Analysis for concentric-double inclusions dispersed in continuous media

The behaviors of concentric-double inclusions dispersed in continuous media are investigated theoretically to find some possibilities of improving toughness of composite materials by dispersing double-inc’usions instead of single-inclusions. The general solutions of the Stokes equation, expressed in terms of the spherical harmonics, are used for analyzing the problems that are related to the concentric-double inclusions. From the analysis, it is found that the pressure and stress fields inside and outside the inclusion can be modified by changing the modulus ratios and the thickness of shell layer. Especially, the positions of the minimum pressure points and the maximum stress points turn out to be controllable with some degree of freedom.     

Multiple gene duplication and expression of mouse bcl-2-related genes, A1

Atrial reentrant tachycardia (ART) was ablated in an anatomically guided approach. Five patients with ART underwent 2 linear incisions without careful pace or activation mapping. One line was from an atrial activation site earlier than P wave onset to the nearest fixed anatomic conduction barrier, i.e., the inferior vena cava or coronary sinus ostium. The other line was made just above or closely crossed the first line vertically. Mean application time was 29 +/- 19 minutes, and the application energy was 14,001 +/- 12,322 joules. Mean follow-up after ablation was 15 +/- 10 months. Three patients underwent electrophysiologic study three months after and sustained ART was not induced. All patients were free of sustained tachycardia events without antiarrhythmic drugs during the postoperative clinical course. Although anatomically guided ablation for ART requires much time and energy, it is easily and effectively done without careful activation or pace mapping, and is indicated if ablation using activation mapping or entrainment technique fails to cure the ART.     

Pathological changes according to the severity of asthma

BACKGROUND: There have been many studies concerning pathological changes in bronchial mucosa from asthmatics; however, few studies has been carried out to evaluate pathological changes according to the severity of asthma. OBJECTIVE: This study was designed to evaluate the cellular components in bronchoalveolar lavage fluid (BALF) and histological abnormalities in asthmatics according to the severity of asthma. METHODS: Bronchoalveolar lavages, bronchoscopic biopsies and ultrastructural examinations were performed in 13 asthmatics and 11 (BAL) or four (biopsies) non-asthmatic controls. The proportions of epithelial cells and correlations with PC20Meth which reflects bronchial hyperresponsiveness. Light microscopic examination revealed loss of epithelium, inflammatory cell infiltrations and thickening of the basement membrane which also showed significant correlation with PC20Meth. Hypertrophy of airway smooth muscles and hyperplasia of mucous glands were prominent in asthmatics but there was no difference according to the severity of asthma. Ultrastructural examination revealed that basement membrane thickening on light microscopic examination is due to the increased subepithelial collagen deposition with normal thickness of basal lamina. CONCLUSION: These data suggest that loss of epithelial cells, infiltration of inflammatory cells, especially eosinophils, and increased deposition of subepithelial collagen play major roles in determining the severity of asthma and non-specific bronchial hyperresponsiveness.     

A new triple stain for Helicobacter pylori suitable for the autostainer: carbol fuchsin/Alcian blue/hematoxylin-eosin

OBJECTIVE: To develop an inexpensive stain to simultaneously visualize gastric morphology and Helicobacter pylori. METHODS: Gastric biopsies were stained with Genta stain using manual methods, and with carbol fuchsin/Alcian blue/hematoxylin-eosin using an automatic slide stainer (Sakura DRS-601). Slides were then coded and interpreted by 2 pathologists. Helicobacter pylori was scored using a visual scale (0 [none] to 5 [maximum]). RESULTS: One hundred slides were scored; H pylori was present in 64%. Carbol fuchsin/Alcian blue/hematoxylin-eosin stain gave excellent demonstration of gastric morphology. All positive cases (score > or =2) were correctly interpreted. Thirty-six slides had a score of 1 (< or =2 bacteria per entire slide). Of these, 10 were scored negative by Genta stain and 12 were scored negative by the carbol fuchsin/Alcian blue/hematoxylin-eosin stain (P = not significant). Hematoxylin-eosin was significantly less accurate than either of the other 2 stains (P < .02). CONCLUSION: The carbol fuchsin/Alcian blue/hematoxylin-eosin (El-Zimaity) stain is an economical stain suitable for simultaneous visualization of H pylori infection and gastric morphology.     

Ruthenium-catalyzed cross-coupling reactions between ketones and primary amines

Ketones react with primary amines in dioxane at 180 °C in the presence of a catalytic amount of a ruthenium catalyst to give the corresponding α-alkylated ketones in moderate to good yields. With alkyl(methyl) ketones, the alkylation takes place exclusively at less-hindered methyl position over α-methylene.     

Evaluation of performance and service life of low pressure lPG regulators for home use

This paper presents the evaluation of LPG (Liquefied petroleum gas) regulators for home use. For the evaluation, several properties of the regulators were experimentally analyzed, such as the operation of safety device, the adjusting and lock-up pressure, the adjusting spring and the diaphragm, with respect to the used time of the regulators. Experimental results showed that the initial operation performances of regulators were degraded with increase of the service time and also showed that the degradation of the performance and material property could become serious after about six-year-use of the regulators.     

Gallium-nitride microwave Doherty power amplifier with 40 W PEP and 68% PAE

A 40 W gallium-nitride microwave Doherty power amplifier for WCDMA repeater applications is presented. The main amplifier and peaking amplifier are implemented using two 20 W PEP GaN HEMTs. Performance is evaluated for broadband gain, power efficiency and adjacent-channel-power-ratio (ACPR). Experimental results of the GaN Doherty amplifier yielded a power gain of over 11 dB from 1.8 to 2.5 GHz, 68% power added efficiency at 40 W peak power. Good linearity performance of -48 dBc ACPR is obtained at a peak-to-average ratio of 9.8 dB.     

Axisymmetric modal analysis of liquid‐storage tanks considering compressibility effects

In this paper, we address analytical and numerical studies on the free vibration of fluid–structure interaction problems considering the fluid compressibility. According to the separation of variables together with the boundary condition enforcement, we first derive a compressible‐fluid velocity potential function. Next, we split the structure region into the wet and dry parts, for which we apply the Novozhilov thin shell theory. Combining two dynamic displacement fields, for two split structure parts, using the displacement compatibility conditions, we finally obtain a simultaneous equation system for computing natural frequencies and modes. According to the derived analytical formulae, we compute natural frequencies and modes, stress resultants, together with the comparison with the FEM analysis and the incompressible case. Numerical results show, compared to the incompressible case, that the compressible case produces lower natural frequencies and, furthermore, the relative difference is influenced by the slenderness of tanks and the relative liquid fill height. Copyright © 2002 John Wiley & Sons, Ltd.