions that arise when both $n$ and $N$ tend to infinity simultaneously. We solve an open problem of Diaconis and Gamburd by showing that for $\beta=2$, the middle coefficient tends to zero as $N \to \infty$. We show how the theory of Gaussian multiplicative chaos (GMC) plays a prominent role in these problems and in the explicit description of the obtained limiting distributions. We extend the remarkable magic square formula of Diaconis and Gamburd for the moments of secular coefficients to all $\beta>0$ and analyse the asymptotic behaviour of the moments. We obtain estimates on the order of magnitude of the secular coefficients for all $\beta > 0,$ and these estimates are sharp when $\beta \geq 2$. These insights motivated us to introduce a new stochastic object associated with the secular coefficients, which we call Holomorphic Multiplicative Chaos (HMC). Viewing the HMC as a random distribution, we prove a sharp result about its regularity in an appropriate Sobolev space. Our proofs expose and exploit several novel connections with other areas, including random permutations, Tauberian theorems and combinatorics.
- Published
- 2020
268. Fun with $F_{24}$
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Harrison, Sarah M., Paquette, Natalie M., Persson, Daniel, and Volpato, Roberto
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High Energy Physics - Theory ,Mathematics - Quantum Algebra ,Mathematics - Representation Theory - Abstract
We study some special features of $F_{24}$, the holomorphic $c=12$ superconformal field theory (SCFT) given by 24 chiral free fermions. We construct eight different Lie superalgebras of "physical" states of a chiral superstring compactified on $F_{24}$, and we prove that they all have the structure of Borcherds-Kac-Moody superalgebras. This produces a family of new examples of such superalgebras. The models depend on the choice of an $\mathcal{N}=1$ supercurrent on $F_{24}$, with the admissible choices labeled by the semisimple Lie algebras of dimension 24. We also discuss how $F_{24}$, with any such choice of supercurrent, can be obtained via orbifolding from another distinguished $c=12$ holomorphic SCFT, the $\mathcal{N}=1$ supersymmetric version of the chiral CFT based on the $E_8$ lattice., Comment: 46 pages. v2: minor corrections
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- 2020
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269. Strong approximation of Gaussian $\beta$-ensemble characteristic polynomials: the edge regime and the stochastic Airy function
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Lambert, Gaultier and Paquette, Elliot
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Mathematics - Probability ,Mathematical Physics - Abstract
We investigate the characteristic polynomials of the Gaussian $\beta$-ensemble for general $\beta>0$ through its transfer matrix recurrence. We show that the rescaled characteristic polynomial converges to a random entire function in a neighborhood of the edge of the limiting spectrum. This random entire function, called the stochastic Airy function, is the unique (up to scaling) $L^2$ solution to the stochastic Airy equation, a family of second order stochastic differential equations. Moreover, we obtain a coupling between the characteristic polynomial and a solution of the stochastic Airy equation which allows us to show that for any $\epsilon>0$, these two function are uniformly close by $N^{-1/6 + \epsilon}$ with overwhelming probability. These results build on the results of the authors in which the hyperbolic portion of the transfer matrix recurrence for the characteristic polynomial is analyzed., Comment: Second, submitted version. Greatly strengthens main theorem over the first version to be a quantitative between the stochastic Airy function and the characteristic polynomial
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- 2020
270. Anchored expansion of Delaunay complexes in real hyperbolic space and stationary point processes
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Benjamini, Itai, Krauz, Yoav, and Paquette, Elliot
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Mathematics - Probability ,Mathematics - Metric Geometry ,60G55, 51F30, 54E70, 20F67 - Abstract
We give sufficient conditions for a discrete set of points in any dimensional real hyperbolic space to have positive anchored expansion. The first condition is a bounded mean density property, ensuring not too many points can accumulate in large regions. The second is a bounded mean vacancy condition, effectively ensuring there is not too much space left vacant by the points over large regions. These properties give as an easy corollary that stationary Poisson--Delaunay graphs have positive anchored expansion, as well as Delaunay graphs built from stationary determinantal point processes. We introduce a family of stationary determinantal point processes on any dimension of real hyperbolic space, the Berezin point processes, and we partially characterize them. We pose many questions related to this process and stationary determinantal point processes., Comment: 27 pages. 6 figures. Third version includes referee corrections, plus additional sections not in published version (Sections 5, 1.3)
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- 2020
271. Universality for the conjugate gradient and MINRES algorithms on sample covariance matrices
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Paquette, Elliot and Trogdon, Thomas
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Mathematics - Numerical Analysis ,Mathematics - Probability ,65F10, 60B20 - Abstract
We present a probabilistic analysis of two Krylov subspace methods for solving linear systems. We prove a central limit theorem for norms of the residual vectors that are produced by the conjugate gradient and MINRES algorithms when applied to a wide class of sample covariance matrices satisfying some standard moment conditions. The proof involves establishing a four moment theorem for the so-called spectral measure, implying, in particular, universality for the matrix produced by the Lanczos iteration. The central limit theorem then implies an almost-deterministic iteration count for the iterative methods in question.
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- 2020
272. Interval fragmentations with choice: equidistribution and the evolution of tagged fragments
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Maillard, Pascal and Paquette, Elliot
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Mathematics - Probability ,Mathematics - Analysis of PDEs ,60J25, 45K05 - Abstract
We consider a Markovian evolution on point processes, the $\Psi$--process, on the unit interval in which points are added according to a rule that depends only on the spacings of the existing point configuration. Having chosen a spacing, a new point is added uniformly within it. Building on previous work of the authors and of Junge, we show that the empirical distribution of points in such a process is always equidistributed under mild assumptions on the rule, generalizing work of Junge. A major portion of this article is devoted to the study of a particular growth--fragmentation process, or cell process, which is a type of piecewise--deterministic Markov process (PDMP). This process represents a linearized version of a size--biased sampling from the $\Psi$--process. We show that this PDMP is ergodic and develop the semigroup theory of it, to show that it describes a linearized version of the $\Psi$--process. This PDMP has appeared in other contexts, and in some sense we develop its theory under minimal assumptions.
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- 2020
273. Conductive filament evolution dynamics revealed by cryogenic (1.5 K) multilevel switching of CMOS-compatible Al2O3/TiO2 resistive memories
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Beilliard, Yann, Paquette, François, Brousseau, Frédéric, Ecoffey, Serge, Alibart, Fabien, and Drouin, Dominique
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Physics - Applied Physics - Abstract
This study demonstrates multilevel switching at 1.5 K of Al2O3/TiO2-x resistive memory devices fabricated with CMOS-compatible processes and materials. The I-V characteristics exhibit a negative differential resistance (NDR) effect due to a Joule-heating-induced metal-insulator transition of the Ti4O7 conductive filament. Carrier transport analysis of all multilevel switching I-V curves show that while the insulating regime follows the space charge limited current (SCLC) model for all resistance states, the conduction in the metallic regime is dominated by SCLC and trap-assisted tunneling (TAT) for low- and high-resistance states respectively. A non-monotonic conductance evolution is observed in the insulating regime, as opposed to the continuous and gradual conductance increase and decrease obtained in the metallic regime during the multilevel SET and RESET operations. Cryogenic transport analysis coupled to an analytical model accounting for the metal-insulator-transition-induced NDR effects and the resistance states of the device provide new insights on the conductive filament evolution dynamics and resistive switching mechanisms. Our findings suggest that the non-monotonic conductance evolution in the insulating regime is due to the combined effects of longitudinal and radial variations of the Ti4O7 conductive filament during the switching. This behavior results from the interplay between temperature- and field-dependent geometrical and physical characteristics of the filament., Comment: 8 pages, 4 figures
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- 2020
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274. Completions of discrete cluster categories of type $\mathbb{A}$
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Paquette, Charles and Yildirim, Emine
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Mathematics - Representation Theory ,18E30, 16G20 - Abstract
We complete the discrete cluster categories of type $\mathbb{A}$ as defined by Igusa and Todorov, by embedding such a discrete cluster category inside a larger one, and then taking a certain Verdier quotient. The resulting category is a Hom-finite Krull-Schmidt triangulated category containing the discrete cluster category as a full subcategory. The objects and Hom-spaces in this new category can be described geometrically, even though the category is not $2$-Calabi-Yau and Ext-spaces are not always symmetric. We describe all cluster-tilting subcategories. Given such a subcategory, we define a cluster character that takes values in a ring with infinitely many indeterminates. Our cluster character is new in that it takes into account infinite dimensional sub-representations of infinite dimensional ones. We show that it satisfies the multiplication formula and also the exchange formula, provided that the objects being exchanged satisfy some local Calabi-Yau conditions., Comment: 33 pages, 11 figures
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- 2020
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275. An Effective Field Theory for Fractional Quantum Hall Systems near $\nu=5/2$
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Hsin, Po-Shen, Lin, Ying-Hsuan, Paquette, Natalie M., and Wang, Juven
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Condensed Matter - Strongly Correlated Electrons ,Condensed Matter - Mesoscale and Nanoscale Physics ,High Energy Physics - Theory - Abstract
We propose an effective field theory (EFT) of fractional quantum Hall systems near the filling fraction $\nu=5/2$ that flows to pertinent IR candidate phases, including non-abelian Pfaffian, anti-Pfaffian, and particle-hole Pfaffian states (Pf, APf, and PHPf). Our EFT has a 2+1$d$ O(2)$_{2,L}$ Chern-Simons gauge theory coupled to four Majorana fermions by a discrete charge conjugation gauge field, with Gross-Neveu-Yukawa-Higgs terms. Including deformations via a Higgs condensate and fermion mass terms, we can map out a phase diagram with tunable parameters, reproducing the prediction of the recently-proposed percolation picture and its gapless topological quantum phase transitions. Our EFT captures known features of both gapless and gapped sectors of time-reversal-breaking domain walls between Pf and APf phases. Moreover, we find that Pf$\mid$APf domain walls have higher tension than domain walls in the PHPf phase. Then the former, if formed, may transition to the energetically-favored PHPf domain walls; this could, in turn, help further induce a bulk transition to PHPf., Comment: 72 pages, 10 figures, 5 tables. Many appendices. Add Sec 2.2, new remarks in Conclusion, and other clarifications. Accepted by Physical Review Research
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- 2020
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276. A termination criterion for stochastic gradient descent for binary classification
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Baghal, Sina, Paquette, Courtney, and Vavasis, Stephen A.
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Mathematics - Optimization and Control ,Statistics - Machine Learning - Abstract
We propose a new, simple, and computationally inexpensive termination test for constant step-size stochastic gradient descent (SGD) applied to binary classification on the logistic and hinge loss with homogeneous linear predictors. Our theoretical results support the effectiveness of our stopping criterion when the data is Gaussian distributed. This presence of noise allows for the possibility of non-separable data. We show that our test terminates in a finite number of iterations and when the noise in the data is not too large, the expected classifier at termination nearly minimizes the probability of misclassification. Finally, numerical experiments indicate for both real and synthetic data sets that our termination test exhibits a good degree of predictability on accuracy and running time.
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- 2020
277. A Road Map to Strong Intelligence
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Paquette, Philip
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Computer Science - Artificial Intelligence ,Computer Science - Computers and Society ,Computer Science - Machine Learning - Abstract
I wrote this paper because technology can really improve people's lives. With it, we can live longer in a healthy body, save time through increased efficiency and automation, and make better decisions. To get to the next level, we need to start looking at intelligence from a much broader perspective, and promote international interdisciplinary collaborations. Section 1 of this paper delves into sociology and social psychology to explain that the mechanisms underlying intelligence are inherently social. Section 2 proposes a method to classify intelligence, and describes the differences between weak and strong intelligence. Section 3 examines the Chinese Room argument from a different perspective. It demonstrates that a Turing-complete machine cannot have strong intelligence, and considers the modifications necessary for a computer to be intelligent and have understanding. Section 4 argues that the existential risk caused by the technological explosion of a single agent should not be of serious concern. Section 5 looks at the AI control problem and argues that it is impossible to build a super-intelligent machine that will do what it creators want. By using insights from biology, it also proposes a solution to the control problem. Section 6 discusses some of the implications of strong intelligence. Section 7 lists the main challenges with deep learning, and asserts that radical changes will be required to reach strong intelligence. Section 8 examines a neuroscience framework that could help explain how a cortical column works. Section 9 lays out the broad strokes of a road map towards strong intelligence. Finally, section 10 analyzes the impacts and the challenges of greater intelligence.
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- 2020
278. Gaussian analytic functions of bounded mean oscillation
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Nishry, Alon and Paquette, Elliot
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Mathematics - Complex Variables ,Mathematics - Probability ,30B20 (Primary), 30H35, 47B80 (Secondary) - Abstract
We consider random analytic functions given by a Taylor series with independent, centered complex Gaussian coefficients. We give a new sufficient condition for such a function to have bounded mean oscillations. Under a mild regularity assumption this condition is optimal. Using a theorem of Holland and Walsh, we give as a corollary a new bound for the norm of a random Gaussian Hankel matrix. Finally, we construct some exceptional Gaussian analytic functions which in particular disprove the conjecture that a random analytic function with bounded mean oscillations always has vanishing mean oscillations., Comment: 33 pages
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- 2020
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279. Strong approximation of Gaussian beta-ensemble characteristic polynomials: the hyperbolic regime
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Lambert, Gaultier and Paquette, Elliot
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Mathematics - Probability - Abstract
We investigate the characteristic polynomials $\varphi_N$ of the Gaussian $\beta$-ensemble for general $\beta>0$ through its transfer matrix recurrence. Our motivation is to obtain a (probabilistic) approximation for $\varphi_N$ in terms of a Gaussian log--correlated field in order to ultimately deduce some of its fine asymptotic properties. We distinguish between different types of transfer matrices and analyze completely the hyperbolic regime of the recurrence. As a result, we obtain a new coupling between $\varphi_N(z)$ and a Gaussian analytic function with an error which is uniform for $z \in \mathbb{C}$ separated from the support of the semicircle law. We use this as input to give the almost sure scaling limit of the characteristic polynomial at the edge in arXiv:2009.05003. This is also required to obtain analogous strong approximations inside of the bulk of the semicircle law. Our analysis relies on moderate deviation estimates for the product of transfer matrices and this approach might also be useful in different contexts., Comment: Version 4. Implemented referee comments and added section on chaos convergence
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- 2020
280. Topology of random 2-dimensional cubical complexes
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Kahle, Matthew, Paquette, Elliot, and Roldán, Érika
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Mathematics - Combinatorics ,Mathematics - Algebraic Topology ,Mathematics - Probability - Abstract
We study a natural model of random 2-dimensional cubical complex which is a subcomplex of an n-dimensional cube, and where every possible square $2$-face is included independently with probability p. Our main result is to exhibit a sharp threshold p=1/2 for homology vanishing as $n \to \infty$. This is a 2-dimensional analogue of the Burtin and Erd\H{o}s-Spencer theorems characterizing the connectivity threshold for random cubical graphs. Our main result can also be seen as a cubical counterpart to the Linial--Meshulam theorem for random 2-dimensional simplicial complexes. However, the models exhibit strikingly different behaviors. We show that if $p > 1 - \sqrt{1/2} \approx 0.2929$, then with high probability the fundamental group is a free group with one generator for every maximal $1$-dimensional face. As a corollary, homology vanishing and simple connectivity have the same threshold, even in the strong "hitting time" sense. This is in contrast with the simplicial case, where the thresholds are far apart. The proof depends on an iterative algorithm for contracting cycles -- we show that with high probability the algorithm rapidly and dramatically simplifies the fundamental group, converging after only a few steps., Comment: Third version. Presentation improvements
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- 2020
281. Twisted Supergravity and Koszul Duality: A case study in AdS$_3$
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Costello, Kevin and Paquette, Natalie M.
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High Energy Physics - Theory - Abstract
In this note, we study a simplified variant of the familiar holographic duality between supergravity on AdS$_3\times S^3\times T^4$ and the SCFT (on the moduli space of) the symmetric orbifold theory $Sym^N(T^4)$ as $N \rightarrow \infty$. This variant arises conjecturally from a twist proposed by the first author and Si Li. We recover a number of results concerning protected subsectors of the original duality working directly in the twisted bulk theory. Moreover, we identify the symmetry algebra arising in the $N\rightarrow \infty$ limit of the twisted gravitational theory. We emphasize the role of $\textit{Koszul duality}$---a ubiquitous mathematical notion to which we provide a friendly introduction---in field theory and string theory. After illustrating the appearance of Koszul duality in the "toy" example of holomorphic Chern-Simons theory, we describe how (a deformation of) Koszul duality relates bulk and boundary operators in our twisted setup, and explain how one can compute algebra OPEs diagrammatically using this notion. Further details, results, and computations will appear in a companion paper., Comment: 80 pages, 9 figures
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- 2020
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282. Spontaneous Scaling of a Primary Care Innovation in Real-Life Conditions: Protocol for a Case Study
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France Légaré, Diogo G V Mochcovitch, Roberta de Carvalho Corôa, Amédé Gogovor, Ali Ben Charif, Cynthia Cameron, Annie Plamondon, Marie Cimon, Sabrina Guay-Bélanger, Geneviève Roch, Maxine Dumas Pilon, Jean-Sébastien Paquette, Robert K D McLean, and Andrew Milat
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Medicine ,Computer applications to medicine. Medical informatics ,R858-859.7 - Abstract
BackgroundScaling effective primary care innovations to benefit more people is of interest to decision makers. However, we know little about how promising innovations are being scaled “spontaneously,” that is, without deliberate guidance. ObjectiveWe aim to observe, document, and analyze how, in real-life conditions, 1 primary care innovation spontaneously scales up across Quebec, Canada. MethodsWe will conduct a participative study using a descriptive single-case study. It will be guided by the McLean and Gargani principles for scaling and reported according to the COREQ (Consolidated Criteria for Reporting Qualitative Research) guidelines. Informed by an integrated knowledge translation approach, our steering committee will include patient users throughout the project. Inspired by the Quebec College of Family Physician’s “Dragons’ Den” primary care program, we will identify a promising primary care innovation that is being or will be scaled spontaneously. We will interview the innovation team about their scaling experiences every month for 1 year. We will conduct interviews and focus groups with decision makers, health care providers, and end users in the innovation team and the target site about their experience of both scaling and receiving the scaled innovation and document meetings as nonparticipant observers. Interview transcripts and documentary data will be analyzed to (1) compare the spontaneous scaling plan and implementation with the McLean and Gargani principles for scaling and (2) determine how it was consistent with or diverged from the 4 McLean and Gargani guiding principles: justification, optimal scale, coordination, and dynamic evaluation. ResultsThis study was funded in March 2020 by the Canadian Institutes of Health Research. Recruitment began in November 2023 and data collection began in December 2023. Results are expected to be published in the first quarter of 2024. ConclusionsOur study will advance the science of scaling by providing practical evidence–based material about scaling health and social care innovations in real-world settings using the 4 guiding principles of McLean and Gargani. International Registered Report Identifier (IRRID)PRR1-10.2196/54855
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- 2023
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283. It takes a village to grow a tree: Most tree species benefit from dissimilar neighbors
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Vanessa Di Maurizio, Eric Searle, and Alain Paquette
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complementarity hypothesis ,diversity‐productivity relationship ,functional dissimilarity ,functional traits ,neighborhood analysis ,tree growth ,Ecology ,QH540-549.5 - Abstract
Abstract Scientific consensus is that diverse tree species positively impact forest productivity, especially when species are functionally dissimilar. Under the complementarity hypothesis, differences in species traits reduce competition among neighboring tree species. However, while this relationship has been extensively studied at the community level, there is a lack of understanding regarding how individuals of different species specifically respond to a functionally dissimilar neighborhood. In this study, we used permanent plots from Quebec, Canada, and 19 focal tree species to test whether: (1) tree growth response to neighborhood dissimilarity varies with their identity and competition intensity, and (2) focal tree species’ traits explain their response to neighborhood dissimilarity. We demonstrate that: tree growth is primarily influenced by competition, species identity, and their interactions, but that dissimilarity, alone and in interaction with the main drivers of tree growth, explains an additional 1.8% of the variation in species growth. Within this context, (1) most species’ respond positively to neighborhood dissimilarity, with magnitude being species and competition dependent, and (2) focal tree traits partly explain these dependencies, with shade‐intolerant species benefiting most from dissimilar neighbors under high competition. Our study provides empirical support for the complementarity hypothesis, emphasizing the small but consistent positive effect of functional dissimilarity on tree growth in local neighborhoods. Our findings identify the species with the highest potential of benefiting from dissimilar neighbors but also demonstrate that the positive effect of neighborhood dissimilarity is not limited to a select few species with specific traits; rather, it is observed across a diverse range of species. The cumulative growth responses of individuals to functionally dissimilar neighbors may help explain the commonly observed higher productivity in more diverse communities.
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- 2023
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284. Pattern of neurological recovery in persons with an acute cervical spinal cord injury over the first 14 days post injury
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Nader Fallah, Vanessa K. Noonan, Zeina Waheed, Raphaele Charest-Morin, Charlotte Dandurand, Christiana Cheng, Tamir Ailon, Nicolas Dea, Scott Paquette, John T. Street, Charles Fisher, Marcel F. Dvorak, and Brian K. Kwon
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acute cervical spinal cord injury ,motor recovery trajectory ,baseline neurological assessment ,upper-extremity motor score ,total motor score ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
IntroductionFollowing a traumatic spinal cord injury (SCI) it is critical to document the level and severity of injury. Neurological recovery occurs dynamically after injury and a baseline neurological exam offers a snapshot of the patient's impairment at that time. Understanding when this exam occurs in the recovery process is crucial for discussing prognosis and acute clinical trial enrollment. The objectives of this study were to: (1) describe the trajectory of motor recovery in persons with acute cervical SCI in the first 14 days post-injury; and (2) evaluate if the timing of the baseline neurological assessment in the first 14 days impacts the amount of motor recovery observed.MethodsData were obtained from the Rick Hansen Spinal Cord Injury Registry (RHSCIR) site in Vancouver and additional neurological data was extracted from medical charts. Participants with a cervical injury (C1–T1) who had a minimum of three exams (including a baseline and discharge exam) were included. Data on the upper-extremity motor score (UEMS), total motor score (TMS) and American Spinal Injury Association (ASIA) Impairment Scale (AIS) were included. A linear mixed-effect model with additional variables (AIS, level of injury, UEMS, time, time2, and TMS) was used to explore the pattern and amount of motor recovery over time.ResultsTrajectories of motor recovery in the first 14 days post-injury showed significant improvements in both TMS and UEMS for participants with AIS B, C, and D injuries, but was not different for high (C1–4) vs. low (C5–T1) cervical injuries or AIS A injuries. The timing of the baseline neurological examination significantly impacted the amount of motor recovery in participants with AIS B, C, and D injuries.DiscussionTiming of baseline neurological exams was significantly associated with the amount of motor recovery in cervical AIS B, C, and D injuries. Studies examining changes in neurological recovery should consider stratifying by severity and timing of the baseline exam to reduce bias amongst study cohorts. Future studies should validate these estimates for cervical AIS B, C, and D injuries to see if they can serve as an “adjustment factor” to control for differences in the timing of the baseline neurological exam.
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- 2023
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285. Partage d’une « expérience leçon » d’une recherche de nature quantitative menée auprès d’enfants à l’éducation préscolaire : piste de réflexion
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Noémie Paquette, Christelle Robert-Mazaye, Geneviève Tardif, and Johanne April
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Education - Abstract
L’inclusion de jeunes enfants comme sujets participants à la recherche est un phénomène nouveau qui gagne en popularité. Toutefois, leur participation comporte plusieurs défis qui nécessitent des adaptations. Une collecte de données de nature quantitative réalisée auprès de cette population a mené à l’identification de deux écueils importants. Le premier concerne le fait que l’enfant participant est généralement placé dans un rôle d’exécutant. Le second prend appui sur le premier et porte sur l’écart entre ce que nous souhaitons obtenir comme résultats, nos approches et nos objectifs de recherche. En conclusion, nous avançons que pour faire de la recherche porteuse de sens auprès de jeunes enfants, nous devons inévitablement transcender la démarche de recherche et oser porter un regard critique et réflexif sur nos pratiques de recherche.
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- 2023
286. Perfusion Assessment in Left-Sided/Low Anterior Resection (PILLAR III): A Randomized, Controlled, Parallel, Multicenter Study Assessing Perfusion Outcomes With PINPOINT Near-Infrared Fluorescence Imaging in Low Anterior Resection.
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Jafari, Mehraneh D, Pigazzi, Alessio, McLemore, Elisabeth C, Mutch, Matthew G, Haas, Eric, Rasheid, Sowsan H, Wait, Alyssa D, Paquette, Ian M, Bardakcioglu, Ovunc, Safar, Bashar, Landmann, Ron G, Varma, Madhulika G, Maron, David J, Martz, Joseph, Bauer, Joel J, George, Virgilio V, Fleshman, James W, Steele, Scott R, and Stamos, Michael J
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Colon ,Rectum ,Humans ,Rectal Neoplasms ,Indocyanine Green ,Fluoroscopy ,Intraoperative Care ,Anastomosis ,Surgical ,Middle Aged ,Female ,Male ,Anastomotic Leak ,Optical Imaging ,Anastomotic leak ,Angiography ,Colorectal anastomosis ,Indocyanine green ,Perfusion ,Clinical Research ,Prevention ,Clinical Trials and Supportive Activities ,Clinical Sciences ,Surgery - Abstract
BackgroundIndocyanine green fluoroscopy has been shown to improve anastomotic leak rates in early phase trials.ObjectiveWe hypothesized that the use of fluoroscopy to ensure anastomotic perfusion may decrease anastomotic leak after low anterior resection.DesignWe performed a 1:1 randomized controlled parallel study. Recruitment of 450 to 1000 patients was planned over 2 years.SettingsThis was a multicenter trial.PatientsIncluded patients were those undergoing resection defined as anastomosis within 10 cm of the anal verge.InterventionPatients underwent standard evaluation of tissue perfusion versus standard in conjunction with perfusion evaluation using indocyanine green fluoroscopy.Main outcome measuresPrimary outcome was anastomotic leak, with secondary outcomes of perfusion assessment and the rate of postoperative abscess requiring intervention.ResultsThis study was concluded early because of decreasing accrual rates. A total of 25 centers recruited 347 patients, of whom 178 were randomly assigned to perfusion and 169 to standard. The groups had comparable tumor-specific and patient-specific demographics. Neoadjuvant chemoradiation was performed in 63.5% of perfusion and 65.7% of standard (p > 0.05). Mean level of anastomosis was 5.2 ± 3.1 cm in perfusion compared with 5.2 ± 3.3 cm in standard (p > 0.05). Sufficient visualization of perfusion was reported in 95.4% of patients in the perfusion group. Postoperative abscess requiring surgical management was reported in 5.7% of perfusion and 4.2% of standard (p = 0.75). Anastomotic leak was reported in 9.0% of perfusion compared with 9.6% of standard (p = 0.37). On multivariate regression analysis, there was no difference in anastomotic leak rates between perfusion and standard (OR = 0.845 (95% CI, 0.375-1.905); p = 0.34).LimitationsThe predetermined sample size to adequately reduce the risk of type II error was not achieved.ConclusionsSuccessful visualization of perfusion can be achieved with indocyanine green fluoroscopy. However, no difference in anastomotic leak rates was observed between patients who underwent perfusion assessment versus standard surgical technique. In experienced hands, the addition of routine indocyanine green fluoroscopy to standard practice adds no evident clinical benefit. See Video Abstract at http://links.lww.com/DCR/B560.Valoracin de la irrigacin de lado izquierdo/reseccin anterior baja pilar iii un estudio aleatorizado, controlado, paralelo y multicntrico que evala los resultados de la irrigacin con pinpoint imgenes de fluorescencia cercana al infrarrojo en la reseccin anterior bajaANTECEDENTES:Se ha demostrado que la fluoroscopia con verde de indocianina mejora las tasas de fuga anastomótica en ensayos en fases iniciales.OBJETIVO:Nuestra hipótesis es que la utilización de fluoroscopia para asegurar la irrigación anastomótica puede disminuir la fuga anastomótica luego de una resección anterior baja.DISEÑO:Realizamos un estudio paralelo, controlado, aleatorizado 1:1. Se planificó el reclutamiento de 450-1000 pacientes durante 2 años.AMBITO:Multicéntrico.PACIENTES:Pacientes sometidos a resección definida como una anastomosis dentro de los 10cm del margen anal.INTERVENCIÓN:Pacientes que se sometieron a la evaluación estándar de la irrigación tisular contra la estándar en conjunto con la valoración de la irrigación mediante fluoroscopia con verde indocianina.PRINCIPALES VARIABLES EVALUADAS:El principal resultado fue la fuga anastomótica, y los resultados secundarios fueron la evaluación de la perfusión y la tasa de absceso posoperatorio que requirió intervención.RESULTADOS:Este estudio se cerró anticipadamente debido a la disminución de las tasas de acumulación. Un total de 25 centros reclutaron a 347 pacientes, de los cuales 178 fueron, de manera aleatoria, asignados a perfusión y 169 a estándar. Los grupos tenían datos demográficos específicos del tumor y del paciente similares. Recibieron quimio-radioterapia neoadyuvante el 63,5% de la perfusión y el 65,7% del estándar (p> 0,05). La anastomosis estuvo en un nivel promedio de 5,2 + 3,1 cm en perfusión en comparación con 5,2 + 3,3 cm en estándar (p> 0,05). Se reportó una visualización suficiente de la perfusión en el 95,4% de los pacientes del grupo de perfusión. El absceso posoperatorio que requirió tratamiento quirúrgico fue de 5,7% de los perfusion y en el 4,2% del estándar (p = 0,75). Se informó fuga anastomótica en el 9,0% de la perfusión en comparación con el 9,6% del estándar (p = 0,37). En el análisis de regresión multivariante, no hubo diferencias en las tasas de fuga anastomótica entre la perfusión y el estándar (OR 0,845; IC del 95% (0,375; 1,905); p = 0,34).LIMITACIONES:No se logró el tamaño de muestra predeterminado para reducir satisfactoriamente el riesgo de error tipo II.CONCLUSIÓN:Se puede obtener una visualización adecuada de la perfusión con ICG-F. Sin embargo, no se observaron diferencias en las tasas de fuga anastomótica entre los pacientes que se sometieron a evaluación de la perfusión versus la técnica quirúrgica estándar. En manos expertas, agregar ICG-F a la rutina de la práctica estándar no agrega ningún beneficio clínico evidente. Consulte Video Resumen en http://links.lww.com/DCR/B560. (Traducción-Dr Juan Antonio Villanueva-Herrero).
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- 2021
287. The Morphological, Elastic, and Electric Properties of Dust Aggregates in Comets: A Close Look at COSIMA/Rosetta's Data on Dust in Comet 67P/Churyumov-Gerasimenko
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Kimura, Hiroshi, Hilchenbach, Martin, Merouane, Sihane, Paquette, John, and Stenzel, Oliver
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Astrophysics - Earth and Planetary Astrophysics - Abstract
The Cometary Secondary Ion Mass Analyzer (COSIMA) onboard ESA's Rosetta orbiter has revealed that dust particles in the coma of Comet 67P/Churyumov-Gerasimenko are aggregates of small grains. We study the morphological, elastic, and electric properties of dust aggregates in the coma of Comet 67P/Churyumov-Gerasimenko using optical microscopic images taken by the COSIMA instrument. Dust aggregates in COSIMA images are well represented as fractals in harmony with morphological data from MIDAS (Micro-Imaging Dust Analysis System) and GIADA (Grain Impact Analyzer and Dust Accumulator) onboard Rosetta. COSIMA's images, together with the data from the other Rosetta's instruments such as MIDAS and GIADA do not contradict the so-called rainout growth of $10~\mu\mathrm{m}$-sized particles in the solar nebula. The elastic and electric properties of dust aggregates measured by COSIMA suggest that the surface chemistry of cometary dust is well represented as carbonaceous matter rather than silicates or ices, consistent with the mass spectra, and that organic matter is to some extent carbonized by solar radiation, as inferred from optical and infrared observations of various comets. Electrostatic lofting of cometary dust by intense electric fields at the terminator of its parent comet is unlikely, unless the surface chemistry of the dust changes from a dielectric to a conductor. Our findings are not in conflict with our current understanding of comet formation and evolution, which begin with the accumulation of condensates in the solar nebula and follow with the formation of a dust mantle in the inner solar system., Comment: 17 pages, 12 figures, 1 tables, to appear in Planetary and Space Science
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- 2019
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288. On the speed of distance stationary sequences
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Carrasco, Matias, Lessa, Pablo, and Paquette, Elliot
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Mathematics - Probability - Abstract
We prove a formula for the speed of distance stationary random sequences generalizing the law of large numbers of Karlsson and Ledrappier. A particular case is the classical formula for the largest Lyapunov exponent of i.i.d.\ matrix products, but our result has applications in various different contexts. In many situations it gives a method to estimate the speed, and in others it allows to obtain results of dimension drop for escape measures related to random walks. We show applications to stationary reversible random trees with conductances, Bernoulli bond percolation of Cayley graphs, and random walks on cocompact Fuchsian groups., Comment: This article overlaps the (almost twice as long) preprint arXiv:1710.00733 which will remain unpublished. Compared with said preprint the results on hyperbolic Poisson-Delaunay random walks have been removed, the exposition of the abstract formula for speed has been improved, and new applications of it are given
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- 2019
289. Placental single cell transcriptomics: Opportunities for endocrine disrupting chemical toxicology
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Elkin, Elana R., Campbell, Kyle A., Lapehn, Samantha, Harris, Sean M., Padmanabhan, Vasantha, Bakulski, Kelly M., and Paquette, Alison G.
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- 2023
- Full Text
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290. Collaboration and Partnership in a 5-Level Engagement Framework for Diabetic Foot Ulcer Management: A Patient-oriented Scoping Review
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Blanchette, Virginie, Todkar, Shweta, Brousseau-Foley, Magali, Rheault, Nathalie, Weisz, Tom, Poitras, Marie-Eve, Paquette, Jean-Sébastien, Tremblay, Marie-Claude, Costa, Idevânia G., Dogba, Maman Joyce, Giguere, Anik, de Mestral, Charles, and Légaré, France
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- 2023
- Full Text
- View/download PDF
291. Tech-equity in pediatric primary care: applying pandemic lessons in a post-public health emergency state
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Paquette, Erin
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- 2023
- Full Text
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292. Cultural safety involves new professional roles: A rapid review of interventions in Australia, the United States, Canada and New Zealand
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Tremblay, Marie-Claude, Olivier-D'Avignon, Genevieve, Garceau, Laurence, Echaquan, Sandro, Fletcher, Christopher, Leclerc, Anne-Marie, Poitras, Marie-Eve, Neashish, Eniko, Maillet, Lara, and Paquette, Jean-Sebastien
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- 2023
293. Mirror Descent Algorithms with Nearly Dimension-Independent Rates for Differentially-Private Stochastic Saddle-Point Problems extended abstract.
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Tomás González, Cristóbal Guzmán, and Courtney Paquette
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- 2024
294. Genetic continuity across a deeply divergent linguistic contact zone in North Maluku, Indonesia
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Wilder Jason A, Cox Murray P, Paquette Andrew M, Alford Regan, Satyagraha Ari W, Harahap Alida, and Sudoyo Herawati
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Genetics ,QH426-470 - Abstract
Abstract Background The islands of North Maluku, Indonesia occupy a central position in the major prehistoric dispersal streams that shaped the peoples of Island Southeast Asia and the Pacific. Within this region a linguistic contact zone exists where speakers of Papuan and Austronesian languages reside in close proximity. Here we use population genetic data to assess the extent to which North Maluku populations experienced admixture of Asian genetic material, and whether linguistic boundaries reflect genetic differentiation today. Results Autosomal and X-linked markers reveal overall Asian admixture of 67% in North Maluku, demonstrating a substantial contribution of genetic material into the region from Asia. We observe no evidence of population structure associated with ethnicity or language affiliation. Conclusions Our data support a model of widespread Asian admixture in North Maluku, likely mediated by the expansion of Austronesian-speaking peoples into the region during the mid Holocene. In North Maluku there is no genetic differentiation in terms of Austronesian- versus Papuan-speakers, suggesting extensive gene flow across linguistic boundaries. In a regional context, our results illuminate a major genetic divide at the Molucca Sea, between the islands of Sulawesi and North Maluku. West of this divide, populations exhibit predominantly Asian ancestry, with very little contribution of Papuan genetic material. East of the Molucca Sea, populations show diminished rates of Asian admixture and substantial persistence of Papuan genetic diversity.
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- 2011
- Full Text
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295. Increased FH-Risk-Score and Diabetes Are Cardiovascular Risk Equivalents in Heterozygous Familial Hypercholesterolemia
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Paquette, Martine, Cariou, Bertrand, Bernard, Sophie, Hegele, Robert A., Gallo, Antonio, Genest, Jacques, Trinder, Mark, Brunham, Liam R., Béliard, Sophie, and Baass, Alexis
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- 2024
- Full Text
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296. 327: A MULTICENTER RETROSPECTIVE ANALYSIS OF PEDIATRIC CLINICAL ETHICS CONSULTATIONS
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Drawbridge, Nicole, Sutyla, Ryan, Kingsley, Jenny, Vo, Holly, Barnett, Shannon, Hall, Erin, Kim, Daniel, Kolbe, Kelsey, Ray, Angela, Kolaitis, Irini, Derrington, Sabrina, Paquette, Erin, and Michelson, Kelly
- Published
- 2024
- Full Text
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297. 328: BEYOND RACE AND ETHNICITY: PREDICTORS OF ENGAGEMENT IN PEDIATRIC EMERGENCY & CRITICAL CARE RESEARCH
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Paquette, Erin, Barrera, Leonardo, Benedetti, Jillian, Jones, Mickayla, Guzman, Zecilly, Price, Heather, Heffernan, Marie, Alpern, Elizabeth, Frader, Joel, Shah, Seema, Ross, Lainie, Carnethon, Mercedes, Davis, Matthew, and Michelson, Kelly
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- 2024
- Full Text
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298. 326: PEDIATRIC INTENSIVE CARE UNIT APPROACHES TO CONFLICT HANDLING (PATCH): LEADERSHIP SURVEY RESULTS
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Olszewski, Aleksandra, Shah, Seema, Barrera, Leonardo, Castillo, Leopoldo, Kolaitis, Irini, Goodman, Denise, Basu, Rajit, and Paquette, Erin
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- 2024
- Full Text
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299. Examining public health practitioners’ perceptions and use of behavioural sciences to design health promotion interventions
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Ariane Bélanger-Gravel, Isidora Janezic, Sophie Desroches, Marie-Claude Paquette, Frédéric Therrien, Tracie Barnett, Kim L. Lavoie, and Lise Gauvin
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Behavioural sciences ,Public health ,Knowledge translation ,Qualitative study ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Behavioural sciences have been shown to support the development of more effective interventions aimed at promoting healthy lifestyles. However, the operationalization of this knowledge seems to be sub-optimal in public health. Effective knowledge transfer strategies are thus needed to optimize the use of knowledge from behavioural sciences in this field. To this end, the present study examined public health practitioners’ perceptions and use of theories and frameworks from behavioural sciences to design health promotion interventions. Methods This study adopted an exploratory qualitative design. Semi-structured interviews were conducted among 27 public health practitioners from across Canada to explore current intervention development processes, the extent to which they integrate theory and framework from behavioural sciences, and their perceptions regarding the use of this knowledge to inform intervention design. Practitioners from the public sector or non-profit/private organizations who were involved in the development of interventions aimed at promoting physical activity, healthy eating, or other healthy lifestyle habits (e.g., not smoking) were eligible to participate. Results Public health practitioners generally agreed that behaviour change is an important goal of public health interventions. On the other hand, behavioural science theories and frameworks did not appear to be fully integrated in the design of public health interventions. The main reasons were (1) a perceived lack of fit with current professional roles and tasks; (2) a greater reliance on experiential-produced knowledge rather than academic knowledge (mainly for tailoring interventions to local setting characteristics); (3) the presence of a fragmented knowledge base; (4) the belief that theories and frameworks require too much time and resources to be operationalized; and 4) the belief that using behavioural sciences might undermine partnership building. Conclusions This study provided valuable insights that may inform knowledge transfer strategies that could be optimally designed to support the integration of behavioural sciences theories and frameworks into public health practices.
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- 2023
- Full Text
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300. Sugar and Slavery, Family and Race: The Letters and Diary of Pierre Dessalles, Planter In Martinique, 1808–1856 ed. by Elborg Forster, Robert Forster (review)
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Paquette, Robert L.
- Published
- 2023
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