0000000000399633

AUTHOR

A. Oliver

Graph Cut Energy Minimization in a Probabilistic Learning Framework for 3D Prostate Segmentation in MRI

International audience; Variations in inter-patient prostate shape, and size and imaging artifacts in magnetic resonance images (MRI) hinders automatic accurate prostate segmentation. In this paper we propose a graph cut based energy minimization of the posterior probabilities obtained in a supervised learning schema for automatic 3D segmentation of the prostate in MRI. A probabilistic classification of the prostate voxels is achieved with a probabilistic atlas and a random forest based learning framework. The posterior probabilities are combined to obtain the likelihood of a voxel being prostate. Finally, 3D graph cut based energy minimization in the stochastic space provides segmentation …

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A Mumford-Shah functional based variational model with contour, shape, and probability prior information for prostate segmentation

Abstract: Inter patient shape, size and intensity variations of the prostate in transrectal ultrasound (TRUS) images challenge automatic segmentation of the prostate. In this paper we propose a variational model driven by Mumford-Shah (MS) functional for segmenting the prostate. Parametric representation of the implicit curve is derived from principal component analysis (PCA) of the signed distance representation of the labeled training data to impose shape prior. Posterior probability of the prostate region determined from random forest classification facilitates initialization and propagation of our model in a MS energy minimization framework. The proposed method achieves mean Dice simila…

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Spectral clustering to model deformations for fast multimodal prostate registration

International audience; This paper proposes a method to learn deformation parameters off-line for fast multimodal registration of ultrasound and magnetic resonance prostate images during ultrasound guided needle biopsy. The method is based on a learning phase where deformation models are built from the deformation parameters of a splinebased non-linear diffeomorphism between training ultrasound and magnetic resonance prostate images using spectral clustering. Deformation models comprising of the eigen-modes of each cluster in a Gaussian space are applied on a test magnetic resonance image to register with the test ultrasound prostate image. The deformation model with the least registration …

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Effect of entrepreneurship education on entrepreneurship intention and related outcomes in educational contexts: a meta-analysis

Abstract Although some meta-analyses have investigated the effect of Entrepreneurship Education (EE), they mixed studies with high and low methodological quality. Thus, their results might overestimate the impact. This paper aims to examine the efficacy of the EE in student samples, attending to studies with a pre-posttest design and a control group. The results showed small effect sizes for EE in increasing Entrepreneurship Intention (EI) and Self-efficacy. Moreover, meta-regression confirmed that the duration of intervention programs predicted larger effect sizes for the EI. Finally, the practical implications of other potential moderator variables are discussed.

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