• Toxicological Research
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• 제16권2호
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• pp.163-172
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• 2000

Recently, there is a worldwide concern that a great number of man-made chemicals have a hormone-like action both in humans and in animals. DECD is developing screening programs using validated test systems to determine whether certain substances may have an effect in humans. In the present study. the establishment oj repeated-dose toxicity test method was tried. Flutamide. an anti-androgenic agent. was administered by gavage to Sprague-Dawley rats for 28 days at dose levels of 0. 0.5. 3 and 18 mg/kg body weight (10-15 rats/sex/group) to examine the effects on general findings. especially reproductive and endocrine parameters. Clinical signs. body weights, food consumption, and sexual cycle were checked and measured. For the gross and microscopic examinations. 10 rats/sex/group were sacrificed at the end of dosing period and the remaining animals of control and high dose groups (5 each) were sacrificed after 14 days recovery. Examinations for hematology and clinical chemistry were carried out at necropsy. There were no treatment-related changes in clinical signs. body weights, food consumption. gross necropsy. hematology and clinical chemistry at all doses of both sexes. The period and regularity of sexual cycle were not adversely affected at all doses by the test agent. At 18 mg/kg. both decreased weights of prostate, seminal vesicle and epididymis in males and increased weights of spleen and thymus in females were observed. In addition, decreased number of spermatids and sperms. increased serum testosterone concentration and increased incidence (100%) of interstitial cell hyperplasia were seen in males. At 18 mg/kg of the recovery group. decreased prostate weight. reduced sperm count and increased incidence (20%) of interstitial cell hyperplasia in males and increased thymus weight in females were observed. At 3 mg/kg. reduced sperm count was found. There were no adverse effects on parameters examined at 0.5 mg/kg of both sexes. The results suggested that the potential target organs of flutamide may be accessory sexual glands including testes for males and spleen and thymus for females. Taken together. this test method was found to be a useful screening test system for endocrine disrupting chemicals.

• The Korean Journal of Mycology
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• 제13권4호
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• pp.221-224
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• 1985

The life cycle of 17 species of Trichoderma was elucidated to seize the proper stage for observing the nuclear behavior and chromosome count. The most convenient stage for the purpose in their life cycle was the stage just before producing the asexual spore. Of the 17 species in the genus Trichoderma the haploid chromosome numbers were counted 5,6,7 and 10. Six chromosomes were most frequently observed. It is believed that the basic chromosome number is placed between 4 and 10, and that the number might be 6, referring to the related papers. It appears necessary to reclassify the single genus of Trichoderma into at least two or three genera.

• Food Science of Animal Resources
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• 제25권4호
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• pp.500-506
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• 2005

This study was carried out to obtain knowledges on the survival of Streptococcus mutans in the yoghurt added with green tea powder. The growth inhibition of green tea powder on the food borne pathogens and oral bacteria was measured by total microbial count, Among the tested food borne pathogens, the growth of Staphylococcus aureus and Salmonella enteritidis were not significantly affected by the addition of green tea powder, but green tea powder showed the growth inhibition effect on Escherichia coli O157:H7. The number of surviving Streptococcus mutans cell was decreased by $0.56\~0.99log$ cycle after 24 hem incubation by the addition of $0.5\~2.5\%$ green tea powder in the medium. And also the viable cell count of surviving Streptococcus mutans cells (initial inoculum $3.4\times10^7CFU/mL$) were decreased to $1.4\times10^4\~7.2\times10^4 CFU/mL$ after 48 hours incubation when $0.5\~2.5\%$ green tea powder were added to the drinkable yoghurt, Growth of Streptococcus mutans was strongly inhibited by the addition and incubation of green tea powder for 48 hum in the yoghurt.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제33권6호
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• pp.529-532
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• 2000

To establish a food safety of dried layer, heat treatment effect on the bacterial density of dried layers was investigated. And a modified process developing experiment for dried layer products using closing type drying oven was carried out. tittle bacterial density difference on the dried layer products were found before and after heat treatment at $90^{\circ}C$ for 6 hrs called Hwaip treatment having been used for long term storage. Direct or indirect heat treatment of dried lavers using gas burner and frying pan reduced about 1 to 3 log cycle of viable cell count from $10^8\;CFU/g\;to\;10^5\;CFU/g$. Heat treatment by direct surface contact type cooking machine being used in the market place for cooked dried layer products could reduce the viable cell count on the layer product from $2.2{\times}10^5{\~}5.2{\times}10^7\;CFU/g\;to\;7.0{\times}10^2{\~}5.0{\times}10^5\;CFU/g$, Ultraviolet irradiation (20 W, 30 cm) to one or both side of the dried laver products reduced the viable cell count from $2.2{\times}10^6\;CFU/g\;to\;8.0{\times}10^5\;CFU/g\;and\;2.0{\times}10^5\;CFU/g$, respectively. The viable cell count of the dried layer products produced by modified process using a closing type dryer was about $10^3\;CFU/g$ and lower 3 log cycle than that in the products collected in market place and made by open type dryer.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권2호
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• pp.136-141
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• 2005

The capability of utilizing a TCA cycle intermediates as the sole carbon source by the multi-vitamin auxotrophic yeast Torulopsis glabrata CCTCC M202019 was demonstrated with plate count method. It is indicated that T. glabrata could grew on a medium with one of the TCA cycle intermediates as the sole carbon source, but more colonies were observed when glucose, acetate and one of the TCA cycle intermediates coexisted in the medium. Among the intermediates of the TCA cycle examined in this study, cell growth was improved by supplementing oxaloacetate. Further investigation showed that the presence of acetate was necessary when oxaloacetate was supplemented. By supplementing with 10 g/L of oxaloacetate in pyruvate batch fermentation, dry cell weight increased from 11.8 g/L to 13.6 g/L, and pyruvate productivity was enhanced from $0.96\;gL^{-1}h^{-1}\;to\;1.19 gL^{-1}h^{-1}$ after cultivation of 56 h. The yield of pyruvate to glucose was also improved from 0.63 g/g to 0.66 g/g. These results indicate that under vitamins limitation, the productivity and yield of pyruvate could be enhanced via an increase of cell growth by the supplementation of oxaloacetate.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제28권4호
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• pp.428-434
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• 1995

The purpose of this study is to develop a sanitary aquarium for the safety slices of raw fish by using U.V. light. Water re-circulating system was composed of two tanks. One of the tanks $(90\times45\times45cm\;in\;size),$ was used for rearing fish and the other $(90\times45\times45cm\;in\;size),$ with 37 pieces of corrugated plastic plates was used for the growth of Nitrosomonas and Nitrobacter to remove ammonia from the water. Consequently, bactericidal effects of U.V. light were examined under the controlled condition of water with flow rate 730m1/sec (water flow thickness: 10mm), the width 41cm of water flow route, and the distance 4.75cm from the lamp to its water bottom, and U.V. light 75W (5 lamps). The water of the aquarium tank will be theroetically circulated 1 cycle per 18 min. In these conditions the bactericidal effect was $85\%$ just after passing through U,V. light and 3 log cycle in aquarium tank water. The count of Vibrio parahaemolyticus just after irradiation was decreased by about over than 3 log cycle. Under the irradiation for 72 hours, viable cell counts in both skin and gill of fish reared were decreased into about 2 log cycle, but there was no significant decrease in viscera. When the temperature of the tank was controlled at about $20-23^{\circ}C$ under the same condition, viable cell counts were reduced about 2 log cycle, and fecal coliforms were reduced about 1 log rycle and 3 log cycle in Crassostrea gigas and Mytilus edulis, respectively.

• Journal of Microbiology and Biotechnology
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• 제18권8호
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• pp.1453-1458
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• 2008

For quantitative PCR assay of Salmonella enterica serovar Typhimurium in food samples, a real-time PCR method was developed, based on DNA genome equivalent. Specific primers and probe designed based on the STM4497 gene of S. Typhimurium LT2 showed the specificity to S. Typhimurium. Threshold cycle (Ct) values of real-time PCR were obtained from a quantitative standard curve with genomic DNA of Salmonella Typhimurium. In addition, the recovery of S. Typhimurium inoculated artificially to chicken samples with $4.5{\times}10^5$ to 4.5 CFU/ml was evaluated by using real-time PCR and plate-count methods. Result showed that the number of cells calculated from the real-time PCR method had good correlation with that of the plate-count method. This real-time PCR method could be applicable to the detection and quantification of S. Typhimurium in food samples.

• IEMEK Journal of Embedded Systems and Applications
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• 제13권5호
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• pp.269-277
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• 2018

NAND flash memory has widely been used because of non-volatility, low power consumption and fast access time. However, it suffers from inability to provide update-in-place and the erase cycle is limited. The unit of read/write operation is a page and the unit of erase operation is a block. Moreover erase operation is slower than other operations. We proposed the Adaptive Garbage Collection (called "AGC") policy which focuses on not only reducing garbage collection process time for real-time guarantee but also wear-leveling for a flash memory lifetime. The AGC performs better than Cost-benefit policy and Greedy policy. But the AGC does not consider the operation characteristics. So we proposed the Advanced Adaptive Garbage Collection (called "A-AGC") policy which considers the page write operation count and block erase operation count. The A-AGC reduces the write operations by considering the data update frequency and update data size. Also, it reduces the erase operations by considering the file fragmentation. We implemented the A-AGC policy and measured the performance compared with the AGC policy. Simulation results show that the A-AGC policy performs better than AGC, specially for append operation.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3443-3446
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• 2014

The aim of this study was to determine predictive factors for neutropenia after docetaxel-based systemic chemotherapy in patients with castration-resistant prostate cancer (CRPC). The study included 40 Korean CRPC patients who were treated with several cycles of docetaxel plus prednisolone from May 2005 to May 2012. Patients were evaluated for neutropenia risk factors and for the incidence of neutropenia. In this study, nine out of forty patients (22.5%) developed neutropenia during the first cycle of docetaxel-based systemic chemotherapy. Four experienced grade 2, three grade 3, and one grade 4 neutropenia. Multivariate analysis showed that pretreatment white blood cell (WBC) count (p=0.042), pretreatment neutrophil count (p=0.015), pretreatment serum creatinine level (p=0.027), and pretreatment serum albumin level (p=0.017) were significant predictive factors for neutropenia. In conclusion, pretreatment WBC counts, neutrophil counts, serum creatinine levels, and serum albumin levels proved to be significant independent risk factors for the development of neutropenia induced by docetaxel-based systemic chemotherapy in patients with CRPC.

• The Transactions of The Korean Institute of Electrical Engineers
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• 제58권2호
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• pp.342-348
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• 2009

This paper introduces a novel denoising algorithm for the partial-discharge(PD) signals from power apparatuses. The developed algorithm includes three kinds of specific denoising sub-algorithms. The first sub-algorithm uses the fuzzy logic which classifies the noise types in the magnitude versus phase PD pattern. This sub-algorithm is especially effective in the rejection of the noise with high and constant magnitude. The second one is the method simply removing the pulses in the phase sections below the threshold count in the count versus phase pattern. This method is effective in removing the occasional high level noise pulses. The last denoising sub-algorithm uses the grouping characteristics of PD pulses in the 3D plot of the magnitude versus phase versus cycle. This special technique can remove the periodical noise pulses with varying magnitudes, which are very difficult to be removed by other denoising methods. Each of the sub-algorithm has different characteristic and shows different quality of the noise rejection. On that account, a parameter which numerically expresses the noise possessing degree of signal, is defined and evaluated. Using the parameter and above three sub-algorithms, an adaptive complex noise rejection algorithm for the on-line PD diagnosis system is developed. Proposed algorithm shows good performances in the various real PD signals measured from the power apparatuses in the Korean plants.