111 research outputs found
OctNetFusion: Learning Depth Fusion from Data
In this paper, we present a learning based approach to depth fusion, i.e.,
dense 3D reconstruction from multiple depth images. The most common approach to
depth fusion is based on averaging truncated signed distance functions, which
was originally proposed by Curless and Levoy in 1996. While this method is
simple and provides great results, it is not able to reconstruct (partially)
occluded surfaces and requires a large number frames to filter out sensor noise
and outliers. Motivated by the availability of large 3D model repositories and
recent advances in deep learning, we present a novel 3D CNN architecture that
learns to predict an implicit surface representation from the input depth maps.
Our learning based method significantly outperforms the traditional volumetric
fusion approach in terms of noise reduction and outlier suppression. By
learning the structure of real world 3D objects and scenes, our approach is
further able to reconstruct occluded regions and to fill in gaps in the
reconstruction. We demonstrate that our learning based approach outperforms
both vanilla TSDF fusion as well as TV-L1 fusion on the task of volumetric
fusion. Further, we demonstrate state-of-the-art 3D shape completion results.Comment: 3DV 2017, https://github.com/griegler/octnetfusio
A comprehensive evaluation of the activity and selectivity profile of ligands for RGD-binding integrins
Integrins, a diverse class of heterodimeric cell surface receptors, are key regulators of cell structure and behaviour, affecting cell morphology, proliferation, survival and differentiation. Consequently, mutations in specific integrins, or their deregulated expression, are associated with a variety of diseases. In the last decades, many integrin-specific ligands have been developed and used for modulation of integrin function in medical as well as biophysical studies. The IC50-values reported for these ligands strongly vary and are measured using different cell-based and cell-free systems. A systematic comparison of these values is of high importance for selecting the optimal ligands for given applications. In this study, we evaluate a wide range of ligands for their binding affinity towards the RGD-binding integrins avß3, avß5, avß6, avß8, a5ß1, aIIbß3, using homogenous ELISA-like solid phase binding assay.Postprint (published version
Chemical order transitions within extended interfacial segregation zones in NbMoTaW
Interfacial segregation and chemical short-range ordering influence the
behavior of grain boundaries in complex concentrated alloys. In this study, we
use atomistic modeling of a NbMoTaW refractory complex concentrated alloy to
provide insight into the interplay between these two phenomena. Hybrid Monte
Carlo and molecular dynamics simulations are performed on columnar grain models
to identify equilibrium grain boundary structures. Our results reveal extended
near-boundary segregation zones that are much larger than traditional
segregation regions, which also exhibit chemical patterning that bridges the
interfacial and grain interior regions. Furthermore, structural transitions
pertaining to an A2-to-B2 transformation are observed within these extended
segregation zones. Both grain size and temperature are found to significantly
alter the widths of these regions. Analysis of chemical short-range order
indicates that not all pairwise elemental interactions are affected by the
presence of a grain boundary equally, as only a subset of elemental clustering
types are more likely to reside near certain boundaries. The results emphasize
the increased chemical complexity that is associated with near-boundary
segregation zones and demonstrate the unique nature of interfacial segregation
in complex concentrated alloys
Recommended from our members
Reduced Intestinal Tumorigenesis in APCmin Mice Lacking Melanin-Concentrating Hormone
Background: Melanin-concentrating hormone (MCH) is an evolutionary conserved hypothalamic neuropeptide that in mammals primarily regulates appetite and energy balance. We have recently identified a novel role for MCH in intestinal inflammation by demonstrating attenuated experimental colitis in MCH deficient mice or wild type mice treated with an anti-MCH antibody. Therefore, targeting MCH has been proposed for the treatment of inflammatory bowel disease. Given the link between chronic intestinal inflammation and colorectal cancer, in the present study we sought to investigate whether blocking MCH might have effects on intestinal tumorigenesis that are independent of inflammation. Methodology Tumor development was evaluated in MCH-deficient mice crossed to the APCmin mice which develop spontaneously intestinal adenomas. A different cohort of MCH−/− and MCH+/+ mice in the APCmin background was treated with dextran sodium sulphate (DSS) to induce inflammation-dependent colorectal tumors. In Caco2 human colorectal adenocarcinoma cells, the role of MCH on cell survival, proliferation and apoptosis was investigated. Results: APCmin mice lacking MCH developed fewer, smaller and less dysplastic tumors in the intestine and colon which at the molecular level are characterized by attenuated activation of the wnt/beta-catenin signaling pathway and increased apoptotic indices. Form a mechanistic point of view, MCH increased the survival of colonic adenocarcinoma Caco2 cells via inhibiting apoptosis, consistent with the mouse studies. Conclusion: In addition to modulating inflammation, MCH was found to promote intestinal tumorigenesis at least in part by inhibiting epithelial cell apoptosis. Thereby, blocking MCH as a therapeutic approach is expected to decrease the risk for colorectal cancer
From the Dyson-Schwinger to the Transport Equation in the Background Field Gauge of QCD
The non-equilibrium quantum field dynamics is usually described in the
closed-time-path formalism. The initial state correlations are introduced into
the generating functional by non-local source terms. We propose a functional
approach to the Dyson-Schwinger equation, which treats the non-local and local
source terms in the same way. In this approach, the generating functional is
formulated for the connected Green functions and one-particle-irreducible
vertices. The great advantages of our approach over the widely used
two-particle-irreducible method are that it is much simpler and that it is easy
to implement the procedure in a computer program to automatically generate the
Feynman diagrams for a given process. The method is then applied to a pure
gluon plasma to derive the gauge-covariant transport equation from the
Dyson-Schwinger equation in the background covariant gauge. We discuss the
structure of the kinetic equation and show its relationship with the classical
one. We derive the gauge-covariant collision part and present an approximation
in the vicinity of equilibrium. The role of the non-local source kernel in the
non-equilibrium system is discussed in the context of a free scalar field.Comment: Revtex 4, 37 pages, 6 figures, with section VI rewritten and some
errors corrected, final version to be published by Nucl. Phys.
Recommended from our members
The normalisation of Food Aid: What happened to feeding people well?
In the UK, food poverty has increased in the last 15 years and the food aid supply chain that has emerged to tackle it is now roughly 10 years old. In this time, we have seen the food aid supply chain grow at a rate that has astounded many. Recently that growth has been aided by a grant of £20m from a large supermarket chain. It appears institutionalisation is just around the corner, if not already here. It also appears that there is far greater emphasis on dealing with the symptoms as opposed to solving the root causes of the problem. As an opinion piece, this paper reflects on some of the prevalent issues, and suggests some ways forward
Recommended from our members
Large-scale mapping of mutations affecting zebrafish development
BACKGROUND: Large-scale mutagenesis screens in the zebrafish employing the mutagen ENU have isolated several hundred mutant loci that represent putative developmental control genes. In order to realize the potential of such screens, systematic genetic mapping of the mutations is necessary. Here we report on a large-scale effort to map the mutations generated in mutagenesis screening at the Max Planck Institute for Developmental Biology by genome scanning with microsatellite markers. RESULTS: We have selected a set of microsatellite markers and developed methods and scoring criteria suitable for efficient, high-throughput genome scanning. We have used these methods to successfully obtain a rough map position for 319 mutant loci from the Tübingen I mutagenesis screen and subsequent screening of the mutant collection. For 277 of these the corresponding gene is not yet identified. Mapping was successful for 80 % of the tested loci. By comparing 21 mutation and gene positions of cloned mutations we have validated the correctness of our linkage group assignments and estimated the standard error of our map positions to be approximately 6 cM. CONCLUSION: By obtaining rough map positions for over 300 zebrafish loci with developmental phenotypes, we have generated a dataset that will be useful not only for cloning of the affected genes, but also to suggest allelism of mutations with similar phenotypes that will be identified in future screens. Furthermore this work validates the usefulness of our methodology for rapid, systematic and inexpensive microsatellite mapping of zebrafish mutations
- …