Publications associées à Multimodal microstructure imaging: joint T2-relaxometry and diffusometry to estimate myelin, intracellular, extracellular, and cerebrospinal fluid properties

Multiparametric Characterization and Spatial Distribution of Different MS Lesion Phenotypes

Tobias Kober, Tom Hilbert, Gian Franco Piredda

BACKGROUND AND PURPOSE: MS lesions exhibit varying degrees of axonal and myelin damage. A comprehensive description of lesion phenotypes could contribute to an improved radiologic evaluation of smoldering inflammation and remyelination processes. This stud ...

Amer Soc Neuroradiology2024

High brightness neutron source optimized for very high pulsed magnetic field experiments

Mina Akhyani

Conducting neutron scattering experiments in the presence of high pulsed magnetic fields, namely above 40 T, provides valuable information about the magnetic structures of materials. However, these experiments are challenging and time-consuming because the ...

EPFL2024

Fast, Broad-Band Magnetic Resonance Spectroscopy with Diamond Widefield Relaxometry

Hoda Shirzad, Mayeul Sylvain Chipaux

We present an alternative to conventional Electron the use of bulky magnets and magnetron equipment, we use the photoluminescence of an ensemble of Nitrogen-Vacancy centers at the surface of a diamond. Monitoring their relaxation time (or T1), we detected ...

AMER CHEMICAL SOC2023

Single Chip Dynamic Nuclear Polarization Microsystems

Nergiz Sahin Solmaz

Nuclear magnetic resonance (NMR) methods are powerful tools employed in many fields, including physics, chemistry, material science, biology, and medicine. The use of NMR methodologies in an even wider range of applications is often hindered by the relativ ...

EPFL2023

Diamond-Based Nanoscale Quantum Relaxometry for Sensing Free Radical Production in Cells

Hoda Shirzad, Mayeul Sylvain Chipaux

Diamond magnetometry makes use of fluorescent defects in diamonds to convert magnetic resonance signals into fluorescence. Because optical photons can be detected much more sensitively, this technique currently holds several sensitivity world records for r ...

WILEY-V C H VERLAG GMBH2022

Static and dynamic properties of non-collinear quantum antiferromagnets explored by neutron scattering

Luc Testa

This thesis is devoted to the investigation of static and dynamic properties of two different sets of quantum magnets with neutron scattering techniques and the help of linear spin wave theory. Both systems are copper-based with spin-1/2, which makes them ...

EPFL2021

Quantitative Microstructural Imaging for Clinical Use

Gian Franco Piredda

Today, Magnetic Resonance Imaging (MRI) is a well-established medical imaging modality thanks to its excellent soft tissue contrast. Conventional MR image contrasts can be weighted towards one or more physical properties that discriminate different tissues ...

EPFL2021

Mechanistic studies of DNP and applications of hyperpolarized probes to study renal physiology and metabolism

Alice Radaelli

Dissolution dynamic nuclear polarization (dDNP) is a powerful technique that enhances the magnetic resonance signal of nuclear spins by several orders of magnitude. DNP relies on the principle of cross-relaxation by electron spins driven out of equilibrium ...

EPFL2021

Scaling analyses for hyperpolarization transfer across a spin-diffusion barrier and into bulk solid media

Arthur César Pinon, David Lyndon Emsley, Bradley Floyd Chmelka

By analogy to heat and mass transfer film theory, a general approach is introduced for determining hyperpolarization transfer rates between dilute electron spins and a surrounding nuclear ensemble. These analyses provide new quantitative relationships for ...

2021

Endogenous O-17 Dynamic Nuclear Polarization of Gd-Doped CeO2 from 100 to 370 K

David Lyndon Emsley, Snaedis Björgvinsdóttir, Georges Guévork Jean-Jacques Menzildjian, Michael Allan Hope, Bowen Zhang, Moreno Lelli, Zhuoran Wang

O-17 NMR is an invaluable tool to study the structure and dynamics of oxide materials but remains challenging to apply in many systems. Even with isotopic enrichment, studies of samples with low masses and/or concentrations of the active species, such as t ...

2021

Spin-dependent charge transfer at chiral electrodes probed by magnetic resonance

Jean-Philippe Ansermet, Christophe Roussel, Felix Blumenschein, Mika Antero Tamski

Chirality-induced spin selectivity is evidenced by exciting the spin resonance of radicals in an electrochemical cell where the working electrode is covered with a chiral self-assembled monolayer. Because the electron transfer to and from the paramagnetic ...

ROYAL SOC CHEMISTRY2020

Comparison of 2D simultaneous multi-slice and 3D GRASE readout schemes for pseudo-continuous arterial spin labeling of cerebral perfusion at 3 T

Bénédicte Marie Maréchal, Tobias Kober, Tom Hilbert

Objective In this perfusion magnetic resonance imaging study, the performances of different pseudo-continuous arterial spin labeling (PCASL) sequences were compared: two-dimensional (2D) single-shot readout with simultaneous multislice (SMS), 2D single-sho ...

SPRINGER2021

Model-informed machine learning for multi-component T2 relaxometry

Jean-Philippe Thiran, Meritxell Bach Cuadra, Tobias Kober, Elda Fischi Gomez, Cristina Granziera, Tom Hilbert, Muhamed Barakovic, Gian Franco Piredda, Erick Jorge Canales Rodriguez, Marco Pizzolato, Thomas Yu

Recovering the distribution from multi-echo magnetic resonance (MR) signals is challenging but has high potential as it provides biomarkers characterizing the tissue micro-structure, such as the myelin water fraction (MWF). In this work, we propose to comb ...

2020

Nanodiamond Relaxometry-Based Detection of Free-Radical Species When Produced in Chemical Reactions in Biologically Relevant Conditions

Mayeul Sylvain Chipaux

Diamond magnetometry is a quantum sensing method involving detection of magnetic resonances with nanoscale resolution. For instance, T1 relaxation measurements, inspired by equivalent concepts in magnetic resonance imaging (MRI), provide a signal that is e ...

AMER CHEMICAL SOC2020

Origin and role of the cerebrospinal fluid bidirectional flow in the central canal

François Gallaire, Ludovic Pierre Gustave Keiser

Circulation of the cerebrospinal fluid (CSF) contributes to body axis formation and brain development. Here, we investigated the unexplained origins of the CSF flow bidirectionality in the central canal of the spinal cord of 30 hpf zebrafish embryos and it ...

2020

New Approaches to NMR Crystallography

Federico Maria Paruzzo

The first full protocol for nuclear magnetic resonance (NMR) crystallography (NMRX) using chemical shifts was developed a decade ago, and it combines experimental isotropic chemical shifts with crystal structure prediction (CSP) and with the calculation of ...

EPFL2019

Spin-Dependent Processes at Electrodes Detected by Simultaneously Performed EPR, Electrochemistry and EDMR

Felix Blumenschein

The electrically detected magnetic resonance (EDMR) results presented in this thesis demonstrate a spin dependence of the charge transfer between an electrode and an electrolyte. These results were found using simultaneous detection of continuous wave elec ...

EPFL2019

Longitudinal study of neonatal brain tissue volumes in preterm infants and their ability to predict neurodevelopmental outcome

Djalel Eddine Meskaldji, Laura Ioana Gui, Serafeim Loukas

Premature birth has been associated with poor neurodevelopmental outcomes. However, the relation between such outcomes and brain growth in the neonatal period has not yet been fully elucidated. This study investigates longitudinal brain development between ...

ACADEMIC PRESS INC ELSEVIER SCIENCE2019

Development and Optimization of Methods for Accelerated Magnetic Resonance Imaging

Tom Hilbert

Magnetic resonance imaging (MRI) has yielded great success as a medical imaging modality in the past decades, and its excellent soft tissue contrast is used in clinical routine to support diagnosis today. However, MRI is still facing challenges. For exampl ...

EPFL2018

Microwave Imaging of Brain Stroke : Contributions to Modeling and Inverse Problem Resolution

Mina Bjelogrlic

Brain stroke is an age-related illness which has become a major issue in our ageing societies. Early diagnosis and treatment are of high importance for the full recovery of the patient, as reminded in Anglo-Saxon countries by the abbreviation FAST (Face, A ...

EPFL2018