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 -
TY - JOUR
AB - Using inelastic cotunneling spectroscopy we observe a zero field splitting within the spin triplet manifold of Ge hut wire quantum dots. The states with spin ±1 in the confinement direction are energetically favored by up to 55 μeV compared to the spin 0 triplet state because of the strong spin–orbit coupling. The reported effect should be observable in a broad class of strongly confined hole quantum-dot systems and might need to be considered when operating hole spin qubits.
AU - Katsaros, Georgios
AU - Kukucka, Josip
AU - Vukušić, Lada
AU - Watzinger, Hannes
AU - Gao, Fei
AU - Wang, Ting
AU - Zhang, Jian-Jun
AU - Held, Karsten
ID - 8203
IS - 7
JF - Nano Letters
SN - 1530-6984
TI - Zero field splitting of heavy-hole states in quantum dots
VL - 20
ER -
TY - DATA
AB - These are the supplementary research data to the publication "Zero field splitting of heavy-hole states in quantum dots". All matrix files have the same format. Within each column the bias voltage is changed. Each column corresponds to either a different gate voltage or magnetic field. The voltage values are given in mV, the current values in pA. Find a specific description in the included Readme file.
AU - Katsaros, Georgios
ID - 7689
TI - Supplementary data for "Zero field splitting of heavy-hole states in quantum dots"
ER -
TY - JOUR
AB - Many-body localization provides a mechanism to avoid thermalization in isolated interacting quantum systems. The breakdown of thermalization may be complete, when all eigenstates in the many-body spectrum become localized, or partial, when the so-called many-body mobility edge separates localized and delocalized parts of the spectrum. Previously, De Roeck et al. [Phys. Rev. B 93, 014203 (2016)] suggested a possible instability of the many-body mobility edge in energy density. The local ergodic regions—so-called “bubbles”—resonantly spread throughout the system, leading to delocalization. In order to study such instability mechanism, in this work we design a model featuring many-body mobility edge in particle density: the states at small particle density are localized, while increasing the density of particles leads to delocalization. Using numerical simulations with matrix product states, we demonstrate the stability of many-body localization with respect to small bubbles in large dilute systems for experimentally relevant timescales. In addition, we demonstrate that processes where the bubble spreads are favored over processes that lead to resonant tunneling, suggesting a possible mechanism behind the observed stability of many-body mobility edge. We conclude by proposing experiments to probe particle density mobility edge in the Bose-Hubbard model.
AU - Brighi, Pietro
AU - Abanin, Dmitry A.
AU - Serbyn, Maksym
ID - 8308
IS - 6
JF - Physical Review B
SN - 2469-9950
TI - Stability of mobility edges in disordered interacting systems
VL - 102
ER -
TY - JOUR
AB - When can a polyomino piece of paper be folded into a unit cube? Prior work studied tree-like polyominoes, but polyominoes with holes remain an intriguing open problem. We present sufficient conditions for a polyomino with one or several holes to fold into a cube, and conditions under which cube folding is impossible. In particular, we show that all but five special “basic” holes guarantee foldability.
AU - Aichholzer, Oswin
AU - Akitaya, Hugo A.
AU - Cheung, Kenneth C.
AU - Demaine, Erik D.
AU - Demaine, Martin L.
AU - Fekete, Sándor P.
AU - Kleist, Linda
AU - Kostitsyna, Irina
AU - Löffler, Maarten
AU - Masárová, Zuzana
AU - Mundilova, Klara
AU - Schmidt, Christiane
ID - 8317
JF - Computational Geometry: Theory and Applications
SN - 09257721
TI - Folding polyominoes with holes into a cube
VL - 93
ER -
TY - JOUR
AB - Complex I is the first and the largest enzyme of respiratory chains in bacteria and mitochondria. The mechanism which couples spatially separated transfer of electrons to proton translocation in complex I is not known. Here we report five crystal structures of T. thermophilus enzyme in complex with NADH or quinone-like compounds. We also determined cryo-EM structures of major and minor native states of the complex, differing in the position of the peripheral arm. Crystal structures show that binding of quinone-like compounds (but not of NADH) leads to a related global conformational change, accompanied by local re-arrangements propagating from the quinone site to the nearest proton channel. Normal mode and molecular dynamics analyses indicate that these are likely to represent the first steps in the proton translocation mechanism. Our results suggest that quinone binding and chemistry play a key role in the coupling mechanism of complex I.
AU - Gutierrez-Fernandez, Javier
AU - Kaszuba, Karol
AU - Minhas, Gurdeep S.
AU - Baradaran, Rozbeh
AU - Tambalo, Margherita
AU - Gallagher, David T.
AU - Sazanov, Leonid A
ID - 8318
IS - 1
JF - Nature Communications
TI - Key role of quinone in the mechanism of respiratory complex I
VL - 11
ER -