Laura Astolas

Dr. Laura Astolas


Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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31 August 2010 in International Journal of Computer Vision
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LALaura Astolas
Laura Astolas
LFLuc Florack
Luc Florack

29 December 2010 in Conformal Geometry and Dynamics of the American Mathematical Society
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Journal Article
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LALaura Astolas
Laura Astolas
RKRiikka Kangaslampi
Riikka Kangaslampi
KPKirsi Peltonen
Kirsi Peltonen
A uniformly quasiregular mapping acting on a compact Riemannian manifold distorts the metric by a bounded amount, independently of the number of iterates. Such maps are rational with respect to some measurable conformal structure and there is a Fatou-Julia type theory associated with the dynamical system obtained by iterating these mappings. We study a rich subclass of uniformly quasiregular mappings that can be produced using an analogy of classical Lattès’ construction of chaotic rational functions acting on the extended planeC¯\bar {\mathbb {C}}. We show that there is a plenitude of compact manifolds that support these mappings. Moreover, we find that in some cases there are alternative ways to construct this type of mapping with different Julia sets.

13 August 2010 in Journal of Mathematical Imaging and Vision
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Journal Article
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LFLuc Florack
Luc Florack
EBEvgeniya Balmashnova
Evgeniya Balmashnova
LALaura Astolas
Laura Astolas
EBEllen Brunenberg
Ellen Brunenberg

21 September 2010 in Pattern Recognition
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Journal Article
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LALaura Astolas
Laura Astolas
AFAndrea Fuster
Andrea Fuster
LFLuc Florack
Luc Florack

1 July 2014 in BioTech
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LALaura Astolas
Laura Astolas
JMJaap Molenaar
Jaap Molenaar
Microarray data is often utilized in inferring regulatory networks. Quantile normalization (QN) is a popular method to reduce array-to-array variation. We show that in the context of time series measurements QN may not be the best choice for this task, especially not if the inference is based on continuous time ODE model. We propose an alternative normalization method that is better suited for network inference from time series data.

14 November 2014 in Axioms
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LALaura Astolas
Laura Astolas
NSNeda Sepasian
Neda Sepasian
THTom Dela Haije
Tom Dela Haije
AFAndrea Fuster
Andrea Fuster
LFLuc Florack
Luc Florack
In Riemannian geometry, a distance function is determined by an inner product on the tangent space. In Riemann–Finsler geometry, this distance function can be determined by a norm. This gives more freedom on the form of the so-called indicatrix or the set of unit vectors. This has some interesting applications, e.g., in medical image analysis, especially in diffusion weighted imaging (DWI). An important application of DWI is in the inference of the local architecture of the tissue, typically consisting of thin elongated structures, such as axons or muscle fibers, by measuring the constrained diffusion of water within the tissue. From high angular resolution diffusion imaging (HARDI) data, one can estimate the diffusion orientation distribution function (dODF), which indicates the relative diffusivity in all directions and can be represented by a spherical polynomial. We express this dODF as an equivalent spherical monomial (higher order tensor) to directly generalize the (second order) diffusion tensor approach. To enable efficient computation of Riemann–Finslerian quantities on diffusion weighted (DW)-images, such as the metric/norm tensor, we present a simple and efficient algorithm to invert even order spherical monomials, which extends the familiar inversion of diffusion tensors, i.e., symmetric matrices.