Publications related to Gas exchange

In vivo application and validation of a novel noninvasive method to estimate the end-systolic elastance

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

Accurate assessment of the left ventricular (LV) systolic function is indispensable in the clinic. However, estimation of a precise index of cardiac contractility, i.e., the end-systolic elastance (E-es), is invasive and cannot be established as clinical r ...

2021

Plant wax and carbon isotope response to heat and drought in the conifer Juniperus monosperma

Charlotte Grossiord

Plant waxes, including n-alkanes, are commonly used for a wide range of paleo-applications. Several common traits of n-alkanes that are used as paleo-proxies include chain length distribution and average chain length (ACL), as well as plant wax carbon and ...

2021

Estimation of Left Ventricular End-Systolic Elastance From Brachial Pressure Waveform via Deep Learning

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

Determination of left ventricular (LV) end-systolic elastance (E- es ) is of utmost importance for assessing the cardiac systolic function and hemodynamical state in humans. Yet, the clinical use of E- es is not established due to the invasive nature and h ...

FRONTIERS MEDIA SA2021

The response of stomatal conductance to seasonal drought in tropical forests

Charlotte Grossiord, Jin Wu

Stomata regulate CO2 uptake for photosynthesis and water loss through transpiration. The approaches used to represent stomatal conductance (g s) in models vary. In particular, current understanding of drivers of the variation in a key parameter in those mo ...

2020

The impact of heart rate on pulse wave velocity: an in-silico evaluation

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

Background: Clinical and experimental evidence regarding the influence of heart rate (HR) on arterial stiffness and its surrogate marker carotid-to-femoral pulse wave velocity (cf-PWV) is conflicting. We aimed to evaluate the effect of HR on cf-PWV measure ...

LIPPINCOTT WILLIAMS & WILKINS2020

Acute effects of transcatheter aortic valve replacement on the ventricular-aortic interaction

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

Transcatheter aortic valve replacement (TAVR) is increasingly used to treat severe aortic stenosis (AS) patients. However, little is known regarding the direct effect of TAVR on the ventricular-aortic interaction. In the present study, we aimed to investig ...

AMER PHYSIOLOGICAL SOC2020

Interplay of hyporheic exchange and fine particle deposition in a riverbed

David Andrew Barry, Pei Zhang

Hyporheic flow transports fine particles into the riverbed, which can lead to clogging of the bed and in turn affect hyporheic flow and exchange processes. Field measurements and numerical simulations show the formation of a low-permeability layer (LPL) ne ...

2019

Spatiotemporal Drivers of CO2 Dynamics and Evasion Fluxes from Mountain Streams

Asa Lovisa Viktoria Horgby

Inland waters are key components of the global carbon cycle, emitting a substantial amount of carbon dioxide (CO2) to the atmosphere. Climate change and global warming affect mountain catchments significantly, leading to glacier retreat and changing precip ...

EPFL2019

Effective segmentation of fresh post-mortem murine lung parenchyma in phase contrast X-ray tomographic microscopy images

Goran Lovric, Marco Stampanoni

The acinus represents the functional unit of the mammalian lung. It is defined as the small tree of gas-exchanging airways, which is fed by the most distal purely conducting airway. Different hypotheses exist on how the fine structure of the acinus changes ...

Iop Publishing Ltd2017

Tomographic in vivo microscopy for the study of lung physiology at the alveolar level

Goran Lovric, Marco Stampanoni

Lungs represent the essential part of the mammalian respiratory system, which is reflected in the fact that lung failure still is one of the leading causes of morbidity and mortality worldwide. Establishing the connection between macroscopic observations o ...

Nature Research2017

Automated computer-assisted quantitative analysis of intact murine lungs at the alveolar scale

Goran Lovric, Marco Stampanoni

Using state-of-the-art X-ray tomographic microscopy we can image lung tissue in three dimensions in intact animals down to a micrometer precision. The structural complexity and hierarchical branching scheme of the lung at this level of details, however, re ...

Public Library of Science2017

Water exchange studies of lanthanide complexes and aqua ions

Shima Karimi

Complexes of lanthanide (III) ions have been used in structural studies of biomolecules and as contrast agents (CA). Clinically approved CAs have only one water molecule in their first coordination sphere. Structure and water exchange rate of these complex ...

EPFL2016

Water Exchange on [Ln(DO3A)(H2O)2] and [Ln(DTTA–Me)(H2O)2]− Studied by Variable Temperature, Pressure, and Magnetic Field NMR

Lothar Helm, Shima Karimi

Water exchange kinetics of [Ln(L)(H2O)2]x complexes (Ln = Pr, Nd, Dy, Tm, and Yb; L = DO3A and DTTA–Me) were studied by 17O NMR spectroscopy as a function of temperature, pressure, and frequency and by 1H nuclear magnetic relaxation dispersion. Water excha ...

American Chemical Society2016

Quantum Chemical Study of the Water Exchange Mechanism of the Americyl(VI) Aqua Ion

François Rotzinger, Alberto Fabrizio

The water exchange reaction of the americyl(VI) aqua ion was investigated with quantum chemical methods, density functional theory (DFT), and wave function theory (WFT). Associative and dissociative substitution mechanisms were studied, whereby DFT produce ...

American Chemical Society2016

Complexation of [Gd(DTTA–Me)(H2O)2]− by Fluoride and Its Consequences to Water Exchange

Lothar Helm, Loïck Moriggi, Shima Karimi, Gail Ruth Hunter

The displacement of water molecule(s) from the inner coordination sphere of [Gd(DTTA–Me)(H2O)2]− (DTTA = ethylenetriamine-N,N,N″,N″-tetraacetate) by fluoride has been studied by multinuclear NMR relaxation (1H, 17O, 19F) and DFT calculations. Fluoride anio ...

American Chemical Society2016

Gas Sampling Using Convection and Humidity Stabilization to Improve Point Gas Sensor Responses

Emily Ann Hammes

Many diseases including sick building syndrome, respiratory problems and cancers can be caused by exposure to high concentrations of toxins commonly used in modern building materials, paints, glues and furniture. To minimize exposure to these toxins, it is ...

EPFL2016

PEGylated DOTA-AHA-Based Gd-III Chelates: A Relaxometric Study

Lothar Helm, Shima Karimi

Three PEGylated derivatives of 6-amino-2-[4,7,10-tris(carboxymethyl)-1,4,7,10-tetrazacyclododec-1-yl]hexanoic acid (DOTA-AHA) with different molecular weights were prepared and characterized. Their Gd-III chelates were studied in aqueous solution through v ...

Wiley-Blackwell2015

Investigation of the water exchange mechanism of the Plutonyl(VI) and Uranyl(VI) ions with quantum chemical methods

François Rotzinger, Antonio Prlj

The water exchange reactions of PuO2(OH2)(5) and UO2(OH2)(5) were investigated with density functional theory (DFT) and wave function theory (WFT). Geometries and vibrational frequencies were calculated with DFT and CPCM hydration. The electron ...

Taylor & Francis2015

Homogenization of a multiscale viscoelastic model with nonlocal damping, application to the human lungs

Paul Isaac Denis Louis Marie Cazeaux

We are interested in the mathematical modeling of the deformation of the human lung tissue, called the lung parenchyma, during the respiration process. The parenchyma is a foam-like elastic material containing millions of air-filled alveoli connected by a ...

World Scientific Publ Co Pte Ltd2015

Gd(DOTAlaP): Exploring the Boundaries of Fast Water Exchange in Gadolinium-Based Magnetic Resonance Imaging Contrast Agents

Lothar Helm, Shima Karimi

Here, we describe the synthesis of the single amino acid chelator DOTAlaP and four of its derivatives. The corresponding gadolinium(III) complexes were investigated for their kinetic inertness, relaxometric properties at a range of fields and temperatures, ...

American Chemical Society2014