Université du Québec à Montréal
  • Montréal, Québec, Canada
Recent publications
In this paper, we review the question of which action space is best suited for controlling a real biped robot in combination with Sim2Real training. Position control has been popular as it has been shown to be more sample efficient and intuitive to combine with other planning algorithms. However, for position control, gain tuning is required to achieve the best possible policy performance. We show that, instead, using a torque-based action space enables task-and-robot agnostic learning with less parameter tuning and mitigates the sim-to-reality gap by taking advantage of torque control's inherent compliance. Also, we accelerate the torque-based-policy training process by pre-training the policy to remain upright by compensating for gravity. The paper showcases the first successful sim-to-real transfer of a torque-based deep reinforcement learning policy on a real human-sized biped robot.
An improved understanding of behaviors reflecting acute pain in cats is a priority for feline welfare. The aim of this study was to create and validate a comprehensive ethogram of acute pain behaviors in cats that can discriminate painful versus non-painful individuals. An inventory of behaviors (ethogram) with their respective descriptors was created based on a literature review of PubMed, Web of Science and CAB Abstracts databases. The ethogram was divided into ten behavior categories that could be evaluated by duration and/or frequency: position in the cage, exploratory behaviors, activity, posture and body position, affective-emotional states, vocalization, playing (with an object), feeding, post-feeding and facial expressions/features. Thirty-six behaviors were analyzed independently by four veterinarians with postgraduate qualifications in feline medicine and/or behavior as (1) not relevant, (2) somewhat relevant, (3) quite relevant or (4) highly relevant and used for content (I-CVI) and face validity. Items with I-CVI scores > 0.67 were included. Twenty-four behaviors were included in the final ethogram. Thirteen items presented full agreement (i.e., I-CVI = 1): positioned in the back of the cage, no attention to surroundings, feigned sleep, grooming, attention to wound, crouched/hunched, abnormal gait, depressed, difficulty grasping food, head shaking, eye squinting, blepharospasm and lowered head position. Seven descriptors were reworded according to expert suggestions. The final ethogram provides a detailed description of acute pain behaviors in cats after content and face validity and can be applied to the characterization of different acute painful conditions in hospitalized cats.
Purpose Main concept (MC) analysis is a well-documented method of discourse analysis in adults with and without brain injury. This study aims to develop a MC checklist that is culturally and linguistically adapted for Canadian French speakers and examine its reliability. We also documented microstructural properties and provide a normative reference in persons not brain injured (PNBIs). Method Discourse samples from 43 PNBIs were collected. All participants completed the Cinderella story retell task twice. Manual transcription was performed for all samples. The 34 MCs for the Cinderella story retell task were adapted into Canadian French and used to score all transcripts. In addition, microstructural variables were extracted using Computerized Language Analysis (CLAN). Intraclass correlation coefficients were computed to assess interrater reliability for MC codes and microstructural variables. Test–retest reliability was assessed using intraclass correlations, Spearman's rho correlations, and the Wilcoxon signed-ranks test. Bland–Altman plots were used to examine the agreement of the discourse measures between the two sessions. Results The MC checklist for the Cinderella story retell task adapted for Canadian French speakers is provided. Good-to-excellent interrater reliability was obtained for most MC codes; however, reliability ranged from poor to excellent for the “inaccurate and incomplete” code. Microstructural variables demonstrated excellent interrater reliability. Test–retest reliability ranged from poor to excellent for all variables, with the majority falling between moderate and excellent. Bland–Altman plots illustrated the limits of agreement between test and retest. Conclusions This study provides the MC checklist for clinicians and researchers working with Canadian French speakers when assessing discourse with the Cinderella story retell task. It also addresses the gap in available psychometric data regarding test–retest reliability in PNBIs. Supplemental Material https://doi.org/10.23641/asha.24171087
Research summary Crackdowns are law enforcement strategies based on the principles of deterrence theory, which stipulates that offenders are rational actors who will refrain from crime if perceived risks are higher than perceived benefits. Studies have shown that the effects of police street drug crackdowns are mostly short termed and followed by considerable displacement. In the early 2010s, an important part of illicit drug trades moved online to cryptomarkets, and law enforcement agencies have responded by engaging in online drug crackdowns. In this study, we focus on the perceptions of dark web users in order to determine, from a qualitative “data‐driven” perspective, whether police online crackdowns may have a cyber‐deterrent effect by analyzing 1796 forum posts. Our results show that these events trigger psychological and practical consequences that participants claim to have a conditional, although minor, deterrent effect. In the majority of cases, dark web users claimed to engage in several forms of spatial and tactical displacement. Policy implications Our study suggests that police crackdowns on the dark web have limited, short‐term effectiveness in curbing illicit activities. It proposes that innovative policing approaches such as problem‐oriented policing and “pulling levers/focused deterrence” strategies, which involve identifying key actors and engaging with them, be potentially extended to the dark web. While this approach is promising, it emphasizes the need for further research to assess its efficacy in the online realm, as it is a largely uncharted territory for law enforcement.
Elementary public schools remain the most common venues for addressing children’s severe conduct problems. Nevertheless, very few longitudinal studies have examined association between receiving psychoeducational services for conduct problems in school and subsequent conduct problem severity. This study explored if psychoeducational service reception contributed to reduce conduct problems in a sample of 434 elementary school-aged boys and girls presenting a high level of conduct problems. The study used a repeated measures design at 12-month intervals, for 4 years. Information regarding the severity of children’s conduct problems and services was provided by parents and teachers. Latent Growth Modeling was used to identify a mean trajectory of conduct problems. Results revealed that psychoeducational services were associated with a decrease in conduct problems over time, but this association was only observed in boys. There was no association between service reception at study inception and the trajectory of conduct problems among girls. These results suggests that psychoeducational services are well suited to the difficulties of boys with conduct problems; however, they may call for a review of the services offered to girls in schools, both in terms of the detection of conduct problems in young girls, and in terms of their treatment options.
The widespread browning of northern lakes has been associated with long-term increases in dissolved organic carbon and color and should be linked to changes in surface water carbon dioxide, yet the long-term covariation in these three key carbon components of lake functioning remains to be assessed. We present long-term trends in dissolved organic carbon, color, and carbon dioxide from lakes, with generally positive but highly variable trends in organic carbon and a large degree of uncoupling with color and carbon dioxide. The highest rates of change in color and carbon dioxide were in lakes with greatest increasing dissolved organic carbon trends. Lakes with the lowest water retention times had greater increases and stronger coupling between all three parameters, coinciding with dominance of terrestrially derived carbon. These results suggest an uneven terrestrialization of northern lakes, where the increases and coupling in the three carbon components depends on hydrology and watershed connectivity.
This research aimed to conduct a systematic review of para powerlifting strength performance. The searches were conducted in three electronic databases: PubMed, Scopus, and SPORTDiscus. Intervention studies related to para powerlifting performance were included. The main information was extracted systematically, based on criteria established by the authors. The data on study design, sample size, participant’s characteristics (e. g. type of disability, sex, age, body weight, and height), training experience, assessment tools, physical performance criteria, and force-related outcomes were extracted and analyzed. The studies (n=9) describe factors related to biomechanics and performance. Outcomes revealed that the one-repetition maximum test is used as load prescription and that para powerlifting should work at high speeds and higher loads. Regarding technique, grip width with 1.5 biacromial distance provides a good lift and partial amplitude training as an alternative to training. There are no differences in total load and movement quality in the lumbar arched technique compared with the flat technique. As a monitoring method, repetitions in reserve scale was used for submaximal loads. Finally, our outcomes and discussion indicated strategies and techniques that can be used by para powerlifting coaches.
This paper presents a methodology developed at the Laboratory of Applied Research in Active Controls, Avionics, and Aeroservoelasticity to identify a performance model of the CF34-8C5B1 turbofan engine powering the CRJ-700 regional jet aircraft from simulated flight data using artificial neural networks (ANNs). For this purpose, a qualified virtual research simulator was used to conduct different types of flight tests and to collect engine data under a wide range of operating conditions. The collected data were then used to create a comprehensive database for the training of the ANN model. This process was performed using the Bayesian regularization algorithm available in the MATLAB Neural Networks Toolbox, followed by a study to identify the optimal network architecture, namely, the number of layers and the number of neurons. The validation of the methodology was accomplished by comparing the model predictions with a set of flight data collected with the flight simulator for different flight conditions and flight regimes including takeoff, climb, cruise, and descent. The results showed that the model was able to predict the engine performance in terms of fan speed, core speed, inlet turbine temperature, net thrust, and fuel flow with less than 5% relative error.
Babesia spp. are tick-borne parasites with a global distribution and diversity of vertebrate hosts. Over the next several decades, climate change is expected to impact humans, vectors, and vertebrate hosts and change the epidemiology of Babesia . Although humans are dead-end hosts for tick-transmitted Babesia , human-to-human transmission of Babesia spp. from transfusion of red blood cells and whole blood-derived platelet concentrates has been reported. In most patients, transfusion-transmitted Babesia (TTB) results in a moderate-to-severe illness. Currently, in North America, most cases of TTB have been described in the United States. TTB cases outside North America are rare, but case numbers may change over time with increased recognition of babesiosis and as the epidemiology of Babesia is impacted by climate change. Therefore, TTB is a concern of microbiologists working in blood operator settings, as well as in clinical settings where transfusion occurs. Microbiologists play an important role in deploying blood donor screening assays in Babesia endemic regions, identifying changing risks for Babesia in non-endemic areas, investigating recipients of blood products for TTB, and drafting TTB policies and guidelines. In this review, we provide an overview of the clinical presentation and epidemiology of TTB. We identify approaches and technologies to reduce the risk of collecting blood products from Babesia -infected donors and describe how investigations of TTB are undertaken. We also describe how microbiologists in Babesia non-endemic regions can assess for changing risks of TTB and decide when to focus on laboratory-test-based approaches or pathogen reduction to reduce TTB risk.
Background For oral cavity squamous cell carcinoma (OSCC), extent of extranodal extension (ENE) (minor, ≤2 mm; major, >2 mm) is differentially prognostic, whereas limitations exist with the 8th edition of American Joint Committee on Cancer/International Union Against Cancer TNM N‐classification (TNM‐8‐N). Methods Resected OSCC patients at four centers were included and extent of ENE was recorded. Thresholds for optimal overall survival (OS) discrimination of lymph node (LN) features were established. After dividing into training and validation sets, two new N‐classifications were created using 1) recursive partitioning analysis (RPA), and 2) adjusted hazard ratios (aHRs) and were ranked against TNM‐8‐N and two published proposals. Results A total of 1460 patients were included (pN0: 696; pN+: 764). Of the pN+ cases, 135 (18%) had bilateral/contralateral LNs; 126 (17%) and 244 (32%) had minor and major ENE, and two (0.3%) had LN(s) >6 cm without ENE (N3a). LN number (1 and >1 vs. 0: aHRs, 1.92 [95% confidence interval (CI), 1.44–2.55] and 3.21 [95% CI, 2.44–4.22]), size (>3 vs. ≤3 cm: aHR, 1.88 [95% CI, 1.44–2.45]), and ENE extent (major vs. minor: aHR, 1.40 [95% CI, 1.05–1.87]) were associated with OS, whereas presence of contralateral LNs was not (aHR, 1.05 [95% CI, 0.81–1.36]). The aHR proposal provided optimal performance with these changes to TNM‐8‐N: 1) stratification of ENE extent, 2) elimination of N2c and 6‐cm threshold, and 3) stratification of N2b by 3 cm threshold. Conclusion A new N‐classification improved staging performance compared to TNM‐8‐N, by stratifying by ENE extent, eliminating the old N2c category and the 6 cm threshold, and by stratifying multiple nodes by size.
The contraction of species range is one of the most significant symptoms of biodiversity loss worldwide. While anthropogenic activities and habitat alteration are major threats for several species, climate change should also be considered. For species at risk, differentiating the effects of human disturbances and climate change on past and current range transformations is an important step towards improved conservation strategies. We paired historical range maps with global atmospheric reanalyses from different sources to assess the potential effects of recent climate change on the observed northward contraction of the range of boreal populations of woodland caribou ( Rangifer tarandus caribou ) in Quebec (Canada) since 1850. We quantified these effects by highlighting the discrepancies between different southern limits of the caribou's range (used as references) observed in the past and reconstitutions obtained through the hindcasting of the climate conditions within which caribou are currently found. Hindcasted southern limits moved ~105 km north over time under all reanalysis datasets, a trend drastically different from the ~620 km reported for observed southern limits since 1850. The differences in latitudinal shift through time between the observed and hindcasted southern limits of distribution suggest that caribou range recession should have been only 17% of what has been observed since 1850 if recent climate change had been the only disturbance driver. This relatively limited impact of climate reinforces the scientific consensus stating that caribou range recession in Quebec is mainly caused by anthropogenic drivers (i.e. logging, development of the road network, agriculture, urbanization) that have modified the structure and composition of the forest over the past 160 years, paving the way for habitat‐mediated apparent competition and overharvesting. Our results also call for a reconsideration of past ranges in models aiming at projecting future distributions, especially for endangered species.
Introduction Artificial intelligence (AI) has the potential to improve efficiency and quality of care in healthcare settings. The lack of consideration for equity, diversity and inclusion (EDI) in the lifecycle of AI within healthcare settings may intensify social and health inequities, potentially causing harm to under-represented populations. This article describes the protocol for a scoping review of the literature relating to integration of EDI in the AI interventions within healthcare setting. The objective of the review is to evaluate what has been done on integrating EDI concepts, principles and practices in the lifecycles of AI interventions within healthcare settings. It also aims to explore which EDI concepts, principles and practices have been integrated into the design, development and implementation of AI in healthcare settings. Method and analysis The scoping review will be guided by the six-step methodological framework developed by Arksey and O’Malley supplemented by Levac et al, and Joanna Briggs Institute methodological framework for scoping reviews. Relevant literature will be identified by searching seven electronic databases in engineering/computer science and healthcare, and searching the reference lists and citations of studies that meet the inclusion criteria. Studies on AI in any healthcare and geographical settings, that have considered aspects of EDI, published in English and French between 2005 and present will be considered. Two reviewers will independently screen titles, abstracts and full-text articles according to inclusion criteria. We will conduct a thematic analysis and use a narrative description to describe the work. Any disagreements will be resolved through discussion with the third reviewer. Extracted data will be summarised and analysed to address aims of the scoping review. Reporting will follow the Preferred Reporting Items for Systematic Reviews and Meta-analyses Extension for Scoping Reviews. The study began in April 2022 and is expected to end in September 2023. The database initial searches resulted in 5,745 records when piloted in April 2022. Ethics and dissemination Ethical approval is not required. The study will map the available literature on EDI concepts, principles and practices in AI interventions within healthcare settings, highlight the significance of this context, and offer insights into the best practices for incorporating EDI into AI-based solutions in healthcare settings. The results will be disseminated through open-access peer-reviewed publications, conference presentations, social media and 2-day workshops with relevant stakeholders.
Childhood sexual abuse (CSA) is likely to have impacts on adult survivors' sexuality, particularly on their sexual self-concept. However, little is known about how survivors cope with CSA-related sexual impacts, including sexual self-concept impairments. Thus, this study aimed to examine the interplay between sexual self-concept and coping strategies in CSA survivors by (1) documenting the manifestations of their impaired sexual self-concepts; (2) identifying their strategies to cope with the sexual impacts of CSA; and (3) examining gender differences on sexual self-concept impairments and coping strategies. Content analysis was conducted on semi-structured interviews with 25 women and 26 men adult survivors of CSA recruited via social networks and victim support organizations. Analyses yielded three conceptual categories: (1) Developing an unconsolidated and unfavorable sexual self-concept following CSA; (2) Avoiding CSA-related sexual impacts and impaired sexual self-concept; (3) Approaching CSA-related sexual impacts with more authenticity. Men often managed their suffering and compensated for their impaired sexual self-concept by engaging in sexual dominance and over-investment, by accepting their sexual difficulties and relying on medication to overcome them. Women tended to restrict themselves and disconnect sexually to avoid suffering, complied with their partners' sexual demands out of a sense of duty, prioritized sexual intimacy over orgasm, and seek professional help. Interventions with survivors should promote the development of approach strategies to cope with sexual difficulties, including self-concept impairments, and foster sexual authenticity.
Background The prevalence, anatomical distribution, or nature of cutaneous, hair and oral mucosal abnormalities (CHMAs) in cattle is uncertain. Objectives To determine how often dairy cattle admitted to a veterinary teaching hospital (VTH) had CHMAs (except for foot and ear canal) on physical examination and if there was an age‐related difference. Animals Four hundred and thirty‐three cattle: cattle <3 months (n = 85), cattle 3 to 24 months (n = 73), and cattle >24 months (n = 275). Methods In this descriptive, observational, prospective study, CHMAs of dairy cattle admitted to the VTH of the Université de Montréal were recorded over 1 year. Prevalences were calculated. Dermatological examinations were performed within 48 hours of admission, according to a glossary. Chi‐square tests were used to compare prevalence between age groups. Results The 433 cattle were mostly females (97.5%) and of the Holstein breed (89.8%). The prevalence of cattle <3 months presenting with at least 1 identifiable CHMA was 65% (55/85). In cattle 3 to 24 months old, it was 90% (66/73), and in cattle >24 months, it was 99.3% (273/275). There were significant differences ( P < .001) between the prevalence of CHMAs localized on the ischia, ilia, stifles, hocks, carpi, flank, lateral neck, dorsal cervical, and cornual regions in cattle >24 months vs <3 months. Conclusions and Clinical Importance CHMAs were highly prevalent and age‐specific. Calluses on the carpi and hocks of cattle >24 months were the most common CHMAs.
Phylogenetic trees (i.e. evolutionary trees, additive trees or X-trees) play a key role in the processes of modeling and representing species evolution. Genome evolution of a given group of species is usually modeled by a species phylogenetic tree that represents the main patterns of vertical descent. However, the evolution of each gene is unique. It can be represented by its own gene tree which can differ substantially from a general species tree representation. Consensus trees and supertrees have been widely used in evolutionary studies to combine phylogenetic information contained in individual gene trees. Nevertheless, if the available gene trees are quite different from each other, then the resulting consensus tree or supertree can either include many unresolved subtrees corresponding to internal nodes of high degree or can simply be a star tree. This may happen if the available gene trees have been affected by different reticulate evolutionary events, such as horizontal gene transfer, hybridization or genetic recombination. Thus, the problem of inferring multiple alternative consensus trees or supertrees, using clustering, becomes relevant since it allows one to regroup in different clusters gene trees having similar evolutionary patterns (e.g. gene trees representing genes that have undergone the same horizontal gene transfer or recombination events). We critically review recent advances and methods in the field of phylogenetic tree clustering, discuss the methods’ mathematical properties, and describe the main advantages and limitations of multiple consensus tree and supertree approaches. In the application section, we show how the multiple supertree clustering approach can be used to cluster aaRS gene trees according to their evolutionary patterns.
The purpose of this article is to provide an explanation of the background behind a checklist that declares the laboratory methods used in a scientific study. It focuses primarily on implementing laboratory procedures to yield reliable results in basic semen examinations. While the World Health Organization (WHO) and international standards provide recommendations for basic semen examination, manuscripts submitted to Andrology frequently lack transparency regarding the specific techniques used. In addition, the terminology used for semen examination results often fails to provide a clear definition of the groups under study. Furthermore, the WHO's reference limits are often misinterpreted as strict boundaries between fertility and infertility. It is important to note that valid clinical andrological diagnoses and treatments cannot rely solely on semen examination results; they require proper laboratory procedures as a foundation for diagnosing and treating male patients. Therefore, scientific journals should promote the adoption of robust laboratory practices and an accurate definition of patient groups. A checklist can facilitate the design of high‐quality studies and the creation of informative publications. Further, it can help journals assess submitted manuscripts and improve the overall quality of their publications.
Small studies suggest that amiodarone is a weak inhibitor of cytochrome P450 (CYP) 2D6. Inhibition of CYP2D6 leads to increases in concentrations of drugs metabolized by the enzyme, such as metoprolol. Considering that both metoprolol and amiodar-one have β-adrenergic blocking properties and that the modest interaction between the two drugs would result in increased metoprolol concentrations, this could lead to a higher risk of bradycardia and atrioventricular block. The primary objective of this study was to evaluate whether metoprolol plasma concentrations collected at random timepoints from patients enrolled in the Montreal Heart Institute Hospital Cohort could be useful in identifying the modest pharmacokinetic interaction between amiodarone and metoprolol. We performed an analysis of a cross-sectional study, conducted as part of the Montreal Heart Institute Hospital Cohort. All participants were self-described "White" adults with metoprolol being a part of their daily pharmacotherapy regimen. Of the 999 patients being treated with metoprolol, 36 were also taking amiodarone. Amiodarone use was associated with higher metoprolol concentrations following adjustment for different covariates (p = .0132). Consistently, the association between amiodarone use and lower heart rate was apparent and significant after adjustment for all covariates under study (p = .0001). Our results highlight that single randomly collected blood samples can be leveraged to detect modest pharmacokinetic interactions.
Résumé Le comportement géomécanique du sel gemme a été largement étudié au fil des ans. Les différentes études expérimentales ont permis d'identifier des caractéristiques distinctives associées à une réponse inélastique non-linéaire qui est fonction du temps et de l'historique de chargement. Ces caractéristiques doivent être reproduites par les équations constitutives utilisées pour analyser la réponse du sel gemme autour des ouvertures souterraines. Dans cet article, un modèle constitutif relativement simple est introduit dans le code numérique FLAC et appliqué pour analyser le comportement différé d'excavations dans des mines de sel. Le modèle unifié en fluage et plasticité comprend une variable d“état interne avec une loi d”évolution qui induit un écrouissage progressif jusqu'à ce qu“un état stationnaire soit atteint. Des analyses numériques sont effectuées avec le modèle ISV-SH pour évaluer les paramètres du matériau et simuler la réponse d”une ouverture circulaire et d'excavations minières rectangulaires créées séquentiellement. Les résultats sont présentés et comparés à ceux obtenus avec l“équation bien connue de la loi de puissance de Norton, couramment utilisée dans l”ingénierie des mines de sel. Les résultats des calculs, présentés en termes de l’évolution des contraintes, des déformations et de vitesses de déformation, illustrent certains des aspects clés du comportement du sel gemme et ils mettent en évidence l“influence majeure de la loi de comportement utilisée pour les analyses numériques. L”approche de simulation proposée ici constitue une alternative pratique et flexible aux outils de modélisation basés sur le fluage stationnaire, souvent utilisés pour l“analyse des ouvertures souterraines dans les opérations d”extraction de sel gemme. ¹ Ceci est une traduction fournie par l'auteur du résumé en anglais.
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11,279 members
Martine Hébert
  • Department of Sexology
Olivier Germain
  • Department of Management
Francois Bedard
  • Department of Urban Studies and Tourism
Martin Blais
  • Department of Sexology
Tatiana Scorza
  • Department of Biological Sciences
CP 8888, succursale Centre-ville, H3C3P8, Montréal, Québec, Canada