• Nuclear Engineering and Technology
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• v.27 no.1
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• pp.53-66
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• 1995

Since the current licensed system codes for Non-LOCA safety analysis are applicable only for a specific type PWR, it is necessary to develope a new system analysis code applicable for all apes of PWRs. As a R&D program, KAERI is developing TASS code as an interactive and faster-than-real-time code for the NSSS transient simulation of both CE and Westinghouse plane. It is flexible tool for PWR analysis which gives the user complete control over the simulation through convenient input and output options. In this paper the code applicability to Westinghouse ape plants was verified by comparing the TASS prediction to plant data of loss of AC power and loss of load transients, and comparing to the prediction of RELAP5/MOD3 for feedline break, locked rotor, steam generator tube rupture and steam line break accidents.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.475-481
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• 1996

A simple, fast, inexpensive method hal been developed to extract organochlorine pesticide spiked in fish tissues by supercritical carbon dioxide. Following static supercritical fluid extraction (SFE), pesticides are collected by rapidly depressurizing the carbon dioxide effluent through a 0.79 mm i.d. metering valve into a capped screw-top tube. Percent recovers of standard organochlorine pesticides mixture (SOPM) increased with the decrease of the extraction temperature at 103 bar. Maximum average percent recovery of SOPM was 98% at $40^{\circ}C/172\;bar$ Average recoveries of SOPM spiked in Pacific cod, flatfish and common squid were 85,74,and 83% respectively at $40^{\circ}C/172\;bar$ Application of supercritical carbon dioxide ectraction offers and attractive alternative to the use of organic solvents for extraction of organochlorine pesticides from fish tissues.

• Applied Biological Chemistry
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• v.42 no.1
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• pp.39-44
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• 1999

Protein profiles of beef loin were constructed by comparing two-dimensional gel electrophoresis patterns of the proteins from different growth stages of Hanwoo, Korean cattle. Proteins from the lean muscle of 0, 6, 12 and 24 months old Hanwoo were separated by isoelectric focusing (IEF) on 16 cm tube gels, and further processed second dimensionally by 12% SDS-polyacrylamide gel electrophoresis (PAGE) using $18{\times}20$ cm gel. Proteins with pI values ranging 3.0 to 9.0 and molecular weight of 15 to 100 kDa could be clearly detected on gel by silver staining. Interestingly, many of the proteins significantly increased and decreased during growth happened to be low molecular ones. To isolate the increased proteins, the soluble proteins were obtained from the tissue by 1% Triton X-100 extraction, then, fractionated by 30% and 50% ammonium sulfate. The isolation condition of each particular protein was determined. According to the conditions, two of the increased proteins were isolated, and transferred to PVDF membrane and microsequenced.

• Journal of the Korean Chemical Society
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• v.36 no.3
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• pp.393-404
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• 1992

The response properties of continuous automated system using an enzyme reactor for determination of urea were investigated. The enzyme reactor was constructed to packed-bed form which filled with nylon-6 beads (42∼48 mesh), which immobilized urease with glutaraldehyde, in teflon tube (2 mm I.D., 20 cm length). The system was composed of the enzyme reactor, gas dialyzer, and tublar PVC-nonactin membrane ammonium ion-selective electrode as an indicator electrode in serial order. The response characteristics of this system were as follows. That is, the concentration range of linear response, slope of linear response, detection limit, and conversion percentage were $5.5{\times}10^{-6}$∼$2.4{\times}10^{-3}M$, 57.8 mV/decade, $1.5{\times}10^{-6}$, and 80.8%, respectively. The optimum buffer and life time of urease reactor were 0.01M Tris-HCl buffer solution (pH 7.0∼7.8) and 0.01M phosphate buffer solution (pH 6.9∼7.5) and about 150 days, respectively. And the urease reactor had no interferences of the other physiological materials.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.1
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• pp.266-274
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• 1996

An experimental work was conducted to investigate the characteristics of the onset of flooding in vertical annuli with a direct injection mode using air and water. The onset of flooding was determined by means of pressure drop measurement while the air velocity was increased gradually under fixed liquid flow rates. Data of the onset of flooding were collected for various combinations of the tube size and the nozzle number. A theoretical analysis of the onset of flooding was also performed based on an envelope theory. The result shows that the onset of flooding in small-scale annuli can be predicted relatively well by the theory. A modified Wallis parameter was used to investigate the scaling effect of flooding phenomena in the annuli, indicating a relatively reasonable result. The number of nozzle has no effect on the flooding velocity when liquid was injected through 2, 3, 4 and 6 nozzles but the initiation of flooding was significantly expedited when 12 nozzles were employed for liquid injection.

• Journal of Plant Biology
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• v.36 no.2
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• pp.127-132
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• 1993

Self-incompatibility in Brassica campestris is controlled by multi-allele system in a single genetic locus, the S locus, and it is elucidated that S-glycoproteins are S gene products. In this experiments, we examined the genetic mode(pollen tube behavior and segregation of S-glycoprotein), characteristic of S-glycoproteins and DNA constitution within nuclear genome on S gene family that unexplained by single locus model, and investigated the segregation pattern of S-glycoproteins in bred F1 generation. By diallel cross among the 15 plants within one family the existence of three types of homozygotes and three types of heterozygotes were observed, and segregation of S-allele could not explained by single locus model. From the results of IEF-immunoblot analysis for non-segregated individual plant, the segregation pattern of S specific bands was corresponded with results of diallel cross except with one case(SaSa genotype). The molecular weight of 6 different S-genotype varied in near by 50 kD, and each genotype expressed with 2 or 3 bands. Specific bands in SaSa, SbSb, ScSc has almost similar molecular weight between them. Southern analysis of genomic DNA probed with S-glycoprotein cDNA for 6 different genotypes revealed that there are clear difference in polymorphism, multiple bands of hybridization, when restriction enzymes of EcoR I were used. It could be assumed that there are several sequences related to the S-glycoprotein structural genes within their nuclear genome. Therefore, we suggested the possibilities that S-allele system could be controlled by multi-locus, that dominance-recessive interactions could be explained by modifier gene or supressor gene based on the results of abnormal segregation of S-glycoprotein in bred F1. The F2 analyses are progressing in now.

• The Korea Journal of Herbology
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• v.23 no.3
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• pp.93-102
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• 2008

Objectives : Forsythiae Fructus (Forsythia koreana Nakai) has been used anti-inflammatory, diuretics, antidote, and antibacterials in traditional herbal medicine. The present study is focused on the inhibitory effect of Forsythiae Fructus ethanol extract (FF-E) on the production of inflammatory mediators such as NO, iNOS and proinflammatory cytokines ($TNF-{\alpha}$, $IL-1{\beta}$ and IL-6) in LPS-stimulated BV-2 cells, a mouse microglial cell line, and investigated the scavenging activity of FF-E. Methods : BV-2 cells were pre-incubated with FF-E for 30 min and then stimulated with LPS (1 ${\mu}g/m{\ell}$) at indicated times. Cell toxicity of GCF was determined by MTT assay. The levels of NO, PGE2 and cytokines were measured by Griess assay and ELISA. The mRNA and protein expressions of iNOS and cytokines were determined by RT-PCR and Western blotting. Free radical scavenging activity of GCF was determined by DPPH assay in tube test. Results : FF-E significantly inhibited the excessive production of NO, $PGE_2$, $TNF-{\alpha}$, and $IL-1{\beta}$ in LPS-stimulated BV-2 cells. In addition, FF-E attenuated the mRNA and protein expressions of iNOS, and proinflammatory cytokines. FF-E also significantly scavenged the DPPH free radicals in a dose-dependent manner. Conclusions : These results indicate that FF-E exhibits anti-inflammatory property by suppressing the transcription of inflammatory mediator genes, suggesting the anti-inflammatory property of FF-E may make it useful as a therapeutic agent for the treatment of human neurodegenerative diseases.

• Journal of Radiation Protection and Research
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• v.28 no.2
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• pp.127-135
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• 2003

The primary contributors to the total occupational radiation exposure in operating nuclear power plants are operation and maintenance activities doting refueling outages. The Advanced Power Reactor 1400 (APR1400) includes a number of design improvements and plans to utilize advanced maintenance methods and robotics to minimize the annual collective dose. The major radiation exposure reduction features implemented in APR1400 are a permanent refueling pool seal, quick opening transfer tube blind flange, improved hydrogen peroxide injection at shutdown, improved permanent steam generator work platforms, and more effective temporary shielding. The estimated average annual occupational radiation exposure for APR1400 based on the reference plant experience and an engineering judgment is determined to be in the order of 0.4 man-Sv, which is well within the design goal of 1 man-Sv. The basis of this average annual occupational radiation exposure estimation is an eighteen (18) month fuel cycle with maintenance performed to steam generators and reactor coolant pumps during refueling outage. The outage duration is assumed to be 28 days. The outage work is to be performed on a 24 hour per day basis, seven (7) days a week with overlapping twelve (12) hour work shifts. The occupational radiation exposure for APR1400 is also determined by an alternate method which consists of estimating radiation exposures expected for the major activities during the refueling outage. The major outage activities that cause the majority of the total radiation exposure during refueling outage such as fuel handling, reactor coolant pump maintenance, steam generator inspection and maintenance, reactor vessel head area maintenance, decontamination, and ICI & instrumentation maintenance activities are evaluated at a task level. The calculated value using this method is in close agreement with the value of 0.4 man-Sv, that has been determined based on the experience aid engineering judgement. Therefore, with the As Low As Reasonably Achievable (ALARA) advanced design features incorporated in the design, APR1400 design is to meet its design goal with sufficient margin, that is, more than a factor of two (2), if operated on art eighteen (18) month fuel cycle.

• Clinical and Experimental Reproductive Medicine
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• v.22 no.2
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• pp.143-148
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• 1995

To present and assess the efficacy of combination of microsurgical epididymal sperm aspiration(MESA) and intracytoplasmic sperm injection(ICSI) for the treatment of infertility due to unreconstructable obstructive azoospermia or congenital bilateral agenesis of vas deferens (CBAVD), MESA was performed in the 45 husbands ( 16 CBAVD, 29 unreconstructable genital tract obstruction), followed by ICSI of oocytes recovered from the wives hyperstimulated by GnRH agonist in combination with hMG and FSH. Cleaving embryos were transfered to the uterine cavity or follopian tube(ZIFT) 18 or 24 hours after ICSI procedure. In 45 cycles of MESA, 492 oocyte complexes were recovered. ICSI was carried out on 355 metaphase II oocytes and 226 oocytes (63.7%) showed normal two pronucleus fertilization. After 198 embryos were transferred in 43 cycles, an average of 5 per cycle, 20 patients presented a positive HCG and intrauterine pregnancy was confirmed by US. So, the clinical ongoing pregnancy rate per transfer was 46.5%. Until now, 8 patients have given birth to 9 babies, 5 male and 4 female, including 1 twin. The babies were all healthy except 1 twin female baby. There was 1 miscarriage at 7 weeks and chromosomal study of abortus revealed as 45X, monosomy. These results suggested that it was possible to achieve high normal fertilization and pregnancy rate by ICSI using epididymal sperm.

• Korean Journal of Optics and Photonics
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• v.16 no.1
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• pp.56-62
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• 2005

Because of the wide plane and the curved field of CRT rear projection high definition television, its MTF(modulation transfer function) can't be easily measured by the usual forward testing method. Then we propose a backward testing method for the MTF so that the object plane and the image analyzer of forward testing are located at positions opposite each other. We prefer to use the backward testing method because the forward testing method has poor accuracy caused by very small numerical aperture, low spatial resolutions, and long depth of focus. We found that the backward testing method was very easy to align and had high repeatability. We confirmed the confidence of results obtained by the backward testing method in comparison with designed results.