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The involvement of the human amygdala in emotion-related processing has been studied using functional magnetic resonance imaging (fMRI) for many years. However, despite the amygdala being comprised of several subnuclei, most studies investigated the role of the entire amygdala in processing of emotions. Here we combined a novel anatomical tracing protocol(More)
PURPOSE The dependence of diffusion tensor imaging (DTI) eigenvalues and fractional anisotropy (FA) on short diffusion times was investigated using oscillating gradient spin echo (OGSE) and pulsed gradient spin echo (PGSE) DTI in the human brain in vivo. THEORY AND METHODS DTI was performed in seven healthy volunteers at 4.7 Tesla (T) with b = 300 s/mm(2)(More)
PURPOSE An acquisition method that does not increase scan time or specific absorption rate is investigated for reducing the deleterious effects of cerebrospinal fluid (CSF) partial volume effects on diffusion tensor imaging (DTI) tractography. It is based on using a shorter repetition time (TR) by means of slice acquisition re-ordering to reduce the signal(More)
BACKGROUND AND PURPOSE Diffusion-weighted imaging (DWI) of tissue water is a sensitive and specific indicator of acute brain ischemia, where reductions of the diffusion of tissue water are observed acutely in the stroke lesion core. Although these diffusion changes have been long attributed to cell swelling, the precise nature of the biophysical mechanisms(More)
PURPOSE A readout-segmented method for acquiring robust GRAPPA calibration data for echo-planar imaging (EPI) was proposed and compared with two previous methods, including the gold standard interleaved approach and a single shot method with halved phase encode resolution. THEORY AND METHODS The readout-segmented and single shot techniques acquire(More)
Concomitant gradient fields are transverse magnetic field components that are necessarily present to satisfy Maxwell's equations when magnetic field gradients are utilized in magnetic resonance imaging. They can have deleterious effects that are more prominent at lower static fields and/or higher gradient strengths. In diffusion tensor imaging schemes that(More)
We present a material composite consisting of randomly oriented elements governed by non-resonant interactions. By exploiting near-field plasmonic interaction in a dense ensemble of subwavelength-sized dielectric and metallic particles, we reveal that the group refractive index of the composite can be increased to be larger than the effective refractive(More)
A class of active terahertz devices that operate via particle plasmon oscillations is introduced for ensembles consisting of ferromagnetic and dielectric micro-particles. By utilizing an interplay between spin-orbit interaction manifesting as anisotropic magnetoresistance and the optical distance between ferromagnetic particles, a multifaceted paradigm for(More)
PURPOSE To create a B0 map and correct for off-resonance with minimal scan time increase for two-dimensional (2D) or 3D non-Cartesian acquisitions. METHODS Rewinding trajectories that bring the zeroth gradient moment to zero every repetition time (TR) were used to estimate the off-resonance with a center-out 3D cones trajectory, which required an increase(More)