Dynamic Real-Time Magnetic Resonance at Very Low Magnetic Fields

10.26434/chemrxiv.12911156.v1 ◽

2020 ◽

Author(s):

Sergey Korchak ◽

Anil P. Jagtap ◽

Stefan Gloeggler

Keyword(s):

Magnetic Resonance ◽

Magnetic Fields ◽

Real Time ◽

Cancer Metabolism ◽

State Of The Art ◽

Medical Diagnostics ◽

Detection Sensitivity ◽

Enzymatic Reactions ◽

Large Signal ◽

Biological Studies

The phenomenon of nuclear magnetic resonance (NMR) is widely applied in biomedical and biological science to study structures and dynamics of proteins and their reactions. Despite its impact, NMR is an inherently insensitive phenomenon and has driven the field to construct spectrometers with increasingly higher magnetic fields leading to more detection sensitivity. Here, we are demonstrating that enzymatic reactions can be followed in real-time at millitesla fields, 1000-fold lower than state-of-the-art spectrometers. This requires signal-enhancing samples via hyperpolarization. Within seconds, we have enhanced the signals of 2- 13Cpyruvate, an important metabolite to probe cancer metabolism, in 22 mM concentrations (up to 10.1%±0.1% polarization) and show that such a large signal allows for the real-time detection of enzymatic conversion of pyruvate to lactate. This development paves the pathways for biological studies in portable and affordable NMR systems with a potential for medical diagnostics. <br>

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Signal-enhanced real-time magnetic resonance of enzymatic reactions at millitesla fields

Chemical Science ◽

10.1039/d0sc04884d ◽

2021 ◽

Vol 12 (1) ◽

pp. 314-319

Author(s):

Sergey Korchak ◽

Anil P. Jagtap ◽

Stefan Glöggler

Keyword(s):

Magnetic Resonance ◽

Real Time ◽

High Field ◽

State Of The Art ◽

Enzymatic Reactions

We demonstrate that metabolism can be monitored in real-time with magnetic resonance at milli-tesla fields that are 1000 fold lower than state-of-the-art high field spectrometers.

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Nuclear magnetic resonance microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156110 ◽

1989 ◽

Vol 47 ◽

pp. 828-829

Author(s):

Paul C. Lauterbur

Keyword(s):

Magnetic Field ◽

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Magnetic Fields ◽

Signal To Noise ◽

Field Gradients ◽

Useful Signal ◽

Magnetic Field Gradients ◽

Observation Times ◽

Nuclear Magnetic

Nuclear magnetic resonance imaging can reach microscopic resolution, as was noted many years ago, but the first serious attempt to explore the limits of the possibilities was made by Hedges. Resolution is ultimately limited under most circumstances by the signal-to-noise ratio, which is greater for small radio receiver coils, high magnetic fields and long observation times. The strongest signals in biological applications are obtained from water protons; for the usual magnetic fields used in NMR experiments (2-14 tesla), receiver coils of one to several millimeters in diameter, and observation times of a number of minutes, the volume resolution will be limited to a few hundred or thousand cubic micrometers. The proportions of voxels may be freely chosen within wide limits by varying the details of the imaging procedure. For isotropic resolution, therefore, objects of the order of (10μm) may be distinguished.Because the spatial coordinates are encoded by magnetic field gradients, the NMR resonance frequency differences, which determine the potential spatial resolution, may be made very large. As noted above, however, the corresponding volumes may become too small to give useful signal-to-noise ratios. In the presence of magnetic field gradients there will also be a loss of signal strength and resolution because molecular diffusion causes the coherence of the NMR signal to decay more rapidly than it otherwise would. This phenomenon is especially important in microscopic imaging.

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Current Issues: Advanced Digital Technology for Supervising Graduate Clinicians

Perspectives on Administration and Supervision ◽

10.1044/aas20.1.9 ◽

2010 ◽

Vol 20 (1) ◽

pp. 9-13 ◽

Cited By ~ 2

Author(s):

Glenn Tellis ◽

Lori Cimino ◽

Jennifer Alberti

Keyword(s):

Real Time ◽

Digital Technology ◽

Clinical Training ◽

State Of The Art ◽

Clinical Skills ◽

Slow Motion ◽

Video Capture ◽

Microsoft Excel ◽

Clinical Supervisors ◽

Training And Supervision

Abstract The purpose of this article is to provide clinical supervisors with information pertaining to state-of-the-art clinic observation technology. We use a novel video-capture technology, the Landro Play Analyzer, to supervise clinical sessions as well as to train students to improve their clinical skills. We can observe four clinical sessions simultaneously from a central observation center. In addition, speech samples can be analyzed in real-time; saved on a CD, DVD, or flash/jump drive; viewed in slow motion; paused; and analyzed with Microsoft Excel. Procedures for applying the technology for clinical training and supervision will be discussed.

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Semantic Edge Detection for Tracking Vocal Tract Air-Tissue Boundaries in Real-Time Magnetic Resonance Images

10.21437/interspeech.2017-1580 ◽

2017 ◽

Cited By ~ 12

Author(s):

Krishna Somandepalli ◽

Asterios Toutios ◽

Shrikanth S. Narayanan

Keyword(s):

Magnetic Resonance ◽

Edge Detection ◽

Real Time ◽

Vocal Tract ◽

Magnetic Resonance Images

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Articulatory Synthesis Based on Real-Time Magnetic Resonance Imaging Data

10.21437/interspeech.2016-596 ◽

2016 ◽

Cited By ~ 5

Author(s):

Asterios Toutios ◽

Tanner Sorensen ◽

Krishna Somandepalli ◽

Rachel Alexander ◽

Shrikanth S. Narayanan

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Real Time ◽

Imaging Data ◽

Resonance Imaging ◽

Magnetic Resonance Imaging Data ◽

Articulatory Synthesis

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Biological NMR Spectroscopy

10.1093/oso/9780195094688.001.0001 ◽

1997 ◽

Keyword(s):

Nuclear Magnetic Resonance ◽

Nmr Spectroscopy ◽

Magnetic Resonance ◽

Magnetic Resonance Spectroscopy ◽

State Of The Art ◽

Critical Assessment ◽

Resonance Spectroscopy ◽

History Of ◽

Structure Of Proteins

This book presents a critical assessment of progress on the use of nuclear magnetic resonance spectroscopy to determine the structure of proteins, including brief reviews of the history of the field along with coverage of current clinical and in vivo applications. The book, in honor of Oleg Jardetsky, one of the pioneers of the field, is edited by two of the most highly respected investigators using NMR, and features contributions by most of the leading workers in the field. It will be valued as a landmark publication that presents the state-of-the-art perspectives regarding one of today's most important technologies.

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Real-Time Path Planning with Virtual Magnetic Fields

IEEE Robotics and Automation Letters ◽

10.1109/lra.2021.3063992 ◽

2021 ◽

pp. 1-1

Author(s):

Majda Moussa ◽

Giovanni Beltrame

Keyword(s):

Magnetic Fields ◽

Path Planning ◽

Real Time ◽

Time Path

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Self-Regulating Demand and Supply Equilibrium in Joint Simulation of Travel Demand and a Ride-Pooling Service

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198121997140 ◽

2021 ◽

pp. 036119812199714

Author(s):

Gabriel Wilkes ◽

Roman Engelhardt ◽

Lars Briem ◽

Florian Dandl ◽

Peter Vortisch ◽

...

Keyword(s):

Real Time ◽

Travel Demand ◽

State Of The Art ◽

Choice Model ◽

Mode Choice ◽

Attractive Alternative ◽

Full Potential ◽

Demand Model ◽

Modeling Framework ◽

Demand And Supply

This paper presents the coupling of a state-of-the-art ride-pooling fleet simulation package with the mobiTopp travel demand modeling framework. The coupling of both models enables a detailed agent- and activity-based demand model, in which travelers have the option to use ride-pooling based on real-time offers of an optimized ride-pooling operation. On the one hand, this approach allows the application of detailed mode-choice models based on agent-level attributes coming from mobiTopp functionalities. On the other hand, existing state-of-the-art ride-pooling optimization can be applied to utilize the full potential of ride-pooling. The introduced interface allows mode choice based on real-time fleet information and thereby does not require multiple iterations per simulated day to achieve a balance of ride-pooling demand and supply. The introduced methodology is applied to a case study of an example model where in total approximately 70,000 trips are performed. Simulations with a simplified mode-choice model with varying fleet size (0–150 vehicles), fares, and further fleet operators’ settings show that (i) ride-pooling can be a very attractive alternative to existing modes and (ii) the fare model can affect the mode shifts to ride-pooling. Depending on the scenario, the mode share of ride-pooling is between 7.6% and 16.8% and the average distance-weighed occupancy of the ride-pooling fleet varies between 0.75 and 1.17.

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