A Silicon-Emulsion Shower Counter for Cosmic Ray High Energy Electron Observation

An instrument consisting of a combination of position sensitive silicon detectors, nuclear emulsion plates and lead plates is proposed for measurement of the energy of primary cosmic ray electrons with the energy of lower than 30 GeV. As position sensitive detector, two dimensional Si(Li) circular detectors with sensitive area of 38.5 cm2 have been fabricated and build-up curves (transition curves) of deposited energy in the detector versus thickness of lead plate for high energy electron beams are presented as fundamental data for design of such an instrument.     

A low damage, low contaminant plasma processing system utilizingenergy clean technology

A plasma processing system for ULSI device manufacturing using energy clean technology is proposed that is capable of subtle control of ion impact energy under very low pressure and magnetron enhancement. Careful and extensive probe measurements were carried out to determine the effects of magnetic field, plasma excitation frequency, DC-biasing of plasma confining cylinder (shield), DC-biasing of electrodes and secondary RF excitation on spatial distribution of potential. It was found that the substrate DC potential can be effectively controlled by DC-biasing or RF-biasing using an external DC power source or a secondary RF excitation, respectively. As a consequence, the wafer-surface damage induced by the high energy ions can be minimized by directly controlling the potential difference between plasma and substrate. The study also found that DC-biasing of the shield is very effective in minimizing the chamber material contamination, i.e., the contamination levels of both iron and copper atoms measured by total reflection X-ray fluorescence spectroscopy     

Low-level cadmium exposure in Toyama City and its surroundings in Toyama prefecture, Japan, with references to possible contribution of shellfish intake to increase urinary cadmium levels

OBJECTIVES: This study was initiated to examine if exposure to cadmium (Cd) was high also outside of the previously identified Itai-itai disease endemic region in the Jinzu River basin in Toyama prefecture in Japan. METHODS: Morning spot urine samples were collected in June-August 2004 from 651 adult women (including 535 never-smokers) in various regions in Toyama prefecture, and subjected to urinalyses for cadmium (Cd), alpha1-microglobulin (alpha1-MG), beta2-microglobulin (beta2-MG), N-acetyl-beta-D-glucosaminidase (NAG), specific gravity (SG or sg) and creatinine (CR or cr). Three months later, the second urine samples were collected from those with elevated Cd in urine (e.g., > or =4 microg/g cr), together with answers to questionnaires on shellfish consumption. RESULTS: The geometric mean (GM) Cd, alpha1-MG, beta2-MG and NAG (after correction for CR) for the total participants were 2.0 microg/g cr, 2.4 mg/g cr, 104 microg/g cr and 2.8 units/g cr, respectively; further analysis with never-smoking cases only did not induce significant changes in these parameters. Analyses of the second urine samples from the high Cd subjects showed that there was substantial decrease (to about a half) in Cd in the 3-month period, and that the decrease was accompanied by reduction in alpha1-MG and NAG (beta2-MG did not show elevation even in the first samples). The urinalysis results in combination with the results of the questionnaire survey suggest that the high urinary Cd was temporary and might be induced by intake of shellfish that is edible whole. CONCLUSIONS: The overall findings appear to suggest that Cd exposure in Toyama populations (outside of the Itai-itai disease endemic region) was at the levels commonly observed on the coast of the Sea of Japan, and that the Cd level in urine might be modified by the intake of some types of seafood. Further studies are necessary to elucidate the relation of urinary Cd with seafood intake.     

Lipase-Catalyzed Esterification of Triterpene Alcohols and Phytosterols with Oleic Acid

Oleic acid esters of phytosterols (PSs) and triterpene alcohols (TAs), derived from rice bran, were synthesized using lipases under mild conditions. Some lipases, especially from Candida rugosa, type VII, showed very high substrate specificity towards both PSs and TAs, when a mixture of PS and TA (PS/TA mixture) was used as the substrate source. The maximum yield of PS esters was ca. 80 % in each case; however, the maximum yield of TA esters was much lower when the reaction was continued for 7 days. Due to the difficulty in purifying the esters obtained when the PS/TA mixture was used as source of substrate, free PSs and TAs were separated from the PS/TA mixture by silica-gel and reverse-phase chromatography prior to esterification. The pure PSs or TAs were esterified with oleic acid to obtain the corresponding esters with high purity. Differential scanning calorimetric analysis of the resulting esters revealed that their melting points ranged from 7.0 to 42 °C. These values were at least 100 °C lower than those of the free PSs and TAs.     

Conceptual considerations on PV systems composed of AC modules

AC module technology has become popular and a number of AC module types are commercially available. Although their specifications are clear, it seems that their technological meaning has not yet been well developed. Therefore, the authors tried to create the total concepts of PV systems composed of AC modules. They are abbreviated AC module-composed PV system or ACM-PV. In the paper, the possible structural configurations of simple AC modules and battery integrated ones are classified in principle. System categories are also classified to show their total concept. Necessary electrical terminals and interfaces, voltage matching method between inverter and PV part, and AC module testing methods are also discussed.     

Framework of a flexible computer communication network

With the increasing speed of computers and communication links, and the successful convergence of both fields, computers connected by high speed links now represent an enormously large distributed computing system. At the same time, communication between man and machine is also becoming more diverse and personalized. Networking issues such as evolution of user services, seamless communication between hosts, failure recovery and integration of new technologies arise daily. Problem-specific approaches and corresponding solutions are available at considerable cost. However, a common requirement is adaptability of the computer network to a variety of changes. In this paper, we propose Flexible Computer Communication Networks (FN) as a uniform solution to most of these networking problems. The framework of Flexible Networks can be considered as an intelligent shell enclosing existing networking architectures. An agent-oriented implementation of a flexible network is outlined. The conversion of existing networks to flexible networks is shown to be incremental, and therefore practicable.     

Role of Fas-Fas ligand interactions in the immunorejection of allogeneic mouse corneal transplants

BACKGROUND: The expression of Fas ligand (FasL) in the eye has been proposed to be an important component of ocular immune privilege. Since the unusually favorable outcome of corneal transplantation is thought to result from the immune privilege of the eye, examination of the function of FasL on corneal allografts would be a test of that hypothesis. METHODS: To investigate the role of Fas-FasL interaction in corneal allografts, orthotopic corneal transplantation was performed using C57BL/6 (B6, FasL+) and B6-gld (FasL-) mice as cornea donors and BALB/c mice as recipients. The rejection rate of B6-gld grafts (FasL- group) was compared with that of normal B6 control corneas. RESULTS: The rejection rate at the final observation (8 weeks) in the FasL- group (89%) was significantly higher than in the FasL+ control group (47%). FasL expression was found on the corneal endothelium by staining with anti-FasL monoclonal antibodies. The TdT-mediated dUTP nick-end labeling assay revealed that apoptotic cells were attached to the endothelium in the control group but not in the FasL- groups. CONCLUSIONS: Apoptosis of infiltrating cells on the corneal endothelium resulting from Fas-FasL interaction plays an important role in the high success rate of corneal transplantation.     

Phosphate coupling agents for calcium carbonate filler

Phosphate coupling agents, i.e., alkyl dihydrogenphosphates containing functional groups such as olefinic, chloro, methacryloxy, and mercapto, were synthesized and allowed to react with calcium carbonate filler suspended in an aqueous medium. The modification provided the filler with good dispersibility in mineral oil. Physical properties of the vulcanized rubbers loaded with the modified fillers were found to be influenced by the functional group introduced. For example, in peroxidecured ethylene–propylene–diene rubber (EPDM), the methacryloxy group was most effective, and the mercapto group significantly enhanced the physical properties of sulfur-cured styrene–butadiene rubber (SBR), while a saturated aliphatic phosphate was ineffective in both curing systems. Deposition of the coupling agent as calcium salt onto calcium carbonate surface was observed by scanning electron micrography. The novel approach for the surface modification of calcium carbonate filler is descussed in relation to the reinforcing effects on rubbery materials.     

Effects of dietary supplementation of ferulic acid and gamma-oryzanol on integument color and suppression of oxidative stress in cultured red sea bream, Pagrus major

The effects of ferulic acid (FA) and gamma-oryzanol (OZ) supplementation on cultured red sea bream were examined. Commercial brown fish meal diets supplemented with FA (0.01-0.5%) or OZ (0.05-0.5%) were given to zero-year, cultured red sea bream for 98 days. After the experiment, the brightness of the integument color ("L" value) of FA- and OZ-administrated fish was higher than that of control fish. Furthermore, 2-Thiobarbituric acid reactive substances (TBARS) in the liver of FA- and OZ-administrated fish was lower than in control fish. These results indicate that FA and OZ suppressed not only dark-color pigmentation but also oxidative stress in cultured red sea bream.     

基于非线性破坏包络线的三维边坡稳定性分析

The effects of nonlinearity of strength envelopes on 3D slope stability analysis are investigated.A power relation for the nonlinear envelope is employed to derive the 3D factor of safety equations of an extended Spencer method hich satisfies boty force equilibrium and moment equilibrium.Then,a search procedure is presented based on dynamic programming to determine the 3D critical slip surface for a general slope,Linear and nonlinear strength envelopes used for slope stability computations are obtained by fitting curves to the 103 strength data of consolidated-undrained(CU)triaxial compression tests for compacted Israeli clay.Results of a typical 3D problem show that a linear approximation of the nonlinear strength envelope may lead to a significant overestimation of calculated safety factors.