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Related papers: Optical Flow on Evolving Sphere-Like Surfaces

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In this paper, we develop a lattice Boltzmann scheme based on the Vielbein formalism for the study of fluid flows on spherical surfaces. The Vielbein vector field encodes all details related to the geometry of the underlying spherical…

We combine confocal imaging, microfluidics and image analysis to record 3D-images of cells in flow. This enables us to recover the full 3D representation of several hundred living cells per minute. Whereas 3D confocal imaging has thus far…

Fluid Dynamics · Physics 2017-09-19 S. Quint , A. F. Christ , A. Guckenberger , S. Himbert , L. Kaestner , S. Gekle , C. Wagner

An optical flow variational model is proposed for a sequence of images defined on a domain in $\mathbb{R}^2$. We introduce a regularization term given by the $L^1$ norm of a fractional differential operator. To solve the minimization…

Numerical Analysis · Mathematics 2015-12-07 Somayeh Gh. Bardeji , Isabel N. Figueiredo , Ercília Sousa

Normalizing flows have shown great promise for modelling flexible probability distributions in a computationally tractable way. However, whilst data is often naturally described on Riemannian manifolds such as spheres, torii, and hyperbolic…

Machine Learning · Statistics 2020-12-10 Emile Mathieu , Maximilian Nickel

We consider the evolution of an incompressible two-dimensional perfect fluid as the boundary of its domain is deformed in a prescribed fashion. The flow is taken to be initially steady, and the boundary deformation is assumed to be slow…

Analysis of PDEs · Mathematics 2007-05-23 J. Vanneste , D. Wirosoetisno

Below the scale of supergranules we find that cellular flows are present in the solar photosphere at two distinct size scales, approximately 2 Mm and 4 Mm, with distinct characteristic times. Simultaneously present in the flow is a…

Astrophysics · Physics 2015-06-24 J. K. Lawrence , A. C. Cadavid , A. Ruzmaikin

Zebrafish pretectal neurons exhibit specificities for large-field optic flow patterns associated with rotatory or translatory body motion. We investigate the hypothesis that these specificities reflect the input statistics of natural optic…

Neurons and Cognition · Quantitative Biology 2018-10-10 Gerrit A. Ecke , Fabian A. Mikulasch , Sebastian A. Bruijns , Thede Witschel , Aristides B. Arrenberg , Hanspeter A. Mallot

We describe the development of a tracking device, mounted on an epi-fluorescent inverted microscope, suited to obtain time resolved 3D Lagrangian tracks of fluorescent passive or active micro-objects in micro-fluidic devices. The system is…

Soft Condensed Matter · Physics 2017-06-07 T. Darnige , N. Figueroa-Morales , P. Bohec , A. Lindner , E. Clément

Experimental characterization of blood flow in living organisms is crucial for understanding the development and function of cardiovascular systems, but there have been no techniques reported for snapshot imaging of thick samples in large…

We study the deformation and motion of an erythrocyte in fluid flows via a lattice Boltzmann method. To this purpose, the bending rigidity and the elastic modulus of isotropic dilation are introduced and incorporated with the lattice…

Fluid Dynamics · Physics 2007-05-23 Huabing Li , Houhui Yi , Xiaowen Shan , Haiping Fang

An optical flow gradient algorithm was applied to spontaneously forming net- works of neurons and glia in culture imaged by fluorescence optical microscopy in order to map functional calcium signaling with single pixel resolution. Optical…

Computational Engineering, Finance, and Science · Computer Science 2010-01-22 Marius Buibas , Diana Yu , Krystal Nizar , Gabriel A. Silva

This paper deals with flow-induced shape transitions of elastic capsules. The state of the art concerning both theory and experiments is briefly reviewed starting with dynamically induced small deformation of initially spherical capsules…

Soft Condensed Matter · Physics 2011-04-25 Reimar Finken , Steffen Kessler , Udo Seifert

Widefield calcium imaging has recently emerged as a powerful experimental technique to record coordinated large-scale brain activity. These measurements present a unique opportunity to characterize spatiotemporal coherent structures that…

Neurons and Cognition · Quantitative Biology 2021-09-07 Nathaniel J Linden , Dennis R Tabuena , Nicholas A Steinmetz , William J Moody , Steven L Brunton , Bingni W Brunton

This paper considers membranes of globular structure in the framework of the cell model technique. Coupled micropolar and Brinkman-type equations are used to model the flow of micropolar fluid through a spherical cell, consisting of solid…

Fluid Dynamics · Physics 2020-05-05 D. Yu. Khanukaeva

Hydrodynamic instability of a gravity-driven flow down an inclined plane is investigated in the presence of a floating elastic plate which rests on the top surface of the flow. Linear instability of the system with respect to infinitesimal…

Fluid Dynamics · Physics 2020-03-17 Siluvai Antony Selvan , Sukhendu Ghosh , Harekrushna Behera , Michael H. Meylan

Cilia and flagella are actively bending slender organelles, performing functions such as motility, feeding and embryonic symmetry breaking. We review the mechanics of viscous-dominated microscale flow, including time-reversal symmetry, drag…

Quantitative Methods · Quantitative Biology 2013-09-06 Thomas D. Montenegro-Johnson , Andrew A. Smith , David J. Smith , Daniel Loghin , John R. Blake

The dynamics of thin liquid films flowing over a spinning disc is studied through a combination of experiments and direct numerical simulations. We consider a comprehensive range of interfacial flow regimes from waveless through to…

Fluid Dynamics · Physics 2024-12-18 Jason Stafford , Nwachukwu Uzo , Enrico Piccoli , Camille Petit , Omar K. Matar

There is increasing evidence that mammalian cells not only crawl on substrates but can also swim in fluids. To elucidate the mechanisms of the onset of motility of cells in suspension, a model which couples actin and myosin kinetics to…

Biological Physics · Physics 2019-09-18 Alexander Farutin , Jocelyn Etienne , Chaouqi Misbah , Pierre Recho

Vortex shedding by a swimming sphere in a viscous incompressible fluid is studied for surface modulation characterized by a superposition of dipolar and quadrupolar, as well as for quadrupolar and octupolar displacements, varying…

Fluid Dynamics · Physics 2019-06-26 B. U. Felderhof , R. B. Jones

The elastic flow, which is the $L^2$-gradient flow of the elastic energy, has several applications in geometry and elasticity theory. We present stable discretizations for the elastic flow in two-dimensional Riemannian manifolds that are…

Numerical Analysis · Mathematics 2019-11-01 John W. Barrett , Harald Garcke , Robert Nürnberg