The purpose of this study was to combine a dual-Helmholtz (DH) transmit (Tx)-only coil and 12-channel receive (Rx)-only bended phased array (PA) coil to improve the magnetic flux (|B |) sensitivity in the superior-to-inferior (S-I) direction during human brain magnetic resonance imaging (MRI) at 7-T. The proposed coil combination was primarily implemented by electromagnetic (EM) simulation and compared with the 16-leg birdcage coil and 8-channel PA coil, which are generally used for the Tx- and Rx-only modes, respectively. The optimal coil combinations for the proposed structure were determined by |B | field calculations using the |B | and |B | fields, which are respectively the transmit and receive components of the |B | field. The coil performance was then evaluated by a bench test and 7-T MRI experiment. The results of the computational calculations indicated that the |B | field of the DH coil was distributed similarly to that of the 16-leg birdcage coil despite the fewer conducting legs of the former. However, the 12-channel Rx-only bended PA coil had clearly higher |B | profiles compared to the 8-channel PA coil. The results of the 7-T in vivo experiment showed that the proposed combination of the DH Tx-only coil and 12-channel Rx-only bended PA coil had better |B | field homogeneity in the sagittal slice as well as higher |B | field sensitivity during human brain MRI compared to an 8-channel Rx-only PA coil. SCANNING 38:515-524, © 2015 Wiley Periodicals, Inc.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/sca.21290 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Nuclear Condensates of WW Domain-Containing Adaptor With Coiled-Coil Regulate Mitophagy via Alternative Splicing.
Adv Sci (Weinh)
January 2025
State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.
Biomolecular condensates segregate nuclei into discrete regions, facilitating the execution of distinct biological functions. Here, it is identified that the WW domain containing adaptor with coiled-coil (WAC) is localized to nuclear speckles via its WW domain and plays a pivotal role in regulating alternative splicing through the formation of biomolecular condensates via its C-terminal coiled-coil (CC) domain. WAC acts as a scaffold protein and facilitates the integration of RNA-binding motif 12 (RBM12) into nuclear speckles, where RBM12 potentially interacts with the spliceosomal U5 small nuclear ribonucleoprotein (snRNP).
View Article and Find Full Text PDFA novel pulse-current waveform circuit for low-energy consumption and low-noise transcranial magnetic stimulation.
Front Neurosci
January 2025
School of Electronic Information and Communications, Huazhong University of Science and Technology, Wuhan City, China.
Introduction: Transcranial magnetic stimulation (TMS) is widely used for the noninvasive activation of neurons in the human brain. It utilizes a pulsed magnetic field to induce electric pulses that act on the central nervous system, altering the membrane potential of nerve cells in the cerebral cortex to treat certain mental diseases. However, the effectiveness of TMS can be compromised by significant heat generation and the clicking noise produced by the pulse in the TMS coil.
View Article and Find Full Text PDFUltrafast dynamic contrast-enhanced breast MRI with quantitative perfusion parameters in differentiating breast cancer: a study focusing on triple-negative and HER2 positive breast cancer.
Front Oncol
January 2025
Department of Radiology, the Second Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Background: In the realm of breast cancer diagnosis and treatment, accurately discerning molecular subtypes is of paramount importance, especially when aiming to avoid invasive tests. The updated guidelines for diagnosing and treating HER2 positive advanced breast cancer, as presented at the 2021 National Breast Cancer Conference and the Annual Meeting of the Chinese Society of Clinical Oncology, highlight the significance of this approach. A new generation of drug-antibody combinations has emerged, expanding the array of treatment options for HER2 positive advanced breast cancer and significantly improving patient survival rates.
View Article and Find Full Text PDFScale-Up of Continuous Metallaphotoredox Catalyzed C-O Coupling to a 10 kg-Scale Using Small Footprint Photochemical Taylor Vortex Flow Reactors.
Org Process Res Dev
January 2025
School of Chemistry, The University of Nottingham, University Park, Nottingham NG7 2RD, U.K.
We report the development and optimization of a scalable flow process for metallaphotoredox (Ir/Ni) C-O coupling, a mild and efficient approach for forming alkyl-aryl ethers, a common motif in medicinal and process chemistry settings. Time-resolved infrared spectroscopy (TRIR) highlighted the amine as the major quencher of the photocatalyst triplet excited state, along with the formation of an Ir(II) species that, in the presence of the Ni cocatalyst, has its lifetime shortened, suggesting reductive quenching of Ir(III)*, followed by reoxidation facilitated by the Ni cocatalyst. TRIR and batch reaction screening was used to develop conditions transferrable to flow, and many processing benefits of performing the reaction in flow were then demonstrated using a simple to construct/operate, small-footprint FEP coil flow reactor, including short (<10 min) space times and reduced catalyst loadings (down to 0.
View Article and Find Full Text PDFExploring the effect of natural deep eutectic solvents on zein: Structural and functional properties.
Curr Res Food Sci
December 2024
Department of Food Science and Technology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran.
This study evaluated the effects of chemical modification, including ethanol, acetic acid, and natural deep eutectic solvents (NADES), on the secondary and tertiary structures, hydrophobicity, free amine content, protein-protein interactions, and functional properties of zein. The NADES used included choline chloride: oxalic acid, choline chloride: urea, choline chloride: glycerol, and glucose: citric acid. The results reveal that the NADES system significantly altered zein's structures, as evidenced by Fourier transform infrared spectroscopy, fluorescence, and Ultraviolet-Visible Spectroscopy analysis.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!