A5042156891- CCD and CMOS Imaging Sensors
- Thin-Film Transistor Technologies
- Advanced Neuroimaging Techniques and Applications
- Advanced MRI Techniques and Applications
- Astronomical Observations and Instrumentation
- NMR spectroscopy and applications
- MRI in cancer diagnosis
- Infrared Target Detection Methodologies
- Silicon Nanostructures and Photoluminescence
- Transition Metal Oxide Nanomaterials
- Advanced Optical Sensing Technologies
- Advanced NMR Techniques and Applications
- Surface Roughness and Optical Measurements
- Silicon and Solar Cell Technologies
- Bone and Joint Diseases
- Electron and X-Ray Spectroscopy Techniques
- Tensor decomposition and applications
- Ion-surface interactions and analysis
- Analytical Chemistry and Sensors
Lund University
2016-2021
St Olav's University Hospital
2021
Random Walk Imaging
2019-2020
Instituto Politécnico de Lisboa
2004-2008
Instituto de Soldadura e Qualidade
2000-2001
Diffusion nuclear magnetic resonance (NMR) is a powerful technique for studying porous media, but yields ambiguous results when the sample comprises multiple regions with different pore sizes, shapes, and orientations. Inspired by solid-state NMR techniques correlating isotropic anisotropic chemical shifts, we propose diffusion method to resolve said ambiguity. Numerical data inversion relies on sparse representation of in basis radial axial diffusivities. Experiments are performed composite...
Abstract Despite their widespread use in non-invasive studies of porous materials, conventional MRI methods yield ambiguous results for microscopically heterogeneous materials such as brain tissue. While the forward link between microstructure and observables is well understood, inverse problem separating signal contributions from different microscopic pores notoriously difficult. Here, we introduce an experimental protocol where heterogeneity resolved by establishing 6D correlations...
Abstract Diffusion MRI techniques are used widely to study the characteristics of human brain connectome in vivo. However, resolve and characterise white matter (WM) fibres heterogeneous voxels remains a challenging problem typically approached with signal models that rely on prior information constraints. We have recently introduced 5D relaxation–diffusion correlation framework wherein multidimensional diffusion encoding strategies acquire data at multiple echo‐times increase amount encoded...
Specific features of white matter microstructure can be investigated by using biophysical models to interpret relaxation-diffusion MRI brain data. Although more intricate have the potential reveal details tissue, they also incur time-consuming parameter estimation that may converge inaccurate solutions due a prevalence local minima in degenerate fitting landscape. Machine-learning algorithms been proposed accelerate and increase robustness attained estimates. So far, learning-based...
In biological tissues, typical MRI voxels comprise multiple microscopic environments, the local organization of which can be captured by diffusion tensors. The measured signal can, therefore, written as multidimensional Laplace transform an intravoxel tensor distribution (DTD). Tensor‐valued encoding schemes have been designed to probe specific features DTD, and several algorithms introduced invert such data estimate statistical descriptors mean diffusivity, variance isotropic diffusivities,...
Abstract. Magnetic resonance imaging (MRI) is the primary method for noninvasive investigations of human brain in health, disease, and development but yields data that are difficult to interpret whenever millimeter-scale voxels contain multiple microscopic tissue environments with different chemical structural properties. We propose a novel MRI framework quantify heterogeneity living as spatially resolved five-dimensional relaxation–diffusion distributions by augmenting conventional...
Amorphous and microcrystalline glass/ZnO:Al/p(a-Si:H)/i(a-Si:H)/n(a-Si 1 - x C :H)/Al imagers with different n-layer resistivities were produced by plasma-enhanced chemical vapor deposition technique (PE-CVD). The transducer is a simple, large area p-i-n photodiode; an image projected onto the sensing element leads to spatially confined depletion regions that can be readout scanning photodiode low-power modulated laser beam. essence of scheme analog absence semiconductor arrays or electrode...
Diffusion tensor distribution (DTD) imaging builds on principles from diffusion, solid‐state and low‐field NMR spectroscopies, to quantify the contents of heterogeneous voxels as nonparametric distributions, with “size”, “shape” orientation having direct relations corresponding microstructural properties biological tissues. The approach requires acquisition multiple images a function magnitude, shape direction diffusion‐encoding gradients, leading long times unless fast image read‐out...
ABSTRACT Specific features of white-matter microstructure can be investigated by using biophysical models to interpret relaxation-diffusion MRI brain data. Although more intricate have the potential reveal details tissue, they also incur time-consuming parameter estimation that may con-verge inaccurate solutions due a prevalence local minima in degenerate fitting landscape. Machine-learning algorithms been proposed accelerate and increase robustness attained estimates. So far, learning-based...
ABSTRACT Diffusion MRI techniques are widely used to study in vivo changes the human brain connectome. However, resolve and characterise white matter fibres heterogeneous diffusion voxels remains a challenging problem typically approached with signal models that rely on prior information restrictive constraints. We have recently introduced 5D relaxation-diffusion correlation framework wherein multidimensional encoding strategies acquire data at multiple echo-times order increase amount of...
The present paper reports the optical properties of multilayer structures composed by p-i-n cells based on a-SiC:H or a-Si:H material. Different are studied in order to obtain image sensors that accomplish color filtering addition pattern recognition. A simple theoretical model is developed explain behavior and derive optical-readout experimental procedure. Electrical models for established simulation purposes compare photocurrent signals with data. numerical JV characteristic spectral...