Effect of mediastinal lymph nodes sampling in patients with clinical stage I non-small cell lung cancer

Objective : Systematic nodal dissection has been recommended for patients with resectable non-small cell lung cancer because of its staging accuracy. However, in patients with clinical stage I non-small cell lung cancer whether systematic nodal dissection provides more benefits than mediastinal lymph node sampling or not is controversial. In this retrospective study, we evaluated the effect of mediastinal lymph node sampling in patients with clinical stage I NSCLC. Methods : One hundred and nineteen consecutive patients with clinical stage I NSCLC, who underwent curative operation between January 1994 and December 2000, were retrospectively reviewed (dissection group = 58 : sampling group= 61). Systematic nodal dissection was defined as complete removal of mediastinal lymph node, and mediastinal lymph node sampling was defined as removal of lymph node levels 3, 4, and 7 for right-sided tumors and levels 5, 6, and 7 for left-sided tumors. Results : The total number of removed mediastinal lymph nodes in patients who underwent systematic nodal dissection was 22.1±9.7, which was significantly higher than that in patients who underwent mediastinal lymph node sampling of 11.4±7.0 (p<0.001). Postoperatively N2 disease was detected in 8 patients (13.8%) in the dissection group and 7 (11.5%) in the sampling group. After the median follow up of 79 months, the cancer specific survival rate at 5 year was 78.0% in the dissection group and 76.2% in the sampling group (p = 0.60). Conclusions : Mediastinal lymph node sampling showed the similar effect to systematic nodal dissection in patients with clinical stage I non-small cell lung cancer

Along-dip segmentation of the 2011 off the Pacific coast of Tohoku Earthquake and comparison with other megathrust earthquakes

The 11 March 2011 Tohoku Earthquake ruptured the interplate boundary off-shore of east Japan, with fault displacements of up to 40 m and a rupture duration of 150-160 s. W-phase inversion indicates a moment of 3.9 × 1022 N m (Mw 9.0) and a centroid time of 71 s. We invert teleseismic P waves and broadband Rayleigh wave observations with high-rate GPS recordings from Japan to characterize the rupture. The resulting rupture model begins with a steady increase of moment rate for the first 80 s, and a rupture speed of 1.5 km/s. Then the rupture expands southwestward at a speed of about 2.5 km/s. The model's primary slip is concentrated up-dip from the hypocenter, with significant displacement extending to the trench. The seaward location of large slip is consistent with estimates of the tsunami source area from regional and remote tsunami observations. The region with large slip is approximately 150-km wide by 300-km long, which is relatively compact compared with the 200-km wide, 500-km long aftershock region. The model's initial updip rupture expansion and the location of most slip updip of the hypocenter differs from P-wave array back-projections, which map high-frequency radiation along the downdip of the hypocenter, closer to the coast. Key words: Great earthquakes, earthquake rupture processes, broadband seismology

Characteristics of a Crossed-Wire Scatterer Without a Junction Point for an Incident Wave of Circular Polarization

A crossed-wire scatterer has the wires displaced in the backscattering direction, and is able to scatter an incident wave of circular polarization in such a way that the backscattering wave has the same rotational sense as that of the incident wave. The radiation performance of the scatterer is improved by bending the horizontal and the vertical wires. Arrays consisting of crossed-wire scatterers are constructed and the backscattering cross sections (BSCS\u27s) are calculated. It is revealed that the increase in the current amplitude due to the mutual effects among the array elements contributes to enhancement in the BSCS. It is also shown that a maximum value of the BSCS of an array of3 times 3bent crossed-wire scatterers is 1.8 times as large as that of a dihedral corner reflector which has the same aperture area. The BSCS\u27s as a function of the angle of incidence are presented with experimental results at a frequency of 9.375 GHz

PVP2006-ICPVT11-93903 EXPERIMENTS ON THE PLANAR LATERAL VIBRATION OF A VERTICAL FLUID-CONVEYING PIPE WITH AN END MASS

ABSTRACT This paper experimentally examines lateral vibrations of a cantilevered pipe that is hung vertically with an end mass and conveys fluid with a flow velocity that is entirely constant. It is well known from linear stability theory that when the velocity of a fluid exceeds a certain value, a certain characteristic mode of pipe vibration becomes unstable. Moreover, higher modes of pipe vibration become unstable simultaneously with increasing flow velocities. We are interested in the case in which two-frequency oscillation occurs in the pipe involving the above two unstable modes at higher flow velocities. This phenomenon will be called mixed mode flutter. This phenomenon for a cantilevered pipe is essentially different from the cases of a pinedpined or clamped-clamped pipe with two marginal modes. In these cases, only the higher mode of the pipe vibration becomes unstable while the lower mode becomes stable at much higher flow velocities. Experiments were conducted with a silicon rubber pipe conveying water. The planar behaviors of the vertical fluid-conveying pipe with an end mass were observed using an image processing system that is based on the images captured by two CCD cameras. As a result, lower mode flutter, unstable mixed-mode flutter and also higher mode flutter were experimentally confirmed for the cantilevered pipe. Furthermore, the above phenomena are discussed using the basic equation of nonlinear planar lateral vibration of a vertical fluid-conveying pipe with an end mass from the viewpoint of nonlinear dynamics

Shortening Ratios of Modified Dipole Antennas

Two types of modified dipole antennas, zigzag and meander-line types, are analyzed and the shortening ratios are calculated. A zigzag dipole antenna with a wire length of 0.58 wavelengths has a shortening ratio of 24 percent with a resonant resistance of46 Omega. A meander-line dipole antenna with a wire length of 0.70 wavelengths has a shortening ratio of 30 percent with a resonant resistance of43 Omega. It is found that the radiation patterns of these two types of antennas are similar to the radiation pattern of a conventional half-wave linear dipole antenna