Resection of pheochromocytoma under inferior vena caval isolation and extracorporeal charcoal hemoperfusion

Resection of pheochromocytoma is associated with potential risks of hypertensive crises and serious arrhythmias due to massive release of catecholamines from the tumor. We report our surgical experience with complete inferior vena caval isolation and extracorporeal charcoal hemoperfusion (IVCI-CHP), which were performed to prevent systemic exposure to catecholamines during surgical manipulation. The IVCI-CHP significantly reduced the postfilter and systemic catecholamine levels compared with the prefilter levels (P<.01), indicating substantial catecholamine extraction (>90%) by the CHP filter. Reflecting the reduction of systemic exposure to catecholamines during IVCI-CHP, the patient's blood pressures were markedly stable. Our findings suggest that IVCI-CHP may be useful to minimize the risk of hypertensive crises during surgical manipulation of pheochromocytoma, by preventing systemic exposure to high levels of circulatory catecholamines.     

Stability of electrochemomechanical strains in polypyrrole films using ionic liquids

Electrochemomechanical strain (ECMS) of conducting polymers, polypyrrole (PPy) films was studied using several kinds of ionic liquids and the mixed solution with organic solvents from the view points of strain and stability. The PPy films, which were electrodeposited from lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), showed porous morphology. The ECMS in the films operated in ionic liquids was less than 5%, demonstrating a cation movement behavior and stable cycling. By the operation in ionic liquid/propylene carbonate (PC) mixed solution, the ECMS increased up to 24% showing the anion movement, and gradually decreased upon cycling to 16% at 10^th cycle. The strain and stability of the ECMS in mixed electrolyte solution with various ratios of the ionic liquid and PC were studied and discussed in terms of mechanisms of ECMS in mixed solutions.     

HDR image compression and evaluation based on local adaptation using a retinal model

Abstract— The retinal adaptation process helps the human visual system to see high‐dynamic‐range (HDR) scenes in the real world. A simple static local adaptation method for HDR image compression based on a retinal model is presented. The proposed simple model aims at recreating the same sensations of the human visual system between the real‐world scene and the range compressed image on the display device when viewed after the human visual system reaches the steady local adaptation state, respectively. In computing scene local adaptation, the use of a non‐linear edge‐preserving bilateral filter not only presents a better tonal rendition in compressing local contrast and preserving details but also avoids banding artifacts across high‐gradient edges. Our new model relates the display adaptation with the scene adaptation based on the retinal model. In order to verify the effectiveness, a subjective evaluation is made by comparing the real scene and the display image using the paired comparison technique.     

Temperature stable self-biasing bubbles in double layer films

One of the most important problems for a self-biasing bubble (SBB) device is the temperature stability of the SBB diameter. The temperature dependence of the SBB diamater was calculated on the basis of the force stability condition of the SBB and proved to be proportional to the temperature dependence of the characteristic length of the top layer. The proportional coefficient depended on h/l and that was more than -2.7. The smallest value of temperature sensitivity was +0.8%/°C in the system of (YCaEuYb)3GeIG/ (EuEr)3GaIG. No hard bubbles were observed in this self-biasing double layer film and the mobilities of the SBB were similar to those of the usual single layers. And SBB were generated, propagated and detected by means of the usual drive technique (T-Bar permalloy circuits) without any bias field, the operating margins were similar to those of the bubbles in the usual single layer films.     

Stability limit for thermally driven acoustic oscillation

The study of oscillatory instabilities occuring in cryogenic systems has a practical importance in the system development. One form of instability, thermally driven acoustic oscillation, is investigated experimentally using U-shaped tubes. The stability limit of oscillation for helium gas predicted by theory agrees well with our experimental results. The temperature ratio of a warm part to a cold one and the ratio of the inner radius of the tube to the Stokes boundary layer thickness are convenient variables for characterizing thermally driven acoustic oscillation.     

Characterization of the vibrational damping loss factor and viscoelastic properties of ethylene–propylene rubbers reinforced with micro‐scale fillers

The influence of microscale fillers on ethylene–propylene rubbers (EPR) was examined with respect to their vibrational damping capacity and viscoelastic properties. The vibrational damping and dynamic mechanical properties of reinforced EPR were studied in systematic and comparative ways that reinforced the evidence of a direct relation between the vibrational damping loss factor and its mechanical damping loss factor. In this study, the sensitivity of the vibrational damping loss factor of reinforced EPR was quantified with respect to the variation in thickness, filler type, and filler content. Dynamic mechanical relaxation behaviors were also analyzed. The viscoelastic properties in terms of the storage modulus, loss modulus, mechanical damping loss factor, and frequency dependence of molecular relaxation showed interesting results with the filler types and compositions that had good correspondence with the vibrational damping behaviors. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 3058–3066, 2001     

Heat removal characteristics of a concrete cask by a simplified test model

The present study is concerned with the characteristic cooling flow in the annular gap of a concrete cask used to store spent nuclear fuel. The concrete cask is cooled by a natural convection flow of air passing through an internal annular gap between the outside of a canister and the inside of the concrete vessel. The heat transfer coefficient and friction loss coefficient of such a flow could not be fully estimated even if we used existing handbooks, because the airflow has unique features. Simulation experiments using a simplified model for the cooling path have been conducted to estimate the heat transfer coefficient and friction loss coefficient. It was found by this study that the heat transfer coefficient well agreed with the prediction by an empirical formula applied to the free convection, and the friction loss coefficient was 2–2.5 times the value of an isothermal flow.     

Adsorption mechanism of copper and cadmium onto defatted waste biomass

In this study, the amount of copper or cadmium adsorbed using waste biomass (i.e., coffee grounds (CG) and rice bran (RB)) was investigated. The amount of crude protein in defatted CG (D-CG) or RB (D-RB) was greater than that in CG or RB, respectively. The amount of copper or cadmium adsorbed using CG was greater than that using RB. Additionally, the amount of copper or cadmium adsorbed was not affected by the presence of fat in CG. Adsorption data was fitted to the Freundlich equation, and the correlation coefficients were in the range of 0.794-0.991. The main adsorption mechanism was thought to be monolayer adsorption onto the surface of the waste biomass. The adsorption rate data was fitted to the pseudo-second-order model, and the correlation coefficient average was in the range of 0.891-0.945. This result showed that the rate-limiting step may be chemisorption. Moreover, the amount of copper or cadmium desorbed from CG or RB using 0.01 mol/L or 1.00 mol/L HNO(3) was investigated. Desorption with 0.01 mol/L HNO(3) resulted in the recovery of 86-97% of the copper and cadmium, indicating that copper or cadmium that was adsorbed using waste biomass was recoverable.