TY - GEN
AB - A natural approach to generative modeling of videos is to represent them as a composition of moving objects. Recent works model a set of 2D sprites over a slowly-varying background, but without considering the underlying 3D scene that
gives rise to them. We instead propose to model a video as the view seen while moving through a scene with multiple 3D objects and a 3D background. Our model is trained from monocular videos without any supervision, yet learns to
generate coherent 3D scenes containing several moving objects. We conduct detailed experiments on two datasets, going beyond the visual complexity supported by state-of-the-art generative approaches. We evaluate our method on
depth-prediction and 3D object detection---tasks which cannot be addressed by those earlier works---and show it out-performs them even on 2D instance segmentation and tracking.
AU - Henderson, Paul M
AU - Lampert, Christoph
ID - 8188
T2 - arXiv
TI - Unsupervised object-centric video generation and decomposition in 3D
ER -
TY - COMP
AU - Hauschild, Robert
ID - 8181
TI - Amplified centrosomes in dendritic cells promote immune cell effector functions
ER -
TY - THES
AB - We present solutions to several problems originating from geometry and discrete mathematics: existence of equipartitions, maps without Tverberg multiple points, and inscribing quadrilaterals. Equivariant obstruction theory is the natural topological approach to these type of questions. However, for the specific problems we consider it had yielded only partial or no results. We get our results by complementing equivariant obstruction theory with other techniques from topology and geometry.
AU - Avvakumov, Sergey
ID - 8156
TI - Topological methods in geometry and discrete mathematics
ER -
TY - JOUR
AB - Understanding to what extent stem cell potential is a cell-intrinsic property or an emergent behavior coming from global tissue dynamics and geometry is a key outstanding question of systems and stem cell biology. Here, we propose a theory of stem cell dynamics as a stochastic competition for access to a spatially localized niche, giving rise to a stochastic conveyor-belt model. Cell divisions produce a steady cellular stream which advects cells away from the niche, while random rearrangements enable cells away from the niche to be favorably repositioned. Importantly, even when assuming that all cells in a tissue are molecularly equivalent, we predict a common (“universal”) functional dependence of the long-term clonal survival probability on distance from the niche, as well as the emergence of a well-defined number of functional stem cells, dependent only on the rate of random movements vs. mitosis-driven advection. We test the predictions of this theory on datasets of pubertal mammary gland tips and embryonic kidney tips, as well as homeostatic intestinal crypts. Importantly, we find good agreement for the predicted functional dependency of the competition as a function of position, and thus functional stem cell number in each organ. This argues for a key role of positional fluctuations in dictating stem cell number and dynamics, and we discuss the applicability of this theory to other settings.
AU - Corominas-Murtra, Bernat
AU - Scheele, Colinda L.G.J.
AU - Kishi, Kasumi
AU - Ellenbroek, Saskia I.J.
AU - Simons, Benjamin D.
AU - Van Rheenen, Jacco
AU - Hannezo, Edouard B
ID - 8220
IS - 29
JF - Proceedings of the National Academy of Sciences of the United States of America
TI - Stem cell lineage survival as a noisy competition for niche access
VL - 117
ER -
TY - JOUR
AB - We consider the following setting: suppose that we are given a manifold M in Rd with positive reach. Moreover assume that we have an embedded simplical complex A without boundary, whose vertex set lies on the manifold, is sufficiently dense and such that all simplices in A have sufficient quality. We prove that if, locally, interiors of the projection of the simplices onto the tangent space do not intersect, then A is a triangulation of the manifold, that is, they are homeomorphic.
AU - Boissonnat, Jean-Daniel
AU - Dyer, Ramsay
AU - Ghosh, Arijit
AU - Lieutier, Andre
AU - Wintraecken, Mathijs
ID - 8248
JF - Discrete and Computational Geometry
SN - 0179-5376
TI - Local conditions for triangulating submanifolds of Euclidean space
ER -