Publications

1351. Predictors of Loss of Infectivity Among Healthcare Workers with Primary and Recurrent SARS-CoV-2 infection: An Observational Cohort Study
Stefka Dzieciolowska
Yves Longtin
Hugues Charest
Tonya Roy
Judith Fafard
Inès Levade
Jean Longtin
Leighanne Parkes
Jasmin Villeneuve
Patrice Savard
Jacques Corbeil
Gaston De Serres
Abstract Background Factors associated with loss of infectivity in healthcare workers (HCWs) with COVID-19 are poorly understood. Understand… (see more)ing predictive factors could help optimize return-to-work criteria and minimize absenteeism. Methods Prospective observational cohort study of HCWs with COVID-19 conducted between Feb 20 2022 and March 6 2023 in 20 institutions in Montreal, Canada, with clinical/laboratory follow-up on Day 5, 7 and 10 of infection. Infectivity was determined by viral culture (Vero E6 cells) on nasopharyngeal swabs. Predictors of loss of infectivity were investigated by univariate and multivariate logistic regression. Results Overall, 121 participants (79.3% female, mean age 40 years) were recruited. Most (n=107, 88.4%) had received ≥3 vaccines and 20 (16.5%) had a history of prior COVID-19. The proportion of HCWs with a positive viral culture decreased from 71.9% on day 5 of infection to 18.2% on day 10. The proportion of HCWs with a positive RT-PCR decreased from 93.3% (112/120) on day 5 (median Ct value, 23.4 [IQR, 20.6-27.9]) to 61.2% (74/120) on day 10 (median Ct value, 32.5 [IQR, 28.5 to undetectable]). Rapid antigen detection test (RADT) positivity decreased from 81.5% on day 5 to 34.2% on day 10. Participants with recurrent COVID-19 had lower likelihood of infectivity at each visit (OR on day 5, 0.14; 95% CI 0.05-0.40; p 0.001; OR on day 7, 0.04; 95% CI, 0.01-0.33; p=0.003) and none were infective on day 10 (p=0.02). At each visit, recurrent cases had higher median RT-PCR Ct values than primary infections (p 0.03) and were more likely to have a negative RADT result (p 0.01). By multivariate analysis, ongoing infectivity was associated with a RT-PCR Ct value 23 (adjusted OR [aOR] on day 5, 22.75; p 0.001; aOR on Day 7, 182.30; p 0.001; and aOR on Day 10; 24.71; p=0.02). A history of previous COVID-19 was associated with a lower probability of infectivity on Day 5 (aOR, 0.005; p=0.003). By contrast, symptom improvement (including fever) and RADT result were not independent predictors of loss of infectivity. Conclusion A lower RT-PCR Ct value is associated with ongoing infectivity, whereas COVID-19 reinfection is a predictor of loss of infectivity. These findings could help optimize return-to-work algorithms. Disclosures All Authors: No reported disclosures
2023-11-27
Open Forum Infectious Diseases (published)
doi.org
Author Correction: 30×30 biodiversity gains rely on national coordination
Isaac Eckert
Andrea Brown
Dominique Caron
Federico Riva
Laura J. Pollock
2023-11-27
Nature Communications (published)
doi.org
Exploring the multidimensional nature of repetitive and restricted behaviors and interests (RRBI) in autism: neuroanatomical correlates and clinical implications
Aline Lefebvre
Nicolas Traut
Amandine Pedoux
Anna Maruani
Anita Beggiato
Monique Elmaleh
David Germanaud
Anouck Amestoy
Myriam Ly‐Le Moal
Christopher H. Chatham
Lorraine Murtagh
Manuel Bouvard
Marianne Alisson
Marion Leboyer
Thomas Bourgeron
Roberto Toro
Guillaume Dumas
Clara A. Moreau
Richard Delorme
2023-11-27
Molecular Autism (published)
doi.org
Exploring the multidimensional nature of repetitive and restricted behaviors and interests (RRBI) in autism: neuroanatomical correlates and clinical implications
Aline Lefebvre
Nicolas Traut
Amandine Pedoux
Anna Maruani
Anita Beggiato
Monique Elmaleh
David Germanaud
Anouck Amestoy
Myriam Ly‐Le Moal
Christopher H. Chatham
Lorraine Murtagh
Manuel Bouvard
Marianne Alisson
Marion Leboyer
Thomas Bourgeron
Roberto Toro
Guillaume Dumas
Clara A. Moreau
Richard Delorme
2023-11-27
Molecular Autism (published)
doi.org
Exploring the multidimensional nature of repetitive and restricted behaviors and interests (RRBI) in autism: neuroanatomical correlates and clinical implications
Aline Lefebvre
Nicolas Traut
Amandine Pedoux
Anna Maruani
Anita Beggiato
Monique Elmaleh
David Germanaud
Anouck Amestoy
Myriam Ly‐Le Moal
Christopher H. Chatham
Lorraine Murtagh
Manuel Bouvard
Marianne Alisson
Marion Leboyer
Thomas Bourgeron
Roberto Toro
Guillaume Dumas
Clara A. Moreau
Richard Delorme
2023-11-27
Molecular Autism (published)
doi.org
scGeneRythm: Using Neural Networks and Fourier Transformation to Cluster Genes by Time-Frequency Patterns in Single-Cell Data
Yiming Jia
Hao Wu
Jun Ding
2023-11-27
bioRxiv (preprint)
doi.org
The search for the lost attractor
Mario Pasquato
Syphax Haddad
Pierfrancesco Di Cintio
Alexandre Adam
Pablo Lemos
No'e Dia
Mircea Petrache
Ugo Niccolo Di Carlo
Alessandro A. Trani
Laurence Perreault-Levasseur
Yashar Hezaveh
2023-11-27
ArXiv (preprint)
arxiv.org
arxiv.org
Hessian Aware Low-Rank Perturbation for Order-Robust Continual Learning
Jiaqi Li
Rui Wang
Yuanhao Lai
Changjian Shui
Sabyasachi Sahoo
Charles Ling
Shichun Yang
Boyu Wang
Christian Gagné
Fan Zhou
2023-11-26
ArXiv (preprint)
doi.org
arxiv.org
Hessian Aware Low-Rank Perturbation for Order-Robust Continual Learning
Jiaqi Li
Rui Wang
Yuanhao Lai
Changjian Shui
Sabyasachi Sahoo
Charles Ling
Shichun Yang
Boyu Wang
Christian Gagné
Fan Zhou
2023-11-26
ArXiv (preprint)
doi.org
arxiv.org
Unlearning via Sparse Representations
Vedant Shah
Frederik Träuble
Ashish Malik
Hugo Larochelle
Michael Curtis Mozer
Sanjeev Arora
Yoshua Bengio
Anirudh Goyal
Machine \emph{unlearning}, which involves erasing knowledge about a \emph{forget set} from a trained model, can prove to be costly and infea… (see more)sible by existing techniques. We propose a nearly compute-free zero-shot unlearning technique based on a discrete representational bottleneck. We show that the proposed technique efficiently unlearns the forget set and incurs negligible damage to the model's performance on the rest of the data set. We evaluate the proposed technique on the problem of \textit{class unlearning} using three datasets: CIFAR-10, CIFAR-100, and LACUNA-100. We compare the proposed technique to SCRUB, a state-of-the-art approach which uses knowledge distillation for unlearning. Across all three datasets, the proposed technique performs as well as, if not better than SCRUB while incurring almost no computational cost.
2023-11-26
ArXiv (preprint)
doi.org
arxiv.org
Mitigating Biases with Diverse Ensembles and Diffusion Models
Luca Scimeca
Alexander Rubinstein
Damien Teney
Seong Joon Oh
Armand Mihai Nicolicioiu
Yoshua Bengio
Spurious correlations in the data, where multiple cues are predictive of the target labels, often lead to a phenomenon known as shortcut lea… (see more)rning, where a model relies on erroneous, easy-to-learn cues while ignoring reliable ones. In this work, we propose an ensemble diversification framework exploiting Diffusion Probabilistic Models (DPMs) to mitigate this form of bias. We show that at particular training intervals, DPMs can generate images with novel feature combinations, even when trained on samples displaying correlated input features. We leverage this crucial property to generate synthetic counterfactuals to increase model diversity via ensemble disagreement. We show that DPM-guided diversification is sufficient to remove dependence on primary shortcut cues, without a need for additional supervised signals. We further empirically quantify its efficacy on several diversification objectives, and finally show improved generalization and diversification performance on par with prior work that relies on auxiliary data collection.
2023-11-23
ArXiv (preprint)
arxiv.org
arxiv.org
Propositional Logics for the Lawvere Quantale
Giorgio Bacci
Radu Mardare
Prakash Panangaden
Gordon Plotkin
2023-11-23
Electronic Notes in Theoretical Informatics and Computer Science (published)
doi.org
arxiv.org