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Related papers: Enhanced and Robust Contrast in CEST MRI: Saturati…

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Purpose: This work proposes a novel RF pulse design for parallel transmit (pTx) systems to obtain uniform saturation of semisolid magnetization for Magnetization Transfer (MT) contrast in the presence of transmit field ($B_1^+$)…

To simultaneously fit multiple-pool effects, spectrally selective 3D CEST imaging typically requires single-shot readouts to save time. However, to date, FLASH and EPI have been the primary pulse sequences used for this purpose. They suffer…

Purpose: To develop a model-based deep neural network for high-quality image reconstruction of undersampled multi-coil chemical exchange saturation transfer (CEST) data. Theory and Methods: Inspired by the variational network, the CEST…

Medical Physics · Physics 2023-05-26 Jianping Xu , Tao Zu , Yi-Cheng Hsu , Xiaoli Wang , Kannie W. Y. Chan , Yi Zhang

We present a framework for designing optimal optical pulses for the matter-wave splitting of a Bose-Einstein Condensate (BEC) under the influence of experimental inhomogeneities, so that the sample is transferred from an initial rest…

Optimization and Control · Mathematics 2024-03-01 Andre Luiz P. de Lima , Andrew K. Harter , Michael J. Martin , Anatoly Zlotnik

Purpose: ECG and respiratory-gated preclinical cardiac CEST-MRI acquisitions are difficult due to variable saturation recovery with T1, RF interference in the ECG signal, and offset-to-offset variation in Z-magnetization and cardiac phase…

Purpose: To develop and validate a framework for rapid, accurate, and reproducible whole-brain, multi-pool chemical exchange saturation transfer (CEST) imaging at 3T, addressing challenges of long acquisition times and confounding factors.…

Medical Physics · Physics 2025-09-16 Yupeng Wu , Siyuan Fang , Siyuan Wang , Caixia Fu , Jianqi Li

Purpose: Rapid 2D RF pulse design with subject specific $B_1^+$ inhomogeneity and $B_0$ off-resonance compensation at 7 T predicted from convolutional neural networks is presented. Methods: The convolution neural network was trained on half…

Purpose: To understand the influence of various acquisition parameters on the ability of CEST MR-Fingerprinting (MRF) to discriminate different chemical exchange parameters and to provide tools for optimal acquisition schedule design and…

Medical Physics · Physics 2019-11-04 Or Perlman , Kai Herz , Moritz Zaiss , Ouri Cohen , Matthew S. Rosen , Christian T. Farrar

Existing optimal control protocols for mitigating the effects of relaxation and/or RF inhomogeneity on broadband pulse performance are extended to the more difficult problem of designing robust, refocused, frequency selective excitation…

Instrumentation and Detectors · Physics 2015-06-03 Thomas E. Skinner , Naum I. Gershenzon , Manoj Nimbalkar , Steffen J. Glaser

Inhomogeneity, in its many forms, appears frequently in practical physical systems. Readily apparent in quantum systems, inhomogeneity is caused by hardware imperfections, measurement inaccuracies, and environmental variations, and…

Optimization and Control · Mathematics 2011-02-21 Justin Ruths , Jr-Shin Li

Endogenous chemical exchange saturation transfer (CEST) effects are always diluted by competing effects such as direct water proton saturation (spillover) and macromolecular magnetization transfer (MT). This leads to T2-and MT-shine-through…

Numerically optimised microwave pulses are used to increase excitation efficiency and modulation depth in electron spin resonance experiments performed on a spectrometer equipped with an arbitrary waveform generator. The optimisation…

Chemical Physics · Physics 2018-10-19 David L. Goodwin , William K. Myers , Christiane R. Timmel , Ilya Kuprov

This paper addresses the multivariable gradient-based extremum seeking control (ESC) subject to saturation. Two distinct saturation scenarios are investigated here: saturation acting on the input of the function to be optimized, which is…

Purpose: To develop a motion-robust and geometrically-accurate quantitative CEST approach using radial k-space sampling, locally low-rank reconstruction and neural network quantification. Methods: The acquisition schedule was generated via…

Medical Physics · Physics 2026-03-27 Ouri Cohen , Elizabeth J. Sutton , Robert J. Young , Ricardo Otazo

The past decade has demonstrated increasing interests in using optimal control based methods within coherent quantum controllable systems. The versatility of such methods has been demonstrated with particular elegance within nuclear…

Quantum Physics · Physics 2015-05-18 Ivan I. Maximov , Niels Chr. Nielsen , Julien Salomon , Gabriel Turinici

We propose a methodology to design optimal pulses for achieving quantum optimal control on molecular systems. Our approach constrains pulse shapes to linear combinations of a fixed number of experimentally relevant pulse functions. Quantum…

Quantum Physics · Physics 2015-10-28 Ruben D. Guerrero , Carlos A. Arango , Andres Reyes

We investigate the maximum signal to noise ratio per unit time that can be achieved for a spin 1/2 particle subjected to a periodic pulse sequence. Optimal control techniques are applied to design the control field and the position of the…

Quantum Physics · Physics 2015-06-22 M. Lapert , E. Assémat , S. J. Glaser , D. Sugny

Numerically we simulate the effect of optimized coherent control pulses with a finite duration on a qubit in a bath of spins. The pulses of finite duration are compared with ideal instantaneous pulses. In particular, we show that properly…

Quantum Physics · Physics 2008-08-26 P. Karbach , S. Pasini , G. S. Uhrig

A magnitude-least-squares radiofrequency pulse design algorithm is reported which uses interleaved exact and stochastically-generated inexact updates to escape local minima and find low-cost solutions. Inexact updates are performed using a…

Medical Physics · Physics 2024-07-23 Jonathan B. Martin , Charlotte R. Sappo , Benjamin M. Hardy , William A. Grissom

We formulate a robust optimal control algorithm to synthesize minimum energy pulses that can transfer a cold atom system into various momentum states. The algorithm uses adaptive linearization of the evolution operator and sequential…

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