Publications de Kai Hassler | EPFL Graph Search

Sparsity-Driven Reconstruction for FDOT With Anatomical Priors

Michaël Unser, Jean-Charles Baritaux, Kai Hassler, Sebanti Sanyal, Martina Bucher

In this paper we propose a method based on (2, 1)-mixed-norm penalization for incorporating a structural prior in FDOT image reconstruction. The effect of (2, 1)-mixed-norm penalization is twofold: first, a sparsifying effect which isolates few anatomical ...

Institute of Electrical and Electronics Engineers2011

An Efficient Numerical Method for General

Michaël Unser, Jean-Charles Baritaux, Kai Hassler

Reconstruction algorithms for fluorescence tomography have to address two crucial issues : 1) the ill-posedness of the reconstruction problem, 2) the large scale of numerical problems arising from imaging of 3-D samples. Our contribution is the design and ...

Institute of Electrical and Electronics Engineers2010

Dynamic disorder in horseradish peroxidase observed with total internal reflection fluorescence correlation spectroscopy

Theo Lasser, Kai Hassler

This paper discusses the application of objective-type total internal reflection fluorescence correlation spectroscopy (TIR-FCS) to the study of the kinetics of immobilized horseradish peroxidase on a single molecule level. Objective-type TIR-FCS combines ...

2007

Single molecule detection and fluorescence correlation spectroscopy on surfaces

Kai Hassler

In this thesis a new approach for single molecule detection and analysis is explored. This approach is based on the combination of two well established methods, fluorescence correlation spectroscopy (FCS) and total internal reflection fluorescence microsco ...

EPFL2006

Time-resolved Hadamard fluorescence imaging

Theo Lasser, Kai Hassler

We present a new concept for fluorescence lifetime imaging (FLIM) based on time-resolved Hadamard imaging (HI). HI allows image acquisition by use of one single-point detector without requiring a moving scanning stage. Moreover, it reduces the influence of ...

2005

Total internal reflection fluorescence correlation spectroscopy (TIR-FCS) with low background and high count-rate per molecule

Theo Lasser, Marcel Leutenegger, Kai Hassler, Ramachandra Rao

We designed a fluorescence correlation spectroscopy (FCS) system for measurements on surfaces. The system consists of an objective-type total internal reflection fluorescence (TIRF) microscopy setup, adapted to measure FCS. Here, the fluorescence exciting ...

2005

Speckle statistics in optical coherence tomography

Theo Lasser, Boris Clément Karamata, Kai Hassler, Markus Laubscher

The two previously reported calculations of the amplitude distribution of speckles in optical coherence tomography, each based on a different mathematical formulation, yield different results. We show that a modification of an initial assumption in one of ...

2005

High count rates with total internal reflection fluorescence correlation spectroscopy

Theo Lasser, Kai Hassler

We achieved photon count rates per molecule as high as with commonly used confocal fluorescence correlation spectroscopy instruments using a new total internal reflection fluorescence correlation spectroscopy system based on an epi-illumination configurati ...

2005