Publications

2025

• Kinetic theory and moment models of electrons in a reactive weakly-ionized non-equilibrium plasma
  
  • Laguna Alejandro Alvarez
  • Pichard Teddy
  Kinetic and Related Models, AIMS, 2025. <div><p>We study the electrons in a multi-component weakly-ionized plasma with an external electric field under conditions that are far from thermodynamic equilibrium, representative of a gas discharge plasma. Our starting point is the generalized Boltzmann equation with elastic, inelastic and reactive collisions. We perform a dimensional analysis of the equation and an asymptotic analysis of the collision operators for small electron-to-atom mass ratios and small ionization levels. The dimensional analysis leads to a diffusive scaling for the electron transport. We perform a Hilbert expansion of the electron distribution function that, in the asymptotic limit, results in a reduced model characterized by a spherically symmetric distribution function in the velocity space with a small anisotropic perturbation. We show that the spherical-harmonics expansion model, widely used in low-temperature plasmas, is a particular case of our approach. We approximate the solution of our kinetic model with a truncated moment hierarchy. Finally, we study the moment problem for a particular case: a Langevin collision (equivalent to Maxwell molecules) for the electron-gas elastic collisions. The resulting Stieltjes moment problem leads to an advection-diffusion-reaction system of equations that is approximated with two different closures: the quadrature method of moments and a Hermitian moment closure. A special focus is given along the derivations and approximations to the notion of entropy dissipation.</p></div> (10.3934/krm.2025007)
  DOI : 10.3934/krm.2025007
• Macroscopic limit from a structured population model to the Kirkpatrick-Barton model
  
  • Raoul Gaël
  Bulletin des Sciences Mathématiques, Elsevier, 2025, 205, pp.103697. We consider an ecology model in which the population is structured by a spatial variable and a phenotypic trait. The model combines a parabolic operator on the spatial variable with a kinetic operator on the trait variable. We prove the existence of solutions to that model, and show that these solutions are unique. The kinetic operator present in the model, that represents the effect of sexual reproductions, satisfies a Tanaka-type inequality: it implies a contraction of the Wasserstein distance in the space of phenotypic traits. We combine this contraction argument with parabolic estimates controlling the spatial regularity of solutions to prove the convergence of the population size and the mean phenotypic trait to solutions of the Kirkpatrick-Barton model, which is a well-established model in evolutionary ecology. Specifically, at high reproductive rates, we provide explicit convergence estimates for the moments of solutions of the kinetic model. (10.48550/arXiv.1706.04094)
  DOI : 10.48550/arXiv.1706.04094
• An analysis of the noise schedule for score-based generative models
  
  • Strasman Stanislas
  • Ocello Antonio
  • Boyer Claire
  • Le Corff Sylvain
  • Lemaire Vincent
  Transactions on Machine Learning Research, [Amherst Massachusetts]: OpenReview.net, 2022, 2025. Score-based generative models (SGMs) aim at estimating a target data distribution by learning score functions using only noise-perturbed samples from the target. Recent literature has focused extensively on assessing the error between the target and estimated distributions, gauging the generative quality through the Kullback-Leibler (KL) divergence and Wasserstein distances. Under mild assumptions on the data distribution, we establish an upper bound for the KL divergence between the target and the estimated distributions, explicitly depending on any time-dependent noise schedule. Under additional regularity assumptions, taking advantage of favorable underlying contraction mechanisms, we provide a tighter error bound in Wasserstein distance compared to state-of-the-art results. In addition to being tractable, this upper bound jointly incorporates properties of the target distribution and SGM hyperparameters that need to be tuned during training. Finally, we illustrate these bounds through numerical experiments using simulated and CIFAR-10 datasets, identifying an optimal range of noise schedules within a parametric family.
• Development of a rabbit model of uterine rupture after caesarean section, Histological, biomechanical and polarimetric analysis of the uterine tissue
  
  • Debras Elodie
  • Maudot Constance
  • Allain Jean-Marc
  • Pierangelo Angelo
  • Courilleau Aymeric
  • Rivière Julie
  • Dahirel Michèle
  • Richard Christophe
  • Gelin Valérie
  • Morin Gwendoline
  • Capmas Perrine
  • Chavatte-Palmer Pascale
  Reproduction & Fertility, Bioscientifica Ltd, 2025, 6 (4), pp.e-250018. Uterine rupture is a major complication of caesarean section (CS) associated with a high foetal and maternal morbidity. The objective is to develop an in-vivo model of uterus healing and rupture after CS in order to analyse histological phenomena controlling scarring tissue development and potential cause of defects. Eighteen pregnant primiparous female rabbits were bred naturally. At caesarean, after 28 days of gestation, foetuses were either extracted through a longitudinal incision in one of the uterine horns (“CS horn”) or via a short incision at the tip of the contralateral horn (“control horn”). The uterine horns were sutured by single layer, all by the same surgeon. They were mated again 14 days later and euthanized at G28. Genital tracts were collected for histological, biomechanical and polarimetric analyses. Macroscopically, 2/18 presented a dehiscence and 1/18 a spontaneous rupture. The mean thickness of the scarred area was significantly lower 0.9 mm [0.7-1.4] that the non-scarring area on CS horns 2.2 [1.6-2.3] or control horns 2 [1.5-2.3] (p&lt;0.0001). The scar zone was statistically more fibrous (p&lt;0.0001), containing fewer vessels (p=0.03) and oestrogen (p&lt;0.001) and progesterone receptors (p&lt;0.0001). After balloon inflation, ruptured occurred in the scar zone in 8 out of 17 cases (47%). Polarimetry revealed that the scar zone was statistically inhomogeneous (73%). Multifactorial analysis allowed to identify groups with poor uterine healing and less resistant to rupture (balloon inflation) mostly in case of thin myometrium in the scar and a group with strong resistant to rupture and correct healing characteristics. Lay summary Caesarean section rates are rising across the world. When a caesarean section is carried out, it can lead to scarring on the uterus that can affect its resistance to pressure. During the next pregnancy, the uterus can tear, increasing risks to the mother and baby. We carried out caesarean sections in a rabbit, allowing us to analyse the scar on the uterus, the healing and tissue resistance. The scarred part of the uterus was statistically thinner, more fibrous and contained fewer vessels and hormone receptors than the area without scarring. Under similar conditions, poor healing was observed in some animals, reducing resistance in following pregnancies. These results suggest that individual and genetic factor have an effect on healing after a caesarean section. This study may enable us to improve our knowledge and management care for patients who have a caesarean section in order to reduce complications. (10.1530/raf-25-0018)
  DOI : 10.1530/raf-25-0018
• Solving inverse source wave problem from Carleman estimates to observer design
  
  • Boulakia Muriel
  • de Buhan Maya
  • Delaunay Tiphaine
  • Imperiale Sébastien
  • Moireau Philippe
  Mathematical Control and Related Fields, AIMS, 2025. In this work, we are interested by the identification in a wave equation of a space dependent source term multiplied by a known time and space dependent function, from internal velocity or field measurements. The first part of the work consists in proving stability inequalities associated with this inverse problem from adapted Carleman estimates. Then, we present a sequential reconstruction strategy which is proved to be equivalent to the minimization of a cost functional with Tikhonov regularization. Based on the obtained stability estimates, the reconstruction error is evaluated with respect to the noise intensity. Finally, the proposed method is illustrated with numerical simulations, both in the case of regular source terms and of piecewise constant source terms. (10.3934/mcrf.2025007)
  DOI : 10.3934/mcrf.2025007
• From Stochastic Zakharov System to Multiplicative Stochastic Nonlinear Schrödinger Equation
  
  • Barrué Grégoire
  • de Bouard Anne
  • Debussche Arnaud
  Stochastics and Partial Differential Equations: Analysis and Computations, Springer US, 2025, pp.1-40. We study the convergence of a Zakharov system driven by a time white noise, colored in space, to a multiplicative stochastic nonlinear Schrödinger equation, as the ion-sound speed tends to infinity. In the absence of noise, the conservation of energy gives bounds on the solutions, but this evolution becomes singular in the presence of the noise. To overcome this difficulty, we show that the problem may be recasted in the diffusion-approximation framework, and make use of the perturbed test-function method. We also obtain convergence in probability. The result is limited to dimension one, to avoid too much technicalities. As a prerequisite, we prove the existence and uniqueness of regular solutions of the stochastic Zakharov system.
• Long time behavior of a degenerate stochastic system modeling the response of a population face to environmental impacts
  
  • Collet Pierre
  • Ecotière Claire
  • Méléard Sylvie
  Electronic Communications in Probability, Institute of Mathematical Statistics (IMS), 2025, 30 (none). We study the asymptotics of a two-dimensional stochastic differential system with a degenerate diffusion matrix. This system describes the dynamics of a population where individuals contribute to the degradation of their environment through two different behaviors. We exploit the almost one-dimensional form of the dynamical system to compute explicitly the Freidlin-Wentzell action functional. That allows to give conditions under which the small noise regime of the invariant measure is concentrated around the equilibrium of the dynamical system having the smallest diffusion coefficient. (10.1214/24-ECP650)
  DOI : 10.1214/24-ECP650
• Adaptive Destruction Processes for Diffusion Samplers
  
  • Gritsaev Timofei
  • Morozov Nikita
  • Tamogashev Kirill
  • Tiapkin Daniil
  • Samsonov Sergey
  • Naumov Alexey
  • Vetrov Dmitry
  • Malkin Nikolay
  , 2025. This paper explores the challenges and benefits of a trainable destruction process in diffusion samplers -- diffusion-based generative models trained to sample an unnormalised density without access to data samples. Contrary to the majority of work that views diffusion samplers as approximations to an underlying continuous-time model, we view diffusion models as discrete-time policies trained to produce samples in very few generation steps. We propose to trade some of the elegance of the underlying theory for flexibility in the definition of the generative and destruction policies. In particular, we decouple the generation and destruction variances, enabling both transition kernels to be learned as unconstrained Gaussian densities. We show that, when the number of steps is limited, training both generation and destruction processes results in faster convergence and improved sampling quality on various benchmarks. Through a robust ablation study, we investigate the design choices necessary to facilitate stable training. Finally, we show the scalability of our approach through experiments on GAN latent space sampling for conditional image generation. (10.48550/arXiv.2506.01541)
  DOI : 10.48550/arXiv.2506.01541
• Inverse scattering for the multipoint potentials of Bethe-Peierls-Thomas-Fermi type
  
  • Kuo Pei-Cheng
  • Novikov Roman
  Inverse Problems, IOP Publishing, 2025, 41 (6), pp.065021. <div><p>We consider the Schrödinger equation with a multipoint potential of the Bethe-Peierls-Thomas-Fermi type. We show that such a potential in dimension d = 2 or d = 3 is uniquely determined by its scattering amplitude at a fixed positive energy. Moreover, we show that there is no non-zero potential of this type with zero scattering amplitude at a fixed positive energy and a fixed incident direction. Nevertheless, we also show that a multipoint potential of this type is not uniquely determined by its scattering amplitude at a positive energy E and a fixed incident direction. Our proofs also contribute to the theory of inverse source problem for the Helmholtz equation with multipoint source.</p></div> (10.1088/1361-6420/ade282)
  DOI : 10.1088/1361-6420/ade282
• Byzantine-Robust Gossip: Insights from a Dual Approach
  
  • Gaucher Renaud
  • Dieuleveut Aymeric
  • Hendrikx Hadrien
  , 2025. Distributed learning has many computational benefits but is vulnerable to attacks from a subset of devices transmitting incorrect information. This paper investigates Byzantine resilient algorithms in a decentralized setting, where devices communicate directly in a peer-to-peer manner within a communication network. We leverage the so-called dual approach for decentralized optimization and propose a Byzantine-robust algorithm. We provide convergence guarantees in the average consensus subcase, discuss the potential of the dual approach beyond this subcase, and re-interpret existing algorithms using the dual framework. Lastly, we experimentally show the soundness of our method.
• Detecting random bifurcations via rigorous enclosures of large deviations rate functions
  
  • Blessing Alexandra
  • Blumenthal Alex
  • Breden Maxime
  • Engel Maximilian
  Physica D: Nonlinear Phenomena, Elsevier, 2025, 476, pp.134617. The main goal of this work is to provide a description of transitions from uniform to nonuniform snychronization in diffusions based on large deviation estimates for finite time Lyapunov exponents. These can be characterized in terms of moment Lyapunov exponents which are principal eigenvalues of the generator of the tilted (Feynman-Kac) semigroup. Using a computer assisted proof, we demonstrate how to determine these eigenvalues and investigate the rate function which is the Legendre-Fenchel transform of the moment Lyapunov function. We apply our results to two case studies: the pitchfork bifurcation and a two-dimensional toy model, also considering the transition to a positive asymptotic Lyapunov exponent. (10.1016/j.physd.2025.134617)
  DOI : 10.1016/j.physd.2025.134617
• Optimisation of space-time periodic eigenvalues
  
  • Bogosel Beniamin
  • Mazari Idriss
  • Nadin Grégoire
  Annali della Scuola Normale Superiore di Pisa. Classe di Scienze, Scuola Normale Superiore [1974-....], 2025. <div><p>The goal of this paper is to provide a qualitative analysis of the optimisation of space-time periodic principal eigenvalues. Namely, considering a fixed time horizon T and the d-dimensional torus T d , let, for any m ∈ L ∞ ((0, T ) × T d ), λ(m) be the principal eigenvalue of the operator ∂t -∆ -m endowed with (time-space) periodic boundary conditions. The main question we set out to answer is the following: how to choose m so as to minimise λ(m)? This question stems from population dynamics. We prove that in several cases it is always beneficial to rearrange m with respect to time in a symmetric way, which is the first comparison result for the rearrangement in time of parabolic equations. Furthermore, we investigate the validity (or lack thereof) of Talenti inequalities for the rearrangement in time of parabolic equations. The numerical simulations which illustrate our results were obtained by developing a framework within which it is possible to optimise criteria with respect to functions having a prescribed rearrangement (or distribution function).</p></div> (10.2422/2036-2145.202501_012)
  DOI : 10.2422/2036-2145.202501_012
• Efficient treatment of the model error in the calibration of computer codes: the Complete Maximum a Posteriori method
  
  • Kahol Omar
  • Congedo Pietro Marco
  • Le Maitre Olivier
  • Denimal Goy Enora
  International Journal for Uncertainty Quantification, Begell House Publishers, 2025. <div><p>Computer models are widely used for the prediction of complex physical phenomena. Based on observations of these physical phenomena, it is possible to calibrate the model parameters. In most cases, such computer models are mis-specified, and the calibration process must be improved by including a model error term. The model error hyperparameters are, however, rarely learned jointly with the model parameters to reduce the dimensionality of the problem. Sequential and non-sequential approaches have been introduced to estimate the hyperparameters. The former, such as the Kennedy and O'Hagan (KOH) framework, estimates the model error hyperparameters before calibrating the model parameters. The latter, such as the Full Maximum a Posteriori (FMP), introduces a functional dependence between the model parameters and the model error hyperparameters. Despite being more reliable in some cases (bimodality e.g.), the FMP method still fails to estimate correctly the posterior distribution shape. This work proposes a new methodology for treating the model error term in computer code calibration. It builds upon the KOH and FMP framework. Called the Complete Maximum a Posteriori (CMP) method, it provides a closed-form expression for the marginalization integral over the model error hyperparameters, significantly reducing the dimensionality of the calibration problem. Such expression re- lies on a set of assumptions that are more general and less stringent than the ones usually employed. The CMP method is applied to four examples of increasing complexity, from elementary to real fluid dynamics problems, including or not bimodality. Compared to the true reference solution and unlike the KOH and FMP, the CMP method correctly captures the shape of the posterior distribution, including all modes and their weights. Moreover, it provides an accurate estimate of the distribution tails</p></div> (10.1615/Int.J.UncertaintyQuantification.2025056317)
  DOI : 10.1615/Int.J.UncertaintyQuantification.2025056317
• Taking Advantage of Multiple Scattering for Optical Reflection Tomography
  
  • Wasik Thomas
  • Barolle Victor
  • Aubry Alexandre
  • Garnier Josselin
  , 2025. <div><p>Optical Diffraction Tomography (ODT) is a powerful non-invasive imaging technique widely used in biological and medical applications. While significant progress has been made in transmission configuration, reflection ODT remains challenging due to the ill-posed nature of the inverse problem. We present a novel optimization algorithm for 3D refractive index (RI) reconstruction in reflection-mode microscopy. Our method takes advantage of the multiply-scattered waves that are reflected by uncontrolled background structures and that illuminate the foreground RI from behind. It tackles the ill-posed nature of the problem using weighted time loss, positivity constraints and Total Variation regularization. We have validated our method with data generated by detailed 2D and 3D simulations, demonstrating its performance under weak multiple scattering conditions and with simplified forward models used in the optimization routine for computational efficiency.</p><p>In addition, we highlight the need for multi-wavelength analysis and the use of regularization to ensure the reconstruction of the low spatial frequencies of the foreground RI.</p></div>
• Partial regularity for optimal transport with $p$-cost away from fixed points
  
  • Goldman Michael
  • Koch Lukas
  Proceedings of the American Mathematical Society, American Mathematical Society, 2025. We consider maps $T$ solving the optimal transport problem with a cost $c(x-y)$ modeled on the $p$-cost. For Hölder continuous marginals, we prove a $C^{1,\alpha}$-partial regularity result for $T$ in the set $\{\lvert T(x)-x\rvert&gt;0\}$.
• Probing the speckle to estimate the effective speed of sound, a first step towards quantitative ultrasound imaging
  
  • Garnier Josselin
  • Giovangigli Laure
  • Goepfert Quentin
  • Millien Pierre
  Inverse Problems and Imaging, AIMS American Institute of Mathematical Sciences, 2025 (1930-8337). <div><p>In this paper, we present a mathematical model and analysis for a new experimental method [Bureau and al., arXiv:2409.13901, 2024] for effective sound velocity estimation in medical ultrasound imaging. We perform a detailed analysis of the point spread function of a medical ultrasound imaging system when there is a mismatch between the effective sound speed in the medium and the one used in the backpropagation imaging functional. Based on this analysis, an estimator for the speed of sound error is introduced. Using recent results on stochastic homogenization of the Helmholtz equation, we provide a representation formula for the field scattered by a random multi-scale medium (whose acoustic behavior is similar to a biological tissue) in the time-harmonic regime. We then prove that statistical moments of the imaging function can be accessed from data collected with only one realization of the medium. We show that it is possible to locally extract the point spread function from an image constituted only of speckle and build an estimator for the effective sound velocity in the micro-structured medium. Some numerical illustrations are presented at the end of the paper.</p></div> (10.3934/ipi.2026001)
  DOI : 10.3934/ipi.2026001
• Signature volatility models: pricing and hedging with Fourier
  
  • Abi Jaber Eduardo
  • Gérard Louis-Amand
  SIAM Journal on Financial Mathematics, Society for Industrial and Applied Mathematics, 2025, 16 (2). We consider a stochastic volatility model where the dynamics of the volatility are given by a possibly infinite linear combination of the elements of the time extended signature of a Brownian motion. First, we show that the model is remarkably universal, as it includes, but is not limited to, the celebrated Stein-Stein, Bergomi, and Heston models, together with some path-dependent variants. Second, we derive the joint characteristic functional of the log-price and integrated variance provided that some infinitedimensional extended tensor algebra valued Riccati equation admits a solution. This allows us to price and (quadratically) hedge certain European and path-dependent options using Fourier inversion techniques. We highlight the efficiency and accuracy of these Fourier techniques in a comprehensive numerical study. (10.1137/24M1636952)
  DOI : 10.1137/24M1636952
• Crediting football players for creating dangerous actions in an unbiased way: the generation of threat (GoT) indices
  
  • Baouan Ali
  • Coustou Sebastien
  • Lacome Mathieu
  • Pulido Sergio
  • Rosenbaum Mathieu
  Journal of Quantitative Analysis in Sports, De Gruyter, 2025. We introduce an innovative methodology to identify football players at the origin of threatening actions in a team. In our framework, a threat is defined as entering the opposing team's danger area. We investigate the timing of threat events and ball touches of players, and capture their correlation using Hawkes processes. Our model-based approach allows us to evaluate a player's ability to create danger both directly and through interactions with teammates. We define a new index, called Generation of Threat (GoT), that measures in an unbiased way the contribution of a player to threat generation. For illustration, we present a detailed analysis of Chelsea's 2016-2017 season, with a standout performance from Eden Hazard. We are able to credit each player for his involvement in danger creation and determine the main circuits leading to threat. In the same spirit, we investigate the danger generation process of Stade Rennais in the 2021-2022 season. Furthermore, we establish a comprehensive ranking of Ligue 1 players based on their generated threat in the 2021-2022 season. Our analysis reveals surprising results, with players such as Jason Berthomier, Moses Simon and Frederic Guilbert among the top performers in the GoT rankings. We also present a ranking of Ligue 1 central defenders in terms of generation of threat and confirm the great performance of some center-back pairs, such as Nayef Aguerd and Warmed Omari.
• Learning homogenized hyperelastic behavior for topology optimization of lattice structures
  
  • Ribeiro Nogueira Breno
  • Allaire Grégoire
  , 2025. (10.5281/zenodo.14900138)
  DOI : 10.5281/zenodo.14900138
• Volume growth of Funk geometry and the flags of polytopes
  
  • Faifman Dmitry
  • Vernicos Constantin
  • Walsh Cormac
  Geometry and Topology, Mathematical Sciences Publishers, 2025, 29 (7), pp.3773-3811. We consider the Holmes-Thompson volume of balls in the Funk geometry on the interior of a convex domain. We conjecture that for a fixed radius, this volume is minimized when the domain is a simplex and the ball is centered at the barycenter, or in the centrally-symmetric case, when the domain is a Hanner polytope. This interpolates between Mahler's conjecture and Kalai's flag conjecture. We verify this conjecture for unconditional domains. For polytopal Funk geometries, we study the asymptotics of the volume of balls of large radius, and compute the two highest-order terms. The highest depends only on the combinatorics, namely on the number of flags. The second highest depends also on the geometry, and thus serves as a geometric analogue of the centro-affine area for polytopes. We then show that for any polytope, the second highest coefficient is minimized by a unique choice of center point, extending the notion of Santaló point. Finally, we show that, in dimension two, this coefficient, with respect to the minimal center point, is uniquely maximized by affine images of the regular polygon. (10.2140/gt.2025.29.3773)
  DOI : 10.2140/gt.2025.29.3773
• Finite elements for Wasserstein $W_p$ gradient flows
  
  • Cancès Clément
  • Matthes Daniel
  • Nabet Flore
  • Rott Eva-Maria
  ESAIM: Mathematical Modelling and Numerical Analysis, Société de Mathématiques Appliquées et Industrielles (SMAI) / EDP, 2025, 59 (3), pp.1565-1600. Wasserstein $\mathbb{W}_p$ gradient flows for nonlinear integral functionals of the density yield degenerate parabolic equations involving diffusion operators of $q$-Laplacian type, with $q$ being $p$'s conjugate exponent. We propose a finite element scheme building on conformal $\mathbb{P}_1$ Lagrange elements with mass lumping and a backward Euler time discretization strategy. Our scheme preserves mass and positivity while energy decays in time. Building on the theory of gradient flows in metric spaces, we further prove convergence towards a weak solution of the PDE that satisfies the energy dissipation equality. The analytical results are illustrated by numerical simulations. (10.1051/m2an/2025035)
  DOI : 10.1051/m2an/2025035
• A holographic uniqueness theorem for the two-dimensional Helmholtz equation
  
  • Nair Arjun
  • Novikov Roman
  The Journal of Geometric Analysis, Springer, 2025, 35 (4), pp.123. We consider a plane wave, a radiation solution, and the sum of these solutions (total solution) for the Helmholtz equation in an exterior region in $\mathbb R^2$. We consider a straight line in this region, such that the direction of propagation of the plane wave is not parallel to this line. We show that the radiation solution in the exterior region is uniquely determined by the intensity of the total solution on an interval of this line. In particular, this result solves one of the old mathematical questions of holography in its two-dimensional setting. Our proofs also contribute to the theory of the Karp expansion of radiation solutions in two dimensions. (10.1007/s12220-025-01949-x)
  DOI : 10.1007/s12220-025-01949-x
• Objective assessment of cardiac function using patient-specific biophysical modeling based on cardiovascular MRI combined with catheterization
  
  • Gusseva Maria
  • Castellanos Daniel Alexander
  • Veeram Reddy Surendranath
  • Hussain Tarique
  • Chapelle Dominique
  • Chabiniok Radomír
  AJP - Heart and Circulatory Physiology, American Physiological Society, 2025, 329 (5), pp.H118-H1191. Synthesizing multi-modality data, such as cardiovascular magnetic resonance imaging (MRI) combined with catheterization, into a single framework is challenging. Different acquisition systems are subjected to different measurement errors. Coupling clinical data with biomechanical models can assist in clinical data processing (e.g., model-based filtering of measurement noise) and quantify myocardial mechanics via metrics not readily available in the data, such as myocardial contractility. In this work we use a biomechanical modeling with the aim 1) to quantitatively compare model- and data-derived signals, and 2) to explore the potential of model-derived myocardial contractility and distal resistance of the circulation (Rd) to robustly quantify cardiovascular physiology. We used 51 ventricular catheterization pressure and cine MRI volume datasets from patients with single-ventricle physiology and left and right ventricles of patients with repaired tetralogy of Fallot. Ventricular time-varying elastance (TVE) metrics and linear regression were used to quantify the relationship between the maximum value of TVE (Emax) and maximum time derivative of ventricular pressure (max(dP/dt)) in data- and model-derived pressure and volume signals at p&lt;0.05. Pearson’s correlations were used to compare model-derived contractility and data-derived Emax and max(dP/dt), and model-derived Rd and data-derived vascular resistance. All data and model-derived linear regressions were significant (p&lt;0.05). Model-derived max(dP/dt) vs. data-derived Emax produced higher R2 than data-derived max(dP/dt) vs. data-derived Emax. Correlations demonstrated significant relationships between most data- and model-derived metrics. This work revealed the clinical value of biomechanical modeling to assist in clinical data processing by providing high-quality pressure and volume signals, and to quantify cardiovascular pathophysiology. (10.1152/ajpheart.00232.2025)
  DOI : 10.1152/ajpheart.00232.2025
• A hybrid approach for steady-state production optimization of a real oil and gas platform: Integrating physics-based models, machine learning techniques, and field monitoring signals
  
  • Trevisan Luca
  • Shokry Ahmed
  • Montini Marco
  • Moulines Eric
  • Zio Enrico
  Computers & Chemical Engineering, Elsevier, 2025, 203, pp.109320. (10.1016/J.COMPCHEMENG.2025.109320)
  DOI : 10.1016/J.COMPCHEMENG.2025.109320