Keyword search (3,448 papers available)


Near-optimal learning of Banach-valued, high-dimensional functions via deep neural networks

Author(s): Adcock B; Brugiapaglia S; Dexter N; Moraga S;

The past decade has seen increasing interest in applying Deep Learning (DL) to Computational Science and Engineering (CSE). Driven by impressive results in applications such as computer vision, Uncertainty Quantification (UQ), genetics, simulations and imag...

Article GUID: 39454372
A unified stochastic SIR model driven by Lévy noise with time-dependency

Author(s): Easlick T; Sun W;

We propose a unified stochastic SIR model driven by Lévy noise. The model is structural enough to allow for time-dependency, nonlinearity, discontinuity, demography, and environmental disturbances. We present concise results on the existence and uniqueness ...

Article GUID: 39027117
Exactly Solvable Anharmonic Oscillator, Degenerate Orthogonal Polynomials and Painlevé II

Author(s): Bertola M; Chavez-Heredia E; Grava T;

Using WKB analysis, the paper addresses a conjecture of Shapiro and Tater on the similarity between two sets of points in the complex plane; on one side is the set the values of t ∈ C for which the spectrum of the quartic anharmonic oscillator in th...

Article GUID: 38983592
COVID-19 virtual patient cohort reveals immune mechanisms driving disease outcomes

Author(s): Jenner AL; Aogo RA; Alfonso S; Crowe V; Smith AP; Morel PA; Davis CL; Smith AM; Craig M;

To understand the diversity of immune responses to SARS-CoV-2 and distinguish features that predispose individuals to severe COVID-19, we developed a mechanistic, within-host mathematical model and virtual patient cohort. Our results indicate that virtual p...

Article GUID: 33442689
The infimum values of two probability functions for the Gamma distribution

Author(s): Sun P; Hu ZC; Sun W;

Let a, ß be positive real numbers and let Xα ,β be a Gamma random variable with shape parameter a and scale parameter ß. We study infimum values of the function (α ,β )↦ P{Xα ,β ≤ κ E[Xα ,β ]} for an...

Article GUID: 38261930
Complex localization mechanisms in networks of coupled oscillators: Two case studies

Author(s): Nicolaou ZG; Bramburger JJ;

Localized phenomena abound in nature and throughout the physical sciences. Some universal mechanisms for localization have been characterized, such as in the snaking bifurcations of localized steady states in pattern-forming partial differential equations. ...

Article GUID: 38252783
Children and chrono-exercise: Timing of physical activity on school and weekend days depends on sex and obesity status

Author(s): Reid RER; Henderson M; Barnett TA; Kakinami L; Tremblay A; Mathieu ME;

Recommendations for physical activity (PA) typically focus on frequency, intensity, duration, and type, but timing (chrono-exercise) is also important. The objective of this study is to describe when children are active on school and weekend days and explor...

Article GUID: 38083868
Medical Cannabis Use Among Canadian Veterans and Non-Veterans: A National Survey

Author(s): Valikhanova G; Kato Y; Fitzcharles MA; Ware M; Da Costa D; Lowensteyn I; Cheung HS; Grover S;...

Background: Medical cannabis (MC) is used by Canadian Veterans to manage a wide range of health issues. However, there is little information comparing the reasons for MC use and its perceived effec...

Article GUID: 37920683
Invariance, Encodings, and Generalization: Learning Identity Effects With Neural Networks

Author(s): Brugiapaglia S; Liu M; Tupper P;

Often in language and other areas of cognition, whether two components of an object are identical or not determines if it is well formed. We call such constraints identity effects. When developing a system to learn well-formedness from examples, it is easy ...

Article GUID: 35798322
Associations of neighborhood walkability with moderate to vigorous physical activity: an application of compositional data analysis comparing compositional and non-compositional approaches

Author(s): Bird M; Datta GD; Chinerman D; Kakinami L; Mathieu ME; Henderson M; Barnett TA;

Background: We compared the relation between neighborhood features and moderate to vigorous physical activity (MVPA) using linear regression analysis and the more novel compositional data analysis (CoDA). Compositional data analysis allows us to take the ti...

Article GUID: 35585542
Direct and indirect effects of roads on space use by jaguars in Brazil

Author(s): Cerqueira RC; de Rivera OR; Jaeger JAG; Grilo C;

Roads pose an imminent threat to wildlife directly through mortality and changes in individual behavior, and also indirectly through modification of the amount and configuration of wildlife habitat. However, few studies have addressed how these mechanisms i...

Article GUID: 34799617
Mental Health-Related Emergency Department Visits in Adolescents Before and During the COVID-19 Pandemic: A Multicentric Retrospective Study

Author(s): Chadi N; Spinoso-Di Piano C; Osmanlliu E; Gravel J; Drouin O;

Purpose: The purpose of this study was to compare pre/post-COVID-19 changes in mental health-related emergency department visits among adolescents. Methods: We conducted a retrospective analysis of all mental health-related emergency department visits in t...

Article GUID: 34462192
Personal Social Networks and Adiposity in Adolescents: A Feasibility Study

Author(s): Ybarra M; Barnett TA; Yu J; Van Hulst A; Drouin O; Kakinami L; Saint-Charles J; Henderson M;...

i>Background and Objective: Weight-related behaviors are determined by multiple individual and contextual factors, with recent evidence implicating personal social networks (PSNs). Greater understa...

Article GUID: 34264758
COVID-19 virtual patient cohort suggests immune mechanisms driving disease outcomes

Author(s): Jenner AL; Aogo RA; Alfonso S; Crowe V; Deng X; Smith AP; Morel PA; Davis CL; Smith AM; Craig M;...

To understand the diversity of immune responses to SARS-CoV-2 and distinguish features that predispose individuals to severe COVID-19, we developed a mechanistic, within-host mathematical model and...

Article GUID: 34260666
Diagonalization of the finite Hilbert transform on two adjacent intervals: the Riemann-Hilbert approach

Author(s): Bertola M; Blackstone E; Katsevich A; Tovbis A;

In this paper we study the spectra of bounded self-adjoint linear operators that are related to finite Hilbert transforms H L : L 2 ( [ b L , 0 ] ) → L 2 ( [ 0 , b R ] ) and H R : L 2 ( [ 0 , b R ] ) → L 2 ( [ b L , 0 ] ) . These operato...

Article GUID: 32684912
The Impairment of Number Transcoding Abilities in Individuals with Amnestic Mild Cognitive Impairment and Alzheimer Disease: Associations With Attentional and Executive Functions.

Author(s): Macoir J, Lafay A, Hudon C

Cogn Behav Neurol. 2020 Mar;33(1):33-44 Authors: Macoir J, Lafay A, Hudon C

Article GUID: 32132401
Diffusion dynamics on the coexistence subspace in a stochastic evolutionary game

Author(s): Popovic L; Peuckert L;

Frequency-dependent selection reflects the interaction between different species as they battle for limited resources in their environment. In a stochastic evolutionary game the species relative fitnesses guides the evolutionary dynamics with fluctuations d...

Article GUID: 32025789
Wigner functions from the two-dimensional wavelet group.

Author(s): Ali ST, Krasowska AE, Murenzi R

J Opt Soc Am A Opt Image Sci Vis. 2000 Dec;17(12):2277-87 Authors: Ali ST, Krasowska AE, Murenzi R

Article GUID: 11140488
Chaotic maps derived from trajectory data.

Author(s): Boyarsky A, Gora P

Chaos. 2002 Mar;12(1):42-48 Authors: Boyarsky A, Gora P

Article GUID: 12779531
A new hierarchy of integrable systems associated to Hurwitz spaces.

Author(s): Kokotov A, Korotkin D

Philos Trans A Math Phys Eng Sci. 2008 Mar 28;366(1867):1055-1088 Authors: Kokotov A, Korotkin D

Article GUID: 17588869
Periods of hyperelliptic integrals expressed in terms of theta-constants by means of Thomae formulae.

Author(s): Enolski V, Richter P

Philos Trans A Math Phys Eng Sci. 2008 Mar 28;366(1867):1005-24 Authors: Enolski V, Richter P

Article GUID: 17594965
Joint stationary moments of a two-island diffusion model of population subdivision.

Author(s): Kermany AR, Zhou X, Hickey DA

Theor Popul Biol. 2008 Nov;74(3):226-32 Authors: Kermany AR, Zhou X, Hickey DA

Article GUID: 18691608
Special comparison theorem for the Dirac equation.

Author(s): Hall RL

Phys Rev Lett. 2008 Aug 29;101(9):090401 Authors: Hall RL

Article GUID: 18851588
Noise reduction of cDNA microarray images using complex wavelets.

Author(s): Howlader T, Chaubey YP

IEEE Trans Image Process. 2010 Aug;19(8):1953-67 Authors: Howlader T, Chaubey YP

Article GUID: 20371406
A cluster randomized-controlled trial of a classroom-based drama workshop program to improve mental health outcomes among immigrant and refugee youth in special classes

Author(s): Rousseau C; Beauregard C; Daignault K; Petrakos H; Thombs BD; Steele R; Vasiliadis HM; Hechtman L;...

Objectives: The aim of this cluster randomized trial was to evaluate the effectiveness of a school-based theatre intervention program for immigrant and refugee youth in special classes for improvin...

Article GUID: 25127251
How spatial heterogeneity shapes multiscale biochemical reaction network dynamics.

Author(s): Pfaffelhuber P, Popovic L

J R Soc Interface. 2015 Mar 06;12(104):20141106 Authors: Pfaffelhuber P, Popovic L

Article GUID: 25652460
Topology and inference for Yule trees with multiple states.

Author(s): Popovic L, Rivas M

J Math Biol. 2016 11;73(5):1251-1291 Authors: Popovic L, Rivas M

Article GUID: 27009067
Title:COVID-19 virtual patient cohort reveals immune mechanisms driving disease outcomes
Authors:Jenner AL,  Aogo RA,  Alfonso S,  Crowe V,  Smith AP,  Morel PA,  Davis CL,  Smith AM,  Craig M, 
Link:https://pubmed.ncbi.nlm.nih.gov/33442689/
DOI:10.1101/2021.01.05.425420
Category:
PMID:33442689
Dept Affiliation: MATHSTATS
1 CHU Sainte-Justine Research Centre, Montréal, Québec, Canada.
2 Department of Mathematics and Statistics, Université de Montréal, Montréal, Québec, Canada.
3 Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee, USA.
4 Department of Physiology, McGill University, Montréal, Québec, Canada.
5 Department of Mathematics and Statistics, Concordia University, Montréal, Québec, Canada.
6 Department of Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
7 Natural Science Division, Pepperdine University, Malibu, California, USA.

Description:

To understand the diversity of immune responses to SARS-CoV-2 and distinguish features that predispose individuals to severe COVID-19, we developed a mechanistic, within-host mathematical model and virtual patient cohort. Our results indicate that virtual patients with low production rates of infected cell derived IFN subsequently experienced highly inflammatory disease phenotypes, compared to those with early and robust IFN responses. In these in silico patients, the maximum concentration of IL-6 was also a major predictor of CD8 + T cell depletion. Our analyses predicted that individuals with severe COVID-19 also have accelerated monocyte-to-macrophage differentiation that was mediated by increased IL-6 and reduced type I IFN signalling. Together, these findings identify biomarkers driving the development of severe COVID-19 and support early interventions aimed at reducing inflammation.

Author summary: Understanding of how the immune system responds to SARS-CoV-2 infections is critical for improving diagnostic and treatment approaches. Identifying which immune mechanisms lead to divergent outcomes can be clinically difficult, and experimental models and longitudinal data are only beginning to emerge. In response, we developed a mechanistic, mathematical and computational model of the immunopathology of COVID-19 calibrated to and validated against a broad set of experimental and clinical immunological data. To study the drivers of severe COVID-19, we used our model to expand a cohort of virtual patients, each with realistic disease dynamics. Our results identify key processes that regulate the immune response to SARS-CoV-2 infection in virtual patients and suggest viable therapeutic targets, underlining the importance of a rational approach to studying novel pathogens using intra-host models.