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[en] KAERI is constructing the PSA Integrated database for UCN 3, 4 nuclear power plant. PSA Integrated DB includes PSA Model Database and PSA Information Database. PSA model DB consists of PSA models and data which are used for PSA quantification. This paper describes the development of PSA automatic quantification system that calculates the core damage frequency according to the initiating event scenario. We describe the design of PSA model DB schema, the design and implementation of automatic quantification for PSA and the study for the storing of results of that quantification. Recently, we have developed the prototype of PSA automatic quantification system and we are developing more flexible system that applies the various user input and scenario changes
[en] Cigarette smoking and nicotine have complex effects on human physiology and behavior, including some effects similar to those elicited by inhibition of aromatase, the last enzyme in estrogen biosynthesis. We report the first in vivo primate study to determine whether there is a direct effect of nicotine administration on brain aromatase. Brain aromatase availability was examined with positron emission tomography and the selective aromatase inhibitor (11C)vorozole in six baboons before and after exposure to IV nicotine at .015 and .03 mg/kg. Nicotine administration produced significant, dose-dependent reductions in (11C)vorozole binding. The amygdala and preoptic area showed the largest reductions. Plasma levels of nicotine and its major metabolite cotinine were similar to those found in cigarette smokers. Nicotine interacts in vivo with primate brain aromatase in regions involved in mood, aggression, and sexual behavior.
[en] Development of 1-dimensional gold and silver nanomaterials are synthesized through proton beam irradiation. Synthesis of gold nanomaterials via proton beam irradiation Gold nanocrystals were formed by proton beam irradiation (24 MeV, 1.09 Gy/s). Spherical gold nanoparticles in the range of 27 nm were prepared when the HAuCl4-containing mixture was irradiated under proton beam with an average current of 10 nA for 30 min. When the reaction mixture was irradiated for 60 min, Au nanomaterials including gold nanoparticles and nanorods were synthesized. The aspect ratio of the resulting Au nanorods was in the range of 3. Synthesis of silver nanomaterials via proton beam irradiation Ag nanocrystals were formed by proton beam irradiation (24 MeV, 1.09 Gy/s). Spherical silver nanoparticles were prepared when the AgNO3-containing solution mixture was irradiated under proton beam. It was observed that the average diameter of the silver nanoparticles was increased from 5 nm to 30 nm, as the beam irradiation was increased. It was also found as the concentration of the silver ion was increased, the diameter of the synthesized Ag nanoparticles was gradually increased
[en] In the event of a near-shore oil spill, the use of a web-based Geographic Information System (GIS) can greatly improve emergency response management and oil recovery operations by providing real-time information support. This paper presented a Web-GIS that is used in combination with an oil spill simulation model. The structure and content of the system was defined after the Nakhodka vessel spilled oil in the Sea of Japan in January 1997, leaving serious environmental damage to the coastal area of the Ishikawa prefecture. The Web-GIS provides a wide range of environmental and oil spill related information, presented in a geographical form. The system also consolidates spill and environmental damage related information from different sources and provides links to the specialized environmental and socio-economical information of other GIS databases. The oil spill modeling subsystem is part of an application for protection planning and oil recovery operations. With this system, oil-drift simulation begins at the onset of any oil spill and then remote sensing data are used to estimate the position and state of the spilled oil. The spill information is then assimilated into the spill model and the observed simulated results are uploaded to the Web page for public information. The applicability of the Web-GIS is extended by support for information gathering from the public and the responsible agencies. The relative simplicity of the system interface is an added advantage. 9 refs., 4 figs
[en] This work is concerned with the application of an electrochemical noise (EN) monitoring technique to analyze the initiation and propagation of Pb-assisted stress corrosion cracking (SCC) of Ni-based alloys in a simulated environment of a steam generator (SG) sludge pile at high temperatures. The EN was measured on C-ring specimens in the highly caustic solution containing oxidizing impurities such as PbO and/or CuO in two different ways: in a potentiostatic controlled current noise (PCCN) mode, the electrochemical current noise (ECN) was measured from the stressed C-ring specimen by applying an anodic potential. In an uncorrelated three electrode current and potential noise (UCPN) mode, the electrochemical potential noise (EPN) and the ECN were measured simultaneously from the stressed C-ring specimen. Typical increase of ECN and decrease of EPN were frequently recorded from the EN measurement in a caustic solution with oxidizing impurities, indicating that there are localized corrosion events occurring. From the EN and the microscopic analyses of Ni-based alloys in the leaded caustic solution environment at high temperature, it is strongly suggested that the repetitive current rises followed by steeper decay with shorter time interval in the time record of the ECN in the PCCN mode are mainly due to the initiation of SCC, whereas the current increases followed by slower decay with longer time interval are attributable to its propagation. From the spectral analysis of the ECN in PCCN mode, the PSD increased more remarkably at low frequency limit for the propagation of SCC as compared to that for the initiation of SCC. Similar trends were observed in both ECN and EPN measured in the UCPN mode in the caustic solution environments with various oxidizing impurities. In addition, from the stochastic analysis of the EPN obtained in the UCPN mode, it was found the shape parameter of the Weibull distribution of the mean time-to-failure for the initiation of SCC is clearly distinguishable from that parameter for the propagation of SCC as well as for the general corrosion. (author)
[en] Gold nanocrystals were formed by proton beam irradiation. Spherical gold nanoparticles in the range of 27nm were prepared when the HAuCl4-containing mixture was irradiated under proton beam with an average current of 10nA for 30 min. When the reaction mixture was irradiated for 60 min, Au nanomaterials including gold nanoparticles and nanorods were synthesized. Ag nanocrystals were formed by proton beam irradiation. Spherical silver nanoparticles were prepared when the AgNO3-containing solution mixture was irradiated under proton beam. It was observed that the average diameter of the silver nanoparticle was increased from 5 nm to 30 nm, as the beam irradiation was increased. It was also found as the concentration of the silver ion was increased, the diameter of the synthesized Ag nanoparticles was gradually increased
[en] Radiographic findings of thirty eight cases of renal tuberculosis treated at this hospital during last 4 years were analysed with following results. The cases examined were 24 male and 14 female patients. Age distribution was broad and evenly distributed ranging from 2nd decades to 5th decades. Main symptoms complained were urinary frequency, hematuria, dysuria and flank pain. Findings of physical examination revealed tenderness of costovertebral angle, palpable mass on flank area and epididymal indutration. The simple chest films showed pulmonary tuberculosis in 22 cases including 6 cases of active military type. Thirty one cases showed increased ESR, 8 cases showed AFB positive in urine and 12 cases showed bilateral renal tuberculosis. Through urographic findings nonvisualization, cyceopelviectasis, motheaten appearance of minor calyx, contracted bladder, delayed visualization, ureteral stricture and beading were observed in order of frequency. Five cases with miliary tuberculosis showed advanced renal lesion on urogram
[en] A complete stand-alone state-of-the-art model has been developed of the interaction between corium debris in the lower plenum and the RPV walls and internal structures, including the vessel failure mechanisms. This new model has been formulated as a set of consistent computer modules which could be linked with other existing models and/or computer codes. The combined lower head and lower plenum modules were parametrically tested and applied to predict the consequences of a hypothetical station blackout in a Swedish BWR. (author)
[en] Proton irradiations in the cells were significantly decreased cell viability but increased the QR activity in a dose-dependent manner. Cell viability was 92.3%, 88.4%, 81.8%, 72.4%, 68.9% at doses of 0.5, 2, 8, 16, and 32 Gy, respectively. At doses of 2, 8, 16, and 32 Gy, QR activity was increased 1.27-, 1.31-, 1.45- and 2.08-fold. However, negligible GST activity in the cells was detected and the activity was not changed by proton irradiation. Proton irradiation also increased GSH contents by 1.18- and 1.21-fold at doses of 0.5 and 2 Gy. In contrast, the ODC activity, a key enzyme in polyamine biosynthesis and tumor promotion, was decreased in a dose-dependent manner. We also investigated anti-metastatic effects of proton beam irradiation in breast cancer cells. Invasion and wound healing assay showed that metastatic activities in breast cancer cells were significantly decreased in a dose-dependent manner by proton beam irradiation. In zymography of MMP-9, the activity was slightly diminished. These results suggest that breast cancer chemopreventive potential was increased with proton irradiation by increasing the QR activity and the GSH levels and by inhibiting the ODC activity.
[en] A test facility has been constructed to evaluate high-current positive ion beams from small gaseous samples for AMS applications. The major components include a compact permanent magnet microwave ion source built at the AECL Chalk River Laboratory and now on loan from the University of Toronto, and a double-focusing spectrometer magnet on loan from Argonne National Laboratory. Samples are introduced by means of a silica capillary injection system. Loop injection into a carrier gas provides a stable feed for the microwave driven plasma. The magnetic analysis system is utilized to isolate carbon ions derived from CO2 samples from other products of the plasma discharge, including argon ions of the carrier gas. With a smaller discharge chamber, we hope to exceed a conversion efficiency of 14% for carbon ions produced per atom, which we reported at AMS-7. The next step will be to construct an efficient charge-exchange cell, to produce negative ions for injection into the WHOI recombinator injector