Publications de Daniel Sage | EPFL Graph Search

Publications associées (72)

Pancreatic α- and β-Cellular Clocks Have Distinct Molecular Properties and Impact on Islet Hormone Secretion and Gene Expression

Michaël Unser, Daniel Sage, Frédéric Bruno Martin Gachon, Cédric Gobet

A critical role of circadian oscillators in orchestrating insulin secretion and islet gene transcription has been demonstrated recently. However, these studies focused on whole islets and did not explore the interplay between α-cell and β-cell clocks. We p ...

2017

Vision-based system for the control and measurement of wastewater flow rate in sewer systems

David Andrew Barry, Luca Rossi, Daniel Sage, Laurent Son Nguyen, Salim Kayal

Combined sewer overflows and stormwater discharges represent an important source of contamination to the environment. However, the harsh environment inside sewers and particular hydraulic conditions during rain events reduce the reliability of traditional ...

IWA Publishing2009

A Feasability Study of Color Flow Doppler Vectorization for Automated Blood Flow Monitoring

Daniel Sage, Anaïs Laure Marie-Thérèse Badoual

An ongoing issue in vascular medicine is the measure of the blood flow. Catheterization remains the gold standard measurement method, although non-invasive techniques are an area of intense research. We hereby present a computational method for real-time m ...

2016

A Snake-Based Approach to Accurate Determination of Both Contact Points and Contact Angles

Patrik Willi Hoffmann, Daniel Sage, Laura Barbieri, Gerit Kulik

We present a new method based on B-spline snakes (active contours) for measuring high-accuracy contact angles. In this approach, we avoid making physical assumptions by defining the contour of the drop as a versatile B-spline curve. When useful, we extend ...

Elsevier2006

Selective Visualization of Fluorescent Sterols in Caenorhabditis elegans by Bleach-Rate-Based Image Segmentation

Daniel Sage

The nematode Caenorhabditis elegans is a genetically tractable model organism to investigate sterol transport. In vivo imaging of the fluorescent sterol, dehydroergosterol (DHE), is challenged by C. elegans' high autofluorescence in the same spectral regio ...

Wiley InterScience2010

Predicting stem cell fate changes by differential cell cycle progression patterns

Marlen Knobloch, Matthias Lütolf, Daniel Sage, Daniel Andreas Schmitter, Yuya Okawa

Stem cell self-renewal, commitment and reprogramming rely on a poorly understood coordination of cell cycle progression and execution of cell fate choices. Using existing experimental paradigms, it has not been possible to probe this relationship systemati ...

Company of Biologists2012

Achieving high-resolution thermal imagery in low-contrast lake surface waters by aerial remote sensing and image registration

David Andrew Barry, Ulrich Lemmin, Daniel Sage, Abolfazl Irani Rahaghi

A two-platform measurement system for realizing airborne thermography of the Lake Surface Water Temperature (LSWT) with ~0.8 m pixel resolution (sub-pixel satellite scale) is presented. It consists of a tethered Balloon Launched Imaging and Monitoring Plat ...

2019

Multiresolution Monogenic Signal Analysis Using the Riesz-Laplace Wavelet Transform

Michaël Unser, Dimitri Nestor Alice Van De Ville, Daniel Sage

The monogenic signal is the natural 2-D counterpart of the 1-D analytic signal. We propose to transpose the concept to the wavelet domain by considering a complexified version of the Riesz transform which has the remarkable property of mapping a real-value ...

Institute of Electrical and Electronics Engineers2009

A 2D/3D image analysis system to track fluorescently labeled structures in rod-shaped cells: application to measure spindle pole asymmetry during mitosis

Michaël Unser, Daniel Sage, Viesturs Simanis, Daniel Andreas Schmitter

Background: The yeast Schizosaccharomyces pombe is frequently used as a model for studying the cell cycle. The cells are rod-shaped and divide by medial fission. The process of cell division, or cytokinesis, is controlled by a network of signaling proteins ...

Biomed Central Ltd2013

Flow measurements in sewer systems based on image analysis: automatic flow velocity algorithm

David Andrew Barry, Luca Rossi, Daniel Sage, Laurent Son Nguyen, Salim Kayal

Discharges of combined sewer overflows (CSOs) and stormwater are recognized as an important source of environmental contamination. However, the harsh sewer environment and particular hydraulic conditions during rain events reduce the reliability of traditi ...

IWA Publishing2011

Graphic: Graph-Based Hierarchical Clustering For Single-Molecule Localization Microscopy

Michaël Unser, Daniel Sage, Shayan Aziznejad

We propose a novel method for the clustering of point-cloud data that originate from single-molecule localization microscopy (SMLM). Our scheme has the ability to infer a hierarchical structure from the data. It takes a particular relevance when quantitati ...

IEEE2021

DeconvolutionLab2: An Open-Source Software for Deconvolution Microscopy

Michaël Unser, Daniel Sage, Cédric René Jean Vonesch, Ferréol Arnaud Marie Soulez, Laurène Donati

Images in fluorescence microscopy are inherently blurred due to the limit of diffraction of light. The purpose of deconvolution microscopy is to compensate numerically for this degradation. Deconvolution is widely used to restore fine details of 3D biologi ...

2017

Variational Phase Imaging Using the Transport-of-Intensity Equation

Michaël Unser, Daniel Sage, Emrah Bostan, Masih Nilchian, Emmanuel Augustin Julien Froustey

We introduce a variational phase retrieval algorithm for the imaging of transparent objects. Our formalism is based on the transport-of-intensity equation (TIE), which relates the phase of an optical field to the variation of its intensity along the direct ...

IEEE2016

A Psf-Based Approach To Biplane Calibration In 3D Super-Resolution Microscopy

Michaël Unser, Suliana Manley, Daniel Sage, Hagay Kirshner, Thomas Pengo

Super-resolution localization microscopy methods such as PALM and STORM have been shown to provide imaging with resolutions up to a few tens of nanometers while using relatively simple setups. Biplane PALM has extended the PALM technique to three-dimension ...

Ieee2012

Comparison of Deconvolution Software in 3D Microscopy: A User Point of View—Part 1

Alessandra Griffa, Daniel Sage

Deconvolution is an image restoration technique which improves image contrast, resolution and signal to noise ratio. In modern optical microscopy and biological research deconvolution is becoming a fundamental processing step which allows for better image ...

EMS2010

Coupled tomography and distinct-element-method approach to exploring the granular media microstructure in a jamming hourglass

Giorgio Margaritondo, Michaël Unser, Thomas Liebling, Daniel Sage, Lionel Pournin, Slobodan Mitrovic, Marco Ramaioli, Michel Tsukahara, Slobodan Mitrovic, Vincent Gajdosik

We describe an approach for exploring microscopic properties of granular media that couples x-ray microtomography and distinct-element-method (DEM) simulations through image analysis. We illustrate it via the study of the intriguing phenomenon of instant a ...

APS2008

Quantitative evaluation of software packages for single-molecule localization microscopy

Michaël Unser, Suliana Manley, Daniel Sage, Hagay Kirshner, Thomas Pengo

The quality of super-resolution images obtained by single-molecule localization microscopy (SMLM) depends largely on the software used to detect and accurately localize point sources. In this work, we focus on the computational aspects of super-resolution ...

Nature Publishing Group2015

Back to the future–20 years of progress and developments in photonic microscopy and biological imaging

Daniel Sage

In 2023, the ImaBio consortium (imabio-cnrs.fr), an interdisciplinary life microscopy research group at the Centre National de la Recherche Scientifique, celebrated its 20th anniversary. ImaBio contributes to the biological imaging community through organi ...

2024

Quantitative fluorescence loss in photobleaching for analysis of protein transport and aggregation

Daniel Sage

Background: Fluorescence loss in photobleaching (FLIP) is a widely used imaging technique, which provides information about protein dynamics in various cellular regions. In FLIP, a small cellular region is repeatedly illuminated by an intense laser pulse, ...

Biomed Central Ltd2012

Photobleaching Kinetics and Time-Integrated Emission of Fluorescent Probes in Cellular Membranes

Daniel Sage

Since the pioneering work of Hirschfeld, it is known that time-integrated emission (TiEm) of a fluorophore is independent of fluorescence quantum yield and illumination intensity. Practical implementation of this important result for determining exact prob ...

Mdpi Ag2014