Results 11 to 20 of about 134 (86)

Detail-preserving denoising of CT and MRI images via adaptive clustering and non-local means algorithm [PDF]

Scientific Reports
Medical imaging systems such as computed tomography (CT) and magnetic resonance imaging (MRI) are vital tools in clinical diagnosis and treatment planning.
Mohit Sharma, Ayush Dogra, Bhawna Goyal, Anita Gupta, Manob Jyoti Saikia   +4 more
doaj   +2 more sources

Sampling of non‐Gaussian Ensemble Average Propagators for the simulation of diffusion magnetic resonance images [PDF]

Magnetic Resonance in Medicine, Volume 95, Issue 2, Page 1255-1265, February 2026.
Abstract Purpose (a) To design a methodology for drawing random samples of any Ensemble Average Propagator (EAP) (b) to modify the KomaMRI simulator to accommodate them as realistic spin movements to simulate diffusion MRI (dMRI) and (c) to compare these simulations with those based on the Diffusion Tensor (DT) model.
Justino R. Rodríguez‐Galván, Pablo Villacorta‐Aylagas, Susana Merino‐Caviedes, Federico Simmross‐Wattenberg, Carlos Castillo‐Passi, Pablo Irarrazaval, Antonio Tristán‐Vega, Carlos Alberola‐López   +7 more
wiley   +2 more sources

Reducing thermal noise in high‐resolution quantitative magnetic resonance imaging rotating frame relaxation mapping of the human brain at 3 T [PDF]

NMR in Biomedicine, Volume 37, Issue 12, December 2024.
Whole‐brain rotating frame relaxation (RFR) mapping is generally implemented at moderate spatial resolutions. Our results showed that applying transform domain NORDIC (T‐NORDIC) before fitting improves the reliability of RFR parameter estimations, especially at higher spatial resolution, a benefit that can be critical for clinical applications ...
Sara Ponticorvo, Antonietta Canna, Steen Moeller, Mehmet Akcakaya, Gregory J. Metzger, Pavel Filip, Lynn E. Eberly, Shalom Michaeli, Silvia Mangia   +8 more
wiley   +2 more sources

Feasibility of strong diffusion encoding and fast readout using a plug‐and‐play head gradient insert at 7 T [PDF]

Magnetic Resonance in Medicine, Volume 94, Issue 5, Page 2304-2316, November 2025.
Purpose Diffusion weighting is achieved by the application of external field gradients typically for tens of milliseconds, during which the signal also substantially decays due to inherent T2 relaxation. Employing strong gradients will shorten the echo time (TE) and increase the signal‐to‐noise ratio.
G. C. Arends, E. Versteeg, A. De Luca, F. Marc, T. H. M. Roos, D. W. J. Klomp, M. Froeling, J. C. W. Siero, C. M. W. Tax   +8 more
wiley   +2 more sources

Compressed sensing reconstruction for high‐SNR, rapid dissolved 129Xe gas exchange MRI [PDF]

Magnetic Resonance in Medicine, Volume 93, Issue 2, Page 741-750, February 2025.
Abstract Purpose Three‐dimensional hyperpolarized 129Xe gas exchange imaging suffers from low SNR and long breath‐holds, which could be improved using compressed sensing (CS). The purpose of this work was to assess whether gas exchange ratio maps are quantitatively preserved in CS‐accelerated dissolved‐phase 129Xe imaging and to investigate the ...
Jemima H. Pilgrim‐Morris, Guilhem J. Collier, Ryan S. Munro, Graham Norquay, Neil J. Stewart, Jim M. Wild   +5 more
wiley   +2 more sources

Pore size estimation in axon‐mimicking microfibers with diffusion‐relaxation MRI [PDF]

Magnetic Resonance in Medicine, Volume 91, Issue 6, Page 2579-2596, June 2024.
Abstract Purpose This study aims to evaluate two distinct approaches for fiber radius estimation using diffusion‐relaxation MRI data acquired in biomimetic microfiber phantoms that mimic hollow axons. The methods considered are the spherical mean power‐law approach and a T2‐based pore size estimation technique.
Erick J. Canales‐Rodríguez, Marco Pizzolato, Feng‐Lei Zhou, Muhamed Barakovic, Jean‐Philippe Thiran, Derek K. Jones, Geoffrey J. M. Parker, Tim B. Dyrby   +7 more
wiley   +2 more sources

In Vivo Characterization of Magnetic Inclusions in the Subcortex From Nonexponential Transverse Relaxation Decay [PDF]

NMR in Biomedicine, Volume 38, Issue 6, June 2025.
Nonexponential transverse relaxation decay allows to characterize the spatial distribution of magnetic material within subcortical grey matter tissue. ABSTRACT According to theoretical studies, MRI signal decay due to transverse relaxation in brain tissue with magnetic inclusions (e.g., blood vessels and iron‐rich cells) is expected to follow a ...
Rita Oliveira, Quentin Raynaud, Ileana Jelescu, Valerij G. Kiselev, Evgeniya Kirilina, Antoine Lutti   +5 more
wiley   +2 more sources

Covariance Estimation for Wide Data

WIREs Computational Statistics, Volume 18, Issue 2, June 2026.
Covariance matrix estimation is fundamental to multivariate analysis, with applications spanning finance, genomics, climate science, and signal processing. This review synthesizes recent advances in high‐dimensional covariance estimation‐thresholding, linear and nonlinear shrinkage, graphical models, and random matrix theory‐under a unifying framework ...
Eran Raviv
wiley   +1 more source

V_a-Deformed Free Convolution

Mathematics
In this article, we study Va-transformation of a measure and of a convolution (denoted by a) defined for a∈R. We provide significant insights into the stability of the free Meixner family of probability measures under Va-transformation.
Fahad Alsharari, Raouf Fakhfakh
doaj   +1 more source

Free energy expansions of a conditional GinUE and large deviations of the smallest eigenvalue of the LUE

Communications on Pure and Applied Mathematics, Volume 78, Issue 12, Page 2247-2304, December 2025.
Abstract We consider a planar Coulomb gas ensemble of size N$N$ with the inverse temperature β=2$\beta =2$ and external potential Q(z)=|z|2−2clog|z−a|$Q(z)=|z|^2-2c \log |z-a|$, where c>0$c>0$ and a∈C$a \in \mathbb {C}$. Equivalently, this model can be realised as N$N$ eigenvalues of the complex Ginibre matrix of size (c+1)N×(c+1)N$(c+1) N \times (c+1)
Sung‐Soo Byun, Seong‐Mi Seo, Meng Yang   +2 more
wiley   +1 more source