Publications associées à Oxymétrie colorimétrique

Assessing the effect of O2 dithering on CH4 oxidation on Pd/Al2O3

Under periodic lean/rich operation generated by repeated O2 pulses (O2-dithering), the abatement of CH4 and NO is enhanced compared to static operation. However, it is not well understood how the dithering parameters (pulse amplitude and frequency) affect ...

ELSEVIER SCIENCE SA2023

The influence of the gas on the dynamics of cavitation bubbles

Davide Bernardo Preso

Cavitation bubbles, extensively investigated in fluid mechanics, present enduring challenges in hydraulic machinery, while holding considerable potential for practical applications in biomedicine and sonochemistry. Despite more than a century of research, ...

EPFL2023

Performance of the new SmartCardia wireless, wearable oximeter: a comparison with arterial SaO2 in healthy volunteers

Francisco Javier Rincon Vallejos, Srinivasan Murali, Julien Pidoux

Background Our goal was to evaluate the performance of a new wearable arm located pulse oximeter. Methods Twelve volunteers were monitored with three pulse oximeters and underwent desaturation to 70% SaO(2). We compared the accuracy of SpO(2) reading from ...

BMC2022

2.5 Hz sample rate time-domain near-infrared optical tomography based on SPAD-camera image tissue hemodynamics

Edoardo Charbon, Scott Anthony Lindner, Martin Wolf, Jingjing Jiang

Tim-domain near-infrared optical tomography (TD NIROT) techniques based on diffuse light were gaining performance over the last years. They are capable of imaging tissue at several centimeters depth and reveal clinically relevant information, such as tissu ...

OPTICAL SOC AMER2022

A Delta Sigma-Modulated Sample and Average Common-Mode Feedback Technique for Capacitively Coupled Amplifiers in a 192-nW Acoustic Analog Front-End

Kyojin Choo

This work presents an acoustic analog front-end based on a delta sigma-modulated sample and average common-mode feedback technique. The proposed feedback offers a process and temperature stable high pass (HP) frequency corner, unity dc feedback gain, and a ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Influence of Oxidative Stress on Time-Resolved Oxygen Detection by [Ru(Phen)3]2+ In Vivo and In Vitro

Georges Wagnières, Veronika Huntosova

Detection of tissue and cell oxygenation is of high importance in fundamental biological and in many medical applications, particularly for monitoring dysfunction in the early stages of cancer. Measurements of the luminescence lifetimes of molecular probes ...

2021

Acute and Long-Term Effects of Aortic Compliance Decrease on Central Hemodynamics: A Modeling Analysis

Nikolaos Stergiopoulos, Georgios Rovas, Vasiliki Bikia, Stamatia Zoi Pagoulatou

Aortic compliance is an important determinant of cardiac afterload and a contributor to cardiovascular morbidity. In the present study, we sought to provide in silico insights into the acute as well as long-term effects of aortic compliance decrease on cen ...

FRONTIERS MEDIA SA2021

Spatial evaluation of potential saturation and contrast effects of discomfort glare in an open-plan office

Marilyne Andersen, Jan Wienold, Geraldine Cai Ting Quek, Stephen William Wasilewski

This paper analyzes the relative distribution of annual saturation and contrast effects of discomfort glare in a deep open-plan office. A previous comparative study has shown that while hybrid glare metrics were found to predict glare well in most scenario ...

2021

Non-invasive pulmonary artery pressure estimation by electrical impedance tomography in a controlled hypoxemia study in healthy subjects

Jean-Philippe Thiran, Mathieu Lemay, Fabian Braun, Martin Proença

Pulmonary hypertension is a hemodynamic disorder defined by an abnormal elevation of pulmonary artery pressure (PAP). Current options for measuring PAP are limited in clinical practice. The aim of this study was to evaluate if electrical impedance tomograp ...

NATURE RESEARCH2020

Integrating regional perfusion CT information to improve prediction of infarction after stroke

Dimitri Nestor Alice Van De Ville, Maria Giulia Preti, Elisabeth Anne Dirren

Physiological evidence suggests that neighboring brain regions have similar perfusion characteristics (vascular supply, collateral blood flow). It is largely unknown whether integrating perfusion CT (pCT) information from the area surrounding a given voxel ...

SAGE PUBLICATIONS INC2020

Oxygen availability in a HAPE-positive and a HAPE-negative woman before and during a visit to 3480 meters

Johannes Burtscher

Background: Testing the hypoxic ventilatory response (HVR) at low-altitude helps to detect those who do not hyperventilate appropriately in hypoxia but might not necessarily predict the HVR and the risk to develop acute mountain sickness (AMS) at high alti ...

ELSEVIER2020

Physiological Responses in Humans Acutely Exposed to High Altitude (3480 m): Minute Ventilation and Oxygenation Are Predictive for the Development of Acute Mountain Sickness

Johannes Burtscher

Burtscher, Martin, Michael Philadelphy, Hannes Gatterer, Johannes Burtscher, Martin Faulhaber, Werner Nachbauer, and Rudolf Likar. Physiological responses in humans acutely exposed to high altitude (3480 m): Minute ventilation and oxygenation are predictiv ...

MARY ANN LIEBERT, INC2019

Ultrafast nuclear dynamics of the acetylene cation C2H2+ and its impact on the infrared probe pulse induced C-H bond breaking efficiency

Ursula Röthlisberger, Swarnendu Bhattacharyya

The ultrafast nuclear dynamics of the acetylene cation C2H2+ following photoionization of the neutral molecule is investigated using an extreme-ultraviolet pump/infrared probe setup. The observed modulation of the C2H+ fragment ion yield with pump-probe de ...

2019

Noninvasive measurement of stroke volume changes in critically ill patients by means of electrical impedance tomography

Jean-Philippe Thiran, Fabian Braun, Mathieu Lemay, Martin Proença

Previous animal experiments have suggested that electrical impedance tomography (EIT) has the ability to noninvasively track changes in cardiac stroke volume (SV). The present study intended to reproduce these findings in patients during a fluid challenge. ...

SPRINGER HEIDELBERG2020

Investigating the variability of cardiac pulse artifacts across heartbeats in simultaneous EEG-fMRI recordings: A 7T study

Rolf Gruetter, João Pedro Forjaco Jorge, Lucie Bréchet

Electroencephalography (EEG) recordings performed in magnetic resonance imaging (MRI) scanners are affected by complex artifacts caused by heart function, often termed pulse artifacts (PAs). PAs can strongly compromise EEG data quality, and remain an open ...

2019

Signal processing techniques for cardiovascular monitoring applications using conventional and video-based photoplethysmography

Sibylle Fallet

Photoplethysmography (PPG)-based monitoring devices will probably play a decisive role in healthcare environment of the future, which will be preventive, predictive, personalized and participatory. Indeed, this optical technology presents several practical ...

EPFL2018

Multispectral Near-Infrared Optical Tomography for Cancer Hypoxia Study in Mice

Scott Anthony Lindner, Matthias Wolf, Jingjing Jiang, Markus Rudin

Oxygenation of a tumor is one of the most important predictive factors: hypoxia is associated with aggressive tumors and substantially lower survival rate. Despite this high relevance of tumor oxygenation, there is currently no bedside technique available ...

SPRINGER INTERNATIONAL PUBLISHING AG2018

An inverse problem for a semilinear parabolic equation arising from cardiac electrophysiology

Andrea Manzoni

In this paper we develop theoretical analysis and numerical reconstruction techniques for the solution of an inverse boundary value problem dealing with the nonlinear, time-dependent monodomain equation, which models the evolution of the electric potential ...

Iop Publishing Ltd2017

Negligible interaction of [Ru(Phen) 3 ] 2+ with human serum albumin makes it promising for a reliable in vivo assessment of the tissue oxygenation

Georges Wagnières, Veronika Huntosova

The interaction between a ruthenium - based water soluble oxygen probe ([Ru(Phen)3]2+, phen - phenanthroline) and human serum albumin (HSA) was investigated with the aim of describing the influence of HSA on the [Ru(Phen)3]2+ luminescence properties. Nowad ...

Elsevier2017

Statistical parametric mapping of stimuli evoked changes in total blood flow velocity in the mouse cortex obtained with extended-focus optical coherence microscopy

Theo Lasser, Paul James Marchand, Vincent Khashayar Shamaei, Arno Pino Bouwens, Tristan Bolmont, Daniel Pawel Szlag, Jérôme Extermann, David Nguyen

Functional magnetic resonance (fMRI) imaging is the current gold-standard in neuroimaging. fMRI exploits local changes in blood oxygenation to map neuronal activity over the entire brain. However, its spatial resolution is currently limited to a few hundre ...

Optical Soc Amer2017