13,412 research outputs found
Automatic Brain Tumor Segmentation using Cascaded Anisotropic Convolutional Neural Networks
A cascade of fully convolutional neural networks is proposed to segment
multi-modal Magnetic Resonance (MR) images with brain tumor into background and
three hierarchical regions: whole tumor, tumor core and enhancing tumor core.
The cascade is designed to decompose the multi-class segmentation problem into
a sequence of three binary segmentation problems according to the subregion
hierarchy. The whole tumor is segmented in the first step and the bounding box
of the result is used for the tumor core segmentation in the second step. The
enhancing tumor core is then segmented based on the bounding box of the tumor
core segmentation result. Our networks consist of multiple layers of
anisotropic and dilated convolution filters, and they are combined with
multi-view fusion to reduce false positives. Residual connections and
multi-scale predictions are employed in these networks to boost the
segmentation performance. Experiments with BraTS 2017 validation set show that
the proposed method achieved average Dice scores of 0.7859, 0.9050, 0.8378 for
enhancing tumor core, whole tumor and tumor core, respectively. The
corresponding values for BraTS 2017 testing set were 0.7831, 0.8739, and
0.7748, respectively.Comment: 12 pages, 5 figures. MICCAI Brats Challenge 201
K\"ahler-Ricci Flow on Projective Bundles over K\"ahler-Einstein Manifolds
We study the K\"ahler-Ricci flow on a class of projective bundles
over compact K\"ahler-Einstein
manifold . Assuming the initial K\"ahler metric admits a
U(1)-invariant momentum profile, we give a criterion, characterized by the
triple , under which the -fiber
collapses along the K\"ahler-Ricci flow and the projective bundle converges to
in Gromov-Hausdorff sense. Furthermore, the K\"ahler-Ricci flow must
have Type I singularity and is of (\C^n \times \mathbb{P}^1)-type. This
generalizes and extends part of Song-Weinkove's work \cite{SgWk09} on
Hirzebruch surfaces.Comment: revised version for publication, to appear in Trans. Amer. Math. So
A New Species of \u3ci\u3eHydrochara\u3c/i\u3e (Coleoptera: Hydrophilidae) from the Western Great Lakes Region
A new species Hydrochara simula (Coleoptera: Hydrophilidae) is described from Wis- consin and separated from other western Great Lakes species by a key. It is similar to H. obtusata (Say) and H. soror Smetana, but males can be easily recognized by a dorso-basal concavity of the aedeagus. Females can be distinguished from H. obtusata and H. soror by the more elongate penultimate segment of the maxillary palpus and other less consistent characters
Path isomorphisms between quiver Hecke and diagrammatic Bott-Samelson endomorphism algebras
We construct an explicit isomorphism between (truncations of) quiver Hecke
algebras and Elias-Williamson's diagrammatic endomorphism algebras of
Bott-Samelson bimodules. As a corollary, we deduce that the decomposition
numbers of these algebras (including as examples the symmetric groups and
generalised blob algebras) are tautologically equal to the associated
-Kazhdan-Lusztig polynomials, provided that the characteristic is greater
than the Coxeter number. We hence give an elementary and more explicit proof of
the main theorem of Riche-Williamson's recent monograph and extend their
categorical equivalence to cyclotomic Hecke algebras, thus solving
Libedinsky-Plaza's categorical blob conjecture
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