Longitudinal wall motion of the common carotid artery can be assessed by velocity vector imaging

Velocity vector imaging (VVI) is novel ultrasound image analysis software, enabling simultaneous evaluation of longitudinal and radial tissue motion. This study aimed to investigate the possible usefulness of VVI in evaluating the longitudinal vessel wall movement of the common carotid artery (CCA). Sixteen healthy volunteers and 16 patients with established coronary artery disease (CAD) were included in the study. CCA was scanned and standard B-mode ultrasound images were analysed off-line with VVI. In healthy volunteers, total longitudinal displacements (tLoD) of the right and left CCA were similar, as were the movements of the near- and far wall of the right CCA. The CAD group showed significantly lower tLoD compared to the healthy volunteers (0·543 ± 0·394 versus 0·112 ± 0·074, P<0·0001). VVI is a highly feasible technique in assessing longitudinal CCA wall motion, which may be of potential relevance as a novel vascular biomarker

Guiding On-Chip Optical Beams without Diffraction in a Rod- Type Silicon Photonic Crystal

Guiding on-chip optical beams without diffraction is very important in the future’s all-photonic circuits. Herein, both theoretically and experimentally, we study an all-angle quasi-self-collimation phenomenon occurring in photonic crystals composed of silicon nanorods. When the all-angle quasi-self-collimation phenomenon occurs, the optical beams can be incident onto such photonic crystals from directions covering a wide range (extremely close to all-angle) of incident angles direction and become highly localized along even a single array of rods, which finally achieve results in the narrow-beam propagation without divergence. The propagation length is expected to be 1000 times larger than the wavelength of light. Theoretically, it is shown that such all-angle quasi-self-collimation phenomenon is owing to the symmetry change of the lattice of photonic crystals. By changing the symmetry of a photonic crystal to straighten the isofrequency contours, the photonic crystal shows the all-angle quasi-self-collimation effect. Experimentally, we show the observation of all-angle quasi-self-collimation phenomenon occurring in a rod-type silicon photonic crystal fabricated on by patterning a silicon-on-insulator (SOI) wafer. The experimentally observed propagation length is more than 0.4 mm over the telecom wavelength range, even though at large angle of incidence, which is a relatively large length scale for on-chip optical interconnection

A simplified model of jet power from active galactic nuclei

Aims. A simplified model of jet power from active galactic nuclei is proposed in which the relationship between jet power and disk luminosity is discussed by combining disk accretion with two mechanisms of extracting energy magnetically from a black hole accretion disk, i.e., the Blandford-Payne (BP) and the Blandford-Znajek (BZ) processes. Methods. By including the BP process into the conservation laws of mass, angular momentum and energy, we derive the expressions of the BP power and disk luminosity, and the jet power is regarded as the sum of the BZ and BP powers. Results. We find that the disk radiation flux and luminosity decrease because a fraction of the accretion energy is channelled into the outflow/jet in the BP process. It is found that the dominant cooling mode of the accretion disk is determined mainly by how the poloidal magnetic field decreases with the cylindrical radius of the jet. By using the parameter space we found, which consists of the black hole spin and the self-similar index of the configuration of the poloidal magnetic field frozen in the disk, we were able to compare the relative importance of the following quantities related to the jet production: (1) the BP power versus the disk luminosity, (2) the BP power versus the BZ power, and (3) the jet power versus the disk luminosity. In addition, we fit the jet power and broad-line region luminosity of 11 flat-spectrum radio quasars (FSRQs) and 17 steep-spectrum radio quasars (SSRQs) based on our model.Comment: accepted by A&

Possible Way to Synthesize Superheavy Element Z=117

Within the framework of the dinuclear system model, the production of superheavy element Z=117 in possible projectile-target combinations is analyzed systematically. The calculated results show that the production cross sections are strongly dependent on the reaction systems. Optimal combinations, corresponding excitation energies and evaporation channels are proposed in this letter, such as the isotopes ^{248,249}Bk in ^{48}Ca induced reactions in 3n evaporation channels and the reactions ^{45}Sc+^{246,248}Cm in 3n and 4n channels, and the system ^{51}V+^{244}Pu in 3n channel.Comment: 10 pages, 4 figures, 1 tabl

Exposure to various abscission-promoting treatments suggests substantial ERF subfamily transcription factors involvement in the regulation of cassava leaf abscission

AP2/ERF genes that exhibited the same expression patterns during ethylene and water-deficit stress treatments. (XLS 19 kb