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A novel approach to three-dimensional morphometry of the thoracic aorta was developed by applying centerline analysis based on least-squares plane fitting, and a preliminary study was conducted using computed tomography imaging data.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jtcvs.2006.11.042 Byline: Mitsuru Asano, Ohtake Hiroshi, Yuji Hanafusa, Hiroshi Kazuma, Masahiro Tanji Author Affiliation: Department of Cardiovascular Surgery, Ohta General Hospital Foundation, Ohta Nishinouchi Hospital, Koriyama City, Fukushima, Japan. Article History: Received 14 November 2006; Accepted 20 November 2006

Total arch replacement (TAR) for aneurysm of the aortic arch through the midsternotomy has several advantages over left thoracotomy. The purpose of this study was to identify the factors that might have an effect on the distal anastomosis through midsternotomy. From October 1999 to August 2005, 125 patients underwent TAR for aneurysm of the aortic arch through midsternotomy. Ninety-four patients with antegrade cerebral perfusion were selected. Distal anastomosis was performed under circulatory arrest (CA) of the lower body. Preoperatively, the diameter of aneurysm, the depth of distal end of aneurysm from anterior skin surface and the anteroposterior diameter of body trunk were measured. Postoperatively, the distance from the carina to the distal anastomosis was measured. There were six early deaths (6.4%). Duration of CA was 37+/-7.6 min. Diameter of the aneurysm was 60.6+/-13.2 mm and the depth of the distal end of aneurysm was 139+/-20.6 mm. There was no correlation between CA time and these factors. The anteroposterior diameter of body trunk was 200+/-18.0 mm and has a correlation with CA time. The depth of distal end of aneurysm from anterior skin surface was the only factor that affected duration for distal anastomosis.

A mass-spectrometric Knudsen-effusion method has been used for the study of the vaporization behaviour of Ba3B2O6(s) in the temperature range 1434 to 1630 K. Vapour species of Ba(g), BaBO2(g), BO(g), B2O2(g), and B2O3(g) have been found. From their partial pressures, the molar enthalpies of formation and dissociation for BaBO2(g) have been determined to be ΔfHmo(BaBO2, g, 298.15 K) = −(633 ± 21) kJ · mol−1and {ΔfHmo(Ba, g, 298.15 K) + ΔfHmo(BO2, g, 298.15 K) − ΔfHmo(BaBO2, g, 298.15 K)} = (524 ± 18) kJ · mol−1, and the molar enthalpies of formation for Ba3B2O6(s) from the elements and from the constituent oxides to be ΔfHmo(Ba3B2O6, s, 298.15 K) = −(3469 ± 50) kJ · mol−1and {ΔfHmo(Ba3B2O6, s, 298.15 K) − 3ΔfHmo(BaO, s, 298.15 K) − ΔfHmo(B2O3, s, 298.15 K)} = −(552 ± 50) kJ · mol−1, respectively.

A mass-spectrometric Knudsen effusion method has been used for thermochemical study of the vaporization of alkali borosilicate glasses in the R2O-Cs2O-B2O3-SiO2 system, where R = Li, Na, K and Rb. Vapours of RBO2(g), CsBO2(g), R2(BO2)2(g) and RCs(BO2)2(g) have been identified. Over the glasses in which the molar ratio of (R2O + Cs2O)/B2O3 is slightly larger than unity, vapours of R(g), except for Li(g), have been further observed in the initial stage of heating; over the glass containing lithium, however, the vaporization of Cs(g) has been found. Neither R(g) nor Cs(g) has been identified over the glasses in which the molar ratio is equal to unity. Partial pressures of CsBO2(g) over the glasses containing lithium and sodium are lower than those with potassium and rubidium, indicating that chemical activities of the CsBO2 pseudo-component in the glasses with lithium and sodium are small. Enthalpies of formation as well as dissociation energies for dimeric vapours of alkali metaborates are not very different from one another, except that the dissociation energies for the dimeric vapours containing lithium are larger than for those containing the other elements.

A quadrupole mass filter was used to determine the partial pressures of Sr(g) and SrO(g) over strontium oxide heated on a platinum-ribbon filament. The ion currents of 88Sr+and 88Sr16O+were measured while the filament temperature was continuously increasing at a heating rate of about 14°C/min; the calculations of the partial pressures were carried out by the integral method for Sr(g) and by the sensitivity-calibration method for SrO(g). The data are represented by:logPSr(g)(atm)=6.633−\frac2.536×104Tin the temperature range of 1643–1851°K, and by:logPSrO(g)(atm)=6.707−\frac2.793×104Tin the 1747–1850°K range. From the values of the partial pressures, the dissociation energy of strontium oxide was determined to be D0°(SrO)=96.2±0.9 kcal/mol by the third-law treatment and D0°(SrO)=102±5 kcal/mol by the second-law treatment.

A 77-year-old, high-risk woman with symptomatic aortic valve stenosis (aortic valve area 0.77 cm2) underwent coronary artery catheterization and right heart catheterization. After catheterization, she suddenly developed hemoptysis, and became hypoxic and hypotonic. She was intubated and the bleeding was stopped using positive end-expiratory pressure. Chest X-ray and computed tomography showed a pulmonary artery (PA) pseudoaneurysm with a maximum diameter of 40 mm at the right middle lobe. Endovascular treatment approaches by coil embolization failed, so surgical resection was indicated. In preparation for the procedure and to reduce perioperative risk, transapical aortic valve implantation was performed. The operation took about 40 minutes and the intraoperative activated clotting time was controlled at 180–200 sec. After successful transapical aortic valve implantation, aneurysmectomy was performed. Intraoperatively, the PA pseudoaneurysm was found to occupy nearly the entire middle lobe. A right middle lobectomy was performed. The operative course was uneventful. Transapical aortic valve implantation may have eliminated the risk of rupture or re-bleeding in such bleeding-prone patient.

To elucidate the mechanism of surface reactions on graphite anodes of lithium-ion secondary batteries, the morphology change of the basal plane of a highly oriented pyrolytic graphite (HOPG) anode in 1 M LiClO4/ethylene carbonate-diethylcarbonate (1:1 by volume) was observed by electrochemical STM. When the sample potential was stepped to 1.1 V vs. Li/Li+, hill-like structures of ca. 10 Å height appeared on the HOPG surface. The hill-like structure in the vicinity of a step was gradually spread out with time, and a part of it exfoliated. It was considered that the intercalation of solvent is responsible for the formation of the hill-like structure and that this process corresponds to the initial stage of solvent decomposition and subsequent film formation processes.

Photoluminescence (PL) dynamics of aluminumquinoline (Alq3; tris(8-hydroxyquinoline) aluminum)-based organic multilayer structures, i.e., Alq3/oxadiazole (t-BuPBD; (2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole), Alq3/cyclopentadiene (PPCP; 1,2,3,4,5-pentaphenyl-1,3-cyclopentadiene), and Alq3/diamine (TPD; N,N'-diphenyl-N,N'-bis-(3-methylphenyl)-[1,1'-biphenyl]-4,4'-diamine), which possess different types of energy lineups (equivalent to types I and II of inorganic semiconductor multilayer structures) of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy levels, were investigated and compared. The fast energy transfer followed by strong PL in Alq3was proved for Alq3/PBD which is of type-I energy lineup, while the tendency of separation of excitons, i.e., electrons and holes generated in the excited molecules, was demonstrated for Alq3/PPCP and Alq3/TPD which are of type II. These results indicate that the energy lineup with respect to HOMO and LUMO energy levels can be a guideline for luminescence dynamics in organic multilayer structures.

Aluminumquinoline-oxadiazole (Alq3-PBD) codeposited layers, where the heterojunction of Alq3and PBD is expected to possess type-I energy lineup, were fabricated by vacuum evaporation, and their optical properties were investigated. The results showed effective energy transfer from PBD to Alq3followed by dominant emission from Alq3, even at the Alq3concentration as low as about 1.5%. By using the Alq3-PBD codeposited layer as the emitting layer of electroluminescence (EL) devices, a successful increase in output power and quantum efficiency was observed compared to conventional EL structures.

Photoluminescence (PL) dynamics of aluminumquinoline/oxadiazole (Alq3/PBD) multilayer structures, which may possess a carrier confinement type-I energy lineup, has been investigated by time-resolved PL spectroscopy with a mode-locked Ti-sapphire laser. The decay time of the emission from PBD in the multilayer structure was as fast as several picoseconds, in contrast to that from a PBD single layer, 1.7 ns, and tended to increase with an increase in PBD thickness. For the emission from Alq3, on the other hand, only a slight increase in the decay time was observed in the multilayer structure compared to a single layer. These results indicate the rapid energy transfer from PBD to Alq3, similar to that in semiconductor quantum well structures with the type-I energy lineup.