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Showing 1 to 20 of 20 for “"129Xe"”.
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Improved Visualization and Quantification for Hyperpolarized 129Xe MRI
… years, the introduction of hyperpolarized (HP) 129Xe magnetic resonance imaging (MRI) into clinical research has provided a robust and non-invasive 3D imaging technique, capable of both high-resolution imaging of pulmonary ventilation and gas exchange. Notably, gas exchange imaging is enabled by …
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Eosinophilic Asthma Response to Therapy: 129Xe Magnetic Resonance Imaging and Computed Tomography
… of this thesis was to use hyperpolarized 129Xe MRI and chest CT to evaluate pulmonary function and structure following continuous anti-IL-5Rα therapy and to compare with pre-treatment measurements to better our understanding of the mechanisms responsible for improved asthma control and …
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Translational Imaging of Pulmonary Gas-Exchange Using Hyperpolarized 129Xe Magnetic Resonance Imaging
<p>The diagnosis and treatment of pulmonary diseases still rely on pulmonary function tests that offer archaic or insensitive biomarkers of lung structure and function. As a consequence, chronic obstructive pulmonary disease is the third leading cause of death in the US, and the hospitalization …
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Dynamic 129Xe Magnetic Resonance Spectroscopy: Development and Application in Diverse Cardiopulmonary Diseases
… receive optimal treatment. </p><p>Hyperpolarized 129Xe MR imaging (MRI) and spectroscopy (MRS) have emerged as a powerful tool for assessing the pulmonary environment due xenon exhibiting distinct chemical shifts as it diffuses from the airspaces, through the alveolar membrane, and interacts with …
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Using High-Powered, Frequency-Narrowed Lasers For Rb/129Xe and Cs/129Xe Spin-Exchange Optical Pumping To Achieve Improved Production of Highly Spin-Polarized Xenon For Use In Magnetic Resonance Applications
<p>Nuclear magnetic resonance (NMR) spectroscopy has been extensively used to investigate numerous systems of interest, ranging from collections of molecules to living organisms. However, NMR suffers from one key drawback: an inherent lack of detection sensitivity, as compared to other common forms …
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Clinical-Scale Hyperpolarization of 129Xe and 131Xe via Stopped-Flow Spin Exchange Optical Pumping
… >0.8 L of hyperpolarized gas per SEOP cycle with 129Xe polarization values of ~30-90% (depending on the xenon density). Multidimensional data maps were created over various temperatures, gas mixes, and laser powers; the results are used to guide optimal performance and describe the conditions that …
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Hyperpolarized xenon-129 production and applications
<p>Hyperpolarized 3He and 129Xe were initially developed and used in the nuclear physics community. Lately they are primarily used in Medical Resonance Imaging (MRI). Although first MRI polarized gas images were acquired using 129Xe, the research community has focused mostly on 3He, due to the …
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NMR mit thermischpolarisiertem und hyperpolarisiertem Xenon
… regeneration process could be observed by using 129Xe-NMR spectroscopy. The measurement of the longitudinal and the transversal relaxation times of xenon atoms in mineral oil containing natural-rubber elastomers (NR) obtained more characteristic results compared to 1H relaxometry measurements, …
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Fundamental studies and applications for the development of novel MRI contrast agents: Hyperpolarized xenon-129 and superparamagnetic iron oxide nanoparticles
… types of MRI contrast agents: hyperpolarized 129Xe gas and superparamagnetic iron oxide nanoparticles (SPIONs). The largest `Achilles' Heel' of MR techniques is their inherent lack of detection sensitivity due to the exceedingly small magnitude of the nuclear spins, giving rise to small …
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Cryptophane Derivatives as Gas Sensors and Hyperpolarized Xenon-129 Biosensors
… applications: encapsulation of noble gases, 129Xe NMR biosensing for cancer detection, and the construction of molecular devices. A new water-soluble organic host molecule, tris-(triazole ethylamine) cryptophane, was synthesized for noble gas detection. This host was found to bind xenon with …
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Xenon NMR with spectroscopic, spatial, and temporal resolution
129Xe NMR has found many applications in material sciences and medicine because of two useful properties of Xenon atoms for NMR: the sensitivity to their environment due to their highly polarizable electron cloud, which results in a wide range of chemical shifts, and the ability of being …
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Hyperpolarized Nuclei for NMR Imaging and Spectroscopy – Methodology and model studies of lung and vascular function
… investigated, using three hyperpolarized nuclei: 129Xe, 13C, and 3He. In addition, practical aspects regarding the handling and utilization of hyperpolarized substances were evaluated. The potential of angiography using echo-planar imaging (EPI) was investigated using dissolved 129Xe in a phantom …
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Microporous Organically Pillared Layered Silicates (MOPS) with tunable Functionality
… Spektroskopie in Kombination mit hochauflösender 129Xe MAS NMR Spektroskopie untersucht. Weitere temperaturabhängige ein- und zweidimensionale „wide-line“ 129Xe NMR Untersuchungen zusammen mit Argon- und Xenon-Physisorptionsmessungen wurden durch-geführt. Eine homogene Verteilung des …
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Advanced NMR analysis of polymers and biomolecules
… wideline spectroscopy, and thermally polarized 129Xe has been investigated. Such a study using a combination of different advanced NMR methods was never reported before. A coherent picture that correlates the chemical sites and molecular dynamics resulted from this investigation. For the first …
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Science and history explored by nuclear magnetic resonance
… electrical conductivity of PEM. Hyperpolarized 129Xe NMR spectroscopy was successfully applied for monitoring the free radical polymerization reactions of methyl methacrylate, methyl acrylate and the copolymerization of methyl methacrylate and methyl acrylate. The observation of Xe chemical …
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Hyperpolarized Xenon-129 Magnetic Resonance Imaging of Functional Lung Microstructure
<p>Hyperpolarized 129Xe (HXe) is a non-invasive contrast agent for lung magnetic resonance imaging (MRI), which upon inhalation follows the functional pathway of oxygen in the lung by dissolving into lung tissue structures and entering the blood stream. HXe MRI therefore provides unique …
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Synthese von immobilisierten Übergangsmetall-Salen-Komplexen, deren Charakterisierung und Einsatz in der enantioselektiven Epoxidierung von 1,2-Dihydronaphthalin
… by measuring the chemical shift of adsorbed 129Xe. A poresize distribution was calculated from measurements of the freezing point depression of water that is occluded inside the pores. The modified zeolites were used as carrier materials for chiral transitionmetal-salen-complexes. The …
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Making Nuclear Magnetic Hyperpolarization Practical through Storage in Disconnected Eigenstates
… An example case of hyperpolarized 3He and 129Xe diffusing through lung tissue is examined. In particular a Monte Carlo simulation tool, combined with a magnetic field map of the inhomogeneous field created by mouse lung tissue, is used to determine the dephasing rate of hyperpolarized 3He …
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Design of Robust Heterogeneous Catalysts for Sustainable Chemistry
… TGA, N2-physisorption and TEM. Hyperpolarized 129Xe NMR was used to study the effect of nickel loading and annealing time on pore structure. The microporous materials showed good thermal stability and activity in selective hydrogenation of aryl acetylenes but as polymer to ceramic conversion …
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NOVEL EXPERIMENTAL APPROACHES AND THEORETICAL MODELS FOR IMPROVING SENSITIVITY AND INFORMATION CONTENT OF NMR AND MRI SPECTROSCOPY
… effect). The SPINOE enhancements, along with the 129Xe NMR spectra, provide information about the interaction of the Xe-cryptophane complex (variants of which are now used in so-called xenon biosensors). This was our first in-house successful application of hyperpolarized xenon as a signal source …