The results showed that the proposed WLC could be an alternative to standard cable-connected receive coils in clinical magnetic resonance imaging. As an example, with no cable connection, the WLC allowed wrist imaging on a 1.5 T clinical machine using a full-body BC for transmitting and receive with the desired signal-to-noise ratio, image quality, and safety.

The objective of this study is to develop, test and validate a fully automatic, deep learning-based segmentation method for the wrist joint cartilage in magnetic resonance images. The study was conducted in 8 healthy volunteers and 3 patients with wrist joint diseases. 3D MRI datasets (20 in total) were acquired at 1.5T using a VIBE sequence. Wrist cartilage was segmented on coronal slices by a clinician and the convolutional neural network (CNN) was trained, developed and tested using the corresponding segmented masks. For an inter and intra observer study wrist cartilage was segmented by three observers once and twice by one observer on a dataset of 20 central coronal slices. Performance of the CNN was compared quantitatively to the manual segmentations using the concordance and the Sørensen-Dice similarity coefficients (DSC). Cartilage segmentations obtained with the CNN showed a substantial agreement with the manual segmentations for the whole wrist joint (DSC = 0.73) and a good agreement (DSC = 0.81) for the central coronal slices. The inter-and intra-observer concordance indices for manual segmentations were 0.55 and 0.85, respectively. The concordance index of the CNN-based segmentation was 0.69 when compared to the manual segmentations. The fully automatic deep-learning based segmentation of the wrist cartilage showed a high concordance with the manual measurements. It could be applied to determine an automatic, quantitative metric in clinical wrist cartilage studies.

The temperature dependencies of (13)C NMR relaxation rates in [bmim]PF6 ionic liquid have been measured and the characteristic times (τc) for the cation reorientation have been recalculated. We found the origin of the incorrect τc temperature dependencies that were earlier reported for ring carbons in a number of imidazolium-based ILs. After a correction of the approach (13)C T1, the relaxation data allowed us to obtain the characteristic times for an orientation mobility of each carbon, and a complicated experiment, such as NOE, was not required. Thus the applicability of (13)C NMR relaxation rate measurements to the calculation of the characteristic times for reorientation of all the carbons of the [bmim](+) cation was confirmed and our findings have shown that a (13)C NMR relaxation technique allowed its application to ionic liquids to be equally successful as for other liquid systems.

Metasurfaces is a rapidly developing area with quite many prospective applications in light manipulation, aberration-free optical imaging, and security. One potential area where metasurface approaches may provide a valuable contribution is medical imaging. In this paper, a novel subwavelength metasurface-inspired resonator design is presented, which is employed to enhance the sensitivity of magnetic resonance imaging (MRI). To this end, the resonator is formed by an array of capacitively loaded telescopic wires is placed inside the scanner in a close proximity of the studied object. The telescopic design of the structure permits to mechanically adjust its eigenmode resonance frequency to the operational frequency of a 1.5T MRI machine, thus making it possible to enhance and redistribute the radiofrequency magnetic field of an available radiofrequency coil in the region of interest and therefore significantly increase the sensitivity of the receiver. status solidi physica a Metasurfaces www.pss-a.com