Results 161 to 170 of about 959,350 (322)

An Adaptive Metasurface for Adjustable Magnetic Resonance Imaging Enhancement at 3 T and 7 T: A Feasibility Study

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose Ultra‐high field (≥ 7 T) and 3 T MRI suffer from B1+ inhomogeneity and signal loss. Conventional metasurfaces that mitigate B1+ inhomogeneity and improve image SNR are “fixed” in nature and designed for a single Larmor frequency. This study demonstrates the feasibility of an adaptive metasurface utilizing voltage‐controlled capacitors ...
Paul S. Jacobs, Pradnya Narvekar, Neil E. Wilson, Gabor Mizsei, Wyger Brink, John A. Detre, Mark A. Elliott, Ravinder Reddy   +7 more
wiley   +1 more source

Iterative Navigator‐Based Retrospective Motion Correction for Multi‐Shot Brain MR Elastography and Evaluation of Single‐Shot Post‐Reconstruction Correction

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose Brain MR elastography (MRE) is uniquely sensitive to subject motion, as even small phase deviations can produce large errors in the mechanical properties estimated. Existing motion correction strategies have not been validated for MRE and are often incompatible with complex multi‐shot or joint temporal reconstructions.
Zhuoyu Shi, Alex Michael Cerjanic, Grace McIlvain   +2 more
wiley   +1 more source

Factors Influencing Lesion Formation During Radiofrequency Catheter Ablation

Indian Pacing and Electrophysiology Journal, 2003
In radiofrequency (RF) ablation, the heating of cardiac tissue is mainly resistive. RF current heats cardiac tissue and in turn the catheter electrode is being heated.
Olaf J. Eick
doaj  

Rotating Frame Spin‐Lock Cardiac MRI Method at 9.4 T Can Characterize Diffuse Fibrosis in Progressing Hypertensive Heart Disease in Mice

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose This study aimed to investigate the applicability of rotating frame spin‐lock continuous wave (CW) T1ρ and relaxation along a fictitious field with Rank 2 (RAFF2) methods complementary to native T1 and late gadolinium enhancement (LGE) for cardiac magnetic resonance imaging (CMRI) of diffuse fibrosis in mice with advancing hypertensive
Riku Kiviluoto, Diana Törmä, Ahmed Tawfek, Aleksi J. Leikas, Eetu Räihä, Mari Merentie, Anna‐Kaisa Ruotsalainen, Seppo Ylä‐Herttuala, Elias Ylä‐Herttuala   +8 more
wiley   +1 more source

Combined Metasurface and Metamaterial Passive Transmit Lens and Receive Array for 3 T

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose Metasurfaces (MSs) and metamaterials (MMs) can reduce transmit field nulls caused by wavelength effects at higher MR field strengths. We present a layered MM and MS resonant structure that improves transmit field performance when used as a combined slab (i.e., the metaslab), while also operating as a receive array.
Adam M. Maunder, Lauren P. Smart, Léo J. E. Rémillard, Ashwin K. Iyer, Nicola De Zanche   +4 more
wiley   +1 more source

RF-Squad: A radiofrequency simulator for quantum dot arrays

Spins in semiconductor quantum dots offer a scalable approach to quantum computing; however, precise control and efficient readout of large quantum dot arrays remain challenging, mainly due to the hyperdimensional voltage space required for tuning multiple gates per dot.
Murphy, Tara, Brlec, Katarina, Oakes, Giovanni, Peri, Lorenzo, Sirringhaus, Henning, Moss, Henry, Zalba, M. Fernando Gonzalez, Wise, David   +7 more
openaire   +2 more sources

Serum elemental profile‐based machine learning models for Alzheimer's disease identification and cognitive score prediction

Neuroprotection, EarlyView.
Serum elemental profiling combined with machine learning supports exploratory Alzheimer's disease (AD) identification and cognitive score prediction. In this retrospective cross‐sectional study, 874 participants from the BANC‐PUMC, including cognitively normal controls and patients with AD, were analyzed.
Haotian Liu, Xinnan Liu, Yashuang Chen, Meng Pan, Ying Fu, Chao Ma, Wei Ge   +6 more
wiley   +1 more source

Alteration of functional connectivity and network properties after stereo-electroencephalography guided radiofrequency thermocoagulation

Chinese Neurosurgical Journal
Background Stereo-electroencephalography guided radiofrequency thermocoagulation (RF-TC) aims at changing epileptogenic networks to achieve therapeutic purpose. However, the functional connectivity mechanism of RF-TC remains unknown.
Danyi Shen, Lanling Zhou, Nianshun Liao, Sixun Yu, Xin Chen, Haifeng Shu   +5 more
doaj   +1 more source

Multi‐Scale Magnetically Controlled Soft Matter Robots for Tissue Interfacing Applications

SmartBot, EarlyView.
Magnetically controlled soft matter robots (MSMRs) integrate remote magnetic control with soft matter adaptability for minimally invasive biomedical tasks at tissue interfaces across multiple scales. This review examines the interaction mechanisms between MSMRs and tissue interfaces, with MSMRs classified into five categories according to their ...
Wenxin Lian, Yan Zhou, Dianhong Zhang, Yuanwen Liang, Zihao Tang, Zhuo Chen, Qichen Hong, Jiangfan Yu, Chi Zhang, Xiaopu Wang   +9 more
wiley   +1 more source

Plasma Treatment on 1D Tungsten Disulfide Carbon Core–Shell Composites for Improved Performance in the Hydrogen Evolution Reaction

Small, EarlyView.
RF Ar plasma exposure selectively activates carbon‐coated WS2 nanotubes, substantially lowering the HER overpotential while preserving an ordered, conductive framework. A subsequent D2 plasma step produces interlayer expansion and greater structural disorder, reducing activity.
Asmita Dutta, Hani Porat, Aneena Lal, Arie Borenstein, Alla Zak, Gennady Makrinich, Alex Laikhtman   +6 more
wiley   +1 more source