Effect of geometrical structure on transport properties of silicene nanoconstrictions*

We study electrical modulation of transport properties of silicene nanoconstrictions with different geometrical structures. We investigate the effects of the position and width of the central scattering region on the conductance with increasing Fermi energy. It is found that the conductance significantly depends on the position and the width of the nanoconstriction. Interestingly, the symmetrical structure of the central constriction region can induce a resonance effect and significantly increase the systemʼs conductance. We also propose a novel two-channel structure with an excellent performance on the conductance compared to the one-channel structure with the same total width. Such geometrically-induced conductance modulation of silicene nanostructures can be achieved in practice via current nanofabrication technology.

Vagal stimulation in heart failure

Vagal nerve stimulation (VNS) has a strong pathophysiological rationale as a potentially beneficial treatment for heart failure with reduced ejection fraction. Despite several promising preclinical studies and pilot clinical studies, the two large, controlled trials—NECTAR-HF and INOVATE-HF—failed to demonstrate the expected benefit. It is likely that clinical application of VNS in phase III studies was performed before a sufficient degree of understanding of the complex pathophysiology of autonomic electrical modulation had been achieved, therefore leading to an underestimation of its potential benefit. More knowledge on the complex dose–response issue of VNS (i.e., pulse amplitude, frequency, duration and duty cycle) has been gathered since these trials and a new randomized study is currently underway with an adaptive design and a refined approach in an attempt to deliver the proper dose to a more selected group of patients.

Applications of AOTF Spectrometers in In Situ Lunar Measurements

Spectrometers based on acousto-optic tunable filters (AOTFs) have several advantages, such as stable temperature adaptability, no moving parts, and wavelength selection through electrical modulation, compared with the traditional grating and Fourier transform spectrometers. Therefore, AOTF spectrometers can realize stable in situ measurement on the lunar surface under wide temperature ranges and low light environments. AOTF imaging spectrometers were first employed for in situ measurement of the lunar surface in the Chinese Chang’e project. The visible and near-infrared imaging spectrometer and the lunar mineralogical spectrometer have been successfully deployed on board the Chang’e-3/4 and Chang’e-5 missions. In this review, we investigate the performance indicators, structural design, selected AOTF performance parameters, data acquisition of the three lunar in situ spectral instruments used in the Chang’e missions. In addition, we also show the scientific achievement of lunar technology based on in situ spectral data.