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A patient with a history of hepatocellular carcinoma was found to have multiple pulmonary metastases. Staged treatments were combined into a single operation session in the hybrid theater, encompassing bronchoscopic microwave ablation of central right upper lobe lesions and uniportal surgical wedge resections of peripheral right middle lobe lesions. All lung metastases were successfully treated with adequate margin clearance. Microwave ablation under the guidance of electromagnetic navigation bronchoscopy in the hybrid theater is a novel contribution to the multimodal operative management of multiple pulmonary neoplasms. It is a unique choice for patients with multilobar, subcentimeter metastases, and with concerns about lung function preservation.

We describe a case of total arch replacement with frozen elephant trunk for chronic type B aortic dissecting aneurysm, which resulted in inadvertent landing of the frozen elephant trunk into the false lumen. A radiofrequency puncture system-assisted controlled endovascular fenestration of the dissection flap was performed at the upper abdominal aorta and subsequent thoracic endovascular stenting, successfully redirecting the blood flow from the false to the true lumen. Our case illustrated a possible way to seal distal reentry in chronic type B aortic dissection.

The dissociative photoionization of vinyl bromide (C2H3Br) has been investigated by photoionization mass spectrometry (PIMS) and time-of-flight threshold photoelectron-photoion coincidence (TOF-TPEPICO) spectrometry using synchrotron radiation. The photoionization efficiency curves of the three most abundant ions, i.e. C2H3Br+, C 2 H 3 + and C 2 H 2 + , are measured and analyzed in detail. A C 2 H 3 + / Br - photoion-pair formation process has been detected for the first time. Some arguments are provided in favor of the electronic excitation of the C 2 H 3 + fragment and of the isomerization of the C 2 H 2 + ions. The breakdown diagram for these ions in the 9.8–21 eV photon energy range, derived from TOF-TPEPICO mass spectra, is discussed. The involvement of the successive C2H3Br+ ionic states and the role of autoionization of C2H3Br Rydberg states are emphasized. For the two minor HBr+ and Br+ fragment ions only the breakdown diagrams are measured and appearance energies are derived.

The triaxial superdeformed rotational bands in the odd–odd Lu 160 ∼ 168 isotopes are investigated by performing the configuration dependent three-dimensional total routhian surface calculations. About fifty low lying triaxial superdeformed bands have been found for these odd–odd nuclei within the excitation energy of 3 MeV above the normal deformed yrast bands. The calculated equilibrium elongation, triaxial and hexadecapole deformations for these triaxial superdeformed bands are close to the values of e 2 ∼ 0.4 , γ ∼ 20 ° and e 4 ∼ 0.03 , respectively. The configurations of calculated triaxial superdeformed bands have been assigned based on the total routhian surface calculations and the analysis of quasiparticle routhians in the rotating frame. The observed yrast triaxial superdeformed band of 164Lu, where the linking transitions between superdeformed and normal deformed states are measured, have been reproduced by the present calculation in the relative energy to the normal deformed band. We show that the stability of superdeformed triaxial shapes in the odd–odd Lu isotopes is similar to that presented in odd–even Lu nuclei, and thus the wobbling excitations could be expected to occur in odd–odd Lu isotopes. The deformation driving effect of the proton high-j low-K orbit play an important role in the formation of the triaxial superdeformed states in both odd–odd and odd–even Lu isotopes, while the shell effect is a fundamental factor for the triaxial superdeformed shapes. The shell gaps and the positions of the deformation driving intruder orbits which are responsible for the triaxial superdeformed minima have been localized, particularly, the neutron N = 94 gap and the position of the proton [ 660 ] 1 / 2 orbit in the deformed single particle diagram provide the basis for a microscopic understanding of the observed triaxial superdeformed bands in the mass region.

A single crystal of Ag–36.7 at.% Al aged within the hexagonal close-packed (h.c.p.) δ-phase region of the phase diagram at 366 K was investigated by diffuse X-ray scattering. Diffuse scattering maxima were found at 2 k F positions where k F is the Fermi wave number along 〈1 1 0] . The contributions from short-range order scattering, linear size-effect scattering, Huang scattering and thermal diffuse scattering were separated by least-squares fitting of the corresponding Fourier series. In crystals modeled on the basis of 40 Warren–Cowley short-range order parameters, nearest-neighbor configurations are found which are characteristic of a superstructure introduced by Neumann as a possible ground-state structure of h.c.p. Ag–Al. Effective pair interaction parameters of the first 12 shells determined by the inverse Monte Carlo method were used in Monte Carlo simulations. For the Neumann structure, an order–disorder transition temperature of ∼100 K is estimated.

X-ray absorption near edge structure (XANES), utilizing both electron yield and X-ray fluorescence detectors, and X-ray photoelectron spectroscopy (XPS) were used to follow chloride uptake by oxide-covered aluminum in 0.1 M NaCl solutions. The aluminum samples were polarized at selected potentials below (less positive than) the pitting potential. The electron yield XANES and XPS showed multiple peaks. The XPS chloride spectra showed two distinct sets of doublets. One doublet is related to chloride on the surface and the second is related to chloride incorporated in the oxide film. The XANES results also showed two peaks which are attributed to chloride on the surface and in the bulk of the oxide.

In a recent publication, Kuhlmann et al. (Acta mater., 1997, 45, 3319) claimed Cu–10 at.% Au to be long-range ordered at temperatures above 473 K and as high as 723 K. This is in contrast to the generally accepted phase diagram where this region is attributed to the range of solid solutions. To clarify this problem, a three-dimensional diffuse X-ray scattering experiment was performed at room temperature on a Cu–10 at.% Au single crystal aged at 573 K. The Warren–Cowley short-range order parameters derived from this experiment show conclusively that only short-range order is present. Effective pair interaction parameters determined by the inverse Monte-Carlo method are somewhat different from those obtained for Cu–25 at.% Au in the short-range ordered state.

Tube spinnability is defined as the maximum thickness reduction before either fracture or buckling under the given roller geometry, feed rate, and the speed of the mandrel during the tube spinning of a metal. There are two ways employed to experimentally determine the tube spinnability of the full-annealed and solution-treated AA 2024 and 7075 aluminum alloys. One is to reduce the thickness stepwise to the final thickness without failure the tube. The other is the one-path spinning with continuous reduction in wall thickness of preform from initial to the final thickness without buckling to determine the achieved maximum reduction. Using continuous reduction test, the determined macro-spinnability of full-annealed AA 2024 aluminum alloys is 75% and 7075 aluminum is 74%. Whereas, when examined by scanning electron microscope, the deformation tongue is visible on the outer surface as the thickness reduction higher above 50% for both full annealed 2024 and 7075 aluminum alloys. However, for both solution-treated 2024 and 7075 tubes, the spinnability is lower than that of full-annealed conditions. The discrepancy between the reduction test and microscopic spinnability will be discussed in terms of the microstructure and the mechanical properties.

Carriers are injected into the delay path of the BARITT structure with zero drift velocity, hence, diffusion can not be neglected in the small signal analysis. The inclusion of a diffusion region adjacent to the injection plane produces a more physically reasonable approach to the small signal analysis. This analysis is accomplished through a regional approximation. The three regions are the diffusion region (where diffusion dominates the conduction process) a low field region (where drift dominates but the carrier velocity has not reached the saturation velocity) and a high field region (where the carriers drift with a saturated velocity). The inclusion of the diffusion region removes the zero-velocity singularity which results in the conventional analysis and accounts for an appreciable delay which has been previously neglected. The device characteristics are optimized for various device parameters. The optimized device length and most probable value of the negative resistance are given, and a qualitative discussion of the physical origin of the behavior of the device characteristics is given.

Lung collagen was studied in hamsters which had been intratracheally instilled with elastase. Total and insoluble collagens in lungs among the elastase-instilled were higher than those of the age-matched controls and continued to be elevated even 4 months after the elastase-instillation. A transient increase in salt-soluble collagen during the period 6 to 20 days after the elastase-instillation was also found among the experimentals. Studies of incorporation of l -[ 14 C]proline into lung collagen showed higher specific radioactivities in both hydroxyproline and collagen fractions as well as a many-fold increase in total radioactivities in collagen fractions of lungs among the elastase-instilled hamsters. The results indicated that collagen metabolism in hamster lungs was activated after the elastase-injury which led to an increase of collagen in lung.