• Korean Journal of Environmental Agriculture
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• v.29 no.4
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• pp.374-380
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• 2010

This experiment was carried out to investigate the effect of light qualities and lighting types provided by LED Chamber System which designed by Rural Development Administration on growth and development of Chrysanthemum (Dendranthema grandiflorum L., cv. 'Cheonsu') plantlet cultured in vitro. The explants of single-node cuttings were exposed to monochromic or mixture radiation of blue, red, or green under continuous and intermittent lighting for 42 days. The intermittent lighting of 20 sec. on and off per minute significantly stimulated shoot elongation with lower number of internodes compared with continuous lighting treatments. However, continuous blue, red, or green light gave greater dry weight comparing the intermittent lighting, and the lowest weight was recorded at the continuous fluorescent lamp. Otherwise, the plantlet growth in dry weight or leaf area was inhibited by the green light controlled at 50 times intermittence but internode elongation was significantly increased. These results showed that the plantlets were successfully grown under the LED Chamber System controlled with different light qualities and lighting types. Quantitative growth of the plantlets was improved under the shorter photoperiod with a intermittent lighting cycle compared with continuous lighting using fluorescent lamps. It is concluded that the growth and development of in vitro plantlets such as single-node cuttings can be achieved by the controlling of light quality or lighting type during the photoperiod per day with a lower electric cost compared with conventional continuous lighting system.

• The Korean Journal of Food And Nutrition
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• v.17 no.1
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• pp.8-17
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• 2004

The effect of chlorella extract on the growth and acid production of yoghurt starter was investigated in order to prepare the yoghurt added with chlorella extract. The various levels of chlorella extract powder were added to skim milk medium and the medium was fermented by single or mixed culture of 4 types of lactic acid bacteria such as Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus bulgaricus. The changes in acid production(pH, titratable acidity) and number of viable cells of the medium during fermentation in skim milk added with chlorella extract powder have determined. When chlorella extract powder was added to skim milk medium at the levels of 0.5%, 1.0%, 2.0%, and 3.0%, the addition of 0.5% chlorella extract powder with the single culture of Str. thermophilus, Lac. casei, and Lac. bulgaricus showed the highest number of viable cell counts after 9 hours incubation. And also all single cultures of the yoghurt starter produced the higher amounts of acid with the addition of 0.5% chlorella extract powder. When chlorella extract powder was added to the medium at the levels of 0.25%, 0.5%, 1.0%, and 2.0%, the addition of lower lever(0.25∼0.5%) of chlorella extract powder with the mixed culture of the lactic acid bacteria showed more the acidity of pH and the number of viable cell counts. Among the treatments tested, the addition of 0.25% chlorella extract powder with the mixed culture of Str. thermophilus and Lac. casei produced the highest number of viable cell counts after 12 hours incubation. Therefore it was suggested to manufacture the yoghurt with the addition of 0.25% chlorella extract powder and the inoculation of mixed culture of Str. thermophilus and Lac. casei for on the stimulation of growth of the yoghurt starter.

• Journal of Life Science
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• v.32 no.2
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• pp.161-166
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• 2022

Mitosis is a process in which a replicated genome is distributed to two daughter cells, and it is necessary for cell survival and organismal development. During mitosis, the spindle assembly checkpoint (SAC) ensures faithful chromosome segregation by monitoring the kinetochore attachment to the mitotic spindle. Although the SAC mechanism has been extensively studied over the last 30 years, the mechanism by which a single unattached kinetochore activates the SAC remains unclear. The key components of the SAC are Mad1, Mad2, Mad3 (BubR1 in higher eukaryotes), Bub1, Bub3, and Cdc20, which are all required for SAC activation. An essential step for SAC activation is the formation of the Mad2 - Cdc20 complex in the unattached kinetochore, which is kinetically disfavored. Although the mechanism by which Mad2 and Cdc20 are recruited to unattached kinetochores is well-known, it is not clear how they form a complex. Recently, a key mechanism for the formation of the Mad2 - Cdc20 complex has been identified, which is catalyzed by an unattached kinetochore. This supports the evidence that a single unattached kinetochore can activate the SAC signaling. Herein, we discuss the known key mechanism for SAC activation, review the recent studies on SAC, and conclude how their discoveries improved the understanding of mitosis.

• Radiation Oncology Journal
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• v.17 no.4
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• pp.314-320
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• 1999

Purpose : Paclitaxel is a chemotherapeutic agent with potent microtubule stabilizing activity that arrests cells in $G_2$-M phase. Because $G_2$ and M are the most radiosensitive phase of the cell cycle, paclitaxel has potential role as a cell-cycle specific radiosensitizer. This study was peformed to see the effects of paclitaxel on the radiation-induced damage of gastric mucosa of the rat. Materials and Methods : The rats were divided into the three groups i.e., paclitaxel alone group, radiation alone group and, a combination of paclitaxel and radiation in combined group. A single intraperitoneal infusion of paclitaxel (10 mg/kg) was done in paclitaxel alone group. In radiation alone group, a single fraction of irradiation (8 Gy, x-ray) to the whole abdomen and, a combination of a single fraction of irradiation (8 Gy, x-ray) to the whole abdomen was given 24 hrs after paclitaxel infusion In combined group of paclitaxel and radiation. The incidence of mitosis and apoptosis as well as histologic changes of the gastric mucosa were evaluated at 6 hrs, 24 hrs, 3 days and 5 days after treatment. Results : The number of the mitosis was not increased by paclitaxel infusion. The incidence of the apoptosis was similar from 6 hrs to 3 days after paclitaxel infusion and was decreased at 5 days. Paclitaxel induced minimal glandular dilatation and cellular atypia of gastric mucosa at 24 hrs and 3 days. In irradiation group, the incidence of apoptosis was $6.0\%$ in 6 hrs and $1.25\%$ in 24 hrs after irradiation and minimal glandular dilatation and cellular atypia were noted throughout the experimental period. The incidence of apoptosis in the combined group of paclitaxel and irradiation ($4.5\%$) was significantly higher than irradiation alone group ($1.25\%$) at 3 days (p<0.05). Conclusion : Paclitaxel had no mitotic on mitotic arrest in gastric mucosa of the rat. Increased number of apoptosis in combined paclitaxel and irradiation group suggested the additive effects of paclitaxel on irradiation.

• Journal of Radiation Protection and Research
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• v.10 no.2
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• pp.96-108
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• 1985

A study for the assessment of natural environmental radiation exposure at a flat and open field of about $10,000m^2$ in area in CNU Daeduk campus has been carried out by means of gamma-ray scintillation spectrometry and thermoluminescence dosimetry for one year period of time from October 1984. The detectors used were 3'${\phi}{\times}$3' NaI(T1) and two different types of LiF TLD, namely, chip sealed in plastic sheet which tightly pressed on two open holes of a metal plate and Teflon disk. Three 24-hour cycles of in-situ spectrometry, and two 3-month and one 1-month cycles of field TL dosimetry were performed. All the spectra measured were converted into exposure rate by means of G(E) opertaion, and therefrom exposure rate due to terrestrial component of environmental radiation was figured out. Exposure rate determined by the spectrometry was, on average, $(10.54{\pm}2.96){\mu}R/hr$, and the rates of $(12.0{\pm}3.4){\mu}R/hr$ and $(11.0{\pm}3.6){\mu}R/hr$ were obtained from chip and disk TLD, respectively. Fluctuations in diurnal variation of the exposure rate measured by the spectrometry were noticeable sometime even in a single cycle of 24 hours. It is concluded that appropriately combined use of TLD with iu-sitn gamma-ray spectrometry system can give more accurate and precise measure of environmental radiation exposure, and further study for more adequate and sensitive TLD for environmental dosimetry, including improvement and elevation of accuracy in data assessment through inter-laboratory or international intercomparison is necessary.

• Korean Chemical Engineering Research
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• v.57 no.6
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• pp.868-873
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• 2019

In this study, the evaluation of performance of AORFB using methyl viologen and TEMPOL as organic active materials in neutral supporting electrolyte (NaCl) with various membrane types was performed. Using methyl viologen and TEMPOL as active materials in neutral electrolyte solution, the cell voltage is 1.37V which is relatively high value for AORFB. Two types of membranes were examined for performance comparison. First, when using Nafion 117 membrane which is commercial cation exchange membrane, only the charge process occurred in the first cycle and the single cell couldn't work because of its high resistance. However, when using Fumasep anion exchange membrane (FAA-3-50) instead of Nafion 117 membrane, the result was obtained as the totally different charge-discharge graphs. When current density was $40mA{\cdot}cm^{-2}$ and cut off voltage range was from 0.55 V to 1.7 V, the charge efficiency (CE) was 97% and voltage efficiency (VE) was 78%. In addition, the discharge capacity was $1.44Ah{\cdot}L^{-1}$ which was 54% of theoretical capacity ($2.68Ah{\cdot}L^{-1}$) at $10^{th}$ cycle and the capacity loss rate was $0.0015Ah{\cdot}L^{-1}$ per cycle during 50 cycles. Through cyclic voltammetry test, it seems that this difference in the performance between the full cell using Nafion 117 membrane and Fumasep anion exchange membrane came from increasing resistance due to chemical reaction between membrane and active material, not the capacity loss due to cross-over of active material through membrane.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.21 no.1
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• pp.15-21
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• 2021

Purpose: Urea cycle disorder (UCD) is an inherited inborn error of metabolism, acting on each step of urea cycle that cause various phenotypes. The purpose of the study was to investigate the long-term clinical consequences in different groups of UCD to characterize it. Methods: Twenty-two patients with UCD genetically confirmed were enrolled at Pusan National University Children's hospital and reviewed clinical features, biochemical and genetic features retrospectively. Results: UCD diagnosed in the present study included ornithine transcarbamylase deficiency (OTCD) (n=10, 45.5%), argininosuccinate synthase 1 deficiency (ASSD) (n=6, 27.3%), carbamoyl-phosphate synthetase 1 deficiency (CPS1D) (n=3, 13.6%), hyperornithinemia-hyperammonemia-homocitrullinuria syndrome (HHHS) (n=2, 9.1%), and arginase-1 deficiency (ARG1D) (n=1, 4.5%). The age at the diagnosis was 32.7±66.2 months old (range 0.1 to 228.0 months). Eight (36.4%) patients with UCD displayed short stature. Neurologic sequelae were observed in eleven (50%) patients with UCD. Molecular analysis identified 37 different mutation types (14 missense, 6 nonsense, 6 deletion, 6 splicing, 3 delins, 1 insertion, and 1 duplication) including 14 novel variants. Progressive growth impairment and poor neurological outcomes were associated with plasma isoleucine and leucine concentrations, respectively. Conclusion: Although combinations of treatments such as nutritional restriction of proteins and use of alternative pathways for discarding excessive nitrogen are extensively employed, the prognosis of UCD remains unsatisfactory. Prospective clinical trials are necessary to evaluate whether supplementation with BCAAs might improve growth or neurological outcomes and decrease metabolic crisis episodes in patients with UCD.

• Journal of Acupuncture Research
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• v.25 no.3
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• pp.139-162
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• 2008

Objectives : Korean tradithional acupuncture Theory, Sa-am's 5 phases acupuncture method was originated in 1644-1742, in the middle of the Cho Sun dynasty. This study was to vertify the effect of Sa-am Acupuncture Treatment on Primary dysmenorrhea of Women. Methods : The subjects were 80 volunteers who was suffering for dysmenorrhea, employed using Measure of Menstrual Pain (MMP) questionnaire. Subjects were divided into two groups including Sa-am acupuncture treatment group(n=25), minimal acupuncture treatment group(n=22). They had agreed to take part in this experiment, with didn't take any anodyne drugs. In the acupuncture group, subjects were stimulated at G41, $SI_3$, B66, $SI_2$(Small intestine jung-guk), $SP_6$, $CV_6$ and one points were inserted additionally depending the symptoms among $ST_{36}$ or $LI_2$. In the control group, subjects were needled at 5 non-acupuncture points have any effect on Dysmenorrhea. A total of 8 acupuncture sessions were performed for each patient depending on the individual menstruation cycle The MMP score by using 7 questions and the Menstrual Symptom Severity List(MSSL-D) was measured before and after menstruation cycle. Collected data were analyzed as frequency, percentage, paired t-test, independent t-test using SPSS 10.0 WIN Program. Results : Acupuncture treatment produced a significant decreasing the symptom of Primary dysmenorrhea in two groups, but a statistically significant difference was not shown in the acupuncture group compare to control group. Conclusions : Based on the above results, it was verified that Acupuncture Treatment was effective in decreasing the symptom of Primary Dysmenorrhea.

• Journal of the Korea Society for Simulation
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• v.29 no.1
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• pp.57-69
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• 2020

Many researchers have recommended that DBR scheduling would be an efficient method to maintain the balance of their workload among many processes in the general flow shop. However, as product variety has increased in recent years, the process has become more complex and requires the re-entrance of raw materials and work in process. The re-entrant line has known for the complex manufacturing process that raw materials are repeatedly processed on the same machine. This study reviews the applicability of DBR against the re-entrant manufacturing line due to the distinguishing characteristics and the higher complexity caused by multiple visits of a job into the identical process. In order to apply the DBR method to the re-entrant process, the main idea is to reconstruct re-entrant process into a virtual flow process(loop) that has a single bottleneck. This study discusses the following two questions. First, DBR is also superior to traditional scheduling methods against re-entrant manufacturing line. And how we structure and detect the system bottleneck (or sub-bottleneck) through drum-buffer-rope concepts. To answer the above questions, we experimented and analyzed the effects of the applicability of DBR under the general re-entrant process model(TRC, Technology Research Center). As a result, we have identified a balance between loops for cycle time and work in process.

• Journal of Acupuncture Research
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• v.24 no.3
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• pp.63-79
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• 2007

Objectives : Korean traditional acupuncture Theory, Sa-am's 5 phases acupuncture method was originated in 1644-1742, in the middle of the Cho Sun dynasty. This study was to verify the effect of Sa-am Acupuncture Treatment on dysmenorrhea of Women. Methods : The subjects were 49 volunteers who were suffering for dysmenorrhea, employed using Measure of Menstrual Pain (MMP) questionnaire. Subjects were divided into two groups including Sa-am acupuncture treatment group(n=23) and minimal acupuncture treatment group(n=26). They had agreed to take part in tIris experiment, with didn't take any anodyne drugs. In the acupuncture group, subjects were stimulated at $GB_{41}$, $SI_3$, $GL_{66}$, $SI_2$(Small intestine jung-guk) and $SP_6$. In the control group, subjects were needled at $L_{10}$, $S_{40}$, $P_5$, $G_{40}$ points have any effect on dysmenorrhea. A total of 5 acupuncture sessions were performed for each patient depending on the individual menstruation cycle. The MMP score by using 7 questions and the Menstrual Symptom Severity List(MSSL-D) were measured before and after menstruation cycle. Collected data were analyzed as frequency, percentage, paired t-test, independent t-test using SPSS 10.0 WIN Program. Results : Acupuncture treatment produced a significant improvement on dysmenorrhea in two groups, but a statistically significant difference was not shown in the acupuncture group compare to control group. Conclusions : Based on the above results, it was verified that Acupuncture Treatment was effective in decreasing the symptom of Dysmenorrhea.